Aldehyde Dehydrogenase 2 Preserves Mitochondrial Function in the Ischemic Heart: A Redox-dependent Mechanism for AMPK Activation by Thioredoxin-1

ABSTRACT

Aldehyde dehydrogenase 2 (ALDH2) protects the ischemic heart by activating adenosine 5'-monophosphate-activated protein kinase (AMPK) signaling. However, the molecular mechanisms linking ALDH2 and AMPK signaling are not fully understood. This study aimed to explore the potential mechanisms linking ALDH2 and AMPK in myocardial ischemic injury. An ischemic model was established by ligating the left anterior descending coronary artery in rats. The overexpression or knockdown of ALDH2 in H9c2 cells treated with oxygen-glucose deprivation was obtained through lentivirus infection. Transferase-mediated dUTP nick-end labeling was used to evaluate apoptosis in an ischemic rat model and oxygen-glucose deprivation cells. ALDH2 activity, mitochondrial oxidative stress markers, adenosine triphosphate, respiratory control ratio, and cell viability in H9c2 cells were evaluated using a biological kit and 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide. Protein expression of ALDH2 , 4-hydroxynonenal, thioredoxin-1 (Trx-1), and AMPK-proliferator-activated receptor gamma coactivator-1 alpha (PGC-1α) signaling pathway was detected through Western blotting. ALDH2 activation reduced ischemic-induced myocardial infarct size and apoptosis. ALDH2 protected mitochondrial function by enhancing mitochondrial respiratory control ratio and adenosine triphosphate production, alleviated mitochondrial oxidative stress, and suppressed myocardial apoptosis. Moreover, ALDH2 attenuated ischemia-induced oxidative stress and maintained Trx-1 levels by reducing 4-hydroxynonenal, thereby promoting AMPK-PGC-1α signaling activation. Inhibiting Trx-1 or AMPK abolished the cardioprotective effect of ALDH2 on ischemia. ALDH2 alleviates myocardial injury through increased mitochondrial biogenesis and reduced oxidative stress, and these effects were achieved through Trx1-mediating AMPK-PGC1-α signaling activation.

Mechanosensitive ion channel Piezo1 mediates mechanical ventilation-exacerbated ARDS-associated pulmonary fibrosis

INTRODUCTION

Pulmonary fibrosis is a major cause of the poor prognosis of acute respiratory distress syndrome (ARDS). While mechanical ventilation (MV) is an indispensable life-saving intervention for ARDS, it may cause the remodeling process in lung epithelial cells to become disorganized and exacerbate ARDS-associated pulmonary fibrosis. Piezo1 is a mechanosensitive ion channel that is known to play a role in regulating diverse physiological processes, but whether Piezo1 is necessary for MV-exacerbated ARDS-associated pulmonary fibrosis remains unknown.

OBJECTIVES

This study aimed to explore the role of Piezo1 in MV-exacerbated ARDS-associated pulmonary fibrosis.

METHODS

Human lung epithelial cells were stimulated with hydrochloric acid (HCl) followed by mechanical stretch for 48 h. A two-hitmodel of MV afteracidaspiration-inducedlunginjuryin mice was used. Mice were sacrificed after 14 days of MV. Pharmacological inhibition and knockout of Piezo1 were used to delineate the role of Piezo1 in MV-exacerbated ARDS-associated pulmonary fibrosis. In some experiments, ATP or the ATP-hydrolyzing enzyme apyrase was administered.

RESULTS

The stimulation of human lung epithelial cells to HCl resulted in phenotypes of epithelial-mesenchymal transition (EMT), which were enhanced by mechanical stretching. MV exacerbated pulmonary fibrosis in mice exposed to HCl. Pharmacologicalinhibitionorknockout of Piezo1 attenuated the MV-exacerbated EMT process and lung fibrosis in vivo and in vitro. Mechanistically, the observed effects were mediated by Piezo1-dependent Ca2+ influx and ATP release in lung epithelial cells.

CONCLUSIONS

Our findings identify a key role for Piezo1 in MV-exacerbated ARDS-associated pulmonary fibrosis that is mediated by increased ATP release in lung epithelial cells. Inhibiting Piezo1 may constitute a novelstrategyfor the treatment of MV-exacerbated ARDS-associated pulmonary fibrosis.

Diterpenoids from Euphorbia fischeriana with Kv1.3 Inhibitory Activity

Euphorbia diterpenoids possess inhibitory effects of Kv1.3 ion channel, but most of this research has focused on diterpenoids with jatrophane-related or ingenane-related skeletons. In the present study, nine undescribed (1-9) and 16 known (10-25) diterpenoids, based on jatrophane, lathyrane, ingenane, abietane, and atisane skeletons, were identified from the methanol extract of the aerial parts of Euphorbia fischeriana. The structures were established by analysis of the spectroscopic data as well as by single-crystal X-ray diffraction analysis. Among the isolated diterpenoids, macrocyclic jatrophanes and lathyranes exerted Kv1.3 blocking activity. Compound 8 exhibited good selectivity on the inhibition of the Kv 1.3 channel rather than hERG channel, with a selectivity index over 7.0. The selective activity of lathyrane diterpenoids indicates that macrocyclic diterpenoids have the potential to be further investigated as therapeutic agents for the treatment of autoimmune diseases.

Anisodamine hydrobromide in the treatment of critically ill patients with septic shock: a multicenter randomized controlled trial

BACKGROUND

Septic shock is the development of sepsis to refractory circulatory collapse and metabolic derangements, characterized by persistent hypotension and increased lactate levels. Anisodamine hydrobromide (Ani HBr) is a Chinese medicine used to improve blood flow in circulatory disorders. The purpose of this study was to determine the therapeutic efficacy of Ani HBr in the treatment of patients with septic shock.

METHODS

This was a prospective, multicenter, randomized controlled trial focusing on patients with septic shock in 16 hospitals in China. Patients were randomly assigned in a 1:1 ratio to either the treatment group or the control group. The primary endpoint was 28-day mortality. The secondary outcomes included 7-day mortality, hospital mortality, hospital length of stay, vasopressor-free days within 7 days, etc. These indicators were measured and collected at 0, 6h, 24h, 48h, 72h and 7d after the diagnosis.

RESULTS

Between September 2017 and March 2021, 404 subjects were enrolled. 203 subjects received Ani HBr and 201 subjects were assigned to the control group. The treated group showed lower 28-day mortality than the control group. Stratified analysis further showed significant differences in 28-day mortality between the two groups for patients with a high level of illness severity. We also observed significant differences in 7-day mortality, hospital mortality and some other clinical indicators between the two groups.

CONCLUSION

Ani HBr might be an important adjuvant to conventional treatment to reduce 28-day mortality in patients with septic shock. A large-scale prospective randomized multicenter trial is warranted to confirm our results.

Cardiac-targeted PIASy gene silencing mediates deSUMOylation of caveolin-3 and prevents ischemia/reperfusion-induced Nav1.5 downregulation and ventricular arrhythmias

BACKGROUND

Abnormal myocardial Na_v1.5 expression and function cause lethal ventricular arrhythmias during myocardial ischemia-reperfusion (I/R). Protein inhibitor of activated STAT Y (PIASy)-mediated caveolin-3 (Cav-3) SUMO modification affects Cav-3 binding to the voltage-gated sodium channel 1.5 (Na_v1.5). PIASy activity is increased after myocardial I/R, but it is unclear whether this is attributable to plasma membrane Na_v1.5 downregulation and ventricular arrhythmias.

METHODS

Using recombinant adeno-associated virus subtype 9 (AAV9), rat cardiac PIASy was silenced using intraventricular injection of PIASy short hairpin RNA (shRNA). After two weeks, rat hearts were subjected to I/R and electrocardiography was performed to assess malignant arrhythmias. Tissues from peri-infarct areas of the left ventricle were collected for molecular biological measurements.

RESULTS

PIASy was upregulated by I/R (P < 0.01), with increased SUMO2/3 modification of Cav-3 and reduced membrane Na_v1.5 density (P < 0.01). AAV9-PIASy shRNA intraventricular injection into the rat heart downregulated PIASy after I/R, at both mRNA and protein levels (P < 0.05 vs. Scramble-shRNA + I/R group), decreased SUMO-modified Cav-3 levels, enhanced Cav-3 binding to Na_v1.5, and prevented I/R-induced decrease of Na_v1.5 and Cav-3 co-localization in the intercalated disc and lateral membrane. PIASy silencing in rat hearts reduced I/R-induced fatal arrhythmias, which was reflected by a modest decrease in the duration of ventricular fibrillation (VF; P < 0.05 vs. Scramble-shRNA + I/R group) and a significantly reduced arrhythmia score (P < 0.01 vs. Scramble-shRNA + I/R group). The anti-arrhythmic effects of PIASy silencing were also evidenced by decreased episodes of ventricular tachycardia (VT), sustained VT and VF, especially at the time 5-10 min after ischemia (P < 0.05 vs. Scramble-shRNA + IR group). Using in vitro human embryonic kidney 293 T (HEK293T) cells and isolated adult rat cardiomyocyte models exposed to hypoxia/reoxygenation (H/R), we confirmed that increased PIASy promoted Cav-3 modification by SUMO2/3 and Na_v1.5/Cav-3 dissociation after H/R. Mutation of SUMO consensus lysine sites in Cav-3 (K38R or K144R) altered the membrane expression levels of Na_v1.5 and Cav-3 before and after H/R in HEK293T cells.

CONCLUSIONS

I/R-induced cardiac PIASy activation increased Cav-3 SUMOylation by SUMO2/3 and dysregulated Na_v1.5-related ventricular arrhythmias. Cardiac-targeted PIASy silencing mediated Cav-3 deSUMOylation and partially prevented I/R-induced Na_v1.5 downregulation in the plasma membrane of cardiomyocytes, and subsequent ventricular arrhythmias in rats. PIASy was identified as a potential therapeutic target for life-threatening arrhythmias in patients with ischemic heart diseases.

[Retrospective study on the efficacy and safety of low dose apatinib in reversing chemotherapy resistance in sarcoma]

Objective: To explore whether apatinib can reverse the chemotherapy resistance of patients with advanced sarcoma. Methods: The clinical data of advanced sarcoma patients after chemotherapy who received the original chemotherapy regimen combined with low-dose apatinib in Cancer Center of Union Hospital affiliated to Tongji Medical College of Huazhong University of Science and Technology from May 2018 to November 2021 were collected retrospectively to evaluate the efficacy and safety of this regimen. The primary end point was progression-free survival (PFS), and the secondary end points were objective response rate (ORR), disease control rate (DCR), overall survival (OS) and adverse events (AE). The patients were grouped according to the diagnosis: osteosarcoma, soft tissue sarcoma and undifferentiated small round cell sarcoma. And the benefits of combination treatment was investigated with the stratified analysis of best outcome of combined therapy, lines of chemotherapy received, best response and PFS of original chemotherapy. Results: A total of 30 patients were included in this study, including 20 males and 10 females. The mean age was (25.6±14.7) years. There were 9 cases of osteosarcoma, 11 cases of soft tissue sarcoma and 10 cases of undifferentiated small round cell sarcoma. No patient achieved complete response, 8 patients (26.7%) achieved partial response, 19 patients (63.3%) achieved disease stability, the ORR was 26.7%(8/30), and the DCR was 90.0%(27/30). The median PFS and OS were 4.1 and 13.1 months respectively. Among the three different subtypes of sarcoma, the ORR of osteosarcoma was 44.4% (4/9), the median PFS was 4.1 months, and the median OS was not yet achieved; the ORR of undifferentiated small round cell sarcoma was 40% (4/10), the median PFS was 6.4 months, and the median OS was 10.9 months; No response was observed in soft tissue sarcoma, and the median PFS and median OS was 3.5 and 7.3 months respectively. Patients who achieved objective response had better PFS than patients with stable disease (12.8 vs 3.8 months, P=0.015), and patients with PFS≥ 6 months of original chemotherapy had better PFS benefits (12.7 vs 2.7 months, P<0.001). However, the number of original chemotherapy lines and the best response of original chemotherapy had no significant effect on the PFS of this combination regimen. In terms of safety, the related toxicity of apatinib was no more than grade 2, and the grade 4 chemotherapy-related adverse reactions was mainly hematological toxicity, of which 2 patients interrupted treatment because of febrile neutropenia. Conclusion: Low dose apatinib is effective in reversing chemotherapy resistance of osteosarcoma and undifferentiated small round cell sarcoma with acceptable adverse reactions.

[Identification of Chinese herbs in the Qing Royals--Fu Shen and Fu Shen Mu]

The use of Fu Shen and Fu Shen Mu as medicines has had a long history. Today Fu Shen is still taken as bulk medicinal materials, whereas Fu Shen Mu had disappeared in the medical market. Fu Shen, Yun Fu Shen, Bai Fu Shen, and Bao Mu Fu Shen were used in clinical application in the Qing Royals. Bai Fu Shen and Fu Shen Mu are still kept as speciment in the Palace Museum today. It was found that Bai Fu Shen in the Qing Royals was the same as Fu Shen after peeling and pine roots recorded in the herbal literatures of the Ming and Qing dynasties, with their character tests and historical analysis. It can be inferred that Fu Shen, Yun Fu Shen and Bai Fu Shen recorded in the Qing Royals were actually Fu Shen, with pine roots in sclerotia and after peeling and pine roots removed in processing. Bao Mu Fu Shen and Bao Fu Shen should refer to Fu Shen with pine roots. Fu Shen Mu should mean Fu Shen without white sclerotia and peel during processing. Fu Shen, currently used clinically, is Bao Mu Fu Shen in the Qing Dynasty. Fu Shen distinguishes greatly from Fu Shen Mu in their effects. Such identification and analysis of herbs provides a way of thinking for further hurb studies of the Qing Dynasty.

[Technology specification of bedside hypertonic saline-contrast electrical impedance tomography of lung perfusion and clinical application]

Bedside hypertonic saline-contrast electrical impedance tomography (EIT) method for lung perfusion evaluation has several advantages of bedside, simple, noninvasive and radiation-free. For a long time, EIT perfusion image of hypertonic saline was mostly limited to animal experiments, and related clinical research is in the ascendant. This technical specification for clinical application is reached based on our previous researches, review of literatures in this field. The purpose of this technical specification is to facilitate the unified and standardized use of hypertonic saline-contrast EIT technology for regional lung perfusion, to evaluate the safety and quality control of the technology, and to unify the results.

Trichostatin A modulates the macrophage phenotype by enhancing autophagy to reduce inflammation during polymicrobial sepsis

Sepsis is a syndrome of life-threatening organ dysfunction caused by dysregulated host responses to infection. Macrophage polarization is a key process involved in the pathogenesis of sepsis. Recent evidence has demonstrated that autophagy participates in the regulation of macrophage polarization in different phases of inflammation. Here, we investigated whether trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor, promotes the macrophage M2 phenotype by enhancing autophagy to counteract excessive inflammation in a cecal ligation and puncture (CLP) mouse model. TSA stimulation increased the proportions of M2 marker (CD206, CD124 and CD23)-labeled RAW264.7 macrophages. Furthermore, with increasing TSA doses, autophagy was enhanced gradually. Interestingly, the autophagy activator rapamycin (Rap), also known as an mTOR inhibitor, unexpectedly decreased the proportions of M2 marker-labeled macrophages. However, TSA treatment reversed the Rap-induced decreases in CD206-labeled macrophages. Next, we stimulated different groups of RAW264.7 cells with the autophagy inhibitors MHY1485 or 3-methyladenine (3-MA). Inhibition of autophagy at any stage in the process suppressed TSA-induced macrophage M2 polarization, but the effect was not associated with mTOR activity. In vivo, TSA administration promoted peritoneal macrophage M2 polarization, increased LC3 II expression, attenuated sepsis-induced organ (lung, liver and kidney) injury, and altered systemic inflammatory cytokine secretion. However, 3-MA abolished the protective effects of TSA in CLP mice and decreased the number of M2 peritoneal macrophages. Therefore, TSA promotes the macrophage M2 phenotype by enhancing autophagy to reduce systemic inflammation and ultimately improves the survival of mice with polymicrobial sepsis.

Activation of death-associated protein kinase 1 promotes neutrophil apoptosis to accelerate inflammatory resolution in acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is a uniform progression of overwhelming inflammation in lung tissue with extensive infiltration of inflammatory cells. Neutrophil apoptosis is thought to be a significant process in the control of the resolution phase of inflammation. It has been proved that 5-Aza-2'-deoxycytidine (Aza) can inhibit cancer by activating death-associated protein kinase 1 (DAPK1) to promote apoptosis. However, the effect of DAPK1 on neutrophil apoptosis is unclear, and research on the role of Aza in inflammation is lacking. Here, we investigated whether Aza can regulate DAPK1 expression to influence the fate of neutrophils in ARDS. In vitro, we stimulated neutrophil-like HL-60 (dHL-60) cells with different concentrations of Aza for different durations and used RNA interference to up- or downregulate DAPK1 expression. We observed that culturing dHL-60 cells with Aza increased apoptosis by inhibiting NF-κB activation to modulate the expression of Bcl-2 family proteins, which was closely related to the levels of DAPK1. In vivo, ARDS was evoked by intratracheal instillation of lipopolysaccharide (LPS; 3 mg/kg). One hour after LPS administration, mice were treated with Aza (1 mg/kg, i.p.). To inhibit DAPK1 expression, mice were intraperitoneally injected with a DAPK1 inhibitor. Aza treatment accelerated inflammatory resolution in LPS-induced ARDS by suppressing pulmonary edema, alleviating lung injury and decreasing the infiltration of inflammatory cells in bronchoalveolar lavage fluid (BALF). Moreover, Aza reduced the production of proinflammatory cytokines. However, administration of the DAPK1 inhibitor attenuated the protective effects of Aza. Similarly, the proapoptotic function of Aza was prevented when DAPK1 was inhibited either in vivo or in vitro. In summary, Aza promotes neutrophil apoptosis by activating DAPK1 to accelerate inflammatory resolution in LPS-induced ARDS. This study provides the first evidence that Aza prevents LPS-induced neutrophil survival by modulating DAPK1 expression.

[Clinical characteristics of hepatic flare and efficacy of antiviral therapy in pregnant women with chronic hepatitis B virus infection]

Objective: To analyze the clinical characteristics of hepatic flare and evaluate efficacy of antiviral treatment in pregnant women with chronic HBV infection. Methods: A single-center, open-label, prospective study was conducted, and pregnant women with chronic HBV infection were enrolled. Liver function, HBV serum markers and HBV DNA of pregnant women with chronic HBV infection were reviewed during every 4 to 12 weeks of gestation period. The proportion and clinical characteristics of hepatitis flare during pregnancy were observed. Logistic regression analysis was used to predict hepatic flare in pregnant women with chronic HBV infection. Antiviral therapy with telbivudine (LdT) or tenofovir dipivoxil (TDF) was used to treat hepatic flare during pregnancy. Sequential entecavir (ETV) or TDF was applied after the delivery. Treatment course and drug withdrawal in pregnant women with hepatic flare was the same as those of the general patients with chronic hepatitis B. Liver function, HBV serum markers and HBV DNA were measured in pregnant women with hepatic flare at different time points (4, 12, 24 and 52 weeks). A t-test was used to compare the hepatic flare in pregnant women with and without hepatitis group. HBsAg and HBeAg were used to quantify the receiver operating characteristic (ROC) curve of pregnant women with hepatic flare during pregnancy. Area under the ROC curve was used to calculate the optimal cut-off value corresponding to the maximum sensitivity and specificity of the ROC curve. Results: Of the 220 pregnant women with chronic HBV infection, 55 (25%) had hepatitis flare during pregnancy and received antiviral treatment. Among the 55 women with hepatic flare during gestation, 47 (85.46%) had hepatic flare in the mid-second trimester (12-24 weeks); average peak value of alanine aminotransferase (ALT) was 220.62 U/L, and the average peak value of ALT in 32 cases (58.18%) of pregnant women with hepatic flare was between 2-5 × ULN. HBsAg and HBeAg quantification were significantly lower in pregnant women with hepatic flare during pregnancy than with non-hepatitis (t = -3.745, P < 0.001; t = -2.186, P = 0.030). Multivariate logistic regression analysis showed that pregnant women with HBeAg < 3.065 log10 s/co were 7.576 times more likely to have hepatic flare during pregnancy (95% confidence interval: 3.779-15.190). ALT normalization, undetectable HBV DNA levels, HBeAg loss and HBeAg seroconversion in 55 pregnant women with hepatic flare at 52-week treatment was 100% (55/55), 74.55% (41/55), 47.27% (26/55) and 41.82% (23/55), respectively. HBsAg quantification at 52 weeks was significantly lower than baseline HBsAg quantification (3.32 + 0.37) log(10) IU/ml and (3.95 + 0.40) log(10) IU/ml; t = 8.465, P < 0.001). Conclusion: Hepatic flare often occurs in the second trimester of pregnancy in pregnant women with chronic HBV infection and baseline HBeAg quantification is an independent predictor of hepatic flare. HBeAg seroconversion rate increased at 52 weeks after antiviral therapy.

Hyperforin improves post-stroke social isolation‑induced exaggeration of PSD and PSA via TGF-β

Stroke survivors often experience social isolation, which can lead to post-stroke depression (PSD) and post-stroke anxiety (PSA) that can compromise neurogenesis and impede functional recovery following the stroke. The present study aimed to investigate the effects and mechanisms of post-stroke social isolation-mediated PSD and PSA on hippocampal neurogenesis and cognitive function. The effects of the natural antidepressant hyperforin on post-stroke social isolation-mediated PSD and PSA were also investigated. In the present study, a model of PSD and PSA using C57BL/6J male mice was successfully established using middle cerebral artery occlusion combined with post-stroke isolated housing conditions. It was observed that PSD and PSA were more prominent in the isolated mice compared with the pair-housed mice at 14 days post-ischemia (dpi). Mice isolated 3 dpi exhibited decreased transforming growth factor-β (TGF-β) levels and impairment of hippocampal neurogenesis and memory function at 14 dpi. Intracerebroventricular administration of recombinant TGF-β for 7 consecutive days, starting at 7 dpi, restored the reduced hippocampal neurogenesis and memory function induced by social isolation. Furthermore, intranasal administration of hyperforin for 7 consecutive days starting at 7 dpi improved PSD and PSA and promoted hippocampal neurogenesis and memory function in the isolated mice at 14 dpi. The inhibition of TGF-β with a neutralizing antibody prevented the effects of hyperforin. In conclusion, the results revealed a previously uncharacterized role of hyperforin in improving post-stroke social isolation-induced exaggeration of PSD and PSA and, in turn, promoting hippocampal neurogenesis and cognitive function via TGF-β.

[An analysis of coping styles and subjective well-being among nurses in the emergency treatment room of grade A tertiary hospitals in a province of China]

Objective: To investigate the coping styles and subjective well-being of nurses in the emergency treatment room of grade A tertiary hospitals in a province of China, and to explore the relationship between coping styles and subjective well-being. Methods: In January 2016, 189 nurses in the emergency treatment room were selected from 9 grade A tertiary hospitals in a province of China by random sampling. The general data, coping styles, and subjective well-being of these nurses were analyzed using the general questionnaire, coping style questionnaire, and Campbell index of well-being scale, respectively. Results: The total score of subjective well-being of nurses in the emergency treatment room was 7.54, and the subjective well-being was significantly different between the nurses with different professional titles and between those with different education levels (F=3.46 and 3.47, both P<0.05). The score of illusion coping style differed significantly across the nurses of different ages (F=5.17, P<0.05) , the scores of self-reproach, illusion, and withdrawal coping styles differed significantly across the nurses with different nursing years (F=3.99, 5.30, and 4.97, all P<0.05) , and the score of illusion coping style differed significantly across the nurses with different education levels (F=5.09, P<0.05). Most (71.9%) of the nurses in the emergency treatment room adopted the mature coping style. Subjective well-being was positively correlated with problem-solving, help-seeking, and rationalization (r=0.232, 0.018, and 0.167, all P<0.05) and negatively correlated with withdrawal (r=-0.146, P<0.05) . Conclusion: Most nurses in the emergency treatment room adopt the mature coping style. Their subjective well-being and coping style vary with different ages, nursing years, professional titles, and education levels, and the subjective well-being is relatively low.

Enriched housing promotes post-stroke functional recovery through astrocytic HMGB1-IL-6-mediated angiogenesis

Enriched environment (EE) is shown to promote angiogenesis, neurogenesis and functional recovery after ischemic stroke. However, the underlying mechanisms remain unclear. C57BL/6 mice underwent middle cerebral artery occlusion (60 min) followed by reperfusion, after which mice were housed in either standard environment (SE) or EE. Here we found that post-ischemic EE exhibited decreased depression and anxiety-like behavior, and promoted angiogenesis and functional recovery compared to SE mice. EE mice treated with high-mobility group box-1 (HMGB1) inhibitor glycyrrhizin had an increased post-stroke depression and anxiety-like behavior, and the angiogenesis and functional recovery were decreased. HMGB1 and interleukin-6 (IL-6) expression in astrocyte were increased in EE mice. EE mice treated with glycyrrhizin decreased, whereas EE mice treated with recombinant HMGB1 (rHMGB1) increased the levels of IL-6 and p-AKT. Blockade of IL-6 with anti-IL-6-neutralizing antibody in EE mice attenuated EE-mediated angiogenesis and functional recovery. Furthermore, our in vitro data revealed that in primary astrocyte cultures rHMGB1 promoted the expression of IL-6 in activated astrocytes. PI₃K/AKT signaling pathway was involved in HMGB1-mediated expression of astrocytic IL-6. Thus, our results reveal a previously uncharacterized property of HMGB1/IL-6 signaling pathway in EE-mediated angiogenesis and functional recovery after ischemic stroke.

Hydrogen peroxide preferentially activates capsaicin-sensitive high threshold afferents via TRPA1 channels in the guinea pig bladder

BACKGROUND AND PURPOSE

There is increasing evidence suggesting that ROS play a major pathological role in bladder dysfunction induced by bladder inflammation and/or obstruction. The aim of this study was to determine the effect of H₂ O₂ on different types of bladder afferents and its mechanism of action on sensory neurons in the guinea pig bladder.

EXPERIMENTAL APPROACH

'Close-to-target' single unit extracellular recordings were made from fine branches of pelvic nerves entering the guinea pig bladder, in flat sheet preparations, in vitro.

KEY RESULTS

H₂ O₂ (300-1000 μM) preferentially and potently activated capsaicin-sensitive high threshold afferents but not low threshold stretch-sensitive afferents, which were only activated by significantly higher concentrations of hydrogen peroxide. The TRPV1 channel agonist, capsaicin, excited 86% of high threshold afferents. The TRPA1 channel agonist, allyl isothiocyanate and the TRPM8 channel agonist, icilin activated 72% and 47% of capsaicin-sensitive high threshold afferents respectively. The TRPA1 channel antagonist, HC-030031, but not the TRPV1 channel antagonist, capsazepine or the TRPM8 channel antagonist, N-(2-aminoethyl)-N-[[3-methoxy-4-(phenylmethoxy)phenyl]methyl]thiophene-2-carboxamide, significantly inhibited the H₂ O₂ -induced activation of high threshold afferents. Dimethylthiourea and deferoxamine did not significantly change the effect of H₂ O₂ on high threshold afferents.

CONCLUSIONS AND IMPLICATIONS

The findings show that H₂ O₂ , in the concentration range detected in inflammation or reperfusion after ischaemia, evoked long-lasting activation of the majority of capsaicin-sensitive high threshold afferents, but not low threshold stretch-sensitive afferents. The data suggest that the TRPA1 channels located on these capsaicin-sensitive afferent fibres are probable targets of ROS released during oxidative stress.

AMPK Mediates Glucocorticoids Stress-Induced Downregulation of the Glucocorticoid Receptor in Cultured Rat Prefrontal Cortical Astrocytes

Chronic stress induces altered energy metabolism and plays important roles in the etiology of depression, in which the glucocorticoid negative feedback is disrupted due to imbalanced glucocorticoid receptor (GR) functions. The mechanism underlying the dysregulation of GR by chronic stress remains elusive. In this study, we investigated the role of AMP-activated protein kinase (AMPK), the key enzyme regulating cellular energy metabolism, and related signaling pathways in chronic stress-induced GR dysregulation. In cultured rat cortical astrocytes, glucocorticoid treatment decreased the level, which was accompanied by the decreased expression of liver kinase B1 (LKB1) and reduced phosphorylation of AMPK. Glucocorticoid-induced effects were attenuated by glucocorticoid-inducible kinase 1 (SGK1) inhibitor GSK650394, which also inhibited glucocorticoid induced phosphorylation of Forkhead box O3a (FOXO3a). Furthermore, glucocorticoid-induced down-regulation of GR was mimicked by the inhibition of AMPK and abolished by the AMPK activators or the histone deacetylase 5 (HDAC5) inhibitors. In line with the role of AMPK in GR expression, AMPK activator metformin reversed glucocorticoid-induced reduction of AMPK phosphorylation and GR expression as well as behavioral alteration of rats. Taken together, these results suggest that chronic stress activates SGK1 and suppresses the expression of LKB1 via inhibitory phosphorylation of FOXO3a. Downregulated LKB1 contributes to reduced activation of AMPK, leading to the dephosphorylation of HDAC5 and the suppression of transcription of GR.

MARESIN 1 PREVENTS LIPOPOLYSACCHARIDE-INDUCED NEUTROPHIL SURVIVAL AND ACCELERATES RESOLUTION OF ACUTE LUNG INJURY

Acute lung injury (ALI) is characterized by lung inflammation and diffuse infiltration of neutrophils. Neutrophil apoptosis is recognized as an important control point in the resolution of inflammation. Maresin 1 (MaR1) is a new docosahexaenoic acid-derived proresolving agent that promotes the resolution of inflammation. However, its function in neutrophil apoptosis is unknown. In this study, isolated human neutrophils were incubated with MaR1, the pan-caspase inhibitor z-VAD-fmk, and lipopolysaccharide (LPS) to determine the mechanism of neutrophil apoptosis. Acute lung injury was induced by intratracheal instillation of LPS. In addition, mice were treated with MaR1 intravenously at the peak of inflammation and administered z-VAD-fmk intraperitoneally. We found that culture of isolated human neutrophils with LPS dramatically delayed neutrophil apoptosis through the phosphorylation of AKT, ERK, and p38 to upregulate the expression of the antiapoptotic proteins Mcl-1 and Bcl-2, which was blocked by pretreatment with MaR1 in vitro. In mice, MaR1 accelerated the resolution of inflammation in LPS-induced ALI through attenuation of neutrophil accumulation, pathohistological changes, and pulmonary edema. Maresin 1 promoted resolution of inflammation by accelerating caspase-dependent neutrophil apoptosis. Moreover, MaR1 also reduced the LPS-induced production of proinflammatory cytokines and upregulated the production of the anti-inflammatory cytokine interleukin-10. In contrast, treatment with z-VAD-fmk inhibited the proapoptotic action of MaR1 and attenuated the protective effects of MaR1 in LPS-induced ALI. Taken together, MaR1 promotes the resolution of LPS-induced ALI by overcoming LPS-mediated suppression of neutrophil apoptosis.

Delayed Treatment with Green Tea Polyphenol EGCG Promotes Neurogenesis After Ischemic Stroke in Adult Mice

(-)-Epigallocatechin-3‑gallate (EGCG), the predominant constituent of green tea, has been demonstrated to be neuroprotective against acute ischemic stroke. However, the long-term actions of EGCG on neurogenesis and functional recovery after ischemic stroke have not been identified. In this study, C57BL/6 mice underwent middle cerebral artery occlusion (60 min) followed by reperfusion for 28 days. Neural progenitor cells (NPCs) were isolated from ipsilateral subventricular zone (SVZ) at 14 days post-ischemia (dpi). The effects of EGCG on the proliferation and differentiation of NPCs were examined in vivo and in vitro. Behavioral assessments were made 3 days before MCAO and at 28 dpi. SVZ NPCs were stimulated with lipopolysaccharide (LPS) in vitro to mimic the inflammatory response after ischemic stroke. We found that 14 days treatment with EGCG significantly increased the proliferation of SVZ NPCs and the migration of SVZ neuroblasts, as well as functional recovery, perhaps through M2 phenotype induction in microglia. LPS stimulation promoted the neuronal differentiation in cultured NPCs from the ischemic SVZ. EGCG treatment (20 or 40 μM) further significantly increased the neuronal differentiation of LPS-stimulated SVZ NPCs. After screening for multiple signaling pathways, the AKT signaling pathway was found to be involved in EGCG-mediated proliferation and neuronal differentiation of NPCs in vitro. Taken together, our results reveal a previously uncharacterized role of EGCG in the augment of proliferation and neuronal differentiation of SVZ NPCs and subsequent spontaneous recovery after ischemic stroke. Thus, the beneficial effects of EGCG on neurogenesis and stroke recovery should be considered in developing therapeutic approaches.

Efficacy of different fluids preload on propofol injection pain: A randomized, controlled, double-blinded study

Injection pain of propofol remains a common clinical problem. Previous studies demonstrated that propofol injection pain was alleviated by applying nitroglycerin ointment to the skin of injection site, which inspires us to test whether venous vasodilation induced by fluid preload could alleviate the pain. Different types or volumes of fluid preload were compared. 200 ASA I-II adult patients were randomly assigned to five groups of 40 each. A 20 G cannula was established on the dorsum or wrist of the hand. When fluid preload given with Plasma-Lyte A 100 mL (P100 group), 250 mL (P250 group), 500 mL (P500 group), 0.9% saline 500 mL (N500 group) or Gelofusine 500 mL (G500 group) was completed within 30 min, respectively, Propofol (0.5 mg/kg, 1%) was injected at a rate of 0.5 mL/s. A blind investigator assessed the pain using a four-point scale. Incidence of pain in P100, P250, and P500 groups was 87.5%, 57.5% and 35%, respectively (P<0.05). The median pain intensity score was significantly lower in P500 group than that in P250 and P100 groups (P<0.05 and P<0.01, respectively). Comparison of the effect of different types of solution preload indicated that the highest incidence of pain was in N500 group (62.5%) (N500 vs. P500, P=0.014; N500 vs. G500, P=0.007). The median pain intensity score in N500 group was higher than that in P500 group (P<0.05) and G500 group (P<0.05). There was no significant difference between P500 and G500 groups. It is suggested that Plasma-Lyte A or Gelofusine preload with 500 mL before propofol injection is effective in alleviating propofol-induced pain.

MCT1 and MCT4 expression during myocardial ischemic-reperfusion injury in the isolated rat heart

BACKGROUND/AIMS

Myocardium ischemia-reperfusion (I/R) injury can be caused by imbalances in cellular metabolism. Lactate, transported by monocarboxylate transporters (MCTs), has been implicated as a mechanism in this process. The present study was designed to investigate the expression and functional role of MCTs in rat hearts during ischemia and reperfusion.

METHODS

Langendorff-perfused rat hearts were subjected to 20 minutes stabilization, 30 minutes of global ischemia and 60 minutes reperfusion. Hearts were collected serially for detecting expression changes in MCT1, MCT4 during myocardial I/R injury and lactate concentration was measured. Post-ischemic left ventricular function and infract size were determined at end-point, followed by the pretreatment of D-lactate, a competitive inhibitor of MCTs.

RESULTS

MCT4 was significantly increased following global ischemia and MCT1 expression was increased during the early stages of reperfusion in isolated rat hearts, while the expression of the ancillary protein CD147 was increased during I/R injury. We determined increases in AMPK phosphorylation status, which was significantly elevated following ischemia and early reperfusion. Blocking monocarboxylate transport by competitive inhibition with D-lactate caused decreased left ventricular performance and increased infarct size.

CONCLUSION

Increased MCT4 expression facilitates lactate extrusion during the ischemic period, while increased MCT1 may facilitate lactate transport into and out of cells simultaneously during early reperfusion, with increases in AMPK phosphorylation status during the myocardial I/R period. Lactate transport by MCTs has a profound protective effect during myocardial ischemia reperfusion injury.

BML-111 attenuates hemorrhagic shock-induced acute lung injury through inhibiting activation of mitogen-activated protein kinase pathway in rats

BACKGROUND

Hemorrhagic shock activates cellular stress signals and can lead to systemic inflammatory response, organ injury, and death. Mitogen-activated protein kinase (MAPK) acts as a sensor of tissue injury in models of ischemia-reperfusion injury. Lipoxins are endogenous lipid mediators with potent anti-inflammatory and pro-resolving actions. We hypothesized that BML-111 (a lipoxin A4-receptor agonist) attenuates hemorrhagic shock-induced acute lung injury (ALI) through inhibiting activation of the MAPK pathway.

METHODS

We randomized Sprague-Dawley rats into four groups: sham, hemorrhagic shock-resuscitation (HS), HS plus BML-111 (BML-111), and HS plus BML-111 and BOC-2 (BOC-2). Two hours after resuscitation, we collected samples of lung. We obtained bronchoalveolar lavage fluid for neutrophil count. We performed optical microscopy to examine pathologic changes in lungs. Wet/dry ratios, myeloperoxidase expression, interleukin (IL)-1β and IL-6 levels in lung were measured. We evaluated MAPK activation and the DNA binding activity of activator protein-1 in lung.

RESULTS

Treatment with BML-111 reduced the lung damage and wet/dry ratio, neutrophil count in bronchoalveolar lavage fluid, expression of myeloperoxidase, and production of IL-1β and IL-6 in lung. Phosphorylation of MAPK was also decreased by BML-111 in lung. Furthermore, the DNA binding activity of activator protein-1 was blocked by BML-111. An antagonist of the lipoxin A4-receptor, BOC-2, reversed the protective effect of BML-111 on ALI induced by hemorrhagic shock.

CONCLUSIONS

This study indicates that BML-111 attenuated hemorrhagic shock-induced ALI via the MAPK/activator protein-1 signaling pathway. Therefore, BML-111 may have therapeutic potential for hemorrhagic shock-induced ALI.

Aerobic degradation of tetrabromobisphenol-A by microbes in river sediment

This study investigated the aerobic degradation of tetrabromobisphenol-A (TBBPA) and changes in the microbial community in river sediment from southern Taiwan. Aerobic degradation rate constants (k(1)) and half-lives (t(1/2)) for TBBPA (50 μg g(-1)) ranged from 0.053 to 0.077 d(-1) and 9.0 to 13.1 d, respectively. The degradation of TBBPA (50 μg g(-1)) was enhanced by adding yeast extract (5 mg L(-1)), sodium chloride (10 ppt), cellulose (0.96 mg L(-1)), humic acid (0.5 g L(-1)), brij 30 (55 μM), brij 35 (91 μM), rhamnolipid (130 mg L(-1)), or surfactin (43 mg L(-1)), with rhamnolipid yielding a higher TBBPA degradation than the other additives. For different toxic chemicals in the sediment, the results showed the high-to-low order of degradation rates were bisphenol-A (BPA) (50 μg g(-1))>nonylphenol (NP) (50 μg g(-1))>4,4'-dibrominated diphenyl ether (BDE-15) (50 μg g(-1))>TBBPA (50 μg g(-1))>2,2',3,3',4,4',5,5',6,6'-decabromodiphenyl ether (BDE-209) (50 μg g(-1)). The addition of various treatments changed the microbial community in river sediments. The results also showed that Bacillus pumilus and Rhodococcus ruber were the dominant bacteria in the process of TBBPA degradation in the river sediments.

BML-111, a lipoxin receptor agonist, protects haemorrhagic shock-induced acute lung injury in rats

OBJECTIVES

The main pathogenesis of acute lung injury induced by haemorrhagic shock is inflammation. BML-111, a lipoxinA(4)-receptor agonist, promotes acute inflammatory resolution. We sought to elucidate whether BML-111 protects haemorrhagic shock-induced acute lung injury in rats.

METHODS

Thirty two adult male rats were randomized to sham group (sham), haemorrhagic shock/resuscitation (HS), HS plus BML-111 (BML-111), and HS plus BML-111 and BOC-2 (BOC-2). Haemorrhagic shock was induced by blood drawing, and then resuscitation was obtained by infusion of shed blood and two-fold volume saline.

RESULTS

Histological findings, as well as assays of neutrophilic infiltration (myeloperoxidase activity, ICAM-1 expression), inflammatory cytokines and pro-inflammatory factor (IκB-α and NF-κB p65) confirmed that haemorrhagic shock induced acute lung injury. BML-111 significantly mitigated acute lung injury induced by haemorrhagic shock. However, BOC-2, an antagonist of the lipoxinA(4)-receptor, partially reversed the protective effect of BML-111 on the haemorrhagic shock-induced the acute lung injury.

CONCLUSION

BML-111 protects haemorrhagic shock-induced acute lung injury in rats.

A lipoxin A4 analog ameliorates blood-brain barrier dysfunction and reduces MMP-9 expression in a rat model of focal cerebral ischemia-reperfusion injury

LXA(4) methyl ester (LXA(4)ME), a lipoxin A(4) analog, reduces ischemic insult in the rat models of transient or permanent cerebral ischemic injury. We investigated whether LXA(4)ME could ameliorate blood-brain barrier (BBB) dysfunction after stroke by reducing matrix metalloproteinase (MMP)-9 expression. Adult male rats were subjected to 2-h middle cerebral artery occlusion (MCAO) followed by 24-h reperfusion. Brain infarctions were detected by triphenyltetrazolium chloride (TTC) staining. BBB dysfunction was determined by examining brain edema and Evans Blue extravasation. Temporal expression of MMP-9 was determined by zymography and Western blot. The presence of tissue inhibitors of metalloproteinase-1 (TIMP-1) was also determined by Western blot in tissue protein sample. Brain edema and Evans Blue leakage were significantly reduced after stroke in the LXA(4)ME group and were associated with reduced brain infarct volumes. MMP-9 activity and expression were inhibited by LXA(4)ME after stroke. In addition, LXA(4)ME significantly increased TIMP-1 protein levels. Our results indicate that LXA(4)ME reduces brain injury by improving BBB function in a rat model of MCAO, and that a relationship exists between BBB permeability and MMP-9 expression following ischemic insult. Furthermore, these results suggest that LXA(4)ME-mediated reduction of MMP-9 following stroke are attributed to increased TIMP-1 expression.

Melatonin reduces acute lung injury in endotoxemic rats

BACKGROUND

Treatment with melatonin significantly reduces lung injury induced by bleomycin, paraquat and ischemia reperfusion. In the present study, we investigated the possible protective roles of melatonin in pulmonary inflammation and lung injury during acute endotoxemia.

METHODS

Thirty-two male Sprague-Dawley rats were randomly assigned to four groups: vehicle + saline group, melatonin + saline group, vehicle + lipopolysaccharide group, melatonin + lipopolysaccharide group. The rats were treated with melatonin (10 mg/kg, intraperitoneal injection (i.p.)) or vehicle (1% ethanol saline), 30 minutes prior to lipopolysaccharide administration (6 mg/kg, intravenous injection). Four hours after lipopolysaccharide injection, samples of pulmonary tissue were collected. Blood gas analysis was carried out. Optical microscopy was performed to examine pathological changes in lungs and lung injury score was assessed. Wet/dry ratios (W/D), myeloperoxidase activity, malondialdehyde concentrations and tumor necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10) levels in lungs were measured. The pulmonary expression of nuclear factor-kappa B (NF-kappaB) p65 was evaluated by Western blotting.

RESULTS

PaO(2) in the vehicle + lipopolysaccharide group decreased compared with that in the vehicle + saline group. This decrease was significantly reduced in the melatonin + lipopolysaccharide group. The lung tissues from the saline + lipopolysaccharide group were significantly damaged, which were less pronounced in the melatonin + lipopolysaccharide group. The W/D ratio increased significantly in the vehicle + lipopolysaccharide group (6.1 +/- 0.18) as compared with that in the vehicle + saline group (3.61 +/- 0.3) (P < 0.01), which was significantly reduced in the melatonin + lipopolysaccharide group (4.8 +/- 0.25) (P < 0.01). Myeloperoxidase activity and malondialdehyde levels increased significantly in the vehicle + lipopolysaccharide group compared with that in the vehicle + saline group, which was reduced in the melatonin + lipopolysaccharide group. The TNF-alpha level of pulmonary tissue increased significantly in the vehicle + lipopolysaccharide group ((8.7 +/- 0.91) pg/mg protein) compared with that in the vehicle + saline group ((4.3 +/- 0.62) pg/mg protein, P < 0.01). However, the increase of TNF-alpha level of pulmonary tissue was significantly reduced in the melatonin + lipopolysaccharide group ((5.9 +/- 0.56) pg/mg protein, P < 0.01). Pulmonary IL-10 levels were elevated markedly in the vehicle + lipopolysaccharide group in contrast to that in the vehicle + saline group, whereas the elevation was augmented in the melatonin + lipopolysaccharide group. The nuclear localization of p65 increased markedly in the vehicle + lipopolysaccharide group and this enhancement of nuclear p65 expression was much less in the melatonin + lipopolysaccharide group.

CONCLUSION

Melatonin reduces acute lung injury in endotoxemic rats by attenuating pulmonary inflammation and inhibiting NF-kappaB activation.

Reduction of pulmonary inflammatory response by erythropoietin in a rat model of endotoxaemia

BACKGROUND

Erythropoietin elicits protective effects in lung tissue injury induced by ischaemic reperfusion and hyperoxia. We investigated the protective roles of erythropoietin in pulmonary inflammation and lung injury during acute endotoxaemia.

METHODS

A total of 32 male Sprague-Dawley rats were randomly assigned to four groups: saline group, erythropoietin + saline group, saline + lipopolysaccharide group and erythropoietin + lipopolysaccharide group. Rats were treated with erythropoietin (3000 U/kg, i.p.) or saline, 30 minutes prior to lipopolysaccharide administration (6 mg/kg, i.v.). Four hours after lipopolysaccharide injection, samples of pulmonary tissue were collected. Optical microscopy was performed to examine pathological changes in lungs. Wet/dry (W/D) ratios, myeloperoxidase activity, malondialdehyde concentrations and tumour necrosis factor-alpha (TNF-alpha) as well as interleukin 1 beta (IL-1beta) levels in lungs were measured. The pulmonary expression of nuclear factor kappaB (NF-kappaB) p65 was evaluated by Western blotting. Differences between the different groups were analysed by one-way analysis of variance (ANOVA).

RESULTS

The lung tissues from the saline + lipopolysaccharide group were significantly damaged, which were less pronounced in the erythropoietin + lipopolysaccharide group. The W/D ratio increased significantly in the saline + lipopolysaccharide group (5.75 +/- 0.22) as compared with the saline group (3.85 +/- 0.20) (P < 0.01), which was significantly reduced in the erythropoietin + lipopolysaccharide group (4.50 +/- 0.35) (P < 0.01). Myeloperoxidase activity and malondialdehyde levels increased significantly in the saline + lipopolysaccharide group compared with the saline group, which was reduced in the erythropoietin + lipopolysaccharide group. The TNF-alpha level of pulmonary tissue increased significantly in the saline + lipopolysaccharide group ((9.80 +/- 0.82) pg/mg protein) compared with the saline group ((4.20 +/- 0.42) pg/mg protein, P < 0.01). However, the increase of TNF-alpha level of pulmonary tissue was significantly reduced in the erythropoietin + lipopolysaccharide group ((6.50 +/- 0.66) pg/mg protein, P < 0.01). Similarly, pulmonary IL-1beta levels were elevated markedly in the saline + lipopolysaccharide group in contrast to the saline group, whereas the elevation was much less in the erythropoietin + lipopolysaccharide group. The nuclear localization of p65 increased markedly in the saline + lipopolysaccharide group and this enhancement of nuclear p65 expression was much less in the erythropoietin + lipopolysaccharide group.

CONCLUSION

Erythropoietin attenuates pulmonary inflammation and suppresses TNF-alpha and IL-1beta overproduction during acute endotoxaemia, which is partially mediated by inhibition of NF-kappaB.

Biodegradation of phthalate esters in compost-amended soil

In this study, we investigated the biodegradation of the phthalate acid esters (PAEs) di-n-butyl phthalate (DBP) and di-(2-ethyl hexyl) phthalate (DEHP) in compost and compost-amended soil. DBP (50 mg kg(-1)) and DEHP (50 mg kg(-1)) were added to the two types of compost (straw and animal manure) and subsequently added to the soil; they were tested as a single compound and in combination. Optimal PAE degradation in soil was at pH 7 and 30 degrees C. The degradation of PAE was enhanced when DBP and DEHP were simultaneously present in the soil. The addition of either of the two types of compost individually also improved the rate of PAE degradation. Compost samples were separated into fractions with various particle size ranges, which spanned from 0.1-0.45 to 500-2000 microm. We observed that the compost fractions with smaller particle sizes demonstrated higher PAE degradation rates. When the different compost fractions were added to soil, however, compost particle size had no significant effect on the rate of PAE degradation.

Anaerobic degradation of phenanthrene and pyrene in mangrove sediment

This study investigated the anaerobic degradation of the polycyclic aromatic hydrocarbons (PAHs) phenanthrene and pyrene in mangrove sediment from Taiwan. The anaerobic degradation of PAH was enhanced by the addition of acetate, lactate, pyruvate, sodium chloride, cellulose, or zero-valent iron. However, it was inhibited by the addition of humic acid, di-(2-ethylhexyl) phthalate (DEHP), nonylphenol, or heavy metals. Of the microorganism strains isolated from the sediment samples, we found that strain MSA3 (Clostridium pascui), expressed the best ability to biodegrade PAH. The inoculation of sediment with the strain MSA3 could enhance PAH degradation.

Impact of invasive fungal infection on outcomes of severe sepsis: a multicenter matched cohort study in critically ill surgical patients

Introduction

Fungal infection is increasingly common in critical illness with severe sepsis, but the influence of invasive fungal infection (IFI) on severe sepsis is not well understood. The aim of this study was to investigate the impact that IFI has on the outcomes of critically ill surgical patients with severe sepsis in China by means of matched cohort analysis; we also evaluated the epidemiologic characteristics of IFI in this population.

Methods

Records for all admissions to 10 university hospital surgical intensive care units (ICUs) from December 2004 to November 2005 were reviewed. Patients who met criteria for severe sepsis were included. IFI was identified using established criteria based on microbiologic or histological evidence. A matched cohort study was conducted to analyze the relationship between IFI and outcomes of severe sepsis.

Results

A total of 318 patients with severe sepsis were enrolled during the study period, of whom 90 (28.3%) were identified as having IFI. A total of 100 strains of fungi (58% Candida albicans) were isolated from these patients. Independent risk factors for IFI in patients with severe sepsis included mechanical ventilation (>3 days), Acute Physiology and Chronic Health Evaluation score, coexisting infection with both Gram-positive and Gram-negative bacteria, and urethral catheterization (>3 days). Compared with the control cohort, IFI was associated with increased hospital mortality (P < 0.001), high hospital costs (P = 0.038), and prolonged stay in the ICU (P < 0.001) and hospital (P = 0.020).

Conclusion

IFI is frequent in patients with severe sepsis in surgical ICUs and is associated with excess risk for hospital mortality, longer ICU and hospital stays, and greater consumption of medical resources.

Epidemiology of severe sepsis in critically ill surgical patients in ten university hospitals in China*

OBJECTIVES

To determine the occurrence rate, outcomes, and the characteristics of severe sepsis in surgical intensive care units in multiple medical centers within China and to assess the cost and resource use of severe sepsis in China.

DESIGN AND SETTING

Prospective, observational study of surgical intensive care unit patients at ten university hospitals in six provinces in China.

PATIENTS

All adult admissions in studied intensive care units from December 1, 2004, to November 30, 2005.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The criteria of severe sepsis were based on the American College of Chest Physicians/Society of Critical Care Medicine Consensus Conference definition. Analysis of data from 3,665 intensive care unit admissions identified 318 (8.68%) cases of severe sepsis, 64.8% of which were men. The median age (interquartile range) of patients with severe sepsis was 64 (47-74) yrs. Microbes had been isolated from 228 (71.7%) patients, including 171 (53.8%) with Gram-negative bacteria and 146 (45.9%) with Gram-positive bacteria. A total of 90 (22.0%) patients had invasive fungal infection, 20 (6.3%) of which had fungemia. The abdomen was the most common site of infections (72.3%), followed by lung (52.8%). The overall hospital mortality of severe sepsis was 48.7%. Risk factors for hospital mortality included age, chronic comorbidity of malignant neoplasm, Gram-positive bacterial infection, invasive fungal infection, admission Acute Physiology Score, and admission Sequential Organ Failure Assessment score of respiratory dysfunction and cardiovascular dysfunction. The median Therapeutic Intervention Scoring System-28 score was 43 (38-49). The mean hospital cost was $11,390 per patient and $502 per patient per day.

CONCLUSIONS

Severe sepsis is a common, expensive, and frequently fatal syndrome in critically ill surgical patients in China. Other than the microbiological patterns, the incidence, mortality, and major characteristics of severe sepsis in Chinese surgical intensive care units are close to those documented in developed countries.

Biodegradation of four phthalate esters in sludge

This study investigated the effects of ultrasonic pretreatment and various treatments on the aerobic degradation of four phthalic acid esters (PAEs) such as diethyl phthalate (DEP), benzyl butyl phthalate (BBP), di-n-butyl phthalate (DBP) and di-(2-ethyl hexyl)phthalate (DEHP) in sludge. The effect on PAE degradation of treating sludge with a 20 min sonication period at a power level of 0.1 W ml(-1) was evaluated. The degradation rates of the four PAEs were DBP>BBP>DEP>DEHP. Degradation rate constants (k(1)) and half-lives (t(1/2)) for the four PAEs (50 mg kg(-1)) ranged from 0.182 to 0.379 day(-1) and 1.8 to 3.8 days, respectively. The optimal pH for PAE degradation in sludge was 7.0 at 30 degrees C. PAE degradation was enhanced by the addition of yeast extract, brij 30 or brij 35 and inhibited by the addition of hydrogen peroxide. Our results show that a combination of ultrasonic pretreatment and biodegradation can effectively remove PAE from sludge.

Biodegradation of nonylphenol in soil

We investigated the effects of various factors (brij 30, brij 35, yeast extract, hydrogen peroxide and compost) on the aerobic degradation of nonylphenol (NP) in soil and characterized the structure of the microbial community in that soil. Residues of NP were measured using gas chromatography-mass spectrometry (GC-MS) and a change of microbial communities was demonstrated using denaturing gradient gel electrophoresis (DGGE). The results showed that Taichung sandy clay loam had higher NP degradation rate than Kaoshiung silty clay. The addition of compost, yeast extract (0.5 mg/l), brij 30 (55 microM), or brij 35 (91 microM) enhanced NP degradation, while the addition of hydrogen peroxide (1.0 mg/l) inhibited its degradation. We also found that the addition of various substrates changed the microbial community in the soils. Cytophaga sp. and Ochrobactrum sp. were constantly dominant bacteria under various conditions in the soil.

Plasma glucose levels and diabetes are independent predictors for mortality and morbidity in patients with SARS

AIMS

To investigate the relationships between a known history of diabetes and ambient fasting plasma glucose (FPG) levels with death and morbidity rates in patients with severe acute respiratory syndrome (SARS).

METHODS

In this retrospective analysis, the clinical and biochemical characteristics of 135 patients who had died from SARS, 385 survivors of SARS and 19 patients with non-SARS pneumonia were compared.

RESULTS

All patients were treated according to a predefined protocol. Before steroid treatment, the mean FPG level was significantly higher in the SARS group (deceased vs. survivors vs. non-SARS pneumonia group: 9.7 +/- 5.2 vs. 6.5 +/- 3.0 vs. 5.1 +/- 1.0 mmol/l, P < 0.01). In the SARS group, the percentage of patients with a known history of diabetes was significantly higher in the deceased patients than in the survivors (21.5% vs. 3.9%, P < 0.01). Among patients with no known history of diabetes and before commencement of steroid therapy, those who had hypoxaemia (SaO(2) < 93%) had higher FPG levels than those who did not have hypoxia in both the survivor (8.7 +/- 4.9 vs. 6.3 +/- 2.1 mmol/l, P < 0.001) and deceased (9.8 +/- 4.8 vs. 7.2 +/- 1.5 mmol/l, P < 0.001) groups. A known history of diabetes [odds ratio (OR) 3.0, 95% confidence interval (CI) 1.4, 6.3; P = 0.005] and FPG > or = 7.0 mmol/l before steroid treatment (OR 3.3, 95% CI 1.4, 7.7, P = 0.006) were independent predictors of death. During the course of the illness, FPG levels were negatively associated with SaO(2) (beta =-0.682 +/- 0.305, P = 0.025, general estimation equation model) in SARS patients. Survival analysis showed that FPG was independently associated with an increased hazard ratio (HR) of mortality (HR = 1.1, 95% CI 1.0, 1.1, P = 0.001) and hypoxia (HR = 1.1, 95% CI 1.0, 1.1, P = 0.002) after controlling for age and gender.

CONCLUSIONS

A known history of diabetes and ambient hyperglycaemia were independent predictors for death and morbidity in SARS patients. Metabolic control may improve the prognosis of SARS patients.

Biodegradation of nonylphenol in sewage sludge

We investigated the effects of various factors on the aerobic degradation of nonylphenol (NP) in sewage sludge. NP (5 mg/kg) degradation rate constants (k1) calculated were 0.148 and 0.224 day(-1) for the batch experiment and the bioreactor experiment, respectively, and half-lives (t(1/2)) were 4.7 and 3.1 days, respectively. The optimal pH value for NP degradation in sludge was 7.0 and the degradation rate was enhanced when the temperature was increased and when yeast extract (5 mg/l) and surfactants such as brij 30 or brij 35 (55 or 91 microM) were added. The addition of aluminum sulfate (200 mg/l) and hydrogen peroxide (1 mg/l) inhibited NP degradation within 28 days of incubation. Of the microorganism strains isolated from the sludge samples, we found that strain CT7 (identified as Bacillus sphaericus) manifested the best degrading ability.

Anaerobic degradation of nonylphenol in sludge

We investigated the effects of various factors on the anaerobic degradation of nonylphenol (NP) in sludge. NP (5 mg/l) anaerobic degradation rate constants were 0.029 1/day for sewage sludge and 0.019l/day for petrochemical sludge, and half-lives were 23.9 days and 36.5 days respectively. The optimal pH for NP degradation in sludge was 7 and the degradation rate was enhanced when the temperature was increased. The addition of yeast extract (5 mg/l) or surfactants such as brij 30 or brij 35 (55 or 91 microM) also enhanced the NP degradation rate. The addition of aluminum sulfate (200 mg/l) inhibited the NP degradation rate within 84 days of incubation. The high-to-low order of degradation rates was: sulfate-reducing conditions>methanogenic conditions>nitrate-reducing conditions. Sulfate-reducing bacteria, methanogen, and eubacteria are involved in the degradation of NP, sulfate-reducing bacteria being a major component of sludge.

Anaerobic degradation of diethyl phthalate, di-n-butyl phthalate, and di-(2-ethylhexyl) phthalate from river sediment in Taiwan

We investigated anaerobic degradation rates for three phthalate esters (PAEs), diethyl phthalate (DEP), di-n-butyl phthalate (DBP), and di-(2-ethylhexyl) phthalate (DEHP), from river sediment in Taiwan. The respective anaerobic degradation rate constants for DEP, DBP, and DEHP were observed as 0.045, 0.074, and 0.027 1/day, with respective half-lives of 15.4, 9.4, and 25.7 days under optimal conditions of 30 degrees C and pH7.0. Anaerobic degradation rates were enhanced by the addition of the surfactants brij 35 and triton N101 at a concentration of 1 critical micelle concentration (CMC), and by the addition of yeast extract. Degradation rates were inhibited by the addition of acetate, pyruvate, lactate, FeCl3, MnO2, NaCl, heavy metals, and nonylphenol. Our results indicate that methanogen, sulfate-reducing bacteria, and eubacteria are involved in the degradation of PAEs.

Degradation of nonylphenol by anaerobic microorganisms from river sediment

We investigated the degradation of nonylphenol monoethoxylate (NP1EO) and nonylphenol (NP) by anaerobic microbes in sediment samples collected at four sites along the Erren River in southern Taiwan. Anaerobic degradation rate constants (k1) and half-lives (t1/2) for NP (2 microg/g) ranged from 0.010 to 0.015 1/day and 46.2 to 69.3 days respectively. For NP1EO (2 microg/g), the ranges were 0.009-0.014 1/day and 49.5-77.0 days respectively. Degradation rates for NP and NP1EO were enhanced by increasing temperature and inhibited by the addition of acetate, pyruvate, lactate, manganese dioxide, ferric chloride, sodium chloride, heavy metals, and phthalic acid esters. Degradation was also measured under three anaerobic conditions. Results show the high-to-low order of degradation rates to be sulfate-reducing conditions > methanogenic conditions > nitrate-reducing conditions. The results show that sulfate-reducing bacteria, methanogen, and eubacteria are involved in the degradation of NP and NP1EO, with sulfate-reducing bacteria being a major component of the river sediment.

Biodegradation of phthalate esters by two bacteria strains

In this study two aerobic phthalic acid ester (PAE) degrading bacteria strains, DK4 and O18, were isolated from river sediment and petrochemical sludge, respectively. The two strains were found to rapidly degrade PAE with shorter alkyl-chains such diethyl phthalate (DEP), dipropyl phthalate (DPrP), di-n-butyl phthalate (DBP), benzylbutyl phthalate (BBP) and diphenyl phthalate (DPP) are very easily biodegraded, while PAE with longer alkyl-chains such as dicyclohexyl phthalate (DCP) and dihexyl phthalate (DHP) and di-(2-ethylhexyl) phthalate (DEHP) are poorly degraded. The degradation rates of the eight PAEs were higher for strain DK4 than for strain O18. In the simultaneous presence of strains DK4 and O18, the degradation rates of the eight PAEs examined were enhanced. When the eight PAEs were present simultaneously, degradation rates were also enhanced. We also found that PAE degradation was delayed by the addition of nonylphenol or selected polycyclic aromatic hydrocarbons (PAHs) at a concentration of 1 microg/g in the sediment. The bacteria strains isolated, DK4 and O18, were identified as Sphigomonas sp. and Corynebacterium sp., respectively.

Protective effects of early treatment with propofol on endotoxin-induced acute lung injury in rats

BACKGROUND

To investigate the effects of propofol administration on acute lung injury in endotoxin-induced shock in rats.

METHODS

Seventy-six male Wistar rats were randomly assigned to one of five groups: (i) saline control; (ii) endotoxin alone (receiving lipopolysaccharide (LPS) 8 mg kg(-1) i.v.); (iii) pretreatment with propofol 1 h before LPS; (iv) simultaneous treatment with propofol and LPS; (v) post-treatment with propofol 1 h after LPS. During the 5 h after LPS injection, survival rates were recorded. Lung tissue was sampled to measure values of nitrite/nitrates (NO(2-)/NO(3-)) and tumour necrosis factor (TNF)-alpha in bronchoalveolar lavage (BAL) fluid, and wet-to-dry lung weight ratio, pulmonary permeability index, BAL protein and expression of inducible nitric oxide synthase (iNOS) and nitrotyrosine (NT).

RESULTS

Compared with the endotoxaemic group, both the pre- and simultaneous treatment groups showed significantly improved 5 h survival rates, and attenuated endotoxin-induced increased BAL fluid NO(2-) /NO(3-) and TNF-alpha, iNOS mRNA and NT expression in lung tissue, and decreased pulmonary microvascular permeability. These beneficial effects were blunted in the post-treatment group.

CONCLUSIONS

These findings indicate that early administration of propofol may provide protective effects against endotoxin-induced acute lung injury.

Biodegradation of nonylphenol in river sediment

We investigated the biodegradation of nonylphenol monoethoxylate (NP1EO) and nonylphenol (NP) by aerobic microbes in sediment samples collected at four sites along the Erren River in southern Taiwan. Aerobic degradation rate constants (k1) and half-lives (t1/2) for NP (2 microg g(-1)) ranged from 0.007 to 0.051 day(-1) and 13.6 to 99.0 days, respectively; for NP1EO (2 microg g(-1)) the ranges were 0.006 to 0.010 day(-1) and 69.3 to 115.5 days. Aerobic degradation rates for NP and NP1EO were enhanced by shaking and increased temperature, and delayed by the addition of Pb, Cd, Cu, Zn, phthalic acid esters (PAEs), and NaCl, as well as by reduced levels of ammonium, phosphate, and sulfate. Of the microorganism strains isolated from the sediment samples, we found that strain JC1 (identified as Pseudomonas sp.) expressed the best biodegrading ability. Also noted was the presence of 4'-amino-acetophenone, an intermediate product resulting from the aerobic degradation of NP by Pseudomonas sp.

Occurrence and microbial degradation of phthalate esters in Taiwan river sediments

Concentrations and microbial degradation rates were measured for eight phthalate esters (PAEs) found in 14 surface water and six sediment samples taken from rivers in Taiwan. The tested PAEs were diethyl phthalate (DEP), dipropyl phthalate (DPP), di-n-butyl phthalate (DBP), diphenyl phthalate (DPhP), benzylbutyl phthalate (BBP), dihexyl phthalate (DHP), dicyclohexyl phthalate (DCP), and di-(2-ethylhexyl) phthalate (DEHP). In all samples, concentrations of DEHP and DBP were found to be higher than the other six PAEs. DEHP concentrations in the water and sediment samples ranged from ND to 18.5 microg/l and 0.5 to 23.9 microg/g, respectively; for DBP the concentration ranges were 1.0-13.5 microg/l and 0.3-30.3 microg/g, respectively. Concentrations of DHP, BBP, DCP and DPhP were below detection limits. Under aerobic conditions, average degradation half-lives for DEP, DPP, DBP, DPhP, BBP, DHP, DCP and DEHP were measured as 2.5, 2.8, 2.9, 2.6, 3.1, 9.7, 11.1 and 14.8 days, respectively; under anaerobic conditions, respective average half-lives were measured as 33.6, 25.7, 14.4, 14.6, 19.3, 24.1, 26.4 and 34.7 days. In other words, under aerobic conditions we found that DEP, DPP, DBP, DPhP and BBP were easily degraded, but DEHP was difficult to degrade; under anaerobic conditions, DBP, DPhP and BBP were easily degraded, but DEP and DEHP were difficult to degrade. Aerobic degradation rates were up to 10 times faster than anaerobic degradation rates.

Anaerobic biodegradation of polycyclic aromatic hydrocarbon in soil

Known concentrations of phenanthrene, pyrene, anthracene, fluorene and acenapthene were added to soil samples to investigate the anaerobic degradation potential of polycyclic aromatic hydrocarbon (PAH). Consortia-treated river sediments taken from known sites of long-term pollution were added as inoculum. Mixtures of soil, consortia, and PAH (individually or combined) were amended with nutrients and batch incubated. High-to-low degradation rates for both soil types were phenanthrene > pyrene > anthracene > fluorene > acenaphthene. Degradation rates were faster in Taida soil than in Guishan soil. Faster individual PAH degradation rates were also observed in cultures containing a mixture of PAH substrates compared to the presence of a single substrate. Optimal incubation conditions were noted as pH 8.0 and 30 degrees C. Degradation was enhanced for PAH by the addition of acetate, lactate, or pyruvate. The addition of municipal sewage or oil refinery sludge to the soil samples stimulated PAH degradation. Biodegradation was also measured under three anaerobic conditions; results show the high-to-low order of biodegradation rates to be sulfate-reducing conditions > methanogenic conditions > nitrate-reducing conditions. The results show that sulfate-reducing bacteria, methanogen, and eubacteria are involved in the PAH degradation; sulfate-reducing bacteria constitute a major component of the PAH-adapted consortia.

Data compression for arterial pulse waveform

The arterial pulse possesses important clinical information in traditional Chinese medicine. It is usually recorded for a long period of time in the applications of telemedicine and PACS systems. Due to the huge amount of data, by recognizing the strong correlation between successive beat patterns in arterial pulse waveform sequences, a novel and efficient data compression scheme based mainly on pattern matching is introduced. The simulation results show that our coding scheme can achieve a very high compression ratio and low distortion for arterial pulse waveform.

Ventral burn in rats: an experimental model for intravital microscopic study of microcirculation

A novel technique of application of controlled ventral scald burn to rodent, whose back is inaccessible because of preburn preparation, is described. Boiling water is applied across a polyethylene membrane that partially envelops the subject. The technique is simple, economical, reproducible and allows intravital microscopic study of microcirculation in a remote muscular bed before and after burn injury.