[Two-stage Inhibition Effects of Burkholderia sp. Y4 Application on Cadmium Uptake and Transport in Wheat].

In order to evaluate the feasibility of using Burkholderia sp. Y4 as a cadmium （Cd）-reducing bacterial agent in contaminated wheat fields， the changes in the rhizosphere soil microbial community and Cd available state， as well as the content and transport characteristics of Cd in the wheat root， basal node， internode， and grain under the treatment of strain Y4 were tested using microbial high-throughput sequencing， step-by-step extraction， subcellular distribution， and occurrence analyses. The results showed that root application of strain Y4 significantly reduced the root and grain Cd content of wheat by 7.7% and 30.3%， respectively， compared with that in the control treatment. The Cd content and Cd transfer factor results in wheat vegetative organs showed that strain Y4 reduced the Cd transfer factor from basal node to internode by 79.3%， and Cd content in the wheat internode stem also decreased by 50.9%. The study of Cd occurrence morphology showed that strain Y4 treatment increased the proportion of residual Cd in roots and basal ganglia， decreased the contents of inorganic and water-soluble Cd in roots， and increased the content of residual Cd in basal ganglia. Further examination of the subcellular distribution of Cd showed that the Cd content in root cell walls and basal ganglia cell fluid increased by 21.3% and 98.2%， respectively， indicating that the Cd fixation ability of root cell walls and basal ganglia cell fluid was improved by the strain Y4 treatment. In the rhizosphere soil， it was found that the microbial community structure was changed by strain Y4 application. Under the Y4 treatment， the relative abundance of Burkholderia increased from 9.6% to 11.5%， whereas that of Acidobacteriota decreased. Additionally， the relative abundance of Gemmatimonadales， Pseudomonadales， and Chitinophagales were also increased by strain Y4 treatment. At the same time， the application of strain Y4 increased the pH value of rhizosphere soil by 8.3%. The contents of exchangeable Cd， carbonate-bound Cd， and iron-manganese oxide-bound Cd in the soil decreased by 44.4%， 21.7%， and 15.9%， respectively， whereas the proportion of residual Cd reached 53.6%. Root application of strain Y4 increased the contents of nitrate nitrogen and ammonium nitrogen in the soil by 22.0% and 21.4%， respectively， and the contents of alkaline nitrogen also increased to a certain extent. In conclusion， the root application of strain Y4 not only improved soil nitrogen availability but also inhibited Cd transport and accumulation from contaminated soil to wheat grains in a "two-stage" manner by reducing Cd availability in rhizosphere soil and improving Cd interception and fixation capacity of wheat roots and basal nodes. Therefore， Burkholderia Y4 has application potential as a Cd-reducing and growth-promoting agent in wheat.

[Effects of Burkholderia sp. Y4 on Cadmium Damage and Uptake in Rice Seedlings].

In order to investigate the effects of Burkholderia sp. Y4 on rice seedlings under cadmium (Cd) stress, seed germination and vermiculite culture experiments were conducted using low Cd-accumulation xiangzaoxian 24 (X24) and high Cd-accumulation Tyou 705 (T705) varieties. The effects of Burkholderia sp. Y4 on rice growth, oxidative damage caused by Cd, and Cd accumulation were studied. Additionally, the Cd2+ flux rates in the elongation zone of rice roots under Burkholderia sp. Y4 application were detected using non-invasive micro-test technology. Burkholderia sp. Y4 alleviated the inhibition effect of Cd on rice seed germination by 13.8%. After inoculation with Burkholderia sp. Y4 for 7 d, the length of rice roots and buds increased by 83.3% and 12.2%, and their dry weight increased by 56.8% and 12.5%, respectively; those in the 10 d Y4 inoculation group increased by 28.6% and 20.0% in length and by 113.2% and 46.0% in dry weight, respectively. Burkholderia sp. Y4 inoculation also alleviated rice oxidative stress damage caused by Cd. The application of strain Y4 significantly reduced the content of the oxidative damage product malondialdehyde (MDA) in the shoots and roots of rice seedlings by 21.5% and 16.9%, respectively. Under Burkholderia sp. Y4 inoculation, the significant changes in antioxidant enzyme SOD and CAT activities caused by Cd stress disappeared in rice roots; those in shoots also decreased from 176.9% and 74.8% to 53.3% and 21.5%, respectively. Conversely, Burkholderia sp. Y4 inhibited Cd uptake by rice seedlings with different genotypes, including the low Cd-accumulation variety X24 and high Cd-accumulation variety T705. The root application of strain Y4 significantly reduced Cd accumulation in the shoots and roots of rice seedlings by 79.2% and 62.7% in T705 and by 57.3% and 24.1% in X24, respectively. The Cd2+ flux rate of high Cd-accumulation variety T705 was significantly higher than that of low Cd-accumulation variety X24. Under Burkholderia sp. Y4 inoculation, the yellow membrane was formed on the root surface of rice seedlings, and the Cd2+ flux rate in the elongation zone of T705 and X24 roots decreased by 36.0% and 35.0% in 3-day-old seedlings, as well as by 44.6% and 24.9% in 10-day-old seedlings, respectively. In conclusion, Burkholderia sp. Y4 inoculation inhibited the toxic effects of Cd on rice seedling growth through alleviating oxidative stress and damage caused by Cd. Furthermore, the root application of Burkholderia sp. Y4 effectively decreased the Cd2+ flux rate in the elongation zone of roots to inhibit the Cd uptake and accumulation in roots and shoots of rice seedlings. This study provides theoretical basis and data support for the application of Burkholderia sp. Y4 as a Cd-reducing and growth-promoting agent for rice in contaminated farmland.

Active targeted Janus nanoparticles enable anti-angiogenic drug combining chemotherapy agent to prevent postoperative hepatocellular carcinoma recurrence.

Surgery is one of the main effective strategies for the treatment of solid tumors, but high postoperative recurrence is also the main cause of death in current cancer therapy. The prevention of postoperative hepatocellular carcinoma (HCC) recurrence is a clinical problem that needs to be solved urgently. At present, there are still some problems to be solved, such as, how to achieve free drugs to target the site of surgical resection; develop a strategy for the simultaneous administration of multiple drugs to inhibit postoperative recurrence; and provide the appropriate animal model that mimics the process of postoperative HCC recurrence. In this study, we used a facile and reproducible method to successfully prepare amphiphilic Janus nanoparticles (JNPs). In order to improve targeting of the JNPs to residual HCC cells after surgery, we modified the side of gold nanorods (GNRs) with lactobionic acid (LA), thus creating LA-JNPs. This provided an active and targeted co-delivery system for hydrophilic and hydrophobic drugs in separate rooms, thus avoiding mutual effects. Next, we established two models to simulate postoperative HCC recurrence: a subcutaneous postoperative recurrence model based on patient-derived tumor xenograft (PDX) tissues and a postoperative recurrence model of orthotopic HCC. By applying these models, the enhanced permeability and retention effect (EPR) based tumor targeting and LA based active targeting can jointly promote the enrichment and uptake of JNPs at tumor site. LA-JNPs represented an efficient targeting system for the co-delivery of Sorafenib/Doxorubicin with an optimized anti-recurrence effect and significantly improved the survival of mice during treatment for postoperative recurrence.

[Isolation and Identification of the Plant Endophyte R-13 and Its Effect on Cadmium Accumulation in Solanum nigrum L.]

The combination of endophytes and hyperaccumulator plants can significantly improve the efficiency of heavy metal phytoremediation in contaminated soil. A plant endophyte named Herbaspirillum R-13 was isolated from rice roots in a cadmium (Cd) contaminated paddy field. This strain exhibited a strong tolerance to Cd2+ and could grow on a solid medium with a Cd2+ concentration of 300 mg·kg-1. The R-13 strain was able to produce siderophores and Indole acetic acid (IAA), through color reactions. In addition, Pikovskaya's and Ashby's solid medium tests showed that the R-13 strain had a lower capacity for dissolving phosphorus but a higher capacity for fixing nitrogen. In the pot experiment, high-throughput sequencing technology was used to track the colonization of the R-13 strain in Solanum nigrum L. roots. Three days after inoculation, the relative abundance of Herbaspirillum in the root of Solanum nigrum L. had increased by 201.88% compared to the blank control (CK) and after two inoculations, the relative abundance of Herbaspirillum in the root of Solanum nigrum L. had increased by 1182.44% compared to CK. The relative abundance of Herbaspirillum in the root of Solanum nigrum L. began to decrease significantly from 5 days after inoculation. Inoculation with 20 mL·pot-1 of R-13 fermentation broth resulted in no significant effects on the Cd content of roots, stems, leaves, or fruits of S. nigrum L. With 40 mL·pot-1 of fermentation broth, the Cd content of vegetative organs and fruits was significantly increased. When it reached 200 mL·pot-1, the Cd content of vegetative organs was the highest, with Cd concentrations in the roots, stems, leaves, and fruits increasing by 84.42%, 43.67%, 64.06%, and 20.29%, respectively. In conclusion, root inoculation with endophytic Herbaspirillum R-13 can significantly increase the relative content of Herbaspirillum in the root system and enhance Cd absorption of S. nigrum L. Therefore, this strain has excellent prospects for application in the phytoremediation of soil contaminated with Cd.

[Foliar Application of L-Cysteine: Effects on the Concentration of Cd and Mineral Elements in Rice].

To evaluate the feasibility of applying L-cysteine (L-Cys) as a foliar conditioner for Cd reduction in rice, a field experiment was conducted to investigate the concentration of Cd and mineral elements in rice after the foliar application of L-Cys. The variation in Cd distribution and morphology in key rice organs was examined to study the Cd reduction mechanisms of spraying L-Cys on rice. The results showed that foliar application of L-Cys at the rice-flowering stage significantly decreased Cd concentration in grains, in a concentration dependent manner, without inhibiting the accumulation of mineral elements Ca, Mg, K, Mn, and Zn. With a 10 mmol ·L-1 L-Cys application, Cd concentration in rice grains decreased by 59.2%, to below 0.2 mg ·kg-1, which is the maximum safety limit in China. Foliar application of L-Cys also inhibited Cd accumulation in rice vegetative organs, including rachises, first nodes, neck-panicles, flag leaves, second internodes, second nodes, second leaves, stalks, and roots (58.3%, 56.0%, 62.7%, 67.0%, 59.3%, 61.5%, 60.2%, 54.9%, and 50.3%, respectively). After transfer factor calculation, first nodes were found to be the key organ for Cd blocking in rice. The application of L-Cys increased Cd transfer from flag leaves and second internodes to first nodes (105.4% and 45.8%, respectively), but decreased Cd transfer from first nodes up to neck-panicles (27.5%). In rice first nodes, the concentrations of Cd in the inorganic, water soluble, and residue states were all lower following L-Cys application, and the proportion of residual Cd increased to 94.4%. Therefore, foliar application of L-Cys significantly inhibited Cd transport and accumulation in rice grains, by decreasing the Cd concentrations of various vegetative organs and improving Cd interception in the first nodes. This is a promising way to produce rice with lower Cd concentrations and normal mineral element concentrations in Cd-contaminated paddy fields.

[Mechanism of S-allyl-L-cysteine Alleviating Cadmium Stress in Seedling Roots and Buds of Rice Seedlings].

Cd has toxic effects on rice seed germination and plant growth, which may eventually lead to decreased yield and excessive Cd content in rice grains. The potential mechanism of S-allyl-L-cysteine (SAC), a natural sulfur compound derived from garlic extract, in alleviating Cd2+ stress in young roots and buds of rice seedlings was studied by a seed germination experiment. "Zhong zao 35", one of the main rice varieties in Southern China, was selected as the test material. Firstly, the alleviating effect of SAC on Cd2+ stress in rice seedling roots and buds was studied. Following this, the physiological mechanism of Cd2+ stress alleviation by SAC was examined based on the expression of the Cd transporter coding gene using real-time fluorescent quantitative PCR. The results showed that when the Cd2+ stress concentration reached 50 µmol·L-1, the young roots and buds of rice seedlings were significantly inhibited, and when the SAC concentration reached 200 µmol·L-1, Cd2+ stress was significantly alleviated. Compared to a Cd2+ stress treatment group, the total root length, surface area, and volume of young roots was increased by 173.5%, 65.52%, and 37.04%, respectively; CAT and SOD activity in young roots and buds was increased by 212.42% and 110.76%, and 31.41% and 47.31%, respectively; MDA and GSH content was decreased by 43.09% and 34.12%, and 33.97% and 35.74%, respectively; and Cd content was decreased by 35.91% and 28.86%, respectively. The results of quantitative real-time PCR showed that the relative expression levels of OsNramp5 and OsHMA2 were significantly reduced by 33.38% and 34.99% compared with the Cd2+ stress group, respectively. However, the relative expression level of OsHMA3 was significantly increased by 33.96%. From the above experimental results, the main mechanism by which SAC reduces Cd2+ stress in the young roots and buds of rice is via the regulation of Cd transporter-encoding genes, reducing Cd2+ transport to young roots and buds, and increasing transport to vacuoles.

Rice vegetative organs alleviate cadmium toxicity by altering the chemical forms of cadmium and increasing the ratio of calcium to manganese.

Altering Cd chemical form is one of the mechanisms to alleviate Cd toxicity in rice plant. Field experiments were carried out in this study to investigate the potential of rice vegetative organs in altering Cd into insoluble chemical forms in the natural environment. Experimental results showed that more than 80% of Cd in rice roots existed in the insoluble forms. Uppermost nodes altered Cd into insoluble form preferentially and generally had higher content of insoluble Cd than other organs. Rachises displayed a slow increasing trend in soluble Cd when total Cd in roots was less than 1.8 mg kg-1. However, when Cd content in roots exceeded 2.8 mg kg-1, the ratio of insoluble to soluble Cd remained stable at 85:15 in rachises and roots, and at 75:25 in uppermost nodes and flag leaves. Cd concentration in grains was greatly lower than that in vegetative organs, and closely correlated with the content of soluble Cd in rachises (r = 0.991**) as well as in uppermost nodes. Soluble Cd in the uppermost nodes displayed a much lower mobility than that in other organs. Accumulation of soluble Cd was always companied by decrease of Ca and increase of Mn in roots, uppermost nodes and rachises. A small increase of soluble Cd from 0.05 to 0.1 mg kg-1 caused a sharp decline of Ca:Mn ratio in roots and rachises. Roots and nodes had much higher Ca:Mn ratio than rachises when soluble Cd was less than 0.5 mg kg-1 in them. These results indicate that vegetative organs have a great potential to alter more than 75% Cd into insoluble forms and increasing Ca:Mn ratio may be another way to alleviate Cd toxicity by establishing new ionic homeostasis in rice plants.

First report on isolation of methyl gallate with antioxidant, anti-HIV-1 and HIV-1 enzyme inhibitory activities from a mushroom (Pholiota adiposa).

In this study, a compound with antioxidant and anti-HIV activities designated as HEB was first isolated from the edible mushroom Pholiota adiposa by extraction with ethanol and ethyl acetate. HEB was then purified by high performance liquid chromatography (HPLC) and identified to be methyl gallate (C8H8O5, 184.1 Da) based on data from its mass spectrum (MS) and nuclear magnetic resonance (NMR) spectrum. HEB displayed strong antioxidant potency in inhibiting, at 1.36 mM concentration, erythrocyte hemolysis and scavenging DPPH radicals and superoxide anion (O2(-)) by 82.4%, 85.6% and 71.4%, respectively. Besides exhibiting a low cytotoxicity, compound HEB demonstrated significant anti-HIV activity in that it inhibited HIV-1 replication in TZM-BL cells infected by pseudovirus with an IC50 value of 11.9 µM. Further study disclosed that HEB inhibited the viral entry process and activities of key enzymes essential for the HIV-1 life cycle. HEB inhibited HIV-1 reverse transcriptase and integrase activities with an IC50 value of 80.1 µM and 228.5 µM, respectively, and at 10 mM concentration inhibited HIV-1 protease activity by 17.1% which was higher than that achieved by the positive control pepstatin A. Interestingly, this study first revealed that H2O2 stimulation not only activated cell oxidative stress responses, but also accelerated HIV-1 long terminal repeat (LTR) promotion in TZM-BL cells, which was significantly reduced by HEB from 18.2% to about 2%. It implied a direct relationship between the antioxidant and anti-HIV activities of the natural active constituent HEB. Nuclear transcription factor kappa B (NF-κB) signal pathways plays an important role in oxidative stress responses. Meanwhile, there is κB target sequence in HIV promoter LTR which is significant for virus replication and gene expression. In this study, Western Blot assay showed that HEB could inhibit the activation of NF-κB signal pathway stimulated by H2O2 in mouse spleen cells through suppressing NF-κB (p65) translocation into nucleus and NF-kappa-B inhibitor (IκB) degradation in cytoplasm. In summary, the antioxidant HEB from P. adiposa could inhibit HIV-1 replication through multiple target sites. The data suggest that natural antioxidant compounds might have a potential for treatment of AIDS.

Effects of adenosine extract from Pholiota adiposa (Fr.) quel on mRNA expressions of superoxide dismutase and immunomodulatory cytokines.

Pholiota adiposa is a kind of edible mushroom which has long been known for its health care applications. To reveal the exact mechanism of its protective functions in humans, in this study we isolated and identified the active compound PB3 of P. adiposa for the first time by a combination of chromatography techniques, including NKA macroporous resin and Sephadex G-15. PB3, with molecular mass of 267.2 Da and molecular formula of C10H13N5O4 discovered by mass spectrum (MS) was identified to be adenosine. Mice were injected intraperitoneally with purified fraction PB3. Seven days after injection, we found a 1.5-fold increase of IL10 at the mRNA level, while a down regulated expression of IL-2, IL-6 and IFN-γ to 49.0%, 56.9% and 73.4%, respectively, was detected in spleen by real-time quantitative PCR. What's more, SOD expression level was significantly increased by 1.6-fold compared to control. Fraction PB3 displayed anti-inflammatory potency and heightened SOD activity on the transcriptional level, which could be considered of further pharmaceutical or medication value.

Isolation and identification of a novel polysaccharide-peptide complex with antioxidant, anti-proliferative and hypoglycaemic activities from the abalone mushroom.

A novel antioxidant polysaccharide-peptide complex LB-1b from the fruiting bodies of the edible abalone mushroom (Pleurotus abalonus) was purified and identified. The structural characteristic of LB-1b was identified by FTIR (Fourier-transform IR), 13C NMR and 1H NMR spectroscopy. LB-1b is a polysaccharide-peptide complex that contains glucose, rhamnose, glucuronic acid and galactose in the molar ratio of 22.4:1:1.7:1.6 and the N-terminal sequence of its peptide moiety has also been determined. The N-terminal amino acid sequence of LB-1b, IPKERKEFQQAQHLK, showed some resemblance to antioxidant enzymes. LB-1b exhibited high antioxidant activity in erythrocyte haemolysis in vitro and the anti-proliferative activity towards hepatoma HepG2 cells and breast cancer MCF7 cells with an IC50 of 24 and 14 µM respectively. LB-1b also demonstrated hypoglycaemic activity in drug-induced diabetic mice and anti-HIV-1 RT (reverse transcriptase) with an IC50 value of 12.5 µM.

Isolation of a polysaccharide with antiproliferative, hypoglycemic, antioxidant and HIV-1 reverse transcriptase inhibitory activities from the fruiting bodies of the abalone mushroom Pleurotus abalonus.

OBJECTIVE: The intent of this study was to purify and characterize a polysaccharide named LA from the fruiting bodies of the edible mushroom Pleurotus abalones. METHODS: The 120-kDa polysaccharide was obtained by extraction with boiling water, ethanol precipitation, ion exchange chromatography on Diethylaminoethyl-cellulose and gel filtration on Sephadex G-200. KEY FINDINGS: The LA was composed of glucose, rhamnose, glucuronic acid, xylose, galactose and arabinose in the molar ratio of 26.3:2.7:1:1.4:1.8:1.2. The FITR and 1H-NMR spectrum of LA disclosed that it was a saccharide with an α-configuration. Its 13C-NMR spectrum revealed that its main chain was [→6)-α-D-Gly(1→]n. The LA exhibited antioxidant activities, especially in scavenging 1,1- diphenyl-2-picryl-hydrazyl radicals and hydroxyl radicals. It manifested antiproliferative activity towards breast cancer MCF7 cells with an IC50 of 3.7 µm, and also exerted some antiproliferative activity against HepG2 cells. It manifested a hypoglycemic action on diabetic mice. It inhibited HIV-1 reverse transcriptase with an IC50 of 8.7 × 10(-2) µm. CONCLUSIONS: The polysaccharide from the abalone mushroom.

[The effect of up-regulation of MHC class I chain-related antigen A expression by dendritic cells on activity of NK cells].

AIM: To observe whether MHC class I chain-related antigen A (MICA) was expressed on monocytes, immature dendritic cells (iDCs), and mature dendritic cells (mDCs), and to study effect of up-regulation of MICA expression by DCs on biologic activity of NK cells. METHODS: MICA expression on monocytes, iDCs, or mDCs stimulated with LPS, TNF-α, CD40L, IL-15 or IFN-α was detected by flow cytometry. Next CD69 expression, degranuation, and IFN-γ production of NK cells stimulated with MICA-positive mDCs were analyzed. Lastly recombinant NKG2D/Fc fusion protein and anti-IL-12 monoclonal antibody was respectively added into culture systems to analyze whether these reagents affected the interaction between DCs and NK cells. RESULTS: MICA was not expressed on monocytes, and expressed on iDCs at low level. LPS, TNF-α, CD40L had no influences on MICA expression on mDCs, but IFN-α, IL-15 up-regulated MICA expression on mDCs. MICA-positive mDCs promoted CD69 expression, IFN-γ production, and killing K562 cells by NK cells. NKG2D/Fc inhibited both cytotcoxicity and IFN-γ secretion, whereas IL-12 antibody only inhibited IFN-γ secretion of NK cells. CONCLUSION: MICA expression on DCs is regulated by relevant factors in microenvironment. DCs with high level of MICA expression can up-regulate biologic activity of NK cells.

[The influence of changes in the levels of calcitonin gene-related peptide and neuropeptide Y on cardiac function of severe burn patients during shock stage].

OBJECTIVE: To investigate the influence of the changes in the levels of calcitonin gene-related peptide (CGRP) and neuropeptide Y (NPY) on cardiac function of severe burn patients during shock stage. METHODS: Sixty severe burn patients with total burn surface area larger than 30% were enrolled as experiment group (E group) , and they received fluid resuscitation and debridement during shock stage. Sixty healthy volunteers were enrolled as control group (C group). The changes in the plasma level of CGRP, NPY and cTnT in E and C groups were observed at 1, 3, 6, 12, 24, 48 post-burn hours (PBH). The correlation among the CGRP, NPY and cTnT in the C group were analyzed. RESULTS: At 3 PBH, the plasma level of CGRP in E group (28 +/- 6) ng/L was lower than that in C group (55 +/- 7) ng/L , and it reached the lowest level at 12 PBH (15 +/- 4)ng/L . It was still lower than that in C group at 48 PBH (P < 0.05). The levels of NPY and cTnT in E group were significantly increased at 1PBH [(136 +/- 20) ng/L, (0.41 +/- 0.08) microg/L] compared with that in C group[ (86 +/- 13) ng/L, (0.16 +/- 0.06) microg/L], peaking at 12PBH [(189 +/- 31) ng/L, (1.78 +/- 0. 47) microg/L], and remaining higher than those in C group at 48PBH. There exhibited obvious negative correlation between the changes in the level of CGRP and cTnT ( r = -0.76, P < 0.01), while obvious positive correlation was found between the changes in level of NPY and cTnT ( r = 0.79, P < 0.01). CONCLUSION: The decrease in CGRP level and the increase in NPY level might play important roles in myocardial injury during shock stage of severe burn patients.

p38 mitogen-activated protein kinase inhibition attenuates burn-induced liver injury in rats.

This study was made to evaluate the effect of SB203580, a specific p38 MAP kinase inhibitor, on burn-induced hepatic injury as well as the activation of nuclear factor (NF)-kappaB in severely burned rats. Sprague-Dawley rats were divided into three groups: (1) sham group, rats underwent sham burn; (2) burn group, rats given third-degree burns over 30% total body surface area (TBSA) and treated with vehicle plus lactated Ringer solution for resuscitation 4 ml/(kg% TBSA); and (3) burn plus SB203580 group, rats given burn injury and fluid resuscitation plus SB203580 (10 mg/kg i.v., 15 min and 12 h after burn). Hepatocellular injury (measured by serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT)) and hepatocellular function (determined by the indocyanine green dye retention rate (ICG R15)) were assessed at 24 h post-burn. Liver histologic changes were also analyzed. Burn trauma resulted in increased serum aminotransferases concentrations, decreased ICG R15, elevated serum tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta levels and hepatic TNF-alpha and IL-1beta mRNA expressions, and worsen histologic condition. The level of Nuclear Factor (kappa) inhibitor (IkappaBalpha) in liver was decreased and DNA-binding activity of Nuclear Factor-kappaB (NF-kappaB) was increased after thermal injury. p38 MAP kinase was more significantly activated in liver harvested from burn rats than from shams. SB203580 inhibited the activation of p38 MAP kinase, reduced the levels of TNF-alpha and IL-1beta, and prevented burn-mediated liver injury. Both the IkappaBalpha level and NF-kappaB activity in the liver following burns was not affected by administration with SB203580. These findings suggest that (1) p38 MAP kinase activation is one important aspect of the signaling event that may mediate the release of TNF-alpha and IL-1beta and contributes to burn-induced liver injury and (2) p38 MAP kinase does not influence the activation of NF-kappaB directly in the liver of severely burned rats.

[The modulating role of p38 mitogen-activated protein kinase in the expression of tumor necrosis factor-alpha in hepatic cells and its role in hepatic injury in severely burned rats].

OBJECTIVE: To investigate The modulating role of p38 mitogen-activated protein kinase (MAPK) in the expression of tumor necrosis factor-alpha in hepatic cells and its role in hepatic injury in severely burned rats. METHODS: Twenty-four adult healthy male SD rats were randomly divided into three groups (8 rats in each group): sham group, burn group, and burn with SB203580 group. A rat model of full-thickness burn injury covering 30% total body surface area (TBSA) was reproduced. The specific inhibitor of p38MAPK (SB203580 in 10 mg/kg) was given to the rats in the burn with SB203580 group at 15 minutes and 12 hours after burn. The serum levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured at 24 postburn hours (PBHs). The TNF-alpha mRNA expression in the liver was determined by real-time reverse transcription polymerase chain reaction, and the expression levels of p38MAPK and phosphor-p38MAPK in the liver were determined by Western blot analysis. RESULTS: The serum levels of AST and ALT, and the expression of TNF-alpha mRNA in liver cells were significantly higher in burn group than those in sham and SB203580 groups (P < 0.05 or 0.01), but there was no difference between the two latter groups. It was indicated by Western blot results that there was no difference of p38MAPK expression in rat liver among the three groups (P > 0.05). The phospho-p38MAPK expression ratio among sham, burn and burn with SB203580 groups was 1.00:3.90:1.10. The phospho-p38MAPK expression was significantly lower in burn with SB203580 group than that in burn group (P < 0.01), but there was no significant difference compared with that in sham group (P > 0.05). CONCLUSION: The postburn activated p38MAPK in rat liver after severe burn injury enhances the expression of TNF-alpha mRNA and participates in the development of postburn hepatic injury.

Gunpowder explosion burns in fireworks factory: causes of death and management.

The mortality rate of gunpowder explosion burns from fireworks factory accidents was high. The aim of this study was to evaluate the impact of different managements on outcome of these burns patients and to optimize treatment measures and decrease the morbidity and mortality. During the period from January 1987 to December 1999 in our center, 44 patients burned in gunpowder explosions died. Fifty sex-, age-, TBSA- and full-thickness-matched patients who survived were selected randomly as a comparison group. Data on time and causes of death, fluid resuscitation, and management of inhalation injury, associated injuries and wound were collected. Half of the deaths occurred during the first week after burn. The commonest cause of death was sepsis (27 patients), followed by MODS (11 patients), then hypovolaemic shock (4 patients) and pulmonary infection (2 patients). Thirty-six dead patients and 10 surviving patients had received insufficient fluid resuscitation and developed severe shock. Prophylactic tracheotomy was undertaken in 15 patients, of whom 6 died. Thirty-two patients had undergone emergency tracheotomies, of which 29 died. All associated injuries had been well-managed and no death was related to associated injuries or their complications directly. In the group of patients who died, 20 had undergone early excision (within 1 week of injury) and grafting. The number of patients in the survivor group who underwent early excision and grafting was 31. These results indicate that the sepsis and MODS are the two commonest causes of death for the patients who sustained burns by gunpowder explosions in fireworks factory. The optimal managements of this type of burn are as follows: (1) sufficient fluid resuscitation and invasive monitoring if necessary; (2) prophylactic tracheotomy and mechanical ventilation for the patients whose upper-airway edema is present or airway patency is threatened; (3) early excision and grafting of lager-deep wounds and covering with allograft with microautograft (1:10); (4) life-threatening associated injuries must be treated immediately after admitting.

Burns due to gunpowder explosions in fireworks factory: a 13-year retrospective study.

The aim of this study was to evaluate the epidemiology of burns due to gunpowder explosions in fireworks factories. Three hundred and fifty-one patients having burns caused by gunpowder explosions in a fireworks factory were admitted to our center from 1 January 1987 to 31 December 1999 and the clinical notes of 339 patients were available for review. Data on age, sex, size, depth and sites of burn, incidence by month, inhalation injury, associated injuries, number of operations, length of hospital stay, morbidity, mortality, and causes of explosions were recorded. The majority of the patients were male, with a mean age of 36.7 years. The mean total burn surface area was 40.9%, mostly deep burns. The commonest areas of the body to be injured were the head and neck. One hundred and eighty-five patients (55%) were injured in December, November, and January. Sixty-five patients (19%) had an inhalation injury, 35 having tracheotomies and mechanical ventilation. Thirty-five patients (10%) had associated injuries, the commonest being the fracture of limbs (25 patients). Two hundred and thirty-two patients (68%) required operations while the number of operations including debridement and grafting, or tracheotomy, per patient were 2.7. The mean time in hospital of the survivors was 32 days with a range of 1-94 days. Acute respiratory distress syndrome (ARDS) and sepsis were the commonest complications during the early post-burn period (7 days or less) and the later period (>7 days), respectively. Forty-four patients died in this series giving a mortality rate of 13%. The commonest cause of death was sepsis (27 patients), followed by multiple organ dysfunction syndrome (MODS) (11 patients). Most accidents (71%) were caused by too much gunpowder put in at one time and accidents resulting from carelessness while making fireworks. Prevention measures are also discussed.