Soil incubation studies with Cry1Ac protein indicate no adverse effect of Bt crops on soil microbial communities.

Bt crops that are transgenic crops engineered to produce Bt toxins which occur naturally with Bacillus thuringiensis (Bt) have been widely planted and its environmental risk assessment has been heavily debated. The effects of Bt crops on soil microbial communities are possible through changing the quantity and quality of C inputs and potential toxic activity of Bt protein on soil organisms. To date, the direct effects of Bt protein on soil microorganisms is unclear. Here we added Cry1Ac, one of the most commonly used Bt protein in Bt crops, to the soil and monitored changes in soil bacterial, fungal and archaeal diversities and community structures using ribosomal DNA-fingerprinting method, as well as their population sizes by real-time PCR over a 100-day period. Despite the fact that variations were observed in the indices of evenness, diversity and population sizes of bacteria, fungi and archaea with different Cry1Ac addition rates up to 100ngg-1 soil, the indices of soil microbial diversities and evennesses did not significantly shift with Cry1Ac protein addition, nor did population sizes change over time. The diversities of the dominant bacteria, fungi and archaea were not significantly changed, given Cry1Ac protein addition rates over a period of 100 days. These results suggested that Bt protein derived by cultivations of transgenic Bt crops is unlikely to cause transient or even persisting significant changes in soil microorganisms in field.

Effects of acidification pretreatment for respiratory acidosis on the expression of matrix metalloproteinase-9 in rat lung tissues following ischemia/reperfusion / 中南大学学报(医学版)

To establish rat model of lung ischemia/reperfusion (IR) in vivo, and to explore the effects of acidification pretreatment for respiratory acidosis on the expression of matrix metalloproteinase-9 (MMP-9) and the possible mechanisms.
 Methods: A total of 36 male Sprague-Dawley rats were divided into a sham group (S group), a IR group, and an experiment group (RA group) (n=12 in each group). The rat left lung hilum in the S group was dissociated, followed by perfusion without ischemia. After the left lung hilum in the IR group was blocked for 45 min, the rats were followed by reperfusion for 180 min. After left lung hilum in the RA group was dissociated, the respiratory parameters were adjusted so that pressure of end tidal carbon dioxide (PETCO2) reached 56-65 mmHg (1 mmHg=0.133 kPa) for 5 min, then the rats was subjected to IR. Lung tissue wet/dry (W/D) and lung permeability index (LPI) were calculated, while the lung histopathology was observed and the MMP-9 protein expression were measured.
 Results: Compared with the control group, the W/D and LPI in the IR group and the RA group increased after reperfusion (both P<0.05), and the levels of W/D and LPI in the group RA were lower than that in the IR group (P<0.05). LPI and pathology scores were significantly lower in the RA group than those in the IR group (both P<0.01). After IR, the expression of MMP9 in the lung tissues in the IR group and the RA group increased significantly (both P<0.01). The expression of MMP-9 protein in the RA group was significantly lower than that in the IR group (P<0.01).
 Conclusion: After lung IR injury, the expression of MMP-9 protein, vascular permeability and inflammatory exudation is increased. The acidification pretreatment for respiratory acidosis can inhibit the expression of MMP-9 protein and reduce inflammatory exudation after lung IR, showing a protective effect on lung IR injury.

Low-intensity pulsed ultrasound pretreatment inhibits HMGB1 expression and attenuates lung ischemia-reperfusion injury in rats the cholinergic anti-inflammatory pathway / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the effects of low-intensity pulsed ultrasound (LIPUS) pretreatment on pulmonary expression of high mobility group box-1 (HMGB1) in a rat model of lung ischemia-reperfusion (IR).</p><p><b>METHODS</b>Thirty-two male SpragueDawley rats weighing 250-300 g were randomly divided (=8) into sham-operated group, lung IR group, LIPUS pretreatment group and pretreatment with α7-nicotinic cholinergic receptor (α7nAChR) antagonist group. In the sham-operated group, the left pulmonary hilum was dissociated without occlusion; in the other 3 groups, the left pulmonary hilum was occluded for 45 min followed by reperfusion for 180 min; LIPUS pretreatment for 30 min and intraperitoneal injection of methyllycaconitine (2 mg/kg), an α7nAChR antagonist, were administered before the operation. The wet/dry weight ratio (W/D) and pulmonary permeability index (LPI) of the lung tissue were measured, and the lung histopathology was observed and scored. The contents of interleukin-1 (IL-1) and IL-6 in the lung tissues were measured using ELISA, and the pulmonary expression of HMGB1 protein was detected using immunofluorescence assay and Western blotting.</p><p><b>RESULTS</b>Compared with those in the sham-operated group, the W/D of the lung tissue, LPI, pathological scores, IL-1 and IL-6 contents in the lung tissue, and pulmonary HMGB1 expression all significantly increased in the other 3 groups ( < 0.05). LIPUS preconditioning significantly lowered the W/D values, LPI, pathological score, IL-1 and IL-6 contents and HMGB1 expression in the lung tissues following lung IR, and these effects were significantly inhibited by administration of methyllycaconitine.</p><p><b>CONCLUSIONS</b>LIPUS preconditioning can reduce lung IR injury possibly by activating α7nAChR-dependent cholinergic anti-inflammatory pathway to reduce lung tissue HMGB1 expression.</p>

Effects of long-term cultivation of transgenic Bt rice (Kefeng-6) on soil microbial functioning and C cycling.

Understanding how soil ecosystem responds to transgenic Bacillus thuringiensis (Bt) rice is necessary for environmental risk assessment. While the influences of short-term cultivation of Bt rice on soil properties have been reported previously, little is known about the long-term effects of Bt rice on soil ecosystems. In this study, soil samples were taken from a long-term rice cultivation site in Fujian Province, China, where transgenic Bt rice (Kefeng-6) and its non-Bt parent breed (Minghui-86) had been continuously cultivated for 8 years. Soil Bt protein concentration and a total of 16 variables were analyzed to assess potential risks of soil health under Bt rice cultivation. The results revealed that soil Bt protein is unlikely to accumulate after Bt rice cultivated in the field, and no consistently significant changes were observed in soil enzymatic activities (catalase, dehydrogenase, acid phosphatase, and urease), microbial biomass (microbial carbon and nitrogen), total organic carbon, decomposition (soil respiration, Q 10, and qCO2), soil nitrogen and phosphorus contents. Due to a local tradition that aboveground biomass was removed after harvest, the increased net primary productivity by Bt rice cultivation did not significantly change soil C cycling. Results of this study suggested that on the aspects of soil microbial functioning and C cycling, long-term cultivation of Bt rice is unlikely to result in significant effects on soil health.

Disposable Whole Bed Sheet and Its Reel Device: Design and Clinical Application / 中华医院感染学杂志

OBJECTIVE To overcome shortcomings in use of bed sheet,and to improve it for examining bed.METHODS Based on the working principle of the reel toilet paper and industrial drive belt,a reel device for(disposable) whole bed sheet was designed,and used on the bed examining more than 300 times.(RESULTS) The new designed reel aevice with disposable whole bed sheet was operated easy and safely,with decreased cost and(contamination) in use.It could alleviate infection opportunity in favor of control againt hospital infection and(environmental) protection.(CONCLUSIONS) The device can mount on any size of examining bed and widely accept for use.

Unreported Hospital Infection: Analysis and Countermeasures / 中华医院感染学杂志

OBJECTIVE To ascertain the causes of unreported hospital infection in our hospital and apply countermeasures. METHODS To adopt investigation way to review and analyze 34 694 hospital files in our hospital from Aug 2002 to Jul 2004. RESULTS From them 1164 cases had experienced hospital infection,264 were unreported,the monthly unreported rate decreased from 52.50% to 0;the yearly unreported rate decreased from 36.17% to 10.67%. CONCLUSIONS The unreported reason is because the relevant staff lack infection knowledge,the control and supporting system isn′t so efficient.So the key to reduce the missing report rate is to enhance the awareness of the hospital infection control among the staff in hospital,to strengthen communication and cooperation,and to implement the administrative regulation.