Regulation of pH on inflation and deflation of biosynthetic gas vesicles used as ultrasound molecular imaging probes / 生物工程学报

Gas vesicles (GVs) are gas-filled protein nanostructures that can regulate the buoyancy of microorganisms such as cyanobacteria and archaea. Recent studies have shown that GVs have the potential to be used as ultrasound molecular imaging probes in disease diagnosis and treatment. However, the mechanism of the inflation and deflation of GVs remains unclear, which hampers the preservation of GVs and gas replacement. In the present study, the environmental pH value was found to be an important factor in regulating the inflation and deflation of GVs. It can not only regulate the inflation and deflation of GVs in vivo to make Microcystis sp. cells present distinct levitation state, but also regulate the inflation and deflation of purified GVs in vitro, and the regulation process is reversible. Our results may provide a technical support for the large-scale production and preservation of biosynthetic ultrasound molecular imaging probes, especially for gas replacement to meet different diagnostic and therapeutic needs, and would facilitate the application of biosynthetic ultrasound molecular imaging probes.

A new method for isolating gas vesicles from Microcystis for ultrasound contrast / 生物工程学报

Gas vesicles are a unique class of gas-filled protein nanostructures which are commonly found in cyanobacteria and Halobacterium. The gas vesicles may scatter sound waves and generate harmonic signals, which enabled them to have the potential to become a novel ultrasound contrast agent. However, the current hypertonic cracking method for isolating gas vesicles contains tedious operational procedures and is of low yield, thus not suitable for large-scale application. To overcome these technical challenges, we developed a rapid and efficient method for isolating gas vesicles from Microcystis. The new H2O2-based method increased the yield by three times and shortened the operation time from 24 hours to 7 hours. The H2O2 method is not only suitable for isolation of gas vesicles from laboratory-cultured Microcystis, but also suitable for colonial Microcystis covered with gelatinous sheath. The gas vesicles isolated by H2O2 method showed good performance in ultrasound contrast imaging. In conclusion, this new method shows great potential for large-scale application due to its high efficiency and wide adaptability, and provides technical support for developing gas vesicles into a biosynthetic ultrasonic contrast agent.

Discovery of Eucalyptin C, derived from the fruits of Eucalyptus globulus Labill., as a novel selective PI3Kγ inhibitor for immunosuppressive treatment / 中国天然药物

The fruits of Eucalyptus globulus Labill. are known to have a plenty of medicinal properties, such as anti-tumor, anti-inflammatory, and immunosuppressive activity. Our previous study found that the phloroglucinol-sesquiterpene adducts in the fruits of E. globulus were immunosuppressive active constituents, especially Eucalyptin C (EuC). Phosphoinositide 3-kinases-γ (PI3Kγ) plays a pivotal role in T cell mediated excessive immune responses. In this study, EuC was first discovered to be a novel selective PI3Kγ inhibitor with an IC

m-Nisodipine inhibited 5-HT-induced proliferation of rat PASMCs through Rho/ROCK signal pathway / 药学学报

This paper is to report the exploration of the activation of Rho/ROCK signal pathway in 5-HT-induced proliferation of rat pulmonary artery smooth muscle cells (PASMCs) and the inhibitory effect of m-Nis on this pathway. PASMCs were cultured with the explant technique. MTT assay was used to explore the proliferation of PASMCs after 5-HT treated for different time and the intervening effect of m-Nis. RT-PCR and Western blot were used respectively to explore the mRNA expression of RhoA, ROCK1 and the protein expression of p-MYPT1 in 5-HT-treated PASMCs and intervening effect of m-Nis. The results of MTT assay suggested that 5-HT (1 µmol · L(-1)) treatment for 12-72 h significantly induced the proliferation of rat PASMCs (P<0.05 or P < 0.01), which were inhibited by m-Nis (1 x 10(-5), 1 x 10(-6), l x 10(-7), 1 x10(-8) mol · L(-1)) in dose-dependent manners (P < 0.05 or P < 0.01). Similarly, the mRNA expression of RhoA, ROCK1 and the protein expression of p-MYPT1 were also inhibited by m-Nis in different degrees (P < 0.05 or P < 0.01). Thus, the results of this study suggested that Rho/ROCK pathway played an important role in 5-HT-induced proliferation of rat PASMCs, m-Nis inhibited 5-HT-induced proliferation obviously, which may be related to the blockage of Rho/ROCK signal pathway.

An Effect Evaluation on the Intervention Mode of AIDS High -risk Behaviors / 预防医学

Objective To explore and assess the intervention mode consist of governments,professional organizations and volunteers for AIDS high -risk behaviors.Methods Commercial sex workers,gays,venereal outpatients and other target population were chosen to be under intervention measures by AIDS high -risk behaviors intervention team consist of government,CDC and volunteers.Then awareness rate,use rate of condom and care rate of infectious were calculated. Results A team of 313 volunteers were set up.The cadres,students and owners of public places were trained and it reached 42 000 person training times in 2012.The awareness rate of AIDS -prevention knowledge among commercial sex workers increased from 76.67% to 91.41% and the use of condom increased from 66.67% to 89.74%.The care rate of infections /patients increased from 0 to 100%.Conclusion This model plays an important role in the AIDS prevention and treatment.It is a good working mechanism to build the intervention mode consist of governments,professional organizations and volunteers.

Effect of enteral nutrition on liver function and inflammatory response after abdominal operation in patients complicated with liver dysfunction / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the effect of enteral nutrition(EN) on liver function and inflammatory response after abdominal operation in patients with liver dysfunction.</p><p><b>METHODS</b>A prospective multicenter study was conducted. Patients requiring EN for at least 5 days after abdominal surgery with at least 1 abnormal liver function index were included. After operations, EN suspensions(TPF-FOS) were administered for 5 days after the return of bowel function with targeted content of 125.52 kJ(30 kcal)·kg(-1)·d(-1) maintained for a minimum of 3 days. Levels of serum pre-albumin, C-reaction protein(CRP), and liver function index were measured and the incidence of systemic inflammatory response syndrome(SIRS) was recorded before operation and 6 days after EN. Occurrence of gastrointestinal discomfort was monitored during the treatment.</p><p><b>RESULTS</b>No statistically significant difference was found in pre-albumin between preoperative level and post-EN level[(175.94±71.79) mg/L vs.(192.22±91.26) mg/L, P=0.162]. Patients with abnormal level of γ-glutamyl transpeptidase were less after EN compared to the preoperative period(30 vs. 40, P=0.041), as was total bilirubin (3 vs. 9, P=0.034). No significant differences in other indices of liver function were found. Total bilirubin and direct bilirubin decreased after EN support(P=0.000 and P=0.015, respectively). CRP was notably reduced after EN support [(48.74±65.16) mg/L vs.(25.79±23.63) mg/L, P=0.009] and the incidence of SIRS largely declined after EN support(19.0% vs. 10.3%, P=0.059). The incidence of gastrointestinal discomfort was 22.4% on postoperative day 1 and declined to 19.0% on postoperative day 5.</p><p><b>CONCLUSION</b>For patients with liver dysfunction, enteral nutrition support with TPF-FOS after abdominal operation can reduce inflammatory response, improve liver function, and maintain serum protein level.</p>

To study the evolution of Yersinia pestis from the point of codon and 16S-ribosome / 中国地方病学杂志

Objective To explore the mutation and evolution of Yersiniapestis(Y. pestis) from the point of codon and 16S-ribosome. Methods Codon preference and 16S-ribosome of Y. pestis were analyzed by bioinformatics. Results Similar codon preference was found among 4 PCD1 Y. pestis, of the 3 old Y. pestis the codon preference between PMT1 and PCD1 was similar. There were some differences between PCD1, PCP1 and Yunnan 6 kb plasmid. Through the analysis of 16S-ribosome, the sequences were found similar in 11 strains of Y. pestis,Yersinia pseudotuberculosis was very close to Y. pestis, with only one nucleotide difference, mutated G-T, and corresponding amino acid methionine (M)-isoleucine (I). There were some differences in sequences of 16S-ribosome in Y. pestis, Escherichia coli and Pulex irritans. Conclusions The time for Y. pestis to obtain PCP1 is later than PMT1 does, in other words, the affinity of Y. pestis with PMT1 was closer than PCP1 with 6 kb plasmid;alteration of 16S-ribosomal nucleotide sites may cause changes in function and structure of 16S rRNA. The lower similarity between 16S-ribosomal sequences of Y. pestis and Pulex irritans indicates the time for co-evolution is very short,and the late emergence of Y. pestis.

Discussion on transmission mechanism of wild rodent plague to human in the northwestern area of Yunnan province / 中国地方病学杂志

Objective To explore the relationship between wild rodent plague and human in wild rodent plague foci of the northwestern area in Yunnan to probe the possible transmission mechanism of wild rodent plague to human. Methods Data of component ratio of rodents and fleas was collected in different areas from 1985 - 1995. Activities and habits of residents regarding the way they keep cats and dogs and parasitic fleas and free fleas indoor were investigated, the dog serum was collected for detecting F1 antibody. Results Eothenomys miletus were main rodents in farmland and shrub, accounting for 48.00% (4753/9902) and 54.50% (4282/7857), Apodemus chevrieri were main rodents in garden, being 50.47% (1332/2639). The component ratio of Neopsylla specialis specialis was 13.31%(229/1720), 12.31%(1678/13 739) and 10.87%(957/8802) respectively in garden, farmland and shrub, higher than in indoor. The component ratio of Frantcpsylla spodix was 39.88% (686/1720), the highest in garden. Thirty-two per cent (32/100) of residents kept cats,in which 63% (20/32) with cat fleas, 68% (68/100) of villages kept dogs, in which 76%(52/68) with fleas. Eighteen parasitic fleas were caught from 43 dogs with a flea index of 0.119 and a rate for fleas of 11.63%, 7 pulex were collected from 17 indoor. Forty-three blood serum samples were obtained from dogs, among which 3 were positive blood serum. Conclusions Residents touch affected animals or media in different situations. The possibility of transmission for wild rodent plague to human exists in loci in a chain of wild rodent plague → fleas or predation → homebred animal plague (cats or dogs) →touching or respiratory → human.

Effect of m-nisoldipine on the Ca2+/CaM/CaN signal pathway in 5-HT-induced proliferation of rat PASMCs / 药学学报

This study is to explore the activation of the Ca2+/CaM/CaN signal pathway in 5-HT-induced proliferation of rat pulmonary artery smooth muscle cells (PASMCs) and the inhibitory effect of m-nisoldipine (m-Nis) on this pathway. PASMCs were cultured with the explant technique. The proliferation of PASMCs was evaluated by MTT assay. Confocal microscopy was used to measure the change of [Ca2+]i. The mRNA expression of CaM and CaN was evaluated by RT-PCR and the activity of CaN was measured according to the instruction of kits. The results of MTT assay suggested that 5-HT (1 micromol x L(-1)) significantly induced the proliferation of rat PASMCs (P < 0.01), which was inhibited obviously by m-Nis (P < 0.05 or P < 0.01). Similarly, m-Nis inhibited 5-HT-induced elevation of [Ca2+]i (P < 0.01). The mRNA expression of CaM, CaN and the activation of CaN were also inhibited by m-Nis at different degrees (P < 0.05 or P < 0.01). Thus, the results of this study suggested that Ca2+/CaM/CaN signal pathway played an important role in 5-HT-induced proliferation of rat PASMCs, the inhibition of m-Nis on proliferation of rat PASMCs may be related to the blockage of Ca2+/CaM/CaN signal pathway by inhibiting the elevation of [Ca2+]i.

Effect of bowel preparation with probiotics on intestinal barrier after surgery for colorectal cancer / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To study the effect of bowel preparation with probiotics on intestinal barrier function after surgery for colorectal cancer.</p><p><b>METHODS</b>A total of 60 patients undergone colonic surgery were randomly divided into two groups:the trial group and the control group. One-day bowel preparation with probiotics was administered in trial group, while 3-day conventional bowel preparation in control group. Quality of the preparation was estimated during operation and the structure of intestinal epithelium in the colon was observed by microscope. Levels of transmembrane binding protein(occludin) and IgA in the colon were detected by immunohistochemistry method. White blood cell counts, microbial DNA, and C-reactive protein were measured before surgery and 1, 7 days after surgery. Postoperative systemic inflammation response syndrome(SIRS) and infection were evaluated.</p><p><b>RESULTS</b>Good and excellent bowel preparation were achieved in 88% in the trial group and 92% in the control group(P=0.072). The expression levels of occludin and IgA of colon were significantly higher in the trial group[(19.32 + or - 2.40)% and (7.60 + or - 1.48)%, respectively] compared with those of the control group [(16.21 + or - 2.54)% and (5.29 + or - 1.57)%,respectively]. The number of microbial DNA PCR-positive patients in the trial group was significantly less than that in the control group after operation. There were no significant differences in the rates of SIRS or complications between the two groups.</p><p><b>CONCLUSION</b>One-day bowel preparation with probiotics can maintain the intestinal barrier function after surgery of colorectal cancer,which is suitable for elective colorectal surgery.</p>

Study on specific metabonomic profiling of serum from colorectal cancer patients by gas chromatography-mass spectrometry / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To study the specific metabonomic profiling of serum from colorectal cancer patients to find out the low molecule metabolites associated intimately with colorectal cancer,and to establish specific metabolic model for the diagnosis of colorectal cancer.</p><p><b>METHODS</b>The metabonomic profiles of the serum samples from colorectal cancer(CRC) patients(n =31) and healthy adults(n =8) were investigated by gas chromatography-mass spectrometry (GC-MS) technique combined with a commercial mass spectral library for the peak clustering based on metabolites.</p><p><b>RESULTS</b>Thirty-four endogenous metabolites including some amino acids, carbohydrates, fatty acids and other intermediate metabolites were identified. By t test statistics with P<0.05, P<0.01 respectively, L-valine, L-threonine, 1-deoxyglucose, glycine and ribitol levels were decreased significantly, but 3-hydroxybutyric acid level was increased significantly in the CRC patient group as compared with healthy adult group. PLS-DA based on these metabolites discriminated two groups for each other. Hierarchical clustering based on above 6 significant differential metabolites revealed that the prediction accuracy of colorectal cancer group was 93.5%.</p><p><b>CONCLUSION</b>GC-MS technique is an alternative tool for the metabonomic study and would be certainly beneficial to the pathological research, early diagnosis and therapy evaluation of CRC.</p>

Proteomic research of biomarker of colorectal cancer metastasis / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To explore the potential markers of colorectal cancer metastasis and the influence of 5-FU on differentially expressed proteins by using proteomic technology, and to elucidate the mechanism of colorectal cancer metastasis.</p><p><b>METHODS</b>Human colorectal carcinoma cell lines of different metastatic potential, Lovo and SW480 were conventionally cultured, and the protein was extracted. 50% inhibitory concentration (IC(50)) of 5-FU to these two cell lines was measured by MTT assay. Proteins of these two cell lines after intervention by 5-FU at IC(50) were extracted, then 2-dimensional gel electrophoresis was conducted for the proteins. The differential protein spots were examined by mass spectrometry and analyzed by bioinformatics. Difference of expressed proteins in two cell lines before and after the intervention of 5-FU was validated by Western blot and immunofluorescence.</p><p><b>RESULTS</b>Eleven differentially expressed proteins were identified by 2-dimensional gel electrophoresis and mass spectrometry. The hnRNP K protein and PDI were selected to be examined by Western blot and immunofluorescence. Results revealed that the expression of hnRNP K in Lovo was higher than that in SW480, while the expression of PDI was lower in Lovo. After intervention by 5-FU at IC(50), the expression of hnRNP K in Lovo decreased more as compared to SW480, while the expression of PDI in SW480 increased more as compared to Lovo.</p><p><b>CONCLUSION</b>There are significant differences in expression of hnRNP K and PDI proteins between Lovo and SW480 cell lines, and the proteins alter regularly after 5-FU intervention.</p>

Influences of enteral nutrition combined with probiotics on the gut microecology and barrier function of the rats with abdominal infection / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the influences of enteral nutrition (EN), parenteral nutrition (PN) and probiotics supplement on the intestinal microecology, and barrier function of the rats with abdominal infection.</p><p><b>METHODS</b>Twenty-one Sprague-Dawley (SD) rats with abdominal infection were randomly divided into three groups, and received PN (PN group, n=7), PN+ EN (PN+ EN group, n=7) or PN+ EN+ probiotics (probiotics group, n=7) respectively with isonitrogen and isocaloric nutrition. The rats were sacrificed after six days. The feces in cecum were cultured for anaerobic bacterial growth and DNA fingerprint spectrum was analyzed by randomly amplified polymorphic DNA technique. The transmembrane binding protein (occludin) and IgA levels in colon and terminal ileum were detected by immunohistochemistry method. The bacterial translocation rate and endotoxin level were also measured.</p><p><b>RESULTS</b>The germ numbers of different species were both higher in PN+ EN and probiotic group than those in PN group. The bands of DNA fingerprint spectrum were significantly decreased in PN group, but the bands in both PN+ EN group and probiotic group were similar to that in the normal rats. The expression levels of occludin and IgA in the intestine and colorectum were higher in both PN+ EN group and probiotic group compared with those of PN group (P< 0.05, P< 0.01, respectively), the expression level of occludin was higher in probiotic group than that in PN+ EN group (P< 0.05). The overall bacterial translocation rates and endotoxin levels were significantly reduced in both probiotic and PN+ EN group (P< 0.05), but there was no difference between probiotic group and EN group.</p><p><b>CONCLUSION</b>EN combined with probiotics can increase occluding and IgA expressions, improve the intestinal microecology,maintain the gut barrier function, and decrease the incidence of gut bacterial translocation.</p>

Effects of enteral nutrition on uptake of amino acid and enzyme-protein synthesis of pancreatic acinar cell in acute pancreatic dogs / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the effect of intrajejunal nutrition on uptake of amino acid and enzyme-protein synthesis in pancreatic acinar cell and subcellular fractionation and zymogen granules in dogs with acute pancreatitis.</p><p><b>METHODS</b>Fifteen dogs were induced acute pancreatitis by retrograde injection of 5% sodium-taurocholate into the pancreatic duct. Radioactive tracing and electron microscope were used to evaluate the change of amino acid uptake, enzyme-protein synthesis in acinar cell, subcellular fractionation, the quantitative analysis of mean zymogen granule number and mean zymogen granule area after injection L-(3)H-phenylalanine 30, 60, 120 1nd 180 min on the 7(th) day.</p><p><b>RESULTS</b>The radioactivity of L-(3)H phenylalanine uptake by pancreatic acinar cells and incorporations of L-(3)H phenylalanine into newly synthesized enzyme-protein peaked at 60 min. In enteral nutrition (EN) group it was higher that that in parenteral nutrition (PN) group (P < 0.05), and then gradually declined. The radioactivity peaked at 60 min in zymogen granule, lysosomal-mitochondria and microsomal subcellular fractionation. The latter two decreased, bat there was no significant difference (P > 0.05). The change of the mean number and mean area of zymogen granules were not significant different between the EN group and PN group (P > 0.05).</p><p><b>CONCLUSION</b>EN or PN do not stimulate pancreatic acinar uptake amino acid and enzyme-protein synthesis in acinar cell and subcellular fractionation.</p>