水稻幼苗抗感性的动力学分析

通过3个品种的胁变过程的分析,表明:1.用向心力和切向力或离心力和切向力进行胁变分析是可行的.2.通过分析认为存在频率、阻尼和相位三种抗性因素.3.通过进一步分析认为阻尼与耐性相关,相位与避性相关,因此可以认为频率、耐性和避性是抗性的三个因素.4.继而认为存在避耐性抗性,避频抗性和耐频抗性三种抗性形式.5.在Levitt抗性理论中只有避耐一种抗性形式。本文突破了这种模式.

日本和西欧大麦品种对我国大麦黄花叶病的抗感性反应

据39个日本大麦品种和48个西欧大麦品种对中国大麦黄花叶病毒(Ba YMV)分离物的抗病性反应得出,抗日本BaYMV的大麦品种,多数也抗中国的BaYMV,少数为感。感日本BaYMV的大麦品种,多数也感中国的BaYMV,仅少数为抗病,说明中、日两国BaYMV分离物的致病性差异较小。抗西欧BaYMV的大麦品种,对中国的BaYMV,多数品种为感,少数品种为抗。感西欧BaYMV的大麦品种,多数也感中国的BaYMV,少数品种抗。说明中国和西欧两地区BaYMV分离物的致病性差异较大。中国BaYMV分离物的致病力和日本的相似,都比西欧的BaYMV分离物要强。作者还讨论了造成BaYMV致病性差异的可能原因。

不同抗性小鼠ECTV感染前后重要模式识别受体的组织表达差异分析

探讨抗性/易感小鼠DNA识别受体的组织表达差异与抗病性的关系。方法不同抗性品系小鼠感染ECTV后,采用实时荧光定量PCR(qRT-PCR)技术分析其组织的重要DNA识别受体差异表达谱。结果TLR9、DAI、cGAS、RNA pol III和RIG-I这5个与DNA识别相关的受体在不同抗性小鼠组织中均呈广泛性表达,但鼠痘抗性小鼠C57BL/6品系的表达明显整体高于BALB/c小鼠;在ECTV感染后易感小鼠BALB/c品系的这些基因表达明显上调,而C57BL/6小鼠变化不大甚至下调。结论这种差异表达特征表明这些受体分子可能与小鼠的天然抗病力密切相关。

miR-200b-3p和miR-200b-5p在马立克氏病抗性与易感SPF鸡法氏囊组织的差异表达分析

目的在前期高通量测序分析的基础上,进一步利用荧光定量PCR验证miR-200b-3p和miR-200b-5p在马立克氏病(MD)抗性(B21单倍型)与易感(B19单倍型)鸡法氏囊组织的差异表达情况。方法通过经优化后确定的最佳实时荧光定量PCR反应体系和扩增条件,进行荧光定量PCR分析。结果 miR-200b-3p和miR-200b-5p荧光定量PCR结果与高通量测序结果上下调情况基本一致,但差异表达显著性分析结果却不完全相同。结论尽管差异表达显著性分析结果不完全一致,但两种方法的结果均提示来源于同一前体的miR-200b-3p和miR-200b-5p可能与MD抗性/易感性相关。

In vitro Antimicrobial Activity of Golden Buckwheat Extract and Therapeutic Effect of its Preparation on Chicken Mycoplasma Infection

[Objective] This study aimed to identify the in vitro antibacterial activity of golden buckwheat extract and investigate the therapeutic effect of its preparation on mycoplasma infection. [Method] Through measuring the minimum inhibitory concentra-tion, the in vitro antibacterial activity of golden buckwheat water extract was deter-mined; meanwhile, the therapeutic effect of golden buckwheat oral solution on my-coplasma infection was determined by artificial y infecting chickens with Mycoplasma gal isepticum culture. [Results] The golden buckwheat water extract had obvious in-hibitory effects against Pseudomonas aeruginosa and Escherichia coli, and a certain inhibitory effect on Salmonel a and Staphylococcus aureus; administration of golden buckwheat oral solution at the dose of 0.5%-1.0% continuously for 5 d had a good therapeutic effect against mycoplasma infection. [Conclusion] The study provides sci-entific bases for further study on the antibacterial activity of golden buckwheat and its application.

氟对骨形成和矿化的作用受遗传因素的影响

目的本实验以牙釉质对氟具有不同敏感性、近亲交配的3个小鼠品系(A/J:易感品系;SWR/J:中度易感品系;129P3/J:抗性品系)逐级增加氟剂量(0、25、50、100μg/L),证明对这些小鼠皮质骨及松质骨力学性能有不同影响。方法研究采用了微型计算机断层摄影、小连接体分析、静态组织形态测定、反向散射电子(BSE)成像、X射线粉末衍射等方法对3个品系小鼠骨的形成、骨的显微结构、矿化作用和显微硬度值等相关指标分别进行了测定。结果3个品系小鼠在最大氟剂量时其骨形成有显著增加;随F^-剂量增加,小鼠骨矿化程度无显著提高,只有SWR/J品系小鼠在50、100μg/L剂量时其椎体松质骨的矿化不均一程度明显降低;3个品系除129P3/J品系自身晶体较小外,随F^-剂量增加3者晶体的宽度都显著增加;F^-处理对三品系皮质骨和松质骨的显微硬度值无任何影响。结论氟作用对3品系骨微结构无显著影响,类骨质形成的增加和矿化不均一程度的降低都支持F^-离子延迟新骨矿化的理论;晶体宽度随F^-剂量的增加而增加的现象证实了早期的研究结果,并与大多数骨力学性能的降低相关;骨中F^-的增加可能影响了骨基质蛋白的性质,妨碍了骨晶体在微晶体面的生长抑制和有机-无机相界面间的结合;129P3/J抗性品系存在较强的有机-无机相界面,可能会降低微晶体的生长速率,故该品系自身骨晶体最小,受氟作用影响不显著。

Is the Potential Interconnection between Antibiotic Susceptibility and Disinfectant Resistance a Threat to Food Safety?

The prevalence of antibiotic susceptibility and disinfectant resistance in bacterial pathogens causes a serious problem not only to food safety but also to public health, which directly or indirectly leads to treatment and disinfection failures. In this review, multidrug resistance, the mechanism of disinfectant resistance, the methods for detecting disinfectant resistance and the cross-resistance between an- tibiotics and disinfectants are summarized. More efforts should be devoted to explor- ing the professional guidance of using antibiotics and disinfectants, and to develop- ing the comprehensive detection with genetic and molecular methods is highly ex- pected.

Antimicrobial activity of Sapindus mukorossi and Rheum emodi extracts against H pylori: In vitro and in vivo studies

AIM： To evaluate the antibacterial activity of Sapindus mukorossi （S. mukorossl） and Rheum emodi （R. emodl）. METHODS： Powders of S. mukorossi and R. emodi were extracted successively with petroleum ether, benzene, chloroform and ethanol and were concentrated in vacuum. The disk diffusion method was used for in vitro studies and in vivo studies were performed on male Wister rats. Thirty resistant clinical isolates of H pylon, as determined by their antibiotic sensitivity patterns by E-test, along with two Gram ＋ve （S. aureus, B. subtilis） and two Gram -ve （E. coli, P. vugaris） organisms were screened for their susceptibility patterns against these extracts. RESULTS： In our screening, all 30 resistant isolates and the other four organisms （two Gram ＋ve S. aureus, B. subtilis and two Gram -ve, E. coli, P. vugaris） were sensitive to the test compounds. It was found that ethanol and chloroform extracts of S. mukorossi and ethanol and benzene extracts of R. emodi inhibited Hpylori at very low concentrations, In the in vitro study, the isolates showed a considerable zone of inhibition at very low concentrations （10 μg/mL） for both the extracts. In the in vivo study, the H pylori infection was cleared with minimal doses of extracts of S. mukorossi （2.5 mg/mL） and R. emodi （3.0 mg/mL） given orally for seven days. CONCLUSION： We can conclude from this study that the extracts of S. mukorossi and R. emodi inhibited the growth of pylori in vitro and, in in vivo studies, the H pylori infection cleared within seven days at very low concentrations. We also found that H pylori did not acquire resistance against these herbal extracts even after 10 consecutive passages.

免疫性血小板减少症发病机制的研究进展

免疫性血小板减少症(ITP)是临床上常见的一种获得性自身免疫紊乱性疾病,以血小板计数减低、皮肤黏膜及内脏出血为主要临床表现,是常见的出血性疾病之一。ITP发病机制较复杂,涉及体液免疫紊乱、细胞免疫异常、血小板自身抗体增加、巨核细胞功能异常、细菌病毒感染、氧化抗氧化状态失衡、遗传易感性、妊娠反应、药物不良影响等多个方面。

Aspirin increases susceptibility of Helicobacter pylori to metronidazole by augmenting endocellular concentrations of antimicrobials

AIM： To investigate the increasing the susceptibility pylon） to metronidazole. mechanisms of aspirin of Helicobacter pylori （H METHODS： Hpylori reference strain 26695 and two metronidazole-resistant isolates of H pylori were included in this study. Strains were incubated in Brucella broth with or without aspirin （1 mmol/L）. The rdxA gene of Hpylori was amplified by PCR and sequenced. The permeability of Hpylori to antimicrobials was determined by analyzing the endocellular radioactivity of the cells after incubated with [7-^3H]-tetracycline. The outer membrane proteins （OMPs） of Hpylori 26695 were depurated and analyzed by SDS-PAGE. The expression of 5 porins （hopA, hopB, hopC, hopD and hopE） and the putative RND efflux system （hefABC） of H pylori were analyzed using real-time quantitative PCR. RESULTS： The mutations in rdxA gene did not change in metronidazole resistant isolates treated with aspirin. The radioactivity of H pylori increased when treated with aspirin, indicating that aspirin improved the permeability of the outer membrane of H pylori. However, the expression of two OMP bands between 55 kDa and 72 kDa altered in the presence of aspirin.The expression of the mRNA of hopA, hopB, hopC, hopD, hopE and herA, hefB, hefC of H pylori did not change when treated with aspirin. CONCLUSION： Although aspirin increases the susceptibility of H pylori to metronidazole, it has no effect on the mutations of rdxA gene of Hpylori. Aspirin increases endocellular concentrations of antimicrobials probably by altering the OMP expression.

Isolation,characterization and extraction of mer gene of Hg^(2+) resisting strain D_2

Mercury-resistant strain D2 was isolated from mercury-contaminated soil and investigations on its 16S rDNA sequence,growth,minimal inhibitory concentrations(MICs) of metals,antibiotic susceptibility and mer gene were conducted.The strain D2 can grow in the medium containing 60 mg/L mercury ion.It presents more than 99% identity of 16S rRNA gene with Pseudomonas aeruginosa,and exhibits high MIC values for heavy metals and a large spectrum antibiotics resistance.The mer RT gene sequence was amplified from chromosome.Strain D2 is identified as Pseudomonas aeruginosa and the resistance to mercuric ion is related to chromosome.

Drug sensitivity and drug resistance profiles of human intrahepatic cholangiocarcinoma cell lines

AIM: To study the effect of a number of chemotherapeutic drugs on five human intrahepatic cholangiocarcinoma (CCA) cell lines. The expressions of genes that have been proposed to influence the resistance of chemotherapeutic drugs including thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), glutathione-S-transferase PI (GSTP1), multidrug resistance protein (MDR1) and multidrug resistance-associated proteins (MRPs) were also determined. METHODS: Five human CCA cell lines (KKU-100, KKU-M055, KKU-M156, KKU-M214 and KKU-OCA17) were treated with various chemotherapeutic drugs and growth inhibition was determined by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. Semi-quantitative levels of gene expression were determined by a reverse transcriptase polymerase chain reaction (RT-PCR). Results of IC_(50) values and the ratios of gene expression were analyzed by linear regression to predict their relationship. RESULTS: Among five CCA cell lines, KKU-M055 was the most sensitive cell line towards all chemotherapeutic drugs investigated, particularly taxane derivatives with IC_(50) values of 0.02-3 nmol/L, whereas KKU-100 was apparently the least sensitive cell line. When compared to other chemotherapeutic agents, doxorubicin and pirarubicin showed the lowest IC_(50) values (＜5 μmol/L) in all five CCA cell lines. Results from RT-PCR showed that TS, MRP1, MRP3 and GSTP1 were highly expressed in these five CCA cell lines while DPD and MRP2 were only moderately expressed. It should be noted that MDR1 expression was detected only in KKU-OCA17 cell lines. A strong correlation was only found between the level of MRP3 expression and the IC_(50) values of etoposide, doxorubicin and pirarubicin (r=0.86-0.98, P＜0.05). CONCLUSION: Sensitivity to chemotherapeutic agents is not associated with the histological type of CCA. Choosing of the appropriate chemotherapeutic regimen for the treatment of CCA requires knowledge of drug sensitivity. MRP3 was correlated with resistance of CCA cell lines to etoposide, doxorubicin and pirarubicin, whereas other chemotherapeutic drugs showed no association. The role of this multidrug resistance-associated protein, MRP3, in chemotherapeutic resistance in CCA patients needs to be further investigated.

Research Progress in Phage

With excessive utilization of antibiotics in recent years,bacterial drug resistance problem is serious increasingly,and it is more and more difficult to develop anti-infective drug,while it does not have these problems to use phage controlling disease.Phage is a kind of prokaryotic virus,widely exists in the nature and includes bacteriophage,cyanophage and actinophage.Due to its potential of replacing antibiotics to treat disease,phage receives more and more attention.In this paper,based on development status of phage research at home and abroad,discovery process,naming method and classification basis of phage are introduced comprehensively,and advantages and limitations of phage applying in prevention and control of bacterial diseases are analyzed.We introduce application status of phage in human medicine,prevention and control of diseases for terrestrial animals and aquaculture,and the effects of phage in sewage treatment,prevention and control of microbial contamination of food and detection technology,and point out the shortages of phage in the above application.Meanwhile,we also discuss application prospects of phage in disease prevention and control,environmental protection and food safety.

Relationship of human leukocyte antigen class II genes with the susceptibility to hepatitis B virus infection and the response to interferon in HBV-infected patients

AIM： To study the relationship of human leukocyte antigen （HLA）-DRB1 and -DQB1 alleles with the genetic susceptibility to HBV infection and the response to interferon （IFN） in HBV-infected patients. METHODS： Low-resolution DNA typing kit was used to determine HLA-DR-1 and -DQB1 genes in 72 patients with chronic hepatitis B （CHB） and HLA-DRB1 in 200 healthy people ready to donate their bone marrow in Shanghai. Among CHB patients, 35 were treated with IFNα-1b for 24 wk. RESULTS： The frequencies of HLA-DRBI＊06, DRBI＊08 and DRB1＊16 alleles in 72 patients were higher than in 200 healthy people （2.08% vs0%, OR = 3.837, P= 0.018; 11.11% vs5.50%, OR = 2.148, P= 0.034; and 6.94% vs 3.00%, OR = 0.625, P = 0.049, respectively）; whereas that of DRBI＊07 allele was lower （2.78% vs 7.75%, OR = 0.340, P= 0.046）. The frequency of HLA-DRBI＊ 14 allele was higher in 11 responders to IFN compared with 24 non-responders （18.18% vs2.08%, OR = 10.444, P = 0.031）, whereas that of DQBI＊07 allele was inverse （9.09% vs37.50%, OR = 0.167, P= 0.021）. CONCLUSION： The polymorphism of HLA class II may influence the susceptibility to HBV infection and the response to IFN in studied CHB patients. Compared with other HLA-DRB1 alleles, HLA-DRBI＊06, DRBI＊08, and DRB1＊16 may be associated with chronicity of HBV infection, HLA-DRBI＊07 with protection against HBV infection, and HLA-DRB1＊14 allele may be associated with a high rate of the response of CHB patients to IFN treatment. Compared with other HLA-DQB1 alleles, HLA-DQBI＊07 may be associated with low response rate to IFN. 2005 The WJG Press and Elsevier Inc. All rights reserved

Antibacterial and antifungal activities of different parts of Tribulus terrestris L. growing in Iraq

Antimicrobial activity of organic and aqueous extracts from fruits, leaves and roots of Tribulus terrestris L., an Iraqi medicinal plant used as urinary anti-infective in folk medicine, was examined against I l species of pathogenic and non-pathogenic microorganisms： Staphylococcus aureus, Bacillus subtilis, Bacillus cereus, Corynebacterium diphtheriae, Escherichia coli, Proteus vulgaris, Serratia marcescens, Salmonella typhimurium, Klebsiella pneumoniae, Pseudomonas aeruginosa and Candida albicans using microdilution method in 96 multiwell microtiter plates. All the extracts from the different parts of the plant showed antimicrobial activity against most tested microorganisms. The most active extract against both Gram-negative and Gram-positive bacteria was ethanol extract from the fruits with a minimal inhibitory concentration （MIC） value of 0.15 mg/ml against B. subtilis, B. cereus, P. vulgaris and C. diphtheriae. In addition, the same extract from the same plant part demonstrated the strongest antifungal activity against C. albicans with an MIC value of 0.15 mg/ml.

Antiviral Activity of the Effective Monomers from Folium Isatidis Against Influenza Virus in Vivo

In order to evaluate the anti-influenza virus activity of the effective monomer from Folium Isatidis (FI) in vivo,we established mice model with viral pneumonia and divided them into 3 different dose groups,then observed their lung indexes,pulmonary pathological changes,pulmonary virus hemagglitination titers,living time and death rates.The results showed that the monomer could reduce the pulmonary index from 2.64 to 1.93,1.63 and 1.40 (P<0.01) and decrease the hemagglitination titer from 1.15 to 0.84,0.70 and 0.59 (P<0.01).In addition,different groups of FI could significantly lessen the mortality rate from 100% to 30%,25% and 15%,and prolong the living time from 5.1d to 6.5d,8.4d and 8.9d respectively(P<0.01).The high dose (75 mg/kg/d) has the similar effect with 100 mg/kg/d dose of virazole(P>0.05),and more effective than 200 mg/kg/d dose of antiviral liquor (P<0.05).

Microbial profile and antibiotic sensitivity pattern in bile cultures from endoscopic retrograde cholangiography patients

AIM： To identify the frequency of bacterial growth, the most commonly grown bacteria and their antibiotic susceptibility, and risk factors for bacterial colonization in bile collected from patients with different biliary dis- eases. METHODS： This prospective study was conducted be- tween April 2010 and August 2011. Patients with vari- ous biliary disorders were included. Bile was aspirated by placing a single-use, 5F, standard sphincterotome catheter into the bile duct before the injection of con- trast agent during endoscopic retrograde cholangio- pancreaticography （ERCP）. Bile specimens were trans- ported to the microbiology laboratory in blood culture bottles within an anaerobic transport system. Bacteria were cultured and identified according to the standard protocol used in our clinical microbiology laboratory. The susceptibilities of the organisms recovered were identified using antimicrobial disks, chosen according tothe initial gram stain of the positive cultures RESULTS： Ninety-one patients （27% male, mean age 53.7 4- 17.5 years, range： 17-86 years） were included in the study. The main indication for ERCP was benign biliary disease in 79 patients and malignant disease in 12 patients. The bile culture was positive for bacterial growth in 46 out of 91 （50.5%） patients. The most frequently encountered organisms were Gram-negative bacteria including Escherich/a coli （28.2%）, Pseudo- monas （17.3%） and Stenotrophomonas rnaltophilia （15.2%）. There were no significant differences between patients with malignant and benign disease （58% vs 49%, P = 0.474）, patients with acute cholangitis and without acute cholangitis （52.9% vs 50%, P = 0.827）, patients who were empirically administered antibiotics before intervention and not administered （51.4% vs 60.7%, P = 0.384）, with regard to the bacteriobilia. We observed a large covering spectrum or low resistance to meropenem, amikacin and imipenem. CONCLUSION： We did not find a significant risk fac- tor for bacteriobilia in patients with biliary obstruction. A bile sample for microbiological analysis may become a valuable diagnostic tool as it leads to more accurate selection of antibiotics for the treatment of cholangitis.

Technology of load-sensitivity used in the hydraulic system of an all-hydraulic core rig

The existing hydraulic system always have problems of temperature rise,runningstability and anti-interference of the implementation components,reliability of hydrauliccomponents,maintenance difficulties,and other issues.With high efficiency,energysaving,reliability,easy operating,stable running,anti-interference ability,and other advantages,the load-sensitive hydraulic system is more suitable for coal mine all-hydrauliccore rig.Therefore,for the technical development of the coal mine all-hydraulic core rig,the load-sensitive technology employed by the rig should be of great significance.

Probiotic intervention has strain-specific anti-inflammatory effects in healthy adults

AIM： To evaluate the effects of three potentially anti-inflammatory probiotic bacteria from three different genera on immune variables in setting based on previous in cytokine responses. healthy adults in a clinical vitro characterization of METHODS： A total of 62 volunteers participated in this randomized, double-blind and placebo-controlled parallel group intervention study. The volunteers were randomized to receive a milk-based drink containing either Lactobacillus rhamnosus GG （LGG）, Bifidobacterium animalis ssp. lactis Bb12 （Bb12）, or Propionibacterium freudenreichii ssp. shermanii JS （PJS） or a placebo drink for 3 wk. Venous blood and saliva samples were taken at baseline and on d 1, 7 and 21. Fecal samples were collected at baseline and at the end of intervention. RESULTS： The serum hsCRP expressed as the median AUC0-21 （minus baseline） was 0.018 mg/L in the placebo group, -0.240 mg/L in the LGG group, 0.090 mg/L in the Bb12 group and -0.085 mg/L in the PJS group （P = 0.014）. In vitro production of TNF-α from in vitro cultured peripheral blood mononuclear cells （PBMC） was significantly lower in subjects receiving LGG vs placebo. IL-2 production from PBMC in the Bb12 group was significantly lower compared with the other groups. CONCLUSION： In conclusion, probiotic bacteria have strain-specific anti-inflammatory effects in healthy adults.

Antimicrobial management of intra-abdominal infections:Literature's guidelines

Antimicrobial management of severe intra-abdominal infections (IAIs) involves a delicate balance of optimizing empirical therapy,which has been shown to improve clinical outcomes,while simultaneously reducing unnecessary antimicrobial use.Two sets of guidelines for the management of intra-abdominal infections were recently published.In 2010,the Surgical Infection Society and the Infectious Diseases Society of America (SIS-IDSA) created guidelines for the diagnosis and management of complicated IAIs.The new SIS-IDSA guidelines replace those previously published in 2002 and 2003.The World Society of Emergency Surgery (WSES) guidelines represent additional contributions,made by specialists worldwide,to the debate regarding proper antimicrobial drug methodology.These guidelines represent the conclusions of the consensus conference held in Bologna,Italy,in July 2010 during the first congress of the WSES.