花生黄曲霉侵染抗性持久性及种皮完整性对产毒的影响

花生种子及制品极易受黄曲霉菌侵染。利用不同的抗病种质为材料,对黄曲霉菌侵染抗性的持久性以及种皮完整性对产毒的影响进行了研究。结果表明,在常温条件下,抗黄曲霉侵染的花生种子至少可以安全贮藏7个月,其与新鲜种子受黄曲霉菌侵染后的发病率和发病指数差异不显著。但是,贮藏9个月的花生种子其抗病能力明显降低。完整种皮对黄曲霉菌产毒能力的影响在抗侵染与感病种质之间存在较大差异。对于抗黄曲霉侵染种质,受黄曲霉菌侵染后,具备完整种皮的种子比破损种皮种子的毒素含量低;对于感病种质,受黄曲霉菌侵染后,具备完整种皮的种子比破损种皮种子的毒素含量高。有关成分分析表明,高含油量、高蛋白质含量和高油酸资源对黄曲霉菌侵染和产毒的抗性较差。相关分析表明,不同花生品种对黄曲霉菌的侵染抗性与油酸含量呈显著负相关,与亚油酸含量呈显著正相关;不同花生品种对黄曲霉菌产毒的抗性与含油量呈显著负相关。通过鉴定和筛选,发掘出2份优质抗病资源G845和G8。

抗黄曲霉侵染与产毒的花生品种筛选

花生是我国重要的经济作物和油料作物,易被黄曲霉侵染。黄曲霉产生的黄曲霉毒素具有强毒性和强致癌性,严重威胁花生食品安全和人体健康,不利于花生产业健康发展。为了筛选抗黄曲霉侵染与产毒的花生品种,本研究采用孢子菌悬液侵染法,以37个花生品种的籽仁为试验材料,利用黄曲霉侵染指数和黄曲霉毒素B_(1)(AFB_(1))含量分析比较各品种的抗侵染性。结果显示,37个花生品种籽仁的黄曲霉侵染指数分布范围为11.00%~80.33%,筛选出中抗黄曲霉侵染品种13个,中感黄曲霉侵染品种19个,感黄曲霉侵染品种4个和高感黄曲霉侵染品种1个,未筛选出高抗品种。AFB_(1)检测结果表明,黄曲霉毒素B_(1)含量最低的3个花生品种为花育23号、花育616和花育9121。相关性分析结果表明黄曲霉侵染指数与AFB_(1)含量呈显著正相关。

花生荚壳抗黄曲霉菌侵染的鉴定方法研究及抗性种质发掘

黄曲霉毒素污染是影响花生食用安全性和制约产业发展的重要因素。荚壳是花生抵御黄曲霉菌侵染的第一道防线,为建立花生荚壳抗黄曲霉侵染的鉴定方法,本研究利用强侵染黄曲霉菌AF2202接种花生荚果,通过对不同接种菌浓度和培养时间的比较分析,发现接种浓度为2×10~6孢子/mL、培养7d的组合方案可以有效区分花生荚壳对黄曲霉菌侵染的抗性。利用所建立的鉴定方法对276份遗传变异丰富的花生核心种质材料进行接种鉴定,进一步证明了这一方法鉴定花生荚壳抗性的有效性和实用性,初步发掘出2份具有荚壳抗性的特异花生种质。

大麦赤霉病抗源的发掘与评价

为了发掘新的大麦赤霉病抗源,2005、2006年利用禾谷镰刀菌单花滴注和喷雾接种相结合的方法,研究了287份大麦品种对赤霉病的抗扩展性和抗侵染性。结果表明,大麦赤霉病抗性除了抗初侵染类型外还存在抗扩展类型。比较两年单花滴注接种后21 d的病小穗率,筛选得到9个抗源,分别为盐96157、2000品12、秀9744、Vivar、Phoenix、盐94148、鉴35、盐97001、96AC20-30,占全部供试品种的3.44%。通过比较喷雾接种21 d后病小穗率、病穗率、病情指数、反应级等各项指标,发现9个抗源中存在三种类型:盐96157、2000品12、盐94148和Vivar属于既抗扩展又抗侵染的类型,秀977、鉴35和Phoenix属于抗侵染性较弱而抗扩展性强的类型,盐97001和96AC20-30属于抗侵染性强而抗扩展性较弱的类型。在9个抗源中96AC20-30抗侵染性也最强。

光固化复合树脂色泽稳定性影响因素的研究进展

光固化复合树脂因色泽美观、操作简便和生物相容性良好,目前已广泛应用于口腔临床,随着口腔材料学的飞速发展,光固化复合树脂生产技术不断提高,在单体结构、化学性质、填料含量、尺寸和形状等方面经过多次改进,具备了良好的理化性能,但研究显示,该材料在修复后一段时间会发生不同程度的色泽改变,影响美观,造成修复失败。引起光固化树脂色泽改变的因素包括两方面:一方面是内部因素,即由固有成分填料、基质及基质/填料界面的理化性能改变而导致的内部变色,以及在该过程中吸水膨胀而引起的色素渗透,这种变色通常是不可逆的,需要重新修复;另一方面是外部因素,主要与饮食中的色素、医源性因素、患者的口腔卫生及吸烟等有关,外部因素的作用可形成斑块、污渍和色素沉着,这种色泽改变通常是浅表的,可以通过打磨抛光去除。本文将对光固化复合树脂色泽稳定性的影响因素进行综述。

白裤瑶粘膏画染研究——白裤瑶粘膏画染与传统靛染的区别探究

白瑶(白裤瑶)是我国南方一个具有古老色彩的民族,这里有着历史悠久的文化传统,有着丰富的传统手工艺,粘膏画染则是其中最有代表性的传统手工艺之一。白裤瑶粘膏画染包含了染色和防染色两种形态的传统手工艺。目前,对白裤瑶粘膏画染色工艺进行了较为详细研究的文献并不多。因此,对白裤瑶粘膏画染工艺的的研究分析有其重要的价值。本文是以收集文献资料结合实地考察得到的粘膏画染相关内容进行整理,从传统染色工艺特点、白裤瑶粘膏画染的染色过程和传统染色突破与对比、白裤瑶粘膏画染与传统靛染的区别等方面阐述,进行理论性研究。

Genome Analysis in Wheat Breeding for Disease Resistance

A brief review on the development of wheat germplasm with introduced powdery mildew and scab resistance from Haynaldia villosa Sch. and Leymus racemosus Lam., Roegneria ciliaris (Trin.) Nevski as well as R. kamoji C. Koch respectively was made. In the course of germplasm development, genome analysis by means of chromosome banding, genomic in situ hybridization (GISH) or fluorescence in situ hybridization (FISH), molecular markers, particularly restriction fragment length polymorphism (RFLP) coupled with aneuploid analysis was employed for the purpose of improving breeding efficiency. Potential use of such germplasm in wheat breeding practice, basic studies and some related problems were also discussed.

Variations in Antioxidase Activities and MDA Content in Potato Tubers Infected by Fusarium trichothecioides

[Objective] This study was conducted to determine the physiological and biochemical characteristics of potato tubers infected by Fusarium trichothecioides. [Method] The soluble protein content, SOD activity, POD activity and malondialdehyde （MDA） content of the tubers of two potato varieties Atlantic and Keshan 1 infected by F. trichothecioides were measured 0, 3, 6, 9, 12, 24 and 48 h later. [Result] Com- pared with the control uninfected, the contents of soluble protein and MDA in the tu- bers of both potato varieties infected with F. trichothecioides decreased, while the SOD activity increased, indicating that SOD activity had a certain relationship with the resistance of potato to dry rot. The POD activity in Keshan 1 which is resistant to F. trichothecioides was higher than in Atlantic, which is susceptible to F. trichothe- cioides, indicating that POD activity was closely related with potato＇s resistance to Fusarium dry rot. [Conclusion] The physiological and biochemical characteristics of potato tubers infected by F. trichothecioides will provide some references for the early waming and prevention of Fusariurn dry rot.

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.

Mapping QTLs Associated with Sheath Blight Resistance Using Chromosome Segment Substitution Lines of Rice(Oryza sativa L.)

In this study, a population of 119 chromosome segment substitution lines （CSSLs） derived from backcross between indica 9311 and japonica Nipponbare was employed to map quantitative trait loci （QTL） associated with sheath blight resis-tance in rice with toothpick inoculation method. A total of three sheath blight resis-tance-associated QTLs （qsb8-1, qsb8-2 and qsb8-3） were identified, which were lo-cated on adjacent molecular markers RM3262, RM5485 and RM3496 of chromo-some 8; the genetic interval was 81.7cM-91.7cM, 91.7cM-108.1cM and 108.1cM-119.6cM, respectively. The additive effect of qsb8-2 was negative, indicating that sheath blight resistance of susceptible parent harboring qsb8-2 fragment was en-hanced; additive effects of qsb8-1 and qsb8-3 were positive, indicating that sheath blight resistance of susceptible parent harboring qsb8-1 and qsb8-3 fragments was reduced.

Molecular and Physical Mapping of Powdery Mildew Resistance Genes and QTLs in Wheat: A Review

Wheat powdery mildew （Pro） is a major disease of wheat worldwide. During the past years, numerous studies have been published on molecular mapping of Pm resistance gene（s） in wheat. We summarized the relevant findings of 89 major re- sistance gene mapping studies and 25 quantitative trait loci （QTL） mapping studies. Major Pm resistance genes and QTLs were found on all wheat chromosomes, but the Pm resistance genes/QTLs were not randomly distributed on each chromosome of wheat. The summarized data showed that the A or B genome has more major Pm resistance genes than the D genome and chromosomes 1A, 2A, 2B, 5B, 5D, 6B, 7A and 7B harbor more major Pm resistance genes than the other chromosomes. For adult plant resistance （APR） genes/QTLs, B genome of wheat harbors more APR genes than A and D genomes, and chromo- somes 2A, 4A, 5A, 1B, 2B, 3B, 5B, 6B, 7B, 2D, 5D and 7D harbor more Pm resistance QTLs than the other chromosomes, suggesting that A genome except 1A, 3A and 6A, B genome except 4B, D genome except 1D, 3D, 4D, and 6D play an impor- tant role in wheat combating against powdery mildew. Furthermore, Pm resistance genes are derived from wheat and its rela- tives, which suggested that the resistance sources are diverse and Pm resistance genes are diverse and useful in combating against the powdery mildew isolates. In this review, four APR genes, Pm38/Lr34/Yr18/Sr57, Pm46/Lr67/Yr46/Sr55, Pm？/Lr27/Yr30/ SY2 and Pm39/Lr46/Yr29, are not only resistant to powdery mildew but also effective for rust diseases in the field, indicating that such genes are stable and useful in wheat breeding programmes. The summarized data also provide chromosome locations or linked markers for Pm resistance genes/QTLs. Markers linked to these genes can also be utilized to pyramid diverse Pm resis- tance genes/QTLs more efficiently by marker-assisted selection.

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.

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.

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.

Ribosome Inactivating Proteins from Plants Inhibiting Viruses

Many plants contain ribosome inactivating proteins (RIPs) with N-glycosidase activity, which depurinate large ribosomal RNA and arrest protein synthesis. RIPs so far tested inhibit replication of mRNA as well as DNA viruses and these proteins, isolated from plants, are found to be effective against a broad range of viruses such as human immunodeficiency virus (HIV), hepatitis B virus (HBV) and herpes simplex virus (HSV). Most of the research work related to RIPs has been focused on antiviral activity against HIV; however, the exact mechanism of antiviral activity is still not clear. The mechanism of antiviral activity was thought to follow inactivation of the host cell ribosome, leading to inhibition of viral protein translation and host cell death. Enzymatic activity of RIPs is not limited to depurination of the large rRNA, in addition they can depurinate viral DNA as well as RNA. Recently, Phase I/II clinical trials have demonstrated the potential use of RIPs for treating patients with HIV disease. The aim of this review is to focus on various RIPs from plants associated with anti-HIV activity.

Epidemiology and gene markers of ulcerative colitis in the Chinese

Inflammatory bowel disease （IBD） includes two similar yet distinct conditions called ulcerative colitis （UC） and Crohn＇s disease （CD）. These diseases affect the digestive system and cause the inflammation of intestinal tissue, form sores and bleed easily. Most children with IBD are diagnosed in late childhood and adolescence. However, both UC and CD have been reported as early as in infancy. Most information pertaining to the epidemiology of IBD is based upon adult studies. Symptoms include abdominal pain, cramping, fatigue and diarrhea. Genetic factors play a significant role in determining IBD susceptibility. Epidemiological data support a genetic contribution to the pathogenesis of IBD. Recently, numerous new genes have been identified as being involved in the genetic susceptibility to IBD： TNF- 308A, CARD15 （NOD2）, MIF-173, N-acetyltransferase 2 （NAT2）, NKG2D （natural killer cell 2D）, STAT6 （signal transducer and activator of transcription 6）, CTLA-4 （cytotoxic T lymphocyte antigen-4）, MICA-MICB （major histocompatibility complex A and B）, HLA-DRB1, HLA class-Ⅱ, IL-18, IL-4, MICA-A5, CD14, TI R4, Fas-670, p53 and NF-kB. The characterization of these novel genes has the potential to identify therapeutic agents and aid clinical assessment of phenotype and prognosis in patients with IBD （UC and CD）.

Similar Neutralizing Activity in the HIV-1 Infected Long Term Non-progressors(LTNPs) and Typical Progressors(TPs)

Neutralizing antibodies are considered to be an important protective parameter used in HIV-1 vaccine evaluation. However, the exact role that neutralizing antibodies plays in controlling the disease progression of HIV-1 infected peoples is still undetermined. In this paper, we compared the protective function of the neutralizing antibody response in the plasma from LTNP and TP against clade B and clade C pseudoviruses. No difference in the neutralizing activities between the plasma from LTNP and TP was found, which was consistent with the most recent reports. In addition, no correlations between the titer or breadth and CD4+ or viral load in HIV-1 infected individuals were found. The protective roles played by neutralizing antibodies in controlling disease progression of HIV-1 infected people need to be considered in a new viewpoint.

An overview of occult hepatitis B virus infection

Occult hepatitis B virus (HBV) infection (OBI), alternatively defined as occult hepatitis B (OHB), is a challenging clinical entity. It is recognized by two main characteristics: absence of HBsAg, and low viral replication. The previous two decades have witnessed a remarkable progress in our understanding of OBI and its clinical implications. Appropriate diagnostic techniques must be adopted. Sensitive HBV DNA amplification assay is the gold standard assay for detection of OBI. Viral as well as host factors are implicated in the pathogenesis of OBI. However, published data reporting the infectivity of OBI by transfusion are limited. Several aspects including OBI transmission, infectivity and its relation to the development of chronic liver diseases and hepatocellular carcinoma have to be resolved. The aim of the present review is to highlight recent data on OBI with a focus on its virological diagnosis and clinical outcome.

Prophylactic antibiotics for variceal hemorrhage: Clostridium difficile infection still can be a risk

Bron et al presented a retrospective study regarding the prophylactic use of antibiotics for variceal hemorrhage. Antibiotics appeared to improve the survival rate of patients without increasing clostridium difficile infection (CDI). We argue against the conclusion of the authors and consider that this result may be simply due to concurrent use of metronidazole, a therapeutic agent against CDI.

Immune response of Pseudosciaena crocea to the injection of Vibrio alginolyticus

For the investigation of anti-infection immune response of Pseudosciaena crocea, 160 healthy fish samples were categorized into infected and control groups. Each individual fish in the infected group was injected intraperitoneally (i.p.) with 0.2 ml bacterial suspension of Vibrio alginolyticus in density of 2×107 CFU/ml, while each individual in the control group was injected i.p. with 0.2 ml sterile saline solution (0.85%). It was observed that the artificial injection of V. alginolyticus significantly increased the number of erythrocytes, leucocytes, lymphocytes in peripheral blood as well as peripheral serum antibacterial activity and antibody titer of large yellow croaker, and significantly reduced the number of peripheral blood granulocytes as compared with those in the control group. No significant difference in acid phosphytase and superoxide dismutase activity of serum was detected between the two groups. It is suggested that non-specific immune factors including leucocytes and anti-bacteria substance in peripheral blood played important role at the initial stage of infection, and specific immune factors such as antibody then played important role in response to anti-infection at the latter stage.