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Structural modifications of Helicobacter pylori lipopolysaccharide:An idea for how to live in peace

World Journal of Gastroenterology 2014年第29期20卷 9882-9897页

作者： Magdalena Chmiela Karolina Rudnicka Eliza Miszczyk department of Immunology and Infectious biology Faculty of Biology and Environmental ProtectionUniversity of ?ód?

In this review, we discuss the findings and concepts underlying the “persistence mechanisms” of Helicobacter pylori (H. pylori), a spiral-shaped, Gram-negative rod bacterium that was discovered as a gastric pathogen by Marshall and Warren in 1984. H. pylori colonizes the gastric mucosa of nearly half of the human population. Infections appear in early childhood and, if not treated, persist for life. The presence or absence of symptoms and their severity depend on multiple bacterial components, host susceptibility and environmental factors, which allow H. pylori to switch between pathogenicity and commensalism. Many studies have shown that H. pylori components may facilitate the colonization process and the immune response of the host during the course of H. pylori infection. These H. pylori-driven interactions might result from positive or negative modulation. Among the negative immunomodulators, a prominent position is occupied by a vacuolating toxin A (VacA) and cytotoxin-associated gene A (CagA) protein. However, in light of the recent studies that are presented in this review, it is necessary to enrich this panel with H. pylori lipopolysaccharide (LPS). Together with CagA and VacA, LPS suppresses the elimination of H. pylori bacteria from the gastric mucosa by interfering with the activity of innate and adaptive immune cells, diminishing the inflammatory response, and affecting the adaptive T lymphocyte response, thus facilitating the development of chronic infections. The complex strategy of H. pylori bacteria for survival in the gastric mucosa of the host involves both structural modifications of LPS lipid A to diminish its endotoxic properties and the expression and variation of Lewis determinants, arranged in O-specific chains of H. pylori LPS. By mimicking host components, this phenomenon leaves these bacteria “invisible” to immune cells. Together, these mechanisms allow H. pylori to survive and live for many years within the

关键词： Helicobacter pylori Lipopolysaccharide Immune response Adaptation Inflammation

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Host pathogen interactions in Helicobacter pylori related gastric cancer

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World Journal of Gastroenterology 2017年第9期23卷 1521-1540页

作者： Magdalena Chmiela Zuzanna Karwowska Weronika Gonciarz Bujana Allushi Pawel Staczek department of Immunology and Infectious biology Institute of MicrobiologyBiotechnology and ImmunologyFaculty of Biology and Environmental ProtectionUniversity of Lodz department of Genetics of Bacteria Institute of MicrobiologyBiotechnology and ImmunologyFaculty of Biology and Environmental ProtectionUniversity of Lodz

Helicobacter pylori (H. pylori), discovered in 1982, is a microaerophilic, spiral-shaped gram-negative bacterium that is able to colonize the human stomach. Nearly half of the world’s population is infected by this pathogen. Its ability to induce gastritis, peptic ulcers, gastric cancer and mucosa-associated lymphoid tissue lymphoma has been confirmed. The susceptibility of an individual to these clinical outcomes is multifactorial and depends on H. pylori virulence, environmental factors, the genetic susceptibility of the host and the reactivity of the host immune system. Despite the host immune response, H. pylori infection can be difficult to eradicate. H. pylori is categorized as a group I carcinogen since this bacterium is responsible for the highest rate of cancer-related deaths worldwide. Early detection of cancer can be lifesaving. The 5-year survival rate for gastric cancer patients diagnosed in the early stages is nearly 90%. Gastric cancer is asymptomatic in the early stages but always progresses over time and begins to cause symptoms when untreated. In 97% of stomach cancer cases, cancer cells metastasize to other organs. H. pylori infection is responsible for nearly 60% of the intestinal-type gastric cancer cases but also influences the development of diffuse gastric cancer. The host genetic susceptibility depends on polymorphisms of genes involved in H. pylori-related inflammation and the cytokine response of gastric epithelial and immune cells. H. pylori strains differ in their ability to induce a deleterious inflammatory response. H. pylori-driven cytokines accelerate the inflammatory response and promote malignancy. Chronic H. pylori infection induces genetic instability in gastric epithelial cells and affects the DNA damage repair systems. Therefore, H. pylori infection should always be considered a pro-cancerous factor.

关键词： Helicobacter pylori Host susceptibility Carcinogenesis Bacterial diversity

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Molecular mimicry in Helicobacter pylori infections

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World Journal of Gastroenterology 2017年第22期23卷 3964-3977页

作者： magdalena chmiela weronika gonciarz department of immunology and infectious biology institute of microbiology biotechnology and immunology faculty of biology and environmental protection university of lodz

Gram-negative bacteria Helicobacter pylori(H. pylori) colonize gastric mucosa in humans and increase the risk of serious diseases such as gastric and duodenal ulcers, stomach cancers and mucosa associated lymphoid tissue lymphoma. The role of H. pylori infection in the pathogenesis of several extragastric diseases has been suggested including immune thrombocytopenic purpura, iron deficiency anemia, vitamin D deficiency, cardiovascular diseases,diabetes mellitus and dermatological disorders. Also neurological diseases and even lung cancer have attracted researchers concern. The relation between H. pylori infection and a growth retardation in children has also been suggested. Many mechanisms of molecular mimicry between H. pylori and the host have been proposed as a pathogen strategy to manipulate the immune system of the host in order to remain unrecognized and avoid eradication. A lot of effort has been put into the demonstration of homologous sequences between H. pylori and host compounds. However, knowledge about how often autoantibodies or autoreactive T lymphocytes induced during H. pylori infections cause pathological disorders is insufficient. This review provides data on H. pylori antigenic mimicry and possible deleterious effects due to the induction of immune response to the components common to these bacteria and the host.

关键词： Helicobacter pylori Molecular mimicry Anti-self response Extragastric effects

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Happy together？ Avoidance of conspecifics by gregarious mussels

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Current Zoology 2018年第1期64卷 53-61页

作者： Anna DZIERZYNSKA-BIALONCZYK Aleksandra SKRZYPCZAK Jaroslaw KOBAK Faculty of biology and environmental protection Department of Invertebrate Zoology Nicolaus CopernicusUniversity Lwowska 1 Torun 87-100 Poland

Zebra mussel Dreissena polymorpha is a Ponto-Caspian species invasive in Europe and North America, with great environmental impact. It lives byssally attached to hard substrata in large aggregations, which is often explained by its preferences for conspecifics, though direct evidence for such preferences has been rather limited so far. We studied the reactions of zebra mussels to con- specifics, hypothesizing that they may either be attracted to one another or form aggregations only in the absence of alternative attachment sites, in Experiment 1, we tested mussel tendency to detach from existing druses depending on druse size （2-25 individuals） and substratum type （soft： sand; hard： glass）. Mussels detached significantly more often on the hard substratum and from larger druses compared to soft substratum and smaller druses, respectively. This indicates that mussels tended to avoid conspecifics at high density, particularly when alternative substratum was available. In Experiment 2, we tested the responses of single mussels to distant （3 or 15cm） conspecifics （0, 3, 15 individuals per 2.51 tank） on the sandy substratum. The presence of conspecifics, regardless of their distance and density, resulted in single unattached mussels staying more often in their initial positions. Mussels did not move preferentially towards or away from the conspecifics. Thus, even on unsuitable substratum mussels were not attracted by conspecifics and probably exhibited an avoidance reaction by reducing their movement. This suggests that dense mussel aggregations are formed due to the lack of available alternative attachment sites rather than due to their preferences for conspecifics.

关键词： active detachment Dreissena polymorpha movement mussel aggregations zebra mussel.

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Soil application of Beauveria bassiana GHA against apple sawfly, Hoplocampa testudinea （Hymenoptera： Tenthredinidae）： Field mortality and fungal persistence

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Insect Science 2016年第6期23卷 854-868页

作者： Weronika Swiergiel Nicolai V. Meyling Mario Porcel Birgitta Ramert department of Plant protection biology Unit of Integrated Plant Protection Swedish University of Agricultural Sciences (SLU) AlnarpSweden department of Plant and environmental Sciences University of Copenhagen Copenhagen Denmark

Low impact alternatives to synthetic insecticides for the control of apple sawfly （Hoplocampa testudinea Klug） are scarce encumbering pest management in organic apple orchards. We investigated the soil persistence and field efficacy of the entomopathogenic fungus Beauveria bassiana （Balsamo） Vuillemin （BotaniGard） against apple sawfly under common organic orchard practices. We also assessed the efficacy of B. bassiana GHA and Metarhiziurn brunneum Petch （indigenous strain） against sawfly in the laboratory. Larvae treated with either fungus in the laboratory died faster than control larvae and displayed 49.4%-68.4% mycosis. In the field, B. bassiana density remained high in the week after application, during larval descent to the soil. Fungal density decreased to 25% at 49 d after application and to 0.4% after 55 weeks. Molecular markers revealed that the majority of fungal isolates recovered comprised the applied B. bassiana strain GHA. Larvae pupating in soil cages in the orchard for 49 d displayed 17% mycosis. The high efficacy under laboratory conditions was not seen in the field. B. bassiana application resulted in densities above the upper natural background level during the growing season, but reversion to background levels occurred within a year. It remains to be investigated whether this has a detrimental effect on nontarget organisms. Additional work is needed to bridge the knowledge gap between laboratory and field efficacy in orchards.

关键词： biological control crop protection entomopathogenic fungi integrated pest management Metarhizium organic orchard

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Removal of 17β-estradiol in laccase catalyzed treatment processes

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Frontiers of environmental Science & Engineering 2014年第3期8卷 372-378页

作者： Qing XIA Deyang KONG Guoqiang LIU Qingguo HUANG Aamr ALALEWI Junhe LU department of environmental Science and Engineering Nanjing Agricultural University Nanjing 210095 China Nanjing Institute of environmental Sciences Ministry of Environmental Protection Nanjing 210042 China department of crop and Soil Sciences University of Georgia Griffin GA 30223 USA

The removal of 17β-estradiol （E2） in laccase catalyzed oxidative coupling processes was systematically studied in this work. We focused on the influence of pH and natural organic matter （NOM） on the performance of the enzymatic treatment processes. It was found that the optimal pH for E2 removal was between 4 and 6. The removal of E2 was slightly inhibited in the presence of NOM. Enzymatic transformation of E2 was second-order in kinetics with first-order to both the concentrations of the enzyme and contaminant. Mass spectrum （MS） analysis suggested that coupling products were formed through radical-radical coupling mechanism. The results of this study demonstrated that laccase catalyzed oxidative coupling process could potentially serve as a treatment strategy to control steroid estrogens.

关键词： 17β-estradiol laccase oxidative coupling processes kinetics mechanisms

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Wheat streak mosaic virus： incidence in field crops, potential reservoir within grass species and uptake in winter wheat cultivars

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Journal of Integrative Agriculture 2017年第3期16卷 523-531页

作者： Jana Chalupniková Jiban Kumar Kundu Khushwant Singh Pavla Bartaková Eva Beoni Division of crop protection and Plant Health Crop Research Institute Prague 16106 Czech Republic department of Experimental Plant biology Faculty of Science Charles University in Prague Prague 12843 Czech Republic

Wheat streak mosaic virus（WSMV）has become a re-emerging pathogen in cereal crops in the Czech *** was first reported in the former Czechoslovakia in the early 1980s,and then no record of the virus was documented until *** incidence of the virus was recorded in recent years in several winter wheat fields and many grass ***,we surveyed the incidence of WSMV in cereal *** results demonstrated the existence of the virus in winter wheat and volunteer wheat during each year of the monitoring period,which spanned from 2013–*** the range of infected samples was low（6.4%of the total tested samples）,a high incidence of well-distributed virus was *** at least six fields,the virus reached severe and potentially epidemic *** accordance with our previous report detailing WSMV infection of native grasses,we tested several grass species commonly grown in the Czech *** found that some grass species acted as experimental hosts and possible reservoirs of the virus;these included Anthoxanthum odoratum（sweet vernal grass）,Arrhenatherum elatius（false oat-grass）,Lolium multiflorum（Italian rye-grass）,Bromus japonicus（Japanese chess）,Echinochloa crus-galli（barnyard grass）,Holcus lanatus（meadow soft grass）and Holcus mollis（creeping soft grass）.Some of these grass species are also important weeds of cereals,which may be the potential source of WSMV infection in cereal *** widely used winter wheat cultivars were tested in the field after artificial inoculation with WSMV to evaluate virus titre by ***,the tested cultivars had a low virus titre,which is associated with mild disease symptoms and may provide a good level of crop resistance to WSMV.

关键词： WSMV survey grass species cereal crops

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Remote sensing of bark beetle damage in Norway spruce individual tree canopies using thermal infrared and airborne laser scanning data fusion

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Forest Ecosystems 2022年第5期9卷 710-723页

作者： Agata Zakrzewska Dominik Kopec department of Biogeography Paleoecology and Nature ProtectionFaculty of Biology and Environmental ProtectionUniversity of LodzŁodzPoland MGGP Aero Sp.z o.o. TarnowPoland

Background:Increasing threat to Central Europe’s forests from the growing population of the European spruce bark beetle Ips typographus (L.) calls for developing highly effective methods of detection of the infestation spots. The main goal of this study was to establish an automatic workflow for detection of dead trees and trees in poor condition of Picea abies using Middle Wave Infrared spectral range obtained from the ***:The studies were conducted in Wigry National Park (Poland) in 2020. A fusion of aircraft thermal data and laser scanning was used. Synchronous with thermal data acquisition ground reference data were obtained for P. abies in different health conditions. Determination of the range of canopy temperatures characteristic of the three condition states (‘healthy’,‘poor condition’,‘dead’) was performed using K-mean clustering. The accuracy of the method was evaluated on two validation sets:(1) individual tree canopies determined by photointerpretation, and (2) automatic segmentation of laser scanning ***:The results showed that the average temperature of ‘healthy’trees was 27.70℃, trees in ‘poor condition’28.57℃, and ‘dead’trees 30.17℃. High temperature differences between ‘healthy’and ‘dead’P. abies made it possible to distinguish these two condition classes with high accuracy. Lower accuracies were obtained for the class of ‘poor condition’, which was found to be confusing with both ‘healthy’and ‘dead’trees. According to results from the first validation set, a high overall accuracy of 0.60 was obtained. For the second validation set, the overall accuracy was reduced by 11%.Conclusions:This study indicates that canopy temperature recorded from the airborne level is a variable that differentiates ‘healthy’spruces from those in ‘poor condition’and the ‘dead’trees. The results confirmed that thermal and airborne laser scanning data fusion allows for creating a quick and simple workflow, which can successfully separate individual tre

关键词： Infrared thermography Picea abies Ips typographus Middle wave infrared Forest invasion Forest health K-mean clustering

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Insecticide resistance of the field populations of oriental armyworm,Mythimna separata(Walker) in Shaanxi and Shanxi provinces of China

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Journal of Integrative Agriculture 2018年第7期17卷 1556-1562页

作者： ZHAO Yu-yu SU Li LI Shuai LI Yi-ping XU Xiang-li CHENG Wei-ning WANG Yi WU Jun-xiang State Key Laboratory of crop Stress biology in Arid Areas/College of Plant protection Northwest A&F University department of Plant protection Agricultural College Guangxi University College of Agriculture Shanxi Agricultural University

Resistance of five field populations of Mythimna separata（Walker） collected from Shaanxi and Shanxi provinces of China to six different insecticides was evaluated by leaf dip method in the laboratory. The results showed that all populations were relatively sensitive to emamectin benzoate with a resistance ratio（RR） of 0.583–1.583 folds. All populations showed susceptible or low level resistance to chlorantraniliprole and beta-cypermethrin. Compared with a relatively susceptible strain of M. separata, the resistance level of the whole populations ranged from susceptible to moderate to chlorpyrifos and lambda-cyhalothrin, moderate to high to phoxim（RR=19.367–70.100） except for population from Sanyuan County（RR=2.567）. Pair-wise correlation analysis among different insecticides indicated that chlorpyrifos has a significantly positive and significant correlation with emamectin benzoate. Chlorantraniliprole didn＇t have significant correlation with emamectin benzoate, chlorpyrifos and phoxim. Therefore, emamectin benzoate, chlorantraniliprole and beta-cypermethrin are recommended to control oriental armyworm. Meanwhile, to postpone the occurrence and development of insecticide resistance in Shaanxi and Shanxi provinces, alternative and rotational application of insecticides between chlorantraniliprole and emamectin benzoate or chlorpyrifos is necessary.

关键词： Mythimna separata(Walker) insecticides toxicity bioassay

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Boosting Seed Development as a New Strategy to Increase Cotton Fiber Yield and Quality

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Journal of Integrative Plant biology 2013年第7期55卷 572-575页

作者： Yong-Ling Ruan department of biology School of Environmental and Life SciencesThe University of Newcastle Australia Australia-China Research Centre for Crop ImprovementThe University of Newcastle

Cotton （Gossypium spp.） is the most important textile crop worldwide due to its cellulosic mature fibers, which are single-celled hairs initiated from the cotton ovule epidermis at anthesis. Research to improve cotton fiber yield and quality in recent years has been largely focused on identifying genes regulating fiber cell initiation, elonga- tion and cellulose synthesis. However, manipulating some of those candidate genes has yielded no effect or only a marginally positive effect on fiber yield or quality. On the other hand, evolutionary comparison and transgenic studies have clearly shown that cotton fiber growth is intimately controlled by seed development. Therefore,I propose that enhancing seed development could be a more effective and achievable strategy to increase fiber yield and quality.

关键词： Auxin cotton fiber seed development sugars seed maternal and filial tissues.

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