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Does cypermethrin affect enzyme activity, respiration rate and walking behavior of the maize weevil （Sitophilus zeamais）？

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Insect Science 2013年第3期20卷 358-366页

作者： Ronnie Von Santos Veloso Eliseu Jose G. Pereira Raul Narciso C. Guedes Maria Goreti A. Oliveira departamento de Entomologia departamento de bioquimica e Biologia Molecular Universidade Federal de Vicosa Brazil

Insecticides cause a range of sub-lethal effects on targeted insects, which are frequently detrimental to them. However, targeted insects are able to cope with insecti- cides within sub-lethal ranges, which vary with their susceptibility. Here we assessed the response of three strains of the maize weevil Sitophilus zeamais Motschulsky （Coleoptera.＂ Curculionidae） to sub-lethal exposure to the pyrethoid insecticide cypermethrin. We ex- pected enzyme induction associated with cypermethrin resistance since it would aid the resistant insects in surviving such exposure. Lower respiration rate and lower activity were also expected in insecticide-resistant insects since these traits are also likely to favor survivorship under insecticide exposure. Curiously though, cypermethrin did not affect ac- tivity of digestive and energy metabolism enzymes, and even reduced the activity of some enzymes （particularly for cellulase and cysteine-proteinase activity in this case）. There was strain variation in response, which may be （partially） related to insecticide resistance in some strains. Sub-lethal exposure to cypermethrin depressed proteolytic and mainly cellulolytic activity in the exposed insects, which is likely to impair their fitness. However, such exposure did not affect respiration rate and walking behavior of the insects （except for the susceptible strain where walking activity was reduced）. Walking activity varies with strain and may minimize insecticide exposure, which should be a concern, particularly if associated with （physiological） insecticide resistance.

关键词： insecticides insecticide resistance pyrethroids stored grain insect sub-lethal effects

Distribution of the related weevil species Sitophilus oryzae and S. zeamais in Brazil

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Insect Science 2013年第6期20卷 763-770页

作者： Alberto S. Correa Luiz Orlando de Oliveira Lucas S. Braga Raul Narciso C. Guedes departamento de Entomologia Universidade Federal de Vicosa Vicosa Brazil departamento de bioquimica e Biologia Molecular Universidade Federal de Vicosa Vicosa Brazil

The genus Sitophilus （Coleoptera： Curculionidae） encompasses species of great economic importance as stored grain pests worldwide. Among these species, the maize and the rice weevils （Sitophilus zeamais and Sitophilus oryzae, respectively） are partic- ularly important in warmer climates. These two weevils exhibit closely morphological and ecological resemblance making difficult their proper identification and recognition of their distribution in grain-producing regions. Both species are recorded in South America and particularly in Brazil, but their respective distribution and prevalence were not yet assessed in the region. Therefore, several insect samples throughout Brazil were collected and subjected to morphological identification using male genitalia and also using molec- ular identification with species-specific primers designed for clear recognition of both the species. The primers were designed for the specific amplification of a gene fragment of the cytochrome oxidase subunit I, which exhibited high specificity during our prelimi- nary experiments with insects from six populations of known species （either S. zeamais or S. oryzae）. Both identification strategies provided the same results indicating preva- lence of the maize weevil S. zeamais throughout the country. Two hypotheses may explain such prevalence：（i） the likely host preference ofS. zeamais for maize because this is the most cultivated cereal in Brazil, and （ii） the prevalence ofS. zeamais in tropical regions as compared with S. oryzae, which is more disseminated in subtropical and temperate regions.

关键词： cytochrome oxidase subunit I distribution maize weevil rice weevil South America

Effects of absolute fasting on reproduction and survival of the invasive apple snail Pomacea canaliculata in its native range

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Current Zoology 2016年第4期62卷 369-375页

作者： Nicolas E. TAMBURI Pablo R. MARTIN INBIOSUR (UNS-CONICET) Universidad Nacional del Sur Departamento de Biologla Bioquimica y Farmacia San Juan 670 8000 Bahia Blanca Argentina

A South American freshwater gastropod, the apple snail Pomacea canaliculata, has become a driver of ecosystemic changes in wetlands and an important rice pest after its introduction to various parts of the world, mainly Asia. The objective of this study was to study the effect of an abrupt interruption in food availability in the short term （up to 4 weeks） and long term （up to 8 months） on survival and re- productive activity. The main results indicate that short-term fasting mainly affects the survival of males, but only when they are raised together with females, probably due to a greater mate-searching activity that increases mortality in the individuals with lower reserves. The number of copulating snails or egg-laying females shows an abrupt drop when fasting and a rapid recovery after the food supply is restored. The strategy of discontinuing reproductive activity prioritizes energy conservation for the survival of the females. Interpopulation variation in resistance to starvation was observed in adults, which can be explained to some extent by the food availability that they experienced in their natural environment. No interpopulational differences in survival were seen in hatchlings. The mean maximum values of survival under starvation were 52.6 days in hatchlings and the 3.3% of adults survive over than 200 days, which may be a relevant trait in dispersal and establishment in new habitats.

关键词： absolute fasting reproduction invasive apple

Chlamydia trachomatis and sperm lipid peroxidation in infertile men

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Asian Journal of Andrology 2003年第1期5卷 47-49页

作者： A.Segnini M.I.Camejo F.Proverbio Centro de Biofisica y bioquimica Instituto Venezolano de Investigaciones Cientlficas VenezuelaDepartamento de Biologia de Organismos Universidad Simon Bolivar Miranda VenezuelaCentro de Biofisica y Bioquimica Instituto Venezolano de Investigaciones Cientificas Venezuela.

Aim: To relate the presence of anti-Chlamydial trachomatis IgA in semen with sperm lipid membrane peroxidation and changes in seminal parameters. Methods: Semen samples of the male partners of 52 couples assessed for undiagnosed infertility were examined for the presence of IgA antibody against C. trachomatis. The level of sperm membrane lipid peroxidation was estimated by determining the malondialdehyde (MDA) formation. Results: Sperm membrane of infertile males with positive IgA antibodies against C. trachomatis showed a higher level of lipid peroxidation than that of infertile males with negative IgA antibody (P<0.05). There was a positive correlation (P< 0.01) between the level of C. trachomatis antibody and the magnitude of sperm membrane lipid peroxidation. All the other tested semen parameters were found to be similar in the two groups. Conclusion: The activation of immune system by C. trachomatis may promote lipid peroxidation of the sperm membrane. This could be the way by which C. trachomatis affects fertility.

关键词： Chlamydia trachomatis lipid peroxidation spermatozoa male infertility

Targeting the guanine-based purinergic system in Alzheimer's disease

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Neural Regeneration Research 2017年第2期12卷 212-213页

作者： Débora Lanznaster Carla I.Tasca departamento de bioquimica Programa de Pos-graduacao em Neurociencias Centro de Ciencias Biologicas Universidade Federal de Santa Catarina Florianopolis Brazil

Alzheimer’s disease（AD）is the main cause of dementia worldwide and affects approximately 5%of people with 65 years or *** estimated increase in the elderly population suggests that cases of AD will rise in the next... 详细信息

关键词： Targeting the guanine-based purinergic system in Alzheimer’s disease

Rat Cerebrospinal Fluid Treatment Method through Cisterna Cerebellomedullaris Injection

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Neuroscience Bulletin 2018年第5期34卷 827-832页

作者： Thaina Garbino dos Santos Mery Stefani Leivas Pereira Diogo Losch Oliveira Laboratory of Cellular Neurochemistry Departamento de Bioquimica Instituto de Ciencias Basicas da Saude Universidade Federal do Rio Grande do Sul Porto Alegre RS 90035-003 Brazil

Drugs that lack the ability to cross the blood- brain barrier （BBB） need to be placed directly into the central nervous system. Our laboratory studies the involve- ment of the glutamatergic system in the aggressiveness of glioma, and some ligands of glutamate receptors cannot permeate the BBB. Here, glioma-implanted rats were treated by a technique that delivers ligands directly into the cerebrospinal fluid by puncture into the cisterna cerebel- lomedullaris. Rats were anesthetized and fixed in a rodent stereotactic device. The head was gently tilted downwards at an angle that allowed exposure of the cisterna. Injection into the cisterna was done freehand using a gingival needle coupled to a microsyringe. The efficiency of intracisternal injection was demonstrated using a methylene blue solu- tion. This type of injection is adaptable for any rodent model using small volumes of a variety of other drugs, and is an interesting method for neuroscience studies.

关键词： Neurobiology Neuroscience Drug administration Intracisternal injection Cisterna magna Cerebrospinal fluid treatment Central nervous system Surgical technique Rodent

How does zebrafish support new strategies for neuroprotection and neuroregeneration in hypoxia-related diseases?

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Neural Regeneration Research 2016年第7期11卷 1069-1070页

作者： Emerson S.Silva Joao Batista T.Rocha Diogo O.Souza Marcos M.Braga Programa de Pos-Graduacao em bioquimica Departamento de Bioquimica Instituto de ciencias basicas da saude Universidade Federal do Rio Grande do Sul Porto Alegre RS Brazil Programa de Pos-Graduacao em bioquimica Toxicologica Departamento de Bioquimica e Biologia Molecular Centro de ciencias Naturais e Exatas Universidade Federal de Santa Maria Santa MariaRS Brazil Instituto Nacional de Ciencia e Tecnologia em Excitotoxicidade e Neuroprotecao Universidade Federal do Rio Grande do Sul PortoAlegre RS Brazil

Hypoxia is a condition found commonly in several disorders,such as ischemia,asthma,anemia and neonatal *** subjected suddenly to high altitude or extreme exercise are also challenged to low oxygen（O2）*** the brain p... 详细信息

关键词： How does zebrafish support new strategies for neuroprotection and neuroregeneration in hypoxia-related diseases

The Strawberry Fruit Fra a Allergen Functions in Flavonoid Biosynthesis

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Molecular Plant 2010年第1期3卷 113-124页

作者： Cristina Munoz Thomas Hoffmann Nieves Medina Escobar Felix Ludemann Miguel A. Botella Victoriano Valpuesta Wilfried Schwab departamento de Biologia Molecular y bioquimica Universidad de Malaga 29071 Malaga Spain Biomolecular Food Technology Technische Universit~t M0nchen Hochfeldweg 1 85354 Freising Germany

The strawberry Fra a I allergen is a homolog of the major birch pollen allergen Bet v 1. It is synthesized by red ripe fruits of Fragaria x ananassa while white fruits of a mutant genotype, which is known to be tolerated by individuals affected by allergy, are devoid of it. Proteomic analyses have shown that Fra a 1 is down-regulated in the tolerated white- fruited genotype along with enzymes of the anthocyanin pigment pathway. In this study, we report the spatial and tem- poral expression of three Fra a genes that encode different isoforms, and the transient RNAi-mediated silencing of the Fra a genes in strawberry fruits of the red-fruited cultivar Elsanta with an ihpRNA construct. As a consequence of reduced levels of Fra a mRNAs, fruits were obtained that produced significantly decreased levels of anthocyanins and upstream metabolites. This effect is consistent with the parallel down-regulation of the phenylalanine ammonia lyase （FaPAL） and to a lesser extent of the chalcone synthase （FaCHS） transcript levels also found in these fruits. In naturally occurring white- fruited genotypes of F. chiloensis and F. vesca, Fra a transcript levels are higher than those of the red-fruited varieties, likely to compensate for the low expression levels of FaPAL and FaCHS in these mutant genotypes. The results demonstrate that Fra a expression is directly linked to flavonoid biosynthesis and show that the Fra a allergen has an essential biological function in pigment formation in strawberry fruit.

关键词： Fragaria flavonoid anthocyanin phenylpropanoid allergen pathogenesis-related proteins.

N-Linked Glycosylation of the p24 Family Protein p24δ5 Modulates Retrograde Golgi-to-ER Transport of K/HDEL Ligands in Arabidopsis

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Molecular Plant 2017年第8期10卷 1095-1106页

作者： Noelia Pastor-Cantizano Maria Jesus Garcia-Murria Cesar Bernat-Silvestre Maria Jesus Marcote Ismael Mingarro Fernando Aniento departamento de bioquimica y Biologia Molecular Universitat de Valencia 46100 Burjassot Spain Estructura de Recerca Interdisciplinar en Biotecnologia i Biomedicina (ERI BIOTECMED) Universitat de Valencia 46100 Burjassot Spain

The K/HDEL receptor ERD2 mediates the transport of soluble endoplasmic reticulum （ER）-resident proteins containing a C-terminal K/HDEL signal from the Golgi apparatus back to the ER via COPI （COat Protein I）-coated vesicles. Sorting of ERD2 within COPI vesicles is facilitated by p24 proteins. In Arabidop- sis, p24δ5 has been shown to interact directly with ERD2 via its luminal GOLD （GOLgi Dynamics） domain and with COPI proteins via its cytoplasmic C-terminal tail at the acidic pH of the Golgi apparatus. Several members of the p24 family in mammals and yeast have been shown to be glycosylated, but whether Arabidopsis p24 proteins are glycosylated and the role of the sugar moiety in p24 function remain unclear. Here, we show that Arabidopsis p24δ5 protein is N-glycosylated in its GOLD domain. Furthermore, we demonstrate that this post-translational modification is important for its coupled transport with p241β2 at the ER-Golgi interface, for its interaction with the K/HDEL receptor ERD2, and for retrograde transport of ERD2 and K/HDEL ligands from the Golgi apparatus back to the ER.

关键词： K/HDEL receptor COPI (COat Protein I) p24 proteins N-glycosylation