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Jean François Emard Pierre Andre Jean -Pierre Thouez Jean Mathieu Camil Boily Michel Beaudry Andree Cholette Yves Robitaille Remi Bouchard Nicolas Daoud Francine Veilleux Denis Gauvreau 《Water, air, and soil pollution》1994,72(1-4):251-264
Accepting as founded the hypothesis of a multifactorial origin for the Alzheimer's disease (AD), we explore the possible links between the geographical distribution of AD cases according to their birth place and the geochemical profile of the Saguenay-Lac-Saint-Jean (SLSJ) territory in the province of Québec. The method used for factor analysis of correspondances (FAC) and another one based on the differences between the residential and municipal geochemical concentrations (DRMC) have been used for this purpose. The geochemical matrix of SLSJ relates the highest concentrations of nickel, copper and zinc to the sector surrounding the Jonquière municipality. Moreover, high concentrations of iron, lead and manganese were found in the northern sector of the Lac Saint-Jean. The DRMC method corroborates this strong correlation between iron, lead and manganese. Furthermore, these concentrations do not differ from the north-american geochemical standards. No single geochemical element seems to be associate with the spatial distribution of cases. It is, however, still possible that a certain synergistic effect between two or several elements could be implied in the development of the disease. According to the results of the soil analysis, there does not seem to be any association between the spatial distribution of cases and the concentration of aluminum, a chemical element that has been thought to be implied in the etiology of AD. These results are compared with those obtained by other workers in the micronesian islands, where abnormally high frequencies of amyotrophic lateral sclerosis and parkinsonism dementia have already been observed. 相似文献
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A simple and specific real-time PCR assay based on TaqMan® technology has been developed for the identification of cultured tobacco (Nicotiana tabacum) in various commodities such as cigars, cigarettes and reconstituted tobacco. The TaqMan® assay targets a sequence of the putrescine N-methyltransferase gene family encoding an enzyme that plays a crucial role in the biosynthesis of nicotine. To reduce the possibility of false negatives, universal plant chloroplast primers were also used in a separate real-time PCR reaction to give indication if DNA is amplifiable in the matrix. The TaqMan® assay successfully identified tobacco in over 40 commercial tobacco products, while negative results were obtained from the assay for DNA extracted from a variety of other botanical products. In our study, two commercial DNA isolation kits were used, namely, the Qiagen DNeasy® Plant Mini kit and the Qiagen Gentra® Puregene® kit. They produced good quality DNAs in sufficient quantities for real-time PCR analysis. In a few cases, an additional purification step with the Promega DNA IQ™ system had to be implemented to obtain amplifiable DNA. 相似文献
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Klaus G. Tietjen Joachim F. Kluth Roland Andree Michael Haug Markus Lindig Klaus H. Müller Heinz J. Wroblowsky Achim Trebst 《Pest management science》1991,31(1):65-72
The QB binding niche of photosystem II is also the binding site for many different herbicides. In order to understand the mode of binding of the herbicides, a 3-dimensional model of the binding niche was constructed. The model was based upon a comparison of the known structure of the QB binding niche in purple bacteria with sequence and mutant data of the D-1 protein of photosystem II. Plastoquinone builds up hydrogen bonds to phenylalanine 265 backbone amide nitrogen, to serine 264 hydroxyl, and to histidine 215 delta-1 nitrogen. In addition to these hydrogen bond donors and acceptors, herbicides can build up hydrogen bonds to backbone carbonyl of alamine 263 and to serine 268 hydroxyl. This is supported by binding data of inhibitors in Chlamydomonas reinhardtii chloroplasts of wild type and of five D-1 protein mutants (Ser264 Ala, Ala251 Val, Phe255Tyr, Val2191le, Leu275Phe). 相似文献
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Elena N. Kashinskaya Evgeniy P. Simonov Galina I. Izvekova Aleksey N. Parshukov Karl B. Andree Mikhail M. Solovyev 《Journal of fish diseases》2020,43(1):23-38
Using the approach of sequencing the V3-V4 region of the 16S rRNA gene, we have analysed the bacterial diversity associated with the distinct compartments of the gastrointestinal tract of perch (Perca fluviatilis) and cestodes (Proteocephalus sp.) parasitizing their digestive tract. The dominant microbiota associated with cestodes (Proteocephalus sp.) was represented by bacteria from the genera Serratia, Pseudomonas and Mycoplasma. By comparing the associated microbiota of perch and cestodes, a clear difference in bacterial composition and diversity was revealed between the community from the stomach content and other parts of the gastrointestinal tract of fish. Microbiota associated with cestodes was not significantly different in comparison with microbiota of different subcompartments of perch (mucosa and content of intestine and pyloric caeca) (ADONIS, p > .05) excluding microbiota of stomach content (ADONIS, p ≤ .05). PICRUSt-based functional assessments of the microbial communities of perch and cestodes indicated that they mainly linked in terms of metabolism and environmental information processing and could play an important role in the nutrition and health of host. 相似文献
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Inspections by customs agents at Barcelona airport discovered 420 kg of contraband glass eels prepared for shipment to Hong Kong. After confiscation of these animals by police, they were transported to holding facilities to be maintained until after a judicial hearing. Upon arrival, they were separated into two groups and held under ambient flow‐through conditions in fresh water. During their captivity period, several peaks in mortality occurred and multiple bacterial strains were isolated from moribund animals. Sequencing of 16S rDNA was used to determine specific identity of the isolates. An initial isolation of Pseudomonas anguilliseptica was treated with oxytetracycline. A subsequent isolation of Delftia acidovorans proved resistant to oxytetracycline and was treated with gentamicin in combination with sulphadiazine–trimethoprim. Once the health condition of the animals was stabilized, they were partitioned into groups and subsequently released as part of a restocking effort for the species following the guidelines of Regulation (EC) 1100/2007 (Anon 2007). This represents the first record for both bacterial species in the host Anguilla anguilla in the Spanish Mediterranean. 相似文献
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Sara R. Andree Zachary S. Feiner Jacob W. Bledsoe Aaron M. Cragun Tomas O. Höök 《Ecology of Freshwater Fish》2015,24(3):384-396
Maternal effects have been observed to interact with genotypic and environmental influences to structure offspring phenotypes across a wide variety of taxa. In fishes, maternal effects may be especially important due to their potential influence on development and survival during early ontogeny – a period with high potential for population regulation. While previous studies have confirmed that maternal effects on offspring phenotype are common in fishes, the consistency with which they positively affect offspring fitness throughout early ontogeny remains largely unknown. We examined maternal effects on offspring fitness by quantifying relationships between maternal (length, mass and age), egg (diameter, mass and density) and larval traits (length, yolk‐sac volume and survival) in yellow perch (Perca flavescens). Consistent with several past studies, positive relationships among maternal and egg traits were evident. While egg mass was positively related to larval size at hatching, direct relationships between maternal and larval metrics were not apparent. Larval survival appeared to have two critical periods; in contrast with expectations, survival in the first 5 days posthatch was strongly negatively related to female size and age, while survival over the following 9 days was unrelated to maternal traits. Throughout the study, survival was positively related to yolk‐sac volume. Our unexpected observation of a negative relationship between maternal size and age and initial larval survival indicates that maternal effects may not be consistent throughout larval ontogeny. In fact, maternal effects appear to be dynamic influences on offspring fitness, and may have complex effects on individual‐ and population‐level reproductive success. 相似文献
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LeRoy A Potter E Woo HH Heber D Hirsch AM 《Journal of agricultural and food chemistry》2002,50(18):5063-5069
The use of herbal remedies is very popular in the United States, with >80 million people buying plant-derived preparations that are often highly degraded or potentially contaminated with nonefficacious plant material. A method utilizing DNA-based markers to identify highly fragmented or powdered plant material sold as botanicals in dietary supplements has been developed. By incorporating and streamlining a repair reaction that utilized fill-in and ligation reactions before the PCR steps, it was possible to amplify highly degraded or sheared DNA isolated from powdered plant material removed from over-the-counter capsules. The primers for the internal transcribed spacer (ITS) region of nuclear ribosomal DNA generate a PCR fragment compatible with the sizes of the repaired DNA. Moreover, a large data set in Genbank facilitated subsequent analysis. This method is a relatively rapid and simple system to facilitate the authentication, as well as the monitoring, of the purity of botanicals in dietary supplements, even those that are improperly dried or stored. 相似文献
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Turbidity can fluctuate rapidly during the early life of fishes, impacting foraging behaviours. For piscivores, turbidity may hinder foraging, whereas planktivores and juvenile fishes may increase foraging activity and decrease antipredator behaviours in moderate levels of turbidity. Black crappie (Pomoxis nigromaculatus) and white crappie (P. annularis) population trends are often related to changes in turbidity. Yet effects of turbidity on juvenile foraging of these species are unknown and may differ between species. To evaluate effects of three turbidity levels (0, 25 and 50 NTU) on juvenile crappie foraging, controlled experiments compared (a) consumption and size selection for a single prey and (b) selection, total consumption and energetic value of diets when offered three distinct prey options. Overall, black crappies exhibited universally greater diet biomass than white crappies. Black crappies displayed higher prey consumption and were more size selective of a single‐prey type, whereas white crappies were less size selective and maintained uniform consumption as turbidity increased. Selection patterns for three prey types were similar among species and turbidity levels, with Chaoborus preferred and Chironomus avoided. However, black crappies also avoided Daphnia, whereas white crappies consumed them neutrally. Overall, turbidity did not impair foraging of juvenile crappies. Turbidity‐driven fluctuations in prey base paired with predator interactions likely also contribute to observed growth and abundance fluctuations in natural systems. 相似文献