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51.
52.
M. Ferchichi R. Valcheva N. Oheix P. Kabadjova H. Prévost B. Onno X. Dousset 《World journal of microbiology & biotechnology》2008,24(11):2425-2434
The aim of the present research is to identify rapidly the lactic acid bacteria (LAB) microflora of four natural French sourdoughs
(GO, BF, VB and RF), applying a biphasic (restriction length polymorphism (RFLP) and sequencing) approach for bacterial identification.
For this purpose, a database with the RFLP patterns of 30 lactobacilli type strains was created. So-developed ISR-RFLP algorithm
was further applied for the differentiation and identification of 134 sourdough isolates. The 16S-23S rDNA intergenic spacer
region was amplified by primers tAla and 23S/10, and then digested by HindIII, HinfI and α-TaqI enzymes. Nucleotide sequences of the cloned 16S-23S intergenic spacer region (ISR) were determined by the dideoxynucleotide
chain termination method. The T7Prom and M13rev primers flanking the multiple cloning site of pCR2.1 DNA were used to sequence
both DNA strands. The RFLP profile obtained upon digestion with HindIII, HinfI and α-TaqI enzymes can be used to discriminate Lactobacillus sanfranciscensis (66%), Lactobacillus
panis (17%), Lactobacillus nantensis (11%) and Lactobacillus hammesii(6%) in sourdough GO, Lactobacillus sanfranciscensis (80%), Lactobacillus spicheri (14%) and Lactobacillus pontis(6%) in sourdoughs BF. In sourdoughs VB, which differed in the process temperature, we can differentiate Lactobacillus sanfranciscensis (89%) and Leuconostoc mesenteroidessubsp. mesenteroides (11%). Lactobacillus frumenti(47%), Lactobacillus hammesii (8%), and Lactobacillus paralimentarius (45%) were differentiated in sourdough RF. 相似文献
53.
Birgit Knebel Stefan Lehr Onno E. Janssen Susanne Hahn Sylvia Jacob Ulrike Nitzgen Dirk Müller-Wieland Jorg Kotzka 《Molecular biology reports》2017,44(1):51-61
Polygenic diseases with a broad phenotypic spectrum, such as polycystic ovary syndrome (PCOS), present a particular challenge in terms of identifying the underlying genetic mechanisms, nevertheless genetic variants have impact on the individual phenotype. We aimed to determine if next to genetic variations like SNPs further mechanisms might play a role in the pathogenesis of PCOS. We examined the effect of copy-number variations (CNVs) on metabolic phenotypes in PCOS. The intragenic rs1244979, rs2815752 in NEGR1 gene, and rs780094 in GCKR gene were genotyped and CNVs were determined by droplet digital polymerase chain reaction (ddPCR) in PCOS patients (n?=?153) and controls without metabolic syndrome (n?=?142). The study indicated that SNPs are not associated with the pathogenesis of PCOS but affect metabolic phenotypes. The CNVs investigated show a lower variability in PCOS than in CON. Furthermore, we provided direct evidence that the copy number, but not the genotype of the CNV in the genomic regions of rs780094(GCKR) is associated with low level of high-density lipoprotein cholesterol in PCOS. This study supports the hypothesis that not only genetic variants, but also CNVs in metabolically relevant genes, have an effect on metabolic phenotypes in our group of PCOS patients. 相似文献
54.
Different initial responses of the canopy herbivory rate in mature oak trees to experimental soil and branch warming in a soil‐freezing area 下载免费PDF全文
Plants and insects comprise more than 50% of known species on earth, and their interactions are of major importance in most natural ecosystems. To understand the mechanisms by which global warming affects plant–insect interactions in the canopy of mature cool‐temperate forests with a freeze–thaw cycle, we examined changes in the herbivory rate and leaf traits in oak Quercus crispula. From 2007 to 2009, we experimentally increased the temperature of the surrounding soil and canopy branches of mature oak trees by approximately 5°C using electric heating cables. Soil warming decreased the rate of herbivory in the canopy, whereas branch warming had no effect. The magnitude of the effect of soil warming on canopy herbivory varied. For the first year, the decrease was 32%, but this doubled (63%) in the third year. Branch warming did not affect canopy leaf traits; however, soil warming decreased the leaf nutritional quality by decreasing N and increasing the carbon:nitrogen (CN) ratio for three years. Additionally, soil warming increased total phenolics in the third year. Stepwise multiple regression models showed that among the leaf traits that were changed by soil warming, N explained the variation in herbivory for the first and second years, whereas total phenolics explained it for the third year. Our experimental results demonstrate that soil warming drives the rate of herbivory in the canopy of mature oak trees, and the magnitude of the soil warming effect was gradually enhanced during the initial three years. This suggests the importance of belowground temperature elevation in predicting the effect of global warming on plant–insect interactions in a forest canopy. 相似文献
55.
The articulation of the experience of distress in terms of prevailing cultural idioms is deemed a crucially important factor in the effectiveness of healing devices across the globe. This curative factor, however, is not easily attainable in multicultural settings where therapist and patient do not share the same world view or explanatory models. In the following case presentation we report a culturally sensitive employment of strategic therapy with an ultra-orthodox psychiatric patient in Jerusalem. Despite the enormous cultural gap between the parties, the therapists were sufficiently sensitive to the patient's mythic world to enable him to recast his traumatic experiences in the mold of key idioms of his cultural background. These idioms were amplified by providing the patient with a myth-congruent metaphor and manipulated to afford a dramatic resolution of his emotional conflict. In what follows we discuss the setting of the therapy, the patient's background and diagnosis and the course of treatment. Following a verbatim account of the last therapeutic session, in which the patient's self-reconstitution had been completed, we discuss the cultural idioms synthesized in the text and the pertinence of hypnotic and metaphoric therapies to multicultural settings. 相似文献
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57.
van Dobbenburgh J. Onno Kasbergen Carina Slootweg Piet J. Ruigrok Tom J. C. van Echteld Cees J. A. 《Molecular and cellular biochemistry》1996,163(1):247-252
This study was undertaken to validate the potential of 31P magnetic resonance spectroscopy (MRS) as a noninvasive alternative for transvenous endomyocardial biopsy in detecting cardiac allograft rejection. Donor hearts from either Lewis rats (L) or Brown-Norway rats (BN) were transplanted into the neck of L rats resulting in a non-rejecting group L-L and a rejecting group L-BN. L-L and L-BN rats were serially studied by means of 31P MRS from postoperatine day 1–8. In addition, rejection was confirmed by histology. A similar, marked decrease in phosphocreative/-adenosinetriphosphate (PCr/ATP) ratio from day 1–3 was observed in both L-L and L-BN hearts. This ratio levelled off on postoperative day 3 and remained depressed on subsequent postoperative days in both groups, although histology showed an increase in the severity of rejection in L-BN. However, the PCr signal/noise ratio in L-BN started to decrease after day 4, coinciding with the histologic evidence of severe rejection (score IV), whereas in L-L hearts (score 0) this ratio remained unaltered until day 8. Since high-energy phosphate metabolism is affected by the unloaded status of the heterotopically transplanted heart, irrespective of rejection, the PCr/ATP ratio appears not to be a specific marker for the detection of acute rejection in this model. In contrast, the PCr S/N ratio appears to be a specific and sensitive marker of acute rejection, but only in a late, severe stage. 相似文献
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59.
Marieke Hiemstra Marloes Kleinjan Onno C. P. van Schayck Rutger C. M. E. Engels Roy Otten 《PloS one》2014,9(1)
Although environmental smoking (i.e., paternal and maternal smoking, sibling smoking, and peer smoking) is one of the most important factors for explaining adolescent smoking behavior, not all adolescents are similarly affected. The extent to which individuals are vulnerable to smoking in their environment might depend on genetic factors. The aim of this study was to examine the interplay between environmental smoking and genes encoding components of the dopaminergic system (i.e., dopamine receptor D2, D4, and dopamine transporter DAT1) in adolescent smoking onset. Data from two longitudinal studies were used. Study 1 consisted of 991 non-smoking early adolescents (mean age = 12.52, SD = .57) whereas study 2 consisted of 365 non-smoking middle to late adolescents (mean age = 14.16, SD = 1.07) who were followed for 16 and 48 months, respectively. Logistic regression analyses were conducted using Mplus. In study 1, we found positive associations between parents'' and friends'' smoking at the first measurement and smoking status 16 months later. In study 2 we found a positive association between friends'' smoking and smoking onset 48 months later. Neither study demonstrated any interaction effects of the DRD2, DRD4, or DAT1 genotypes. In conclusion, the effects of environmental smoking on smoking onset are similar for adolescent carriers and non-carriers of these specific genes related to the dopaminergic system. 相似文献
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