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61.
Cultivated surfaces of genetically modified (GM) crops increased year by year, becoming in 2012 more extensive in developed than in industrialized countries. Furthermore, it has been postulated that the plant is which leads to the selection of the microorganisms on its root exudates, creating specific conditions which in turn regulate the specific microbial structure of each plant. In this study, our main objective was to examine whether the introduction of transgenic maize herbicide-tolerant plants will impact the microbial structures that inhabit at the rhizosphere and rhizoplane with respect to conventional hybrid maize plants. Bacterial populations were determined (CFU/g) using four different semi-selective media. The bacterial genera isolated from the rhizoplane and rhizosphere were identified by sequencing its 16S ribosomal DNA. Although minor differences were found in bacterial populations, our results indicated that there was not a strong change of the microorganisms populations that interact at the rhizosphere of an either conventional hybrid or genetically modified maize. However, we found some bacteria that were only isolated in the either genetically modified [Chryseobacterium sp. (4.39%) and Micrococcus sp. (3.72%)] or conventional maize [Sphingobium sp. (13.17%) and Microbacterium sp. (14.81%)]. 相似文献
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Verteramo R Pierangeli A Calzolari E Patella A Recine N Mancini E Marcone V Masciangelo R Bucci M Antonelli G Degener AM 《Microbes and infection / Institut Pasteur》2006,8(9-10):2517-2521
In order to assess the frequency of different human papillomavirus (HPV) types in Rome and the association between HPV and behavioural characteristics, we tested cervical scrapes of a population of sexually active women referring to university clinics for routine gynaecologic care. The presence of HPV DNA was revealed by polymerase chain reaction on two genome regions (L1 and E6/E7) followed by sequencing. Thirty different HPV types were identified; HPV 16 was the most prevalent (14.18%), followed by HPV 53 (9.21%), HPV 58 (7.80%), HPV 6 and 66 (both 5.67%) whereas all the other genotypes ranged below 5%. In univariate analysis the characteristics significantly associated with HPV DNA detection were the youngest age (P<0.01), the high number of lifetime partners (P<0.001) and the smoking habit (P<0.01). In multiple logistic regression analyses, the characteristics significantly associated with HPV DNA detection remained the younger age and the higher number of lifetime sexual partners. This study may be interesting in order to evaluate the circulation of HPV genotypes in Italy and to add a contribution to anti-cancer vaccine development. 相似文献
64.
Carolina Ayumi Braghini Izabella Agostinho Pena Neshich Goran Neshich Fernanda Caroline Soardi Maricilda Palandi de Mello Vital Paulino Costa José Paulo Cabral de Vasconcellos Mônica Barbosa de Melo 《Gene》2013
Mutations in the myocilin gene (MYOC) account for most cases of autosomal dominant juvenile-onset open-angle glaucoma (JOAG), an earlier and more severe form of POAG. We accessed seven members of a Brazilian JOAG family by clinical and molecular investigation. Four out of seven family members were diagnosed with JOAG. All of these patients presented high intraocular pressure and two of them were bilaterally blind. The disease onset varied from 20 to 30 years old. There was a nine-year-old family member who had not yet manifested the disease, although he was also a carrier of the mutation. Ophthalmologic examination included: evaluation of the visual field and optic disc, intraocular pressure measurement, and gonioscopy. The three exons and intron/exon junctions of the MYOC gene were screened for mutations through direct sequencing of PCR-amplified DNA fragments. Mutation screening revealed an in-frame mutation in the third exon of the MYOC gene: an insertion of six nucleotides between the cDNA positions 1187 and 1188 (c.1187_1188insCCCAGA, p.D395_E396insDP). This mutation presented an autosomal dominant pattern of inheritance, segregating with the disease in four family members for three generations, and it was absent in 60 normal controls. We also performed a computational structure modeling of olfactomedin-like domain of myocilin protein and conducted in silico analysis to predict the structural changes in the myocilin protein due to the presence of the mutation. These findings may be important for future diagnosis of other presymptomatic family members, as well as for the increase of the panel of MYOC mutations and their effects on phenotype. 相似文献
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66.
Gilles Le Pennec Sophie Campana Erwan Jolivet Jean-Marc Vital Xavier Barreau Wafa Skalli 《Computer methods in biomechanics and biomedical engineering》2014,17(10):1086-1095
Minimally invasive surgeries aiming to restore fractured vertebral body are increasing; therefore, our goals were to create a 3D vertebra reconstruction process and design clinical indices to assess the vertebral restoration in terms of heights, angles and volumes. Based on computed tomography (CT)-scan of the vertebral spine, a 3D reconstruction method as well as relevant clinical indices were developed. First, a vertebra initial solution requiring 5 min of manual adjustments is built. Then an image processing algorithm places this solution in the CT-scan images volume to adjust the model's nodes. On the vertebral body's anterior and posterior parts, nine robust heights, volume and endplate angle measurement methods were developed. These parameters were evaluated by reproducibility and accuracy studies. The vertebral body reconstruction accuracy was 1.0 mm; heights and volume accuracy were, respectively, 1.2 and 179 mm3. In conclusion, a 3D vertebra reconstruction process requiring little user time was proposed as well as 3D clinical indices assessing fractured and restored vertebra. 相似文献
67.
Larrieta E Vega-Monroy ML Vital P Aguilera A German MS Hafidi ME Fernandez-Mejia C 《The Journal of nutritional biochemistry》2012,23(4):392-399
Several studies have revealed that physiological concentrations of biotin are required for the normal expression of critical carbohydrate metabolism genes and for glucose homeostasis. However, the different experimental models used in these studies make it difficult to integrate the effects of biotin deficiency on glucose metabolism. To further investigate the effects of biotin deficiency on glucose metabolism, we presently analyzed the effect of biotin deprivation on glucose homeostasis and on pancreatic islet morphology. Three-week-old male BALB/cAnN Hsd mice were fed a biotin-deficient or a biotin-control diet (0 or 7.2 μmol of free biotin/kg diet, respectively) over a period of 8 weeks. We found that biotin deprivation caused reduced concentrations of blood glucose and serum insulin concentrations, but increased plasma glucagon levels. Biotin-deficient mice also presented impaired glucose and insulin tolerance tests, indicating defects in insulin sensitivity. Altered insulin signaling was linked to a decrease in phosphorylated Akt/PKB but induced no change in insulin receptor abundance. Islet morphology studies revealed disruption of islet architecture due to biotin deficiency, and an increase in the number of α-cells in the islet core. Morphometric analyses found increased islet size, number of islets and glucagon-positive area, but a decreased insulin-positive area, in the biotin-deficient group. Glucagon secretion and gene expression increased in islets isolated from biotin-deficient mice. Our results suggest that biotin deficiency promotes hyperglycemic mechanisms such as increased glucagon concentration and decreased insulin secretion and sensitivity to compensate for reduced blood glucose concentrations. Variations in glucose homeostasis may participate in the changes observed in pancreatic islets. 相似文献
68.
Francesca Happé Pedro Vital 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2009,364(1522):1369-1375
In this paper, we explore the question, why are striking special skills so much more common in autism spectrum conditions (ASC) than in other groups? Current cognitive accounts of ASC are briefly reviewed in relation to special skills. Difficulties in ‘theory of mind’ may contribute to originality in ASC, since individuals who do not automatically ‘read other minds’ may be better able to think outside prevailing fashions and popular theories. However, originality alone does not confer talent. Executive dysfunction has been suggested as the ‘releasing’ mechanism for special skills in ASC, but other groups with executive difficulties do not show raised incidence of talents. Detail-focused processing bias (‘weak coherence’, ‘enhanced perceptual functioning’) appears to be the most promising predisposing characteristic, or ‘starting engine’, for talent development. In support of this notion, we summarize data from a population-based twin study in which parents reported on their 8-year-olds'' talents and their ASC-like traits. Across the whole sample, ASC-like traits, and specifically ‘restricted and repetitive behaviours and interests’ related to detail focus, were more pronounced in children reported to have talents outstripping older children. We suggest that detail-focused cognitive style predisposes to talent in savant domains in, and beyond, autism spectrum disorders. 相似文献
69.
J Julien J M Vallat C Vital A Lagueny D Darriet 《Comptes rendus des séances de la Société de biologie et de ses filiales》1980,174(4):413-422
An adrenomyeloneuropathy is observed in a patient died at 24 years old after an illness of five years duration. These case is peculiar by the presence of lamellar cytoplasmic inclusions in the Schwann cells. Adrenomyeloneuropathy is an adult variant of adrenoleucodystrophy. This sex linked recessive disorder is related to an excessive amount of long chain fatty acids. 相似文献
70.
Didier Bompangue Patrick Giraudoux Martine Piarroux Guy Mutombo Rick Shamavu Bertrand Sudre Annie Mutombo Vital Mondonge Renaud Piarroux 《PLoS neglected tropical diseases》2009,3(5)