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81.
Copy number variations (CNVs) are an important cause of ASD and those located at 15q11-q13, 16p11.2 and 22q13 have been reported as the most frequent. These CNVs exhibit variable clinical expressivity and those at 15q11-q13 and 16p11.2 also show incomplete penetrance. In the present work, through multiplex ligation-dependent probe amplification (MLPA) analysis of 531 ethnically admixed ASD-affected Brazilian individuals, we found that the combined prevalence of the 15q11-q13, 16p11.2 and 22q13 CNVs is 2.1% (11/531). Parental origin could be determined in 8 of the affected individuals, and revealed that 4 of the CNVs represent de novo events. Based on CNV prediction analysis from genome-wide SNP arrays, the size of those CNVs ranged from 206 kb to 2.27 Mb and those at 15q11-q13 were limited to the 15q13.3 region. In addition, this analysis also revealed 6 additional CNVs in 5 out of 11 affected individuals. Finally, we observed that the combined prevalence of CNVs at 15q13.3 and 22q13 in ASD-affected individuals with epilepsy (6.4%) was higher than that in ASD-affected individuals without epilepsy (1.3%; p<0.014). Therefore, our data show that the prevalence of CNVs at 15q13.3, 16p11.2 and 22q13 in Brazilian ASD-affected individuals is comparable to that estimated for ASD-affected individuals of pure or predominant European ancestry. Also, it suggests that the likelihood of a greater number of positive MLPA results might be found for the 15q13.3 and 22q13 regions by prioritizing ASD-affected individuals with epilepsy.  相似文献   
82.
Abstract Transfer of plasmid RP4p from introduced Pseudomonas fluorescens to a co-introduced recipient strain or to members of the indigenous bacterial population was studied in four different soils of varying texture planted with wheat. Donor and recipient strains showed good survival in the four soils throughout the experiment. The numbers of transconjugants found in donor and recipient experiments in two soils, Ede loamy sand and Löss silt loam were significantly higher in the rhizosphere than in corresponding bulk soil. In the remaining two soils, Montrond and Flevo silt loam, transconjugant numbers were not significantly higher in the rhizosphere than in the bulk soil.
The combined utilization of a specific bacteriophage eliminate the donor strain and the pat sequence as a specific marker to detect RP4p was found to be very efficient in detecting indigenous transconjugants under various environmental conditions. The numbers of indigenous transconjugants were consistently higher in rhizosphere than bull soil. A significant rhizosphere effect on transconjugant numbers of transconjugants were recovered from Flevo and Montrond silt loam; these soils possess characteristics such as clay or organic matter contents which may be favorable to conjugation.  相似文献   
83.

Rationale

Few studies have analyzed the association of socioeconomic and sociodemographic factors with asthma related outcomes in early childhood, including Fraction of exhaled Nitric Oxide (FeNO) and airway resistance (Rint). We examined the association of socioeconomic and sociodemographic factors with wheezing, asthma, FeNO and Rint at age 6 years. Additionally, the role of potential mediating factors was studied.

Methods

The study included 6717 children participating in The Generation R Study, a prospective population-based cohort study. Data on socioeconomic and sociodemographic factors, wheezing and asthma were obtained by questionnaires. FeNO and Rint were measured at the research center. Statistical analyses were performed using logistic and linear regression models.

Results

At age 6 years, 9% (456/5084) of the children had wheezing symptoms and 7% (328/4953) had asthma. Children from parents with financial difficulties had an increased risk of wheezing (adjusted Odds Ratio (aOR) = 1.63, 95% Confidence Interval (CI):1.18–2.24). Parental low education, paternal unemployment and child''s male sex were associated with asthma, independent of other socioeconomic or sociodemographic factors (aOR = 1.63, 95% CI:1.24–2.15, aOR = 1.85, 95% CI:1.11–3.09, aOR = 1.58, 95% CI:1.24–2.01, respectively). No socioeconomic or gender differences in FeNO were found. The risks of wheezing, asthma, FeNO and Rint measurements differed between ethnic groups (p<0.05). Associations between paternal unemployment, child''s sex, ethnicity and asthma related outcomes remained largely unexplained.

Conclusions

This study showed differences between the socioeconomic and sociodemographic correlates of wheezing and asthma compared to the correlates of FeNO and Rint at age 6 years. Several socioeconomic and sociodemographic factors were independently associated with wheezing and asthma. Child''s ethnicity was the only factor independently associated with FeNO. We encourage further studies on underlying pathways and public health intervention programs, focusing on reducing socioeconomic or sociodemographic inequalities in asthma.  相似文献   
84.
The double sigmoidal nature of the mouse pressure-volume (PV) curve is well recognized but largely ignored. This study systematically examined the effect of inflating the mouse lung to 40 cm H2O transrespiratory pressure (Prs) in vivo. Adult BALB/c mice were anesthetized, tracheostomized, and mechanically ventilated. Thoracic gas volume was calculated using plethysmography and electrical stimulation of the intercostal muscles. Lung mechanics were tracked during inflation-deflation maneuvers using a modification of the forced oscillation technique. Inflation beyond 20 cm H2O caused a shift in subsequent PV curves with an increase in slope of the inflation limb and an increase in lung volume at 20 cm H2O. There was an overall decrease in tissue elastance and a fundamental change in its volume dependence. This apparent "softening" of the lung could be recovered by partial degassing of the lung or applying a negative transrespiratory pressure such that lung volume decreased below functional residual capacity. Allowing the lung to spontaneously recover revealed that the lung required approximately 1 h of mechanical ventilation to return to the original state. We propose a number of possible mechanisms for these observations and suggest that they are most likely explained by the unfolding of alveolar septa and the subsequent redistribution of the fluid lining the alveoli at high transrespiratory pressure.  相似文献   
85.
86.
87.
A polarized cell: the root statocyte   总被引:2,自引:0,他引:2  
In the gravity-perceiving cells (statocytes), located in the centre of the root cap, polarity is expressed in the arrangement of the organelles since, in most genera, the nucleus and the endoplasmic reticulum are maintained at the opposite ends of each cell by actin. Polarity is also evident in the distribution of plasmodesmata, which are more numerous in the transverse walls than in the longitudinal walls. The centre of each statocyte is depleted of microtubules (they are only located at the periphery) but is occupied by numerous amyloplasts (statoliths), denser than the cytoplasm. The amyloplasts do not contribute to the inherent structural polarity since their position is dependent upon the gravity vector. This article focuses on new microscopic analyses and on data obtained from experiments performed in microgravity, which have contributed to our better understanding of the architecture of the actin web implicated in the perception of gravity. Depending upon the plant, the actin network seems to be formed of single filaments arranged in various ways, or, of thin bundles of actin filaments. The amyloplasts are enmeshed in this web of actin and their envelopes are associated with it, but they can have autonomous movement via myosin in the absence of gravity. From calculations of the value of the force necessary to move one amyloplast in the lentil root, and from videomicroscopy performed with living statocytes of maize roots, it is hypothesized that actin microfilaments could be orientated in an overall diagonal direction in the statocyte. These observations could help in understanding how slight amyloplast movements may trigger and transmit the gravitropic signal.  相似文献   
88.
Novak J  Lehuen A 《Cytokine》2011,53(3):263-270
iNKT cells, CD1d dependent natural killer T cells are a unique population of T cells. The capacity of iNKT cells to produce regulatory cytokines first provided an indication of their regulatory potential. Later on, in experimental models as well as in patients afflicted with an auto-immune disease, such as Type 1 diabetes mellitus, multiple sclerosis, and systemic lupus erythematosus along with others, a deficit in iNKT cell number was observed, suggesting the role these cells may possibly have in the prevention of auto-immune diseases. More importantly, experimental strategies which focused on increasing the volume or stimulation of iNKT cells in laboratory animals, demonstrated an improved level of protection against the development of auto-immune diseases. This article reviews the mechanism of protection against autoimmunity by iNKT cells, discusses the obstacles against and indications for the potential use of iNKT cell manipulation in the treatment of human auto-immune diseases.  相似文献   
89.

Background

Multiple system atrophy (MSA) is a progressive neurodegenerative disorder characterized by parkinsonism, cerebellar ataxia and autonomic dysfunction. Pathogenic mechanisms remain obscure but the neuropathological hallmark is the presence of α-synuclein-immunoreactive glial cytoplasmic inclusions. Genetic variants of the α-synuclein gene, SNCA, are thus strong candidates for genetic association with MSA. One follow-up to a genome-wide association of Parkinson''s disease has identified association of a SNP in SNCA with MSA.

Methodology/Findings

We evaluated 32 SNPs in the SNCA gene in a European population of 239 cases and 617 controls recruited as part of the Neuroprotection and Natural History in Parkinson Plus Syndromes (NNIPPS) study. We used 161 independently collected samples for replication. Two SNCA SNPs showed association with MSA: rs3822086 (P = 0.0044), and rs3775444 (P = 0.012), although only the first survived correction for multiple testing. In the MSA-C subgroup the association strengthened despite more than halving the number of cases: rs3822086 P = 0.0024, OR 2.153, (95% CI 1.3–3.6); rs3775444 P = 0.0017, OR 4.386 (95% CI 1.6–11.7). A 7-SNP haplotype incorporating three SNPs either side of rs3822086 strengthened the association with MSA-C further (best haplotype, P = 8.7×10−4). The association with rs3822086 was replicated in the independent samples (P = 0.035).

Conclusions/Significance

We report a genetic association between MSA and α-synuclein which has replicated in independent samples. The strongest association is with the cerebellar subtype of MSA.

Trial Registration

ClinicalTrials.gov NCT00211224. [NCT00211224]  相似文献   
90.
We previously reported that a 3-pyridinecarbonitrile analog with a furan substituent at C-5 and a 4-methylindol-5-ylamino substituent at C-4, 1, was a potent inhibitor of PKCθ (IC50 = 4.5 nM). Replacement of the C-5 furan ring of 1 with bicyclic heteroaryl rings, led to compounds with significantly improved potency against PKCθ. Analog 6b with a 4-methylindol-5-ylamino group at C-4 and a 5-[(4-methylpiperazin-1-yl)methyl]-1-benzofuran-2-yl group at C-5 had an IC50 value of 0.28 nM for the inhibition of PKCθ.  相似文献   
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