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161.
Lethal congenital contractural syndrome type 2 (LCCS2) is caused by a mutation in ERBB3 (Her3), a modulator of the phosphatidylinositol-3-kinase/Akt pathway 下载免费PDF全文
Narkis G Ofir R Manor E Landau D Elbedour K Birk OS 《American journal of human genetics》2007,81(3):589-595
Lethal congenital contractural syndrome type 2 (LCCS2) is an autosomal recessive neurogenic form of arthrogryposis that is associated with atrophy of the anterior horn of the spinal cord. We previously mapped LCCS2 to 6.4 Mb on chromosome 12q13 and have now narrowed the locus to 4.6 Mb. We show that the disease is caused by aberrant splicing of ERBB3, which leads to a predicted truncated protein. ERBB3 (Her3), an activator of the phosphatidylinositol-3-kinase/Akt pathway--regulating cell survival and vesicle trafficking--is essential for the generation of precursors of Schwann cells that normally accompany peripheral axons of motor neurons. Gain-of-function mutations in members of the epidermal growth-factor tyrosine kinase-receptor family have been associated with predilection to cancer. This is the first report of a human phenotype resulting from loss of function of a member of this group. 相似文献
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Dimitrios Karussis Hagai Shor Julia Yachnin Naama Lanxner Merav Amiel Keren Baruch Yael Keren-Zur Ofra Haviv Massimo Filippi Panayiota Petrou Shalom Hajag Urania Vourka-Karussis Adi Vaknin-Dembinsky Salim Khoury Oded Abramsky Henri Atlan Irun R. Cohen Rivka Abulafia-Lapid 《PloS one》2012,7(12)
Background
T-cell vaccination (TCV) for multiple sclerosis (MS) refers to treatment with autologous anti-myelin T-cells, attenuated by irradiation. Previously published clinical trials have been all open-labeled.Aim
To evaluate the safety and efficacy of TCV in progressive MS, in a double-blind, controlled clinical trial.Methodology
Twenty-six patients with relapsing-progressive MS were enrolled in the study (mean age: 39±9.8 years; mean EDSS: 4.4±1.7). T-cell lines reactive to 9 different peptides of the myelin antigens, MBP, MOG and PLP were raised from the patients'' peripheral blood. The patients were randomized into two groups: 19 were treated with TCV (four subcutaneous injections of 10–30×106 T-cells, attenuated by irradiation, on days 1, 30, 90 and 180) and 7 patients were treated with sham injections. Twenty-four patients (17 in the TCV group and 7 in the placebo) were eligible for per-protocol analysis.Results
At one year following the inclusion, an increase in the EDSS (+0.50) and an increase in 10-meter walking time (+0.18 sec), were observed in the placebo group; in the TCV group there was a decrease in the EDSS (−0.44; p<0.01) and in the 10-meter walking time (0.84 sec; p<0.005). Sixteen of the 17 patients (94.1%) in the TCV group remained relapse-free during the year of the study, as compared to 42.9% in the placebo group (p = 0.01 and p = 0.03 with adjustment). The proportion of patients with any relapse during the year of the study in the TCV-group, was reduced by 89.6%., as compared to the placebo-treated group. MRI parameters did not change significantly.Conclusions
This is the first controlled, double-blind trial with TCV in progressive MS. The results demonstrate the feasibility and safety of the procedure, and provide significant indications of clinical efficacy. Further studies with larger groups of subjects are warranted.Trial Registration
ClinicalTrials.gov NCT01448252相似文献165.
Plotkin SR Bredella MA Cai W Kassarjian A Harris GJ Esparza S Merker VL Munn LL Muzikansky A Askenazi M Nguyen R Wenzel R Mautner VF 《PloS one》2012,7(4):e35711
Purpose
Patients with neurofibromatosis 1 (NF1), NF2, and schwannomatosis are at risk for multiple nerve sheath tumors and premature mortality. Traditional magnetic resonance imaging (MRI) has limited ability to assess disease burden accurately. The aim of this study was to establish an international cohort of patients with quantified whole-body internal tumor burden and to correlate tumor burden with clinical features of disease.Methods
We determined the number, volume, and distribution of internal nerve sheath tumors in patients using whole-body MRI (WBMRI) and three-dimensional computerized volumetry. We quantified the distribution of tumor volume across body regions and used unsupervised cluster analysis to group patients based on tumor distribution. We correlated the presence and volume of internal tumors with disease-related and demographic factors.Results
WBMRI identified 1286 tumors in 145/247 patients (59%). Schwannomatosis patients had the highest prevalence of tumors (P = 0.03), but NF1 patients had the highest median tumor volume (P = 0.02). Tumor volume was unevenly distributed across body regions with overrepresentation of the head/neck and pelvis. Risk factors for internal nerve sheath tumors included decreasing numbers of café-au-lait macules in NF1 patients (P = 0.003) and history of skeletal abnormalities in NF2 patients (P = 0.09). Risk factors for higher tumor volume included female gender (P = 0.05) and increasing subcutaneous neurofibromas (P = 0.03) in NF1 patients, absence of cutaneous schwannomas in NF2 patients (P = 0.06), and increasing age in schwannomatosis patients (p = 0.10).Conclusion
WBMRI provides a comprehensive phenotype of neurofibromatosis patients, identifies distinct anatomic subgroups, and provides the basis for investigating molecular biomarkers that correlate with unique disease manifestations. 相似文献166.
167.
Facilitation, competition, and vegetation patchiness: from scale free distribution to patterns 总被引:1,自引:0,他引:1
A new technique for the modeling of perennial vegetation patchiness in the arid/semiarid climatic zone is suggested. Incorporating the stochasticity that affects life history of seedlings and the deterministic dynamics of soil moisture and biomass, this model is flexible enough to yield qualitatively different forms of spatial organization. In the facilitation-dominated regime, scale free distribution of patch sizes is observed, in correspondence with recent field studies. In the competition controlled case, on the other hand, power-law statistics is valid up to a cutoff, and an intrinsic length scale appears. 相似文献
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The dispersal unit of wild wheat bears two prominent filaments called awns. The awns bend as they dry and straighten in a damp environment. This hygroscopic movement is explained by the orientation of the cellulose fibrils that build the cell wall, as follows. The stiff fibrils are embedded in a soft hygroscopic matrix. When the cell wall dries, the matrix shrinks but the fibrils do not. Therefore, the cell wall contracts in a direction perpendicular to the fibril orientation. Using X-ray scattering we identified a region at the base of the awn that contains fibrils aligned in all directions. This is the active part, which contracts as it dries and pulls the awn to a bent position. Cryo-scanning electron microscopy revealed sequential laminas which are rotated to form a nano-scale plywood construction, implying planar local order within the global isotropy. Water molecules absorbed into the matrix probably cause large microscopic distortions by expanding neighboring layers in perpendicular directions. This is thought to cause opening of tiny gaps between fiber layers, to facilitate the exchange and the transport of water through the cell wall, and thereby to increase the sensitivity of the actuating unit to moderate changes in humidity. 相似文献
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Resistance of pepper species (Capsicum annuum, C. baccatum, C. chinense, C. chacoense, and C. frutescens), cultivars and accessions to the root-knot nematodes Meloidogyne incognita race 2 and M. javanica, and their graft compatibility with commercial pepper varieties as rootstocks were evaluated in growth chamber and greenhouse experiments. Most of the plants tested were highly resistant to M. javanica but susceptible to M. incognita. Capsicum annuum AR-96023 and C. frutescens accessions as rootstocks showed moderate and relatively high resistance to M. incognita, respectively. In M. incognita-infested soil in a greenhouse, AR-96023 supported approximately 6-fold less nematode eggs per gram root and produced about 2-fold greater yield compared to a nongrafted commercial variety. The commercial variety grafted on AR-96023 produced a yield as great as the non-grafted variety in the root-knot nematode-free greenhouse. Some resistant varieties and accessions used as rootstocks produced lower yields (P < 0.01) than that of the non-grafted variety in the noninfested greenhouse. Use of rootstocks with nematode-resistance and graft compatibility may be effective for control of root-knot nematodes on susceptible pepper. 相似文献