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963.
Xitlali Aguirre-Dugua Edgar Pérez-Negrón Alejandro Casas 《Journal of ethnobiology and ethnomedicine》2013,9(1):76
Background
Selection criteria are important for analyzing domestication of perennial plant species, which experience a selection pressure throughout several human generations. We analyze the preferred morphological characteristics of Crescentia cujete fruits, which are used as bowls by the Maya of Yucatan, according to the uses they are given and the phenotypic consequences of artificial selection between one wild and three domesticated varieties.Methods
We performed 40 semi-structured interviews in seven communities. We calculated Sutrop’s salience index (S) of five classes of ceremonial and daily life uses, and of each item from the two most salient classes. We sampled 238 bowls at homes of people interviewed and compared their shape, volume and thickness with 139 fruits collected in homegardens and 179 from the wild. Morphology of varieties was assessed in fruit (n?=?114 trees) and vegetative characters (n?=?136 trees). Differences between varieties were evaluated through linear discriminant analysis (LDA).Results
Use of bowls as containers for the Day of the Dead offerings was the most salient class (S?=?0.489) with chocolate as its most salient beverage (S?=?0.491), followed by consumption of daily beverages (S?=?0.423), especially maize-based pozol (S?=?0.412). The sacred saka’ and balche' are offered in different sized bowls during agricultural and domestic rituals. Roundness was the most relevant character for these uses, as bowls from households showed a strong selection towards round shapes compared with wild and homegarden fruits. Larger fruits from domesticated varieties were also preferred over small wild fruits, although in the household different sizes of the domesticated varieties are useful. LDA separated wild from domesticated trees (p?<?0.001) according to both fruit and vegetative variables, but domesticated varieties were not different among themselves.Conclusions
The association between C. cujete bowls and traditional beverages in ritual and daily life situations has driven for centuries the selection of preferred fruit morphology in this tree. Selection of fruit roundness and volume has allowed for the differentiation between the wild variety and the three domesticated ones, counteracting gene flow among them. By choosing the best fruits from domesticated varieties propagated in homegardens, the Maya people model the domestication process of this important tree in their culture.964.
965.
Background
The diagnosis of idiopathic pulmonary fibrosis can be quite challenging, even after careful clinical evaluation, imaging and pathological tests. This case report intends to demonstrate and discuss these difficulties, especially those concerning the differential diagnosis with chronic hypersensitivity pneumonitis.Case presentation
A 58-year-old white male presented with shortness of breath, dry cough, fatigue and weight loss for two months. He was a former smoker and had regular exposure to a parakeet and poultry. Physical examination revealed bilateral basal crackles and chest imaging showed subpleural cystic lesions and traction bronchiectasis with a right side and upper level predominance. Auto-antibodies and IgG immunoglobulins to parakeet and fungal proteins were negative. Lung function tests displayed moderate restriction, low diffusion capacity and resting hypoxaemia. Bronchoalveolar lavage showed increased lymphocytes (28%) and neutrophils (12%) and surgical lung biopsy was compatible with a pattern of usual interstitial pneumonia. According to the possibility of either idiopathic pulmonary fibrosis or chronic hypersensitivity pneumonitis, treatment included prednisolone, azathioprine, acetylcysteine and avoidance of contact with the parakeet, but there was an unfavorable response and the patient was subsequently referred for lung transplant.Conclusion
Chronic hypersensitivity pneumonitis and idiopathic pulmonary fibrosis can present with the same clinical and radiological manifestations In this case, despite careful evaluation, no definite diagnosis could be achieved.966.
Wei Xuan Evan Murphy Tom Beeckman Dominique Audenaert Ive De Smet 《Journal of chemical biology》2013,6(2):43-50
The application of small molecules has played a crucial role in identifying novel components involved in plant signalling. Compared to classic genetic approaches, small molecule screens offer notable advantages in dissecting plant biological processes, such as technical simplicity, low start-up costs, and most importantly, bypassing the problems of lethality and redundancy. To identify small molecules that target a biological process or protein of interest, robust and well-reasoned high-throughput screening approaches are essential. In this review, we present a series of principles and valuable approaches in small molecule screening in the plant model system Arabidopsis thaliana. We also provide an overview of small molecules that led to breakthroughs in uncovering phytohormone signalling pathways, endomembrane signalling cascades, novel growth regulators, and plant defence mechanisms. Meanwhile, the strategies to deciphering the mechanisms of these small molecules on Arabidopsis are highlighted. Moreover, the opportunities and challenges of small molecule applications in translational biology are discussed. 相似文献
967.
Issam Arrouss Fariba Nemati Fernando Roncal Marie Wislez Karim Dorgham David Vallerand Nathalie Rabbe Narjesse Karboul Fran?oise Carlotti Jeronimo Bravo Dominique Mazier Didier Decaudin Angelita Rebollo 《PloS one》2013,8(4)
Purpose
PP2A is a serine/threonine phosphatase critical to physiological processes, including apoptosis. Cell penetrating peptides are molecules that can translocate into cells without causing membrane damage. Our goal was to develop cell-penetrating fusion peptides specifically designed to disrupt the caspase-9/PP2A interaction and evaluate their therapeutic potential in vitro and in vivo.Experimental Design
We generated a peptide containing a penetrating sequence associated to the interaction motif between human caspase-9 and PP2A (DPT-C9h), in order to target their association. Using tumour cell lines, primary human cells and primary human breast cancer (BC) xenografts, we investigated the capacity of DPT-C9h to provoke apoptosis in vitro and inhibition of tumour growth (TGI) in vivo. DPT-C9h was intraperitonealy administered at doses from 1 to 25 mg/kg/day for 5 weeks. Relative Tumour Volume (RTV) was calculated.Results
We demonstrated that DPT-C9h specifically target caspase-9/PP2A interaction in vitro and in vivo and induced caspase-9-dependent apoptosis in cancer cell lines. DPT-C9h also induced significant TGI in BC xenografts models. The mouse-specific peptide DPT-C9 also induced TGI in lung (K-Ras model) and breast cancer (PyMT) models. DPT-C9h has a specific effect on transformed B cells isolated from chronic lymphocytic leukemia patients without any effect on primary healthy cells. Finally, neither toxicity nor immunogenic responses were observed.Conclusion
Using the cell-penetrating peptides blocking caspase-9/PP2A interactions, we have demonstrated that DPT-C9h had a strong therapeutic effect in vitro and in vivo in mouse models of tumour progression. 相似文献968.
Background
International collaboration (IC) is essential for the advance of stem cell research, a field characterized by marked asymmetries in knowledge and capacity between nations. China is emerging as a global leader in the stem cell field. However, knowledge on the extent and characteristics of IC in stem cell science, particularly China’s collaboration with developed economies, is lacking.Methods and Findings
We provide a scientometric analysis of the China–Canada collaboration in stem cell research, placing this in the context of other leading producers in the field. We analyze stem cell research published from 2006 to 2010 from the Scopus database, using co-authored papers as a proxy for collaboration. We examine IC levels, collaboration preferences, scientific impact, the collaborating institutions in China and Canada, areas of mutual interest, and funding sources. Our analysis shows rapid global expansion of the field with 48% increase in papers from 2006 to 2010. China now ranks second globally after the United States. China has the lowest IC rate of countries examined, while Canada has one of the highest. China–Canada collaboration is rising steadily, more than doubling during 2006–2010. China–Canada collaboration enhances impact compared to papers authored solely by China-based researchers This difference remained significant even when comparing only papers published in English.Conclusions
While China is increasingly courted in IC by developed countries as a partner in stem cell research, it is clear that it has reached its status in the field largely through domestic publications. Nevertheless, IC enhances the impact of stem cell research in China, and in the field in general. This study establishes an objective baseline for comparison with future studies, setting the stage for in-depth exploration of the dynamics and genesis of IC in stem cell research. 相似文献969.
Kayigan Wilson d’Almeida Dominique Pateron Gérald Kierzek Bertrand Renaud Caroline Semaille Pierre de Truchis Fran?ois Simon Judith Leblanc France Lert Stéphane Le Vu Anne-Claude Crémieux 《PloS one》2013,8(4)
Objective
We assessed the EDs’ characteristics associated with the offer and acceptance rates of a nontargeted HIV rapid-test screening in 29 Emergency Departments (EDs) in the metropolitan Paris region (11.7 million inhabitants), where half of France’s new HIV cases are diagnosed annually.Methods
EDs nurses offered testing to all patients 18–64-year-old, able to provide consent, either with or without supplemental staff (hybrid staff model or indigenous staff model). The EDS’ characteristics collected included structural characteristics (location, type, size), daily workload (patients’ number and severity, length of stay in hours), staff’s participation (training, support to the intervention, leadership), type of week day (weekends vs weekdays) and time (in days). Associations between these variables and the staff model, the offer and acceptance rates were studied using multilevel modeling.Results
Indigenous staff model was more frequent in EDs with a lower daily patient flow and a higher staff support score to the intervention. In indigenous-model EDs, the offer rate was associated with the patient flow (OR = 0.838, 95% CI = 0.773–0.908), was lower during weekends (OR = 0.623, 95% CI = 0.581–0.667) and decreased over time (OR = 0.978, 95% CI = 0.975–0.981). Similar results were found in hybrid-model EDs. Acceptance was poorly associated with EDs characteristics in indigenous-model EDs while in hybrid-model EDs it was lower during weekends (OR = 0.713, 95% CI = 0.623–0.816) and increased after the first positive test (OR = 1.526, 95% CI = 1.142–2.038).The EDs’ characteristics explained respectively 38.5% and 15% of the total variance in the offer rate across indigenous model-EDs and hybrid model-EDs vs 12% and 1% for the acceptance rate.Conclusion
Our findings suggest the need for taking into account EDs’ characteristics while considering the implementation of an ED-based HIV screening program. Strategies allowing the optimization of human resources’ utilization such as HIV targeted screening in the EDs might be privileged. 相似文献970.
Thi My Lien Do Anh Vu Truong Thi Nga Vo Travis G. Pinnock Lawrence M. Pratt Dominique Guillaume Kim Phi Phung Nguyen 《Phytochemistry letters》2013,6(4):544-551
Boerhaavia diffusa L. is used in the traditional medicine of several Asian countries. The isolation and identification of five new compounds, together with 11 known compounds, from the ethyl acetate extract of the aerial part of B. diffusa grown Vietnam is reported. The structure of the new compounds was established by 1D and 2D NMR spectroscopy, and high resolution ESI-MS analysis. New compounds are two rotenoids: 9,11-dihydroxy-6,10-dimethoxy[1]benzopyrano[3,4-b][1]benzopyran-12(6H)-one (boeravinone P, 3) and 3-[2-(β-d-glucopyranosyloxy)-3-hydroxyphenyl]-5-hydroxy-2-hydroxymethyl-7-methoxy-6-methyl-4H-1-benzopyran-4-one (boeravinone Q, 9), an atropisomeric mixture of two rotenoid glycosides (3′,5-dihydroxy-2-hydroxymethyl-7-methoxy-6-methylisoflavone 2′-O-β-d-glucopyranoside, 11), a sesquiterpene lactone (4,10-dihydroxy-8-methoxyguai-7(11)-en-8,12-olide, 5) and a new phenylpropanoid glycoside (boerhaavic acid, 15). 相似文献