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731.
Metal contaminations impact archaeal community composition,abundance and function in remote alpine lakes
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Sergi Compte‐Port Carles M. Borrego Hélène Moussard Mathilde Jeanbille Claudia Ximena Restrepo‐Ortiz Alberto de Diego Azibar Rodriguez‐Iruretagoiena Ainara Gredilla Silvia Fdez‐Ortiz de Vallejuelo Pierre E. Galand Dimitri Kalenitchenko Jean‐Luc Rols Oleg S. Pokrovsky Aridane G. Gonzalez Lluis Camarero Selene Muñiz Enrique Navarro‐Navarro Jean‐Christophe Auguet 《Environmental microbiology》2018,20(7):2422-2437
732.
733.
Carlos Polanco José Lino Samaniego Mendoza Thomas Buhse Vladimir N. Uversky Ingrid Paola Bañuelos Chao Marcela Angola Bañuelos Cedano Fernando Michel Tavera Daniel Michel Tavera Manuel Falconi Abelardo Vela Ponce de León 《Cell biochemistry and biophysics》2018,76(3):411-431
The number of fatalities and economic losses caused by the Ebola virus infection across the planet culminated in the havoc that occurred between August and November 2014. However, little is known about the molecular protein profile of this devastating virus. This work represents a thorough bioinformatics analysis of the regularities of charge distribution (polar profiles) in two groups of proteins and their functional domains associated with Ebola virus disease: Ebola virus proteins and Human proteins interacting with Ebola virus. Our analysis reveals that a fragment exists in each of these proteins—one named the “functional domain”—with the polar profile similar to the polar profile of the protein that contains it. Each protein is formed by a group of short sub-sequences, where each fragment has a different and distinctive polar profile and where the polar profile between adjacent short sub-sequences changes orderly and gradually to coincide with the polar profile of the whole protein. When using the charge distribution as a metric, it was observed that it effectively discriminates the proteins from their functional domains. As a counterexample, the same test was applied to a set of synthetic proteins built for that purpose, revealing that any of the regularities reported here for the Ebola virus proteins and human proteins interacting with Ebola virus were not present in the synthetic proteins. Our results indicate that the polar profile of each protein studied and its corresponding functional domain are similar. Thus, when building each protein from its functional domai—adding one amino acid at a time and plotting each time its polar profile—it was observed that the resulting graphs can be divided into groups with similar polar profiles. 相似文献
734.
Intra‐articular injection of autologous adipose‐derived mesenchymal stem cells in the treatment of knee osteoarthritis
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Duško Spasovski Vesna Spasovski Zoran Baščarević Maja Stojiljković Miša Vreća Marina Anđelković Sonja Pavlović 《The journal of gene medicine》2018,20(1)
Background
Osteoarthritis (OA) is a chronic degenerative joint disease and is considered to be the fourth leading cause of disability and the second cause of inability to work in men. Recently, adipose‐derived mesenchymal stem cells (AD‐MSCs) came into focus for regenerative medicine as a promising tool for the treatment of OA. The administration of stem cells into impaired joints results in pain relief and improves quality of life, accompanied by restoration of hyaline articular cartilage.Methods
In the present study, nine patients (including two patients with bilateral symptoms) diagnosed with osteoarthritis (International Knee Documentation grade B in 5 and grade D in six knees) were treated using a single injection of AD‐MSCs at a concentration of 0.5–1.0 × 107 cells and were followed up for 18 months. During follow‐up, all the cases were evaluated clinically by Knee Society score (KSS), Hospital for Special Surgery knee score (HSS‐KS), Tegner–Lysholm (T–L) score and visual analogue scale (VAS) of pain, as well as by plain radiography and by magnetic resonance imaging visualization with 2D Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score assessment.Results
Significant improvement of all four clinical scores was observed within the first 6 months (KSS for 41.4 points, HSS‐KS for 33.9 points, T–L score for 44.8 points, VAS of pain from 54.5 to 9.3) and improvement persisted throughout the rest of the follow‐up. MOCART score showed significant cartilage restoration (from 43 ± 7.2 to 63 ± 17.1), whereas radiography showed neither improvement, nor further joint degeneration.Conclusions
The results obtained in the present study provide good basis for prospective randomized controlled clinical trials with respect to the use of AD‐MSCs in the treatment of osteoarthritis. 相似文献735.
Hong-Xia Zhang Xiu-Shi Zhang Zi-Xiang Kuai Yang Zhou Yun-Feng Sun Zhi-Chang Ba Kuang-Bang He Xi-Qiao Sang Yuan-Fei Yao Chun-Yu Chu Yue-Min Zhu 《Translational oncology》2018,11(6):1370-1378
PURPOSE: To distinguish hepatocellular carcinoma (HCC) from other types of hepatic lesions with the adaptive multi-exponential IVIM model. METHODS: 94 hepatic focal lesions, including 38 HCC, 16 metastasis, 12 focal nodular hyperplasia, 13 cholangiocarcinoma, and 15 hemangioma, were examined in this study. Diffusion-weighted images were acquired with 13 b values (b?=?0, 3, …, 500 s/mm2) to measure the adaptive multi-exponential IVIM parameters, namely, pure diffusion coefficient (D), diffusion fraction (fd), pseudo-diffusion coefficient (Di*) and perfusion-related diffusion fraction (fi) of the ith perfusion component. Comparison of the parameters of and their diagnostic performance was determined using Mann-Whitney U test, independent-sample t test, one-way analysis of variance, Z test and receiver-operating characteristic analysis. RESULTS: D, D1* and D2* presented significantly difference between HCCs and other hepatic lesions, whereas fd, f1 and f2 did not show statistical differences. In the differential diagnosis of HCCs from other hepatic lesions, D2* (AUC, 0.927) provided best diagnostic performance among all parameters. Additionally, the number of exponential terms in the model was also an important indicator for distinguishing HCCs from other hepatic lesions. In the benign and malignant analysis, D gave the greatest AUC values, 0.895 or 0.853, for differentiation between malignant and benign lesions with three or two exponential terms. Most parameters were not significantly different between hypovascular and hypervascular lesions. For multiple comparisons, significant differences of D, D1* or D2* were found between certain lesion types. CONCLUSION: The adaptive multi-exponential IVIM model was useful and reliable to distinguish HCC from other hepatic lesions. 相似文献
736.
Saber Delpasand Khabbazi Afsaneh Delpasand Khabbazi S. Fatih Özcan Allah Bakhsh Dilek Başalma Sebahattin Özcan 《Plant biotechnology reports》2018,12(4):273-282
Insect-resistant transgenic cotton has been commercialized for two decades. Most of the introduced cultivars express Bt gene(s) constitutively under the control of 35S promoter in whole-plant tissues. However, there have been other promoters considered by researchers to confine the toxin expression to targeted organ and tissues. We developed a triple-gene construct including GNA, cry1Ac and cp4 epsps genes. We attempted to confine cry1Ac expression to insect biting sites by cloning it to downstream of a wound-inducible promoter isolated from Asparagus officinalis (AoPR1). Moreover, to broaden the range of resistance, GNA was driven by the 35S promoter to target the sap-sucking insects like aphids which impose large losses in cotton production. To select the transformants in selection medium and for glyphosate tolerance, GNA and cry1Ac genes were accompanied with cp4 epsps gene. Two binary vectors harboring desired genes were constructed and utilized in the study (pGTGNAoC1AC and pGTGN35C1AC). Transformation of cultivar GSN-12 was carried out by employing Agrobacterium tumefaciens strain EHA105. Plantlets were primarily screened under glyphosate (N-phosphonomethyl glycine) selection pressure and subsequently subjected to molecular and biotoxicity assays. Introduction of cry1Ac and GNA to cotton plant conferred resistance to Spodoptera littoralis and Aphis gossypii Glover. Restriction of cry1Ac toxin protein to insect biting sites along with a plant lectin attributes significantly to insect pest management strategies. 相似文献
737.
Trophic niche width and overlap of two sympatric gulls in the southwestern mediterranean 总被引:5,自引:0,他引:5
Jacob González-Solís Daniel Oro Lluis Jover Xavier Ruiz Vittorio Pedrocchi 《Oecologia》1997,112(1):75-80
The diets of two potential competitor species, Audouin's Larus audouinii and yellow-legged gulls Larus cachinnans, were examined while they bred at the Chafarinas Islands during 1993, 1994, and 1995. Data were collected during two commercial
fishing regimes: (1) trawling and purse seine fisheries, and (2) diurnal trawlers only. Since the food supply for the gulls
in this area was heavily reliant on the activity of purse seine fisheries, these contrasting situations allowed us to analyze
short-term effects, induced by daily changes in food supply, on niche width, dietary shift, and niche overlap between the
two species. Overall, both species relied mainly on fish for food, especially Clupeiforms, in the case of Audouin's gull irrespective
of the fishing situation, and in the case of the yellow-legged gull, only when purse seine fishing was in operation. When
purse seine boats did not operate (food shortage), yellow-legged gulls broadened their niche, consuming equal amounts of all
the feeding resources, and they showed a dietary shift toward a greater consumption of prey from refuse tips. In contrast,
Audouin's gulls did not change their niche width, but showed a slight dietary shift away from the consumption of epipelagic
fish, compensated by an increase in reliance on benthic-mesopelagic resources. Niche overlap was clearly higher on days when
both fishing fleets operated, probably because a superabundant food resource facilitates high overlap without affecting coexistence
between the two species. Since our study was developed on the basis of daily variations in food supply, and competition effects
are to be expected on a longer-term basis, these changes can be seen as the outcome of the coexistence of two species in stable
competitive equilibrium.
Received: 4 October 1996 / Accepted: 20 May 1997 相似文献
738.
Pavol Sulo Daniela Hudecová Antónia Propperová Ivan Bašnák 《Biotechnology Techniques》1996,10(6):413-418
Summary We present a rapid method for the direct analysis of poly--hydroxybutyrate (PHB) content in the soil bacteria Alcaligenes eutrophus. PHB from the fresh cells was converted by sulfuric acid to the crotonic acid and measured by capillary isotachophoresis after the neutralization by CaCO3. The method can be used for rapid and routine monitoring of the fermentation processes in samples containing 0.001 to 20 mg of PHB. 相似文献
739.
Eggs, larval and nymphal periods and fecundity of Pullus mediterraneus were examined under 16 h light : 8 h dark combined with six constant temperatures: 15, 20, 25, 30, 35 and 40°C. Eggs of Saissetia oleae were used as prey. The developmental time at 15, 20, 25, 30 and 35°C was 17.23, 4.5, 2.64, 1.67, 1.28 days for eggs and 98.47, 68.88, 53.94, 28.96, 36.51 days for larval–pupal duration, respectively. At 7°C no eggs hatched, and at 40°C all the stages died after 36 h of maximum exposure except the three last stages. The fecundity of females rearing at different temperatures ranged between 1.7 eggs at 15°C and 601.86 eggs at 30°C. The pre-oviposition period ranged between 23.75 days at 15°C and 3.47 days at 35°C. The consumption of S. oleae eggs by the larvae reached 597.69 eggs during the pre-imaginal development. Females attacked more eggs than males averaging 77.69 ± 22.34 eggs per 4 day period compared with 46.97 ± 10.12 eggs per 4 day period for males. 相似文献
740.
An Efficient Rice Transformation System Utilizing Mature Seed-derived Explants and a Portable,Inexpensive Particle Bombardment Device 总被引:1,自引:0,他引:1
Sudhakar Durailagaraja Duc Le Tan Bong Bui Ba Tinjuangjun Porntip Maqbool Shahina Bano Valdez Marta Jefferson Richard Christou Paul 《Transgenic research》1998,7(4):289-294
We developed a practical and efficient gene transfer system for indica rice utilizing mature-seed derived explants and a simple bombardment device which uses compressed helium for accelerating DNA-coated metal particles. Unlike instruments which have been described in the literature previously, this new bombardment device, which is an improvement of the particle inflow concept, does not require vacuum. This attribute simplifies the transformation procedure significantly and it makes rice transformation technology accessible to laboratories which may not have the resources to invest in more expensive particle bombardment instruments. We determined experimentally that we could recover transgenic rice plants utilizing three different particle bombardment instruments at comparable frequencies. 相似文献