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991.
Qiuchi Wan Zhuo Zheng Kangyou Huang Erwan Guichoux Rémy J. Petit 《Tree Genetics & Genomes》2017,13(4):73
Subtropical East Asia harbours a large plant diversity that is often attributed to allopatric speciation in this topographically complex region characterized by a relative climate stability. Here, we use observations of Platycarya, a widespread subtropical Asian tree genus, to explore the consequences of past climate stability on species’ evolutionary history in subtropical China. This genus has a controversial taxonomy: while it is now prevailingly treated as monotypic, two species have been originally described, Platycarya strobilacea and P. longipes. Previous information from species distribution models, fossil pollen data and genetic data based on chloroplast DNA (cpDNA) were integrated with newly obtained genetic data from the two putative species. We used both cpDNA (psbA-trnH and trnL-F intergenic spacers, including a partial trnL gene sequence) and nuclear markers. The latter included sequences of the internal transcribed spacer region (ITS1–5.8S–ITS2) of the nuclear ribosomal DNA and random genomic single nucleotide polymorphisms. Using these nuclear genetic markers, we found interspecific genetic divergence fitting with the ‘two species’ scenario and geographically structured intraspecific variation. Using cpDNA markers, we also found geographically structured intraspecific variation. Despite deep inter- and intraspecific genetic divergence, we detected genetic admixture in southwest China. Overall, our findings of genetic divergence within Platycarya support the hypothesis of allopatric speciation. However, episodes of population interconnection were identified, at least in southwest China, suggesting that the genus has had a dynamic population history. 相似文献
992.
Jesenia Acurio Kurt Herlitz Felipe Troncoso Claudio Aguayo Patricio Bertoglia Carlos Escudero 《Purinergic signalling》2017,13(1):51-60
We aim to investigate whether A2A/nitric oxide-mediated regulation of vascular endothelial growth factor (VEGF) expression is impaired in feto-placental endothelial cells from late-onset pre-eclampsia. Cultures of human umbilical vein endothelial cells (HUVECs) and human placental microvascular endothelial cells (hPMECs) from normal and pre-eclamptic pregnancies were used. Assays by using small interference RNA (siRNA) for A2A were performed, and transfected cells were used for estimation of messenger RNA (mRNA) levels of VEGF, as well as for cell proliferation and angiogenesis in vitro. CGS-21680 (A2A agonist, 24 h) increases HUVEC and hPMEC proliferation in a dose response manner. Furthermore, similar to CGS-21680, the nitric oxide donor, S-nitroso-N-acetyl-penicillamine oxide (SNAP), increased cell proliferation in a dose response manner (logEC50 10?9.2 M). In hPMEC, CGS-21680 increased VEGF protein levels in both normal (~1.5-fold) and pre-eclamptic pregnancies (~1.2-fold), an effect blocked by the A2A antagonist, ZM-241385 (10?5 M) and the inhibitor of NO synthase, N ω-nitro-L-arginine methyl ester hydrochloride (L-NAME). Subsequently, SNAP partially recovered cell proliferation and in vitro angiogenesis capacity of cells from normal pregnancies exposed to siRNA for A2A. CGS-21680 also increased (~1.5-fold) the level of VEGF mRNA in HUVEC from normal pregnancies, but not in pre-eclampsia. Additionally, transfection with siRNA for A2A decrease (~30 %) the level of mRNA for VEGF in normal pregnancy compared to untransfected cells, an effect partially reversed by co-incubation with SNAP. The A2A-NO-VEGF pathway is present in endothelium from microcirculation and macrocirculation in both normal and pre-eclamptic pregnancies. However, NO signaling pathway seems to be impaired in HUVEC from pre-eclampsia. 相似文献
993.
994.
Korey J. Brownstein Mahmoud Gargouri William R. Folk David R. Gang 《Metabolomics : Official journal of the Metabolomic Society》2017,13(11):133
Introduction
Botanicals containing iridoid and phenylethanoid/phenylpropanoid glycosides are used worldwide for the treatment of inflammatory musculoskeletal conditions that are primary causes of human years lived with disability, such as arthritis and lower back pain.Objectives
We report the analysis of candidate anti-inflammatory metabolites of several endemic Scrophularia species and Verbascum thapsus used medicinally by peoples of North America.Methods
Leaves, stems, and roots were analyzed by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) and partial least squares-discriminant analysis (PLS-DA) was performed in MetaboAnalyst 3.0 after processing the datasets in Progenesis QI.Results
Comparison of the datasets revealed significant and differential accumulation of iridoid and phenylethanoid/phenylpropanoid glycosides in the tissues of the endemic Scrophularia species and Verbascum thapsus.Conclusions
Our investigation identified several species of pharmacological interest as good sources for harpagoside and other important anti-inflammatory metabolites.995.
Caroline Sharmilee Josefin Karlsson Sofiia Miliutenko Anna Björklund Ulla Mörtberg Bo Olofsson Susanna Toller 《The International Journal of Life Cycle Assessment》2017,22(8):1302-1317
Purpose
The purpose of the study was to outline and demonstrate a new geographic information system (GIS)-based approach for utilising spatial geological data in three dimensions (i.e. length, width and depth) to improve estimates on earthworks during early stages of road infrastructure planning.Methods
This was undertaken by using three main methodological steps: mass balance calculation, life cycle inventory analysis and spatial mapping of greenhouse gas (GHG) emissions and energy use. The mass balance calculation was undertaken in a GIS environment using two assumptions of geological stratigraphy for two proposed alternative road corridors in Sweden. The estimated volumes of excavated soil, blasted rock and filling material were later multiplied with the GHG emission and energy use factors for these processes, to create spatial data and maps in order to show potential impacts of the studied road corridors. The proposed GIS-based approach was evaluated by comparing with actual values received after one alternative was constructed.Results and discussion
The results showed that the estimate of filling material was the most accurate (about 9 % deviation from actual values), while the estimate for excavated soil and blasted rock resulted in about 38 and 80 % deviation, respectively, from the actual values. It was also found that the total volume of excavated and ripped soils did not change when accounting for stratigraphy.Conclusions
The conclusion of this study was that more information regarding embankment height and actual soil thickness would further improve the model, but the proposed GIS-based approach shows promising results for usage in LCA at an early stage of road infrastructure planning. Thus, by providing better data quality, GIS in combination with LCA can enable planning for a more sustainable transport infrastructure.996.
Nur Syafiqah Abdul Ghani Roghayeh Abedi Karjiban Mahiran Basri Nur Hana Faujan Wui Zhuan Lim 《International journal of peptide research and therapeutics》2017,23(3):393-407
Alzheimer’s disease (AD) is a neurodegenerative disorder caused by overproduction and accumulation of amyloid beta-peptide (Aβ). The hallmarks associated with this AD are the presence of Aβ plaques between the nerve cell in the brain which leading to synaptic loss in memory. The amyloid plaques contain of transition metals like zinc, copper and iron. In a healthy brain, the metal ions are present in balance concentration. High concentrations of Zn are normally released during neurotransmission process. The release of Zn might cause the aggregation of Aβ leading to AD. Amyloid-β1–42 is the main type of Aβ in amyloid plaque. There still have limited explanation on how Aβ1–42 interaction with Zn metal, as well as the effect of Zn metal on the Aβ structure in different solvents in atomic detail. Therefore, we investigated the structural changes of Aβ1–42 in water (Aβ-H2O) and the mixed hexafluoroisopropanol (HFIP) with water (Aβ-HFIP/H2O). The mixed solvent consisted of hexafluoroisopropanol (HFIP) and water was used with the ratio of HFIP:H2O (80:20). The effect of zinc ion was also examined for the interaction of Aβ peptide with zinc in water (Aβ-Zn-H2O) and mixed solvent (Aβ-Zn-HFIP/H2O) using all atom level molecular dynamics (MD) calculations for 1 μs. We found that Aβ-Zn-HFIP/H2O contained more α-helix compared to Aβ-HFIP/H2O while Aβ-H2O and Aβ-Zn-H2O produced well-dissolved structure and they contained more β-sheets. β-turns are possible to bind with the receptor proteins and may induce the aggregation process in AD. Thus, Aβ-H2O and Aβ-Zn-H2O have higher possibility leading to AD compared to Aβ-Zn-HFIP/H2O and Aβ-HFIP/H2O models. 相似文献
997.
998.
Elif Erdem Meltem Yagmur Hazal Boral Macit Ilkit Reha Ersoz Seyedmojtaba Seyedmousavi 《Mycopathologia》2017,182(3-4):379-385
We investigated the clinical and mycological characteristics of four cases of mycotic keratitis caused by Aspergillus flavus that occurred from July 2014 to May 2015 at Çukurova University Hospital, Adana, Turkey. In a 10-month period, a total of 64 corneal smear/scrapings were examined from patients with suspected mycotic keratitis. Fungal cultures were positive in six of these patients, indicating a 9.4% incidence of mycotic keratitis in this region, including four cases of A. flavus and two cases of Fusarium spp. The predisposing factors, clinical presentation, and success of the therapeutic approaches were further evaluated. For all cases, topical voriconazole was the first choice of treatment. Surgical procedures were required to control infection in 3 of the 4 cases, including intrastromal voriconazole injection for two cases and keratoplasty for one case. Predisposing factors included trauma (two cases, 50%), contact lens use (one case, 25%), and previous ocular surgery (one case, 25%). The clinical presentations also differed, including a well-limited ulcer (one case), an ulcer with an irregular feathery margin (one case), and ulcers with satellite lesions (two cases). The mean duration between the time of presentation and definitive diagnosis by culture was 14 days (8–25 days). We observed that A. flavus keratitis can present with different underlying factors and clinical conditions. A combination of antifungal therapy and supportive surgical intervention may resolve infections caused by A. flavus in the cornea. 相似文献
999.
Huilin Su Li Li Benlin Cheng Junhao Zhu Qiangqiang Zhang Jinhua Xu Min Zhu 《Mycopathologia》2017,182(5-6):549-554
Infections caused by Trichophyton rubrum are very common in dermatological disease. It most often appears as superficial cutaneous mycosis, such as tinea manuum, tinea pedis, and tinea corporis. However, deep infection caused by T. rubrum was rarely reported. We describe a case of mixed type of deep infection caused by T. rubrum in a 45-year-old man with no significant immunodeficiency. This patient had a history of onychomycosis on the toenails without regular treatment for nearly 6 years. And, he had erythema, papule, and nodules on the submandibular area, neck, and chest for almost 1 year. After treated with intravenous infusion of cefotiam for 2 weeks, the lesion aggravated. The fungal direct microscopic examination of pyogenic fluid was positive, and the fungal cultures that produced reddish-brown and yellow pigment showed cottony, wooly, and white colony. After the DNA sequencing, it was identified as T. rubrum. We gave the patient oral terbinafine 250 mg per day and bifonazole cream for external use. Six months later, the patient’s skin lesion was disappeared, and healthy nail growth was seen in two-thirds of nail bed. The terbinafine is effective against deep infection caused by T. rubrum. 相似文献
1000.
Tobias Lahmer Clarissa Prazeres da Costa Jürgen Held Sebastian Rasch Ursula Ehmer Roland M. Schmid Wolfgang Huber 《Mycopathologia》2017,182(7-8):701-708