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1.
Antoni Pastor Magí Farré Montserrat Fitó Fernando Fernandez-Aranda Rafael de la Torre 《Journal of lipid research》2014,55(5):966-977
The analysis of peripheral endocannabinoids (ECs) is a good biomarker of the EC system. Their concentrations, from clinical studies, strongly depend on sample collection and time processing conditions taking place in clinical and laboratory settings. The analysis of 2-monoacylglycerols (MGs) (i.e., 2-arachidonoylglycerol or 2-oleoylglycerol) is a particularly challenging issue because of their ex vivo formation and chemical isomerization that occur after blood sample collection. We provide evidence that their ex vivo formation can be minimized by adding Orlistat, an enzymatic lipase inhibitor, to plasma. Taking into consideration the low cost of Orlistat, we recommend its addition to plasma collecting tubes while maintaining sample cold chain until storage. We have validated a method for the determination of the EC profile of a range of MGs and N-acylethanolamides in plasma that preserves the original isomer ratio of MGs. Nevertheless, the chemical isomerization of 2-MGs can only be avoided by an immediate processing and analysis of samples due to their instability during conservation. We believe that this new methodology can aid in the harmonization of the measurement of ECs and related compounds in clinical samples. 相似文献
2.
Bin Zhu Chongwen Yang Hongrong Liu Lingpeng Cheng Feng Song Songjun Zeng Xiaojun Huang Gang Ji Ping Zhu 《Journal of molecular biology》2014
Many double-stranded RNA (dsRNA) viruses are capable of transcribing and capping RNA within a stable icosahedral viral capsid. The turret of turreted dsRNA viruses belonging to the family Reoviridae is formed by five copies of the turret protein, which contains domains with both 7-N-methyltransferase and 2′-O-methyltransferase activities, and serves to catalyze the methylation reactions during RNA capping. Cypovirus of the family Reoviridae provides a good model system for studying the methylation reactions in dsRNA viruses. Here, we present the structure of a transcribing cypovirus to a resolution of ~ 3.8 Å by cryo-electron microscopy. The binding sites for both S-adenosyl-l-methionine and RNA in the two methyltransferases of the turret were identified. Structural analysis of the turret in complex with RNA revealed a pathway through which the RNA molecule reaches the active sites of the two methyltransferases before it is released into the cytoplasm. The pathway shows that RNA capping reactions occur in the active sites of different turret protein monomers, suggesting that RNA capping requires concerted efforts by at least three turret protein monomers. Thus, the turret structure provides novel insights into the precise mechanisms of RNA methylation. 相似文献
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Eun Jin Park Joon Young Song Min Ju Choi Ji Ho Jeon Jah-yeon Choi Tae Un Yang Kyung Wook Hong Ji Yun Noh Hee Jin Cheong Woo Joo Kim 《The Korean journal of parasitology》2014,52(4):425-428
A 45-year-old-male who had underlying ulcerative colitis and presented with fever and dry cough. Initially, the patient was considered to have invasive aspergillosis due to a positive galactomannan assay. He was treated with amphotericin B followed by voriconazole. Nevertheless, the patient deteriorated clinically and radiographically. The lung biopsy revealed eosinophilic pneumonia, and ELISA for Toxocara antigen was positive, leading to a diagnosis of pulmonary toxocariasis. After a 10-day treatment course with albendazole and adjunctive steroids, the patient recovered completely without any sequelae. Pulmonary toxocariasis may be considered in patients with subacute or chronic pneumonia unresponsive to antibiotic agents, particularly in cases with eosinophilia. 相似文献
5.
本文对我院91 ̄94年收治的35例,由淋球菌引起的急性淋菌性盆腔腹膜炎的发病情况进行了分析。资料显示:淋菌性盆腔腹膜炎发病以中青年妇女为多。性乱及不洁的性生活是诱发本病的原因。无先兆症状使本病无特异性,但脓性白带、尿路刺激症状、宫颈与阴道壁充血以及腹膜刺激症有助于本病的诊断。确诊则依据涂片染色检菌及细菌培养。大剂量的青霉素或第三代头孢菌素的应用,可使本病早日治愈。 相似文献
6.
T. Hannedouche P. Landais B. Goldfarb N. el Esper A. Fournier M. Godin D. Durand J. Chanard F. Mignon J. M. Suo et al. 《BMJ (Clinical research ed.)》1994,309(6958):833-837
OBJECTIVE--To compare the ability of angiotensin converting enzyme inhibitors and beta blockers to slow the development of end stage renal failure in non-diabetic patients with chronic renal failure. DESIGN--Open randomised multicentre trial with three year follow up. SETTING--Outpatient departments of six French hospitals. PATIENTS--100 hypertensive patients with chronic renal failure (initial serum creatinine 200-400 mumol/l. 52 randomised to enalapril and 48 to beta blockers (conventional treatment). INTERVENTIONS--Enalapril or beta blocker was combined with frusemide and, if necessary, a calcium blocker or centrally acting drug in patients whose diastolic pressure remained above 90 mm Hg. RESULTS--17 patients receiving conventional treatment and 10 receiving enalapril developed end stage renal failure. The cumulative renal survival rate was significantly better in the enalapril group than in the conventional group (P < 0.05). The slope of the reciprocal serum creatinine concentration was steeper in the conventionally treated patients (-6.89 x 10(-5)l/mumol/month) than in the enalapril group (-4.17 x 10(-5)l/mumol/month; P < 0.05). No difference in blood pressure was found between groups. CONCLUSION--In hypertensive patients with chronic renal failure enalapril slows progression towards end stage renal failure compared with beta blockers. This effect was probably not mediated through controlling blood pressure. 相似文献
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A growing body of literature has shown that stem cells are very effective for the treatment of degenerative diseases in rodents but these exciting results have not translated to clinical practice. The difference results from the divergence in genetic, metabolic, and physiological phenotypes between rodents and humans. The high degree of similarity between non-human primates(NHPs) and humans provides the most accurate models for preclinical studies of stem cell therapy. Using a NHP model to understand the following key issues, which cannot be addressed in humans or rodents, will be helpful for extending stem cell applications in the basic science and the clinic. These issues include pluripotency of primate stem cells, the safety and efficiency of stem cell therapy, and transplantation procedures of stem cells suitable for clinical translation. Here we review studies of the above issues in NHPs and current challenges of stem cell applications in both basic science and clinical therapies. We propose that the use of NHP models, in particular combining the serial production and transplantation procedures of stem cells is the most useful for preclinical studies designed to overcome these challenges. 相似文献
9.
Potential natural vegetation and pre‐anthropic pollen records on the Azores Islands in a Macaronesian context 下载免费PDF全文
This paper discusses the concept of potential natural vegetation (PNV) in the light of the pollen records available to date for the Macaronesian biogeographical region, with emphasis on the Azores Islands. The classical debate on the convenience or not of the PNV concept has been recently revived in the Canary Islands, where pollen records of pre‐anthropic vegetation seemed to strongly disagree with the existing PNV reconstructions. Contrastingly, more recent PNV model outputs from the Azores Islands show outstanding parallelisms with pre‐anthropic pollen records, at least in qualitative terms. We suggest the development of more detailed quantitative studies to compare these methodologies as an opportunity for improving the performance of both. PNV modelling may benefit by incorporating empirical data on past vegetation useful for calibration and validation purposes, whereas palynology may improve past reconstructions by minimizing interpretative biases linked to differential pollen production, dispersal and preservation. 相似文献
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