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181.
Albert A. Smith 《Journal of biomolecular NMR》2017,67(2):77-94
Software for fitting of NMR spectra in MATLAB is presented. Spectra are fitted in the frequency domain, using Fourier transformed lineshapes, which are derived using the experimental acquisition and processing parameters. This yields more accurate fits compared to common fitting methods that use Lorentzian or Gaussian functions. Furthermore, a very time-efficient algorithm for calculating and fitting spectra has been developed. The software also performs initial peak picking, followed by subsequent fitting and refinement of the peak list, by iteratively adding and removing peaks to improve the overall fit. Estimation of error on fitting parameters is performed using a Monte-Carlo approach. Many fitting options allow the software to be flexible enough for a wide array of applications, while still being straightforward to set up with minimal user input. 相似文献
182.
183.
Zafar Iqbal Khan Kafeel Ahmad Muhammad Ashraf Rukhsana Parveen Zahara Bibi Irfan Mustafa 《人类与生态风险评估》2016,22(1):86-98
The present research was conducted in district Jhang, Pakistan, to evaluate the concentration of metals/metalloids in soil and pumpkin (Cucurbita maxima) irrigated with domestic wastewater. Data revealed that the levels of metals and metalloids in soil samples from two different sites were below the safe limits except Cd, whereas, in the vegetable, the concentrations of As, Se, Ni, Mo, Pb, Mn, and Cu were above the safe limits. The levels of 12 metals and metalloids in the soil were ranged between 0.14 to 22.76 mg/kg at site-I and 0.16 to 22.13 mg/kg at site-II. The levels of these metals in the vegetable were found 0.35 to 61.13 mg/kg at site-I and 0.31 to 53.63 mg/kg at site-II. The transfer factor at both sites was highest for As and Co. The pollution load index recorded for Se, Cu, Cd, Mo, Pb, and Co was greater than 1. The daily intake of As, Mn, and Mo was above the oral reference dose, which reflects that the intake of pumpkin is not safe for the inhabitants of the selected sites. The control measures should be taken to phytoextract heavy metals and metalloids from polluted sites so as to reduce the health risks. 相似文献
184.
185.
A patent foramen ovale is a common intracardiac finding that is located between the left and right atrium. It can cause right-to-left shunting and has a high prevalence in patients who suffer a cryptogenic stroke. Earlier trials did not show superiority of percutaneous patent foramen ovale closure with standard medical therapy over standard medical therapy alone in the treatment of cryptogenic stroke. Interestingly, several meta-analyses show positive results regarding closure, suggesting underpowering of the individual trials. Recently, two large prospective trials and one long-term follow-up study showed benefit of percutaneous closure over standard medical therapy in treatment of cryptogenic stroke. A larger right-to-left shunt or the presence of an atrial septal aneurysm were predictors for a recurrent event. Therefore, percutaneous patent foramen ovale closure after cryptogenic stroke should be recommended over antiplatelet therapy alone in patients younger than 55 years of age with a high-risk patent foramen ovale. 相似文献
186.
Lead is a heavy metal widely distributed in the environment. Lead is a ubiquitous environmental toxin that is capable of causing numerous acute and chronic illnesses. Human and animal exposure demonstrates that lead is nephrotoxic. However, attempts to reduce lead-induced nephrotoxicity were not found suitable for clinical use. Recently, flaxseed oil (FXO), a rich source of ω-3 fatty acids and lignans, has been shown to prevent/reduce the progression of certain types of cardiovascular and renal disorders. In view of this, the present study investigates the protective effect of FXO on lead acetate (PbAc)-induced renal damage. Rats were pre-fed normal diet and the diet rich in FXO for 14 days, and then, four doses of lead acetate (25 mg/kg body weight) were administered intraperitoneally while still on diet. Various serum parameters, enzymes of carbohydrate metabolism, brush border membrane (BBM), and oxidative stress were analyzed in rat kidney. PbAc nephrotoxicity was characterized by increased serum creatinine and blood urea nitrogen. PbAc increased the activities of lactate dehydrogenase and NADP-malic enzyme, whereas it decreased malate and glucose-6-phosphate dehydrogenase, glucose-6-phosphatase, fructose-1, 6-bisphosphatase, and BBM enzyme activities. PbAc caused oxidant/antioxidant imbalances as reflected by increased lipid peroxidation and decreased activities of superoxide dismutase, glutathione peroxidase, and catalase. In contrast, FXO alone enhanced the enzyme activities of carbohydrate metabolism, BBM, and antioxidant defense system. FXO feeding to PbAc-treated rats markedly enhanced resistance to PbAc-elicited deleterious effects. In conclusion, dietary FXO supplementation ameliorated PbAc-induced specific metabolic alterations and oxidative damage by empowering antioxidant defense mechanism and improving BBM integrity and energy metabolism. 相似文献
187.
188.
The recovery of Lactobacillus bulgaricus was studied in correlation to the kinetics of cell drying. When bacteria were dehydrated at 30 °C, either in the presence
or the absence of sucrose, the drying kinetics corresponds to a Fickean diffusion in correspondence with a short lag time.
In contrast, when the bacteria were dehydrated at 70 °C in the absence of sugar, the kinetics corresponds to an anomalous
diffusion, and the lag time is four to five times higher than that at 30 °C. However, when drying at 70 °C was carried out
in the presence of sucrose, drying kinetics turned into a Fickean process parallel to a substantial decrease in the lag time.
The pattern of water desorption was correlated with the critical water activity. When the drying kinetics corresponds to a
Fickean diffusion, the lag time started to increase at 0.7 water activity, but when the cells were dried at 70 °C, the damage
started at 0.5 water activity. This observation indicates that the drying rate affects the pattern of water desorption, and
it can change the value of critical water activity. These results put into relevance that the cell recovery is due to the
drying history and that the recovery increase produced by sucrose can be related to the maintenance of kinetic barriers for
water desorption. 相似文献
189.
In several vascular inflammatory reactions (i.e. immunity and thrombosis) inflammatory mediators lead to the activation of vascular endothelial cells (EC). To date, a number
of functional molecules induced on the surface of activated-EC have been identified. We report here that Globotetraosylceramide
(Gb4), a glycosphingolipid expressed in EC, is a novel inducible molecule on EC activated by TNF-α. The cell surface expression
of Gb4 is increased in a time-dependent manner under TNF-α stimulation, which shows distinct expression kinetics of major
proteins induced by TNF-α on EC. MALDI-TOF-MS analysis revealed that the enhanced Gb4 predominantly contains C24:0 fatty acid
in the ceramide moiety. Isolated caveolae/lipid raft-enriched detergent insoluble membrane domains in activated-EC predominantly
contain this molecular species of Gb4. Gb4 containing C16:0 fatty acid in the ceramide moiety, which is known to constitute
the major species of Gb4 in plasma, is also found as a major molecular species in EC. These observations indicate that Gb4,
especially with very long fatty acid, is enhanced in EC during its inflammatory reaction, and suggest the potential utility
of Gb4 as a biomarker for monitoring inflammation status of EC involving its related diseases. 相似文献
190.
Aileen F. G. Bongat Rina Saksena Roberto Adamo Yukari Fujimoto Zenyu Shiokawa Dwight C. Peterson Koichi Fukase Willie F. Vann Pavol Kováč 《Glycoconjugate journal》2010,27(1):69-77
Using recombinant tetanus toxin HC fragment (rTT-HC) as carrier, we prepared multimeric bivalent immunogens featuring the synthetic hexasaccharide fragment of O-PS of Vibrio cholerae O:1, serotype Ogawa, in combination with either the synthetic hexasaccharide fragment of O-PS of Vibrio cholerae O:1, serotype Inaba, or a synthetic disaccharide tetrapeptide peptidoglycan fragment as adjuvant. The conjugation reaction
was effected by squaric acid chemistry and monitored in virtually real time by SELDI-TOF MS. In this way, we could prepare
well-defined immunogens with predictable carbohydrate–carrier ratio, whose molecular mass and the amount of each saccharide attached could be independently determined. The ability to prepare such neoglycoconjugates opens unprecedented possibilities
for preparation of conjugate vaccines for bacterial diseases from synthetic carbohydrates. 相似文献