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81.
A series of unsymmetrically disubstituted urea derivatives 128 has been synthesized and screened for their antiglycation activity in vitro. Compounds 26 (IC50 = 4.26 ± 0.25 μM), 1 (IC50 = 5.8 ± 0.08 μM), 22 (IC50 = 4.26 ± 0.25 μM), 6 (IC50 = 6.4 ± 0.02 μM), 5 (IC50 = 6.6 ± 0.26 μM), 2 (IC50 = 7.02 ± 0.31 μM), 3 (IC50 = 7.14 ± 0.84 μM), 27 (IC50 = 7.27 ± 0.36 μM), 4 (IC50 = 8.16 ± 1.04 μM), 21 (IC50 = 8.4 ± 0.15 μM), 23 (IC50 = 9.0 ± 0.35 μM) and 13 (IC50 = 15.22 ± 6.7 μM) showed an excellent antiglycation activity far better than the standard (rutin, IC50 = 41.9 ± 2.3 μM). This study thus provides a series of potential molecules for further studies of antiglycation agents.  相似文献   
82.
One group of commonly found parasites in birds, for which fitness consequences and effects on life history traits have been much debated are Haemosporidian blood parasites. In a long term study population of great reed warblers Acrocephalus arundinaceus in Sweden, previous studies have shown that the Haemosporidian blood parasites are in their chronic phase during the breeding season and that the fitness of infected and non‐infected birds are similar. In the present study, we quantified parasite intensity (parasitemia) in 718 adults great reed warblers sampled between 1987 and 1998 for the three most common parasite species; Haemoproteus payevskyi (lineage GRW1), Plasmodium ashfordi (GRW2) and Plasmodium relictum (GRW4). We verified that the q‐PCR method is accurately quantifying Haemoproteus payevskyi (GRW1) as it was highly correlated with the number of parasites seen under microscope. Frequency of mixed infections with two lineages was significantly higher than expected based on the prevalence of each of the three parasite lineages. The mean level of parasitemia was significantly different for the three lineages and individual birds had repeatable parasitemia levels between years. Females tended to have a higher parasitemia than males for all three parasite lineages combined. Females with higher GRW1 parasitemia tended to arrive later in spring to their breeding sites. There was a negative correlation between parasitemia and number of fledged offspring for GRW1, and a tendency for a negative correlation between GRW2 parasitemia and the proportion of recruiting offspring. Overall our results demonstrate that chronic Haemosporidian infections can have slight but significant effects on host life history traits, and therefore may act as important selective agents in wild bird populations.  相似文献   
83.

Background

Base deficit (BD) is commonly used in the operating room (OR) as an endpoint of resuscitation. BD is used as a surrogate marker for the accumulation of lactic acid(Lac). However, the BD can be affected by large amounts of saline.

Methods

We conducted a survey of anesthesiologists regarding the use of BD. We also studied the reliability of BD to determine the presence of hyperlactatemia (HL). Patients undergoing general anesthesia were eligible for enrollment if they were receiving an arterial line as part of their routine care. If an arterial blood gas was drawn by the operative team as part of the routine care, the remainder of the unused blood was also used to measure Lac.

Results

Survey: 73 staff anesthesiologists were surveyed. Over 70% of respondents used BD as an endpoint of resuscitation. Base Deficit Study: 35 patients were enrolled resulting in 88 arterial blood gases with corresponding Lac. Mean age was 61.4 ± 14.3 years, 43% were male. Mean pH was 7.39 ± 0.05, the mean bicarbonate was 23.0 ± 2.3 meq/L, the mean BD 1.34 ± 2.3, and the mean Lac was 1.58 ± 0.71 mmol/L. Mean ASA risk score was 3.16 ± 0.71. ROC area under the curve for base deficit to detect HL was 0.58.

Conclusion

BD can often mislead the clinician as to the actual Lac. Lac can now be measured in the OR in real time. Therefore, if clinicians in the operative setting want to know the Lac, it should be measured directly.  相似文献   
84.
Plant secondary metabolites have been recently used for the synthesis of different nanoparticles. The present investigation aimed at evaluating the effect of gold (AuNPs) and silver (AgNPs) nanoparticles synthesized using Acalypha fruticosa leaf extracts to control the mosquito Culex pipiens. The A. fruticosa AuNPs and AgNPs spectra displayed their maximum absorption at 550 nm and 440 nm, respectively. The infrared spectra revealed different functional groups related to different chemical compounds. The larval mortality of aqueous leaf extract of A. fruticosa was 499.54 ppm (LC50) and 1734.06 ppm (LC90) after 24 h of treatment. This study revealed that AuNP (LC50, 30.2 and LC90, 104.83 ppm) and AgNP (LC50, 52.86 and LC90, 157.227 ppm) preparations were highly effective compared to the A. fruticosa extract alone and also more affordable, as a smaller amount was required. The present findings show the potential larvicidal effect of the synthesized AuNPs and AgNPs for the control of mosquito-mediated disease transmission.  相似文献   
85.
Molecular Biology Reports - A recent spike in demand for chemical preservative free food has derived the scientific community to develop natural ways of food preservation. Therefore,...  相似文献   
86.
Wang  Xinghe  Muhammad  Ishfaq  Sun  Xiaoqi  Han  Meiyu  Hamid  Sattar  Zhang  Xiuying 《Molecular biology reports》2018,45(5):881-891

It is well documented that liver is the primary target organ of aflatoxin B1 (AFB1) and curcumin proved to be effective against AFB1-induced liver injury. In the present study, we investigated the preventive effects of curcumin against AFB1-induced apoptosis through the molecular regulation of p53, caspase-3, Bax, caspase-9, Bcl-2 and cytochrome-C associated with mitochondrial pathway. Liver antioxidant levels were measured. The hallmarks of apoptosis were analysed by methyl green-pyronin-Y staining, transmission electron microscopy, RT-PCR and western blot. Results revealed that dietary curcumin ameliorated AFB1-induced oxidative stress in a dose-dependent manner. Methyl green-pyronin-Y staining and transmission electron microscopy showed that AFB1 induced apoptosis and caused abnormal changes in liver cells morphology such as condensation of chromatin material, reduces cell volume and damaged mitochondria. Moreover, mRNA and protein expression results manifested that apoptosis associated genes showed up-regulation in AFB1 fed group. However, the supplementation of dietary curcumin (dose-dependently) alleviated the increased expression of the apoptosis associated genes at mRNA and protein level, and restored the hepatocytes normal morphology. The study provides an insight and a better understanding of the preventive mechanism of curcumin against AFB1-induced apoptosis in hepatocytes and provide scientific basis for the therapeutic uses of curcumin.

  相似文献   
87.
A rapid, selective and sensitive high performance liquid chromatography–tandem mass spectrometry method (LC–MS/MS) was developed and validated for the determination and pharmacokinetic investigation of cefuroxime in human plasma. Cefuroxime and the internal standard (IS), cefoxitin, were extracted from plasma samples using solid phase extraction with Oasis HLB cartridges. Chromatographic separation was performed on a LiChrospher® 60 RP Select B column (125 mm × 4 mm i.d., 5 μm particle size) using acetonitrile:5 ± 0.2 mM ammonium acetate solution:glacial acetic acid (70:30:0.020, v/v/v) as the mobile phase at a flow rate of 0.8 mL/min. Detection of cefuroxime and cefoxitin was achieved by tandem mass spectrometry with an electrospray ionization (ESI) interface in negative ion mode. The calibration curves were linear over the range of 81.0–15976.2 ng/mL with the lower limit of quantitation validated at 81.0 ng/mL. The intra- and inter-day precisions were within 7.6%, while the accuracy was within ±6.3% of nominal values. No matrix effect was observed in this method. The validated LC–MS/MS method was successfully applied for the evaluation of pharmacokinetic and bioequivalence parameters of cefuroxime after an oral administration of 500 mg cefuroxime tablet to 36 healthy male volunteers.  相似文献   
88.
The online photoreaction of the rose bengal photosensitized luminol–copper (II) chemiluminescence (CL) system was used for the determination of β-nicotinamide adenine dinucleotide (NADH) and ethanol (EtOH) in pharmaceutical formulations combined with a flow injection technique. NADH can significantly enhance the CL emission of the reaction. For EtOH, alcohol dehydrogenase in soluble form was utilized in the presence of nicotinamide adenine dinucleotide resulting in NADH production. The limit of detection (3σ blank, 𝑛 = 3) of 4.0 × 10−8 and 2.17 × 10−5 M, and linear range 1.3 × 10−7 to 2.5 × 10−5 M (R2 = 0.9998, n = 6) and 0.11–2.17 × 10−3 M (R2 = 0.9996, n = 6) were obtained for NADH and EtOH respectively. The injection rate was 100 h−1 with a relative standard deviation (n = 3) of 1.5–4.8% in the range studied for both analytes. The procedure was satisfactorily applied to pharmaceutical formulations with recoveries in the range 91.6 ± 3.0% to 110 ± 2.0% for NADH and 88 ± 3.0% to 95.4 ± 4.0% for EtOH. The results obtained were very consistent and did not differ considerably from the reported approaches at a 95% confidence limit. The possible mechanism of the CL reaction is also explained briefly.  相似文献   
89.
A quick, simple, and reliable method for the extraction of DNA from grapevine species, hybrids, andAmpelopsis brevipedunculata (Vitaceae) has been developed. This method, based on that of Doyle and Doyle (1990), is a CTBA-based extraction procedure modified by the use of NaCl to remove polysaccharides and PVP to eliminate polyphenols during DNA purification. The method has also been used successfully for extraction of total DNA from other fruit species such as apple (Malus domestica), apricot (Prunus armeniaca), cherry (Prunus avium), peach (Prunus persica), plum (Prunus domestica), and raspberry (Rubus idaeus). DNA yield from this procedure is high (up to 1 mg/g of leaf tissue). DNA is completely digestible with restriction endonucleases and amplifiable in the polymerase chain reaction (PCR), indicating freedom from common contaminating compounds.  相似文献   
90.
We studied a sample of 75 Chinese, 73 Malay, and 29 Indian healthy neonates taking part in a cohort study to examine potential differences in neonatal brain morphology and white matter microstructure as a function of ethnicity using both structural T2-weighted magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). We first examined the differences in global size and morphology of the brain among the three groups. We then constructed the T2-weighted MRI and DTI atlases and employed voxel-based analysis to investigate ethnic differences in morphological shape of the brain from the T2-weighted MRI, and white matter microstructure measured by fractional anisotropy derived from DTI. Compared with Malay neonates, the brains of Indian neonates’ tended to be more elongated in anterior and posterior axis relative to the superior-inferior axis of the brain even though the total brain volume was similar among the three groups. Although most anatomical regions of the brain were similar among Chinese, Malay, and Indian neonates, there were anatomical variations in the spinal-cerebellar and cortical-striatal-thalamic neural circuits among the three populations. The population-related brain regions highlighted in our study are key anatomical substrates associated with sensorimotor functions.  相似文献   
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