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31.
Mansour MA Mostafa AM Nagi MN Khattab MM Al-Shabanah OA 《Comparative biochemistry and physiology. Toxicology & pharmacology : CBP》2002,132(2):123-128
The effect of aminoguanidine (AG) on nephrotoxicity induced by cisplatin (CDDP) was investigated. A single dose of CDDP (7.5 mg/kg i.p.) induced nephrotoxicity, manifested biochemically by a significant elevation in serum urea, creatinine and a severe decrease in serum albumin. Moreover, marked increases in kidney weight, urine volume and urinary excretion of albumin were observed. Nephrotoxicity was further confirmed by a significant decrease in glutathione-S-transferase (GST, E.C. 2.5.1.18), glutathione peroxidase (GSH-Px, E.C. 1.11.1.9) and catalase (E.C. 1.11.1.6) and a significant increase in lipid peroxides measured as malondialdhyde (MDA) in kidney homogenates. Administration of AG (100 mg/kg per day p.o.) in drinking water 5 days before and 5 days after CDDP injection produced a significant protection against nephrotoxicity induced by CDDP. The amelioration of nephrotoxicity was evidenced by significant reductions in serum urea and creatinine concentrations. In addition, AG tended to normalize decreased levels of serum albumin. Urine volume, urinary excretions of albumin and GST and kidney weight were significantly decreased. Moreover, AG prevented the rise of MDA and the reduction of GST and GSH-Px activities in the kidney. These results suggest that AG has a protective effect on nephrotoxicity induced by CDDP and it may therefore improve the therapeutic index of CDDP. 相似文献
32.
Abdel-Rahman AA Abdel-Megied AE Goda AE Zeid IF El Ashry el SH 《Nucleosides, nucleotides & nucleic acids》2003,22(11):2027-2038
Reverse nucleoside derivatives of 2-(methylsulfanyl)uracils 6a-d were prepared by treating of the sodium salt of 2-(methylsulfanyl)uracils (5a-d) with methyl 2,3-O-isopropylidene-5-O-p-toluenesulfonyl-beta-D-ribofuranoside (2). The alkylation of 2-thiouracils 4a-d with methyl 5-deoxy-5-iodo-2,3-O-isopropylidene-D-ribofuranoside (3) afforded the corresponding S-ribofuranoside derivatives 8a-d. Deisopropylidenation of 6a-d and 8a-d afforded the corresponding deprotected derivatives 7a-d and 9a-d, respectively. The Anti-HBV activity of selected compounds was studied. 相似文献
33.
Breslin MJ Duggan ME Halczenko W Fernandez-Metzler C Hunt CA Leu CT Merkle KM Naylor-Olsen AM Prueksaritanont T Stump G Wallace A Rodan SB Hutchinson JH 《Bioorganic & medicinal chemistry letters》2003,13(10):1809-1812
Two novel series of small-molecule RGD mimetics containing either a substituted pyridone or pyrazinone central constraint were prepared. Modification of the beta-alanine 3-substituent produced compounds that are potent and selective alpha(v)beta(3) antagonists and exhibit a range of physicochemical properties. 相似文献
34.
Fungi belonging to the genus Coelomomyces can infect mosquito larvae and develop within the larval hemocoel. To examine fungal development, Aedesaegypti larvae infected with Coelomomyces stegomyiae Keilin were fixed, embedded and sectioned for both light and electron microscopy. While fungal hyphae of C. stegomyiae did not invade cells other than the cuticular epithelial cells, they did penetrate a number of tissues including muscles,
midgut, hemopoietic organ, imaginal discs, and Malpighian tubules.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
35.
Lung epithelial barrier function and wound healing are decreased by IL-4 and IL-13 and enhanced by IFN-gamma 总被引:3,自引:0,他引:3
Ahdieh Minoo; Vandenbos Tim; Youakim Adel 《American journal of physiology. Cell physiology》2001,281(6):C2029
To understand theeffects of cytokines on epithelial cells in asthma, we haveinvestigated the effects of interleukin (IL)-4, IL-13, and interferon(IFN)- on barrier function and wound healing in Calu-3 human lungepithelial cells. IL-4 and IL-13 treatment of Calu-3 cells grown onTranswell filters resulted in a 70-75% decrease in barrierfunction as assessed by electrophysiological and[14C]mannitol flux measurements. In contrast, IFN-enhanced barrier function threefold using these same parameters. Cellstreated concurrently with IFN- and IL-4 or IL-13 showed an initialdecline in barrier function that was reversed within 2 days, resulting in barrier levels comparable to control cells. Analysis of the tightjunction-associated proteins ZO-1 and occludin showed that IL-4 andIL-13 significantly reduced ZO-1 expression and modestly decreasedoccludin expression compared with controls. IFN-, quite unexpectedlygiven its enhancing effect on barrier function, reduced expression ofZO-1 and occludin to almost undetectable levels compared with controls.In wound-healing assays of cells grown on collagen I, IL-4 and IL-13decreased migration, whereas IFN- treatment enhanced migration,compared with control cells. Addition of IFN-, in combination withIL-4 or IL-13, restored migration of cells to control levels. Migrationdifferences observed between the various cytokine treatments wascorrelated with expression of the collagen I-binding21-integrin at the leading edge of cellsat the wound front; 21-integrinexpression was decreased in IFN--treated cells compared withcontrols, whereas it was highest in IL-4- and IL-13-treated cells.These results demonstrate that IL-4 and IL-13 diminish the capacity ofCalu-3 cells to maintain barrier function and repair wounds, whereasIFN- promotes epithelial restitution by enhancing barrier functionand wound healing. 相似文献
36.
Development and organization of polarity-specific segregation of primary vestibular afferent fibers in mice 总被引:1,自引:0,他引:1
A striking feature of vestibular hair cells is the polarized arrangement of their stereocilia as the basis for their directional
sensitivity. In mammals, each of the vestibular end organs is characterized by a distinct distribution of these polarized
cells. We utilized the technique of post-fixation transganglionic neuronal tracing with fluorescent lipid soluble dyes in
embryonic and postnatal mice to investigate whether these polarity characteristics correlate with the pattern of connections
between the endorgans and their central targets; the vestibular nuclei and cerebellum. We found that the cerebellar and brainstem
projections develop independently from each other and have a non-overlapping distribution of neurons and afferents from E11.5
on. In addition, we show that the vestibular fibers projecting to the cerebellum originate preferentially from the lateral
half of the utricular macula and the medial half of the saccular macula. In contrast, the brainstem vestibular afferents originate
primarily from the medial half of the utricular macula and the lateral half of the saccular macula. This indicates that the
line of hair cell polarity reversal within the striola region segregates almost mutually exclusive central projections. A
possible interpretation of this feature is that this macular organization provides an inhibitory side-loop through the cerebellum
to produce synergistic tuning effects in the vestibular nuclei. The canal cristae project to the brainstem vestibular nuclei
and cerebellum, but the projection to the vestibulocerebellum originates preferentially from the superior half of each of
the cristae. The reason for this pattern is not clear, but it may compensate for unequal activation of crista hair cells or
may be an evolutionary atavism reflecting a different polarity organization in ancestral vertebrate ears. 相似文献
37.
38.
Marit Espe Raja Mansingh Rathore Zhen-Yu Du Bjørn Liaset Adel El-Mowafi 《Amino acids》2010,39(2):449-460
The current experiment aimed to study whether interactions with lipid metabolism possibly might explain the relative increased
liver weight obtained in fish fed sub-optimal methionine levels. A basal diet based on a blend of plant proteins which is
low in methionine (1.6 g Met/16 g N) was compared to a methionine adequate diet (2.2 g Met/16 g N) prepared by adding dl-methionine (2.4 g/kg) to the basal diet in the expense of wheat grain. Fish oil was used as the lipid source. The diets were
balanced in all nutrients except methionine. The diets were fed to Atlantic salmon (500 g BW) for a period of 3 months. Feed
intake did not differ, rendering the intake of all nutrients except methionine equal. Fish fed the low methionine diet had
an increased liver size relative to body weight, indicating fat deposition in the liver. Fish given the sub-optimal methionine
diet showed about six times higher fatty acid synthase (FAS) activity as compared to the fish fed the adequate methionine
diet, indicating a higher de novo lipogenesis. A significant rise in the liver 18:1 to 18:0 fatty acid ratios also supported
storage of lipids over fatty acid oxidation. Indeed, methionine limitation resulted in significantly higher TAG concentrations
in the liver. Sub-optimal dietary methionine also resulted in lower hepatic taurine concentrations and the total bile acids
concentrations were reduced in faeces and tended to be reduced in plasma. Taken together, our data show that salmon fed sub-optimal
methionine levels had increased relative liver weight and developed signs commonly described in the early stage of non-alcoholic
fatty liver disease in rodent models (increased FAS activity, changed fatty acid ratios and TAG accumulation). 相似文献
39.
40.
Samia Dabbou Imed Rjiba Adel Echbili Noureddine Gazzah Beligh Mechri Mohamed Hammami 《化学与生物多样性》2010,7(7):1801-1813
Our study reports the triglyceride (triacylglycerol, TAG) composition of five new Tunisian virgin olive oil cultivars obtained through controlled crossings of the cultivar (cv.) Chemlali Sfax. These cultivars have been selected among a progeny of 500 olive descendants, based on an evaluation of the fatty‐acid (FA) composition of their oils. Among these samples, two were derived from the crossing with the cv. Sigoise as pollinator (SM634) or pollen acceptor (SM1110) and the others from the crossing with the cv. Meski as pollen acceptor (SM513, SM514, and SM517). The five descendants were characterized by a good fat value, a balanced FA composition, and a high content of triolein, varying between 26.9 (SM514) and 45.46% (SM1110). They had an improved FA composition as compared to that of the cv. Chemlali Sfax and their fruits were slightly bigger. The principal component analysis suggested that the TAG variables were more suitable than the total FAs for an optimum classification of the cultivar samples analyzed. The cultivars obtained through the crossing with the cv. Sigoise (as pollen acceptor or pollinator) had a more favorable composition of FAs and TAG than those obtained through the crossing with the cv. Meski, which indicated that genetic factors had the most important influence on the quality of the virgin olive oils. 相似文献