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11.
Nuwayri-Salti N Karam CN Al Jaroudi WA Usta JA Maharsy WM Bitar KM Bikhazi AB 《Canadian journal of physiology and pharmacology》2007,85(2):215-224
This project assesses the treatment role with insulin and (or) angiotensin II receptor subtype-1 (AT1-R) blocker (ARB) on insulin receptor and endothelin-1 receptor subtype (ETA-R and ETB-R) regulation in rat hearts suffering from insulin-dependent diabetes mellitus (IDDM). Animals were divided into 6 groups: groups 1, 3, and 5 were controls consisting of normal, diabetic (streptozotocin-treated, once at 0 time), and diabetic supplemented daily with insulin, respectively, whereas groups 2, 4, and 6 were the controls treated daily with losartan. One month after enrollment, rats were sacrificed and samples of cardiac tissue were snapped frozen for immunostaining and Western blotting. Insulin receptor density was observed to be upregulated in the cardiomyocytes of diabetic animals, but downregulated with insulin supplementation alone. Cotreatment with insulin and an ARB resulted in drastic increase in insulin-receptor density in the diabetic rats. In addition, expression of ETA-R in cardiomyocytes was upregulated and was consistently maintained within the various treatment modalities. However, ETB-R expression was significantly reduced in the diabetic group treated with both insulin and an ARB. The changes in the expression of the insulin, the ETA-Rs, and the ETB-Rs at the various sites of the myocardium and the effect of both insulin treatment and blockade of the AT1-R explain the new benefits related to the halting of myocardial remodeling in IDDM rats. 相似文献
12.
Three screening methods—visual scoring (V), relative conductivity (C) and fluorometry (F)—were used to study the genetic variation in cold hardiness among six populations of maritime pine (Pinus pinaster Ait.) comprising both Atlantic and Mediterranean origins. Freezing damage assessments were carried out in three organs—needles, stems and buds—in two seasons, spring and autumn. We found high levels of genetic differentiation among populations for cold hardiness in autumn, but not in spring. Within populations, differences were always significant (p?<?0.05) no matter which organ or screening method was used. Measuring F was the fastest and most easily replicated method to estimate cold hardiness and was as reliable as V and C for predicting the species performance. In autumn, there was a positive correlation between the damage measured in all three types of organs assessed, whereas in spring, correlation among organs was weak. We conclude that sampling date in spring has a crucial impact to detect genetic differences in maritime pine populations, whereas autumn sampling allows more stable comparisons. We also conclude that the fluorometry method provides a more efficient and stable comparison of cold hardiness in maritime pine. 相似文献
13.
Adnan A. Bekhit Eskedar T. Lodebo Ariaya Hymete Hanan M. Ragab Salma A. Bekhit Kikuko Amagase Afnan Batubara Mohammed A. S. Abourehab Alaa El-Din A. Bekhit Tamer M. Ibrahim 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):2320
Promising inhibitory activities of the parasite multiplication were obtained upon evaluation of in vivo antimalarial activities of new pyrazolylpyrazoline derivatives against Plasmodium berghei infected mice. Further evaluation of 5b and 6a against chloroquine-resistant strain (RKL9) of P. falciparum showed higher potency than chloroquine. In vitro antileishmanial activity testing against Leishmania aethiopica promastigote and amastigote forms indicated that 5b, 6a and 7b possessed promising activity compared to miltefosine and amphotericin B deoxycholate. Moreover, antileishmanial activity reversal of the active compounds via folic and folinic acids showed comparable results to the positive control trimethoprim, indicating an antifolate mechanism via targeting leishmanial DHFR and PTR1. The compounds were non-toxic at 125, 250 and 500 mg/kg. In addition, docking of the most active compound against putative malarial target Pf-DHFR-TS and leishmanial PTR1 rationalised the observed activities. Molecular dynamics simulations confirmed a stable and high potential binding of 7a against leishmanial PTR1. 相似文献
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15.
Embryogenic tissue of the sweet potato (Ipomoea batatas (L) LAM) genotype TIB 10 was established from in vitro axillary shoot tips on Murashige and Skoog (1962) medium supplemented with 5 M 2,4-dichlorophenoxyacetic acid. Embryogenic aggregates of fresh mass 9.0–12 mg were subjected to a rapid freezing protocol in liquid nitrogen following sucrose preculture and varying degrees of dehydration. Up to 50% of embryogenic explants survived rapid freezing after preculture on 0.4 or 0.7M sucrose only. Dehydration with silica gel to moisture contents in the range 18–41% improved the survival after cryopreservation of embryogenic tissue. Tissue dehydrated for intermediate periods exhibited poor survival. Following freezing, embryogenic tissue appeared to develop normally, retaining its competence to produce mature embryos and plantlets.Abbreviations BA
6-benzyladenine
- 2,4-D
2,4-dichlorophenoxyacetic acid
- MS
Murashige and Skoog (1962) medium 相似文献
16.
Cyclooxygenase-2 (COX-2) is overexpressed in hepatocellular carcinoma (HCC) and considered to play a role in hepatic carcinogenesis. Our aim was to examine the associations between polymorphisms in COX-2 − 765G→C and − 1195A→G and risk of HCC. We conducted a case–control study including 120 patients with HCC and 130 age- and gender-matched controls. Genotypes of the COX-2 polymorphisms − 765G→C and − 1195A→G were determined by polymerase chain reaction-based restriction fragment length polymorphism. No significant difference was observed in the genotype distribution of the − 765G→C polymorphism between patients and controls. The − 1195AA genotype was associated with an increased risk of developing HCC (OR, 2.5; 95%CI, 1.18–5.37). The A allele was present significantly more often in HCC patients (OR 1.5; 95%CI, 1.05–2.14). In conclusion, our results demonstrated that the − 1195AA genotype and A allele have an important role in HCC risk in Egyptian patients. 相似文献
17.
Homograft or allograft tissue has been available for use as replacement for diseased valves or reconstruction of major vessels for decades. However, with respect to replacement of diseased valvular tissue the search for the ideal valve still continues. In this review we will discuss the clinical indications, surgical techniques, and outcome of aortic homografts. 相似文献
18.
We report that the purified Escherichia coli OxyR protein can bind specifically upstream of the gene encoding NADH peroxidase (npr) from Enterococcus faecalis 10C1, to a site located some 144 bp from the promoter. A 34 kDa protein has been identified in crude extracts of E. faecalis that cross-reacts with polyclonal antisera to purified OxyR from E. coli and a protein(s) present in these extracts retards npr DNA fragments in gel shift assays. Taken together with the results of sequence analyses, these observations suggest that enterococcal npr is regulated by OxyR. 相似文献
19.
Al Bourgol Samy Ninotta Sandrine Garcin Thibaud Cognasse Fabrice Trone Marie-Caroline Forest Fabien Thuret Gilles Gain Philippe 《Cell and tissue banking》2021,22(3):479-486
Cell and Tissue Banking - The detection of corneas operated on for refractive surgery [LASIK or photorefractive keratectomy (PRK)] will become a major concern for eye banks in the coming years... 相似文献
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