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621.
N Azila F K Siao I Othman 《Comp. Biochem. Physiol. C, Comp. Pharmacol. Toxicol.》1991,99(1-2):153-156
1. An extract prepared from the tentacle of the jellyfish (CE), Catostylus mosaicus exhibited haemolytic, oedema and haemorrhage-inducing activities. 2. Acetone treatment of the tentacle extract produced an acetone soluble extract (AE) which showed an increase in specific haemolytic and haemorrhagic activities by 25- and 120-fold respectively; the minimum oedema dose was reduced by 30-fold. 3. The AE caused a rapid onset of oedema in the mouse foot pad. The effect was long-lasting, reaching a maximum in about 30 min after injection and sustained up to 4 hr. 4. Fractionation of the AE on Q-Sepharose gave 4 bound fractions which induced oedema and haemorrhage; however only 3 of the fractions exhibited haemolytic activity. 相似文献
622.
Hania Hamrouni Khadija Ben Othman Hasnia Benmoussa Sourour Idoudi Hanen Najjaa Mohamed Neffati Walid Elfalleh 《化学与生物多样性》2023,20(8):e202300265
Phytochemical screening of aqueous extract from six medicinal wild plants grown in South-eastern of Tunisia: Atriplex halimus, Teucrium polium, Moricandia arvensis, Deverra tortuoa, Haplophyllum tuberculatum and Polygonum equisetiforme were evaluated. Both decoction and ultrasound assisted extraction were used. Antioxidant, antibacterial proprieties, and phenolic profiling, using LC-ESI-MS method, were assessed. Total polyphenols, flavonoids, and condensed tannins contents ranged from 7.47±0.19 to 22.25±0.49 mg GAE/g Dw, 5.47±0.06 to 7.55±0.07 mg RE/g Dw, and 0.33±0.02 to 19.43±0.64 mg TAE/g Dw, respectively. Moreover, the reducing power and DPPH tests showed that P. equisetiforme (EC50: 12.50±0.50 μg/ml; DPPH⋅+: 213.49±4.24 mg TEAC/g DW), T. polium (EC50: 25.00±1.00 μg/ml; DPPH⋅+: 181.39±9.47 mg TEAC/g DW) as well as H. tuberculatum (EC50: 56.25±0.25 μg/ml; DPPH⋅+: 177.83±5.85 mg TEAC/g DW) extracts were the most effective natural antioxidants. For anti-bacterial activity, the ultrasonic extract of H. tuberculatum showed the highest activity against both P. aeruginosa (13.50±0.71 mm) and S. aureus (13.00±0.00 mm) at 10 mg/ml. Furthermore 24 phenolic compounds were identified, with predominance of quinic acid, gallic acid, protocatechuic acid, syringic acid, p-coumaric acid, trans-ferulic acid, catechin (+), trans-cinnamic and silymarin. These results were further consolidated by to heatmap clustering with P. equisetiforme, H. tuberculatum, T. polium as the main antioxidant and antibacterial sources which supports their domestication and industrial use. 相似文献
623.
Prof. Gokhan Zengin Ass. Prof. Nada M. Mostafa Dr. Yasmin M. Abdelkhalek Prof. Omayma A. Eldahshan 《化学与生物多样性》2023,20(9):e202300117
Rhoifolin (apigenin-7-O-β-neohesperidoside) belongs to the class of flavonoids and was reported to exhibit anti-inflammatory, cytotoxic, antidiabetic, hepatoprotective, and cardioprotective activities. The current study presents the in-vitro evaluation of the antioxidative effects of rhoifolin by many assays, namely DPPH, CUPRAC, ABTS, phosphomolybdenum, and FRAP. Enzyme inhibitory potential was also evaluated for acetylcholinesterase (AChE), butyrylcholinesterase (BChE), tyrosinase, amylase, and glucosidase enzymes. While results revealed weak antioxidant activities for rhoifolin, the compound demonstrated some promising enzyme inhibitory effects against BChE (4.03 mg GALAE/g) and tyrosinase (7.44 mg KAE/g) but was not active on AChE. Regarding anti-diabetic enzymes, the compound was active on amylase but did not show any inhibition effect on glucosidase. In-silico molecular docking study was performed for rhoifolin on the active site of NADPH oxidase, BChE, and amylase enzymes to verify the observed enzyme inhibitory effect. Good binding affinities were observed for rhoifolin on all the docked enzymes, revealing numerous hydrogen bonds, carbon-hydrogen, van der Waals interactions. This is the first study to evaluate the enzyme inhibition potential of rhoifolin. We concluded that the increase in the degree of glycosylation might decrease the antioxidant abilities of flavonoids and that rhoifolin had moderate enzyme inhibition abilities to be investigated in future studies. 相似文献
624.
Chouayekh Hichem Farhat-Khemakhem Ameny Karray Fatma Boubaker Insaf Mhiri Najla Abdallah Manel Ben Alghamdi Othman A. Guerbej Hamadi 《Probiotics and antimicrobial proteins》2023,15(1):30-43
Probiotics and Antimicrobial Proteins - Probiotics or direct-fed microbials (DFM) have proven strong potential for improving aquaculture sustainability. This study aims to evaluate the effects of... 相似文献
625.
Yasmin Ayob 《Biologicals》2010,38(1):91-96
Hemovigilance like quality systems and audits has become an integral part of the Blood Transfusion Service (BTS) in the developed world and has contributed greatly to the development of the blood service. However developing countries are still grappling with donor recruitment and efforts towards sufficiency and safety of the blood supply. In these countries the BTS is generally fragmented and a national hemovigilance program would be difficult to implement. However a few developing countries have an effective and sustainable blood program that can deliver equitable, safe and sufficient blood supply to the nation. Different models of hemovigilance program have been introduced with variable success. There are deficiencies but the data collected provided important information that can be presented to the health authorities for effective interventions.Hemovigilance program modeled from developed countries require expertise and resources that are not available in many developing countries. Whatever resources that are available should be utilized to correct deficiencies that are already apparent and obvious. Besides there are other tools that can be used to monitor the blood program in the developing countries depending on the need and the resources available. More importantly the data collected should be accurate and are used and taken into consideration in formulating guidelines, standards and policies and to affect appropriate interventions. Any surveillance program should be introduced in a stepwise manner as the blood transfusion service develops. 相似文献
626.
Olfactory neuroepithelium (ONe) is unique because it contains progenitor cells capable of mitotic division that replace damaged or lost neurons throughout life. We isolated populations of ONe progenitors from adult cadavers and patients undergoing nasal sinus surgery that were heterogeneous and consisted of neuronal and glial progenitors. Progenitor lines have been obtained from these cultures that continue to divide and form nestin positive neurospheres. In the present study, we used clonal and population analyses to probe the self-renewal and multipotency of the neurosphere forming cells (NSFCs). NSFCs plated at the single cell level produced additional neurospheres; dissociation of these spheres resulted in mitotically active cells that continued to divide and produce spheres as long as they were subcultured. The mitotic activity of clonal NSFCs was assessed using bromodeoxyuridine (BrdU) incorporation. Lineage restriction of the clonal cultures was determined using a variety of antibodies that were characteristic of different levels of neuronal commitment: β-tubulin isotype III, neural cell adhesion molecule (NCAM) and microtubule associated protein (MAP2), or glial restriction: astrocytes, glial fibrillary acidic protein (GFAP); and oligodendrocytes, galactocerebroside (GalC). Furthermore, nestin expression, a marker indicative of progenitor nature, decreased in defined medium compared to serum-containing medium. Therefore, adult human ONe-derived neural progenitors retain their capacity for self-renewal, can be clonally expanded, and offer multipotent lineage restriction. Therefore, they are a unique source of progenitors for future cell replacement strategies in the treatment of neurotrauma and neurodegenerative diseases. 相似文献
627.
628.
629.
Horan M Newsway V Yasmin Lewis MD Easter TE Rees DA Mahto A Millar DS Procter AM Scanlon MF Wilkinson IB Hall IP Wheatley A Blakey J Bath PM Cockcroft JR Krawczak M Cooper DN 《Human genetics》2006,119(5):527-540
An increased prevalence of both hypertension and cerebrovascular stroke is apparent in growth hormone (GH) deficiency whilst hypertension is a frequent complication in acromegaly. This has suggested a possible link between GH, stature and arterial function. Since the risk of both hypertension and stroke also appears to be inversely correlated with adult height, we have instigated an exploratory study to assess whether inter-individual variation in the genes encoding human growth hormone (GH1) and the GH receptor (GHR) might be associated with an increased risk of hypertension and stroke. GH1 promoter haplotypes were found to differ significantly not only between hypertensive patients (n=111) and controls (n=121) but also between stroke patients (n=155) and controls (n=158). Intriguingly, the association between GH1 promoter haplotype and risk of hypertension was much greater in females than in males. An inverse correlation between height and central systolic blood pressure was apparent in both hypertensive patients and normal controls but was much stronger in individuals carrying at least one GH1 promoter risk haplotype. The GH1 genotype therefore constitutes a risk factor for hypertension that interacts with stature. A strong association was found between the presence of at least one GH1 risk haplotype and a family history of stroke at an early age (odds ratio: 9.07, 95% confidence interval: 1.14–72.22). Three novel GH variants (Arg16His, Phe176Cys, Cys189Arg) were identified during the course of this study. Although two exhibited markedly reduced biological activity in vitro, their clinical significance remains unclear. No association was found between GHR genotype and either hypertension or stroke, nor was any interaction noted between GHR and GH1 genotypes in terms of a disease association. However, an association between GHRd3 genotype and hypertension was observed among stroke patients, particularly females. Elevated HDL was found to be a risk factor for hypertension in individuals lacking a copy of the GHRd3 allele. Weak associations with GHR genotype were also noted for peripheral systolic and diastolic blood pressure in hypertensive patients. Although the underlying mechanisms are still unclear, our findings are consistent with a complex relationship between height, hypertension, GH1 promoter haplotype, GHR polymorphism and the risk of stroke. 相似文献
630.
Sjöling A Qadri F Nicklasson M Begum YA Wiklund G Svennerholm AM 《Microbes and infection / Institut Pasteur》2006,8(12-13):2797-2802
Enterotoxigenic Escherichia coli (ETEC) colonize the intestine and adhere to the epithelium by means of different host specific colonization factors (CFs). Colonizing ETEC produce one or both of two enterotoxins; the heat stable (ST) and heat labile (LT) toxins which are both able to cause diarrhoea. The regulation of virulence genes in ETEC during infection of the human intestine is mainly unknown. In this study we analysed the level of mRNA expression of estA, coding for ST, and eltB, coding for the B subunit of LT, during human infection. The expressions of the toxins in ETEC strains expressing both ST and LT were investigated in bacteria isolated directly from patient stool without sub-culturing, (in vivo) and compared to the expression pattern of the corresponding ST/LT strains grown in liquid broth (in vitro) by quantitative competitive RT-PCR using fluorescent primers. We found that estA and eltB are expressed in the in vivo samples but no significant up-or down regulation of the expression levels of either estA or eltB could be determined in vivo as compared to in vitro. 相似文献