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A Husband

Publications and source records attributed to A Husband.

15 recordsLinked to original sources

Comparison between phytoestrogens and estradiol in the prevention of atheroma in ovariectomized cholesterol-fed rabbits.

OBJECTIVES: There is increasing interest in the role of complementary and alternative medicines for the treatment of menopause-related problems. This study compared the preventive effect on atheroma formation of a commercially available mixed phytoestrogen concentrate with that of estradiol. METHODS: An ovariectomized cholesterol-fed rabbit model of atheroma formation was used. Rabbits were ovariectomized before the commencement of the 12-week treatment period. There were two control groups. Control Group 1 received isoflavone-free rabbit chow whilst Control Group 2 received 1% cholesterol-enriched isoflavone-free rabbit chow. Rabbits in Group 3 received 1% cholesterol-enriched isoflavone-free rabbit chow plus a 500 mg tablet containing a concentrated extract of Trifolium pretense (red clover). Rabbits in Group 4 received 1% cholesterol-enriched isoflavone-free rabbit chow plus a 0.5 mg tablet of oral estradiol. Atheroma formation was measured by, first, calculation of the area of atheroma on the intimal surface, and, second, measuring the cholesterol content in the aorta. RESULTS: There were no significant differences in serum cholesterol between the cholesterol-fed control Group 2 and the treatment Groups 3 and 4. However, there was significantly less staining for atheroma and significantly less cholesterol accumulation in the aorta in Group 4 (estradiol-treated) rabbits compared with either control Group 2 or Group 3 (phytoestrogen-treated) rabbits. CONCLUSION: In this study, only estradiol was shown to have a significant protective effect against atheroma formation.

Administration, Oral↗

The isoflavone metabolite dehydroequol produces vasodilatation in human resistance arteries via a nitric oxide-dependent mechanism.

BACKGROUND: Isoflavones (phytoestrogens) offer potential cardioprotective benefits. We recently reported on the vasodilatory activity of the isoflavone metabolite, dehydroequol, in rat isolated aortic ring preparations. In the current study, we examine the effect of this metabolite on the vascular haemodynamic profile in human forearm resistance arteries. METHODS AND RESULTS: Responses to brachial artery infusion of dehydroequol (0.1, 0.3, 1 and 3 micromol/min) in forearm resistance arteries were obtained in six healthy males. These were done, on two separate occasions, in the absence and presence of endogenous nitric oxide synthase inhibition using NG-monomethyl-L-arginine, with sufficient sodium nitroprusside to maintain vascular tone. Dehydroequol produced a dose-dependent increase in forearm blood flow from 2.44 +/- 0.37 (basal) to 5.25 +/- 1.07 mL/100 mL/min (P < 0.05) at dehydroequol 3 micromol/min. Responses to dehydroequol were significantly dampened with inhibition of endogenous nitric oxide synthase (at 3 micromol/min: % increase in forearm blood flow fell from 114.3 +/- 22.81 to 19.45 +/- 9.19; P < 0.01). CONCLUSION: This is the first report of dehydroequol, a metabolite derived from the isoflavone diadzein, demonstrating potent vasodilatory properties in human resistance arteries via a nitric oxide-dependent mechanism.

Adult↗

Phenoxodiol, a novel isoflavone derivative, inhibits dimethylbenz[a]anthracene (DMBA)-induced mammary carcinogenesis in female Sprague-Dawley rats.

The present study was undertaken to evaluate the potential cancer chemopreventive effects of novel synthetic derivatives of isoflavones. Initially these agents were tested in a mouse mammary organ culture (MMOC) model. Phenoxodiol (2H-1-benzopyran-7-O1,3-(4-hydroxyphenyl)), the most effective in this assay, was selected for further testing in female Sprague-Dawley rats. The agent was tested at 0 (basal diet), 50 and 75 mg/kg diet. Mammary carcinomas in these three groups were induced by dimethylbenz[a]anthracene (DMBA) injected 1 week after the animals started eating the experimental diets. Phenoxodiol significantly reduced tumour incidence rate at both doses (P<or=0.05). Tumour latency was increased from 70.4 days in the control group to 92.9 (P=0.04) days and 97.8 (P=0.03) days in the groups that were fed 50 and 75 mg/kg phenoxodiol, respectively. Compared with the control that was fed basal diet, tumour multiplicity was reduced by 42% (P=0.04) in the group that was fed 50 mg/kg phenoxodiol and by 49% (P=0.01) in the group that was fed 75 mg/kg phenoxodiol. Two additional groups that were not exposed to DMBA, one fed the basal diet and the other a diet containing 75 mg/kg phenoxodiol, were free of tumours. These data suggest that phenoxodiol is an effective chemopreventive agent against DMBA-induced mammary carcinogenesis.

9,10-Dimethyl-1,2-benzanthracene↗

In the prostatic epithelium, dietary isoflavones from red clover significantly increase estrogen receptor beta and E-cadherin expression but decrease transforming growth factor beta1.

In mice fed a diet supplemented with red clover isoflavones the prostatic epithelium displays a significant increase in the production of estrogen receptor beta and the adhesion protein E-cadherin but a decrease in transforming growth factor beta1. These proteins are estrogenically-induced markers of proliferation, maintenance of histological architecture, preservation of cell phenotype and reduction of the potential for neoplastic and metastatic transformation. This study suggests that red clover isoflavones represent a non-toxic dietary treatment for prostatic hyperplasia and a reduction in the potential for neoplastic transformation.

Animal Feed↗

The vascular activity of some isoflavone metabolites: implications for a cardioprotective role.

Legume-derived isoflavones such as genistein, diadzein and equol have been associated with a reduction in risk of cardiovascular disease. In the current study, we explore the vascular activity of several isoflavone metabolites namely dihydrodaidzein, cis and trans-tetrahydrodaidzein and dehydroequol for potential cardioprotective properties. Rat isolated aortic rings were used. 17beta-oestradiol, equol, and all four of the metabolites studied significantly antagonized contractile responses to noradrenaline. The direct vasodilatory action of these compounds were examined and in contrast to 17beta-oestradiol, the vasodilatory effect of which was demonstrated to be endothelium independent, the dilatory action of all four compounds could be inhibited by endothelium denudation. Further, the dilatory action of both dihydrodaidzein and cis-tetrahydrodaidzein were inhibited by the nitric oxide synthase inhibitor, N(omega)-nitro-L-arginine (NOLA), by the soluble guanylate cyclase inhibitor, 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ) and by 40 mM KCl. Dilatory responses to dehydroequol and trans-tetrahydrodaidzein, on the other hand, were inhibited by 40 mM KCL but not by NOLA nor ODQ. Finally, we examined the protective potential of these compounds in inhibiting endothelium damage by oxidized low density lipoprotein (ox-LDL). Trans-tetrahydrodaidzein was at least 10 fold more potent than 17beta-oestradiol in protecting against ox-LDL induced damage. We conclude that the isoflavone metabolites, dihydrodaidzein, cis- and trans-tetrahydrodaidzein and dehydroequol, may potentially represent a novel series of cardioprotective therapeutics.

Animals↗

Dextran sulphate sodium-induced colitis is ameliorated in interleukin 4 deficient mice.

The importance of IL-4 and its effects in inflammatory bowel disease (IBD) was studied using the dextran sulphate sodium-induced model of experimental colitis. The model resembles ulcerative colitis in humans. IL-4 deficient mice and IL-4+/+ littermates were used to induce colitis. Activity of disease, extent of tissue damage, immunoglobulin isotypes, IFNgamma and IL-10 production was assessed. Both disease activity index (DAI) and histological scores were consistently lower in the IL-4 deficient mice than in the IL-4+/+ littermates. Furthermore, the lower histological scores reflected the milder inflammatory lesions and decreased ulceration found in the IL-4 deficient mice. Analysis of immunoglobulin subtypes showed that IgG1 was almost absent in the sera of IL-4 deficient mice. IFNgamma contents was much higher in colonic tissues from IL-4 deficient mice. Dextran sulphate sodium-induced colitis is ameliorated in IL-4 deficient mice. IL-4 either directly or through its effects on T and B cells influences its severity. It is unclear if the higher immunoglobulin-producing cells in the colonic tissues of IL-4 deficient mice before colitis was induced could have influenced the outcome of the disease. The high IFNgamma contents in colonic tissues of IL-4 deficient mice argue against the role of this cytokine as a crucial mediator of tissue damage during the acute phase of colitis.

Animals↗

The in vivo effect of red clover diet on ventral prostate growth in adult male mice.

The incidence of clinically significant prostate disease in Asian men is lower than in Western men and appears to be influenced by dietary and environmental factors. The aim of this study was to examine the effect of dietary isoflavones on prostate growth in intact male mice using an extract of red clover. The results demonstrated that prostate, but not testis, size was significantly reduced over 28 days of a red clover isoflavone supplemented diet. Histological examination revealed an increase in apoptotic cells, rather than a reduction in proliferative activity in the epithelium. These findings support the hypothesis that dietary red clover isoflavones can induce apoptosis and lead to a reduction in prostate size.

Animal Feed↗

Safe and easy method for secondary tracheo-oesophageal puncture.

We describe a method for performing secondary tracheo-oesophageal puncture in patients who have undergone total laryngectomy. The technique is straightforward and easy. It uses a minimum of readily available equipment with a simple modification to a standard pharyngoscope.

Humans↗

Eosinophilia is attenuated in experimental colitis induced in IL-5 deficient mice.

Tissue eosinophilia is a feature of idiopathic inflammatory bowel disease and other forms of colonic inflammation but it is not clear whether the role of eosinophils in the disease process is to contribute to tissue damage. Interleukin 5 (IL-5) stimulates production and activation of eosinophils in vitro and enhances immunoglobulin A (IgA) production. As very little is known about the function of IL-5 in the colon, the aim of this study was to assess its role in colonic inflammation. IL-5 deficient mice were studied using the dextran sulphate sodium (DSS)-induced colitis model and the results compared to a congenic IL-5+/+ strain. The absence of IL-5 resulted in reduction of tissue eosinophilia (P < 0.0001) but was not reflected in differences in the severity of the disease (P > 0.5) or in the extent of tissue damage in this model of colitis. Numbers of immunoglobulin-containing cells in IL-5 deficient mice were similar to those in the IL-5+ mice. We conclude that the main role of IL-5 in DSS-induced colonic inflammation is to attract a population of eosinophils which do not appear to contribute significantly to the initiation or development of tissue damage in this model of colitis.

Animals↗

Different strains of Pseudomonas aeruginosa isolated from ocular infections or inflammation display distinct corneal pathologies in an animal model.

PURPOSE: The present investigation sought to define the responses of mouse eyes to challenge with three different strains of P. aeruginosa isolated from human corneas or contact lenses: two different strains produced an ulcerative keratitis, and one strain produced contact lens-induced acute red eye (CLARE). METHODS: The corneas of BALB/c mice were inoculated with three different strains of P aeruginosa. The strains were allowed to interact with the corneas for up to 24 h. In addition, strain Paerl, isolated from CLARE, was subjected to in vitro assays to measure its ability to invade corneal epithelial cells, or to produce cytotoxicity in these cells. Both these assays used cultured rabbit corneal epithelial cells. RESULTS: Both MK isolates were able to infect the corneas of mice, but the CLARE isolate was non-infective. The predominant response to infection with the cytotoxic strain was severe corneal edema and infiltration of the corneal stroma with polymorphonuclear leukocytes (PMNs). The predominant response with the invasive MK isolate was corneal ulceration and infiltration with PMNs. The CLARE strain produced only low levels of PMN infiltration. In in vitro assays the CLARE strain was non-invasive and non-cytotoxic. CONCLUSIONS: This study has identified that P. aeruginosa produces at least three different types of corneal pathology and that not all strains are able to infect mouse corneas.

Animals↗

Superficial siderosis of the central nervous system: an underestimated cause of hearing loss.

Superficial siderosis of the central nervous system (CNS) is a rare disease resulting in the accumulation of haemosiderin in the meninges, the brain surface, the spinal cord and the cranial nerves. The pigment is deposited as a result of chronic bleeding in the subarachnoid space. This produces a clinical picture of deafness, ataxia, cranial nerve deficits and in the latest stages dementia. In some cases the source of bleeding can be identified, whilst in others it can not. Despite its rarity the disease should be considered in the differential diagnosis of sensorineural deafness, particularly as it is a progressive and in some cases curable disease which is easily diagnosed by magnetic resonance imaging (MRI). In this case report the haemosiderin was derived from an ependymoma of the fourth ventricle with extension into the cerebello-pontine angle. The first symptom was a worsening sensorineural hearing loss.

Brain Neoplasms↗

Application of King's Theory of Nursing to the care of the adult with diabetes.

This paper demonstrates how King's theory of goal attainment can be applied to the care of the adult with diabetes mellitus. Salient components of King's theory are presented followed by application of the theory using the nursing process as a framework. An example of a nurse-patient interaction is used to more clearly present the application. The advantages of King's theory in relation to the care of the diabetic adult are also discussed.

Adult↗