658 research outputs found

    The effect of vitamin E on mast cells in small intestine of broilers under heat stress

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    ΔΕΝ ΥΠΑΡΧΕΙ ΕΛΛΗΝΙΚΗ ΠΕΡΙΛΗΨΗThe aim of this study is to identify the effect of vitamin E (DL-α-tocopherol acetate) (300 IU/kg) on mast cells in the small intestine (duodenum, jejunum and ileum) under heat stress. In the study, 42 one-day-old Ross 308 male broiler chicks were used. The chicks were randomly separated into 3 groups as follows; control (22±2°C), heat stress (35°C, 5 hours/per day) and vitamin E (300 IU/kg/per day) + heat stress (35°C, 5 hours/per day). The applications of heat stress and vitamin E began on the fifteenth day and ended on the thirty-fifth day. Tissue samples were taken from animals in each group of four and five-week-old chickens. Tissue samples were fixed in BLA (Basic Lead Acetate) solution. The sections were stained with toluidine blue (TB) (pH 0.5) and alcian blue-critical electrolyte concentration (AB-CEC) (pH 5.8, 0.3 M MgCl2) / Safranin O (SO) (pH 1.0) combined method. It was determined that increasing of the exposure duration to heat stress increased the number of mast cells in the small intestine of the boilers. Also, it was revealed that vitamin E reduced mast cell population under heat stress. Consequently, heat stress may play a role in the pathogenesis of small intestine-associated with disorders and the supplementation of vitamin E can contribute to regulate small intestine functions of broilers by decreasing mast cell proliferation and activation under heat stress

    Mercury in the human adrenal medulla could contribute to increased plasma noradrenaline in aging

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    Plasma noradrenaline levels increase with aging, and this could contribute to the sympathetic overactivity that is associated with essential hypertension and the metabolic syndrome. The underlying cause of this rise in noradrenaline is unknown, but a clue may be that mercury increases noradrenaline output from the adrenal medulla of experimental animals. We therefore determined the proportion of people from 2 to 104 years of age who had mercury in their adrenal medulla. Mercury was detected in paraffin sections of autopsied adrenal glands using two methods of elemental bioimaging, autometallography and laser ablation-inductively coupled plasma-mass spectrometry. Mercury first appeared in cells of the adrenal medulla in the 21–40 years group, where it was present in 52% of samples, and increased progressively in frequency in older age groups, until it was detected in 90% of samples from people aged over 80 years. In conclusion, the proportion of people having mercury in their adrenal medulla increases with aging. Mercury could alter the metabolism of catecholamines in the adrenal medulla that leads to the raised levels of plasma noradrenaline in aging. This retrospective autopsy study was not able to provide a definitive link between adrenal mercury, noradrenaline levels and hypertension, but future functional human and experimental studies could provide further evidence for these associations

    Elemental imaging shows mercury in cells of the human lateral and medial geniculate nuclei.

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    OBJECTIVE:Interference with the transmission of sensory signals along visual and auditory pathways has been implicated in the pathogenesis of hallucinations. The relay centres for vision (the lateral geniculate nucleus) and hearing (the medial geniculate nucleus) appear to be susceptible to the uptake of circulating mercury. We therefore investigated the distribution of mercury in cells of both these geniculate nuclei. MATERIALS AND METHODS:Paraffin-embedded tissue sections containing the lateral geniculate nucleus were obtained from 50 adults (age range 20-104 years) who at autopsy had a variety of clinicopathological conditions, including neurological and psychiatric disorders. The medial geniculate nucleus was present in seven sections. Sections were stained for mercury using autometallography. Laser ablation-inductively coupled plasma-mass spectrometry was used to confirm the presence of mercury. RESULTS:Ten people had mercury in cells of the lateral geniculate nucleus, and in the medial geniculate nucleus of three of these. Medical diagnoses in these individuals were: none (3), Parkinson disease (3), and one each of depression, bipolar disorder, multiple sclerosis, and mercury self-injection. Mercury was distributed in different groups of geniculate capillary endothelial cells, neurons, oligodendrocytes, and astrocytes. Mass spectrometry confirmed the presence of mercury. CONCLUSION:Mercury is present in different combinations of cell types in the lateral and medial geniculate nuclei in a proportion of people from varied backgrounds. This raises the possibility that mercury-induced impairment of the function of the geniculate nuclei could play a part in the genesis of visual and auditory hallucinations. Although these findings do not provide a direct link between mercury in geniculate cells and hallucinations, they suggest that further investigations into the possibility of toxicant-induced hallucinations are warranted

    The distribution of toxic metals in the human retina and optic nerve head: Implications for age-related macular degeneration.

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    OBJECTIVE:Toxic metals are suspected to play a role in the pathogenesis of age-related macular degeneration. However, difficulties in detecting the presence of multiple toxic metals within the intact human retina, and in separating primary metal toxicity from the secondary uptake of metals in damaged tissue, have hindered progress in this field. We therefore looked for the presence of several toxic metals in the posterior segment of normal adult eyes using elemental bioimaging. METHODS:Paraffin sections of the posterior segment of the eye from seven tissue donors (age range 54-74 years) to an eye bank were examined for toxic metals in situ using laser ablation-inductively coupled plasma-mass spectrometry, a technique that detects multiple elements in tissues, as well as the histochemical technique of autometallography that demonstrates inorganic mercury, silver, and bismuth. No donor had a visual impairment, and no significant retinal abnormalities were seen on post mortem fundoscopy and histology. RESULTS:Metals found by laser ablation-inductively coupled plasma-mass spectrometry in the retinal pigment epithelium and choriocapillaris were lead (n = 7), nickel (n = 7), iron (n = 7), cadmium (n = 6), mercury (n = 6), bismuth (n = 5), aluminium (n = 3), and silver (n = 1). In the neural retina, mercury was present in six samples, and iron in one. Metals detected in the optic nerve head were iron (N = 7), mercury (N = 7), nickel (N = 4), and aluminium (N = 1). No gold or chromium was seen. Autometallography demonstrated probable inorganic mercury in the retinal pigment epithelium of one donor. CONCLUSION:Several toxic metals are taken up by the human retina and optic nerve head. Injury to the retinal pigment epithelium from toxic metals could damage the neuroprotective functions of the retinal pigment epithelium and allow toxic metals to enter the outer neural retina. These findings support the hypothesis that accumulations of toxic metals in the retina could contribute to the pathogenesis of age-related macular degeneration

    Descent methods for mixed variational inequalities in a Hilbert space

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    In this paper, properties of merit functions for mixed variational inequalities involving a differentiable cost mapping and a convex nondifferentiable function are considered under a Hilbert space setting, thus extending the previous results in a finite-dimensional space. Moreover, we consider several descent methods for the above problem under various monotonicity assumptions on the cost mapping

    On convergence of descent methods for variational inequalities in a Hilbert space

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    In this paper, properties of differentiable gap functions for variational inequalities and convergence of the corresponding descent methods under a Hilbert space setting are considered. We give various convergence results under different assumptions on the cost mapping, including the monotone case

    Relationship between platelet parameters and sudden sensorineural hearing loss: a systematic review and meta-analysis

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    Background: Sudden deafness or sudden sensorineural hearing loss (SSNHO is defined as sensorineural hearing loss of greater than 30 dB over 3 contiguous puretone frequencies occurring within 3 days' periodObjective: To investigate the relationship of some platelet parameters including platelet count (PC), mean platelet volume (MPV) and platelet distribution width (PDW) with the occurrence of SSNHL.Data source: A PubMed, Science Direct, Scopus, OVID, EMBASE and Google Scholar search (date last searchedApril2016) search was done. No restrictions of time, language and location were placed.Study selection: All case-control studies which have been studied the relationship of PC, MPV and PDW with the occurrence of SSNHL were included in the meta-analysis.Data extraction: The required data from selected studies including the title, authors, publication date, location of study, sample size of patients and control groups, number of withdrawals, the mean and standard deviation of PC, MPV and PDW for patients and control groups and the result of different tests were extracted and entered to EX CELL.Data synthesis: A total of 9 case-control studies were r found in our search from them 8 studies have reported mean PC, 7 studies have reported mean MPV and 4 studies have reported mean PDW. Our analysis showed that mean PC of patients is 0.03 (-0.14-0.20) unit higher than that of controls with 95% CI which is not statistically significant. Also, mean MPV of patients is 0.31 (-0.03-0.65) unit higher than that of controls with 95% CI which is statistically not significant too. Finally, mean PDW of patients is 0.70 (0.03- 1.37) unit higher than that of controls with 95% CI which is statistically significant.Conclusions: Our study confirmed only the probable relationship of PDW and SSNHL but due to the limited studies on this subject more studies is needed

    The future of enterprise groupware applications

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    This paper provides a review of groupware technology and products. The purpose of this review is to investigate the appropriateness of current groupware technology as the basis for future enterprise systems and evaluate its role in realising, the currently emerging, Virtual Enterprise model for business organisation. It also identifies in which way current technological phenomena will transform groupware technology and will drive the development of the enterprise systems of the future
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