2,132 research outputs found
Generalized Coefficients for Hopf Cyclic Cohomology
A category of coefficients for Hopf cyclic cohomology is defined. It is shown
that this category has two proper subcategories of which the smallest one is
the known category of stable anti Yetter-Drinfeld modules. The middle
subcategory is comprised of those coefficients which satisfy a generalized SAYD
condition depending on both the Hopf algebra and the (co)algebra in question.
Some examples are introduced to show that these three categories are different.
It is shown that all components of Hopf cyclic cohomology work well with the
new coefficients we have defined
The anti-infarct, antistunning and antiarrhythmic effects of oleuropein in isolated rat heart
Previous studies have reported that oleuropein, the major constituent of olive leaves, has cardioprotective effects. There is no report related to oleuropein and ischemic-reperfusion injuries (cardiac dysfunction and myocardial infarction) as well as preconditioning in rat hearts.
56 male Wistar rats were divided into 7 groups (n=8). Group 1 as the control group and groups 2 to 7 as the treatment groups that received a single dose of oleuropein (100 mg/kg, i.p.) 1, 3, 6, 12, 24 and 48 hours before the excision of the heart, respectively. After these times, their hearts were excised and subjected to 30 min regional ischemia and 120 min reperfusion under Langendorff apparatus. Electrocardiogram and intraventricular pressures were monitored and recorded throughout the procedure. Finally, infarct size was measured by triphenyltetrazolium chloride staining.
Compared to the control group, oleuropein significantly reduced infarct size and reperfusion-induced cardiac dysfunction in groups 2 and 3. Oleuropein markedly attenuated both ischemic and reperfusion arrhythmias in groups 2 and 3. There was no significant difference between other groups (4 to 7) than the control group. Heart rate had no significant difference among all of the groups.
These results indicate that pretreatment of rats with a single dose of intraperitoneal oleuropein could protect their heart against ischemic-reperfusion injury for at least 3 hours. However, it has no preconditioning effect, since oleuropein had not cardioprotective effects 24 hour later
The effects of Ramadan fasting on the health and function of the eye
Background: Ramadan fasting may alter a variety of physiological parameters which by themselves influence ocular system. Here, we
review the effects of Ramadan fasting on the health and function of the eye. Materials and Methods: Literature records in PubMed/
MEDLINE, Web of Science, EMBASE, Google Scholar, and Iran Medex databases as well as proceedings of related meetings from January
1986 to March 2014 were systematically reviewed. The search key words was based on the terms “Ramadan Fasting,” “Ramadan,” “Islamic
Fasting,” “Fasting in Ramadan” accompanied with one of the eye, tear drop, myopia, intraocular pressure (IOP), tear break up time, basal
tear secretion, refractive error, and visual acuity. Results: Predawn water loading and dehydration in the evening are shown to increase and
decrease IOP and tear secretion, respectively. Ocular blood flow is changed in Ramadan fasting, and patients with ocular vein occlusion
may experience more frequent attacks. There are no or minimal fluctuations in visual acuity and refractive errors, but most of them are
decompensated after Ramadan. Conclusion: Although the influence of fasting in different eye parameters is evaluated in several studies,
there are no or only limited studies conducted on patients suffering from glaucoma, damage to ophthalmic vasculature, tear dysfunction,
and minimal visual acuity. Such studies are required to make a definite decision before fasting is declared harmless to these patients
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