Viscoelastic spectrum analysis and the identification of a fung viscoelastic material

Despite its many limitations, the Fung “quasi-linear viscoelastic” constitutive model continues to serve as a workhorse of the biomechanics community. A central challenge in applying the model is that it requires a specific form for the relaxation spectrum that is difficult to relate to easily obtained experimental spectra such as a generalized Maxwell relaxation spectrum. Here, we present a simple and general technique for obtaining a from relaxation data a viscoelastic spectrum appropriate to the Fung model. We apply the model to identify several biomaterials that are modeled reasonably by a Fung model, and many more that are not

Hydro-alcoholic extract of Matricaria recutita exhibited dual anti-spasmodic effect via modulation of Ca2+ channels, NO and PKA2-kinase pathway in rabbit jejunum

Objective: Several studies have shown the antispasmodic activity of Matricariarecutita without detailing the underlying mechanism(s). The present study was designed to determine whether the antispasmodic mechanisms of M. recutita extract mediated via histaminergic/cholinergic receptors, Ca2+channels, activation of PKA2 and NO release in isolated rabbit jejunum. Methods and Materials: The concentration- dependent (3 × 10-3–1.3 × 10-2 mg/ml) antispasmodic effect of the hydro-alcoholic extract of M. recutita flowers was studied in isolated rabbit jejunum. The isolated jejunum preparations were divided into seven groups, including the pharmacological probes that modulate cholinergic, histaminergic, and nitrergic receptors, as well as PKA2. Results: M. recutita inhibited spontaneous smooth muscle contractility of the jejunum in a concentration-dependent manner (3 × 10-3–1.3 × 10-2 mg/ml) and reduced both K+- and Ca2+-induced contractions, which is similar to the effect of verapamil. The antispasmodic effect of M. recutita wasinhibited by H89 (a PKA2 inhibitor). The myorelaxant effect of M. recutita increased in the presence of ACh/His and H89. Conclusion: M. recutita evoked antispasmodic and spasmolytic effects mediated through different signaling pathways. Our results have shown this dual inhibitory effect is mediated by blocking Ca2+ channels, activating His and ACh receptors, releasing NO, and activating PKA2

Evaluation of the Effect of Pistacia atlantica Oleoresin on Blood Sugar, Pressure and Lipids in Patients With Type 2 Diabetes: A Single‐Blind, Placebo‐Controlled Trial

ABSTRACT Background Diabetes mellitus (DM) is a chronic metabolic disorder characterised by high blood sugar (BS) levels due to impaired insulin production or insulin resistance. It is a global health concern with significant implications for morbidity and mortality. Persian medicine has long utilised natural remedies, such as Pistacia atlantica Desf., for various diseases. In this randomised clinical trial, the effects of P. atlantica oleoresin in the improvement of lipid profiles, glucose indices and blood pressure (BP) were assessed in patients with Type 2 DM. Materials and Methods In this randomised, single‐blind, placebo‐controlled study, 42 patients with Type 2 DM were randomly allocated to receive either P. atlantica oleoresin or placebo capsule for 3 months. Patients were evaluated prior to and 12 weeks after the beginning of the intervention, in terms of changes in lipid profiles, glucose indices and BP. Results After 3 months, the mean BP in patients with DM receiving P. atlantica oleoresin was significantly reduced compared with the baseline (p = 0.001). Also, these changes were significantly higher than those of the control group. The mean of total cholesterol (p = 0.89), low‐density lipoprotein (LDL) (p = 0.43) and triglyceride (TG) (p = 0.98) in the intervention group after 3 months was lower than that in the control group, but this difference was not statistically significant. Conclusion After 3 months, there was no significant difference between the P. atlantica and control groups in terms of blood sugar and lipid profiles. The mean BP in patients with DM receiving P. atlantica oleoresin was significantly reduced compared with that in the beginning of the study. Also, these changes were significant compared with the control group

The effects of ATO on mitochondria apoptosis pathway genes expression in APL cell line

Abstract Purpose and Background: Acute promyelocystic leukemia is the most malignant acute leukemia that leads to death in few weeks. It constitutes 10-15% of acute myelocystic leukemia. Arsenic trioxide, as a single agent factor, is known as the best treatment for acute promyelocystic leukemia, which mainly functions by inducing apoptosis. However, there is no clear image of the mechanism through which apoptosis is induced and how the genes expression is deeply affected. Thus, the present study is an attempt to examine the effect of the agent on expression of the genes dealing with the cancer. Methodology: The study was carried out as an analytical work. To find out about the mechanisms effective on inducing apoptosis, cell line NB4 were cultured with 0.5µM, 1 µM, and 2 µM arsenic trioxide and their RNA was extracted after 12hrs, 24hrs, 28hrs, and 72hrs. Following cDNA synthesis, apoptosis genes expression at mitochondria pathway including caspase 3, Mcl-1, and Bcl-2 were examined using Real-Time PCR. The data was analyzed using t-test and variance analysis in Excel. Findings: It was found that arsenic caused apoptosis was featured with decrease of mRNA expression of Bcl-2 anti-apoptotic. However, expression of caspase 3 and Mcl-1 genes remained unchanged after culturing by arsenic. Conclusion: The results showed that changes in Bcl-2 gene expression can be considered as a mechanism of apoptosis caused by arsenic, while caspase 3 and Mcl-1 genes had no effect on the mechanism