Effect of receiver shape and volume on the Alzheimer disease for molecular communication via diffusion.

Nano-devices are featured to communicate via molecular interaction, the so-called molecular communication (MC). In MC systems, the information is carried by molecules where the amount of molecules constitutes the level of the signal. In this study, an MC-based system was analysed with different receiver topology and related parameters, such as size, shape, and orientation of receptors on the receiver. Also in the concept of nano-medicine, the effect of amyloid-beta ([inline-formula removed]), which is believed as the main cause of Alzheimer disease, on the successful reception ratio of molecules with the proposed receiver models was investigated. It was demonstrated that the cubic receiver model is superior to sphere one in terms of the correct reception ratio of the molecular signal. A cubic model where its edge (not rotated around the centre) is placed across the transmitter demonstrated a better performance in reducing the effect of [inline-formula removed] as compared to the sphere model while a cubic model where its corner (rotated around the centre) is placed across the transmitter demonstrated a worse performance than the spherical model. From this expression, it may be concluded that with the adjustment of topological system parameters the probability of successful reception ratio in MC may be possible.

Effects of Small-World Rewiring Probability and Noisy Synaptic Conductivity on Slow Waves: Cortical Network.

Physiological rhythms play a critical role in the functional development of living beings. Many biological functions are executed with an interaction of rhythms produced by internal characteristics of scores of cells. While synchronized oscillations may be associated with normal brain functions, anomalies in these oscillations may cause or relate the emergence of some neurological or neuropsychological pathologies. This study was designed to investigate the effects of topological structure and synaptic conductivity noise on the spatial synchronization and temporal rhythmicity of the waves generated by cells in the network. Because of holding the ability of clustering and randomizing with change of parameters, small-world (SW) network topology was chosen. The oscillatory activity of network was tried out by manipulating an insulated SW, cortical network model whose morphology is very close to real world. According to the obtained results, it was observed that at the optimal probabilistic rates of conductivity noise and rewiring of SW, powerful synchronized oscillatory small waves are generated in relation to the internal dynamics of cells, which are in line with the network's input. These two parameters were observed to be quite effective on the excitation-inhibition balance of the network. Accordingly, it may be suggested that the topological dynamics of SW and noisy synaptic conductivity may be associated with the normal and abnormal development of neurobiological structure.

Beneficial effects of dexpanthenol on mesenteric ischemia and reperfusion injury in experimental rat model.

BACKGROUND AND AIM: It has been reported that intestinal ischemia-reperfusion (I/R) injury results from oxidative stress caused by increased reactive oxygen species. Dexpanthenol (Dxp) is an alcohol analogue with epitelization, anti-inflammatory, antioxidant, and increasing peristalsis activities. In the present study, the aim was to investigate protective and therapeutic effects of Dxp against intestinal I/R injury. MATERIALS AND METHODS: Overall, 40 rats were assigned into five groups including one control, one alone Dxp, and three I/R groups (40-min ischemia; followed by 2-h reperfusion). In two I/R groups, Dxp (500 mg/kg, i.m.) was given before or during ischemia. The histopathological findings including apoptotic changes, and also tissue and serum biochemical parameters levels, were determined. Oxidative stress and ileum damage were assessed by biochemical and histological examination. In the control (n = 8) and alone Dxp (n = 8; 500 mg/kg, i.m. of Dxp was given at least 30 min before recording), groups were incised via laparotomy, and electrical activity was recorded from their intestines. In this experiment, the effect of Dxp on the motility of the intestine was examined by analyzing electrical activity. RESULTS: In ileum, oxidant levels were found to be higher, while antioxidant levels were found to be lower in I/R groups when compared with controls. Dxp approximated high levels of oxidants than those in the control group, while it increased antioxidant values compared with I/R groups. Histopathological changes caused by intestinal I/R injury and histological improvements were observed in both groups given Dxp. In the Dxp group, electrical signal activity markedly increased compared with the control group. CONCLUSIONS: Here, it was seen that Dxp had protective and therapeutic effects on intestinal I/R injury and gastrointestinal system peristaltism.

Dual effects of melatonin on uterine myoelectrical activity of non-pregnant rats.

OBJECTIVE: In this experimental study, we aimed to investigate the role of melatonin on uterine myoelectrical activity of non-pregnant rats. MATERIAL AND METHODS: Forty-six female rats were assigned to six groups: (1) control; (0.2 mL 0.9% NaCl was injected intravenously (IV), n=6); (2) melatonin applied as 0.4 mg/kg/IV (n=8); (3) melatonin applied as 4 mg/kg/IV (n=8); (4) single dose of oxytocin (100 mU/kg) injected IV (n=8); (5) melatonin (0.4 mg/kg) plus oxytocin (100 mU/kg) (n=8); and (6) melatonin (4 mg/kg) plus oxytocin (100 mU/kg) injected IV (n=8). Each rat underwent a laparotomy, and uterine myoelectrical signals were recorded. The mean spectrum, averaged over the spectral content of signals in each group, was compared. RESULTS: Melatonin induced uterine myoelectrical activity in a dose-dependent manner. Treatment of melatonin after oxytocin suppressed the mean power of the signals. Serum melatonin concentrations were significantly higher in melatonin-treated rats. CONCLUSION: Melatonin itself at two different dose levels was found to be equally effective in stimulating the uterine electrical signals, although oxytocin-induced uterine electrical activity was suppressed by melatonin. These findings merit further investigations on the possible beneficial role of melatonin in the treatment of conditions associated with abnormal uterine activity.

Effects of electromagnetic radiation from 3G mobile phone on heart rate, blood pressure and ECG parameters in rats.

Effects of electromagnetic energy radiated from mobile phones (MPs) on heart is one of the research interests. The current study was designed to investigate the effects of electromagnetic radiation (EMR) from third-generation (3G) MP on the heart rate (HR), blood pressure (BP) and ECG parameters and also to investigate whether exogenous melatonin can exert any protective effect on these parameters. In this study 36 rats were randomized and evenly categorized into 4 groups: group 1 (3G-EMR exposed); group 2 (3G-EMR exposed + melatonin); group 3 (control) and group 4 (control + melatonin). The rats in groups 1 and 2 were exposed to 3G-specific MP's EMR for 20 days (40 min/day; 20 min active (speech position) and 20 min passive (listening position)). Group 2 was also administered with melatonin for 20 days (5 mg/kg daily during the experimental period). ECG signals were recorded from cannulated carotid artery both before and after the experiment, and BP and HR were calculated on 1st, 3rd and 5th min of recordings. ECG signals were processed and statistically evaluated. In our experience, the obtained results did not show significant differences in the BP, HR and ECG parameters among the groups both before and after the experiment. Melatonin, also, did not exhibit any additional effects, neither beneficial nor hazardous, on the heart hemodynamics of rats. Therefore, the strategy (noncontact) of using a 3G MP could be the reason for ineffectiveness; and use of 3G MP, in this perspective, seems to be safer compared to the ones used in close contact with the head. However, further study is needed for standardization of such an assumption.