Environmental factors are well‐accepted to play a complex and interdependent role with genetic factors in learning and memory. The goal of this study was to examine how environmental conditions ...altered synaptic plasticity in hippocampal area CA2. To do this, we housed adult mice for 3 weeks in an enriched environment (EE) consisting of a larger cage with running wheel, and regularly changed toys, tunnels and treats. We then performed whole‐cell or extracellular field recordings in hippocampal area CA2 and compared the synaptic plasticity from EE‐housed mice with slices from littermate controls housed in standard environment (SE). We found that the inhibitory transmission recruited by CA3 input stimulation in CA2 was significantly less plastic in EE conditions as compared to SE following an electrical tetanus. We demonstrate that delta‐opioid receptor (DOR) mediated plasticity is reduced in EE conditions by direct application of DOR agonist. We show that in EE conditions the overall levels of GABA transmission is reduced in CA2 cells by analyzing inhibition of ErbB4 receptor, spontaneous inhibitory currents and paired‐pulse ratio. Furthermore, we report that the effect of EE of synaptic plasticity can be rapidly reversed by social isolation. These results demonstrate how the neurons in hippocampal area CA2 are sensitive to environment and may lead to promising therapeutic targets.
•PTZ kindling impairs novelty-driven more than fear-driven exploration.•Reduced exploratory drive after kindling co-varies with poorer spatial memory.•Kindling induces hyperactivity within midbrain ...dopamine neurons.•Kindling blunts spatial novelty-induced activation of midbrain dopamine neurons.•Spatial detection and spatial motivation impairments may feed into each other.
Recurrent seizures that define epilepsy are often accompanied by psychosocial problems and cognitive deficits with incompletely understood aetiology. We therefore used the pentylenetetrazol (PTZ) kindling model of epilepsy in mice to examine potential seizure-associated neuropathologies, focusing on motivation, memory and novel-environment-induced activation of midbrain dopaminergic neurons. In addition to recurrent seizures, we found that PTZ kindling led to a strong suppression of novelty-driven exploration while largely sparing fear-driven exploration. The deficits in exploratory drive may be relevant for other cognitive impairments since reduced unassisted rearing in a learning arena correlated with poorer spatial memory of object location. Using c-Fos immunofluorescence as a marker of neuronal activity, we observed that dopamine neurons within the ventral tegmental area (VTA) of PTZ kindled mice demonstrate hyperactivity at baseline and hypoactivity in response to a novel environment compared to saline-injected cagemate controls. These data extend previous findings of PTZ kindling-mediated disruptions of hippocampal processes important for novel environment recognition and learning by demonstrating PTZ kindling also induces motivational deficits that are associated with reduced stimulus-evoked activation of VTA dopamine neurons. More broadly, these data help understand the aetiology of complex behavioural changes in the PTZ kindling model, and may assist in the development of superior diagnoses and treatments for epilepsy.
There are many differences among dorsal and ventral hippocampal neural circuits that affect the synaptic plasticity. In this study we compared the occurrence of short-term plasticity in the field ...excitatory post synaptic potentials (fEPSP) in dorsal and ventral hippocampal CA1 area following kindled seizures. Animals (male C57 B6/J mice, 12 weeks of age) were kindled by intraperitoneal injections of pentylenetetrazole (PTZ) and fEPSPs were recorded from dorsal and ventral hippocampal slices. Short-term plasticity was evaluated by measuring fEPSP-slope and fEPSP-area following paired-pulse stimulation delivered at three inter-pulse intervals (20, 80 and 160 ms). Obtained results showed that in control slices fEPSP-slope was greater in ventral- compared to dorsal hippocampus, but there was no difference in fEPSP-area among two regions. In hippocampal slices of kindled animals, fEPSP-slope was similar in dorsal and ventral regions, but fEPSP-area was greater in ventral- compared to dorsal hippocampus. In addition, fEPSP-area was greater in kindled compared to control group only in ventral hippocampus. PTZ kindled slices showed impaired short-term facilitation and the paired-pulse index was reduced only at dorsal hippocampal slices. Kindling had no significant effect on paired-pulse ratio in ventral hippocampal slices. Our findings indicated that the seizure occurrence affected the neural activity of hippocampus in a regional dependent manner. Although kindling increased fEPSP-area in ventral hippocampus, kindling-induced changes in short-term synaptic plasticity was significant only in dorsal hippocampal slices compared to control group. The difference in the responses of hippocampal dorsal and ventral poles has to be considered in the future researches.
Herein, a simple and cost‐effective method (solution electrospinning) is used to produce auxetic biobased polybutylene succinate membranes. The effect of fiber morphology, orientation, and alignment ...is investigated on the mechanical properties of the resulting membranes with a focus on Poisson's ratio. The degree of orientation is controlled by increasing the speed of the collector (from 4.03 to 11.01 m s
−1
) during membrane fabrication. The results indicate that membranes with oriented fibers show a more auxetic behavior than those with randomly orientated fibers. In particular, samples with a high level of alignment and tested in the transverse direction present higher negative Poisson's ratios (down to −5.73) compared to samples tested in the parallel direction (Poisson's ratios down to −2.90). However, samples tested in the transverse direction show lower tensile properties with higher dissipated energy and damping factor. Therefore, the level of fiber orientation and the number of fibers in the transverse and parallel directions are the most important parameters controlling the mechanical properties of electrospun membranes.
Administration of semelil (ANGIPARS™) has been successful in the treatment of diabetic foot ulcer. Considering the improvement of blood flow and anti-inflammatory effect that are attributed to this ...drug, we investigated its effect on cardiovascular performance in rabbits with isoproterenol (ISO) induced myocardial injury. Animal groups included: control group; ISO group, received ISO 50 mg/kg s.c. for two consecutive days; S1+ISO, S5+ISO and S10+ISO groups, received semelil 1, 5, and 10 mg/kg/day i.p. respectively, 30 min before ISO. On the 3(rd) day, electrocardiogram (ECG) and hemodynamic parameters were recorded; blood samples were taken and hearts were removed for lab investigations. ISO induced heart injury, ECG disturbance, raise of cardiac troponin I and significant decrease in LVSP (p<0.05), +dp/dt max (p<0.01), -dp/dt max (p<0.05) along with increase of LVEDP (p<0.01). Semelil had no significant effects on ECG and plasma cardiac troponin I. Impairment of +dp/dt max and -dp/dt max was significantly improved in S5+ISO and S10+ISO groups (P<0.05 versus ISO). In addition, LVSP and LVEDP was somewhat recovered in these groups, although semelil (1 mg/kg/day) to some extent exacerbated the myocardial lesions induced by ISO (P<0.05). Therefore, in stressful conditions, semelil may improve myocardial contractility; however, it may aggravate the severity of injury.
Around 5% of the world populations are the carriers of the hepatitis B virus. Prevalence of carriers in many different areas of the world is various. Iran, including the rate of 2 to 3%, is among ...countries, which has the average prevalence. The aim of this study was to determine the prevalence of antigen HBs positive and associated factors in pregnant women who had referred to urban health centers of Isfahan Province in 2009.
A descriptive study conducted on 1078 pregnant women who had referred to the urban health centers of Isfahan, Barkhovar, Meymeh, Khomeini Shahr, Lenjan and Najaf Abad in 2009 in order to register their physical condition and conducting pregnancy care. Random sampling method by quota was systematic. First, a questionnaire completed including demographic characteristics and records of high-risk behaviors in mothers and wives. Then, 4 cc of their blood drawn and evaluated the antigen surface in serum. Finally, the data were analyzed using SPSS15 software, Chi-square, Fisher and Logistic Regression tests.
According to the findings, serum of 0.5% of pregnant women under the study was HBsAg-positive. The average age of subjects was 26.1 (4.9) years old and the average pregnancy number was 1.79 (1.0). Using Fisher's test as well as logistic regression test and based on the previous records of high-risk sexual behaviors and tattooing, a significant difference was observed in positive-HBsAg group in comparison with negative-HBsAg group (p ≤ 0.05).
Instructing target groups and giving awareness in large-scale, close monitoring in high-risk centers such as beauty shops, tattooing centers and etc, and also staff training in how to use disposable and sterilized equipments have to be accomplished at the right time.
About 5% of the world population are carriers of the hepatitis B virus which is not the same in different areas of the world. Iran, with a rate of 2-3%, is among the countries with average ...prevalence. The aim of this study was to determine the prevalence of HBsAg and its associated factors in pregnant women who referred to urban health centers in Isfahan Province.
This was a descriptive study conducted on 1078 pregnant women who had referred to the urban health centers of Isfahan, Borkhar, Meymeh, Khomeini Shahr, Lenjan and Najaf Abad in 2009 in order to register their physical condition and receive pregnancy care. Random sampling method by quota was done. First, a questionnaire including demographic characteristics and history of high-risk behaviors in mothers and their husbands was completed. Then, a blood sample was taken and evaluated for the HB virus surface antigen. Finally, the data was analyzed using SPSS software, Chi-square, Fisher and Logistic Regression tests.
HB virus surface antigen was traced in the serum of 0.5% of the participants. The average age of subjects was 26.1± 4.9 (mean±sd) years old and the average pregnancy number was 1.79 + 1.0 (mean±sd). Using Fisher's test as well as logistic regression test and based on the previous history of high-risk sexual behaviors and tattooing, a significant difference was observed between the two groups with positive and negative HBsAg (p ≤ 0.05).
Instructing the target groups and close monitoring of the high-risk centers such as beauty shops, tattooing centers and etc, and also staff training on how to use disposable and sterilized equipments have to be accomplished at the right time.
•The potential of ultrasonic waves in the Zn/Cd solvent extraction was evaluated.•Solvent extraction of Zn/Cd was compared by ultrasonical and mechanical stirring.•D2EHPA selectively extract Zn ...rather than Cd in both UASX and MSSX systems.•Maximum extraction of Zn and Cd occurs at a narrow range of ultrasonic power.
This research was conducted to evaluate the potential of ultrasonic irradiation during the solvent extraction of metals, and comparing its efficiency with a mechanically stirred system (MSSX). The simultaneous extraction of zinc and cadmium from sulphate solutions was investigated by di-(2-ethylhexyl) phosphoric acid (D2EHPA) as an organic extractant which was diluted (20%) in kerosene at the organic: aqueous phase ratio of 1:1 and the temperature of 25°C. The influence of some critical parameters, including contact time, solution pH, ultrasonic power, and zinc/cadmium ratio were investigated on the extraction of the metals. Results show that D2EHPA selectively extract zinc rather than cadmium in both mechanically and ultrasonically mixed systems. It was also found that increase of ultrasonic power from 10 to 120W cause a small decrease in zinc extraction; while, at low and high levels of the induced power, cadmium extraction was significantly decreased. Results also show that maximum extraction amounts of zinc (88.7%) and cadmium (68.2%) by the MSSX system occurred at the pH of 3 and the contact times of 3 and 20min, respectively. Although capability of extraction in the ultrasonically assisted solvent extraction (USAX) system for both metals was higher, the selectivity was lower than that of MSSX system under different conditions especially in high zinc/cadmium ratios. It can be concluded that physical effects (i.e. mixing) inducing at low ultrasonic powers (below 60W) mainly results in increasing solvent extraction rate, while the chemical actions applied at the higher powers have a negative outcome on the extraction rate particularly for cadmium.
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