Effect of Porosity Parameters and Surface Chemistry on Carbon Dioxide Adsorption in Sulfur-Doped Porous Carbons.

In this work, a series of highly porous sulfur-doped carbons are prepared through physical activation methods by using polythiophene as a precursor. The morphology, structure, and physicochemical properties are revealed by a variety of characterization methods, such as scanning electron microscopy, Raman spectroscopy, X-ray photoelectron spectroscopy, and nitrogen sorption measurement. Their porosity parameters and chemical compositions can be well-tuned by changing the activating agents (steam and carbon dioxide) and reaction temperature. These sulfur-doped porous carbons possess specific surface area of 670-2210 m2 g-1, total pore volume of 0.31-1.26 cm3 g-1, and sulfur content of 0.6-4.9 atom %. The effect of porosity parameters and surface chemistry on carbon dioxide adsorption in sulfur-doped porous carbons is studied in detail. After a careful analysis of carbon dioxide uptake at different temperatures (273 and 293 K), pore volumes from small pore size (less than 1 nm) play an important role in carbon dioxide adsorption at 273 K, whereas surface chemistry is the key factor at a higher adsorption temperature or lower relative pressure. Furthermore, sulfur-doped porous carbons also possess good gas adsorption selectivity and excellent recyclability for regeneration.

[The effects of low-frequency electric stimulus on hippocampal of Effects of low-frequency electric stimulus on hippocampal of α5 subunit of extra synapse GABAA receptor in kainic acid-induced epilepsy rats].

OBJECTIVE: To explore the effects of low-frequency electric stimulus (LFS) on hippocampal of α5 subunit of extrasynaptic GABAA receptor in kainic acid-induced epilepsy rats and explore the possible mechanism of LFS on hippocampus to treat epilepsy. METHODS: A total of 32 male Sprague-Dawley rats were divided randomly into 4 groups:epileptic, pseudo-surgery, LFS treatment and control. The expression of α5 subunit of extrasynaptic GABAA receptor and the association with the curative effects of LFS were evaluated by behavioristics, real-time fluorogenic quantitative polymerase chain reaction (PCR) and Western blot. RESULT: After treatment, the number of seizures in LFS group were significantly lower than that in the epileptic and pseudo-surgery groups (2.88 ± 0.83 vs 8.50 ± 0.93 and 8.88 ± 0.83) (P < 0.01). The results of real-time PCR demonstrated that the expression of mRNA of α5 subunits in LFS treatment group was obviously higher than that in epileptic and pseudo-surgery groups (0.74 ± 0.20 vs 0.30 ± 0.16 and 0.31 ± 0.16) (P < 0.01), but was lower than 1.10 ± 0.23 in control group. Western blot demonstrated that the protein expression of α5 subunits in LFS (0.75 ± 0.09) and control (0.88 ± 0.09) groups were dramatically higher than that in epileptic (0.22 ± 0.08) and pseudo-surgery (0.26 ± 0.08) groups (P < 0.01). CONCLUSION: Low-frequency electric stimulus on hippocampus is effective in controlling epileptic seizures. And the mechanism may be related with the expression level of α5 subunits of extrasynaptic GABAA receptor.

[Expression of α(5) subunit of extrasynaptic GABA(A) receptor in insular-kindled rats].

OBJECTIVE: To explore the expression of α(5) subunit of extrasynaptic GABA(A) receptor in insular electrical kindled rats and analyze its significance. METHODS: A total of 96 male Sprague-Dawley rats were divided randomly into kindled, sham-operated and control groups (n = 32). And each group was further divided into 2 sub-groups at different time points. Kindled group: insular electrical kindled via chronic electrical stimulation; Sham-operated group: electrode implantation without electrical stimulation; CONTROL GROUP: no operation at all. The number of hippocampal neurons was detected by Nissl staining; the mRNA of α(5) subunit of hippocampus by quantitative-polymerase chain reaction (q-PCR); the expression of α(5) subunit of hippocampus by immunohistochemistry. RESULTS: No significant difference existed in the number of hippocampal neurons between epileptic and normal rats (P > 0.05). The mRNA levels of α(5) subunit of hippocampus in the sham-operated and control groups were much higher than that of the kindled group at Day 1 and 7 post-sacrificing (P < 0.01). And the hippocampal expressions of α(5) subunit were much more in the sham-operated and control groups than that of the kindled group at Day 1 and 7 post-sacrificing (P < 0.01). CONCLUSION: The hippocampal expression of α(5) subunit decreases markedly in insular epilepsy. And α(5) subunit may play an important role in the occurrence and development of insular epilepsy.

[Expression of δ subunit of γ-aminobutyric acid A in hippocampus induced by insular-kindled rats].

OBJECTIVE: To explore the expression of δ subunit-containing γ-aminobutyric acid(A) (GABA)(A) receptors in insular electrical kindled rats and analyze the significance of the findings. METHODS: A total of 48 male Sprague-Dawley rats were divided randomly into 3 groups: kindled, sham-operated and control. Kindled group: chronic insular electrical kindled models of rats established by electrical stimulation. Sham-operated group: the same method of the kindled group without electrical stimulation. CONTROL GROUP: without surgery. The number of hippocampal neurons of rat epilepsy, sham-operated and control groups were detected by Nissl staining. The hippocampal expressions of δ subunit of these groups were tested by immunohistochemistry. The mRNA of δ subunit of hippocampus of these groups was detected by quantitative-polymerase chain reaction (q-PCR). RESULTS: The findings of Nissl staining showed that there was no significant difference of the number of hippocampal neurons between epileptic and normal rats (P > 0.05). The findings of q-PCR showed that mRNA of δ subunit of the hippocampus of sham-operated and control groups represented much more than that of kindled group at Day 7 post-kindling (P < 0.01). The findings of immunohistochemistry showed that the hippocampal expression of δ subunit of sham-operated and control groups represented much more than that of kindled group at Day 7 post-kindling (P < 0.01). CONCLUSION: The hippocampal expression of δ subunit-containing GABA(A) receptors decreases in insular epilepsy. It may play an important role in the occurrence and development of insular epilepsy.