Conventional Hydrothermal Synthesis of MFI Zeolite in Methanol Solution.

The synthesis of zeolites through more efficient, environmentally friendly, and cost-effective methods was deemed significant in both industrial applications and academic fields. Conventional hydrothermal synthesis strategies have encountered difficulties in producing pure silica MFI zeolite (silicalite-1) under amine-free conditions. This was primarily attributed to the competitive growth of quartz, keatite, or magadiite during the crystallization process. In this work, it was found that the lack of nucleation ability was an important reason for the poor crystallization stability of the methanol solution. Well-crystallized silicalite-1 zeolites with uniform particle sizes were achieved through the cooperative guidance of methanol and seed crystals. Large-scale experiments with silicalite-1 zeolite demonstrated good reproducibility. Combined with the TG-IR and N2 adsorption-desorption results, it was observed that, when an extremely small amount of seed (0.97 wt %) was introduced, methanol could play a role as a crystallization promoter in the hydrothermal synthesis system. Furthermore, a lower alkaline-to-silica ratio and water-to-silica ratio were conducive to the progression of the crystallization process. In summary, this work presented a hydrothermal synthesis strategy for the synthesis of silicalite-1 zeolite in a methanol solution without the need for a large amount of seeds and provided an effective pathway for the low-cost, large-scale production of silicalite-1 zeolite.

[Progress in application of adult endogenous neurogenesis in brain injury repair].

Persistent neurogenesis exists in the subventricular zone (SVZ) of the ventricles and the subgranular zone (SGZ) of the dentate gyrus of the hippocampus in the adult mammalian brain. Adult endogenous neurogenesis not only plays an important role in the normal brain function, but also has important significance in the repair and treatment of brain injury or brain diseases. This article reviews the process of adult endogenous neurogenesis and its application in the repair of traumatic brain injury (TBI) or ischemic stroke, and discusses the strategies of activating adult endogenous neurogenesis to repair brain injury and its practical significance in promoting functional recovery after brain injury.

[Changes in electrophysiological properties of pyramidal neuron in motor cortex during the postnatal early development of mice].

OBJECTIVE: To investigate the electrophysiological properties of pyramidal neurons in mouse motor cortex during the early postnatal development. METHODS: Thirty-six mice were randomly divided into postnatal 1-, 2-, 3-Week and 1-, 2-,3-Month groups (n=6). Membrane properties, action potentials (AP) and spontaneous excitatory postsynaptic currents (sEPSCs) of motor cortex pyramidal neurons were recorded to evaluate the changes in the intrinsic electrophysilogical characteristics by using whole cell patch clamp. Pyramidal neurons and interneurons were distinguished according to the AP firing patterns. RESULTS: Comparing with interneurons, pyramidal neurons exhibited regular spiking (RS) with smaller frequency. During the period of postnatal 1 Week-3 Months, some of the intrinsic membrane properties of motor cortex pyramidal neurons changed. Compared to the 1-Week mice, the resting membrane potential (RMP) of 2-Week decreased significantly (P＜0.01), and the membrane input resistance (Rin) of 1-Month got a hyperpolarization (P＜0.01), and they showed no significant change in the next period, while the membrane capacitance (Cm) showed no significant changes during the whole postnatal development. The AP dynamic properties changed significantly during this period. Compared to the 1-Week mice, the absolute value of the AP threshold and the AP amplitude of the 3-Week increased significantly (P＜0.01), while the spike half width of the 2-Week decreased substantially (P＜0.05), and they showed no significant change in the next period. The sEPSCs frequency and amplitude of 1- Month increased significantly compared to the 1-Week mice(P＜0.01), while during the period of next 1 Month-3 Months, the amplitude and frequency showed no significant change. CONCLUSION: These results suggest that the motor cortex pyramidal neurons have time-specific eletrophysilogical properties during the postnatal development. The electrophysiological properties can be used as a functional index to detect the degree of neurons maturity, and as a marker to distinguish the pyramidal neurons and interneurons.

[Effect of regulating menstruation and promoting pregnancy acupuncture therapy on negative emotion in patients with premature ovarian insufficiency].

OBJECTIVE: To observe the influence of regulating menstruation and promoting pregnancy acupuncture therapy on negative emotions in patients with premature ovarian insufficiency (POI). METHODS: A total of 60 patients with POI were randomly divided into an acupuncture group and a western medication group, 30 cases in each group. The acupuncture group was treated with regulating menstruation and promoting pregnancy acupuncture therapy at Baihui (GV 20), Shenting (GV 24), Guanyuan (CV 4), Sanyinjiao (SP 6), Shenshu (BL 23), Ciliao (BL 32), etc. once a day, 5 times a week for 3 months. The western medication group was treated by oral administration of climen. The drug was given 1 tablet a day for 21 days and was stopped for 1 week as a course. The treatment was required 3 consecutive courses. The self-rating anxiety scale (SAS) score, modified Kupperman index (KI) score, agitated and depressive symptom scores in KI and serum level of follicle stimulating hormone (FSH) before and after treatment were compared between the two groups. RESULTS: After treatment, the SAS scores, KI scores and serum levels of FSH in the two groups and the scores of agitated and depressive symptom in the acupuncture group were lower than those before treatment (P<0.05), and the acupuncture group was lower than the western medication group (P<0.05). CONCLUSION: Regulating menstruation and promoting pregnancy acupuncture therapy can effectively improve the negative emotions of patients with POI and reduce serum level of FSH .