A Pilot Study on the Repetitive Transcranial Magnetic Stimulation of Aß and Tau Levels in Rhesus Monkey Cerebrospinal Fluid.

Previous studies have demonstrated that a non-invasive light-flickering regime and auditory tone stimulation could affect Aß and tau metabolism in the brain. As a non-invasive technique, repetitive transcranial magnetic stimulation (rTMS) has been applied for the treatment of neurodegenerative disorders. This study explored the effects of rTMS on Aß and tau levels in rhesus monkey cerebrospinal fluid (CSF). This is a single-blind, self-controlled study. Three different frequencies (low frequency, 1 Hz; high frequencies, 20 Hz and 40 Hz) of rTMS were used to stimulate the bilateral-dorsolateral prefrontal cortex (DLPFC) of the rhesus monkey. A catheterization method was used to collect CSF. All samples were subjected to liquid chip detection to analyze CSF biomarkers (Aß42, Aß42/Aß40, tTau, pTau). CSF biomarker levels changed with time after stimulation by rTMS. After stimulation, the Aß42 level in CSF showed an upward trend at all frequencies (1 Hz, 20 Hz, and 40 Hz), with more significant differences for the high-frequencies (p < 0.05) than for the low frequency. After high-frequency rTMS, the total Tau (tTau) level of CSF immediately increased at the post-rTMS timepoint (p < 0.05) and gradually decreased by 24 h. Moreover, the results showed that the level of phosphorylated Tau (pTau) increased immediately after 40 Hz rTMS (p < 0.05). The ratio of Aß42/Aß40 showed an upward trend at 1 Hz and 20 Hz (p < 0.05). There was no significant difference in the tau levels with low-frequency (1 Hz) stimulation. Thus, high-frequencies (20 Hz and 40 Hz) of rTMS may have positive effects on Aß and tau levels in rhesus monkey CSF, while low-frequency (1 Hz) rTMS can only affect Aß levels.

A preoperative mathematic model for computed tomographic guided microwave ablation treatment of hepatic dome tumors.

PURPOSE: This study sought to prospectively evaluate the feasibility and safety of a preoperative mathematic model for computed tomographic(CT) guided microwave(MW) ablation treatment of hepatic dome tumors. METHODS: This mathematic model was a regular cylinder quantifying appropriate puncture routes from the bottom up. A total of 103 patients with hepatic dome tumors were enrolled and randomly divided into 2 groups based on whether this model was used or not: Group A (using the model; n = 43) versus Group B (not using the model; n = 60). All tumors were treated by CT-guided MW ablation and follow-up contrast CT were reviewed. RESULTS: The average number of times for successful puncture, average ablation time, and incidence of right shoulder pain were less in Group A than Group B (1.4 vs. 2.5, P = 0.001; 8.8 vs. 11.1 minutes, P = 0.003; and 4.7% vs. 20%, P = 0.039). The technical success rate was higher in Group A than Group B (97.7% vs. 85.0%, P = 0.032). There were no significant differences between the two groups in primary and secondary technique efficacy rates (97.7% vs. 88.3%, P = 0.081; 90.0% vs. 72.7%, P = 0.314). No major complications occurred in both groups. CONCLUSION: The mathematic model of regular cylinder is feasible and safe for CT-guided MW ablation in treating hepatic dome tumors.

[Effects of fishing on the marine ecosystem of Beibu Gulf].

By using Ecopath with Ecosim 5.1 software, the Ecosim model of Beibu Gulf marine ecosystem in 1959-1960 was constructed, which included about 20 functional groups such as fishery, marine mammals, sea-birds, sharks, pelagic fishes, demersal fishes, and benthic crustaceans, etc. Through the comparison with the investigation data in 1997-1999, the effects of fishing on the structure and function of Beibu Gulf marine ecosystem were analyzed. The results indicated that with the increasing fishing pressure in past forty years, the ecosystem structure and function shifted drastically, with the biomass of long-lived, high trophic level and piscivorous fishes declined while short-lived and small fishes and benthic invertebrates dominated gradually. The biomass of piscivorous species in 1999 was only 6% of that in 1960, while cephalopods increased 2.7 times or more. The trophic level of the catch declined from 3.2 in 1960 to 2.98 in 1999, which fitted the rule of "fishing down the food web" and suggested that the present exploitation patterns were unsustainable. Based on the data of the 1990s, the changes of the ecosystem under decreasing fishing pressure were predicted. This study validated the feasibility of Ecosim model in predicting the effects of fishing pressure on marine ecosystem.