Positive feedback and synchronized bursts in neuronal cultures.

Synchronized bursts (SBs) with complex structures are common in neuronal cultures. Although the phenomenon of SBs has been discovered for a long time, its origin is still unclear. Here, we investigate the properties of these SBs in cultures grown on a multi-electrode array. We find that structures of these SBs are related to the different developmental stages of the cultures and these structures can be modified by changing the magnesium concentration in the culture medium; indicating that synaptic mechanism is involved in the generation of SBs. A model based on short term synaptic plasticity (STSP), recurrent connections and astrocytic recycling of neurotransmitters has been developed successfully to understand the observed structures of SBs in experiments. A phase diagram obtained from this model shows that networks exhibiting SBs are in a complex oscillatory state due to large enough positive feedback provided by synaptic facilitation and recurrent connections. In this model, while STSP controls the fast oscillations (∼ 100 ms) within a SB, the astrocytic recycling determines the slow time scale (∼10 s) of inter-burst intervals. Our study suggests that glia-neuron interactions can be important in the understanding of the complex dynamics of neuronal networks.

Clinical Evaluation of Acupuncture as Treatment for Complications of Cerebrovascular Accidents: A Randomized, Sham-Controlled, Subject- and Assessor-Blind Trial.

Background and Purpose. The effect of acupuncture as treatment for poststroke complications is questionable. We performed a randomized, sham-controlled double-blind study to investigate it. Methods. Patients with first-time acute stroke were randomized to receive 24 sessions of either real or sham acupuncture during an eight-week period. The primary outcome measure was change in National Institute of Health Stroke Scale (NIHSS) score. Secondary outcome measures included changes in Barthel Index (BI), Instrumental Activities of Daily Living (IADL), Hamilton Depression Rating Scale (HAM-D), and Visual Analogue Scale (VAS) for pain scores. Results. Of the 52 patients who were randomized to receive acupuncture (n = 28) or placebo (n = 24), 10 patients in the acupuncture group and 9 patients in the placebo group failed to complete the treatment. In total, 18 patients in the acupuncture group and 15 patients in the control group completed the treatment course. Reduction in pain was significantly greater in the acupuncture group than in the control group (p value = 0.04). There were no significant differences in the other measures between the two groups. Conclusions. Acupuncture provided more effective poststroke pain relief than sham acupuncture treatment. However, acupuncture had no better effect on neurological, functional, and psychological improvement.

PG2 for patients with acute spontaneous intracerebral hemorrhage: a double-blind, randomized, placebo-controlled study.

PG2 is an infusible polysaccharide extracted from Astragalus membranaceus, which is a Chinese herb traditionally used for stroke treatment. We investigated the effect of PG2 on patients with spontaneous acute intracerebral hemorrhage (ICH). A total of 61 patients with acute spontaneous ICH were randomized to either the treatment group (TG, 30 patients), which received 3 doses of PG2 (500 mg, IV) per week for 2 weeks, or the control group (CG, 31 patients), which received PG2 placebo. At 84 days after PG2 administration, the percentage of patients with a good Glasgow outcome scale (GOS 4-5) score in the TG was similar to that in the CG (69.0% vs. 48.4%; p = 0.2). The percentage of good mRS scores (0-2) in the TG was similar to that in the CG (62.1% vs. 45.2%; p = 0.3). In addition, no significant differences were seen when comparing differences in the C-reactive protein, erythrocyte sedimentation rate, interleukin-6 (IL-6), IL-1ß, tumor necrosis factor-α, and S100B levels between baseline and days 4, 7, and 14 after PG2 administration (all p > 0.05). The results are preliminary, necessitating a more thorough assessment.

Chinese Herb Astragalus membranaceus Enhances Recovery of Hemorrhagic Stroke: Double-Blind, Placebo-Controlled, Randomized Study.

We tested the effect of Astragalus membranaceus (AM) on acute hemorrhagic stroke. Seventy-eight patients were randomly assigned to Group A (3 g of AM three times/day for 14 days); or Group B (3 g of placebo herb). A total of 68 patients (Group A 36, Group B 32) completed the trial. The increase of functional independence measure scale score between baseline and week 4 was 24.53 ± 23.40, and between baseline and week 12 was 34.69 ± 28.89, in the Group A was greater than 11.97 ± 11.48 and 23.94 ± 14.8 in the Group B (both P≦0.05). The increase of Glasgow outcome scale score between baseline and week 12 was 0.75 ± 0.77 in the Group A was greater than 0.41 ± 0.50 in the Group B (P < 0.05). The results are preliminary and need a larger study to assess the efficacy of AM after stroke.

Endoscopic surgery for intraventricular hemorrhage (IVH) caused by thalamic hemorrhage: comparisons of endoscopic surgery and external ventricular drainage (EVD) surgery.

BACKGROUND: Intraventricular hemorrhage (IVH) caused by thalamic hemorrhage has high mortality and morbidity. The aim of this study was to investigate the efficacy and the results of endoscopic surgery for the evacuation of IVH caused by thalamic hemorrhage compared with that of external ventricular drainage (EVD) surgery. METHODS: From January 2006 to December 2008, 48 patients with IVH caused by thalamic hemorrhage were enrolled and treated in our department. Patients with IVH caused by thalamic hemorrhage who also resulted in acute hydrocephalus were indicated for surgery; the patients who were included were randomly divided into an EVD group and an endoscopic surgery group. The clinical evaluation data included the Glasgow Coma Scale, length of intensive care unit (ICU) stay, age, intracerebral hemorrhage volume, and severity of IVH. Outcome was measured using the 30-day and 90-day mortality rate, ventriculoperitoneal (VP) shunt dependent rate, and Glasgow Outcome Scale after three months. RESULTS: The clinical features of the 24 patients in each group showed no significant differences in age or Glasgow Coma Scale assessment on admission. There was also no significant difference in intracerebral hemorrhage volume or Graeb score between the endoscopic group and the EVD group. The length of ICU stay was 11 ± 5 days in the endoscopic surgery group and 18 ± 7 days in the EVD group. The endoscopic surgery group had a shorter ICU stay (P = 0.04) compared with the EVD group. The 30-day and 90-day mortality rates were 12.5% and 20.8% in the endoscopic surgery group and 12.5% and 16.6% in the EVD group, respectively. The mean Glasgow Outcome Scale score was 3.08 ± 1.38 in the endoscopic surgery group and 3.33 ± 1.40 in the EVD group. Outcome significantly correlated with initial consciousness level; the severity of IVH did not influence the outcome in all of the cases. There was no significant difference in mortality rate or outcome between the endoscopic group and the EVD group. The VP shunt rates were 47.62% in the endoscopic surgery group and 90.48% in the EVD group. Endoscopic surgery group had a significant lower VP shunt rate (P = 0.002; odds rate = 9.8) compared with the EVD group. CONCLUSIONS: Endoscopic surgery was found to have significantly lower shunt-dependent hydrocephalus, and the ICU stay was shorter compared with EVD surgery. This can decrease the need for permanent VP shunts in patients with IVH caused by thalamic hemorrhage.

A pilot study in acute subarachnoid haemorrhagic patients after aneurysm clipping with complementary therapies of Chinese medicine.

OBJECTIVES: Acute subarachnoid haemorrhage still has high mortality and morbidity despite the use of modern standard treatment. In Taiwan, complementary therapies of Chinese medicine are usually used to treat stroke patients. The aim of this study was to investigate the effect of complementary therapies of Chinese medicine on patients with acute subarachnoid haemorrhage after aneurysm clipping. DESIGN: This study was designed as a pilot study. A total of 32 patients with acute subarachnoid haemorrhage were randomly assigned to either a Chinese herbs extra group (CH) in which the patients were given complementary therapies of Chinese medicine and standard treatment, or a standard treatment only group (ST) in which patients were given standard treatment only. MAIN OUTCOME MEASURES: Glasgow Outcome Scale scores, which were assessed by an evaluator who was blinded to the groups, 3 months after admission, and total admission days including intensive care unit stay days. RESULTS: The average Glasgow Outcome Scale score 3 months after admission was 3.7±1.4 in the CH was greater than 3.0±1.7 in the ST (p=0.041). Average total admission days were 53.9±28.6 (median 61) in the ST longer than 28.1±19.1 (median 20.5) in the CH (p=0.004). CONCLUSION: Traditional Chinese medicine for the treatment of patients with acute subarachnoid haemorrhage is of value because they can increase Glasgow Outcome Scale scores 3 months after admission and also because they can reduce total admission days.

Uncaria rhynchophylla upregulates the expression of MIF and cyclophilin A in kainic acid-induced epilepsy rats: A proteomic analysis.

Uncaria rhynchophylla (Miq) Jack (UR) is a traditional Chinese herb and is used for the treatment of convulsive disorders, including epilepsy. Our previous study has shown that UR, as well as its major component rhynchophylline (RH), has an anticonvulsive effect and this effect is closely related to its scavenging activities of oxygen free radicals. The purpose of the present study was to investigate the effect of (UR) on the expression of proteins using a proteomics analysis in Sprague-Dawley (SD) rats with kainic acid (KA)-induced epileptic seizures. We profiled the differentially expressed proteins on two-dimensional electrophoresis (2-DE) maps derived from the frontal cortex and hippocampus of rat brain tissue 24 hours after KA-induced epileptic seizures. The results indicated that macrophage migration inhibitory factor (MIF) and cyclophilin A were under expressed in frontal cortex by an average of 0.19- and 0.23-fold, respectively. In the frontal cortex, MIF and cyclophilin A were significantly decreased in the KA group and these decreases were confirmed by the Western blots. However, in the hippocampus, only cyclophilin A was significantly decreased in the KA group. In addition, in real-time quantitative PCR (Q-PCR), MIF and cyclophilin A gene expressions were also significantly under expressed in the frontal cortex, and only the cyclophilin A gene was also significantly under expressed in the hippocampus in the KA group. These under expressions of MIF and cyclophilin A could be overcome by the treatment of UR and RH. In conclusion, the under expressions of MIF and cyclophilin A in the frontal cortex and hippocampus in KA-treated rats, which were overcome by both UR and UH treatment, suggesting that both MIF and cyclophilin A at least partly participate in the anticonvulsive effect of UR.