[Show abstract][Hide abstract] ABSTRACT: A responsive electrical stimulation pattern based on our recently developed novel seizure prediction method was designed to suppress the penicillin-induced epileptic seizures.
Seizures were induced by Penicillin injection at rat cortex. A responsive electrical stimulation system was triggered prior to seizures predicted with phase synchronisation. Rats with induced seizures were stimulated by the electrical pulses at a responsive or 1 Hz periodic pattern of an open system. The effectiveness of stimulation on seizures suppression was assessed by measuring the average number and duration of seizures per hour.
The prediction algorithm reliably identified seizures in real time and triggered the responsive stimulation. This type of electrical stimulation dramatically suppressed seizure activity and the performance was better than the open stimulation system with fewer and shorter seizures.
A responsive electrical stimulation system triggered by the phase synchronisation prediction is able to significantly suppress seizures.
Responsive electrical stimulation could achieve superior treatment performance and reduce power consumption and side effects.
[Show abstract][Hide abstract] ABSTRACT: To investigate the relationship between body mass index and lower limb alignment of patients with knee osteoarthritis.
From July 2008 to June 2010, 78 patients who suffered from severe knee osteoarthritis were treated with total knee replacement, including 17 males and 61 females, ranging from 41 to 85 years old, with an average age of 68.1 years. The Chinese average adult body mass index (BMI) classification standard was used to classify the patients into three groups: normal group, BMI<24.0, including 3 males and 11 females, totalized 14 patients (28 knees), with the mean age of (69.5 +/- 4.7); overweight group, 24.0 < or = BMI<28.0, including 4 males and 25 females, totalized 29 patients (58 knees), with the mean age of (66.4 +/- 7.9) years; and obese group, BMI > or = 28.0, including 10 males and 25 females, totalized 35 patients(70 knees), with the mean age of (69.1 +/- 8.3) years. The limb X-ray film measuring system was used to measure the lower limb alignment at the supine and weight-bearing position.
There were no statistical significances between the normal group and the overweight group in the knee varus angle at the supine and weight-bearing position (P>0.05). However, keen varus angle of the overweight group increased compared with the other two groups at the supine position,and the angle of the weight-bearing position increased nearly 2 degrees, but no statistical significance. There was no statistical significance between supine and weight-bearing position in the three groups of BMI, but the knee varus angle at the supine position was more than the weight -bearing position in the three groups.
The knee varus angle of obese patients with osteoarthritis in the weight-bearing position increases obviously. It indicates that obesity is an important factor increasing the angle of lower limb alignment.
No preview · Article · Nov 2011 · Zhongguo gu shang = China journal of orthopaedics and traumatology
[Show abstract][Hide abstract] ABSTRACT: To investigate the influence of tubulin disassembly on the in vitro metabolism of articular chondrocytes.
Eight New Zealand rabbits aged 2 months were sacrificed by air embolism. The full-thickness cartilages were harvested from both knees under sterile conditions. Then 0.4% pronase and 0.025% II collagenase were used to digest for primary chondrocytes. The cells were cultured for 3 days after attachment and then divided into the control and experimental groups. The control group continued culturing with primary medium and the experimental group with colchicine, a tubulin destructive agent, at a final concentration of 0.1 µmol/L. At Days 1 & 2, the early apoptosis of two cell groups was assayed with phosphatidylserine (Annexin V). At Day 6, the morphological changes of cells were observed by hematoxylin and eosin staining. At Days 3, 6 & 9, the expression levels of type II collagen, proteoglycan and MMP (matrix metalloproteinase)-13 mRNA were measured by real time quantitative fluorescent reverse transcription-polymerase chain reaction (real time RT-PCR). Meanwhile at Days 3, 6 & 9, the cultured supernatant of each group was obtained to detect the contents of type II collagen and proteoglycan by the methods of ELISA (enzyme-linked immunosorbent assay) and Alcian blue.
At Day 2, the early cell apoptosis rate of the experimental group was higher than that of the control group (P < 0.05). At Day 6 post-dosing, the experimental cell morphology was found to be irregular and polygonal. Hyperchromatic nucleus and division phase increased while matrix cell decreased. At Days 3, 6 & 9, the expressions of collagen and proteoglycan mRNA in the experimental group decreased versus those in the control group (P < 0.05). The level of MMP-13 mRNA showed no significant changes in the control group at Day 3. And it significantly increased at Days 6 & 9 (P < 0.01). Meanwhile, type II collagen and glycosaminoglycan were significantly lower in the experimental group at Days 3, 6 & 9 than those in the control group (P < 0.05).
A disassembly of tubulin can induce early apoptosis of chondrocytes. The synthesis and secretion of type II collagen and proteoglycan decrease while there is an elevated expression of MMP-13. The degeneration of cartilage cells and their disrupted synthesis and catabolism result in a serious decline in biological functions.
No preview · Article · Apr 2011 · Zhonghua yi xue za zhi
[Show abstract][Hide abstract] ABSTRACT: Complete and predicable regeneration of complex periodontal structures, which include cementum, periodontal ligament (PDL), and alveolar bone, has been a great challenge for periodontal researchers. It is generally believed that human PDL from the root surface contains stem cells (r-PDLSCs), which can enhance cementum/PDL-like tissues regeneration in vivo. In this work, PDL was found to possess asymmetrically distributed stem cells observed by long-term bromodeoxyuridine (BrdU) labeling. Putative stem cells from human PDL on the alveolar bone surface (a-PDLSCs) were then isolated and characterized. It was shown that a-PDLSCs exhibited strong proliferation capability and expressed high percentages of mesenchymal stem cell markers. Comparatively, a-PDLSCs had higher multilineage differentiation potential than r-PDLSCs with regard to both osteogenic and adipogenic differentiation. Alkaline phosphatase activity and the expression of mineralization-related markers of a-PDLSCs were also higher than those of r-PDLSCs. In vivo, a-PDLSCs could regenerate bone/PDL-like structures and repair critical-size defects created in calvarial bone of NOD/SCID mice. Autologous PDLSC-mediated periodontal regeneration showed that a-PDLSCs could accomplish reconstruction of alveolar bone more perfectly than r-PDLSCs. Our data suggest that PDLSCs may have quite different characteristics depending on locations. a-PDLSCs may take a synergistic effect with r-PDLSCs in periodontal regeneration.
No preview · Article · Dec 2010 · Tissue Engineering Part A
[Show abstract][Hide abstract] ABSTRACT: Abnormal synchronisation change is closely associated with the process of seizure generation. The immediate and accurate detection of the changes in synchronisation may offer advantages in seizure prediction. Thus, we develop a phase synchronisation detection method for this purpose.
An analysis of phase synchronisation based on the complex Gaussian wavelet transform (PSW) was conducted to detect synchronised phases of long-lasting scalp electroencephalograph (EEG) recordings from eight epilepsy patients with intractable temporal lobe epilepsy. Four assessment indicators, namely sensitivity, maximum false prediction rate, seizure occurrence period and seizure prediction horizon were used to assess and compare PSW with the analysis of phase synchronisation, based on the Hilbert transform (PSH) and a random predictor Poisson process.
An obvious decrease was found upon phase synchronisation prior to visual detection of electroencephalograph seizure onset, which was consistent with the EEG mechanism in the ictal events. The results suggest that PSW is the most effective among the three prediction methods.
The results confirm that the analysis of phase synchronisation based on the complex Gaussian wavelet transform can be used for seizure prediction.
Phase synchronisation analysis may be a useful algorithm for clinical application in epileptic prediction.
Full-text · Article · Oct 2010 · Clinical neurophysiology: official journal of the International Federation of Clinical Neurophysiology
[Show abstract][Hide abstract] ABSTRACT: Embryonic stem cells (ESCs) possess an intrinsic self-renewal ability and can differentiate into numerous types of functional tissue cells; however, whether ESCs can differentiate toward the odontogenic lineage is still unknown. In this study, we developed an efficient culture strategy to induce the differentiation of murine ESCs (mESCs) into dental epithelial cells. By culturing mESCs in ameloblasts serum-free conditioned medium (ASF-CM), we could induce their differentiation toward dental epithelial cell lineages; however, similar experiments with the tooth germ cell-conditioned medium (TGC-CM) did not yield effective results. After culturing the cells for 14days in the differentiation-inducing media, the expression of ameloblast-specific proteins such as cytokeratin (CK)14, ameloblastin (AMBN), and amelogenin (AMGN) was markedly higher in mESCs obtained with embryoid body (EB) formation than in mESCs obtained without EB formation. We observed that immunocompromised mice implanted with induced murine EBs (mEBs) showed tissue regenerative capacity and produced odontogenic epithelial-like structures, whereas those implanted with mSCE monolayer cells mainly formed connective tissues. Thus, for the first time, we report that ASF-CM provides a suitable microenvironment for inducing mESC differentiation along the odontogenic epithelial cell lineage. This result has important implications for tooth tissue engineering.
No preview · Article · Mar 2010 · Biochemical and Biophysical Research Communications