Comparison of articular cartilage repair by autologous chondrocytes with and without in vitro cultivation.

OBJECTIVE: autologous chondrocyte implantation usually requires in vitro cell expansion before implantation. We compared the efficacy of cartilage regeneration by in vitro-expanded chondrocytes at high density and freshly harvested chondrocytes at low density. DESIGN: surgically created osteochondral defects at weight-bearing surface of femoral condyles of domestic pigs were repaired by biphasic cylindrical porous plugs of DL-poly-lactide-co-glycolide and beta-tricalcium phosphate. Plugs were seeded with autologous chondrocytes in its chondral phase, and press-fit to defects. Seeded cells were (1) in vitro-expanded chondrocytes harvested from stifle joint 3 weeks before implantation and (2) freshly harvested chondrocytes from recipient knee. Seeding densities were 70 x 10(6) and 7 x 10(6) cells/mL, respectively. Cell-free plugs served as control and defects remained untreated as null control. Outcome was examined at 6 months with International Cartilage Repair Society Scale. RESULTS: the two experimental groups were repaired by hyaline cartilage with collagen type II and Safranin-O. Tissue in control group was primarily fibrocartilage. No regeneration was found in null control. Experimental groups had higher mean International Cartilage Repair Society scores than control in surface, matrix, and cell distribution, but were comparable with control in cell viability, subchondral bone, and mineralization. No significant difference existed between two experimental groups in any of the six categories. Uni-axial indentation test revealed similar creeping stress-relaxation property as native cartilage on experimental, but not control, specimen. CONCLUSIONS: cartilage could regenerate in both experimental models, in comparable quality. Culture of chondrocytes before implantation is not necessary.

Normal pressure hydrocephalus: cerebral hemodynamic, metabolism measurement, discharge score, and long-term outcome.

BACKGROUND: Regional CBF study has been reported effective in the selection of patient with NPH. However, controversial outcome had been reported. We sought to determine if the combination of rCBF measurement, cerebrovascular reactivity, and regional metabolism were positive predictors of shunt responsiveness in NPH syndrome. METHODS: Twenty-eight patients with clinical diagnosis of NPH were enrolled to study their rCBF in CSWM before and after the ACT challenge test, the regional CSWM metabolism by MRSI, and the clinical grading by the CSRIH defined by the Ministry of Health and Welfare of Japan in 1996. All the patients received VP shunting procedure by the same neurosurgical team. The pre- and postoperative clinical conditions were recorded. A patient was considered as "responder" when the patient's CSRIH total score decreased by one or more points. Patients have been followed for a median duration of 40.6 months (range, 28-67 months) with Karnofsky performance scale. RESULTS: Twenty-three responders had significant improvement after VP shunting in clinical grading; 5 nonresponders were stationary after VP shunting. During the 3 years of follow-up, 5 of the 28 patients died, the other 6 were lost to follow-up (including telephone contact), and 3 had progressive deterioration. The prechallenge rCBF decreased in all the 28 subjects. In the 23 responders, the rCBF after challenge were greater than 20 mL/min per 100 g (P=.008), had a significantly better CRC in the anterior CSWM than the nonresponders (1.40 vs 1.06), and had normal NAA/Cre ratio in the anterior, middle, and posterior CSWM in MRSI study. In those nonresponders, the NAA/Cre ratio was less than 0.8 in at least 2 regions of CSWM, and in 23 patients with symptoms other than ataxia (dementia, incontinence), the NAA/Cre ratio was less than 1.5 at frontal CSWM area. Discharge CSRIH scale was well correlated with CRC (P<.03), the average ACT challenge CBF (P<.005), and the average rCBF (P<.02). There was a statistically significant correlation between discharge CSRIH scale and follow-up performance at 3 months (P=.017), 2 years (P=.018), and 3 years (P=.038). CONCLUSION: Measurement of cerebrovascular hemodynamic and regional metabolism can be a good predictor of outcome after shunting in patients with NPH. Magnetic resonance spectroscopic imaging at frontal CSWM has good correlation with clinical symptoms. After VP shunting procedure, the discharge CSRIH scale is a good predictor of long-term outcome of patients with NPH.

Lateral modulation of BOLD activation in unstimulated regions of the human visual cortex.

After staring at a blank region surrounded by a dynamic background for a few seconds, observers report a twinkle aftereffect in the unstimulated blank region. The significance of this twinkle aftereffect is that it occurs at a location that received no stimulation, and therefore reflects a rebound from lateral inhibition within the dynamic processing system. To study this inhibitory rebound effect, the blood oxygenation level dependent (BOLD) activation in the visual cortex was measured while the observers were viewing a flickering pin-wheel pattern alternating with a blank test. Retinotopic regions corresponding to the inter-wedge regions in the pin-wheel pattern showed activation negatively correlated with the test sequence. While the BOLD activation in the visual cortex is generally considered to be retinotopically driven by the visual stimuli, we were able to show a sustained negative activation in the unstimulated regions, with properties that correspond to those of the inhibitory rebound of the perceived aftereffect.

Echinacoside rescues the SHSY5Y neuronal cells from TNFalpha-induced apoptosis.

We investigated the neuroprotective effect of echinacoside, one of the phenylethanoids isolated from the stems of Cistanches salsa, a Chinese herbal medicine, on tumor necrosis factor-alpha (TNFalpha)-induced apoptosis in human neuroblastoma (SHSY5Y) cells. Treatment of cultured SHSY5Y cells with TNFalpha 100 ng ml(-1) for 36 h stimulated apoptosis, as demonstrated by typical morphological changes, cell viability, DNA laddering, annexin-V binding, intracellular reactive oxygen species, mitochondrial membrane potential and caspase-3 activity. However, simultaneous treatment with echinacoside (1, 10 or 100 microg ml(-1)) attenuated the TNFalpha-mediated apoptosis. The antiapoptotic action of echinacoside was partially dependent on antioxidative stress effects, maintenance of mitochondria function, inhibition of caspase-3 activity and was also associated with increasing the expression of the antiapoptotic protein Bcl2. Thus, echinacoside has the neuroprotective capacity to antagonize TNFalpha-induced apoptosis in SHSY5Y cells and may be useful in treating some neurodegenerative diseases.

Comparison of histidine-tryptophan-ketoglutarate and Euro-Collins solutions for lung preservation using the minipig in situ warm ischemia model.

BACKGROUND AND PURPOSE: Reperfusion injury remains a common problem in lung transplantation. This study compared the effect of lung preservation with histidine-tryptophan-ketoglutarate (HTK), a relatively low potassium solution, and Euro-Collins (EC) solution by using a minipig in situ model of warm ischemia. METHODS: The left lungs of 5 minipigs were selectively flushed with EC solution. HTK was used for flush perfusion in 6 other minipigs. After 60 minutes of warm ischemia, the left lungs were reperfused. Hemodynamics, aerodynamics, and arterial blood gas were measured after the blood flow and ventilation of the contralateral lungs were temporally blocked. Bronchoalveolar lavage fluid (BALF) analysis, lung wet-to-dry weight ratio (W/D ratio) and histological analysis were done before perfusion (right lung) and 2 hours after reperfusion (left lung). RESULTS: This in situ model of warm ischemia induced significantly increased pulmonary arterial pressure, pulmonary vascular resistance, BALF albumin contents and neutrophil counts, histological injury score, lung W/D ratio and tissue myeloperoxidase assay. The HTK perfusion group had a significantly lower degree of lung injury than the EC perfusion group. CONCLUSIONS: Lung preservation with HTK solution resulted in better lung function after reperfusion than preservation by EC solution in this minipig model.