The effects of bone marrow stromal cells (BMSCs) on the repair of injured spinal cord and on the behavioral improvement were studied in the rat. The spinal cord was injured by contusion using a weight-drop at the level of T8-9, and the BMSCs from the bone marrow of the same strain were infused into the cerebrospinal fluid (CSF) through the 4th ventricle. BMSCs were conveyed through the CSF to the spinal cord, where most BMSCs attached to the spinal surface although a few invaded the lesion. The BBB score was higher, and the cavity volume was smaller in the rats with transplantation than in the control rats. Transplanted cells gradually decreased in number and disappeared from the spinal cord 3 weeks after injection. The medium supplemented by CSF (250 microl in 3 ml medium) harvested from the rats in which BMSCs had been injected 2 days previously promoted the neurosphere cells to adhere to the culture dish and to spread into the periphery. These results suggest that BMSCs can exert effects by producing some trophic factors into the CSF or by contacting with host spinal tissues on the reduction of cavities and on the improvement of behavioral function in the rat. Considering that BMSCs can be used for autologous transplantation, and that the CSF infusion of transplants imposes a minimal burden on patients, the results of the present study are important and promising for the clinical use of BMSCs in spinal cord injury treatment.

␤-D-Glucan is one of the major structural components of fungi, and it seems that it can be detected by the fractionated (133)-␤-D-glucan-sensitive component from a Limulus lysate, factor G. We evaluated the concentration of (133)-␤-D-glucan by using factor G and other fungal antigens in 24 patients with clinical evidence of mycosis and 36 healthy subjects. The mean concentration of (133)-␤-D-glucan in the plasma of the healthy subjects was found to be 2.7 ؎ 1.9 pg/ml (range, <6.9 pg/ml), and it was found to be substantially higher in all 11 patients with candidemia (mean, 2,207.4 pg/ml; range, 325.4 to 8,449.0 pg/ml). Eight of those 11 patients with candidemia (73%) were positive for the Cand-Tec heat-labile candida antigen and only 3 patients (27%) were positive for mannan antigen. Three patients with invasive pulmonary aspergillosis were positive for galactomannan and had, in addition, high concentrations of (133)-␤-D-glucan (mean, 323.3 pg/ml; range, 27.0 to 894.0 pg/ml). All 10 patients with cryptococcosis (including 2 patients with probable cryptococcosis) were positive for cryptococcal antigen by the Eiken latex test; however, (133)-␤-D-glucan levels were not elevated in these patients (mean, 7.0 pg/ml; range, <16.5 pg/ml). Our results indicated that (133)-␤-D-glucan levels are elevated in patients with candidiasis and aspergillosis but not in those with cryptococcosis.

We have developed an alginate gel crosslinked with covalent bonds for regeneration of dermis, nerve, and bone. Recently, a novel matrix (H/A gel) which consists of heparin and alginate covalently crosslinked with ethylenediamine, was designed. It can stabilize and release biologically active basic fibroblast growth factor (bFGF) for 1 month, which is one of the heparin-binding growth factors. In the present report, we examined the effect of this novel H/A gel on nerve regeneration in the rat sciatic nerve. In this study, regenerated axons in H/A gel with bFGF grew faster than in ordinary alginate gel with bFGF in the early stage. Myelinated fibers showed a tendency to increase in diameter toward the normal size in the later stage. Nerve bundles in the implantation exhibited minimal fibrosis and good vascularization. H/A gel with bFGF exhibited better-developed vascularization than ordinary alginate gel with bFGF. These findings suggested that H/A gel with bFGF could serve not only as an efficient cellular scaffold, but also as a stabilizing matrix for bFGF for peripheral nerve regeneration.

No abstract

Neurons in the cerebral cortex are not homogeneous. However, neuronal types have been ignored in most previous work studying neuronal processes in behaving monkeys. We propose a new method to identify neuronal types in extracellular recording studies of behaving monkeys. We classified neurons as either bursting or non-bursting, and then classified the bursting neurons into three types: (i) neurons displaying a burst of many spikes (maximum number of spikes within a burst; NSB max > or = 8) at a high discharge rate (maximum interspike interval; ISI max < 5 ms); (ii) neurons displaying a burst of fewer spikes (NSB max < or = 5) at a high discharge rate (ISI max < 5 ms); and (iii) neurons displaying a burst of a few spikes (NSB max < or = 7) at relatively long ISIs (ISI max > 5 ms). We found that the discharge patterns of the four groups corresponded to those of regular spiking (RS), fast spiking (FS), fast rhythmic bursting (FRB) and intrinsic bursting (IB) neurons demonstrated in intracellular recording studies using in vitro slice preparations, respectively. In addition, we examined correlations with the task events for neurons recorded in the frontal eye field and neuronal interactions for pairs of neurons recorded simultaneously from a single electrode. We found that they were substantially different between RS and FS types. These results suggest that neurons in the frontal cortex of behaving monkeys can be classified into four types based on their discharge patterns, and that these four types contribute differentially to cortical operations.