No abstract

Highlights d CA1 over-representation of reward and landmark emerge with distinct time courses d These cells form stable singularities during experiencedependent map consolidation d The over-representation of landmark but not reward is dependent on Shank2

A new set of allergens from Dermatophagoides pteronyssinus and D. farinae (provisionally named DP5 and DF5, respectively) was isolated from the whole culture of mites. The apparent molecular weights of both allergens were shown to be 25,000 on SDS-PAGE under a reducing condition and 27,000 on Sephadex G-75 gel filtration chromatography. Both DP5 and DF5, as well as Der f III, possessed proteolytic activity. The results of substrate specificity and susceptibility to various protease inhibitors of DP5 and DF5 strongly suggested that they belonged to the chymotrypsin-like serine protease family. In sera from 88 mite-allergic patients, specific IgE antibodies to DP5 and/or DF5 were detected in only 41% of the sera by radio-allergosorbent test, while 90% and 93% had specific IgE antibodies to Der p I and/or Der f I and Der p II and/or Der f II, respectively.

A serine protease from mite faecal extract, Dermatophagoides farinae, was purified using DEAE-Sephacel anion exchange chromatography and Superdex 75 pg gel chromatography. The molecular weight of this protease was 34 kD on SDS-PAGE under reducing conditions. The optimal pH and temperature of the protease were 8.0 and 47 degrees C, respectively. In addition, this protease cleaved arginyl or lysyl residue containing substrates selectively and was only inhibited by aprotinin, FUT-175, and soy bean trypsin inhibitor and not by chymostatin, E-64 and iodoacetic acid. These results show that our purified serine protease belongs to the trypsin-type. Purified trypsin-like protease was shown to be allergenic by enzyme-linked immunosorbent assay. Antigenicity of trypsin-like protease was completely different from those of Der f I and Der f II. Both, 20 N-terminal amino acid sequence and amino acid compositions of the purified protease were very similar to those of Der f III. Good similarities were found between trypsin-like protease and Der f III concerning physicochemical properties such as molecular weight on SDS-PAGE and ammonium sulphate solubility. Summarizing the above data, it can be concluded that a trypsin-like protease from mite faecal extract is actually the Der f III allergen and that it may be involved in the digestive process of the mite as it was found not in mite body but in mite faeces.

A cDNA library corresponding to mite protein was screened using anti-Der f II, a major allergen from the house dust mite Dermatophagoides farinae, antibody. Three possible clones were obtained that contained cDNA fragments coding for Der f II, and the nucleotide sequences of the fragments were determined. There were minor differences observed affecting the deduced amino acid sequence among the three cDNA fragments. The amino acid sequence of the purified native Der f II protein could be analyzed to 45 residues from the N-terminus. As a result of comparison, all the three cDNA fragments code for a mature protein with a derived molecular weight of about 14,000. The amino acid sequence was not homologous to any known protein sequences and it contained six cysteine residues and no N-glycosylation sites.

No abstract

Sit-to-stand (STS) motion is an important daily activity, and many post-stroke patients have difficulty performing STS motion. Previous studies found that there are four muscle synergies (synchronized muscle activations) in the STS motion of healthy adults. However, for post-stroke patients, it is unclear whether muscle synergies change and which features primarily reflect motor impairment. Here, we use a machine learning method to demonstrate that temporal features in two muscle synergies that contribute to hip rising and balance maintenance motion reflect the motor impairment of post-stroke patients. Analyzing the muscle synergies of age-matched healthy elderly people (n = 12) and post-stroke patients (n = 33), we found that the same four muscle synergies could account for the muscle activity of post-stroke patients. Also, we were able to distinguish post-stroke patients from healthy people on the basis of the temporal features of these muscle synergies. Furthermore, these temporal features were found to correlate with motor impairment of post-stroke patients. We conclude that poststroke patients can still utilize the same number of muscle synergies as healthy people, but the temporal structure of muscle synergies changes as a result of motor impairment. This could lead to a new rehabilitation strategy for poststroke patients that focuses on activation timing of muscle synergies.

Humans are capable of associating actions with their respective consequences if there is reliable contingency between them. The present study examined the link between the reliability of action consequence and the readiness potential (RP), which is a negative potential observed from about 1–2 s prior to the onset of an action with electroencephalography. In a condition of constant outcome, the participants’ voluntary action always triggered beep sounds; thus, they were able to perceive the contingency between their action and the sound. In contrast, in a condition of inconstant outcome, the participants’ actions only triggered the sound in half the trials. We found that both the early and late RPs were larger in the condition of constant compared to the condition of inconstant outcome. Our results showed that the RPs preceding the voluntary action reflected the reliability of action consequence. In other words, the action-effect contingency enhanced neural activities prior to the action.