An inactive cathepsin B-like enzyme with a molecular mass of 40 kD was found in a human melanoma culture medium. The inactive form of this enzyme was converted into an active form with a molecular mass of 28 kD by pepsin treatment. This activated cathepsin B-like enzyme had almost the same characteristics regarding molecular size, substrate specificity, dependence on chemical reagents, and Km values as intracellular cathepsin B. Sodium dodecylsulphate polyacrylamide gel electrophoresis followed by electroblotting with an antiserum against cathepsin B yielded inactive cathepsin B-like enzyme fractions which showed two immunoreactive bands with molecular masses of 40 and 28 kD, respectively. On the other hand, alkali treatment of the inactive cathepsin B-like enzyme fractions released a cysteine proteinase inhibitor with a molecular mass of 12 kD. These data suggest that these inactive cathepsin B-like enzymes in melanoma culture medium are present not only in the precursor form, but that they are also present as enzyme-inhibitor complexes, both of which can be activated enzymatically in vitro.

Cathepsin B↗

PubMedDate not supplied

Alpha-1-antichymotrypsin is not associated with the increased frequency of apolipoprotein-E-epsilon-4 allele in elderly non-demented leprosy patients.

In our previous study, elderly leprosy patients showed a low prevalence of senile dementia of the Alzheimer type, but the frequency of apolipoprotein E (APO-E) epsilon 4 was elevated in non-demented elderly leprosy patients. Recent study has shown that Alzheimer's disease risk associated with APO-E epsilon 4 is significantly increased by the alpha 1-antichymotrypsin (ACT) genotype AA. Therefore we examined an association between ACT polymorphism and the APO-E epsilon 4 allele in 350 leprosy patients. None of our data showed an association of ACT genotype and APO-E epsilon 4 allele in leprosy patients. The allelic frequencies of the ACT gene did not differ even between demented patients with leprosy and age-matched controls. Our present data suggest that ACT polymorphism is not associated with the increased frequency of APO-E epsilon 4 in leprosy patients.

Adult↗

PubMedDate not supplied

Secretory IgA in saliva and academic stress.

Several reports have proposed that the concentration of secretory immunoglobulin A (S-IgA) in saliva is an indicator of psychological stress. With this in mind, we decided to examine it in 10 second year medical student volunteers at Kawasaki Medical School course between May 4 and July 13, 2000 and discussed the relationship between S-IbA and the stress from academic examinations. Saliva was collected three times (on rising, at forenoon, and at bedtime) every Thursday. During this period, sporadic academic examinations were held twice and term end examination occurred during the last two weeks. Results showed the concentration of S-IgA significantly higher at the on rising time-point than at the other two time-points. There was also a tendency for the S-IgA level in saliva to be higher on the day before academic examinations and during them and lower on the days between these examinations. In addition, daily variations in the S-IgA concentration sometimes seemed to be disturbed by other academic stress. Therefore it may be possible to use this measurement to monitor psychological stress in students and workers.

Adult↗

PubMedDate not supplied

Effect of the nitrosourea anti-tumor chemotherapeutical agent MCNU on five human myeloma cell lines.

We investigated the effects of MCNU (methyl-6)3-(2-chloroethyl)-3-nitrosoureido)-6-deoxy- alpha-D-glucopyranoside), a nitrosourea anti-tumor agent developed in Japan, on cell growth and differentiation in five human myeloma cell lines and compared it with relative expression levels of MDR-1 gene. Although 10 microg/ml of MCNU inhibited cell growth in KMM-1 and KMS-5 lines, other three cell lines required 20-40 microg/ml of MCNU to obtain similar growth inhibition. Accumulation up to the G2 phase of the cell cycle was observed in KMM-1 and KMS-5 lines and the cloning efficiency of KMS-5 cells was reduced by MCNU. On the other hand, expression of surface markers on these lines was not altered remarkably except for increased expression of CD38 on KMS-5 cells. However, the effect of MCNU on these cell lines did not correlate to relative expression levels of MDR-1 gene analyzed by RT-PCR. MCNU may inhibit the growth of myeloma cells by the accumulation of these cells up to the G2 phase, but may not affect their differentiation.

Antineoplastic Agents↗

PubMedDate not supplied

Some physiological aspects of the basal ganglia. Excitation of the neurons of the globus pallidus by the brain stem structures.

The caudate efferent fibers to the globus pallidus are inhibitory in nature. The pallidothalamic fibers are also inhibitory, exerting monosynaptic IPSPs on the thalamic cells located anteroventrally to the ventrolateral nucleus. Therefore, these two inhibitory neuronal circuits make a double inhibitory chain. To operate the inhibitory circuit, excitatory input to the pallidum is necessary. Stimulation of the ipsilateral brain stem including lemniscus medialis, mesencephalic reticular formation and some other structures, produces short latency excitation of the pallidal cells.

Animals↗

PubMedDate not supplied

The cell concentration method using acetylcysteine for sputum cytology.

In order to improve the results of cytologic diagnosis of pulmonary carcinoma, a technique for concentrating cells from sputum using acetylcysteine was developed. Using the same sputum specimens, the rate of positive cytologic diagnosis of pulmonary carcinoma by this method was increased by 22.6% over the level achieved by the direct smear method. This cell concentration method improved the rate of positive diagnosis in peripheral type pulmonary carcinoma and particularly in adenocarcinoma. The cell concentration method using acetylcysteine shows great promise in the cytologic diagnosis of sputum specimens.

Acetylcysteine↗