An improved technique for repeated gavage administration to rat neonates

ABSTRACT  The technique for gavage administration to rat nurslings was improved to allow determination of the direct effects of chemical substances in the nurslings. Rat neonates were treated with distilled water from postnatal day 1 through 20 using this technique. The viability of neonates during the administration period was comparable to that of untreated neonates. No adverse effects of this technique on the development of neonates were found, and no histological alterations of the esophagus or pharynx. Therefore, we conclude that use of our improved gavage administration method will contribute to ensuring successful neonatal development and thus allowing accurate assessment of the toxicological effects of test compounds on rat nurslings.     

Arrangement of D-periodic collagen fibrils and association of proteoglycans with fibrils in the synovium of the mouse temporomandibular joint

The present study was performed to examine changes in the arrangement of D-periodic collagen fibrils in the synovium of the growing temporomandibular joint in mice. At 1 week of age, the mandibular condyle was undeveloped, and only a few collagen fibrils were recognizable in the subintimal layer of the synovium. At 8 weeks, the mandibular condyle was structurally developed with an increase of collagen fibrils in the synovium; a fully mature condyle was observed at 6 months of age. The close association of proteoglycans with collagen fibrils in the synovium of the growing joint was examined by both conventional and energy-filtering transmission electron microscopy of cupromeronic blue-stained specimens. Proteoglycans were associated with D-periodic collagen fibrils in the short filamentous form in random fashion at 1 week of age, but in a regular pattern with D-periodicity at 6 months. These associations in the synovium could be correlated with the mechanical character of the temporomandibular joint.     

Voxel-based morphometry of human brain with age and cerebrovascular risk factors

The objectives of this study were to evaluate the correlations of the volumes of the gray matter and white matter with age, and the correlations of the tissue probabilities of the gray matter and white matter with age and several cerebrovascular risk factors. We obtained magnetic resonance (MR) images of the brain and clinical information from 769 normal Japanese subjects. We processed the MR images automatically by correcting for inter-individual differences in brain size and shape, and by segmenting the MR images into the gray matter and white matter. Volumetry of the brain revealed a significant negative correlation between the gray matter volume and age, which was not observed between white matter volume and age. Voxel-based morphometry showed that age, systolic blood pressure, and alcohol drinking correlated with the regional tissue probabilities of the gray matter and white matter.     

Expression of Functional Molecules in Non-Hodgkin's Lymphoma

It is well known that non Hodgkin's lymphoma (NHL) cells express various antigens which are normally involved in a variety of functions. In addition, NHL is diverse in its proliferative capacity. To investigate the relation between these factors and the clinical picture, 45 cases of NHL were studied by immunohistochemistry using snap-frozen materials obtained before therapy. Reactivities with 27 monoclonal antibodies were examined and the results were correlated with clinical findings. The expression of surface μ and CAM-1 in B-NHLs and CD25 in T-NHLs were significantly associated with bone marrow involvement. B-NHLs without expression of CD21(B2) and T-NHLs with CD25 were seen more frequently in cases with a LDH value of over 500 units/ml. The positivity rate of Ki-67 on B-NHLs was correlated with serum LDH value, NHL histologic classification, and overall survival. These data indicate that immunophenotyping and determination of the proliferative capacity of NHL are of value not only for confirmation of the histopathologic classification of the tumor but also for assessment of clinical behavior.     

Effects of endurance training on myosin heavy-chain isoforms and enzyme activity in the rat diaphragm

We investigated the effects of endurance training (20 m/min, 60 min/day, 5 days/week) on myosin heavy-chain (MHC) isoforms and succinic dehydrogenase (SDH) activity in rat crural and costal diaphragms, and plantaris muscles. Although the 4-week endurance training produced significant (P<0.05) increases, both in SDH activity and the percentage of isoform HCIIa in the plantaris of the trained rat compared with the sedentary control rat, these alterations did not occur in either the crural or costal diaphragms. After 10 weeks of endurance training, trained animals had significantly (P<0.05) higher SDH activity in the costal diaphragm and the plantaris. Moreover, a significant (P<0.05) decrease occurred in the percentage of HCIIb in the costal diaphragm, and a significant (P<0.01) decrease in the percentage of HCIIb concomitant with a significant (P<0.05) increase of HCIIa resulted in the plantaris. However, the crural diaphragm did not show any significant changes after 10 weeks of endurance training. These results indicate that endurance training induces an alteration in the expression of an MHC phenotype, in addition to causing an increase in oxidative enzyme activity. However, the alterations in response to endurance training are apparently not uniform, varying between regions and/or kinds of muscles.     

Nucleotide sequence of the gene encoding the matrix protein of mumps virus (Miyahara strain)

The nucleotide sequence of the gene encoding the matrix (M) protein of mumps virus (MuV), Miyahara strain, has been determined from several overlapping cDNA clones. The M protein mRNA is 1248 nucleotides in length, exclusive of the poly(A) tail, and codes for a protein of 375 amino acids (Mr41,556). Comparison of the deduced amino acid sequence of the M protein of the Miyahara strain with that of the SBL-1 strain revealed that the M proteins of both strains are highly conserved. A significantly lower rate of nucleotide differences conducive to amino acid differences in the M gene compared with other genes appeared to indicate the importance of the conserved primary structure of the M protein for its function.Requests for reprints should be addressed to Kiyoshi Tanabayashi, Department of Measles Virus, National Institute of Health, 4-7-1 Gakuen, Musashimurayama, Tokyo 190-12, Japan.     

Combination chemotherapy with cyclophosphamide, adriamycin, cisplatin, nimustine(ACNU), and methotrexate (EACAM) in advanced adenocarcinoma of the lung

Twenty-two patients with advanced adenocarcinoma of the lung were treated with the combination chemotherapy "EACAM" consisting of cyclophosphamide (333mg/m2 X 1), adriamycin (27mg/m2 X 1), cisplatin (25mg X 5), nimustine (33mg/m2 X 1), and methotrexate (27mg/m2 X 3). This regimen was repeated once every 4 or 5 weeks. One complete response (CR) and 8 partial responses (PR) were obtained in 21 evaluable patients and the response rate was 42.9%. It has not been possible to calculate the median survival time for all of the evaluable cases, since 13 of them are still alive up to the present time. The side effects observes were as follows: nausea and vomiting (81.8%), alopecia (81.8%), stomatitis (22.7%), leukocytopenia less than 2,000/mm3 (45.5%), and thrombocytopenia less than 5 X 10(4)/mm3 (18.2%). Apart from strong myelosuppression, no severe infection or bleeding tendency was noticed. A mild elevation of serum createnine was observed in one patient, and no patients developed renal insufficiency. The combination chemotherapy "EACAM" is therefore considered to be a very effective and tolerable treatment for adenocarcinoma of the lung.     

A Consideration on the new classification of latest lung ventilators

Concerning the classification of ventilators, Elam (1958), Faireley (1959), and Hunter (1961) reported some simple ones such as pressure limited, volume limited, pressure preset, or volume preset models. Mapleson (1969) also classified them by the generating force or cycling together with the above-mentioned types.The latest ventilators applicable to patients with respiratory failure usually have some cut-off function at high airway pressures as a safety measure. Therefore, all of them belong to the pressure limited type. Some ventilators are of two types such as the time cycled and pressure cycled type.Therefore, we attempted to classify ventilators into four groups, i.e. the time cycled, volume cycled, pressure cycled and selective time-pressure cycled types according to the fundamental mode of ventilator function, the so-called change of cycling from inspiration to expiration. Each group was further divided into subgroups according to preset dials such as respiratory rate, I/E ratio, inspiration time, expiration time, tidal volume, flow rate and airway pressure.By this method, fifty one ventilators on the market in Japan can be classified without overlapping. Although this classification seems complex, it will be of use in selecting ventilators by emphasizing preset dials according to the users needs, ability or both.(Goto Y, Takahashi K, Harada J et al.: A consideration on the new classification of latest lung ventilators. J Anesth 1: 178–182, 1987)