Mycoplasma pneumoniae and other pathogens in the aetiology of lower respiratory tract infections among Japanese children.

The causes of lower respiratory tract infections in 1544 children attending a Japanese hospital over a period of 7 years were investigated. Both cultivation and two serological techniques were used to detect Mycoplasma pneumoniae whereas viral involvement was investigated only by serology. Pathogens were identified in 52% of 1175 patients with pneumonia and 36% of 369 patients without pneumonia. Mycoplasma pneumoniae infection was specifically diagnosed in 414 (26.8%) of the 1544 patients. Respiratory syncytial virus (RSV) was dominant in children up to 2 years of age. By the age of 3 years, M. pneumoniae was equalling it in incidence and became the main pathogen in older groups. It is suggested that M. pneumoniae may be more important in the 3-6 years age group than hitherto suspected. These observations may influence the choice of antibiotics for treating lower respiratory tract infections in childhood.

Isolation of Mycoplasma pneumoniae from children with lower-respiratory-tract infections.

The prevalence and clinical pictures of Mycoplasma pneumoniae infections among children were studied using culture and serological techniques. The isolation rate was 22% (195 of 885) in pneumonic patients and 11% (66 of 600) in non-pneumonic patients. In patients three years of age or less, M. pneumoniae was isolated at the same rate from febrile and afebrile cases and from wheezy and non-wheezy cases. In older patients, however, M. pneumoniae was frequently isolated from febrile but non-wheezy cases. A peak in the number of the positive isolates was found in patients who were four years old. The peak number of M. pneumoniae infections at age four was confirmed serologically. This peak was in patients who were younger than those previously reported.

Occurrence and distribution of D-cysteinolic acid in fish and shellfish.

1. An unknown compound which is very similar to taurine was detected in the extract of sardine Sardinops melanosticta. 2. It was identified as D-cysteinolic acid: 2-amino-3-hydroxy-1-propanesulfonic acid from instrumental analysis. 3. This may be the first report in which the occurrence of D-cysteinolic acid in fish has been demonstrated. 4. Of 14 species of fish and shellfish examined, the presence of this compound was confirmed in 7 species.

Infusion of fish oil emulsion: effects on platelet aggregation and fatty acid composition in phospholipids of plasma, platelets, and red blood cell membranes in rabbits.

An emulsion of fish oil was manufactured to contain 10 g of fish oil/100 mL. Of this, 3 g were eicosapentaenoic acid (EPA) and 1 g was docosahexaenoic acid (DHA). We administered 100 mL of the emulsion into six rabbits intravenously on days 1, 4, 7, 10, and 13. Blood samples were taken on days 0 and 16. The EPA content in phospholipids of plasma, platelets, and red blood cell (RBC) membranes increased 16, 4, and 5 times, respectively. The DHA content in phospholipids of plasma and RBC membranes increased two times whereas that in platelet phospholipids did not increase significantly. Platelet aggregation induced by collagen (10 micrograms/mL) and ADP (5 microM) was depressed significantly after infusion of the fish oil emulsion. In control experiments with soybean oil emulsion, there were almost no significant changes. Therefore, fish oil emulsion may be beneficial to patients who cannot take n-3 fatty acids orally but need them.

Intake of different eicosapentaenoic acid-containing lipids and fatty acid pattern of plasma lipids in the rats.

The ethyl ester of eicosapentaenoic acid (EPA) is the only pure EPA-containing lipid available in bulk for oral administration. However, there is doubt as to whether EPA ethyl ester can efficiently increase the plasma levels of EPA in comparison with the ability of other kinds of EPA-containing lipids to do so. Therefore, two other kinds of EPA-containing lipids were prepared to study the efficiency of oral administration of those lipids for increasing the EPA content in plasma phospholipids and cholesteryl esters. EPA-containing lipids which were investigated were [A] 1,2,3-trieicosapentaenoyl-glycerol, [B] 2-eicosapentaenoyl-phosphatidylcholine and [C] ethyl ester of EPA. An adjusted amount of lipids [A], [B] and [C] was administered to rats through a gastric tube for 4 days (the first experiment) or for 10 days (the second experiment), and the fatty acid composition of plasma phospholipids and cholesteryl esters was determined. In the first experiment, there were no significant differences in the efficiency for increasing EPA levels in either phospholipids or cholesteryl esters among the lipids. In the second experiment, the EPA levels of both plasma phospholipids and cholesteryl esters of rats administered ethyl ester of EPA were significantly higher than those of rats administered 2-eicosapentaenoyl-phosphatidylcholine. The EPA levels of the rats administered 1,2,3-trieicosapentaenoyl-glycerol were between the levels of the two groups mentioned above, but the differences in the EPA levels were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)

Allergic predisposition among infants with bronchiolitis.

Allergic predisposition among infants with bronchiolitis was examined. The number of infants with serum IgE exceeding mean +1 SD was 31/70 (44.3%). The rate of positive radioallergosorbent test (RAST) scores of 1 or more to mites, egg white, or milk was 31/71 (43.7%) and that of scores over 2 was 11/71 (15.5%). Eosinophils and/or mast cells were found in their nasal smears on several occasions. These results indicated that allergic predisposition may be observed among infants with bronchiolitis.