We investigated the distribution of oral α-streptococci with inhibitory activity against pathogens, which compose an oral defense mechanism.
Detection rate of α-streptococci with inhibitory activity against S. pyogenes and S. aureus derived from the tonsil was higher than in other portions, the tongue, cheek, gingiva, or saliva. It has suggested that tonsillar bacterial flora are mainly a defense mechanism.
The oral flora in healthy smokers was compared with healthy non-smokers to investigate the influence of tobacco on oral bacterial flora.
The results showed that the detection rate of S. aureus in smokers was higher while that of α-streptococci with inhibitory activity against S. aureus was lower. However, the detection rate of α-streptococci with inhibitory activity against S. pyogenes in smokers was as high as in non-smokers.
It is suggested that it was easy for S. aureus to adhere to the oral mucosa in smokers, and was considered to influence the strain which produces β-lactamase for medical treatment. We investigated the influence of gargling on oral bacterial flora by comparing the amount of bacteria before and after gragling with popidine-iodine gargle and saline solution.
It was shown that α-streptococci, a main component of normal oral flora were decreased after gargling in both smokers and non-smokers.
Furthermore, it was shown that group A Streptococcus was not decreased after gargling, and it was concluded that use of gargle medicinal mouth wash in bacillus carriers should be studied further.

View full abstract

Forestry workers in Saitama Prefecture are in high occupational risk to Lyme borreliosis transmitted by ticks. We surveyed the incidence of tick bites and the prevalence of antibodies against Borrelia burgdorferi in 80 forestry workers. ELISA with the antigen from B. burgdorferi sensu stricto B31 as well as Borrelia garinii HP3 and Borrelia japonica HO14 isolated in Japan was used for the detection of antibodies. Antibody-positive cases against B31, HP3 and HO14 was 3.8, 23.8 and 13.8%, respectively. Antibody-positive cases by ELISA were subjected to Western blotting with the antigens from three borrelias. Finally, 20.0% of the workers were antibody positive by specific antibodies, anti-OspA antibody. The correlation between ELISA and Western blotting was better when HP3 was used as an antigen. One out of 30 normal control individuals was positive in ELISA with HP3 antigen, but negative in Western blotting.
Thirty percent of the workers had a history of tick bites, and these cass had no characteristic symptoms of Lyme borreliosis. However, the rate of tick bites in antibody-positive cases was significantly higher than that in antibody-negative cases. These results suggested that the forestry workers in Saitama are very likely to be infected with Lyme borreliosis transmitted by ticks.

View full abstract

Basic and clinical evaluation of lysis centrifugation using Isolator 10 was performed and compared with culture bottle methods. Blood, which was inoculated with C. albicans, C. tropicalis or C. parapsilosis, was cultured using lysis centrifugation or culture bottle method. The culture duration of C. albicans and C. parapsilosis by lysis centrifugation was shorter than that by the culture bottle (BHI release).
C. albicans, C. parapsilosis and C. tropicalis became culture-positive within 1 or 2 days after culture by lysis centrifugation. C. albicans and C. parapsilosis became positive 4 days and C. tropicalis 6-8 days after culture by the culture bottle (BHI super).
Clinical evaluation of both blood culture method as performed from April 1990 to March 1994. Sixty samples (4.4%) were positive out of 1370 samples. Twenty eight samples (7.2%) were positive out of 389 samples, which were examined by both methods.
Twenty two samples were positive by both methods and the rest of the 6 samples was positive only by Lysis centrifugation.

View full abstract

We have previously reported that the hot water of 17 (42.5%) out of 40 thermal baths were contaminated with legionellae. Our recent investigation revealed that legionellae inhabited 39 (66.1%) of the 59 thermal bath water, and their viable counts were at the level of 10⁴ CFU/100 ml in 5 baths and 10⁵ CFU/100 ml in another 5. Accordingly, the bactericidal effects of free chlorine on 102 strains of 22 Legionella species were tested, in order to find a method of controlling legionellae in thermal bath water. The test strains were the type strains of 22 species, 35 strains of 4 species from patients with Legionella pneumonia in Japan, and 45 strains of 4 species from thermal bath water. Viable cells of all 102 strains suspended at the concentration of 10⁵ CFU/100 ml in sodium hypochloride solution with 0.4 mg/1 free chlorine became undetectable within 15 min.

View full abstract

Polymerase chain reaction (PCR) has been extensively used for diagnosis recently because of its very high sensitivity and specificity. We studied the applicability of PCR to the early diagnosis of toxoplasmosis in a murine model orally infected with Toxoplasma gondii (S-273). PCR was performed using EH24 and HE27 primers synthesized by the phosphoramidite method. Mice blood and brains collected on various post infection days (PID) were analysed by PCR (35 cycles). A portion of the brain tissue from each mouse was examined microscopically for the presence of parasite cysts. Blood and brain PCR were positive on the 9th and 12th day post-infection (DPI). Toxoplasma cysts in brain tissue appeared only on the 18th PID. The results showed that Toxoplsma parasites can be detected earlier in the blood than in the brain during primary infection, indicating that blood PCR is the more useful procedure.

View full abstract

Changes of titers of acquired hepatitis B surface (HBs) antibodies against HB vaccine were investigated by measuring them again after a long lapse of time. Ten jig of the recombinant HB vaccine was intramuscularly injected respectively to the staff of the authors' hospital three times. Four weeks after a full course of the vaccination 185 persons could acquire antibodies, whose titers were 2.0 or more in cut off index (C. I.) by radioimmunoassay (RIA). Of these members titers of antibodies of 48 subjects could be remeasured for the first time 38 months after the meaurement of the titers in the 4th week after a full course of the vaccination. Four weeks after the last vaccination 7 persons were high responders whose titers of antibodies were 50 or more in C. I., 29 were medium responders with their titers from 49 to 10, and 12 were low responders having titers of less than 10. However, 38 months after the course the titers of those responders decreased so much that nobody remained highly responders, 22 were low responders, and the remaining 22 turned to be negative again with titers less than 2.0. Supposing that the titer of antibody enough to protect the infection of HB virus is 10 or more in C. I., 32 of 36 persons neededbooster shots 38 months later because their titers dwindled down to less than 10. While in 24 members, who had their titers of antibodies measured for the first time 16 months after the measurement of the titers in the 4th week after a full course of the vaccination, 8 members had titers which changed to be less than 10. Twelve of the 32 subjects, whose titers were less than 10 38 months later, recieved a booster injection, respectively. As a result, they obtained good responses; that is, all their titers returned to 10 or more, and the average titere was more than that 4 weeks after the planned course of the vaccination. It was confirmed that the titer of an acquired antibody should be measured repeatedly, and a booster shot is indispensable to keep the antibody high enough to protect from the infection, for the acquired HBs antibody has a tendency to reduce rapidly.

View full abstract

Clinical features in Vibrio infection are generally represented by gastrointestinal involvements such as food poisoning, and its prognosis is usually good. However, Vibrio vulnificus infection not uncommonly causes serious problems including sepsis, necrotizing fasciitis of the extremeties, and other conditions, sometimes resulting in fatal outcome. In the present study, we analyzed clinical microbiological aspects of five cases with V. vulnificus infection.
All the strains of V. vulnificus isolated in five patients are oxydase-positive Gram negative rods presenting comma-like configuration, which were yielded on TCBS agar forming green colonies; they were grayish-white in color and viscous in texture on 5% sheep blood agar. identification of bacteria were done using VITEK AMS (BioMerieux). Piperacillin and thirdgeneration cephalosporines were found to have bactericidal activities against these strains.
All five cases we experienced have primary ailments, and three cases out of the five had taken perishable sea-food before showing disease symptoms. V. vulnificus has two infection channels; one is external wound and the other is oral intake. The latter is said that it may become serious. This has a rather short period from the starting the symptoms to death, and there is high death rate. For life-saving, it is inevitably necessary to dose an effective antibacterial medicine in the early stage. If we suspect this bacteria in the test laboratory, it is important to report this to the clinical doctor. In other words, this is one of the bacteria that needs prompt treatment and further microbiology testing.

View full abstract

A protocol based on the polymerase chain reaction (PCR) is the most sensitive method for detecting mycobacteria in clinical samples. However, few studies have assessed the usefulness of this method in the diagnosis of tuberculous effusion. We developed a highly sensitive and specific nested PCR method, that amplifies the bovine tuberculous MPB70 gene and the mycobacterial 16S rRNA gene for use in detecting Mycobacterium tuberculosis (M. tuberculosis) and mycobacteria, respectively, in clinical samples. We determined the sensitivity of this method for detecting mycobacteria in samples containing known amounts of mycobacterial DNA and in DNA extracted from pleural effusions obtained from 10 patients with pulmonary tuberculosis in whom standard microbiological techniques had detected mycobacteria in sputum but not in pleural effusion. The nested PCR method for the bovine tuberculous MPB70 gene and the mycobacterial 16S RNA gene was able to detect M. tuberculosis and mycobacterial genomes only if there were at least 2 copies per sample. Positive results for M. tuberculosis and the mycobacterial genomes were obtained by nested PCR in 2 of 10 and in 3 of 10 samples of pleural fluid, respectively but no mycobacteria were detected in malignant effusions obtained from 9 patients with lung cancer. The nested PCR method represents a rapid means for detecting mycobacteria in some pleural effusions previously found to be negative by cluture. We speculate that the reaction of the host against mycobacteria is more important than the mycobacteria themselves in the pathogenesis of pleural effusion in which mycobacteria are not detected.

View full abstract

Using a mouse experimental UTI (urinary tract infection) model, a study was conducted to find the pathogenicity of various serovars of E. faecalis. On the basis of studies employing serovar-specific factor sera prepared with E. faecalis type strains, serovar 2, 3, 4 and 10 strains showed a high incidence of involvement in pyelonephritis: 90.3%, 85.7%, 85% and 73.3%. Serovar 1, 6 and 7 strains each showed a 63.6% incidence of involvement in pyelonephritis, indicating that they have a moderate pathogenicity. The pathogenicity of the other serovar strains was not very strong, with a low incidence of 40-59.1%.
These results were thus in good agreement with the findings of the study using the mouse experimental UTI model infected with clinical isolates.
Serotyping was performed of E. faecalis clinical isolates obtained from patients with pyelonephritis or urosepsis. Serovars 2 and 4 comprised 75.1% of those isolates.
It was surmised that E. faecalis serovars 2 and 4 tend to have strong pathogenicity. Thus, there were quite a few differences in pathogenicity of E. faecalis according to each kind of serovar.

View full abstract

Serotyping was conducted of E. faecalis strains isolated from various clinical specimens, and the distribution of the serovars was investigated.
To date, 21 serovars of E. faecalis have been identified.
The most common serovars in Japanese 770 strains were types 2 (30.6%), 7 (13.9%), 1 (12.2%) and 4 (6.9%), and these four serovars accounted for 63.6% of the total strains. The most common serovars in USA 200 strains were types 1 (22.5%), 4 (14.5%) and 2 (14.0%). The most common serovars in UK 65 strains were types 2 (24.6%), 4 (13.8%) and 9 (7.7%).
The distribution of E. faecalis serovars differ as a function of the country of origin.
Next, serological classification was performed for E. faecalis strains isolated from various Japanese clinical specimens. For the strains obtained from the urine, the most common serovars were types 2 (32.7%) and 7 (14.6%). Similarly, the most common serovars of the strains isolated from the various other clinical specimens were as follows: types 7 (35.0%) and 2 (15.0%) from pus; types 7 (44.4%) and 2 (33.3%) from sputum; types 2 (22.3%) and 1 (13.1%) from blood; and types 2 (34.9%) and 1 (27.9%) from the vaginal smear. It had no definite pattern for the distribution of serovars.
The distribution of serovars varied in accordance with isolated years.
Accordingly, the data obtained in these studies revealed that the distributions of E. faecalis serovars differ as a function of the geographical area of origin, the clinical specimen of origin and the year of origin.
This approach is useful for serological classification of E. faecalis strains, and it is thought that it will be useful for epidemiological studies of this bacterium.

View full abstract

Mucoid Stenotrophomonas maltophilia was isolated from the sputum of 2 women. Case 1 which we reported recently was primary pneumonia caused by S. maltophilia. However, in Case 2, mucoid S. maltophilia reprsented part of the transient flora. Interestingly, colonization of mucoid Pseudomonas aeruginosa on respiratory tract occurred in both cases after mucoid S. maltophilia was isolated from their sputum.

View full abstract

A case of a HIV infected 61-year-old bisexial male with dilated cardiomyopathy (DCM) is reported. The death was originally recorded as from undertermined causes, but on autopsy, his heart showed left ventricular dilatation macroscopically, variety in size and vacuolation of cardiomyocyte, partial deciduation of cardiac muscle and diffuse perivascular fibrosis microscopically. These findings were compatible with DCM which was compounded by excessive weight loss. The further data indicated that the etiology of DCM in this case was directly related to the HIV infection.

View full abstract

We reported a 53-year-old female who was admitted due to partial loss of consciousness. She had been diagnosed as old pulmonary tuberculosis and diabetes mellitus. She was diagnosed as diabetic keto-acidosis on admission. We isolated Escherichia coli in the blood, transtracheal aspiration (TTA) and from the urine. We have experienced 6 cases where the same bacteria was isolated from the blood and TTA at the same time.
In all 6 cases, we have found single bacteria in the blood and a few other bacteria in TTA. Blood culture is the most certain method to detect the origin of infectious diseases. But the compromised host, as in this case, has multifocal infections in many cases. In order to understand the pathological aspects of the infection, we must obtain many kinds of samples and as many as possible.

View full abstract

This 35-year-old housewife was initially treated with vincrisitne, prednisolone and Lasparaginase for acute lymphoblastic leukemia (ALL, L1 by FAB classification) in 1988 and entered into complete remission. Ten months later she underwent bone marrow transplantation (BMT) from her HLA-identical and MLC-negative sister. The conditioning regimens consisted of busulfan 4 mg/kg/day for 4 days orally and cyclophosphamide 60 mg/kg/day for 2 days intravenously followed by cyclosporine and prednisolone for graft-versus-host disease prophylaxis.
Fifty days after BMT, she suffered interstitial pneumonitis and a gastric ulcer, and was treated with a high dose of methylprednisolone and cimetidine. She experienced transient improvement, but soon cough, dyspnea and epigastralgia became worse. The specimens obtained by transbronchial alveolar lavage (BAL) and endoscopic gastric biopsy showed many giant cells containing inclusion bodies which were identified as cytomegalovirus (CMV). This time ganciclovir was started in addition to prednisolone. Then she gradually improved and after repeated BAL and the gastric biopsy after treatment showed no inclusion body in the specimen.
Although leukocytopenia was significant for this patient, ganciclovir is considered to be useful for controlling CMV infection in both the lungs and stomach.

View full abstract

A 5-year-old girl developed cutaneous aspergillosis due to Aspergillus flavus while undergoing remission induction therapy for actute lymphocytic leukemia. Of six serum samples obtained during the acute stage of Aspergillus infection, four showed antigenemia (6.5-22.9 ng/ml) determined by enzyme-linked immunosorbent assay (ELISA). However, five serum samples obtained after treatment with amphotericin B and granulocyte-colony stimulating factor showed negative results for antigens. Sera obtained on day 17 after the detection of skin lesions showed seroconversion in precipitin antibody determined by an immunodiffusion test and in immunoglobulin (Ig) A class antibody determined by ELISA, while sera obtained on day 24 showed seroconversion of IgG and IgM class antibodies.
The patient achieved complete remission of leukemia and was discharged on the 92nd day of hospitalization. No signs of disseminated or deep-seated fungal infections were present during the hospitalization.
Assays for serum antigens may be of value for the early diagnosis of invasive aspergillosis. Moreover, persistently negative results for antigens in accordance with antibody responses may correlate with recovery from the infection.

View full abstract