Search

Filterable forms of Nocardia (i.e., filterable nocardiae) are characterized as spherical structures containing many granules. They fluoresce brilliantly under ultraviolet light when stained with acridine orange and are acid-fast in paraffin-containing broth cultures. An accumulation of acid-fast lipochrome bodies, similar to filterable nocardiae, is observed in glial cells of the midbrain nigral lesions found in Parkinson's disease (PD). Preliminary results from experimental infection with filterable nocardiae revealed a possible site of infection in a region of the nervous system associated with movement disorders. Here we examined the preferential site of filterable nocardiae infection in the brain and investigated the effects of various chemicals and biological substances in relation to this preferential site on nocardiae growth in vitro. Examination of tissue samples immunostained for filterable nocardiae revealed that neurons in the olfactory bulbus and the midbrain periaqueductal gray area were immunopositive for filterable nocardiae. Several erythrocytes within blood vessels of the brain were also immunopositive. In addition, a dose-dependent relationship was observed between the growth of filterable nocardiae and erythrocyte lysates. These results suggest first that the preferential site of infection for filterable nocardiae might be erythrocytes, but could also be neurons in the bulbus olfactorius as well as in the midbrain periaqueductal gray area. Second, filterable nocardiae might grow to be branching cylindrical tubules such as that of mycelial bacteria in the presence of erythrocyte lysates.

To confirm or refute the proposed link between nocardiae and Parkinson's disease (PD), we investigated the presence of acid-fast spherical structures similar to filterable nocardiae at the midbrain nigral lesions of three patients with PD. Many clusters of acid-fast lipochrome bodies were dense around blood vessels in the two patients with Hoehn and Yahr stage II and III PD. These clusters were present in the vicinity of melanin-pigmented neurons in the three PD patients studied. Examination of adjacent hematoxylin-and-eosin-stained sections indicated that they consisted of yellow-green granules, bodies, and aggregates in ballooned glial cells. On the other hand, no clusters of acid-fast lipochrome bodies were observed at the compacta region of three control patients. Our results suggest that the immunological and genetic relationship between the acid-fast lipochrome bodies and filterable nocardiae should be investigated.

In yeast extract-supplemented brain heart infusion (BHI) broth cultures of Nocardia asteroides GUH-2, many spherical bodies (SBs) were frequently seen nearby filamentous cells. They showed no gram-positivity when Gram stain was applied. When acridine orange stain was applied, many of them showed different green fluorescence from bright orange fluorescence of the filamentous nocardiae under ultraviolet light. Their acid-fastness appeared to depend on the presence of paraffin. Using the polymerase chain reaction (PCR) method, 16S rRNA genes were detected in SB-containing broth cultures inoculated with culture filtrates from broth cultures of the strain and identical to that of N. asteroides. These results suggest that SBs are cell wall-defective (CWD) forms which result from the spontaneous mutation of N. asteroides GUH-2.

Nocardia asteroides GUH-2 was not acid-fast when grown in brain heart infusion (BHI) broth. When grown in BHI broth supplemented with paraffin, many filamentous cells showed acid-fastness after treatment with 1% acid-alcohol as the decolorizing agent. When treated with 3% acid-alcohol, filamentous cells were not acid-fast. In addition to the acid-fast filamentous cells of nocardiae, unknown acid-fast spherical bodies were observed in the paraffin-supplemented BHI broth cultures.

Nocardia is a genus of aerobic Gram-positive bacteria which forms filamentous cells that fragmented into rod-shaped or coccoid elements or L-forms. According to the literature N. asteroides causes encephalitis with parkinsonian features, and it may be an unknown etiologic agent causing encephalitis with a parkinsonian syndrome. Because there are no reliable immunologic tests routinely used for diagnosing nocardial infection, less severe CNS infections with nocardiae may not be recognized or may be attributed to unknown or incorrect etiologic agents. Recently, it was shown that sublethal doses of N. asteroides causes an L-DOPA-responsive movement disorder with Lewy-like bodies in mice. In this study, we detected antibodies to nocardia in the serum of patients with Parkinson's disease (PD). Sera was diluted in PBS and added in two-fold dilutions to coccoid and rod-shaped cells of nocardia attached to nonfluorescence slides. IF test demonstrated antibodies to coccoid and rod-shaped cells of nocardia in the serum from 20/20 patients with PD at a titer greater than 1:10, and 14 controls showed 10 positively. The results suggested that not only PD patients but also age-matched healthy volunteers are routinely exposed to and naturally infected with nocardia-related microorganisms. A further reliable immunologic test will be required.

The following results were obtained from the comparison of cefoperazone (CPZ) with cefazolin (CEZ), cephalothin (CET) and cefoxitin (CFX) in respect to their antibacterial action against anaerobic bacteria: 1) CPZ showed an antibacterial spectrum which was comparable to those of the known antibiotics, CEZ, CET and CFX. CPZ was particularly effective against anaerobic Gram-positive bacteria. 2) CPZ showed a distribution of susceptibility against clinically isolated strains which was comparable to those of CEZ, CET and CFX, CPZ was slightly inferior to CFX against B. fragilis and B. thetaiotaomicron, but was somewhat superior to any of CEZ, CET and CFX against anaerobic Gram-positive rods and B. distasonis. 3) The susceptibility of B. fragilis and F. necrophorum to CPZ decreased with an increase in the amount of inoculation, while C. perfringens and P. asaccharolyticus did not show any difference in susceptibility with the amount of inoculation. 4) The values of MIC and MBC of CPZ showed good coincidence with each other, thereby testifying its superior bactericidal action. 5) Natural resistant mutants were not obtained. 6) According to the examination of resistance in a test tube, P. variabilis did not show any appreciable increase in resistance, but F. varium increased its resistance rapidly. 7) CPZ was inferior only to CFX in stability against the beta-lactamase of B. fragilis. All of CEZ, CET and CMD lacked stability against the beta-lactamase of B. fragilis. 8) CPZ was found effective for the treatment of experimental subcutaneous abscess in mice caused by F. necrophorum.

An electron microscopic study revealed that, within 30 min after inoculation into the ligated ileal loop of anesthetized mice, cells of Salmonella typhi GIFU 10007 adhered to the M cell surface of Peyer's patch lymphoid follicle epithelium, and induced almost complete destruction of M cells. The M cell cytoplasms were pinched off and extruded from the epithelial lining into the luminal space together with the lymphoid cells primarily enfolded into the corresponding M cells. When two or more M cells were destroyed, a large defect in the epithelial lining was apparent, and a number of bacteria appeared near the basal lamina of the epithelial lining. These findings suggest, as far as anesthetized murine ileal loops and strain 10007 are concerned, that ileal M cells are the target cell at an early stage of S. typhi infection and the infection may further progress to deeper tissues and to the general circulation.

Scanning electron micrograph of HeLa S3 monolayered cells, inoculated with viable bacteria of a Salmonella typhi strain GIFU 10007, revealed that the extended microvilli tangled the bacteria within 10 min after inoculation. The micrographs of HeLa cells, at 1 hr after inoculation, indicate the following: shortening of bacterium-attached microvilli, subsiding of tangled bacteria into microvilli bush, and then attachment of bacterial soma to cell surface making the cell membrane depressed. The transmission electron micrographs, at 1 hr after inoculation, demonstrated the findings of interaction between HeLa cell and S. typhi 10007, similar to those observed on scanning electron micrographs. Hair-like fine structures from the soma of challenge organisms were also observed. They were in contact with HeLa cell microvilli and cell membrane. The bacteria were first partially and then totally surrounded by the HeLa cell plasma membrane. One, two, or several bacteria with intact outer membrane were enclosed in intracytoplasmic membrane-bound vacuoles. Fragmented vacuolar membrane was still visible around the intracellularly accumulated bacteria at 24 hr after inoculation. The viable cells of S. typhi 10007 are regarded as internalizing into HeLa cells by a process of endocytosis and to multiply within the membrane-bound vacuoles.