Alloy electrodes with high hydrogen overvoltage for analytical use in voltammetry. Some preliminary results.

Liquid mercury and liquid diluted mercury amalgams have been the major electrode systems employed in voltammetry and related methods. This is mainly due to their high overvoltage to hydrogen, which enables the determination of heavy metals (zinc, nickel, cobalt, etc.) and other species with high negative half-wave potentials; the toxicity of mercury and liquid diluted mercury leads to ever increasing restrictions in their use. The use of such systems may even be forbidden in the future, at least in online systems for work in the field. Recent work, carried out in our laboratory, has demonstrated that a non-toxic solid dental amalgam may be used as the electrode material, conveniently replacing mercury. An extension of this work has shown that electrode materials comprising a metal or a compound with low hydrogen overvoltage change their hydrogen overvoltage properties substantially when contaminated with even small amounts of metals or compounds which show high hydrogen overvoltage. This extends greatly the range of potentially available electrode systems and thereby analytical possibilities of voltammetry. This new discovery also makes it possible to produce solid electrodes that have high overvoltage to hydrogen without any use of mercury.

Mycobacterium hassiacum sp. nov., a new rapidly growing thermophilic mycobacterium.

A new rapidly growing, scotochromogenic mycobacterium was isolated from urine. This strain is thermophilic (it grows at 65 degrees C), tolerates 5% NaCl, and was unable to utilize any of the sugars tested or citrate or to take up iron. The isolate splits benzamide, urea, nicotinamide, and pyrazinamide and is sensitive to streptomycin, ethambutol, cycloserine, ciprofloxacin, and chlarithromycin but resistant to isoniazid, rifampin, and prothionamide. These characteristics clearly place this organism in a new mycobacterial species, which was confirmed by the unique 16S rRNA nucleotide sequence. The high level of similarity between this rapid grower and Mycobacterium xenopi is surprising. For this new rapidly growing scotochromogenic and thermophilic mycobacterium we propose the name Mycobacterium hassiacum sp. nov.

Isolation and characterization of a unique group of slowly growing mycobacteria: description of Mycobacterium lentiflavum sp. nov.

A distinct group of slowly growing mycobacteria was identified on the basis of growth characteristics, biochemical and lipid profiles, and nucleic acid analyses. The isolates showed growth at 22 to 37 degrees C, yellow pigmentation, and negative tests for Tween 80 hydrolysis, nicotinic acid, nitrate reductase, and urease; tests for arylsulfatase, pyrazinamidase, and heat-stable catalase were variable. Analysis of cellular fatty acids by gas-liquid chromatography and mycolic acids by thin-layer chromatography and high-performance liquid chromatography indicated a distinctive pattern which was unlike those of other species. Determination of the 16S rRNA gene sequence showed a unique sequence closely related to Mycobacterium simiae and M. genavense. On the basis of DNA homology studies, we suggest that these organisms are representatives of a novel species, for which the name M. lentiflavum sp. nov. is proposed.

[Avian mycobacteria]. / Aviäre Mykobakterien.

The avian mycobacteria have been identified first in relation to their virulence for hens. But this property was not definitely to correlate with serovars. Furthermore, this heterogenicity was to confirm on molecular level. Therefore it was necessary to introduce a M.avium complex beside true M.avium. M.avium has special relevance to AIDS patients. This fact shows that the reasons for infections by these facultatively pathogenic mycobacteria are more complicated as accepted.

Mycobacterium interjectum, a new species isolated from a patient with chronic lymphadenitis.

Mycobacterium-like organisms, isolates 2081/92 and 4185/92, were recovered from a lymph node of a child with chronic lymphadenitis. The growth characteristics, acid-fastness, and mycolic acids of the isolate were consistent with those for Mycobacterium species. The isolates were biochemically distinct from described Mycobacterium species, although they most closely resembled M. scrofulaceum. Comparative 16S rDNA sequencing showed that these isolates represent a new slow-growing Mycobacterium species which is named M. interjectum. Our results demonstrate the importance of 16S rDNA sequencing for recognizing the diversity of species within the genus Mycobacterium.

Pulmonary tuberculosis due to bacille Calmette-Guérin.

Immunotherapy using bacille Calmette-Guérin (BCG) has gained increasing acceptance in the management of superficial bladder cancer. Systemic reactions after intravesical instillation of BCG are rare. However, when the therapy is complicated, the lung often becomes involved. Since the pathogenesis of lung infiltrates after immunotherapy is unknown, we report on a patient who developed a lung infiltrate after receiving BCG immunotherapy for bladder cancer. The infectious etiology was established by culture confirmation of a BCG strain in the bronchoalveolar lavage fluid.

Mycobacterium intermedium sp. nov.

Strains of a new type of slowly growing mycobacterium were repeatedly isolated from sputum from a patient with pulmonary disease. This photochromogenic organism grew at 22, 31, 37, and 41 degrees C, possessed catalase, acid phosphatase, esterase, beta-galactosidase, and arylsulfatase activities, and hydrolyzed Tween. It did not produce nicotinic acid or have nitrate reductase, acetamidase, benzamidase, isonicotinamidase, nicotinamidase, pyrazinamidase, succinidamidase, and acid phosphatase activities. Urease activity was variable. The organism is susceptible to ethambutol and resistant to isoniazid and streptomycin. A mycolic acid analysis revealed the presence of alpha-mycolates, alpha'-mycolates, and keto-mycolates. The results of comparative 16S rRNA sequencing placed this organism at an intermediate position between the rapidly and slowly growing mycobacteria. On the basis of the pattern of enzymatic activities and metabolic properties, the results of fatty acid analyses, and the unique 16S rRNA sequence, we propose that this organism represents a new species, for which we propose the name Mycobacterium intermedium. The type strain is strain 1669/91; a culture of this strain has been deposited in the Deutsche Sammlung von Mikroorganismen und Zellkulturen as strain DSM 44049.

Isolation of Mycobacterium simiae from the environment.

An examination of 18 sphagnum samples collected in two different biotopes of the coastal region of southeastern Madagascar revealed an unexpectedly high positivity for mycobacteria (83.3%). The concentration of alcohol acid-fast bacilli reached a high level of 10(5) and 10(6)/g, respectively, compared with the sphagnum biotopes in moderate climates. Besides the habitat-specific mycobacterial species in sphagnum vegetation, like M. sphagni, M. gordonae and M. madagascariense, potentially pathogenic species, like M. avium, M. scrofulaceum and M. xenopi and M. marinum, were found. Furthermore, pathogenic M. simiae was found in sphagnum vegetation of Madagascar, first time isolated in the environment until now. It should be considered as a potential source of infection for human and animals.

Clinical evidence of systemic persistence of bacillus Calmette-Guerin: long-term pulmonary bacillus Calmette-Guerin infection after intravesical therapy for bladder cancer and subsequent cystectomy.

A patient with urothelial bladder carcinoma is reported who suffered from culture proved pulmonary bacillus Calmette-Guerin (BCG) infection 14 months after a single course of intravesical BCG and 11 months after subsequent radical cystectomy for progressive cancer. This unusual case raises the question of the ultimate fate of intravesically instilled BCG and the possible persistence of these mycobacteria in remote organs. Systemic spread and dormant survival at least in some cases are suggested, and therapeutic and diagnostic consequences are discussed.

Mycobacterium confluentis sp. nov.

A new rapidly growing mycobacterium was isolated from human sputum. This organism grew at 22, 31, 37, and 41 degrees C and possessed catalase, acid phosphatase, acetamidase, urease, nicotinamidase, pyrazinamidase, and nitrate reductase activities. It did not produce nicotinic acid, hydrolyze Tween, or have benzamidase, isonicotinamidase, succinidamidase, and arylsulfatase activities. A mycolic acid analysis revealed a simple, unique pattern. The organism is susceptible to antituberculotic drugs. A comparative 16S rRNA sequence analysis placed this organism within the confines of the genus Mycobacterium, most closely related to the thermotolerant rapidly growing species. On the basis of the pattern of enzymatic activities and metabolic properties, as well as the unique 16S rRNA sequence, we propose that our single strain represents a new species, for which we propose the name Mycobacterium confluentis. The type strain is strain 1389/90; a culture of this strain has been deposited in the German Collection of Microorganisms and Cell Cultures as strain DSM 44017.

[Microbial diagnosis of atypical mycobacteria]. / Mikrobiologische Diagnostik der atypischen Mykobakterien.

The introduction of the radiometric system in the diagnostic of tuberculosis caused an increase of positive specimens and shortened the time of detection markedly. This is true for strains of tuberculosis complex and especially atypical mycobacteria. The majority of these is highly resistant to drugs. Therefore, the conventional method of susceptibility tests gives no relevant results for therapy. These are obtained when combinations of drugs are tested. The most important character of atypical mycobacteria is optional pathogenicity. This is why one has to decide for each isolation whether an infection has to be assumed or a colonization only. Atypical mycobacteria are present in the environment of men and are able to multiply under unfavourable conditions. Therefore, they are a potential hazard for men.

[Avian mycobacteriosis caused by strains not yet identifiable]. / Aviäre Mykobakteriose durch bisher nicht identifizierbare Stämme.

This paper reports on a group of strains of Mycobacterium avium-intracellulare recently isolated from various bird species. The strains in question could not be integrated into the known 28 serovars. The host spectrum includes birds of several avian orders. Clinical, serological, pathoanatomical, and histopathological results are being discussed. During observations of the clinical course in some infected birds, it could be shown that the excretion of the agent could cease for several months. The diagnosis of the new group of serovars was possible only by culture. Antibodies of several serovars demonstrated in life birds did not correspond with the isolates. Therefore, these antibodies were interpreted as serological crossreactions.

[Indirect sensitivity testing of pyrazinamide]. / Indirekte Empfindlichkeitsprüfung von Pyrazinamid.

Susceptibility tests of M. tuberculosis for pyrazinamide are to perform by indirect methods only. Differences in susceptibility of different methods are only low. We prefer the NSA-method, because it is to use like other drugs. Only M. tuberculosis is susceptible for PZA, not M. bovis, BCG and also not atypical mycobacteria.

[Atypical mycobacterioses: diseases caused by Mycobacterium malmoense]. / Atypische Mykobakteriosen: Erkrankungen mit Mycobacterium malmoense.

M. malmoense, once a rarity among the atypical mycobacterial infections, is presently being detected with ever greater frequency in human examination material. Strains of this organism apparently belong to the facultative pathogenic mycobacteria, as the cases described in this article show. Apart from other patients with mycobacterial infections of the lungs, the first case of infection of the lymph nodes in the neck is described.

[Incidence of infections with mycobacteria in HIV infected patients]. / Hüfigkeit von Infektionen mit Mykobakterien bei HIV-Infizierten.

In subjects with HIV infection, mycobacteria are frequently identified. The most commonly seen species are M. avium-M. intracellulare. On the other hand, there is considerable variation in the data regarding the incidence of infections with M. tuberculosis; in fact, these data correspond with the differences in prevalence of tuberculosis in the respective general population.

[Mycobacterium simiae in Germany]. / Mycobacterium simiae in Deutschland.

Mycobacterium simiae has been isolated from a patient with a pulmonary infection. During 1 1/2 years 10 different isolates of this strain could be cultivated. In this case it has not been proved that Mycobacterium simiae was the etiological agent, although the probability is very high.

[15th anniversary of the Mycobacteria Study Group]. / 15 Jahre Arbeitskreis Mykobakterien.

In Germany the Working Group Mycobacteria was founded 15 years ago. During this period new methods have been introduced or improved. Today all new techniques are examined by quality control and the results are published in international journals or are reported at special meetings. That is why in Germany the diagnostic of mycobacteria has reached a very high level.

Mycobacterium scrofulaceum, serovar Cole.

Cole strains of Mycobacterium, originally introduced as M. scrofulaceum serovar No. 44 and later rejected as belonging to M. avium were re-investigated and compared with well-documented strains of M. scrofulaceum. Our data show that the Cole serovar belongs to M. scrofulaceum and should be re-introduced as serovar No. 44 of M. scrofulaceum.

Granulomatous pulmonary reactions after instillation of Mycobacterium gordonae. Light and electron microscopic investigations on the rat model.

Pathogenicity of Mycobacterium gordonae in humans has so far been reported in the literature in the form of case reports only. Systematic experimental investigations have not been published. For this reason, the pathogenicity of two Mycobacterium gordonae strains isolated from human ivestigation material were tested in animal experiments. Measured amounts of in some cases live and in some cases heat-killed M. gordonae were instilled into the right lower lobe of the lung of anesthetized Wistar rats by means of a polyvinyl catheter. The tissue changes were investigated at graduated time intervals between 1 h and 24 weeks by light and electron microscopy. Small granulomas consisting of leukocytes and macrophages develop in the lung tissue 3 days after the instillation. Under the electron microscope, intracellular mycobacteria can be demonstrated. These do not proliferate. After 2 weeks, sarcoid granulomas have formed from epitheloid and giant cells. Casefying necroses are absent. Electron microscopically, it can be shown that the mycobacteria are broken down intracellularly in phagolysosomes, so that sarcoid granulomas free of bacteria are left behind.