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L Kato

Publications and source records attributed to L Kato.

At least 19 recordsLinked to original sources
PubMed1994

Water soluble complexes of C14 and C16 fatty acids and alcohols in media for cultivation of leprosy-derived psychrophilic mycobacteria.

Host-grown Mycobacterium leprae cell suspensions oxidized water-soluble complexes of palmitic acid, myristic acid, cetyl alcohol, and myristyl alcohol prepared with randomly methylated-beta-cyclodextrin as host molecules. Gas chromatography analysis showed that the water-soluble complexes retained their chemical structure following sterilization in the autoclave. Bioavailability of the two long-chain fatty acids and the corresponding long-chain alcohols was confirmed by Warburg manometric techniques with host-grown M. leprae cell suspensions. Inoculated with host-grown M. leprae cells in chemically well-defined, simple liquid and agar media, acid-fast bacilli were cultivable in primary cultures and subcultures at 10 degrees C with (NH4)2SO4 as the N source and water-soluble palmitic acid, myristic acid, cetyl alcohol or myristyl alcohol as the C and potent energy sources. M. phlei oxidized the complexed palmitic acid and myristic acid but not cetyl alcohol or myristyl alcohol. On agar media with any of these four carbon sources and (NH4)2SO4 but not ammonium thioglycolate as the N source, M. phlei grew abundantly at 36 degrees C. In liquid media only myristyl alcohol supported growth of M. phlei without any growth with palmitic acid, cetyl alcohol or myristic acid. The leprosy-derived, cold-loving cultures ("M. psychrophilum") were not fully tested for classification and identification. The cells are strongly acid-fast facultative psychrophiles, adapted in subcultures to mesophilic growth. They grow in chemically well-defined media with 14 and 16 C long-chain fatty acids or alcohols as the C and energy sources. None of the cultures grow on Low-enstein or 7H9 media. Heat-killed suspensions of the 4th and 6th subcultures provoke Mitsuda-type late skin reactions in tuberculoid, borderline and borderline-tuberculoid but not in lepromatous leprosy volunteers. When grown with (NH4)2SO4 as the N source (but not with the reducing agent ammonium thioglycolate) the subcultures multiplied abundantly in the foot pads of mice. It became evident that leprosy-derived, facultative psychrophilic mycobacteria really exist. Mycobacteria of this cluster do not distinguish between 14 or 16 C long chains with COOH or CH2OH as terminal bindings. Cells are quite aerophilic and grow preferentially on agar slant surfaces.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1990

The demystification of leprosy: a multifactorial problem.

Abolishment of misbeliefs and misconceptions, unfounded fear and prejudice are factors as important in leprosy control as prevention, early detection and therapy. Concrete measures of demystification are proposed. Identify and divulge the absolute truth about leprosy. Calling leprosy "Hansen's disease" did not result in demystification. Patients know that the two terms are identical. Treating them as human beings attracts more patients to the healers than the Hansenologian ritual. Contrary to statements, no major advances are being made in the field of bacteriology, immunology, molecular biology, mode of transmission and epidemiology of leprosy. Not a single new drug has been discovered in 26 years. Vaccination is a dubious venture. The question arises as to whether the right priorities are promoted in leprosy research. Cultivation of the leprosy bacillus is the sine qua non of any further progress. This field of research is a lost and totally neglected priority. Consequently we have no pharmacological model for badly needed of ultrapotent antileprosy drugs. Syphilis is now cured with a single dose of penicillin. A drug as potent against leprosy should not be a mission impossible if an appropriate pharmacological model--the in vitro culture--is available. The multifactorial problem of demystification is a difficult but not an impossible task. Less sensationalism, more real progress in research, selecting the right priorities, achieving the "ultimate drug", shelter, food, shoes, soap and broom for every human on this planet constitute the road to demystification.

Anti-Bacterial Agents↗
PubMed1984

In vitro cultivation of Mycobacterium X from Mycobacterium leprae infected tissues in propane-tetradecane medium (a preliminary communication).

Host grown Mycobacterium leprae and cultures of Mycobacterium X, cultivated from M. leprae infected armadillo and human specimens, were inoculated into propane and propane-tetradecane media. The media contained in one litre distilled water KH2PO4, 7 g; Na2HPO4, 0.5 g; (NH4)2SO4, 2 g; MgSO4, 0.1 g; ferric ammonium citrate, 20 mg and yeast extract (Difco), 0.1 g. Twenty ml media, distributed into each of 50 ml screw cap tubes, were inoculated with the bacilli and bubbled aseptically for 10 s with 99% purity propane gas. Tetradecane-propane media were prepared by adding 0.1 ml tetradecane to each of the tubes containing 20 ml propane medium. When incubated at 32 degrees C a logarithmic growth rate was counted in the propane-tetradecane media following a one to two week latency period. The time of division was estimated at seven days. In the propane-tetradecane medium, growth occurred at the interface of the tetradecane oil and water as a thin veil developing into a 1 to 3 mm thick emulsion in two to three months. No growth occurred in the propane medium and growth was extremely slow in the tetradecane medium. When added to the tetradecane medium, propane considerably shortened the latency period and the generation time, resulting in increased bacterial yield. Bacilli were strongly acid-fast; the culture did not grow on Löwenstein-Jensen or in Dubos media, but produced the localized disease typical of M. leprae in the foot pads of mice.

Alkanes↗
PubMed1984

Propane and tetradecane as carbon sources for in vitro cultivation of Mycobacterium lepraemurium in a liquid medium (a preliminary communication).

Three strains of host grown Mycobacterium lepraemurium and five strains of Mycobacterium lepraemurium, grown on egg yolk medium, were inoculated into propane-tetradecane media. The media contained in one litre distilled water: KH2PO4, 7 g, Na2HPO4, 0.5 g, (NH4)2SO4, 2 g, MgSO4, 0.1 g, ferric ammonium citrate, 20 mg, and yeast extract (Difco), 0.1 g. Tetradecane 0.1 ml was added to each tube containing 20 ml of the medium. Media were sterilized in the autoclave. Following inoculation with the bacilli, the cultures were bubbled aseptically with 99% purity propane gas for 10 s. When incubated at 32 degrees C, logarithmic growth rate was counted in the cultures. Bacilli were strongly acid-fast. Growth occurred at the interface of the tetradecane oil and water as a thin weil, developing into a one to three millimeter thick emulsion in two to three months. Cultures were transferred into fresh media at two to three month intervals. Growth pattern in the subcultures were indistinguishable from the growth in the primary cultures. The cultures did not grow on Löwenstein-Jensen or in Dubos media, but produced the characteristic disease of murine leprosy when injected subcutaneously into mice. Bacilli isolated from the subcutaneous lepromas of mice were again cultivable in the propane-tetradecane medium, but not on Löwenstein-Jensen or in Dubos.

Alkanes↗
PubMed1983

In vitro cultivation of Mycobacterium X from Mycobacterium leprae-infected tissues in acetone-dimethylsulfoxide-tetradecane medium.

Several strains of mycobacteria were cultivable from Mycobacterium leprae-infected human and armadillo tissues in a liquid medium containing three dimethyl analogs: dimethylketone, dimethylsulfoxide, and tetradecane [CH3 . (CH2)12 . CH3]. The medium contained KH2PO4, 7.0 g; Na2HPO4, 1.0 g; (NH4)2SO4, 2.0 g; MgSO4, 0.1 g; iron ammonium citrate, 0.1 g; DMSO, 10 ml; and acetone, 150 ml in distilled water ad one liter. Tetradecane 0.1 ml was added aseptically to each tube, containing 10 ml of the sterile medium. The media, inoculated with M. leprae were incubated at 38 degrees C and shaken vigorously twice weekly. Growth developed as a fine emulsion at the upper phase of the two-phase system. This was homogenized by mechanical shaking, permitting growth estimation by turbidity measurements. Microscopic examination showed unmistakably the slow but abundant multiplication of acid-fast rods. The logarithmic growth rate was measurable during two to three months, followed by a plateau. The strains are maintained in subcultures by regular transfer into the same medium at two- to three-month intervals. The cultures and subcultures do not grow on Löwenstein or in Dubos media, but in the foot pads of mice they produce a multiplication similar to that obtained following injection of host-grown M. leprae. The cultures are tentatively designated as Mycobacterium X. The relationship of Mycobacterium X to the pathology of leprosy is not clear.

Acetone↗