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T Fukada

Publications and source records attributed to T Fukada.

66 records · Page 4Linked to original sources
PubMed1974

Genetic basis of nutritional requirements in Lactobacillus casei.

In a study of the genetic basis of multiple nutritional requirements in Lactobacillus casei, systematic attempts were made to isolate mutants that can grow in the absence of a specific nutrient required by the parental organism. Such mutants have successfully been isolated with respect to seven of twelve amino acids (aspartic acid, leucine, isoleucine, lysine, methionine, serine, and threonine) and three of four vitamins (pantothenic acid, nicotinic acid, and pyridoxal) tested, after extensive screenings employing various mutagens. Mutants that can grow without tryptophan were not isolated, but those that can grow on anthranilate or indole as well as on tryptophan were obtained at a frequency expected for single-step mutations. Activity of tryptophan synthetase was demonstrated in extracts of these anthranilate-utilizing mutants, but not in the parental strain. These results suggest that the multiple nutritional requirements of L. casei are often, if not always, due to one or a few small lesions such as base substitution mutations rather than large deletions affecting the genes involved in each biosynthetic pathway. The data would also imply that many of the biosynthetic pathways that are not fully functional in L. casei were active at one time and became nonfunctional during evolution of the present species.

Adenine↗
PubMedDate not supplied

Adult-onset subacute sclerosing panencephalitis: immunocytochemical and electron microscopic demonstration of the viral antigen.

We report a case of subacute sclerosing panencephalitis (SSPE) in a 52 year-old man, who developed rapidly progressive mental deterioration, myoclonic seizures, quadriplegia, and remained incapacitated until his death 4 years after the onset of symptoms. Immunocytochemical and electron microscopic studies are reported. Titers of measles virus antibodies were consistently high in both serum and cerebrospinal fluid, and periodic synchronous discharges were recorded on EEG. Suppressed cellular immunity was noted in skin test with phytohemagglutinin. The brain was extensively destroyed by inflammatory processes. There were either laminar or widespread areas of cortical necrosis associated with neuronophagia, neuronal loss, glial proliferation, and perivascular lymphocytic cuffing. Numerous intranuclear inclusions, in the neurons and glial cells, stained with immunoperoxidase using antiserum to SSPE virus; ultrastructurally, these inclusions were made of tubular nucleocapsids of paramyxovirus. Neurofibrillary changes were occasionally encountered in the pigmented neurons. The white matter showed extensive loss of myelinated fibers and increased numbers of astrocytes with bizarre nuclei. This well-documented case of SSPE in an adult might be related to a condition of impaired cellular immunity.

Antigens, Viral↗