Search PubMed⌕ Search

Biomedical subjects

S H Chang

Publications and source records attributed to S H Chang.

At least 181 records · Page 10Linked to original sources

The first nucleotide sequence of an organelle transfer RNA: chloroplastic tRNAphe.

The primary sequence of phenylalanine tRNA (tRNAphe) from the chloroplasts of Euglena gracilis has been determined: pG-C-U-G-G-G-A-U-A-G-C-U-C-A-G-D-U-G-Gm-U(U)-A-G-A-G-C-G-G-A-G-G-A-C-U-G-A-A-A-A-PSI-C-C-U-U-G-U-m7G-Py-C-A-C-C-A-G-T-psi-C-A-A-A-U-C-U-G-G-U-U-C-C-U-A-G-C-A-C-C-A. This represents the first nucleotide sequence determined for an organelle tRNA. As do all other tRNAPhes thus far sequenced, chloroplastic tRNAPhe contains 76 nucleotides. Both in the nature of its modified nucleotides and in its sequence (although the sequence of all known tRNAPhes is quite similar), chloroplastic tRNAPhe more closely resembles procaryotic tRNAPhes than it resembles those from the cytoplasm of eucaryotes. There are eight positions in the tRNAPhe molecule where nucleotides are invariant in procaryotes but differ from invariant nucleotides in eucaryotes; at five of these positions, chloroplastic tRNAPhe is similar to procaryotes. The possible evolutionary significance of this intermediate type of structure is discussed.

Base Sequence↗

Wilms' tumor in a multilocular cyst of the kidney (cystic Wilms' tumor).

A 2-year-old boy had a Wilms' tumor of the left kidney that appeared during physical examination as an abdominal mass and on gross examination as a multilocular cyst. Multilocular cyst of the kidney is a rare but distinctive congenital lesion. Its true biologic behavior is unknown. Although simple nephrectomy is sufficient for most lesions, more aggressive procedures are recommended for those lesions that contain Wilms' tumor (cystic Wilms' tumor).

Child, Preschool↗

Escherichia coli isolation from raw milk in central and southern Taiwan and their susceptibility to drugs.

From September 1972 to May 1973, 285 raw milk samples and 25 samples of high temperature treated retail milk were examined for Escherichia coli. High temperature treated mild was negative but from raw milk samples 320 strains of E. coli were isolated, among which 25 were enteropathogenic. Using Poly A, Poly B and nonovalent antisera whose pathogenic strains were classified into 6 serotypes: 0-26, 0-55, 0-119,0-125, 0-126 ad 0-128. About half (12) of them belonged to 0-119. Three pathogenic E. coli were sensitive to all of the 8 antibiotics tested while others were resistant to 1-3 antibiotics. Among the 295 nonpathogenic strains, 115 were sensitive to all antibiotics whereas the rest were resistant to 1-5 kinds of antibiotics.

Animals↗

RNA transcription by the virion polymerases of five rhabdoviruses.

The presence of a virion-associated RNA-dependent RNA polymerase in five serologically distinct rhabdovirus isolates (vesicular stomatitis virus [VSV] Indiana, VSV New Jersey, Cocal, Chandipura, and Piry viruses) has been demonstrated. The enzyme for each virus has been shown to be a transcriptase capable of synthesizing in vitro RNA which is complementary to the viral genome. By sequence analyses it has been shown that, for each rhabdovirus, transcription is multiply initiated with specific 5' nucleotide sequences. The results indicate that, for all five viruses, the initiation of transcription involves similar sequences (e.g., pppApCpGp..., pppGpCp..., and possibly one or two other sequences), suggesting relatedness and some genome conservation among these viruses.

Arboviruses↗