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H R Huang

Publications and source records attributed to H R Huang.

3 recordsLinked to original sources

Purification and cloning of carp nephrosin, a secreted zinc endopeptidase of the astacin family.

We have purified a secreted proteinase of 23 kDa from carp head kidney by sequential column chromatography on a Reactive Blue 72-agarose dye affinity column and an FPLC Mono-P column. The secretion of this proteinase from carp head kidney can be stimulated by high concentrations of potassium. Since the carp proteinase is present mainly in the head kidney, kidney, and spleen (all of which are lymphohematopoietic organs), it is named nephrosin. The carp nephrosin is most sensitive to metal chelators, but not to inhibitors specific for other classes of proteinases. A cDNA clone has been isolated from a carp head kidney cDNA library by immunoscreening with a polyclonal antiserum raised against purified nephrosin. The cloned cDNA is 1086 base pairs in length and has an open reading frame encoding a protein of 273 amino acids, including a 19-amino acid signal peptide and 56-amino acid propeptide. The deduced amino acid sequence shows moderate levels of identity to medaka HCE1 (52.5%), medaka LCE (50.7%), crayfish astacin (33.2%), murine meprin-alpha (34%), and murine meprin-beta (33.5%), all members of the astacin family of zinc endopeptidases. Nephrosin is the first member of the astacin family found in lymphohematopoietic tissues.

Adrenal Cortex

Internal jugular phlebectasia.

Phlebectasia, defined as abnormal venous dilation, may occur in a number of different sites. Two cases with definite diagnosis of internal jugular phlebectasia were reported. The first case was a 6-year-old girl with a bulging mass on right neck for 3 years. Angiography and CT scan showed definite diagnosis, and the bulging mass was resected from the internal jugular vein (IJV). The second case was a 66-year-old female patient, also complained of a bulging mass on her right neck. Sonogram and CT scan also showed the same diagnosis. Because it did not bother the patient, she was just under close observation. From the three kinds of diagnostic modalities, we found sonography is an effective technique because of its clarity, safety and low cost.

Aged

In vivo cloning of proline genes and its expression in Escherichia coli.

The wild type proA+, B+ genes of E. coli were cloned in vivo using a plasmid containing a mini-Mu replicon, pEG5005. The cloning frequency was about 1.46 x 10(-3)/Kanr transductant. Genetic and biochemical analysis of these clones indicated that the proA+, B+ genes are on the plasmid pEG5005. The secretion of proline were assayed for 500 Pro+ clones. However, no proline accumulation was detected. A Pro+ clone pPR3 was mutagenized in vivo by NTG and the mutants resistant to D-proline were obtained. One of the Dpr mutants pPR7 was found to produce 0.35 mg/ml proline in a proA B deletion strain. When pPR7 was transferred into a proline producing strain, the yield of proline increased up to 2.5 mg/ml, which is 7 and 2.5 times higher than that of the donor and recipient respectively. The physical maps of pEG5005 and pPR3 were roughly established.

Chromosome Mapping