Biomedical subjects

C C Chung

Publications and source records attributed to C C Chung.

42 records · Page 3Linked to original sources

PubMed1990

Recombinant human prorenin from CHO cells: expression and purification.

The gene for human preprorenin was obtained from total RNA prepared from primary human chorion cells. An expression vector was constructed containing an SV40 early promoter, a human preprorenin cDNA, bovine growth hormone poly-A addition signal, and a dihydrofolate reductase (dhfr) expression cassette. This vector was inserted into the DXB-11 Chinese hamster ovary (CHO) cell line. The recombinant protein was exported by CHO cells into the tissue culture media. At harvest the prorenin levels ranged from approximately 1-5 mg/L. For prorenin isolation the cell culture supernatants were processed by filtration, concentration, dialysis, and batch extraction. Preparative-scale isolation of prorenin was accomplished using blue-dye chromatography and size-exclusion chromatography. The isolated prorenin yielded a single SDS-gel band with Mr approximately 40,000. The proprotein was characterized with respect to N-terminal sequence and N-linked sugar composition. Trypsin-activated renin prepared from the proprotein was characterized with respect to N-terminal sequence and pH-activity profile. Enzyme activity was measured with a newly developed fluorogenic peptide substrate containing the P6-P'3 sequence of human angiotensinogen.

Amino Acid Sequence↗

PubMed1985

Vertical abdominal fasciocutaneous flaps in the reconstruction of chest wall defects.

The use of a vertical abdominal fasciocutaneous flap in the reconstruction of chest wall defects is described. The technique has been successfully used in 8 patients and the advantages of such a fasciocutaneous flap in chest wall reconstructions are emphasised.

Abdominal Muscles↗

PubMed1985

Neuropsychological deficit and regional cerebral blood flow in schizophrenic patients.

The paper examined the relationship between the scales of the Luria Nebraska Neuropsychological Battery and measures of cerebral blood flow in a sample of 51 chronic schizophrenic patients without a history of brain damage. Of 88 correlations between the two sets of data, 22 were significant at the .05 level. The measurement of left anterior gray flow were particularly predictive of LNNB scores, although all correlations were at a moderate level, ranging from -.24 to -.38. The data are consistent with the hypothesis that neuropsychological testing performance in schizophrenics is related to brain function rather than merely reflecting deficits due to anxiety or other psychiatric features which have been hypothesized to invalidate neuropsychological assessment in this population. The data are also consistent with the notion that schizophrenia is more likely associated with left-anterior functioning, and that gray-matter measures in rCBF are effective predictors of neuropsychological performance.

Adult↗

PubMedDate not supplied

Interchangeability of a semiadjustable articulator.

PURPOSE: The purpose of this study was to investigate whether the interchangeability of new Hanau semiadjustable articulators fulfills the manufacturer's criterion (102 microns) in the mediolateral direction and the defined 166-micron criterion three dimensionally and whether the articulators maintain the same interchangeability as new articulators after a period of function. MATERIALS AND METHODS: The spatial deviations in three dimensions of ten new, ten 18-month-old, and ten 30-month-old Hanau articulators were measured with a field-inspection gauge and compared to those of a master articulator. RESULTS: Compared to the master articulator, nine of 10 new articulators met the manufacturer's criterion of articulator interchangeability in the mediolateral direction. However, only four of the 10 articulators fulfilled the criterion for three-dimensional interchangeability. The articulators were found to be interchangeable among the groups when the spatial deviations of test articulators from the master articulator at the position of the lingual cusp of the right maxillary first premolar were compared. However, using the geometric mean deviations of test articulators, the 30-month group was not interchangeable with the new and the 18-month articulator groups. CONCLUSION: This limited study revealed that most of the articulators tested met the manufacturer's criterion of articulator interchangeability, but most did not pass the three-dimensional interchangeability test. Clinicians should be aware of the amount of occlusal error in the range of 0.2 mm that may result from interchanging dental casts on the articulator system. The articulator system might be able to maintain the same level of interchangeability for up to 18 months of routine use.

Analysis of Variance↗

PubMedDate not supplied

A case of schistosomal appendicitis.

Acute appendicitis is a great masquerader in surgical practice; its diverse clinical presentation can sometimes lead to delay in diagnosis. Nonetheless, the underlying aetiology of acute appendicitis may not be apparent if the appendix is not sent for histological examination.

Aged↗

PubMedDate not supplied

Gastrointestinal autonomic nerve tumour presenting as small bowel volvulus: a rare disease with a rare presentation.

A 78-year-old Chinese woman presented with recurrent postprandial abdominal pain. Computerised tomography revealed a small bowel tumour causing volvulus of a segment of the small bowel. Laparotomy confirmed an extraluminal ileal tumour with partial volvulus of the involved small bowel segment. Small bowel resection was done. Histological and ultrastructural studies confirmed a gastrointestinal autonomic nerve tumour. We review the medical literature on this rare tumour.

Aged↗