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Biomedical subjects

H R Chen

Publications and source records attributed to H R Chen.

At least 55 records · Page 3Linked to original sources
PubMed1989

A newly developed method for treatment of oral lichen planus with ultraviolet irradiation.

In the past, treatment of oral lichen planus (OLP) was usually discontinued by patients due to the many adverse effects such as drug-induced side effects, scarring, etc. In this study, 35 patients with severe OLP which was verified histologically were subjected to irradiation. The lesions were irradiated with ultraviolet (UV) light at wave lengths of 320-400 nm for 5-10 minutes per single exposure once a week. During each irradiation, the patients were protected with eye goggles and no photosensitizer was added. Soreness and discomfort of the oral lesions were markedly relieved after irradiation for 4 treatments. By comparing the pre- and post-treatment findings from clinical, histological and immunohistochemical examinations, 30(85.7%) out of the 35 patients were either cured or improved after 8 treatments of UV-A irradiation. The advantages of UV-A irradiation therapy are as follows: (1) fewer erythemic-induced side effects: (2) marked improvement of lesions within a short period; and (3) no malignant transformation during a period of 5 years following the irradiation.

Female↗
PubMed1987

A domain structure common to hemopexin, vitronectin, interstitial collagenase, and a collagenase homolog.

The sequence of hemopexin consists almost entirely of two homologous domains joined by a short hinge region; the domain structure, with its own characteristic features, is derived from four short tandem repeats. Each repeat contains several alternating clusters of hydrophobic and hydrophilic residues but also has some individual features as a consequence of its position in the domain. Here we present evidence for the presence of a single hemopexin domain in an interstitial collagenase and in a collagenase homolog, as well as of two copies of the domain in vitronectin. The functions of all of these proteins involve binding to various proteins and smaller molecules. We suggest that the presence of this domain may facilitate these binding activities. Our analysis also suggests a tentative identification of substrate-binding and catalytic domains in the collagenase and its homolog.

Amino Acid Sequence↗
PubMed1985

Surgical treatment of spontaneous cerebellar hemorrhage.

UNLABELLED: Spontaneous cerebellar hemorrhage accounts for 5%-10% of intracerebral hemorrhage in most series. From June 1979 to June 1983 we had 26 surgical cases of spontaneous cerebellar hemorrhage. There were 15 men and 11 women. The typical history was sudden onset of severe headache, vomiting, dizziness, and inability to walk. Disturbance of consciousness was usually a late feature. Common signs were truncal ataxia, nystagmus, conjugate eyeball deviation, small miotic pupils with or without light reflex and abducens palsy. Surgical indications are (a) disturbance of consciousness, (b) signs of brainstem compression and (c) hematoma with transverse diameter greater than 3 cm. The overall surgical mortality was 34.6%. Twenty-two patients underwent suboccipital craniectomy to evacuate hematomas with or without ventriculostomy; mortality rate was 27%. Four patients underwent ventriculostomy only; mortality was 75%. Causes of death were (a) brainstem failure, six patients; (b) airway obstruction, one patient; (c) chest infection, one patient; (d) chronic renal failure, one patient. CONCLUSION: (a) suboccipital craniectomy to evacuate the hematoma is the most effective procedure where treatment is indicated; (b) the clinical recovery of the survivors show that 31% return to work, 38% are moderately disabled but take care of themselves, and 31% remain dependent on others; (c) deeply comatose patients may still benefit from early operation.

Adult↗
PubMed1985

Nucleic acid sequence database VI: Retroviral oncogenes and cellular proto-oncogenes.

The databases of the Protein Identification Resource at the National Biomedical Research Foundation (NBRF) contain nucleic acid and protein sequences from 18 retroviral oncogenes (v-onc) and 8 cellular proto-oncogenes (c-onc). Comparison of the sequences between the v-onc and c-onc genes reveals: (i) The c-src, c-abl, c-mos, c-fos, c-ras, c-myb, c-myc, and c-sis genes contain coding regions that are highly conserved in the respective v-onc genes with a small number of base changes. (ii) There are more transitions than transversions. (iii) Some of these base changes are silent mutations and others generate amino acid substitutions in the viral proteins. The causes of these base changes in the coding sequences and the significance to oncogenic transformation of the amino acid substitutions in the viral proteins remain to be determined.

Animals↗