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H C Tang

Publications and source records attributed to H C Tang.

6 recordsLinked to original sources

Organization of human cardiovascular-expressed genes on chromosomes 21 and 22.

The recent availability of the sequenced and annotated DNA sequences of chromosomes 21 and 22 has initiated the next phase in the human genome project: the application of this resource. One facet of these data is that they provide a list of ordered genes along the chromosome that can be capitalized upon to determine gene position effects. Specifically, the physical position and distribution of genes along the chromosomes may be related to gene expression in specific organs or organ systems. In this report we index the subset of genes constituting the human "cardiovascular genome" on chromosomes 21q and 22q as well as report the identification of several "cardiovascular gene" clusters. These gene clusters are suggestive of a higher order of tissue-specific gene regulation at the chromosomal level.

Cardiovascular System↗

Identification, characterization, and mapping of expressed sequence tags from an embryonic zebrafish heart cDNA library.

The generation of expressed sequence tags (ESTs) has proven to be a rapid and economical approach by which to identify and characterize expressed genes. We generated 5102 ESTs from a 3-d-old embryonic zebrafish heart cDNA library. Of these, 57.6% matched to known genes, 14.2% matched only to other ESTs, and 27.8% showed no match to any ESTs or known genes. Clustering of all ESTs identified 359 unique clusters comprising 1771 ESTs, whereas the remaining 3331 ESTs did not cluster. This estimates the number of unique genes identified in the data set to be approximately 3690. A total of 1242 unique known genes were used to analyze the gene expression patterns in the zebrafish embryonic heart. These were categorized into seven categories on the basis of gene function. The largest class of genes represented those involved in gene/protein expression (25.9% of known transcripts). This class was followed by genes involved in metabolism (18.7%), cell structure/motility (16.4%), cell signaling and communication (9.6%), cell/organism defense (7.1%), and cell division (4.4%). Unclassified genes constituted the remaining 17.91%. Radiation hybrid mapping was performed for 102 ESTs and comparison of map positions between zebrafish and human identified new synteny groups. Continued comparative analysis will be useful in defining the boundaries of conserved chromosome segments between zebrafish and humans, which will facilitate the transfer of genetic information between the two organisms and improve our understanding of vertebrate evolution.

Animals↗

[Analysis of 59 cases of non-traumatic sudden death in various neurological diseases].

Sudden death is a common complication of myocardial infarction, necrotic pancreatitis and other diseases. Physicians usually neglect the possibility of neurological disorders. 59 cases of sudden death among 314 autopsied cases with neurological diseases were analyzed. The most frequent cause of neurological sudden death was cerebrovascular disease (CVD). It was present in 53 (89.9%) cases. 48 of them had hemorrhagic CVD. 37 of these 48 cases were due to hypothalamic lesions. In 37 cases general autopsy was performed; pathological abnormalities of heart, lungs, stomach etc, were found in 28 of them. In conclusion, the size and location of the lesion correlated with the prognosis of the disease. Concomitant multiple organ damage may deteriorate the lesion. Awareness of sudden death resulting from CVD may elevate the rate of correct diagnosis.

Cerebral Hemorrhage↗

Optimal low dosage of acetylsalicylic acid (ASA) for the prevention and treatment of ischemic cerebrovascular disease in geriatric patients.

A series of 108 geriatric patients with ischemic cerebrovascular disease were treated with low dose aspirin (acetylsalicylic acid, ASA). Daily doses of 100 mg, 50 mg and 25 mg were administered to three groups of 36 patients. Changes in platelet aggregation responses were dynamically observed in 64 (22 normal subjects, 42 patients). Monitoring of 22 normal subjects revealed inhibition of platelet aggregation at a dose of 300 mg or 100 mg which could last as long as 7 days. This suggests that 100 mg or less could be clinically effective. Satisfactory inhibitory effects on platelet aggregation were observed in all three groups, with 14 patients in each group given daily doses of 100 mg, 50 mg and 25 mg during four weeks' observation. The most effective inhibition was obtained in the 50 mg group. Therefore, the authors recommend 50 mg/d as the optimal dosage for low dose aspirin therapy in geriatric patients.

Aged↗