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The chromosome fragile sites of cultured peripheral lymphocytes from 40 members of 4 high risk cancer families and 10 members of 4 low risk cancer families in Linxian County were analysed. The results showed that 46 fragile sites in 7045 lymphocytes expression at 502 times (7.13%) were found in high risk cancer families and 8 fragile sites in 1053 lymphocytes expression at 26 times (2.47%) were found in low risk cancer families. There was a significant difference between the two groups (P less than 0.01). In 46 fragile sites carried by 40 members of high risk cancer families, 27 were common, 5 rare, 12 provisional and 2 new fragile sites. Among them, the fragile sites at 1p22-p36 and 4q21-q31 were detected in members of high risk cancer families and in patients with esophageal cancer, meanwhile, uniform breakpoint in chromosome deletion and rearrangement was also found in 4 esophageal cancer cell lines. Therefore, the author conjectures that these fragile sites at 1p13-p36 and 4q21-q31 may be fragile site-specific for high risk cancer families and patients with esophageal cancer, and they may be breakpoint-specific for esophageal cancer cells. These fragile sites may play an important role in esophageal carcinogenesis in high risk cancer families.

Two step processes were taken in computer diagnosis of gastric dysplasia. 1. 5 measurement values of dysplastic glandular tube obtained by using image analysis system were taken as the basis for judging the degree of dysplasia. Three glandular tubes of dysplasia were measured in each case. 2. Computer pathology diagnostic program using BASIC language ran in IBM computer. 5 parameters were input into computer for three stage-diagnosis. The first stage: 5 parameters were counted basing on three models to obtain three values which reflected the objective feature of the same glandular tube from different aspects. The second stage: diagnosis of a dysplastic glandular tube was obtained depending on the three values judged synthetically. Variate 'N' was introduced for controlling the first and second stage diagnosis of the three glandular tubes. The third stage diagnosis started as soon as N = 3. The third stage: diagnostic values of three glandular tubes were balanced and analysed depending on diagnostic criteria to reach the final diagnosis.

Using the technique of AG-NORs, the number of silver-stained NORs on chromosomes of the peripheral lymphocytes from 10 cancer patients, 10 high risk cancer family members and 10 normal individuals was compared. It was found that the total mean value of AG-NORs was 5.46 +/- 0.00/per cell in cancer patients, 5.62 +/- 0.01/per cell in high risk cancer family members and 7.03 +/- 0.07/per cell in normal subjects. The total mean value of AG-NORs was markedly lower in the first two groups than in the third group (P less than 0.001). It seems to be due to the decrease of the transcribed activity of rRNA gene on chromosomes of the cultured lymphocytes in the first two groups. A probable relation between the carcinogenesis and decrease of NORs is shown. The transcribed activity of rRNA gene gives the expression to AG-NORs numbers with which the relation to carcinogenesis is briefly discussed with a review of the literature.

Recent studies from our laboratory indicate that high density lipoproteins (HDL) and apolipoproteins-AI, -AII, and -CI stimulate the release of human placental lactogen (hPL) from human placental explants and trophoblast cells. However, the intracellular mechanisms by which HDL stimulate hPL release are unknown. Since earlier investigations from our laboratory indicated that pharmacological agents that increase intracellular cAMP levels [such as (Bu)2cAMP, isobutylmethylxanthine, and cholera toxin] also stimulate hPL release, we have performed studies to determine whether the stimulation of hPL release by HDL may be mediated by cAMP. Exposure of an enriched fraction of enzymatically dispersed hPL-producing cells to HDL (10-1500 micrograms/ml) for 0.5 h resulted in a significant dose-dependent stimulation of both cAMP production and hPL release. The half-maximal effective HDL dose for cAMP production and hPL release was 60-100 micrograms/ml. When perifused trophoblast cells were exposed to HDL (150 micrograms/ml) for 25 min, the increase in cAMP production preceded the increase in hPL release. The increase in cAMP production occurred during the first 5 min of exposure to HDL and reached a maximum (12.1 +/- 1.6-fold greater than base-line levels) 10 min after exposure. The increase in hPL release occurred about 10 min after the initial increase in cAMP production, reaching a maximum (9.7 +/- 1.4-fold greater than base-line levels) 15 min after exposure to HDL. HDL (300 micrograms/ml) also stimulated a 2.7-fold (P less than 0.001) increase in adenylate cyclase activity in placental plasma membranes, a magnitude of stimulation comparable to that caused by epinephrine (1 mM). Apolipoprotein-AII stimulated cAMP formation and hPL release in trophoblast cells with a pattern identical to that of HDL. These results, the first to demonstrate an effect of HDL on adenylate cyclase activity and cAMP production, strongly suggest a role for cAMP as a second messenger in HDL-stimulated hPL release.

While heavy exposure to inorganic lead is capable of inducing symptomatic neuropathy in man, the subclinical neuropathy due to low levels of occupational lead exposure remains to be proved. The reported results of electroneurographic studies on lead workers, however, have been controversial. In this study, 40 lead smeltery workers and 50 non-exposed referents were investigated. The air concentrations of lead at worksites were 0.25 to 42.5 mg/m3. The geometric means of PbB, PbU and delta-ALAU in lead exposed group were 40.03 micrograms/dl, 71 micrograms/l and 4.68 mg/l respectively, which were significantly higher (P less than 0.001) than those (7.01 micrograms/dl, 6.0 micrograms/l and 1.81 mg/l respectively) in the reference group. There were no clinical symptoms or signs of nerve damage in either group. Alcoholism and diabetes were excluded in both groups. Nerve conduction velocity was measured by a DISA 1500 electromyograph in both groups. Eleven electroneurographic parameters, including motor nerve conduction velocity (MCV) and distal latency (DML) of median, ulnar and peroneal nerves as well as sensory nerve conduction velocity (SCV) and distal latency (DSL) of median, ulnar and sural nerves, showed statistically significant differences between the two groups. However, the results of electroneurographic measurements of each individual in the lead-exposed group were all within the normal range. There was no correlation between the blood-lead levels and the neurophysiological measurements except for the median MCV. No correlation was seen between the median MCV and the exposure duration.(ABSTRACT TRUNCATED AT 250 WORDS)

The spontaneous and mitomycin-c (MMC) induced sister chromatid exchanges (SCE) and chromosome aberrations in cultured lymphocytes from members of "high risk" and "low risk" esophageal cancer families in Linxian County were studied. The results showed that the frequencies of the spontaneous SCE of "high risk" and "low risk" esophageal cancer groups were 7.8 +/- 0.25 and 8.3 +/- 0.25/per cell. There were no difference between these two groups (P greater than 0.5). The frequencies of the SCE induced by MMC in "high risk" and "low risk" esophageal cancer groups were 43.8 +/- 2.4 and 21.6 +/- 1.1/per cell. There were noteworthy difference (P less than 0.001). However, the frequencies of the spontaneous and MMC induced chromosome aberrations in "high risk" cancer families were higher than those of the "low risk" ones.

An epithelial cell line was established from the leg skin of a patient with palatine carcinoma. On the basis of the studies of biological characteristics, such as rapid cell growth, neoplastic morphology, a large group B marker chromosome, the ability of the transplanted cells to produce tumor nodes in Wistar newborn rat, the cell possessing the structure of low differentiated squamous carcinoma and skin-like tissue, etc., we conclude that the PcaSE-1 cell line is an abnormal epithelium cell line.

The authors continuously observed the effect of Chuanxiongqin on the microcirculation of hamster cheek pouch by use of the Dual-Window Television Automatic Estimating System. It was seen that the caliber of arterioles, the microcirculatory velocity, and blood flow all decreased after local application of noradrenaline and all increased and returned to normal 1 to 30 min after local administration of Chuanxiongqin. Microcirculatory perfusion, however, could not be improved by normal saline or Iluangqi. The effect of Chuanxiongqin on the pulmonary capillary permeability was also investigated in rats. Pulmonary edema was induced in rats by adrenaline administration. Evans blue was injected intravenously and the amount of Evans blue in broncho-alveolar lavage fluid was estimated. It was found that Evans blue was increased in broncho-alveolar fluid of rats with pulmonary edema, and this increase could be lessened by Chuanxiongqin.

Gastric dysplasia is a very important precancerous change recognized only by histological examination. The objective indexes of diagnosing the dysplastic change are hardly established. It is desirable to translate enumeration data of histopathology into measurement data in order to obtain objective measurement criteria for the diagnosis of gastric dysplasia. In this paper, three measurement indexes N/C, P1/D1 and P2/D2 are proposed. N/C represents the ratio of nucleus and cytoplasm, showing the cellular atypia. P1/D1 represents the ratio of outer perimeter of the measured glandular tube and diameter of an equivalent circle, showing the structural atypia. P2/D2 is the ratio of perimeter of the irregular shape by tracing the end of the nuclei near the lumen of the tube and diameter of an equivalent circle, showing both cellular and structural atypia. The results indicate that these three measurement criteria can be taken as the objective indexes for diagnosing gastric dysplasia and predicting its potential malignancy.

To determine the influence of ventilation control and work practices on the health of workers potentially exposed to organophosphate and carbamate compounds, we examined a total of 989 employees from pesticide factories in Taiwan during 1986-1987. Each employee was examined by a physician, and a blood sample was drawn for plasma cholinesterase, complete blood count, and liver and renal function tests. Forty-one employees with medical conditions that might alter the plasma cholinesterase were excluded. Results showed that 43 of 515 production employees had decreased plasma cholinesterase as compared with four of 340 non-production employees. Production employees working under adequate ventilation control seemed to have a lower prevalence of decreased plasma cholinesterase than those under inadequate ventilation control, although the difference was not statistically significant (p = 0.242). There was a significant association between the level of housekeeping and work practices and the prevalence of decreased plasma cholinesterase (p = 0.022). We conclude that inadequate ventilation control and poor work practices may create a potential danger of pesticide poisoning among production employees in Taiwan and should be corrected immediately.

In general, the diagnosis and grading of dysplasia of the gastric mucosa depends upon the pathologist's experience. The authors suggest N/C, P1/D1, P2/D2, R/R and NCI as 5 morphometric indexes and objective criteria in diagnosis and grading of this lesion. N/C involves the ratio of nuclei to cytoplasm; P1/D1 is the ratio of the dysplastic tubule perimeter to the diameter of its equivalent circle (obtained by transformation of the irregular perimeter); P2/D2 is the ratio of perimeter obtained by tracing the edges of nuclei bordering the lumen of the dysplastic tube to the diameter of the equivalent circle; R/R is the ratio of P1/D1 to P2/D2, which remains almost constant in spite of the fact that P values of tubules cutting through normal branches may increase in cases without atypia. For this reason, R/R may be regarded as an index for estimating the reasonability of the sampling. NCI is the ratio of nuclear perimeter to the diameter of its equivalent circle. In accordance with the above indexes, the diagnosis and grading of dysplasia can be assigned by computer analysis.