Gossypol (GP), a male antifertility agent, and Gossypolone (GN), a major metabolite of GP, have been shown to have a suppressive effect on steroidogenesis in bovine luteal cells. We examined the effect of GP, GN and serum obtained from rats given GP (GP-serum) on steroidogenesis in porcine granulosa cells (PGC). To obtain GP-serum, 50-60 day old Copenhagen rats received GP (12.5 mg/kg B.W. /day, sc) for 14 days. PGC were incubated with GP, GN and GP-serum at different doses for 24 hours. GP and GN significantly suppressed Progesterone (P₄) and Estradiol (E₂) release in a dose-dependent manner, respectively. GP-serum also significantly suppressed P₄ release in a dose-dependent manner. The magnitude of suppression of P₄ obtained by GP-serum could not be explained by the amount of GP remaining in the serum. Therefore, the inhibition of P₄ release by GP-serum could not be solely attributed to GP.

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Using 2′, 7′-dichlorofluorescein diacetate (DCFH-DA) as an indicator for the intracellular formation of H₂O₂ and free radicals, we measured DCFH-oxidation (DCF fluorescence) of neutrophils by flow cytometry.
The DCF fluorescence intensity of unstimulated neutrophils in whole blood was the same as the autofluorescence of neutrophils. However, that of unstimulated isolated neutrophils was higher than autofluorescence. The DCF fluorescence of isolated neutrophils was higher than that of neutrophils in whole blood with or without stimuli, and was decreased to the intensity of neutrophils in whole blood by the addition of plasma or erythrocytes. The DCF fluorescence of neutrophils in whole blood indicates the oxidative state of neutrophils in vivo. The determination of DCFH-oxidation of neutrophils in isolated leukocytes is also necessary to evaluate precisely the oxidative state of neutrophils.
In cerebrospinal fluid (CSF) cells from patients with menigitis, the DCF fluorescence intensity of unstimulated neutrophils was higher than the autofluorescence of CSF neutro-phils. The DCF fluorescence of CSF neutrophils stimulated with PMA showed increased. intensity over that of unstimulated CSF neutrophils. The DCF fluorescence of CSF neutro-phils, both unstimulated and stimulated with PMA, were decreased with the addition of plasma but not with the addition of CSF.
The present study suggests that flow cytometric assay of DCFH-oxidation in neutrophils shows an overall balance between the antioxidant activity and redox state of the cells.

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Most of the gastric cancers investigated in this study were detected during mass screening at a Medical Check-up Center. The research period was 5 years, from 1990 to 1994. The total number of patients undergoing initial gastric examinations was 300, 658. Four point eight percent of these needed detailed examinations, and 77.2% actually underwent detailed examinations. Over the 5 years, the number of gastric cancers detected was 253. The rate of detection of these cancers was almost unchanged every year, with the average rate of change being 0.11%. The rate of detected gastric cancers was investigated according to age and sex. No cancers were found below age 29, and the rate gradually rose over age 30. Over age 50, the rate in males was twice that in females. The rate of early gastric cancers was 66.4% of all reported cancers. As regards location of 253 cases, 16.5% were in the C-area, 45.8% in the M-area, 36.2% in the A-area; 19.2% were in the greater curvature, 33.9% were in the lesser curvature, 17.3% in the anterior wall, and 26.1% in the posterior wall. The sizes of the lesions were as follows: 11.5% were below 1.0 cm, 29.6% were from 1.1 cm to 2.0 cm, 46.6% were from 2.1 cm to 5.0 cm, and 12.3% were over 5.1 cm. It was considered that indirect X-rays were slightly inferior to direct X-rays in detecting early gastric cancer. The X-ray positionings in which cancers were detected were: 75.7% by supine double contrast and 48.6% by compression in 144 cases of early cancer. On the other hand, the rate were 75.6% by supine double contrast, and 51.2% by compression in 82 cases of advanced cancer. A similar tendency was found in one-shot X-ray positioning which revealed cancers. The rate of gastric cancer notdetected by X-ray pictures was 5.9% of the 253 cases. The size of the cancers notdetected by X-ray was within 2.0 cm in all cases. 58.7% of the 155 early cancer patients and 48.2% of the 83 advanced cancer patients had examinations the previous year. Therefore, it is clear that some cases of advanced cancer were not detected in the mass gastric screenings. Endoscopically, 7 cases of gastric cancer were diagnosed correctly by means of repeated biopsies which were needed 3 or 4 times over 3 to 18 months owing to pseudonegative findings on the first bioptic examination. Consequently, it is necessary to make naked eye diagnosis by endoscopic examination. Six cases of death from gastric cancer were certified within one year after normal diagnosis during the mass screening. Three cases were Borr. 4, 2 cases Borr. 3, and 1 case was Borr 2. A retrospective investigation of X-ray pictures showed that it would have been difficult to identify the lesions in these cases.
The above results show that the accuracy of examinations and diganosis must be raised in mass gastric screenings, but it is doubtful whether relying on the present methods of screening will lead to a marked improvement. For the purpose of increasing the effectiveness of mass gastric screening, we would emphasize the necessity of the following new tests; serum pepsinogen measurement, reinvestigation of patient's ages, shortening the intervals between examinations in high risk groups, using direct X-rays rather than indirect X-rays, and intermitted endoscopic examinations.

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In order to elucidate the molecular mechanism of the tissue-and stage-specific expression of globin genes, the possible regulatory role of the 5′-flanking region of the rat β-globin genes was investigated by determining the nucleotide sequence and measuring the CAT transfection activity of a series of deletion mutants. Results obtained in the present study are summarized as follows:
1. Transcription initiation sites of the rat IIβ-, IIIβ-, and 0 β-globin genes were determined to be 52 base pairs (bp) 5′-upstream of the translation initiation codon (ATG), in each gene by primer extension analysis.
2. The nucleotide sequences of 5′-flanking regions of each gene (IIβ: -3819/+51, IIIβ: -716/+51, 0β: -727/+51) were determined. Dot matrix search of the individual sequences revealed the occurrence of about 300 bp of alternating purine and pyrimidine repeats at a region extending from the nucleotide positions -757 to -1049 5′ to the transcription initiation site of the IIβ-globin gene.
3. CAT transfection assay using constructs with deletions in 5′-flanking regions indicated that a negative regulatory effect occurs in the region between -757 and -1049 of the IIβ-globin gene, corresponding to that containing the purine/pyrimidine repeats mentioned above. These results strongly suggest that the presently identified purine/pyrimidine stretch may act as a repressor.
4. Dot matrix analysis between the 5′-flanking nucleotide sequence of the rat II/β-globin gene and those of adult type β-globin genes of other species showed that the repeat sequence existing in the 5′-flanking region of the rat gene is very homologous to that found in a similar region of the mouse β-major globin gene, which has been reported to contain a possible repressor element.

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