An experimental model was designed for direct, quantitative studies of hemodynamic and morphologic parameters in the microcirculation. It consists of implanting a modified Algire chamber in the dorsal skin flap of hamsters and the implementation of two permanent catheters in jugular vein and carotid artery. The microcirculation was studied using intravital microscopy and television techniques for in situ measurements of blood cell velocity and vascular diameters. Due to the poor contrast between blood cells, blood capillaries and surrounding s.c. tissue, microvascular beds were visualized using fluorescent microscopy after i.v. injection of 0.2 ml of 5% FITC-Dextran 150. The combination of optical elements and low amounts of FITC-Dextran improved the contrast of the televised image without changing macro- and micro-hemodynamic parameters, and blood plasma was delineated as bright structure against the substantially darker background of red blood cells and surrounding tissue. This permitted the quantitative study of practically all blood vessels within a given field of s.c. tissue in unanesthetized animals. Blood cell velocity in arterioles was 0.7-1.1 mm/s, 0.2-0.7 mm/s in midcapillaries and reached 0.6 mm/s in collecting venules. Since i.v. injection of drugs and systemic pressure measurements are possible in this model, it provides a unique means for studying the reactivity of the microcirculation over a prolonged period.

We have analysed products of lipid peroxidation reactions and activities of antioxidant enzymes in cancerous breast tissue and in corresponding reference tissue. In addition, the serum lipid peroxidation and peroxyl-radical-trapping capacity of breast cancer patients were compared to those of healthy subjects. A total of 23 patients with breast cancer participated in this study. In the cancerous tissue, catalase activity was lower than in the reference tissue, while the activities of superoxide dismutase, glutathione peroxidase and the hexose monophosphate shunt were elevated. The content of thiobarbituric-acid-reactive material was slightly lower in the cancerous tissues, but the levels in serum were found to be elevated in patients with breast cancer. The amounts of conjugated diene double bonds were essentially equal both in the cancerous and in the reference tissue. Moreover, in breast cancer patients the serum levels of diene conjugation and the peroxyl-radical-scavenging capacity did not differ from those measured in healthy subjects. This study indicates that the antioxidant defence system is altered in cancerous breast tissues, but does not support the hypothesis suggesting that formation of lipid peroxides in the tumour tissue itself is of primary importance in the carcinogenesis.

To study the effects of family history and reproductive, anthropometric, and dietary factors on the risk of breast cancer among low risk populations, we conducted a hospital-based case-control study involving 908 patients with breast cancer and their matched controls, in Japan. A positive family history of breast cancer significantly increased the risk of breast cancer (odds ratio = 1.52, 95% confidence interval: 1.14-2.03). The risk further increased with increasing number of family members affected. Obesity, single marital status, fewer births, a late childbirth, and less consumption of green-yellow vegetables and dairy products were also associated with an increased risk of breast cancer. These associations were independent in multivariate analyses. There was no increase in risk associated with consumption of high fat foods. When analyzed by menopausal status, the association with family history of breast cancer, especially in the first degree of relatives, was more evident for premenopausal breast cancer. The associations with obesity and lower consumption of dairy products were more pronounced for postmenopausal breast cancer, while those with lower parity and single marital status were stronger for premenopausal breast cancer.

The authors studied the role of 70-Kd heat shock protein (HSP70) in the progression of breast cancer by examining the correlation between the expression of HSP70 and epidermal growth factor receptor, c-erbB-2, p53, and estrogen receptor in 124 cases of invasive primary human breast cancers. Positivity of an anti-HSP70 monoclonal antibody, C92, was closely associated with the elevation of estrogen receptor (P < .008), whereas it inversely correlated with the expression of p53 (P < .01). In addition, the expression of HSP70 correlated inversely with the expression of epidermal growth factor receptor, although the correlation was not statistically significant (P = .06). These results suggest that the expression of HSP70 plays a role in the progression of human breast cancer.

Mutations in either of two recently identified genes, BRCA1 and BRCA2, are thought to be responsible for approximately two-thirds of all cases of autosomaldominantly inherited breast cancer. To examine the nature and frequency of BRCA1 and BRCA2 mutations in Japanese families exhibiting a high incidence of breast cancer, we screened 78 unrelated families in this category for mutations of these two genes. Examining the entire coding sequences as well as exon-intron boundaries of both genes by polymerase chain reaction (PCR) single-strand conformation polymorphism (SSCP) and multiplex-SSCP analysis, we identified possible disease-causing alterations in BRCA1 among affected members of 15 families and in BRCA2 in another 14 families. In 15 of those 29 families, the affected individuals carried missense mutations, although most germline mutations reported worldwide have been deletions or nonsense mutations. Our results, indicating that missense mutations of BRCA1 and BRCA2 tend to predominate over frameshifts or nonsense mutations in Japanese breast cancer families, will contribute significantly to an understanding of mammary tumorigenesis in Japan, and will be of vital importance for future genetic testing. pattern of inheritance of breast cancer were evaluated. For each family, a pedigree was prepared on the basis of a family member known to be affected. Key wordsOccurrence of cancer within each pedigree was confirmed by obtaining medical records and pathology reports for all available family members whether living or deceased. The criteria for selecting "breast cancer families" for this study were as follows: (a) at least three first-degree family members with breast cancer or (b) two or more first-degree family members with breast cancer, either early-onset, bilateral, or accompanied by a history of primary cancer(s) of other organs. Blood samples were obtained from affected family members through the aforementioned Societies. Genomic DNAs were extracted from fresh blood under standard protocols (Kunkel et al. 1977). Mutation screening SSCP-analysis.The entire coding sequences of BRCA1 and BRCA2, and associated exon-intron boundary sequences, were examined by PCR-SSCP analysis. The PCR primers used for PCR-SSCP analysis have been described elsewhere (Katagiri et al. 1996b, Miki et al. 1996.Each genomic DNA (50␣ ng) was amplified in a reaction mixture containing 10 ml of 1 ϫ PCR buffer (25␣ mM TAPS, 50␣ mM KCl, 2␣ mM MgCl 2 , and 1␣ mM β-mercaptoethanol), 20␣ mM dNTPs, 5␣ pmol primers, 2␣ mCi of α[ 32 P]dCTP (3000␣ Ci/mmol, 10␣ mCi/ml), and 0.5 units of Taq polymerase (Boehringer Mannheim, Mannheim, Germany). PCR conditions were 1 cycle at 94°C for 2␣ min, then 30 cycles at 94°C for 30␣ s, 60°C for 30␣ s, and 72°C for 30␣ s with final elongation at 72°C for 5␣ min. Each reaction mixture was diluted with 50␣ ml of 95% formamide dye and 20␣ mM ethylenediaminetetraacetic acid (EDTA), incubated at 85°C for 5␣ min, and electrophoresed in a 6% polyacrylamide gel containing 5% glycerol and 0.5 ϫ 90␣ mM Trisborat...