二尖瓣疾病左心室充盈压的多普勒评估

由于在瓣膜区域、左心室松弛性和僵直性等方面易于发生混淆．传统多普勒测量对二尖瓣疾病病人左心房压的预测上受到限制。然而，在犬和临床研究中，组织多普勒成像所测定的充盈早期二尖瓣血流速率起始段和房室环的充盈早期速率之间的时间窗（time interval between the onset of early diastolic mitral inflow velocity and annular early diastolic velocity，TE-Ea）与左心室舒张时间常数（time constant of left ventricular relaxation，t）良好相关，并且不受上述瓣膜区域、左心室舒张和僵直等变量的影响。因此在病人人群中开展这项研究，检验其用途。     

Identification of women with an increased risk of developing radiation-induced breast cancer: a case only study

Introduction

Medroxyprogesterone acetate (MPA) induces estrogen receptor (ER)-positive and progesterone receptor (PR)-positive ductal invasive mammary carcinomas in BALB/c mice. We sought to reproduce this MPA cancer model in C57BL/6 mice because of their widespread use in genetic engineering. Within this experimental setting, we studied the carcinogenic effects of MPA, the morphologic changes in mammary glands that are induced by MPA and progesterone, and the levels of ER and PR expression in MPA-treated and progesterone-treated mammary glands. Finally, we evaluated whether the differences found between BALB/c and C57BL/6 mouse strains were due to intrinsic differences in epithelial cells.

Methods

The carcinogenic effect of MPA was evaluated in C57BL/6 mice using protocols proven to be carcinogenic in BALB/c mice. In addition, BALB/c and C57BL/6 females were treated with progesterone or MPA for 1 or 2 months, and mammary glands were excised for histologic studies and for immunohistochemical and Western blot evaluation of ER and PR. Hormone levels were determined by radioimmunoassay. Isolated mammary epithelial cells were transplanted into cleared fat pads of 21-day-old female Swiss nu/nu mice or control congenic animals.

Results

MPA failed to induce mammary carcinomas or significant morphologic changes in the mammary glands of C57BL/6 mice. The expression of ER-α and PR isoform A in virgin mice was surprisingly much higher in BALB/c than in C57BL/6 mammary glands, and both receptors were downregulated in progestin-treated BALB/c mice (P < 0.05). PR isoform B levels were low in virgin control mice and increased after progestin treatment in both strains. ER-β expression followed a similar trend. No differences in hormone levels were found between strains. Surprisingly, the transplantation of the epithelial mammary gland cells of both strains into the cleared fat pads of Swiss (nu/nu) mice abolished the mammary gland morphologic differences and the ER and PR differences between strains.

Conclusion

C57BL/6 mammary glands are resistant to MPA-induced carcinogenesis and to hormone action. MPA and progesterone have different effects on mammary glands. Low ER-α and PR-A levels in untreated mammary glands may be associated with a low-risk breast cancer profile. Although we cannot at this time rule out the participation of other, untested factors, our findings implicate the stroma as playing a crucial role in the strain-specific differential hormone receptor expression and hormone responsiveness.     

Follow-up of breast carcinoma

The rationalization of the follow-up schedule for patients treated for breast cancer appears essential due to the high incidence of this disease. The authors retrospectively analyze their series (3,596 patients, from 1971 to 1990) to assess the patterns of both early loco-regional recurrences and distant metastases. Patterns and outcome of local and regional recurrences are reported according to site. The international literature on the subject is reviewed, and the schedule currently employed in the follow-up of breast cancer patients at the Radiotherapy Unit of Florence is reported. Due to the patterns of relapse a more intensive clinical follow-up schedule is suggested during the first 5 years. Less intensive follow-up continues over the whole patients' life span, since failures can occur even after 5 years. Mammography should be repeated every year in the same period to detect eventual homolateral and/or contralateral relapses. Other diagnostic tools should be employed only when symptoms set in. On the ground of the current literature on the subject, no negative impact on survival should be expected from this follow-up schedule.