Malignant melanoma: analysis of dose fractionation in radiation therapy

Thirty-five patients with 67 measureable cutaneous or lymph node metastases from malignant melanoma were treated with radiation therapy in a variety of total doses and dose fractions. There was no correlation between total dose and response rate. However, there was a strong correlation between fraction size and response rate. There were four (9%) complete responses in 43 lesions treated with fractions less than or equal to 500 rad (5 Gy) compared with 12 (50%) complete responses in 24 lesions treated with fractions greater than 500 rad (5 Gy) (P = .0006). Initial response rate was found to correlate strongly with local control at 1 year. The results were then analyzed with respect to lesion size, cutaneous versus nodal lesions, and site of cutaneous lesion (trunk, head and neck, or extremity). Correlation between fraction size and response rate was independent of lesion size, although there were fewer complete responses with increasing lesion size. Correlation was not seen in nodal lesions but was particularly striking in cutaneous lesions. This correlation was statistically significant only for cutaneous lesions of the extremities.     

The effect of cataract extraction with implant in glaucomatous eyes

The effect of cataract surgery in patients with glaucoma controlled by either topical medication or surgery was assessed in 64 patients. At one year there was a small significant fall in intraocular pressure (IOP) for eyes without previous surgery (preoperative IOP 18.9 ±4.7, range 12 to 35 mmHg; postoperative IOP 16.3 ±3.4, range 10 to 26 mmHg; P<0.01) and also for those with previous surgery (preoperative IOP 15.0 ±4.3, range 3 to 22 mmHg; postoperative IOP 14.2 ±3.7, range 6 to 22 mmHg, P<0.05). There was a significantly greater incidence of high rise in IOP to 30 mmHg or more immediately after operation in patients without (32%) than those with previous surgery (13%) ( x 2 = 3.9; P<0.05). Complications were minimal in each group. lridotomy to deliver the nucleus was necessary in nine eyes without and 21 with previous surgery. Cataract extraction usually causes only a small fall in IOP in glaucomatous patients. If a separate corneal section is used there is no loss of function of the filtering bleb in patients with previous glaucoma surgery.     

经腹腔镜开窗减压术治疗巨大非寄生虫性脾囊肿是有效的保脾术式

原发性脾囊肿是一种罕见的疾病,目前尚缺乏对该疾病的理想治疗方法的相关研究.大多数原发性脾囊肿是上皮性囊肿.近几年,腹腔镜脾脏外科手术普及率不断提高.该研究报告了关于经腹腔镜保脾手术治疗脾囊肿的相关经验.1996年至2006年间,作者治疗了11例有症状的非寄生虫性脾脏巨大囊肿病人.病人均诉左上腹涨满症状,触诊可扪及腹部包块.术前腹部超声及CT均已明确诊断.病人接受经腹腔镜脾脏囊肿部分切除术或脾脏囊肿开窗减压术.结果发现,7例病人为脾脏间皮囊肿,2例为脾脏表皮样囊肿,2例为脾脏假性囊肿,没有发现囊肿癌变.手术操作时间为62～85 min,无中转开腹.     

T-cell tolerance and autoimmunity to systemic and tissue-restricted self-antigens

Summary: We have used transgenic mouse models to examine the mechanisms of tolerance in CD4⁺ T lymphocytes to soluble, systemic and cell‐associated, tissue‐restricted self‐antigens. Anergy to an islet antigen, as a model of a tissue antigen, is dependent on the inhibitory receptor cytotoxic T‐lymphocyte antigen‐4 (CTLA‐4), and tissue‐restricted autoimmunity is inhibited by regulatory T lymphocytes. Anergy to a circulating systemic antigen can occur independently of CTLA‐4 signals, and it is induced primarily by a block in proximal receptor‐initiated signals. CD4⁺CD25⁺ regulatory T cells are generated in response to both forms of self‐antigens, but the induction is much more efficient with the tissue antigen. Receptor desensitization can be induced by the systemic antigen even in the absence of regulatory T cells, but tolerance can be broken by immunization much more easily if these cells are absent. Deletion of mature T cells is striking with the systemic antigen; there is little evidence to support peripheral deletion as a mechanism of tolerance to the tissue antigen. Thus, both distinct and overlapping mechanisms account for unresponsiveness to different forms of self‐antigens. These results establish a foundation for searching for genetic influences and pathogenic mechanisms in organ‐specific and systemic autoimmune diseases.