Pain relief by xenograft of subarachnoid microencapsulated bovine chromaffin cells in cancer patients

The bovine chromaffin cells (BCC) implanted into the subarachnoid space can release analgesic substances such as opioid peptides and ealeeholamines. Clinical trials have provided the evidence that the implantation of polyvinylchloride ( PVC) hollow fiber encapsulated BCC by surgery can relief the pain in cancer patients. In the present study, BCC were encapsulated in alginate-polylysine-alginate (APA) mieroencapsules which protect the grafting of xenogeneic cells from host immune system anil allow BCC to function effectively without using immunosuppression agents. The microencapsulated BCCs (5 X 106~—8 X 106) were transplanted into the subarachnoid space I^._s of 17 patients who suffered from chronic cancer pain and had to have long-term administration of analgesics. The pain scores and morphine intake tesl showed that microencapsulated BCC graft totally stopped the chronic pain in three of the patients over a period of 200 days and in the other three over a period of 100 days. The resulls suggesl thai APA microencapsulated BCC xenotransplantation could be a novel alternative approach to managing pain of cancer patients.     

纳滤去除地表水中微污染物生产饮用水

为了研究纳滤去除某市河水中微污染物生产饮用水的可行性,并筛选生产饮用水的最佳纳滤膜,采用四种纳滤膜DESAL 51 HL、DESAL 5 DL、UTC-20和UTC-60处理河水,研究其去除COD、UV254吸收值以及硝酸盐等微污染物效率,考察纳滤过程中水通量变化.试验结果表明,四种膜对COD和具254nm吸收值的有机物去除率在50%～95%之间,UTC-20去除有机物效率最高.DESAL 51 HL、DESAL 5 DL和UTC 60对无机物截留率在22%～65%之间,而UTC-20达到93%.UTC-20对不同原水中硝酸盐的去除率均大于70%.在短时间纳滤实验中,存在着不可逆的水通量减少,有轻度膜污染发生.结论UTC-20适用于处理有机污染和硝酸盐复合污染的地表水源生产饮用水.