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681.
Ninety-two hospitals in a three-state mid-Atlantic region were surveyed to determine their policy toward obtaining written informed consent for transfusion and to examine the content of written consent documents and the process by which consent is obtained. Of 81 hospitals responding, 50 (62%) required written informed consent. Hospitals with fewer than 200 beds were more likely to require written informed consent. The attending physicians had responsibility for obtaining consent in 28 (57%) of 49 institutions, most often on the day or evening before surgery. Twenty-seven of 48 forms mentioned complications: hepatitis in 80 percent, human immunodeficiency virus infection in 46 percent, nonhemolytic reactions in 32 percent, and hemolysis in 25 percent. Alternatives to allogeneic transfusion were mentioned infrequently; eight hospital forms listed autologous transfusion options and only two mentioned designated donation. The reading level required to comprehend 34 consent forms submitted was grade 14.6, which has been attained by only 23 percent of the adult United States population. Although the majority of respondent institutions require written informed consent, those forms, per se, do not document that the fundamental tenets of informed choice have been applied to the decision to transfuse blood. 相似文献
682.
Band 3 (anion-exchange protein 1-[AE1]) is the major integral membrane protein of human erythrocytes and links the membrane to the underlying cytoskeleton via high-affinity binding to ankyrin. It is unclear whether other cytoskeletal proteins participate in strengthening the ankyrin-band 3 linkage, but a putative role for protein 4.2 (P4.2) has been proposed based on the increased osmotic fragility and spherocytic morphology of P4.2-deficient red blood cells (RBCs). The present study was designed to investigate the hypothesis that P4.2 has a direct role in strengthening the band 3-cytoskeleton linkage in human RBCs, by measuring independent features of this interaction in normal and P4.2- deficient RBCs. The features examined were the rotational mobility of band 3 assayed by time-resolved phosphorescence emission anisotropy (TPA), and the extractability of band 3 by octyl-beta-glucoside, the latter being a nonionic detergent that selectively extracts only band 3 that is not anchored to the cytoskeleton. We find that the amplitude of the most rapidly rotating population of band 3 (correlation time, approximately 30 to 60 microseconds) is increased 81% and 67% in P4.2- deficient ghosts (P4.2NIPPON and band 3MONTEFIORE, respectively) compared with control ghosts. The amplitude of the intermediate speed rotating population of band 3 (correlation time, approximately 200 to 500 microseconds) is increased 23% and 8% in P4.2-deficient ghosts (P4.2NIPPON and band 3MONTEFIORE, respectively) compared with control ghosts, at the expense of the slowly rotating component (correlation time, approximately 2,000 to 3,000 microseconds, amplitude decreased 43% and 39% in P4.2NIPPON and band 3MONTEFIORE, respectively) and immobile component (immobile on this experimental time scale; amplitude decreased 26% and 10% in P4.2NIPPON and band 3MONTEFIORE, respectively) of band 3. These results demonstrate that P4.2 deficiency partially removes band 3 rotational constraints, ie, it increases band 3 rotational mobility. The nonionic detergent octyl-beta-glucoside, which does not disturb band 3-cytoskeleton associations, ie, it extracts only band 3 that is not attached to the cytoskeleton, extracted 30% and 61% more band 3 from P4.2NIPPON and band 3MONTEFIORE ghost membranes, respectively, compared with control ghosts. The octyl-beta-glucoside ghost extracts from both P4.2-deficient phenotypes were enriched in band 3 oligomeric species (tetramers, higher-order oligomers, and aggregates) compared with controls. Since band 3 oligomers selectively associate with the cytoskeleton, these results are consistent with a weakened band 3-cytoskeleton linkage in P4.2-deficient RBC membranes. P4.2 deficiency does not affect band 3 anion transport activity, since uptake of radiolabeled sulfate was similar for control and P4.2- deficient RBCs. Thus, we propose that P4.2 directly participates in strengthening the band 3-cytoskeleton linkage. 相似文献
683.
A case of sarcomatoid carcinoma of the skin 总被引:1,自引:0,他引:1
HS Inaloz†§ RS Ayyalaraju† PJA Holt† P Laidler‡ 《Journal of the European Academy of Dermatology and Venereology》2003,17(1):59-61
We describe the histological and immunocytochemical findings of an exophytic cutaneous tumour with mixed features of atypical fibroxanthoma (AFX) and basal cell carcinoma (BCC). A 73-year-old woman presented with a rapidly growing tumour measuring 35 mm in diameter and 10 mm in height on the left forearm. The tumour was excised and histology revealed a biphasic tumour with a pleomorphic spindle cell component and an associated tumour composed of discrete islands of atypical basaloid cells with peripheral palisading consistent with BCC. The two tumours merged into each other at one point. The spindle cell tumour showed a positive immunocytochemical reaction to fibrohistiocytic marker of KP-1 (CD68) and a negative immunocytochemical reaction to AE1/AE3, CAM5.2, S-100 and HMB-45, features consistent with AFX. Immunocytochemistry of the basaloid tumour showed a positive reaction to epithelial markers AE1/AE3 and CAM5.2, and a negative reaction to S-100, HMB-45 and KP-1 (CD68). To date, 15 cases of primary cutaneous carcinosarcoma have been reported in the literature. It has been postulated that these tumours may originate from undifferentiated progenitor cells capable of producing multiple cell lines. 相似文献
684.
685.
Effects of hypericin encapsulated on Pluronic F127 photodynamic therapy against triple negative breast cancer 下载免费PDF全文
Maria V F de SouzaCristiane S Shinobu-MesquitaLyvia E F MeirellesNatália L MariGabriel B CésarRenato S GonçalvesWilker CaetanoEdilson DamkeVânia RS SilvaGabrielle MZF DamkeMarcia E L Consolaro 《Asian Pacific journal of cancer prevention》2022,23(5):1741-1751
Objective: Breast cancer (BC) currently has no effective treatment especially for the highly aggressive and metastatic triple negative breast cancer (TNBC). Here, we investigated the antitumoral and antimigratory effects of hypericin (HYP) encapsulated on Pluronic F127 (F127/HYP) photodynamic therapy (PDT) against TNBC cell line MDA-MB-231 compared to a nontumorigenic human breast ductal cell line (MCF-10A). Methods: The phototoxicity/cytotoxicity was assessed by MTT assay, long-term cytotoxicity by clonogenic assay, cell uptake, subcellular distribution, and cellular oxidative stress by fluorescence microscopy, cell death with annexin V-FITC/propidium iodide, PDT mechanism using sodium azide and D-mannitol, and cell migration by wound-healing assay. Results: The treatment promoted phototoxic effect on tumor cell line in a dose-dependent and selective manner. Internalization of F127/HYP was efficient and accumulation occurred in the endoplasmic reticulum and mitochondria, resulting in cellular oxidative stress mainly by the type II mechanism, induced by necrosis. Furthermore, F127/HYP decreased colony formation and reduced the cell migration ability in MDA-MB-231 cells. Conclusion: Our results suggest a potentially useful role of F127/HYP micelles as a platform for HYP delivery to more specifically and effectively treat TNBC. 相似文献
686.