Amino acid sequence of a platelet-binding human anti-DNA monoclonal autoantibody

The complete amino acid sequences of the variable regions of the heavy and light chains of a human IgM monoclonal platelet-binding autoantibody have been determined. This antibody, HF2-1/17, produced by a human x human hybridoma prepared from lymphocytes of a patient with systemic lupus erythematosus and thrombocytopenia, is polyreactive with single-stranded DNA, synthetic polynucleotides, sulfated carbohydrates, and acidic glycolipids isolated from platelet membranes. The heavy chain is of the VHIII subgroup, and the light chain is of the VKI subgroup. The heavy chain is the expression product of the VH26 germline gene. The light chain bears significant homology to other immunoglobulins of known primary structure, including WEA, GAL, HAU, HK101, and DEE. These results suggest that HF2-1/17 may be an autoantibody derived with little or no modification from germline genes. A model of the antibody combining site suggests that arginine 24 and arginine 30 in the light chain (CDR1) interact with a surface defined by phosphate or sulfate groups of the antigen.     

辽西地区汉族成人的体型特征

目的:应用Heath-Carter法分析辽西地区汉族成人的体型特征,为体质人类学补充必要的资料。方法:于2002-09随机选择辽西地区20～82岁的汉族成人1002名(男490名,女512名)为测量对象。从20岁起,每5岁为一组,55岁以上为1个年龄组;每个年龄组按性别又分男、女两个小组,每小组测量人数不低于30名。由专人负责按Heath-Carter体型法进行指标测量和计算。10项测量指标分别是身高、体质量、上臂紧张围、小腿围、肱骨和股骨内外上髁间径、肱三头肌皮褶厚度、肩胛下皮褶厚度、髂前上棘皮褶厚度、腓肠肌皮褶厚度,测试数据按年龄、性别在微机中建立数据库。依次计算出各年龄组的内因子、中因子、外因子、体型图上的X,Y坐标值、身高体质量比、体型位置均数、两体型点间距离、体脂率和各类体型分布频数等。结果:1002名的各项指标均被测量,全部进入结果分析。①城市男女在内因子值(代表脂肪发育程度)方面占有明显的优势,中因子值(代表骨骼肌肉发育程度)方面和外因子值(代表身材相对瘦削程度)方面,城乡两组呈交替领先局面。提示汉族成人城市男女与农村男女相比,脂肪较发达,骨骼肌肉发育中等,身体线性度较差。②男性体型分布主要集中在偏中胚层的内胚层体型(53.5%),均衡内胚层体型(13.9%),偏外胚层的内胚层体型(9.1%),女性体型分布主要集中在偏中胚层的内胚层体型(62.8%),偏外胚层的内胚层体型(16.3%),均衡内胚层体型(13.7%)。体型频数分布提示汉族成年男女体型分布均较集中,以女性最为突出。③男女间体型相比,只有20～24岁和40～44岁年龄组男女间差异有显著性意义(P<0.05),其余各组差异无显著性意义。提示20～24岁为青春期的发育后期,男性得到充分的发育,而女性由于发育较早,发育已经停滞或缓慢。40～44岁女性更容易有脂肪沉积,而影响到其他有关体型的参数,出现男女差异。④辽西汉族城市成年人与农村成年人体型比较,内因子值城市成年男女均明显高于农村成年男女,中因子值和外因子值城乡较为接近,差异无显著性意义。结论:辽西地区城市成年男女骨骼、肌肉中等发达,体脂较多,身体线性度较差;农村成年男女,骨骼、肌肉较发达,体脂少于城市成人,身体线性度尚佳。     

Photoradiation models for the clinical ex vivo treatment of autologous bone marrow grafts

To assess the potential of photoradiation therapy for the in vitro purging of residual tumor cells from autologous bone marrow (BM) transplants, we studied normal marrow and tumor cell clonogenicity in response to different light-activated compounds by using the fluorescent dyes dihematoporphyrin ether (DHE) and merocyanine-540 (MC- 540). After photoradiation of cells with white light, both DHE and MC- 540 showed high cytocidal activity toward lymphoid and myeloid neoplastic cells but had a significantly lesser effect on normal granulocyte-macrophage (CFU-GM), erythroid (BFU-E), and mixed colony- forming (CFU-GEMM) progenitor cells. Acute promyelocytic leukemia (HL- 60), non-B, non-T, CALLA-positive acute lymphoblastic leukemia (Reh), and diffuse histocytic B cell lymphoma (SK-DHL-2) cell lines were exposed to different drug concentrations in combination with white light at a constant illumination rate of 50,000 lux. With DHE doses varying from 2.0 to 2.5 micrograms/mL and MC-540 concentrations of 15 to 20 micrograms/mL, clonogenic tumor cells could be reduced by more than 4 logs when treated alone or in mixtures with normal irradiated human marrow cells. However, preferential cytotoxicity towards neoplastic cells was highly dependent on the mode of light activation. MC-540 had no substantial effect on malignant lymphoid (SK-DHL-2) and myeloid (HL-60) cells and on normal marrow myeloid (CFU-GM) precursors when drug incubation was performed in the dark and followed by light exposure of washed cells. Equal doses of MC-540 (15 to 20 micrograms/mL) could preferentially eliminate tumor cells under conditions of simultaneous light and drug treatment (30 minutes at 37 degrees C). When using DHE (2.5 micrograms/mL), 29.3%, 46.8%, and 27.5% of normal marrow CFU-GM, BFU-E, and CFU-GEMM, respectively, were spared after sequential drug and light exposure of cells, whereas simultaneous treatment reduced both normal (CFU-GM) and neoplastic cells below the limits of detection. In summary, our results indicate the usefulness of various photoradiation models for the ex vivo treatment of leukemic and lymphomatous bone marrow autografts.     

Detection of hepatitis B virus in plasma using flow cytometric analyses of polymerase chain reaction-amplified DNA incorporating digoxigenin-11- dUTP

Blood donations are routinely screened by multiple serologic assays for antigens/antibodies associated with infection by blood-borne viruses, including hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency viruses (HIV-1 and HIV-2), and human T-cell lymphotropic virus (HTLV-I and HTLV-II). A direct detection of these viruses would be more effective for the prevention of transfusion- transmitted infections than the indirect measurement of the variable host immune response to these agents. Because the polymerase chain reaction (PCR) for viral gene amplification offers the most sensitive and direct means of detecting viruses in blood, we have developed a nonisotopic PCR procedure for the detection of HBV, chosen as a prototype. The problems, common to previously described PCR methods, of nucleic acid extraction and inhibition of the PCR by plasma proteins were overcome by isolation of HBV from plasma by means of 450-microns polystyrene beads covalently coated with monoclonal antibody to the Pre- S1 region of the viral envelope protein. Detergent lysis and proteinase K digestion of the immunocaptured virions isolated from plasma released the HBV DNA. A modified PCR-amplification protocol, incorporating digoxigenin-labeled dUTP in the amplified gene products followed by hybridization with a specific biotinylated oligonucleotide probe bound to streptavidin-coated 2.8-microns magnetic beads, allowed flow cytometric analyses of HBV-specific PCR products by means of antibodies to digoxigenin labeled with fluorescein isothiocyanate. The endpoint serial dilutions of pedigreed human plasma samples containing chimpanzee infectious dose (CID50) of 10(7) for adw and CID50 of 10(7.5) for the ayw subtypes were compared in repeated testing of PCR products by our immunoreactive bead (PCR-IRB) assay. HBV DNA was consistently detected in a 5 x 10(-10) dilution of each sample. In testing 20 coded specimens of blood donors, with or without serologic markers of HBV infection, the PCR-IRB was specific and more sensitive than the PCR analyses by slot blot hybridization with radioactive probe. The PCR-IRB assay can be adapted for simultaneous detection of multiple blood-borne viruses by an automated flow cytometric analysis system.     

Prevalence of Sarcopenia and Its Impact on Postoperative Outcome in Patients With Crohn's Disease Undergoing Bowel Resection

Background: Sarcopenia has been proposed to be a prognostic factor of outcomes for various diseases but has not been applied to Crohn's disease (CD). We aimed to assess the impact of sarcopenia on postoperative outcomes after bowel resection in patients with CD. Materials and Methods: Abdominal computed tomography images within 30 days before bowel resection in 114 patients with CD between May 2011 and March 2014 were assessed for sarcopenia as well as visceral fat areas and subcutaneous fat areas. The impact of sarcopenia on postoperative outcomes was evaluated using univariate and multivariate analyses. Results: Of 114 patients, 70 (61.4%) had sarcopenia. Patients with sarcopenia had a lower body mass index, lower preoperative levels of serum albumin, and more major complications (15.7% vs 2.3%, P = .027) compared with patients without sarcopenia. Moreover, predictors of major postoperative complications were sarcopenia (odds ratio [OR], 9.24; P = .04) and a decreased skeletal muscle index (1.11; P = .023). Preoperative enteral nutrition (OR, 0.13; P = .004) and preoperative serum albumin level >35 g/L (0.19; P = .017) were protective factors in multivariate analyses. Conclusion: The prevalence of sarcopenia is high in patients with CD requiring bowel resection. It significantly increases the risk of major postoperative complications and has clinical implications with respect to nutrition management before surgery for CD.