放射免疫沉淀法与酶联免疫吸附试验检测抗-LSP的双盲对照研究

研究表明,抗肝细胞膜特异性脂蛋白抗体(抗-LSP)在病毒性肝炎,特别是慢性活动性肝炎的发病机理中可能起较重要的作用。关于抗-LSP的检测,国内外文献中多     

A Mr 90 000 surface polypeptide of Trypanosoma cruzi as a candidate for a Chagas' disease diagnostic antigen

Trypanosoma cruzi (Peru strain) trypomastigotes and epimastigotes were biosynthetically labeled with [35S]methionine, and the proteins were analyzed by two dimensional polyacrylamide gel electrophoresis (2D-PAGE). 2D-PAGE analysis of the trypomastigotes showed a complex array of polypeptides with distinct clusters at Mr 88 000-92 000, isoelectric point (pI) 5.6-6.0, and Mr 72 000-76 000, pI 5.6-5.8. 2D-PAGE analysis of the epimastigotes did not show the cluster of polypeptides at Mr 90 000. When the trypomastigote lysate was reacted with sera from either mice or humans chronically infected with T. cruzi, 10-50 polypeptides were immunoprecipitated. Five of these polypeptides were recognized by all sera tested. However, of these polypeptides, only three, two of Mr 90 000 and one of Mr 150 000, can be identified by immunoreaction of [35S]methionine-labeled live parasites as surface proteins of T. cruzi trypomastigotes. 125I-iminobiotinylated surface proteins isolated from T. cruzi trypomastigotes were immunoprecipitated with the same series of sera as described above. Chagasic sera immunoprecipitated an antigen of Mr 90 000. The [35S]methionine and 125I-labeled Mr 90 000 polypeptides were not immunoprecipitated with sera from individuals infected with Leishmania donovani, Leishmania braziliensis, Leishmania tropica or Leishmania mexicana. These data indicate that a surface polypeptide of Mr 90000, pI 5.8-5.9 is a viable candidate for a Chagas' disease diagnostic antigen.     

In vivo release of met-enkephalin in the cat brain

Push-pull cannulae were implanted into the globus pallidus (anterior part), the caudate nucleus (medio-dorsal part) and the substantia nigra of halothane-anaesthesized cats to study the characteristics of the in vivo release of met-enkephalin. Met-enkephalin was measured by radioimmunoassay (sensitivity: 0.1 pg) and identified by Bio-Gel P₂ chromatography and high-pressure liquid chromatography. Under resting conditions, met-enkephalin was detected in perfusates from these three regions; in the globus pallidus, the rate of spontaneous release of met-enkephalin was 5–6 times higher than that observed in the caudate nucleus and the substantia nigra. The local application of either an excess (60 mM) of K⁺ or of glutamate (10 μM) produced a marked increase in the rate of met-enkephalin release both from the globus pallidus and the caudate nucleus. Further analyses in the globus pallidus indicated that the depolarizing agents, veratridine (50 μM) and batrachotoxin (0.1 μM), produced a large increment in the rate of met-enkephalin release; this effect was completely prevented by the local application of tetrodotoxin (2 μM).The chemical (with 60 mM K⁺ or 10 μM glutamate), electrical or mechanical stimulation of the dorsomedial part of the caudate nucleus failed to significantly alter the rate of met-enkephalin release in the ipsilateral globus pallidus, in spite of the high sensitivity of enkephalinergic nerve terminals in the globus pallidus itself to local stimuli. This observation argues against the existence of a major caudatopallidal enkephalinergic pathway.     

Development of radioimmunoassay for bullfrog thyroid-stimulating hormone (TSH): effects of hypothalamic releasing hormones on the release of TSH from the pituitary in vitro

A bullfrog (Rana catesbeiana) thyroid-stimulating hormone (TSH) beta-subunit (TSHbeta) antiserum was produced by employing a C-terminal peptide synthesized on the basis of the amino acid sequence deduced from bullfrog TSHbeta cDNA. Immunohistochemical studies revealed that the bullfrog adenohypophyseal cells that immunologically reacted with the anti-bullfrog TSHbeta corresponded to those positively stained with an antiserum against human (h) TSHbeta. The antiserum was used for the development of a specific and sensitive radioimmunoassay (RIA) for the measurement of bullfrog TSH. The sensitivity of the RIA was 0.75+/-0.07ng TSH/100microl assay buffer. The interassay and intraassay coefficients of variation were 7.6 and 5.3%, respectively. Several dilutions of pituitary homogenates of larval and adult bullfrogs, or medium in which bullfrog pituitary cells were cultured, yielded dose-response curves that were parallel to the standard curve. Bullfrog prolactin, growth hormone, luteinizing hormone, follicle-stimulating hormone, and alpha-subunit derived from glycoprotein hormones did not react in this assay. Immunoassayable TSH in the pituitary culture medium was confirmed to exist in the form of TSHbeta coupled with the alpha-subunit by an immunoprecipitation experiment using the TSHbeta antiserum and an alpha-subunit antiserum. TSH released from pituitary cells into the medium was also confirmed to possess a considerable activity in stimulating the release of thyroxine from the thyroid glands of larval bullfrogs in vitro.The effects of hypothalamic hormones such as mammalian gonadotropin-releasing hormone (mGnRH), ovine corticotropin-releasing hormone (oCRH), and thyrotropin-releasing hormone (TRH) on the release of TSH by dispersed anterior pituitary cells of the bullfrog larvae and adults were also studied. CRH markedly stimulated the release of TSH from both adult and larval pituitary cells. Both TRH and GnRH moderately stimulated the release of TSH from adult pituitary cells but not from the larval cells. This is the first report on the development of an RIA for amphibian TSH, which has provided the direct evidence that the release of TSH from the amphibian pituitary is enhanced by the hypothalamic releasing hormones such as CRH, TRH, and GnRH.     

Utilizing reamer irrigator aspirator (RIA) autograft for opening wedge high tibial osteotomy: A new surgical technique and report of three cases

INTRODUCTION

The lateral closing wedge high tibial osteotomy (HTO) was popularized by Coventry in the 1960s. In the 1990s the medial opening wedge osteotomy gained popularity because it could achieve greater valgus correction and it did not require dissociation of the fibula from the tibia, an important consideration when treating varus knees with lateral and posterolateral ligament deficiencies (Noyes’ double-varus and triple-varus knees). However, it has the disadvantage of requiring bone graft to fill bony defects. Recently, the reamer-irrigator-aspirator (RIA; Synthes, Paoli, PA) system was developed, and as a result of this procedure, a large amount of usable autogenous bone graft can be collected safely for use. To our knowledge, there is no published series combining opening wedge HTO with the use of RIA obtained autogenous bone graft.

PRESENTATION OF CASE

We present a novel technique in which a series of three patients underwent opening wedge HTO using ipsilateral, retrograde femur RIA graft to fill the bone defect. All patients had satisfactory clinical and radiologic outcomes following the new technique at latest follow up.

DISCUSSION

Opening wedge high tibial osteotomy is a well-documented and accepted orthopedic procedure, however, has the disadvantage of requiring varying amounts of bone graft. Traditionally, iliac crest or tricortical allograft have been the grafting modalities of choice, however both have inherent drawbacks to their use. In our series, the use of RIA autograft is a safe and reliable harvest technique for high tibial osteotomy, providing abundant and quality autogenous bone graft.

CONCLUSION

All three of our patients achieved radiographic union with high clinical patient satisfaction without any major complications. We feel this novel technique is a safe and acceptable operative solution grafting opening wedge osteotomies about the knee.     

老年人服用人参皂甙前后血清FT3,FT4含量的RIA

采用放射免疫分析（ＲＩＡ）方法，对２０例老年人服用人参皂甙前后血清ＦＴ３、ＦＴ４含量进行测定，并与正常成人对照。结果老年组ＦＴ３、ＦＴ４含量为正常低值，明显低于成年对照组（Ｐ＜０．０５与Ｐ＜０．０１）；老年组ＦＴ３、ＦＴ４男女无显著差异；成年组ＦＴ３男高于女（Ｐ＜０．０５），ＦＴ４女高于男（Ｐ＜０．０１）；老年组服药后ＦＴ３略有增加，ＦＴ４增加明显，与服药前比较差异显著（Ｐ＜０．０５），仍低于成年对照组，差异显著     

Electroradioimmunoassay (ERIA): a new type of double antibody radioimmunoassay based on electroimmunodiffusion

A modified type of a sensitive and reliable double antibody radioimmuno-assay is described. The modification consists of the separation of free and bound antigen, which is achieved by electroimmunodiffusion in agarose gel. The second antibody is incorporated in a gel zone near the electrophoretic starting point. Electrophoretic separation is performed on specially devised perspex plates in a routine immunoelectrophoresis unit within 2 h. The system was tested with α₁-acid glycoprotein in serum and in neutralized gastric juice. The least detectable concentration was 1 ng/ml. The precision coefficient was 0.02–0.035.     

Immunoassay of human plasma apolipoprotein B

A specific and precise double antibody immunoassay for human plasma apolipoprotein B (apoB) was developed and applied in normolipidemic and hyperlipidemic subjects. The intra-assay coefficient of variation was ca. 9%. The distributions of total apoB and low density lipoprotein (LDL) apoB in a randomly selected, healthy, fasting population (n = 349) was slightly skewed with a mean total apoB of 81 mg/100 ml and LDL apoB of 72 mg/100 ml. The 90th percentile cutoffs for total apoB and LDL apoB were 106 and 97 mg/100 ml, respectively. Regarding total apoB, women showed a statistically significant increase (r = 0.463, p less than 0.001) with age (30-65) and an average annual increment of plasma apoB of 1.1 mg/100 ml. In contrast, men showed only a slight increase of apoB from the 4th to 5th decade, with an average annual increment of 0.7 mg/100 ml (r = 0.201, 0.02 less than p less than 0.05). Similarly, regarding LDL apoB, women showed an increase of 1.0 mg/100 ml/year from the 4th to 7th decade (r = 0.501, p less than 0.001), whereas men's LDL apoB did not increase significantly with age (r = 0.114, 0.2 less than p less than 0.3, for ages 30-49). Six of ten normal young subjects showed essentially no physiological variation in fasting apoB levels over a 10-wk period, whereas four had a variation of ca. 5% or less. LDL apoB represented ca. 90% of the total apoB in normolipidemic and type II plasma samples (86% in type IV samples) but only 68% in type III plasmas (n = 7). The ratios of LDL cholesterol-LDL apoB were similar for the random and hyperlipoproteinemic groups, ranging from a high of 1.8 for type IIa to a low of 1.5 for type IV. The ratio of cholesterol to apoB was significantly elevated (p less than 0.002) in the d less than 1.006 fraction of the type III plasma samples compared to the random and type II groups.     

Ghrelin levels in young children with Prader-Willi syndrome

OBJECTIVE: To explore the hypothesis that high ghrelin levels contribute to obesity in Prader-Willi syndrome (PWS), we assessed whether the increased levels observed in older persons with PWS exist in very young children, before the onset of hyperphagia. STUDY DESIGN: We measured ghrelin levels in nine children with PWS (17-60 months of age) and eight healthy control subjects of equivalent body mass index (BMI), age, and sex. RESULTS: PWS and control groups had equivalent BMI (16.8 +/- 1.4 vs 16.1 +/- 0.9 kg/m(2), respectively; P = .24), age (37.8 +/- 15.4 vs 50.3 +/- 17.7 months; P = .14), and sex. PWS and control groups also had equivalent fasting levels of total ghrelin (787 +/- 242 vs 716 +/- 135 pg/mL, respectively; P = .24), bioactive ghrelin (102 +/- 35 vs 91 +/- 23 pg/mL; P = .45), insulin, and glucose. Ghrelin correlated negatively with BMI among controls (r = -0.760, P = .029) but not PWS (r = 0.015, P = .97). CONCLUSIONS: Children <5 years of age with PWS, who had not yet developed hyperphagia or excessive obesity, had normal ghrelin levels, in contrast with the hyperghrelinemia of older, hyperphagic people with PWS. It is possible that ghrelin levels increase suddenly before hyperphagia develops.     

Cotinine excretion (tobacco smoke biomarker) of smokers and non-smokers: comparison of GC/MS and RIA results

With a validated GC/MS method, the tobacco smoke biomarker cotinine has been estimated in urine for 148 non-smokers (male; 43±13 years; median 5.0 μg/g creatinine; 95^th percentile 104 μg/g) and 96 smokers (male; 39±12 years; 1002 μg/g; 2993 μg/g). For a subgroup of 50 persons, the GC/MS results were compared with those by a commercially available radio immunoassay. Both methods identified the same persons as non-smokers and smokers, respectively, and were closely related. For smokers, the relationship was distinctly closer than for the non-smokers (r=0.90, p<0.001, n=14 vs. r=0.41, p<0.02, n=36). The RIA values were 2.4times (smokers) and 2.9times (non-smokers) higher than the GC/MS results. This was probably caused by the cross reactivity of the RIA antibodies against other urinary nicotine metabolites, e.g. trans-3′-hydroxycotinine, and has to be taken into account to correctly compare results of studies obtained with different analytical techniques and for choosing cut-off points to discriminate between active smokers and non-smokers or between non-smokers with higher or lower exposure to environmental tobacco smoke.