Open-heart surgery in Jehovah''s Witnesses: experience in a Canadian hospital

Jehovah's Witnesses have religious belief precluding the use of blood. Few centers have attempted open-heart surgery bound by such strictures; as a result, availability of therapy for such patients has been limited. Many groups that have extensive experience with hemodilution for cardiopulmonary bypass have noted that these procedures can often be done with little or no use of blood. Our experience with 21 adult patients is presented in this paper.     

Interactions of the components of the prothrombinase complex

1. Acetylcholinesterase (acetylcholine hydrolase, EC 3.1.1.7) of house-fly head tissue was solubilized as a 7.4-S form by autolysis for 80-100 h at 25 degrees C and pH 8.0. 2. The autolysed enzyme was purified by affinity chromatography, firstly on Con-A-Sepharose and subsequently on m-trimethylammoniumaniline-Affi-Gel 202. This sequence permitted overall purification yields of approx. 50% of the solubilized enzyme. 3. The 7.4-S purified enzyme was essentially homogeneous on polyacrylamide gel electrophoresis, and its specific activity coincided with the highest previously reported for fly-head acetylcholinesterase. 4. Polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate and beta-mercaptoethanol revealed two major polypeptide components of molecular weight 82 000 and 59 000. Each of these polypeptides contained diisopropylphosphofluoridate-binding sites, as shown with [3H] diisopropylphosphofluoridate. 5. The results suggest a strong structural similarity between fly-head acetylcholinesterase and the purified electric eel enzyme.     

Role of the pituitary gland in adaption of the fish Tilapia mossambica (Peters) to contrasting backgrounds

The fish Tilapia mossambica were exposed for 30 days to continuously illuminated black or white backgrounds. When compared with the controls the black-adapted fish showed multiplication of the melanophores with a maximal dispersion of the melanosomes. The white background induced blanching of the fish because of depletion of the melanophores and aggregation of the melanosomes. The treatment evoked major changes in the pars intermedia cells. Of these, the amphiphils were stimulated in the black-adapted and regressed in the white-adapted fish indicating that these cells secrete melanophore stimulating hormone. The cyanophils showed depressed activity in the black-adapted fish, but in the white-adapted animals they were stimulated. These alterations suggest the elaboration of a melanophore concentrating hormone by the cyanophils. Regressive effects were also recorded in the gonadotrops and gonads of the experimental T. mossambica.     

Experimental evaluation of three single-particle dissolution models

The dissolution of the 60-85-mesh fraction os recording, flow-through dissolution apparatus equipped with a dissolution cell; it was particularly suitable for kinetic analysis of multiparticulate systems. By using a time-scaling approach, experimental data are compared with theoretical calculations to evaluate, quantitatively, which of three single-particle dissolution models best describes the data and how well the multiparticulate kinetics can be explained mathematically. The nonspherical tolbutamide particles are replaced in the calculations by a hypothetical system of spherical particles that appears to be log-normally distributed. This procedure permits the calculation of the intrinsic dissolution profile, considering both size distribution and particle shape effects.     

异味掩盖剂的研究理论与应用

<正> 在食品的生产过程中,人造甜味剂的使用可能给某些产品带来苦味或不良后味,防腐剂如山梨酸盐和苯甲酸盐的添加也可能导致苦味的出现;此外,过度处理产品或使用营养疗效添加剂和咖啡因也可能引致其他异味的出现。这些异味可能是很突出的。食物的苦味可能来源于天然存在的苦味化合物,或由于保存及加工处理中发生的化学反应所致。因此,异味掩盖剂的开发一直是行业的重点研究课题。     

Donor cell induced CD69 expression and intracellular IL-2 and IL-4 production by peripheral blood lymphocytes isolated from kidney transplant recipients

Flow cytometry assays, which measure CD69 activation and intracellular cytokine production, have been used to measure peripheral blood lymphocyte (PBL) responses to in vitro antigen exposure. In the present study, we show that, in healthy individuals and immunosuppressed kidney transplant recipients, CD69 expression and intracellular cytokine production by peripheral blood T cells compare favorably to thymidine uptake as a measure of PBL response to alloantigen in mixed leukocyte culture (MLC). Heparinized whole blood from 23 healthy individuals was incubated for 24-48 h with 3rd party allogeneic monocytes; blood from twelve kidney transplant recipients was incubated with monocytes from their kidney donor and with monocytes from unrelated individuals. The percentage of T cells expressing surface CD69 or intracellular IL-2 or IL-4 was determined by 3-color flow cytometry. We identified 5 donor-specific response patterns in our kidney transplant group. One transplant recipient was hyporesponsive; his cells did not express CD69 or produce IL-2 in response to either donor or 3rd party allogeneic cells. All other transplant recipients expressed CD69 and IL-2 in response to 3rd party allogeneic cells. Two had no response to donor cells (donor-specific hyporesponsiveness), three had donor-specific anergy (CD69 expression without cytokine production in response to donor cells), five had a donor-specific Thl response (CD69 expression and IL-2 production in response to donor cells), and one had a donor-specific Th2 response (CD69 expression and IL-4 but not IL-2 production in response to donor cells). Rapid measures of donor-specific hyporesponsiveness such as CD69 activation antigen expression and intracellular cytokine production may prove valuable in monitoring lymphocyte function and aid in the long-term management of kidney transplant recipients.     

低聚果糖:促进钙吸收的食品配料

<正> 骨质疏松症是指未能通过膳食摄入足够钙质以补充身体的自然流失而导致骨折的发生,其罹患率在全世界已有增加的趋向。研究防止这种健康问题将为社会和经济带来一定的效益,何况现今愈来愈多的人们已通过媒体及医生等途径对骨质疏松症有更深入的认识。食品工业界对于这种市场变化,通过开发钙强化食品作出了积极的回应,纷纷推出一些有助于钙吸收的食品。 一般来说,人体大约30％(青年期高达50％)摄入的钙会被体内吸收并贮存于骨骼中,但到老年期骨质会逐渐流失,故若在青年期(人体骨质生长高峰约至30岁)能使骨质良好地生长,     

Analytic treatment of resolution precision in electronically collimated SPECT imaging involving multiple-interaction gamma rays

The widely applied single-interaction analytic expression characterizing the energy resolution component of the angular resolution precision for an electronically collimated point source is extended to include multiple-interaction Compton scatter sequences as well as sequences terminated by photoelectric absorption. The analytic formulation is developed using the statistical variance of the mean for components comprising composite, multivariate resolution precision estimators. It is demonstrated that enhanced resolution precision in the incident interaction scatter angle is attained when use is made of information from multiple interactions. An improvement in the resolution precision of up to approximately 40% is observed for triple Compton scatter. Comparison of the analytic estimates with Monte Carlo/chi-square results shows good agreement.     

The effect of x-ray contrast media on the amount of thromboxane and prostacyclin in the blood of man and rats in vivo and in vitro

The in vivo and in vitro effects of radioopaque agents such as bilignost, iodamide, and triombrast on blood thromboxane B2 (TxB2) and prostacyclin levels were studied in man and rats. These radioopaque agents were demonstrated to increase prostacyclin levels and to decrease TxB2 in the plasma by 40%, as evidenced by urography when given in vivo (1-2 g/kg) and in vitro (2.5.10(-2) M and 2.5.10(-3) M).