Comparison of numerical models for computing underwater light fields

Seven models for computing underwater radiances and irradiances by numerical solution of the radiative transfer equation are compared. The models are applied to the solution of several problems drawn from optical oceanography. The problems include highly absorbing and highly scattering waters, scattering by molecules and by particulates, stratified water, atmospheric effects, surface-wave effects, bottom effects, and Raman scattering. The models provide consistent output, with errors (resulting from Monte Carlo statistical fluctuations) in computed irradiances that are seldom larger, and are usually smaller, than the experimental errors made in measuring irradiances when using current oceanographic instrumentation. Computed radiances display somewhat larger errors.

[Subtyping of GC globulin in human semen stain]

The group-specific component (GC) is an alpha 2 globulin with high genetic polymorphism in serum. There is also a little amount of GC in human semen. Pflug and Potsch-Schneider independently carried out GC subtyping of human semen stain with immobilized pH gradient gel isoelectric focusing (IPGIF) followed by ELISA in 1988. We report a new method there to subtype GC in human semen stains. First, the GC globulin was separated by polyacrylamide gel isoelectric focusing with pH 4.2-4.9 Pharmalyte. Then, it was immunoblotted to cellulose acetate membranes. Finally, the protein bands were shown by ELISA using horseradish peroxidase-linked secondary antibody system. All the 17 semen stains of volunteers were subtyped successfully. This method is easy to learn and convenient for applying in case work.

Increases in glomerular eicosanoid production in rats with bilateral ureteral obstruction are mediated by enhanced enzyme activities of both the cyclooxygenase and 5-lipoxygenase pathways

Glomeruli isolated from rats with bilateral ureteral obstruction (BUO) of 24 hr duration produced significantly greater amounts of prostaglandin (PG) E2, 6-keto-PGF1 alpha, thromboxane B2, and leukotriene B4 than glomeruli isolated from sham-operated control (SOC) rats. To examine the mechanisms underlying the greater production of eicosanoids by glomeruli isolated from rats with BUO, we measured the activities of enzymes related to eicosanoid formation such as cyclooxygenase, 5-lipoxygenase, PGE2 isomerase, and PGI2 and thromboxane synthase in glomeruli isolated from SOC rats and rats with BUO. Glomeruli isolated from rats with BUO had a significantly increased activity of cyclooxygenase with de novo synthesis of this enzyme and a markedly augmented activities of PGE2 isomerase and both PGI2 and thromboxane synthases relative to glomeruli isolated from SOC rats. Similarly, the activity of membrane-bound 5-lipoxygenase, the active location of this enzyme, was significantly greater in glomeruli isolated from rats with BUO than in glomeruli isolated from SOC rats. Thus, BUO of 24 hr duration enhances the glomerular production of eicosanoids via the activation of enzymes in both the cyclooxygenase and 5-lipoxygenase pathways.

Analysis of heavy metals in mouse uterine secretion by X-ray microanalysis

A method for the detection of heavy metal ions in the uterine secretion of the mouse was tested. Mice received an intravenous injection of lead, and beads of an analytical grade resin, Chelex 100, were deposited in the uterine lumen to absorb heavy metals present in the secretion. X-ray microanalysis of the flushed beads showed that lead was present in a dose-related way in the uterine secretion of mice that had received 0.05, 0.1, or 0.15 mg lead per g body weight. Thus, the technique allows quantitative analysis of lead in the uterine secretion. The amount of lead present in the secretion decreased with time after the application of lead.

[Studies on laxative function of maren soft capsule]

The experimental results show that the Maren soft capsule can increase the amount and weight of the stool of normal mice and model mice with dry stool, promote the advanced percentage of charcoal powder in the small and large intestines of mice, enhance the movement of the smooth muscle of isolated ileum of guinea pigs under physiological conditions or low temperature, as well as strengthen the intestinal movement in rabbits.

[Growth type of colorectal cancer invasion of the proper muscle in relation to DNA ploidy and distribution of PCNA]

In order to elucidate the biological characteristics of colorectal cancer invading the proper muscle, we analyzed DNA ploidy and PCNA labeling index. The growth patterns were divided into three types; those accompanied by intramucosal polypoid growth (PG+), those with non-polypoid growth (PG-), and those ranging between PG+ and PG- (PG+/-). The relationship of DNA ploidy to lymphatic vessel permeation and recurrence was also discussed. The results were as follows: 1) Growth types bore no relation to DNA ploidy and distribution of PCNA. 2) In aneuploidy cancer, it showed a high incidence of lymphatic vessel permeation. A trend of lymphatic metastasis was also observed. Aneuploidy cancer showed a poor prognosis compared with diploidy cancer.

Application of Raney nickel to measure adducts of styrene oxide with hemoglobin and albumin

Adducts of styrene 7,8-oxide (SO) with the blood proteins, Hb and albumin (Alb), were measured following treatment of the proteins with Raney nickel (Ra-Ni) to cleave 2-phenylethanol, which was subsequently assayed. Internal standards were prepared by modifying Hb and Alb with 4-methyl-SO to produce similar adducts. In a preliminary experiment with human blood, which had been modified with [14C]SO in vitro, it was determined that Ra-Ni released 6% of the total binding to globin and 76% of the total binding to Alb. Since Ra-Ni primarily cleaves covalently-bound sulfur species, this suggests that much more binding to human serum Alb occurred at a free cysteine residue than to human Hb. The overall rate of reaction of SO at 37 degrees C in vitro had a half-time of 0.70 h in human blood and of 0.36 h in blood from Sprague-Dawley rats. Adducts of SO with Hb and Alb were measured following SO modification of blood from humans and rats in vitro at 37 degrees C. Slopes of the linear relationships between adduct level and SO concentration allowed the following second-order rate constants [(L/mol of protein)/h] to be estimated: rat Hb, 72; human Hb, 2.4; rat Alb, 63; human Alb, 32. These rate constants show that intrinsic reactivity of SO toward the cysteine residue of human Hb is much lower than that of rat Hb or of Alb from either species. Adducts of Hb and Alb were also measured following administration of both SO and styrene to rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Production of polyclonal antibodies against 1,1'-ethyliden bis[L-tryptophan] (EBT), a potential contaminant causing eosinophilia-myalgia syndrome (EMS)

Eosinophilia-myalgia syndrome (EMS) is thought to be caused by the intake of contaminated L-tryptophan products. 1,1'-Ethyliden bis[L-tryptophan] (EBT) is one of the contaminants in the L-tryptophan products and is thought to be a possible cause of EMS. In the present study we report that anti-EBT antibodies are generated by immunizing rabbits with the low molecular weight substance, EBT (molecular weight 434). These antibodies may be available tools for elucidating the mechanisms responsible for the outbreak and/or development of EMS.

An electric model with time varying resistance for a pneumatic membrane blood pump

To investigate the effects of an artificial heart and cardiac assist device on the cardiovascular system and determine the proper control method, an electrical model is an effective tool. An electric model with time varying resistance is proposed to represent a pneumatic membrane blood pump, by which the resistance of the valves in the pump is a function of time. The model is consistent over the whole cardiac cycle, and the important transitional processes between systole and diastole are considered. The calculated results based on this model are compared with the experimentally measured waveforms of the corresponding state-variables of a loaded pump, and the model parameters estimated using the least-squares criterion are compared with the measured physical values of corresponding functional parts. Results showed that this electric model is capable of representing a pneumatic membrane pump with quite satisfactory accuracy. They also showed that the transitional property of the valve resistance has a significant influence on the output characteristics of the pump.

Characterization of G-proteins in rat glomeruli

G-proteins in rat glomeruli were examined using bacterial toxin-catalyzed ADP-ribosylation and specific immunoblots. ADP-ribosylation catalyzed by cholera and pertussis toxin demonstrated the existence of Gs and Gi proteins in the glomerular membranes. Immunoblots further revealed two types of Gs alpha (45 and 52 kDa), Gi alpha 1 and/or Gi alpha 2 (40-41 kDa), Gi alpha 3 (40 kDa) and G beta (35-36 kDa) but not Go alpha in the membranes of the glomeruli. The predominant subspecies of Gs alpha was a 52 kDa protein. However, detectable amounts of G-proteins did not exist in cytosolic extracts of the glomeruli. We conclude that several subspecies of Gs and Gi proteins are present in rat glomerular membranes.

Instrumented parallel bars for three-dimensional force measurement

This paper describes the modification and instrumentation of standard parallel bars to allow for the measurement of applied forces on both horizontal bars in three dimensions. This measurement system has been used in the development and evaluation of functional electrical stimulation (FES) devices for standing and gait restoration in paralyzed patients. Real-time measurement of forces applied by the upper body of the patient to the parallel bars is of use in the evaluation of FES stimulation patterns (or automatic controllers of stimulation). Such measurements are useful in the redesign of stimulation patterns and/or stimulation controllers.

Activation of CD8+ T cells by allogeneic class II-deficient B-cell lines derived from patients with bare lymphocyte syndrome

The major histocompatibility complex (MHC) class II antigens (Ags) are known to carry the major stimulating determinants of the primary mixed lymphocyte reactions (MLR). We investigated the mechanism of generating HLA class I-directed alloreactive T-cells in primary MLR. With the use of class II-deficient EBV-transformed B-lymphoblastoid cell lines (B-LCLs) derived from patients with bare lymphocyte syndrome (BLS), we have demonstrated in the present study that class I disparity alone can trigger primary MLR in the absence of exogenous IL-2. The CD8+ T cells were primary MLR-responsive cells, and the CD4+ T cells seem to play no role in primary MLR when class II alloantigens are not involved in stimulation. Addition of autologous macrophages did not influence the primary MLR response. The primary MLR was completely blocked by anti-class I or anti-CD8 antibodies but not by anti-class II or anti-CD4 antibodies. The MLC-generated CD8+ T cells exhibited cytolytic activity as well as proliferative responses. The proliferative response of the CD8+ T cells was specifically directed against class I antigens, demonstrated by proliferative assays; and the helper-independent CD8+ T cells were generated only when the activation of CD4+ T cells did not occur. This observation suggests that functional recruitment of T-cell receptor (TCR) repertoire is under active regulation, and the suppression of CD8+ T-cell helper recruitment appears to be dictated by the CD4+ T-cell subset. Further analysis of the primed T-cell specificities showed that alloreactivity of the CD8+ T cells was mostly accounted for by the HLA-B Ags.(ABSTRACT TRUNCATED AT 250 WORDS)