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1.
A phase I trial of a murine anti-ganglioside (GD2) monoclonal antibody (mAb) 14G2a was conducted in 14 neuroblastoma patients and 1 osteosarcoma patient to assess its safety, toxicity and pharmacokinetics in pediatric patients. The pharmacokinetics of mAb 14G2a were biphasic with at 1 2/ of 2.8±2.8 h and at 1 2/ of 18.3±11.8 h. In general,t 1 2/ was dose-dependent with a level of significance ofP=0.036, and it reached a plateau at doses of 250 mg/m2 or more. Overall the peak serum levels were dose-dependent atP<0.001. However, they demonstrated an abrupt increase between doses of 100 mg/m2 and 250 mg/m2. The latter two suggest a saturable mechanism for mAb elimination. In addition, peak serum concentrations were observed earlier at higher mAb doses, which indicates the achievement of a steady state. Thet 1 2/ of mAb 14G2a in children appears to be shorter than in adults. Furthermore, 2 patients demonstrated a considerable decrease int 1 2/ following retreatment with 14G2a. This was paralleled by high human anti-(mouse Ig) antibody levels. This study represents the first comprehensive analysis of murine mAb pharmacokinetics in children and will be useful in the future design of mAb therapy.This work was supported by grants from FDA, FD-R-000377 and NIH U10 CA 28439 and in part by a grant from the general Clinical Research Center program, MOI RR00827, of the National Center for Research Resources, National Institutes of Health. M. M. U.-F. and C.-S. H. were supported in part by a grant from the Children's Cancer Research Foundation, and R. A. R. was supported in part by NIH grant CA 42508  相似文献   

2.
M. Steinemann 《Chromosoma》1980,78(2):211-223
About half of the diploid genome of D. virilis is -heterochromatic (Heitz, 1934) and contains the satellite sequences found in isopycnic CsCl density gradients (Gall et al, 1971; Steinemann, 1976). The thymidine incorporation behavior of this material in the course of S phase was monitored by autoradiography. Labelled interphase nuclei show three types of labelling patterns, label exclusively confined to either eu- or -heterochromatin, and simultaneous labelling of both fractions. Using the fraction of labelled mitotic index method, the duration of the DNA-synthetic period, ts = 11.9 ± 4.3 h and G2 period, tG2 + 1/2M = 6.9 ± 3.8 h, were determined. On the assumption that the investigated brain cells belong to an exponentially growing cell population, the cell cycle is 22.9 h long and the G1 period lasts tG1=4.1 h. The a-heterochromatin begins to replicate later than euchromatin and continues alone after a phase of common replication of both fractions. Noteworthy is the asynchronous termination in the proximal -heterochromatic segments of different chromosomes. Within the S phase, the first 1 h of DNA replication is exclusively confined to euchromatin, followed by 8 h of replication in both eu- and -heterochromatin and terminated by 3 h of exclusive -heterochromatin replication. Thus euchromatin has a doubling time of about 9 h and -heterochromatin of about 11 h. The -heterochromatin of D. virilis is late and slow replicating.  相似文献   

3.
Lipid analogues and glycosylphosphati-dylinositol (GPI)-anchored proteins incorporated in glass-supported phospholipid bilayers (SBL) were coupled to small (30 nm diameter) fluorescent beads whose motion in the liquid phase was tracked by intensified fluorescence video microscopy. Streptavidin (St), covalently attached to the carboxyl modified surface of the polystyrene bead, bound either the biotinylated membrane component, or a biotinylated monoclonal antibody (mAb) directed against a specific membrane constituent. The positions of the beads tethered to randomly diffusing membrane molecules were recorded at 0.2 sec intervals for about l min. The mean square displacement () of the beads was found to be a linear function of diffusion time t, and the diffusion coefficient, D, was derived from the relation, (t) = 4Dt. The values of D for biotinylated phosphatidylethanolamine (Bi-PE) dispersed in an egg lecithin: cholesterol (80:20%) bilayer obtained by this methodology range from 0.05 to 0.6 m2/sec with an average of D = 0.26 m2/sec, similar to the value of D = 0.24 m2/sec for fluorescein-conjugated phosphati-dylethanolamine (Fl-PE) linked to St-coupled beads by the anti-fluorescein mAb 4-4-20 or its Fab fragment. These values of D are comparable to those reported for Fl-PE linked to 30 nm gold particles but are several times lower than that of Fl-PE in the same planar bilayer as measured by fluorescence photobleaching recovery, D = 1.3 m2sec. The mobilities of two GPI-anchored proteins in similar SBL were also determined by use of the appropriate biotinylated mAb and were found to be D = 0.25 and 0.56 m2/sec for the decay accelerating factor (DAF, CD55) and the human FcRIIIB (CD16) receptors, respectively. The methodology described here is suitable for tracking any accessible membrane component.This work was supported by National Institutes of Health grants 1R24 RR05272 and AI-24322.  相似文献   

4.
Elevated expression of tumour necrosis factor- (TNF-) is associated with adverse pregnancy outcome. This study has examined the expression of TNF- and its receptors (TNF-Rs) by mouse blastocysts and blastocyst outgrowths from day 4 to 9.5 of pregnancy and investigated the effects of elevated TNF- on the inner cell mass (ICM) and trophoblast cells of blastocyst outgrowths. RT-PCR demonstrated TNF- mRNA expression from day 7.5 to 9.5, TNF-R1 from day 6.5 to 9.5 and TNF-R2 from day 5.5 to 7.5 of pregnancy, and in situ hybridisation revealed the trophoblast giant cells (TGCs) of the early placenta as the site of TNF- expression. Day 4 blastocysts were cultured in a physiologically high concentration of TNF- (100 ng/ml) for 72 h to the outgrowth stage and then compared to blastocysts cultured in media alone. TNF--treated blastocyst outgrowths exhibited a significant reduction in ICM cells (mean ± SD 23.90±10.42 vs 9.37±7.45, t-test, P<0.0001) with no significant change in the numbers of trophoblast cells (19.97±8.14 vs 21.73±7.79, t-test, P=0.39). Within the trophoblast cell population, the TNF--treated outgrowths exhibited a significant increase in multinucleated cells (14.10±5.53 vs 6.37±5.80, t-test, P<0.0001) and a corresponding significant decrease in mononucleated cells (5.87±3.60 vs 15.37±5.87, t-test, P<0.0001). In summary, this study describes the expression of TNF- and its receptors during the peri-implantation period in the mouse. It also reports that elevated TNF- restricts ICM proliferation in the blastocyst and changes the ratio of mononucleated to multinucleated trophoblast cells. These findings suggest a mechanism by which increased expression of TNF- during trophoblast differentiation may be detrimental to pregnancy.This work was supported by the National Health and Medical Research Council of Australia  相似文献   

5.
For homogeneous hypercycles with 2, 3 or 4 substances the future behavior of its trajectories is easily understood, in fact any trajectory converges to an equilibrium point as t +. In this paper we study the descent of the trajectories, i.e. their behavior as t -. It turns out that this backward behavior is not as uniform as the forward behavior. In fact, depending on the initial points some -limit sets are singletons while others consist of certain edges of the state simplex.Work partially supported by Deutsche Forschungsgemeinschaft under grant number Au 66–1  相似文献   

6.
Wen  Zhao  Shuang-Lin  Dong 《Hydrobiologia》2003,492(1-3):181-190
Primary productivity, biomass and chlorophyll-a of size fractionated phytoplankton (<0.22 m, <3 m, <8 m, <10 m, <40 m, <64 m, <112 m and <200 m) were estimated in 6 ponds and 5 experimental enclosures. The results showed that the planktonic algae less than 10 m are important in the biomass and production of phytoplankton in saline–alkaline ponds. The production of size fractionated phytoplankton corresponding to <112 m, <10 m and <3 m in saline–alkaline ponds were 10.5 ± 6.6 , 8.6 ± 5.4 and 0.33 ± 0.1 mgC l–1 d–1, respectively. Mean community respiration rate was 1.80 ± 0.73, 1.69 ± 0.90 and 1.38 ± 1.12 mgC l–1 d–1, respectively. The average production of phytoplankton corresponding to micro- (10–112 m), nano- (3–10 m) and pico- (<3 m) were 1.61, 8.30 and 0.33 mgC l–1 d–1, respectively. The ratio of those to the total phytoplankton production was 15%, 79% and 3%, respectively. The mean respiration rate of the different size groups was 0.11, 0.31 and 1.38 mgC l–1 d–1; the ratio of those to total respiration of phytoplankton was 6%, 17% and 77%, respectively. The production of size-fractionated phytoplankton corresponding to <200 m, <10 m and <3 m in enclosures was 2.19 ± 1.63, 2.08 ± 1.75 and 0.22 ± 0.08 mgC l–1 d-1, respectively. Mean community respiration rates were 1.25 ± 1.55, 1.17 ± 1.42 and 0.47 ± 0.32 mgC l–1 d–1, respectively. The average production of phytoplankton corresponding to micro- (10–200 m), nano- (3–10 m) and pico- (<3 m) plankton was 0.11, 1.86 and 0.22 mgC l–1 d–1, respectively. The ratio of those to the total production of phytoplankton was 5%, 85% and 10%, respectively. The mean respiration rate of different size groups were 0.08, 0.72 and 0.46 mgC l–1 d–1, the ratio of those to total respiration of phytoplankton was 6%, 57% and 37%, respectively. The concentrations of chlorophyll-a of the phytoplankton in the corresponding size of micro- (10–112 m), nano- (3–10 m) and pico- (<3 m) plankton in the experimental ponds were 19.3, 98.2 and 11. 9 g l–1, respectively. The ratio of those to the total chlorophyll-a was 15%, 76% and 9%, respectively. The concentrations of chlorophyll-a of phytoplankton micro- (10–200 m), nano- (3–10 m) and pico- (<3 m) plankton in enclosures were 1.7, 34.3 and 3.0 g l–1, respectively. The ratio of those to the total chlorophyll-a was 4%, 88% and 8%, respectively.  相似文献   

7.
We have recently reported that administration of Pro T to DBA/2 mice before the inoculation of syngeneic L1210 leukemic cells prolonged the survival of these animals by (a) inducing tumoricidal peritoneal macrophages, (b) enhancing natural killer (NK) and inducing lymphokine-activated killer (LAK) activities in splenocytes and (c) inducing the production of interleukin-2 and tumor necrosis factor [Papanastasiou et al. (1992) Cancer Immunol Immunother 35:145; Baxevanis et al. (1994) Cancer Immunol Immunother 38:281]. In this report we demonstrate that Pro T , when administered simultaneously with L1210 tumor cells, is capable of generating in DBA/2 animals tumorspecific CD8+ cytotoxic T lymphocytes (CTL). The Pro T -induced CD8+ CTL lysed their syngeneic L1210 targets in a major histocompatibility complex (MHC)-restricted fashion since monoclonal antibodies (mAb) against the H-2Kd allelic product could inhibit the cytotoxic response. Mice receiving only Pro T developed non-MHC-restricted cytotoxic activity (NK, and LAK activities) whereas those receiving Pro T and L1210 tumor cells developed both MHC-restricted (CTL) and non-MHC-restricted cytotoxic activities and survived longer. The Pro T -induced CD8+ CTL activity was regulated by Pro T -induced L1210-specific syngeneic CD4+ cells. This was shown in two different ways: first, CD8+-cell-mediated cytotoxic responses against L1210 targets were associated with L1210-specific and MHC-restricted proliferative responses of syngeneic CD4+ cells and, second, CD4+ cells from mice that had received both Pro T and L1210 tumor cells could enhance in vitro the otherwise weak, MHC-restricted and L1210-specific cytotoxicity of syngeneic CD8+ cells from mice that had received only L1210 cells. Our data suggest that Pro T is capable of inducing nonspecific, as well as tumor-specific CTL responses in vivo. This is of importance since Pro T may prove to be useful in clinical protocols aimed at cancer immunotherapy.This work was supported by a CEC grant to Dr. M. Papamichail  相似文献   

8.
To enhance the use of cellobiose by a recombinant Sachharomyces cerevisiae, the expressed -glucosidase that hydrolyzes cellobiose was stabilized using a surface-display system. The C-terminal half of -agglutinin was used as surface-display motif for the expression of -glucosidase in the cell wall. The surface-displayed -glucosidase had a half-life time (t 1/2) of 100 h in acidic culture broth conditions, while secreted -glucosidase had a t 1/2 of 60 h. With such stabilization of -glucosidase, the surface-engineered S. cerevisiae utilized 7.5 g cellobiose l–1 over 60 h, while S. cerevisiae secreting -glucosidase into culture broth used 5.8 g cellobiose l–1 over the same period.  相似文献   

9.
We have studied the in vitro transfection of a plasmid DNA with the lacZ gene to HeLa-S3 cells and hemolysis in a red blood cell (RBC) suspension under pulsed ultrasound with duty cycles of 10, 20 and 30% using a digital sonifier at a frequency of 20 kHz and an intensity of 6.2 W/cm2 on the surface of a horn tip. Cultured HeLa-S3 cells in suspension were exposed to pulsed ultrasound for an apparent exposure time t from 0 to 60 s. HeLa-S3 viability decreased as a single exponential function of the total exposure time t=t with a common time constant =3.8 s for three duty cycles. Transfection was evaluated by counting the number of -galactosidase(-Gal)-positive cells relative to the total number of cells. Pulsed ultrasound provided an enhanced transfer of the -Gal plasmid to HeLa-S3 cells, 3.4-fold as compared with that in the case of the control. The optimal transfection efficiencies were 0.75, 0.80 and 0.74% near t= with =10, 20 and 30%, respectively. The number ratio of -Gal-positive cells to the surviving cells after exposure increased with t according to a modified logistic equation. The degree of hemolysis also increased exponentially with t at a time constant =0/ for the RBC suspension in physiological saline at a hematocrit concentration of 0.5% with 0=0.9 s. Thus the total exposure time for the optimal transfection efficiency was , that is, nearly four times of 0. Hemolysis in the RBC suspension may be a useful model for determining optimal transfection by pulsed ultrasound of various duty cycles.  相似文献   

10.
Summary The effect of cold and warm intermittent antegrade blood cardioplegia, on the intracellular concentration of taurine in the ischaemic/ reperfused heart of patients undergoing aortic valve surgery, was investigated. Intracellular taurine was measured in ventricular biopsies taken before institution of cardiopulmonary bypass, at the end of 30 min of ischaemic arrest and 20 min after reperfusion. There was no significant change in the intracellular concentration of taurine in ventricular biopsies taken after the period of myocardial ischaemia in the two groups of patients (from 10.1 ± 1.0 to 9.6 ±0.9mol/g wet weight for cold and from 9.3 ± 1.3 to 10.0 ± 1.3mol/g wet weight for warm cardioplegia, respectively). Upon reperfusion however, there was a fall in taurine in both groups but was only significant (P 0.05) in the group receiving cold blood cardioplegia (6.9 ± 0.8mol/g wet weight after cold blood cardioplegia versus 8.0± 0.8mol/g wet weight following warm blood cardioplegia). Like taurine, there were no significant changes in the intracellular concentration of ATP after ischaemia in the two groups of patients (from 3.2 ± 0.32 to 2.95 ± 0.43mol/g wet weight for cold and from 2.75 ± 0.17 to 2.62 ± 0.21mol/g wet weight for warm cardioplegia, respectively). However upon reperfusion there was a significant fall in ATP in both groups with the extent of the fall being less in the group receiving warm cardioplegia (1.79 ± 0.19mol/g wet weight for cold and 1.98 ± 0.27mol/g wet weight for warm cardioplegia, respectively). This work shows that reperfusion following ischaemic arrest with warm cardioplegia reduces the fall in tissue taurine seen after arrest with cold cardioplegia. Accumulation of intracellular sodium provoked by hypothermia and a fall in ATP, may be responsible for the fall in taurine by way of activating the sodium/taurine symport to efflux taurine.  相似文献   

11.
Summary The eye of the frilled sea hare,Bursatella leachi plei, expresses a circadian rhythm in the frequency of spontaneously occurring optic nerve impulses. The rhythm will free-run for at least 3 cycles in vitro (Fig. 2) and can be entrained by light cycles provided in vivo (Fig. 4 A). While bothBursatella andAplysia eyes contain circadian pacemakers the two rhythms differ in several respects: (1) the peak impulse frequency forBursatella eyes is only 96/h (±36 SD) compared with 247/h (±61 SD) forAplysia. (2) The ocular waveform of theBursatella rhythm exhibits a steep rise and fall from peak frequencies and lacks the delayed falling phase which creates a shoulder on the ocular waveform inAplysia (Fig. 2). (3) The in vitro free-running period of theBursatella ocular rhythm is 21.2 h (±0.6 SD) compared with 24.3 h (±0.9 SD) for theAplysia rhythm (Fig. 2). (4) The steady state phase angle for entrainment differs withBursatella eyes showing a median activity peak at +3 Z.T. compared with a medianAplysia peak at –1 Z.T. (Fig. 4).We also investigated the locomotor rhythm.Bursatella were found to be predominantly diurnal when exposed to LD, 1212 (Fig. 5A) and to exhibit anticipatory locomotor activity when maintained on LD), 915 (Fig. 6). The eyes appear to play a minor role, if any, in timing the locomotor rhythm. EyelessBursatella remained diurnal on LD, 915 and most animals continued to exhibit anticipatory behavior (Fig. 6). These results suggest that theBursatella eye plays a less prominent role than theAplysia eye in controlling locomotor behavior.Abbreviations DD constant darkness - LD 1212 24 h light cycles 12 h light, 12 h dark - EST Eastern Standard Time - Z.T. Zeitgeber Time We would like to thank L. Baird, W. Kilmartin and S. Wallace for help with animal maintenance, data presentation and photography. We also thank T. Breeden for our computer programs. This work was supported by NIH grant NS-15264 to G. Block.  相似文献   

12.
Successful application of stable-hydrogen isotope measurements (Df) of feathers to track origins of migratory birds and other wildlife requires a fundamental understanding of the correlation between Df and deuterium patterns in rainfall (Dp) over continental scales. A strong correlation between Dp and Df has been confirmed for birds and insects in North America, but not yet for other continents. Here, we compare Df data from resident European birds to new Dp basemaps for Europe. Three maps, representing growing-season and mean annual Dp estimates from an elevation-explicit, detrended interpolation model and growing-season Dp estimates from simple Kriging, all indicate that strong isotope gradients occur across Europe with a general depletion occurring in a northeast direction. The feather data, representing 141 individuals of 25 avian species from 38 sites, ranged from –131 to –38. Regression analysis showed that strong correlations existed between both mean annual and growing-season Dp estimated by detrended interpolation and Df of non-aquatic and non-corvid birds (r2=0.66 and 0.65, respectively). We also examined mean annual and growing-season 18Op vs. 18Of for our samples. Both oxygen regressions were similar (r2=0.56 and 0.57, respectively) but poorer than for deuterium. Our study reveals that D measurements of feathers from migratory birds in Europe may be used to track their origin and movements, and so provide a powerful investigative tool for avian migration research in Europe.  相似文献   

13.
The life cycles of two separate populations (colonies A and B) of the rabbit tick, Haemaphysalis leporis-palustris, were studied under laboratory conditions. Domestic New Zealand rabbits, Oryctolagus cuniculus, and wild rabbits, Sylvilagus brasiliensis, were used as hosts for ticks from colony B and only O. cuniculus rabbits were used as hosts for ticks from colony A. Developmental periods were observed in an incubator at 27±1°C and RH 90±5%. Larvae from colonies A and B fed for 8.0±3.7 days and 8.5±1.3 days, respectively, on O. cuniculus. On S. brasiliensis larvae from colony B fed for 7.2±1.3 days. Nymphs from colony A fed for 8.1±1.4 days on O. cuniculus and nymphs from colony B fed for 8.1±1.0 days on S. brasiliensis. Only one engorged nymph from colony B was recovered from O. cuniculus. Females from colony A fed for 20.9±5.9 days on O. cuniculus and females from colony B fed for 18.6±2.4 days on O. cuniculus and 18.7±3.7 days on S. brasiliensis. Engorged larvae from colony A required 13.7±3.7 days to molt while engorged larvae from colony B required 11.8±3.0 and 11.5±1.8 days to molt, after having fed on O. cuniculus and S. brasiliensis, respectively. Engorged nymphs from colonies A and B required 16.3±1.9 days and 14.7±1.4 days to molt, respectively. Engorged females from colonies A and B required 4–7 and 3–5 days, respectively, to start oviposition. Mean egg incubation periods lasted for 33–34 days. For ticks from colony B, host species accounted for significant differences (p<0.05) in larval and nymphal feeding periods, oviposition weights and CEIs. Significant differences (p<0.05) between the two colonies when ticks fed on O. cuniculus were observed for larval and nymphal feeding and premolt periods, engorged female and oviposition weights and conversion efficiency indexes (CEI). S. brasiliensis were always a more suitable host for H. leporis-palustris than O. cuniculus. Significantly more larvae and nymphs engorged and molted when fed on S. brasiliensis (p<0.001). Females fed S. brasiliensis were more successful to lay fertile eggs and showed the highest engorged and egg mass weights, and the highest CEIs. Data of H. leporis-palustris fed on wild rabbits (one of its natural host species) are reported for the first time.  相似文献   

14.
We examined the effects of fertilizer application, especially the effects of fertigation and types of fertilizer (inorganic and organic) on yields and 15N and 13C values of tomato (Lycopersicon esculentum Mill. cv. Saturn). Fertigation is a method in which an appropriate diluted liquid fertilizer is applied to the plants each time they are drip-irrigated. We developed a method of organic fertigation using corn steep liquor (CSL) as the liquid fertilizer, because it is an industrial byproduct of cornstarch manufacture and can be used very effectively. We compared fruit yield, mineral content, 15N value, and 13C value of tomatoes grown under three different fertilizer treatments, basal dressing: basal dressing with granular chemical fertilizer; inorganic fertigation: fertigation with liquid chemical fertilizer; and organic fertigation: fertigaion with CSL. Mineral contents of tomatoes grown with basal dressing were generally lower than those grown under either fertigation treatment. These results indicated that yields and mineral contents were influenced more by the method of fertilizer application than by whether the fertilizers were inorganic or organic. There were, however, significant differences in the 15N values of tomato fruits grown under different types of fertilizer applications, especially between inorganic and organic fertilizers. The 15N value of the chemical fertilizer used for basal dressing was 0.81 ± 0.45{}, that of the chemical fertilizer for fertigation was 0.00 ± 0.04{}, and that of CSL was 8.50 ± 0.71{}. The 15N values of the soils reflected the 15N values of the fertilizers. Moreover, the 15N values of the fruits corresponded to the 15N values of the applied fertilizers. The 15N values were 3.18 ± 1.34{} in the fruits grown with a basal dressing of chemical fertilizer, 0.30 ± 0.61 in those grown under inorganic fertigation, and 7.09 ± 0.68 in those grown under organic fertigation. On the other hand, although the 13C values in the soil also reflected the 13C values of the applied fertilizers, there was no significant difference in the 13C values of fruits among the different treatments. In conclusion, because the 15N values of fertilizers correlated well with those of the fruits, it may be possible to use 15N values as an indicator of organic products.  相似文献   

15.
    
The limited proteolytic pattern of transducin,G t , and its purified subunits with chymotrypsin were analyzed and the cleavage sites on the t subunit were identified. The t subunit in the GTPS bound form was cleaved into a major 38 kD fragment, whereas t -GDP was progressively digested into 38, 23, 21, and 15 kD fragments. The t subunit was not very sensitive to proteolytic digestion with chymotrypsin. The t subunit was not cleaved and only a small portion of t was digested into several fragments. In order to determine which proteolytic fragment of t still contained the carboxyl terminal region, chymotrypsinization was carried out usingG t previously32P-labeled at Cys347 by petrussis toxin-catalyzed ADP-ribosylation. The32P-label was mainly associated with the t subunit and a 15 kD fragment. The 23 and 21 kD fragments were not32P-labeled. Analysis of amino terminal sequences of 38, 21, and 15 kD proteolytic bands allowed the identification of the major cleavage sites. Chymotrypsin had two cleavage sites in the amino terminal region of t , at Leu15 and Leu19. Chymotrypsin removed 15–19 amino acid residues from the amino terminus of t , generating two peptides (38 kD) which comigrates in gel electrophoresis. Chymotrypsin also cleaved at Trp207 in a conformation-dependent manner. Trp207 of t -GTPS was resistant to proteolysis but t -GDP and the 38 kD fragments of t -GDP produced the 23 and 21 kD fragments, respectively, and a 15 kD fragment containing the carboxyl terminus. This proves that the environment of Trp207 changes when GTP or GTPS is bound, leading to its inaccessibility to chymotrypsin.  相似文献   

16.
Excessive oxidative stress is implicated in hepatic fibrogenesis. Extracts of Salvia miltiorrhiza (Sm) have been shown to protect cells against oxidative stress. In this study we investigated the in vitro and in vivo effects of Sm on hepatic fibrosis. A cell line of rat hepatic stellate cells (HSC-T6) was stimulated with transforming growth factor-1 (TGF-1). The inhibitory effects of Sm (50~400 g/ml) on TGF-1-induced -smooth muscle actin (-SMA) secretion and the mRNA expressions of fibrosis-related genes, including -SMA, connective tissue growth factor (CTGF), and tissue inhibitor of metalloproteinase-1 (TIMP-1), were assessed. Fibrosis was induced by dimethylnitrosamine (DMN) administration in rats. DMN-treated rats were randomly assigned to 1 of 4 groups: saline, Sm (20 mg/kg), Sm (100 mg/kg), or silymarin (100 mg/kg), each given by gavage twice daily for 5 weeks starting from the onset of DMN administration. Sm (200 and 400 g/ml) significantly inhibited TGF-1-stimulated -SMA secretion and the mRNA expressions of -SMA, CTGF, and TIMP-1 in HSC-T6 cells. Fibrosis scores of livers from DMN-treated rats with either a low (1.8 ± 0.2) or high (1.8 ± 0.1) dose of Sm, or silymarin (1.4 ± 0.2) were significantly reduced in comparison with DMN-treated rats receiving saline (3.1 ± 0.1). Hepatic collagen contents were also significantly reduced by either Sm or silymarin treatment. The mRNA expression levels of -SMA, TGF-1, and procollagen I were all attenuated in Sm- and silymarin-treated rats. Moreover, levels of plasma aspartate transaminase activities were reduced by Sm and silymarin treatment. In conclusion, our results show that Sm exerted antifibrotic effects in both HSC-T6 cells and in rats with DMN-induced fibrosis.  相似文献   

17.
The HLA-DRw6 haplotype of the class II major histocompatibility complex (MHC) antigens exhibits unusual complexity and cannot be uniquely typed serologically. The DR chains expressed by consanguineous homozygous DRw6 typing cells WT46 and WT52 were biochemically analyzed using three monoclonal antibodies (mAb) that recognize denatured DR chains. The results of isoelectric focusing and N-terminal sequencing demonstrate that each DRw6 B-cell line expresses two DR chains. Evidence of an exchange of mAb epitopes involving the two DR chains of one of these cell lines was obtained and may be explained by a recombinational mechanism involving reciprocal exchange of genetic segments of the DR chains, one of which may encode the putative DRw6 chain and the other the chain carrying the MT2 allotypic determinant. Since a recombinational hot spot has been shown to occur uniquely in the mouse MHC within the E gene, the occurrence of a recombination within the human homolog, DR(MT2) , could reflect some specific feature of this MHC region. Comparison of the DR chains of the WT46 and WT52 cell lines with those of a third DRw6 cell line, LB, suggests that two alleles of MT2 occur.Abbreviations used in this paper IEF isoelectric focusing - mAb monoclonal antibody - MHC major histocompatibility complex - SDS-PAGE sodium dodecyl sulfate-polyacrylamide gel electrophoresis  相似文献   

18.
The mangrove killifish Rivulus marmoratus was reared at 25°±1°C and 17ppt salinity from 0 to 100 days after hatching (DAH), and its early development was described by examining growth and morphometric parameters, meristic characters (vertebral and fin-ray counts), bone-cartilage development, and pigmentation. Growth was isometric for preanal length, head length, snout length, body depth, pectoral-fin length, dorsal-fin length, anal-fin length, and caudal-peduncle depth. Negative allometric growth was observed in eye diameter and gape size. Meristic counts (mean±SD) for vertebrae (34.2±0.4) and dorsal- (8.6±0.5), anal- (11.4±0.5), and caudal-fin rays (30.2±0.8) were complete at 0 DAH (n=5), whereas pectoral-fin rays and pelvic-fin rays were complete by 30 DAH (14.5±0.4, n=5) and 60 DAH (4.2±0.8, n=5). Full ossification of meristic elements proceeded in the following sequence: vertebrae (by 30 DAH), caudal-, dorsal-, and anal-fin rays (by 60 DAH), pectoral-fin rays (between 60 DAH and 100 DAH), and pelvic-fin rays (by 100 DAH). Both morphological characters and meristic counts indicate that this species can be considered to be a juvenile after 9.8mm in standard length (20 DAH).  相似文献   

19.
Summary Twenty mutants isolated from Latisail, Jhingasail and Pankaj varieties of rice (Oryza sativa L.) were screened for two aspects of nutritive quality, namely crude protein content and distribution pattern of protein in the endosperm. Observations revealed a wide variation for both characters, and while there was no consistent association between protein content and test grain weight, which varied between varieties, a positive correlation between protein content and grain sterility was noted. In a few mutants protein distribution was observed to be varied and showed a similarity to optimum milling characteristics.  相似文献   

20.
Summary Oligomerization of 5-TMP in water pools entrapped by dodecyl-ammonium chloride surfactant aggregates in benzene: hexane in the presence of dicyanodiimide at temperatures ranging from 21°–72° resulted in the formation of linear and cyclic oligonucleotides containing up to pentamers. Effects of temperature, time and surfactants have been examined. Rate constants for the formation of oligomers have been determined at five different temperatures. These data afforded values of H = 11.8 ± 1.9 Kcal mole–1, S=–53 6 e.u. and G = 27.4 4.0 Kcal mole–1. Prebiotic significance of these results are discussed.  相似文献   

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