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1.
《The International journal of biochemistry》1993,25(5):781-788
- 1.1. Immunotrap assays that can measure the activities of urokinase-type plasminogen activator (uPA) and its inhibitors (PAIs) were characterized.
- 2.2. Both human plasma and mouse macrophages in culture were found to contain much higher inhibitor activity than uPA-like activity.
- 3.3. The balance between pro- and anti-flbrinolytic activities was quantitatively changed in the murine macrophages after the injection of thioglycollate. uPA-like materials were synthesized by the macrophages and secreted to the conditioned medium continuously, while PAI activity was unchanged during the same time period.
2.
《Comparative biochemistry and physiology. A, Comparative physiology》1989,92(2):263-266
- 1.1. Carp red cells were treated with drugs that affect the cell membranes. The water content of the cells and the accumulation of cAMP in the cells were measured in normoxia and in hypoxia using non-stimulated and adrenergically stimulated cells.
- 2.2. WGA, DIDS + CCCP and A23187 increased the water content of nonstimulated normoxic cells.
- 3.3. In hypoxia ouabain and DIDS + CCCP increased the water content but cytochalasin B, NPM, DIDS, CCCP and A23187 + CA2+ abolished the hypoxia-induced swelling.
- 4.4. Any membrane perturbation induced some cAMP formation, Sophora and Anquilla lectins being most potent.
- 5.5. Also in adrenergically stimulated cells, membrane perturbation generally increased cAMP formation.
- 6.6. However, cAMP accumulation diminished in cells treated with cytochalasin B, CCCP and DIDS + CCCP.
- 7.7. The adrenergic swelling of carp red cells was reduced in normoxia by DIDS. NPM and CCCP increased the adrenergic swelling in normoxia to hypoxic level.
- 8.8. In hypoxia WGA and Anquilla lectin decreased the swelling.
3.
《Comparative biochemistry and physiology. C: Comparative pharmacology》1988,89(2):449-457
- 1.1. Simultaneous measurement of calcium fluxes in brown trout, at low external [Ca] (20 μ mol 1−1), provided evidence of active uptake of Ca from the medium.
- 2.2. At pH 4.5, calcium influx was inhibited and efflux was stimulated.
- 3.3. Cd and Mn, but not Al, at concentrations within the ranges found in acid waters experiencing fish population decline, inhibited calcium influx. Efflux was unaffected.
- 4.4. Cd and Mn stimulated sodium influx and efflux.
4.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1976,53(2):157-160
- 1.1. Conjugation of Tetrahymena enhanced the incorporation of glycine into the nuclear fraction by 500%.
- 2.2. Incorporation of glycine into the microsomal supernatant was augmented by almost 500% by conjugation.
- 3.3. Mitochondrial incorporation was stimulated nearly 3-fold in the conjugating strains while the incorporation of glycine into the microsomes was enhanced approximately 2.5 times.
- 4.4. In the whole cell, glycine incorporation was increased nearly 2-fold by conjugation.
- 5.5. Strong nuclear involvement was indicated by elevated metabolic activity and incorporation of glycine into RNA and DNA.
- 6.6. Stimulation of the metabolism of Tetrahymena by cell communication suggests that the contents of a cell can have a synergistic effect on another cell.
- 7.7. Augmentation of the biosynthetic capacities of cells by fusion is a demonstration of the dominant role of the cell membrane in the regulation and control of cells.
- 8.8. Enhancement of biosynthesis of nuclear proteins in conjugating strains of cells indicates that fusion gives rise to the synthesis of new protein from previously existing protein or protein procursors.
- 9.9. The specific activities of the subcellular fractions after the incorporation of glycine into 2 separated starved strains of Tetrahymena followed the usual pattern of nucleus less than whole cells, whole cells less than mitochondria, mitochondria less than microsomes, but with the microsomal supernatant being much greater than that of the microsomes.
5.
《The International journal of biochemistry》1987,19(11):1127-1131
- 1.1. Inorganic phosphate (Pi) was absorbed rapidly by suspension-cultured cells of Catharanthus roseus which had previously been cultured in Pi-free Murashige Skoog medium.
- 2.2. The intracellular levels of ATP, ADP and 5-phosphoribosyl-l-pyrophosphate (PRPP) increased markedly during the 24 hr which followed the addition of Pi (1.25mM).
- 3.3. Availability of PRPP in vivo, estimated by the measurement of nucleotide synthesis from [8-14C]adenine, was also increased by addition of Pi.
- 4.4. Only a 20% increase in the maximum catalytic activity of PRPP synthetase was observed in extracts of cells, prepared 24 hr after addition of Pi.
- 5.5. In contrast to results for mammalian PRPP synthetase, the activity of PRPP synthetase, partially purified from Catharanthus roseus, was inhibited by concentration of Pi greater than 5mM.
- 6.6. The mechanisms involved in the increased availability of PRPP and the synthesis of adenine nucleotides in the plant cells cultured in Pi-containing medium are discussed.
6.
《Comparative biochemistry and physiology. A, Comparative physiology》1978,59(3):407-410
- 1.1. Insulin stimulated intracellular accumulation of α-amino-isobutyric acid (AIB) in kidney cortex slices from young lambs and piglets.
- 2.2. The effect was similar in the absence or presence of glucose.
- 3.3. The induction of the stimulatory effect on renal AIB transport was blocked by cycloheximide. an inhibitor of protein synthesis.
- 4.4. The insulin stimulation of intracellular AIB accumulation is due to an increased influx and not to a reduced efflux of AIB.
- 5.5. Analysis of transport kinetics for AIB showed that insulin increased Vmax but did not change Km.
- 6.6. It is concluded that insulin stimulates uptake of certain neutral amino acids into kidney cortex cells in young animals.
- 7.7. The effect on renal amino acid transport appears to be mediated through increased synthesis of a membrane carrier.
7.
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(4):939-945
- 1.1. Myo-inositol is transported in chicken small intestine by a mediated route with an apparent Km of 0.1 mM and by a diffusion mechanism.
- 2.2. The mediated route is susceptible to inhibition by sugars, though sugars are not transported by this process, nor is myo-inositol transported by the sugar transport system.
- 3.3. Myo-inositol influx is inhibitable by phlorizin, sulfhydryl reagents, removal of Na+ from the incubation medium, and preloaded sugar; it can be stimulated by theophylline.
- 4.4. The ability to absorb this nutrient varies greatly between individual animals.
8.
《Comparative biochemistry and physiology. A, Comparative physiology》1979,62(2):363-370
- 1.1. The unidirectional transepithelial fluxes of L-phenylalanine, β-methyl-D-glucoside and sodium ions across emusculated sheets of tench mid-intestine were determined in flux chambers.
- 2.2. No net sodium flux was detectable, but phenylalanine was preferentially transferred from the mucosal to the serosal fluid.
- 3.3. There was also a net movement of β-methyl-glucoside towards the serosal medium, but it was much smaller than that of phenylalanine.
- 4.4. This transport was accompanied by an accumulation of each substrate from the mucosal medium into the tissue to a similar level and against a concentration gradient.
- 5.5. The poor transfer of the monosaccharide into the serosal medium could therefore be attributed to a low permeability of the baso-lateral membrane of the enterocyte for this substance.
- 6.6. The influx of L-phenylalanine and of β-methyl-d-glucoside into the epithelial cells of tench midintestine was examined by incubating slices of emusculated intestine in radioactively-labelled solutions of the substrate for 2 min.
- 7.7. The steady-state uptake was assessed after similar incubations lasting 45 min.
- 8.8. Phenylalanine influx obeys the Michaelis-Menten equation with a Km of 2.9 mM and is dependent on the presence of sodium ions in the incubation medium.
- 9.9. β-Methyl-glucoside influx reveals the same characteristics with a Km of 2.0 mM but a considerably lower Vmax; in addition, it is inhibited by galactose.
- 10.10. The influx of both substrates is reduced by harmaline, which also inhibits the uptake of radioactive sodium by this preparation.
- 11.11. The steady-state uptake of β-methyl-glucoside is also inhibited by ouabain and by 2.4-dinitrophenol.
- 12.12. These results suggest that the mechanisms for sodium-dependent influx of monosaccharides and neutral amino-acids in the tench intestine are similar to those found in mammalian tissues.
- 13.13. The principal difference appears to involve the release of monosaccharides across the baso-lateral membrane of the enterocyte.
9.
《Comparative biochemistry and physiology. A, Comparative physiology》1991,98(2):439-443
- 1.1. Embryonic and posthatch turkey skeletal muscle development was compared in in vitro studies using clonal-derived embryonic myoblasts and satellite cells.
- 2.2. Although population doubling times were similar between the two lines (25.4 hr for satellite cells and 26.4 hr for embryonic myoblasts), embryonic myoblasts consistently began log phase growth 24 hr earlier than satellite cells.
- 3.3. Differentiation (fusion) of embryonic myoblasts was maximized by 36 hr in Dulbecco's Modified Eagle's Medium containing 1% horse serum compared with 72 hr for satellite cells.
- 4.4. When administered a serum-free medium which supports proliferation of turkey satellite cells, embryonic myoblasts differentiated to form myotubes.
10.
《The International journal of biochemistry》1986,18(7):589-594
- 1.1. The properties of ATPase activity were studied with the cells at the early stationary phase of Saccharomycopsis fibuligera.
- 2.2. Optimal pH for the activity was approximately 7.
- 3.3. The activity was stimulated by Mg2+.
- 4.4. The activity was inhibited by NaF, DCCD, oligomycin, NaN3, NaVO3, or PCMB but not inhibited by ouabain.
11.
《The International journal of biochemistry》1993,25(2):239-245
- 1.1. High levels of type I collagen mRNA and [3H]proline incorporation into collagenase digestable protein by MC3T3-E1 cells were detected during the first 7 days of culture, after which they declined.
- 2.2. Type I collagen gene expression was stimulated by TGF-β in the early culture stage when the collagen gene expression was fully functioning.
- 3.3. However, these stimulatory effects disappeared at the differentiation stages. Although collagen gene expression was stimulated by TGF-β (2.0 ng/ml) in early culture, collagen synthesis in medium was not.
- 4.4. This study shows that collagen synthesis and collagen gene expression were affected by the state of differentiation in MC3T3-E1 cells and that the rate of stimulation by TGF-β in collagen gene expression decreased over time in culture.
12.
《Comparative biochemistry and physiology. B, Comparative biochemistry》1981,68(1):133-139
- 1.1. Babesia hylomysci has an aminopeptidase and an acid endoprotease
- 2.2. The amino-peptidase has properties very similar to the aminopeptidase in Plasmodium yoelii nigeriensis and P. chabaudi.
- 3.3. The acid endoprotease is specific towards haemoglobin and practically has no action on bovine serum albumin.
- 4.4. In mouse normal red blood cells we find an acid protease having physico-chemical properties similar to the enzyme present in B. hylomysci extracts.
- 5.5. The similarity of electrophoretic velocity between acid protease in B. hylomysci and non-infected red blood cells leads us to think that the acid protease of parasitic extracts comes from the host-cell.
- 6.6. The proteolytic system of Babesia and Plasmodium are similar.
13.
《The International journal of biochemistry》1976,7(3-4):165-171
- 1.1. Resting spores, germinated spores, and mycelium of Penicillium roqueforti actively decarboxylate (β-ketolauric acid to 2-undecanone. The rate of 2-undecanone formation increases as resting spores germinate and activity is highest in mycelium.
- 2.2. Glucose stimulated the formation of 2-undecanone by resting spores but had no effect on activity in mycelium.
- 3.3. The enhanced methyl ketone production in spores is attributed to the progressive increase in activity of β-ketoacyl decarboxylase as spores germinated.
- 4.4. Cell-free extracts obtained from mycelium contained heat stable and heat labile species of β-ketoacyl decarboxylase.
- 5.5. Optimum pH for the conversion of β-ketolaurate to 2-undecanone was 6.5–7.0.
- 6.6. Biphasic substrate saturation curves and a discontinuous slope in Arrhenius plot for β-ketoacyl decarboxylase suggested the existence of two species of ketoacyl decarboxylase in P. roqueforti.
14.
《Comparative biochemistry and physiology. A, Comparative physiology》1982,71(3):363-368
- 1.1. Phascolopsis gouldi, the commonly studied sipunculan of the Woods Hole area, Massachusetts, can tolerate a salinity range from about 45% seawater to at least 100% SW, with literature records extending to about 160% SW. There was no survival at 40% SW.
- 2.2. Over this salinity range, P. gouldi is an osmotic and ionic conformer.
- 3.3. The osmotic and sodium concentrations of the coelomic fluid are the same as that of the medium; the chloride concentration is about 9% less than that of the medium; the potassium concentration is about 30% higher.
- 4.4. Analysis of water content regulation by two different approaches shows that P. gouldi does have a limited ability for volume regulation, restricted to salinities higher than 58% SW.
- 5.5. P. gouldi is not a “simple osmometer”.
15.
《Comparative biochemistry and physiology. A, Comparative physiology》1993,104(3):471-477
- 1.1. Studies characterizing glucose transport in the frog sartorius were performed.
- 2.2. For nonstimulated and stimulated muscles, intracellular 2-deoxyglucose exceeded 2-deoxyglucose-6-phosphate at 15 min, showed little further increase, and was maintained below the extracellular concentration for 2 hr.
- 3.3. Accumulated 2-deoxyglucose-6-phosphate did not inhibit glucose transport.
- 4.4. Unlike in adipocytes, basal and stimulated 2-deoxyglucose transport showed no difference in sensitivity to N-carbobenzoxy-glycyl-l-phenylalaninamide.
- 5.5. Phenylarsine oxide blocked contraction-enhanced 2-deoxyglucose uptake.
- 6.6. These results suggest that the glucose transporter of the sartorius exhibits auto-regulation, and that basal transport is not regulated by the same process as in adipocytes.
16.
《The International journal of biochemistry》1981,13(5):591-602
- 1.1. A choriolytic enzyme was isolated from the hatching medium of the pike, Esox lucius.
- 2.2. The enzyme is defined as hatching enzyme.
- 3.3. The molecular weight of the enzyme is 24,000.
- 4.4. The enzyme is a glycoprotein containing 2% carbohydrate.
- 5.5. Its isoelectric point is 6.5.
- 6.6. The pH optimum is around pH 8.
- 7.7. The enzyme molecule contains two disulfide bonds but no free cysteine.
- 8.8. Inhibitor studies and metal analysis show that the enzyme is a zinc-metalloprotease.
17.
18.
《Comparative biochemistry and physiology. A, Comparative physiology》1982,71(4):599-604
- 1.1. Microscolex phosphoreus (Acanthrodrilidae: Oligochaeta) is a small bioluminescent earthworm with a broad distribution throughout the world.
- 2.2. In response to adverse stimuli it exudes a luminescent fluid from the mouth and along the body wall which originates in the coelome and contains large (27.1 ± 4.2 μm) granule filled cells.
- 3.3. Similarly to the other species examined so far, the luminescence system is found associated with the isolated granule filled cells; it is stimulated to emit by hydrogen peroxide, Diplocardia longa luciferin and D. longa luciferase; and exhibits a broad, unimodal bioluminescence spectrum (λmax = 538 nm).
- 4.4. The spectrum of the bioluminescence is matched by fluorescence which is associated with these same cells.
- 5.5. The spectrum of the soluble extract has a considerably altered spectrum with some indications of a similar, but more complex, alteration in the spectroscopy of the fluorescent component.
- 6.6. These results are discussed in comparison with other investigations of M. phosphoreus bioluminescence and the general common features of earthworm bioluminescence.
19.
《The International journal of biochemistry》1994,26(2):155-162
- 1.1. Pseudomonas aeruginosa phospholipase C from culture supernatants of bacteria grown in high-Pi basal salt medium with choline, as the sole carbon and nitrogen source, was purified by precipitation with 70% saturation ammonium sulfate in the presence of celite.
- 2.2. The PLC activity was eluted of this mixture by the use of a reverse gradient of 70-0% ammonium sulfate.
- 3.3. The peak containing the PLC activity revealed a single protein after SDS-PAGE.
- 4.4. The method could also be applied to purify PLC produced in a low-Pi complex medium. The resultant preparation was not homogeneous.
- 5.5. The molecular weight for both PLC preparations was about 70 kDa.
- 6.6. Both PLC used phosphatydilcholine and sphingomyelin as substrates, displayed hemolytic activity an exhibited an apparent KM of 25 mM for p-nitrophenylphosphorylcholine.
- 7.7. They were not inhibited by 1% sodium deoxycholate but were 30% inhibited by 1% Triton X-100.
- 8.8. 2% sodium dodecylsulfate and 1% tetradecyltrimethylammonium bromide inhibited the PLC from the HPl-BSM plus choline but not the enzyme from the LPl-CM.
20.
《Molecular & cellular proteomics : MCP》2019,18(5):876-891
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- •Three novel Conodipines P1-3 in the injected venom of Conus purpurascens.
- •Conodipines P1-3 have consensus catalytic characteristics of sPLA2.
- •We determined multiple modification sites in Conodipines P1-3.
- •Evaluated the activity of Conohyal-P1 by a MS-based method.