Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Culture-produced subendothelium (SE) has been prepared from cultured porcine aortic endothelial cells (ECs) by a rapid freeze-thaw, ice-shearing method. En face preparations of this in situ SE material are essentially free of intact or damaged cells and cell debris and consisted of an extensive meshwork of microfibrillar and amorphous material. Washed porcine platelets reacted extensively with this SE material and were associated with the SE as single adherent platelets, single spread platelets, and varying-sized platelet aggregates or 'microthrombi'. Platelet aggregates were associated only with the damaged or frayed edges of the SE, and the platelets had undergone extensive SE-induced contraction and degranulation, as indicated by transmission electron microscopy. Platelet-SE interaction was affected by pH, calcium, platelet concentration, rapid shaking and exposure time. Platelet-SE interaction was significantly enhanced by the addition of 0.1-1% citrated plasma or purified porcine F.VIIIR:WF. Pretreatment of the SE with thrombin, elastase, neuraminidase or hyaluronidase had no effect on platelet-SE interaction, whereas pretreatment with pepsin, plasmin, trypsin, alpha-chymotrypsin or collagenase decreased or completely abolished all platelet-SE interaction. Extraction of the SE with various solutions (high salt, detergents, etc.) had no effect on platelet-SE interaction, only solutions containing sodium dodecyl sulfate completely abolished all platelet-SE interaction.
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PMID:Culture-produced subendothelium. I. Platelet interaction and properties. 680 25

Production and characterization of Haemophilus pleuropneumoniae hemolysin were investigated by using 5 serotype 2 strains. The hemolysin was produced in chicken meat-infusion broth medium both in stationary and in shaking cultures. In stationary culture, hemolytic activity against horse RBC reached maximum at postincubation day 5 (at the late stage of stationary phase), and the activity was maintained at the same level for 2 days thereafter. The hemolytic activity of shaking culture reached a maximum at postincubation hour 9 (at the early stage of logarithmic-growth phase), gradually decreased, and disappeared at postincubation day 2. The hemolysin was shown to be an extracellular product of the bacterial cells. The RBC of horses, rabbits, and sheep were highly susceptible to the hemolysin, and those of pigs and guinea pigs were less susceptible, whereas RBC of 60-day-old chicks were not susceptible. The hemolysin was not inactivated by autoclaving at 121 C for 2 hours, and by treatments with formalin, trypsin, or pronase. The presence of calcium or magnesium ions did not change the activity, whereas iodoacetic acid significantly reduced the activity.
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PMID:Characterization of the hemolysin produced by haemophilus pleuropneumoniae. 683 24

A system was devised for studying the interaction of a trachoma strain of Chlamydia trachomatis (G17) and mouse fibroblasts (McCoy cells) in the absence of centrifugation, which is usually employed to enhance the infection of cell cultures with non-lymphogranuloma venereum human strains of C. trachomatis. In this system, the conditions of infection more closely approached those encountered in natural infections, and the entry of G17 into host cells could be compared with the previously described entry of C. psittaci 6BC and a lymphogranuloma venereum strain (440L) of C. trachomatis. McCoy cells were infected by shaking at 37 degrees C with inocula suspended in 0.01 M phosphate buffer, pH 7.2, containing 0.2 M sucrose. The efficiency of infection (inclusion counts without centrifugation/inclusion counts with centrifugation) was 1.5% for monolayers and 7.5% for suspensions. When measured either by inclusion counts or by host cell-associated 14C-amino acid-labeled G17, association was proportional to G17 concentration and increased linearly for 60 min. Pretreatment of host cells with diethylaminoethyl-dextran (30 micrograms/ml, 30 min) raised the efficiency of infection to about 13% for both monolayers and suspensions. Host cells treated with cytochalasin B (2 x 10(-5) M, 90 min) or trypsin (50 micrograms/ml, 60 min) associated with G17 at undiminished rates. 14C-labeled G17 inactivated by heat (60 degrees C, 3 min) or ultraviolet light (1,800 ergs per mm2) associated with McCoy cells at the same rate as live G17. Comparison of these results with those previously reported for strains 6BC and 440L showed that strain G17 exhibited some, but not all, of the host cell association properties of the other two chlamydial strains.
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PMID:Interaction between a trachoma strain of Chlamydia trachomatis and mouse fibroblasts (McCoy cells) in the absence of centrifugation. 721 62

A suction blister technique on the abdominal skin to separate pure human epidermis from its basement membrane is described. After incubation with proteolytic enzymes (trypsin, pepsin) and mechanical shaking, isolated cells and nuclei were stained with ethidium bromide. DNA-specific fluorescence was measured in a flow cytometer using UV excitation light. Cell-cycle phase distributions were obtained from the resulting histograms using a planimetric method. The proportion of cells with an S-phase DNA content showed circadian variations with peak values shortly before noon, and lower values during the rest of the 24 h period.
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PMID:Flow cytometry (FCM) of human epidermal cells. A preparation method for epidermal cells and demonstration of circadian variations in the proportion of S-phase cells. 745 5

1. Two types of nylon-6 supports (small cylinders and a sponge-like derivative) were prepared for immobilizing enzymes. Nylon-6 beads were solubilized by immersion in 80% formic acid and then reprecipitated using two different types of non-solvent solutions (distilled water or a 1:1 acetone:water solution) giving rise to a sponge-like derivative and to a colloidal suspension, respectively. The latter was molded into a thin thread which was cut into small cylinders. 2. Trypsin (EC 3.4.21.4) was covalently bound to glutaraldehyde-activated nylon-6 cylinders as well as to the sponge-like derivative. The maximum (100%) apparent initial enzymatic activity was found for the trypsin bound to small cylinders, while the initial activity of trypsin bound to the sponge-like material was 61% in comparison with that of trypsin-small cylinders, under the same conditions of enzyme immobilization reaction (1 g of nylon support and 5 ml of 1.3 mg/ml trypsin in 0.1 M sodium phosphate buffer, pH 8.5, at 10 degrees C for 18 h) and of enzymatic reaction (1 g of trypsin-nylon in a batch reactor, 2 ml of 0.7% w/v azocasein solution in 50 mM borate buffer, pH 8.5, at 37 degrees C, with shaking, for 1 h). However, the decrease of activity after enzyme immobilization was more conspicuous for the trypsin-small cylinders than for the trypsin-sponge. The former retained approximately 25% of its initial activity, while the latter retained approximately 67% of its initial activity, after seven cycles of utilization for 1 h, pH 8.5, at 37 degrees C and 8 days of storage, pH 8.5, at 4 degrees C in the presence of azocasein. 3. Scanning electron microscopy was performed to visualize the surface of the support after each step of the immobilization process. The electron micrographs show that the two types of nylon supports had a rough surface, which became rougher and full of craters after treatment with 5 N HCl. On the other hand, the partially hydrolyzed nylon surface acquired the appearance of Swiss cheese after treatment with 2.5% glutaraldehyde. After reaction with the enzyme molecules the surface became rougher again.
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PMID:Nylon-6 cylinders and a sponge-like derivative as supports for immobilizing trypsin. 787 18

Some clinical strains of Vibrio cholerae non-O1 produce an extracellular factor that evokes a rapid and dramatic cytotoxic response which manifests as cell rounding of Chinese hamster ovary (CHO) and HeLa cells without accompanying membrane damage. This study was performed to establish the identity of the non-membrane-damaging cytotoxin (NMDCY), which was not inhibited by antitoxins against cholera toxin, heat-labile toxin of enterotoxigenic Escherichia coli, El Tor hemolysin, Shiga-like toxin I, and Shiga-like toxin II, indicating that NMDCY did not bear an apparent immunological relationship with the above toxins and hemolysin. Brain heart infusion broth and AKI medium supported the maximal production of NMDCY; culture supernatant of AKI medium was found to be free of hemolysin activity, whereas in brain heart infusion broth hemolysin was coproduced with NMDCY. Maximal production of NMDCY in AKI medium was observed at 37 degrees C under shaking conditions with the pH of the medium adjusted to 8.5. NMDCY was purified to homogeneity by a three-step purification procedure which increased the specific activity of the cytotoxin by 1.7 X 10(5)-fold. The denatured molecular weight of the purified toxin was 35,000, and the cytotoxin was heat labile and sensitive to trypsin. Purification of the cytotoxin revealed an enterotoxic activity as reflected by its ability to accumulate fluid in the rabbit ileal loop. Both the cytotoxic and enterotoxic activities of NMDCY could be inhibited or neutralized by antiserum raised against purified cytotoxin but not by preimmune serum. Immunodiffusion test between purified NMDCY and antiserum gave a single well-defined precipitin band which showed reactions of complete identity, while, in an immunoblot assay, a well-defined single band was observed in the 35-kDa region. Our results indicate that the cytotoxic and enterotoxic activities expressed by NMDCY appear to contribute to the pathogenesis of the disease associated with V. cholerae non-O1 strains which produce this cytotoxin.
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PMID:Purification and characterization of an extracellular secretogenic non-membrane-damaging cytotoxin produced by clinical strains of Vibrio cholerae non-O1. 875 40

Cucurbita maxima trypsin inhibitor I (CMTI-I), a member of the squash-type protease inhibitor family, is composed of 29 amino acids and shows strong inhibition of trypsin by its compact structure. To study the structure-function relationship of this inhibitor using protein engineering methods, we constructed an expression system for CMTI-I as a fused protein with porcine adenylate kinase (ADK). A Met residue was introduced into the junction of ADK and CMTI-I to cleave the fusion protein with CNBr, whereas a Met at position 8 of authentic CMTI-I was replaced by Leu. Escherichia coli JM109 transformed with the constructed plasmid expressed the fused protein as an inclusion body. After cleavage of the expressed protein with CNBr, fully reduced species of CMTI-I were purified by reversed-phase HPLC and then oxidized with air by shaking. For efficient refolding of CMTI-I, we used 50 mM NH4HCO3 (pH 7.8) containing 0.1% PEG 6000 at higher protein concentration. Strong inhibitory activity toward trypsin was detected only in the first of three HPLC peaks. The inhibitor constant of CMTI-I thus obtained, in which Met8 was replaced by Leu, was 1.4 x 10(-10) M. The effect of replacement of Met with Leu at position 8 was shown to be small by comparison of the inhibitor constant of authentic CMTI-III bearing Lys at position 9 (8.9 x 10(-11) M) with that of its mutant bearing Leu at position 8 and Lys at position 9 (1.8 x 10(-10) M). To investigate the role of the well conserved hydrophobic residues of CMTI-I in its interaction with trypsin, CMTI-I mutants in which one or all of the four hydrophobic residues were replaced by Ala were prepared. The inhibitor constants of these mutants indicated that those with single replacements were 5-40 times less effective as trypsin inhibitors and that the quadruple mutant was approximately 450 times less effective, suggesting that the hydrophobic residues in CMTI-I contribute to its tight binding with trypsin. However, each mutant was not converted to a temporary inhibitor.
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PMID:Synthesis of a squash-type protease inhibitor by gene engineering and effects of replacements of conserved hydrophobic amino acid residues on its inhibitory activity. 901 Sep 39

A special class of hydrophobically modified polyelectrolytes was studied wherein poly(acrylic acid) (PAA) was conjugated with Pluronic F127 NF surfactant. The Pluronic-PAA copolymer solutions form gels at low concentrations when exposed to bodytemperature. Such gels possess enhanced retention in topical applications. Circular dichroism spectra indicate that tertiary structures of human insulin, haemoglobin, and albumin were stabilized in solutions of Pluronic-PAA. Aggregation of insulin in gelled solutions of Pluronic-PAA was impeded as demonstrated in shaking tests. The presence of Pluronic-PAA hindered the insulin degradation by alpha-chymotrypsin by at least 7-fold. Extraction of calcium ions from trypsin by Pluronic-PAA led to the dramatic changes in the tertiary structure and total loss of enzymatic activity, suggesting that Pluronic-PAA could inhibit tryptic degradation of proteins.
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PMID:Interactions among proteins and hydrophobically modified polyelectrolytes. 1134 72

A series of experiments on various factors which induce optimal in vitro excystation of the metacercariae of Metagonimus yokogawai isolated from the fish, Plecoglossus altivelis was conducted and the following results were obtained. 1)The metacercariae used in this experiment were isolated by the digestion technique therefore all of them were pretreated with the acid-pepsin solution before being applied to the various tests. 2)No excystation occurred when the metacercariae were placed in a salt solutions such as physiological saline, Tyrode solution and Veronal, Tris buffers alone or in combination. 3)The metacercariae underwent complete excystation in the trypsin and pancreatin solution in Tris buffer within an hour at 38 degrees C. The best results were obtained in 0.8-0.9% trypsin solutions, pH 8.0-8.6 and at 38-40 degrees C, approximately one hundred per cent excystation occurred in 40 minutes. Not only temperature but also hydrogen ion concentration played an important role causing excystation of the metacercariae in trypsin-Tris buffer solution. However, bile salts were not responsible for the excystation. 4)Agitation effect on the excystation was tested as a mechanical stimulus and it was found that the shaking stimulus accelerated the excysting mechanism, compared with the metacercariae on which it was not imposed. It is concluded that the metacercariae pretreated in the acid pepsin solution demonstrates an essential requirement for the enzyme solution such as trypsin or pancreatin, provided with the optimum conditions of temperature and hydrogen ion concentration in excysting medium.
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PMID:Study On Metagonimus Yokogawai (Katsurada, 1912) In Korea: II. The In Vitro Excystation Of Metacercariae. 1291 12

Purified lipase, injected intracerebrally and intravasculariy in rabbits, gave rise to focal areas of demyelinization in the central nervous system in 10 of 13 animals so treated. In one instance the lesions became manifest within 48 hours and in another they persisted for 6 months; they were not infrequently accompanied by paresis and by tilting or tremor of the head. They were characterized by a focal loss of myelin and moderate gliosis with little or no neuronal destruction or inflammatory reaction, in these respects resembling the plaques of multiple sclerosis. The intracerebral injection of trypsin and chymotrypsin in control animals failed to produce the characteristic demyelinization, but by contrast caused focal areas of necrosis in which all the cerebral tissues were involved. Furthermore, demyelinization did not result when heat-inactivated pancreatic lipase was injected intracerebrally, and similarly negative results were obtained when an incubated mixture comprised of fatty connective tissue that had been acted upon by the pancreatic preparation and then heated to inactivate the lipase, was injected into the brains of rabbits. In supplementary experiments the pancreatic lipase preparation and fresh rabbit brain, incubated together in vitro, were found to form acid, presumably owing to the breakdown of brain lipids to fatty acids; trypsin and chymotrypsin mixed with brain in control experiments failed to form acid. When incubated with segments of the spinal cord of experimental animals, the lipolytic enzyme brought about a loss of stainable myelin in peripheral areas and in the spinal nerve roots; again trypsin and chymotrypsin had no such effect in control experiments. The findings as a whole show that an enzyme preparation with lipolytic activity has the ability to destroy myelin in living animals, and in vitro as well, and to produce lesions remarkably similar to those of multiple sclerosis. They have additional interest in light of the demonstration that a lipolytic enzyme is regularly present in the reactive histiocytes of guinea pigs with experimental encephalomyelitis (5).
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PMID:Demyelinization induced in living rabbits by means of a lipolytic enzyme preparation. 1482 2


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