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At least 19 recordsLinked to original sources
PubMed2026

Interactive gaming during inhalational induction of anesthesia reduces pediatric patient anxiety and improves induction compliance: A randomized controlled trial.

BACKGROUND: Preoperative anxiety affects up to 75% of pediatric surgical patients and is associated with adverse postoperative outcomes. Traditional anxiolytic strategies with premedication carry drawbacks including delayed recovery and paradoxical reactions, driving interest in non-pharmacologic alternatives. Audiovisual distraction represents one approach, encompassing passive methods (e.g. watching a video) and active modalities (e.g. interactive gaming). The Bedside Entertainment and Relaxation Theater (BERT) is a projection-based environment that enables audiovisual distraction during induction. Whether BERT-based interactive gaming reduces anxiety and improves induction compliance compared to standard perioperative care remains unknown. METHODS: This single-center RCT enrolled 74 pediatric patients aged 4 to 14 undergoing inhalational induction, randomized to standard care (SOC) or interactive gaming via BERT added to SOC during induction (BERT). The primary outcome was change in patient anxiety from baseline to induction, measured using the Modified Yale Preoperative Anxiety Scale (mYPAS). Secondary outcomes included caregiver anxiety, induction compliance, OR efficiency, opioid administration, and OR staff perceptions. RESULTS: Patients in the BERT group experienced significantly smaller increases in anxiety from baseline to induction than SOC (median mYPAS increase [IQR]: 0 [0 to 0] vs 10 [0 to 38], p&#xa0;<&#xa0;0.001). Induction compliance improved, with lower Induction Compliance Checklist (ICC) scores indicating fewer induction-related disruptive behaviors than SOC (median: 0 vs 1, shift -1 [95% CI: -2 to 0]; p&#xa0;=&#xa0;0.004). Caregiver anxiety increased less in the BERT group than SOC (mean STAI increase: 0.18 vs 1.89, difference&#xa0;-&#xa0;1.7, [95% CI: -3.2 to -0.26]; p&#xa0;=&#xa0;0.022). OR staff reported high acceptability, with 97% supporting continued use. No differences were observed in OR efficiency or opioid administration between groups. CONCLUSIONS: Interactive gaming via BERT attenuated increases in patient anxiety, improved induction compliance, and reduced the rise in caregiver anxiety without prolonging OR time. These findings support BERT as an effective, workflow-compatible anxiolytic strategy for pediatric inhalational induction.

Humans↗
PubMed1979

Steroid induction of delta-aminolevulinic acid synthase and porphyrins in liver. Structure-activity studies and the permissive effects of hormones on the induction process.

Quantitative aspects and structure-activity relationships of the inducing effects of natural steroids on delta-aminolevulinic acid (ALA) synthase and porphyrins have been investigated in monolayer cultures of chick embryo liver cells maintained in a serum-free medium as well as in the chick embryo liver in ovo. Many 5 alpha and 5 beta metabolites of neutral C-19 and C-21 hormones and hormone precursors stimulated porphyrin formation and ALA-synthase induction in the cultured liver cells as we have previously described. In these inducing actions a number of 5 beta epimers (A:B cis) were found to be more potent than their corresponding 5 alpha epimers (A:B trans). The structure-activity relationship between 5 beta and 5 alpha steroid epimers with respect to ALA-synthase induction in culture was also found to prevail with respect to induction of this enzyme in chick embryo liver in ovo. Hemin in concentrations of 2 x 10(-7) M inhibited steroid induction of porphyrin formation, and CaMgEDTA enhanced the responsiveness of the cultured liver cells to steroids by approximately 10 times. The addition of insulin, or insulin plus hydrocortisone or insulin plus hydrocortisone plus triiodothyronine, was important for the maintenance of protein synthesis and essential for maximal expression of the ability of steroids to induce porphyrins and ALA-synthase in the "permissive" effect which insulin, hydrocortisone, and triiodothyronine exert on allylisopropylacetamide induction of porphyrins and ALA-synthase also extends to the induction process which is elicited by natural steroids. These findings also strongly suggest that the regulation of hepatic porphyrin-heme biosynthesis by endogenous as well as exogenous chemicals is significantly influenced by the internal hormonal milieu.

5-Aminolevulinate Synthetase↗
PubMed1977

Genetic regulation of UDP-glucuronosyltransferase induction by polycyclic aromatic compounds in mice. Co-segregation with aryl hydrocarbon (benzo(alpha)pyrene) hydroxylase induction.

Induction of hepatic 4-methylumbelliferone UDP-glucuronosyltransferase (EC 2.4.1.17) by polycyclic aromatic compounds, such as 3-methylcholanthrene or beta-naphthoflavone, occurs in C57BL/6N, A/J, PL/J, C3HeB/FeJ, and BALB/cJ but not in DBA/2N, AU/SsJ, AKR/J, or RF/J inbred strains of mice. This pattern of five responsive and five nonresponsive mouse strains parallels that of the Ah locus, which controls the induction of aryl hydrocarbon (benzo[alpha]pyrene) hydroxylase (EC 1.14.14.2). Induction of the transferase is maximal in C57BL/6N mice with 200 mg of 3-methylcholanthrene/kg body weight; no induction occurs in nonresponsive DBA/2N mice even at a dose of 400 mg/kg. The rise of inducible transferase activity lags 1 or more days behind the rise of inducible hydroxylase activity and peaks 5 days after a single dose of 3-methylcholanthrene. In offspring from the appropriate backcrosses and intercross between C57BL/6N and DBA/2N parent strains, the genetic expression of 3-methylcholanthrene-inducible transferase activity is inherited as an additive (co-dominant) trait. This expression differs distinctly from that of the inducible hydroxylase activity, which is inherited almost exclusively as a single autosomal dominant trait in these same animals. The more potent inducer 2,3,7,8-tetrachlorodibenzo-p-dioxin induces the transferase more than 3-fold in C57BL/6N mice and less than 2-fold in DBA/2N mice, whereas the hydroxylase is induced equally (about 8-fold) in both strains. A dose of 3-methylcholanthrene given 3 days after 2,3,7,8-tetrachlorodibenzo-p-dioxin, at a time when hydroxylase induction in both strains is very high, does not enhance the rise in inducible transferase activity seen in C57BL/6N or DBA/2N mice which have received 2,3,7,8-tetrachlorodibenzo-p-dioxin alone. These data indicate that (a) the inducibility of two metabolically coordinated membrane-bound enzyme activities may be regulated by a single genetic locus, and (b) although the hydroxylase can be fully induced in the nonresponsive DBA/2N strain by 2,3,7,8-tetrachlorodibenzo-p-dioxin prior to 3-methylcholanthrene treatment, metabolites of the 3-methylcholanthrene treatment, metabolites of the 3-methylcholanthrene treatment, metabolites of the 3-methylcholanthrene, presumably present in the liver, are incapable of inducing further the transferase activity. The difference in sensitivity between 3-methylcholanthrene and the more potent inducer 2,3,7,8-tetrachlorodibenzo-p-dioxin for both the hydroxylase and the transferase activities suggests the possibility of a common receptor in regulating both enzyme induction processes.

Age Factors↗
PubMed1976

Activation of 3':5'-cyclic AMP-dependent protein kinase and induction of ornithine decarboxylase as early events in induction of mixed-function oxygenases.

The parenteral administration of a single dose of 3-methylcholanthrene to rats caused an increase in the liver of the concentration of 3', 5'-cAMP and of the activity of cAMP-dependent protein kinase (ATP:protein phosphotransferase, EC 2.7.1.37). These events were followed by an increased activity of ornithine decarboxylase (L-ornithine carboxy-lase, EC 4.1.1.17), the enzyme that controls the biosynthesis of polyamines. Finally, the activity of benzo[a]pyrene hydroxylase, as well as the amount of cytochrome P-448, was increased. Similarly, after the administration of phenobarbital, there was first an increase in the cAMP concentration and in the activity of cAMP-dependent protein kinase, then the induction of ornithine decarboxylase, and finally, an enhanced activity of ethylmorphine N-demethylase and an increased content of cytochrome P-450. These data suggest that the drug-induced processes in liver that increase the activities of the oxidative, and presumably other, drug-metabolizing enzymes include the following sequence of events: (1) increase in cAMP concentration and/or activation of cAMP-dependent protein kinase; (2) induction of ornithine decarboxylase; and, (3) induction of drug-metabolizing enzymes.

Animals↗
PubMed1978

Studies on induction and control of cell-mediated autoimmunity. II. Prevention of induction and activity of autoreactive T cells by suppressor cells and by a suppressive serum factor.

Autoreactive T lymphocytes (T-ARC) can be detected in the spleen of mice treated with a single dose of cyclophosphamide (CY) (125 mg/kg), a peak occurring 6 days after CY injection. Eight days after CY treatment, the mice develop a specific anergic state. This anergic state can be transferred to normal syngeneic animals by either splenic nylon wool-nonadherent lymphocytes (suppressor cells, S-ARC) or by the serum of anergic mice, implying the development of an active suppressive mechanism due to CY treatment. Precursors of both potentially T-ARC as well as S-ARC coexist in the spleen of normal animals. Precursors of S-ARC present in the spleen and in the thymus of normal animals are sensitive to CY. However, committed S-ARC obtained from anergic mice are resistant to CY. Committed S-ARC as well as their precursors prevent induction of T-ARC. Committed S-ARC counteract expression of committed T-ARC activity, whereas precursors of S-ARC fail to do so. The autoimmune phenomenon described here represents an in vivo animal model system for induction of T-ARC and for the control mechanism which normally prevents induction and/or expression of cell-mediated autoreactivity by specific suppressor cells and by suppressive factors.

Animals↗
PubMed1975

[Enzyme induction in Streptomyces hydrogenans. V. Characterization of testosterone-17 beta-dehydrogenase and its induction by steroids].

Testosterone 17beta-dehydrogenase can be enriched from Streptomyces hydrogenans. The enzyme dehydrogenizes testosterone with Km=13muM and estradiol-17beta with Km=21muM to the corresponding 17-ketoderivatives. NAD forms NADH with Km=125muM. The enzyme is strongly inhibited by androstandione and 17alpha-methyltestosterone. The Ki for 17alpha-methyltestosterone is 18muM. The enzyme activity increases with increasing pH up to alkali-mediated denaturation at about pH 10. The optimum temperature is at 45 degrees C. If Streptomyces hydrogenans is cultivated in the absence of steroids, the specific activity of testosterone 17beta-dehydrogenase in the cytosol of the microorganisms amounts to 10 mU/mg protein, and increases up to 10-fold if the cells are cultivated in the presence of certain steroids. Testosterone, alpha-dihydrotestosterone, beta-dihydrotestosterone, estradiol-17beta, and 17alpha-methyltestosterone are very effective inducers. Thus, for the first time, the ability of estradiol-17beta to induce an enzyme synthesis in a microorganism is shown. The steroid-dependent induction is inhibited by testosterone acetate and rifamycin SV. Cyproterone, however, does not decrease the testosterone-dependent enzyme induction of testosterone 17beta-dehydrogenase.

Androstane-3,17-diol↗
PubMed1977

Induction of aminolevulinate synthase and porphyrins in cultured liver cells maintained in chemically defined medium. Permissive effects of hormones on induction process.

Primary liver cells, isolated from 16- 17-day-old chick embryos, were incubated in a serum-free chemically defined medium (Ham's F12) supplemented with hormones for up to 6 days. The culture method also includes the complete removal of contaminating red cells before the initiation of culture. On the 2nd day in cluture, the level of amino-levulinate (ALA) synthase activity in response to allylisopropylacetamide (AIA) was increased 6-fold in cells grown in F12. Insulin, hydrocortisone, and triiodothyronine alone had no appreciable effects on ALA synthase levels. On the other hand, when added with AIA, insulin, insulin plus hydrocortisone, insulin plus hydrocortisone triiodothyronine increased ALA synthase levels 17-, 50-, 110-fold, respectively. The maximally induced levels of ALA synthase activity by AIA in the presence of insulin, hydrocortisone, and triiodothyronine were approximately 15 nmol of ALA/mg of protein/h, 37 degrees or 3 micronmol of ALA/g of tissue/h, 37 degrees, a value similar to that found in ovo or at least 5 times greater than that found in rat liver. The morphology of hepatocytes was maintained for at least 6 days in culture, although the induction of ALA synthase was reduced after the 4th day unless triiodothyronine was present. Dibutyryl adenosine 3':5'-monophosphate (10(8) M) or glucagon (5x10(8) M) had little effect on the induced as well as noninduced levels of ALA synthase or porphyrins. These data demonstrate a "permissive" effect of insulin, hydrocortisone, and triiodothyronine on the induction of ALA synthase and porphyrins by AIA in cultured chick embryo liver cells. In the absence of insulin hydrocortisone, or triiodothyronine, AIA produces only a slight increase in ALA synthase activity or porphyrins (or both); on the other hand, it produces a marked increase in the enzyme activity and porphyrins when these hormones are added to the culture medium. The term "permissive" is applied to these hormone-dependent effects. A sensitive spectrofluorometric method for heme quantitation allowed us to follow changes in the cellular heme content in hemoglobin-free cultured liver cells. Heme content in the cultured liver cells was approximately 250 pmol/mg of protein at the initiation of culture but gradually declined to 175 pmol/mg of protein at the initiation of culture but gradually declined to 175 pmol/mg of protein during 48 h of incubation. The apparent decrease in heme content may be accounted for by the concomitant increase in protein content in these cells.

5-Aminolevulinate Synthetase↗
PubMed1975

Tolerance induction in B lymphocytes but thymus-dependent antigens. T cells may abrogate B-cell tolerance induction by prevent an antibody response.

Thymus-dependent protein antigens such as fowl gamma globulin (FGG) and dinitrophenylated-human gamma globulin (DNP-HGG), readily induced tolerance of the B cell in the absence of T cells even when these antigens were not deaggregated. However, when the same doses of antigen were given in the presence of T cells, the B-cell population was shown to be protected from tolerance induction, especially when the antigen was not in a deaggregated form. In this case, there was in fact evidence of a priming effect, manifest in both the B-cell and T-cell populations. The priming effect on the B-cell population was demonstrated by an increased response of mice pretreated with DNP-HGG, upon challenge with DNP conjugated to a heterologous carrier. The priming effect on the T-cell population was evident in a helper effect demonstrated in vitro. However, when euthymic mice which had been pretreated with large doses of FGG or DNP-HGG were challenged with the homologous carrier, the results were different. In this case, there was a profound suppression of the response against the carrier or the hapten on that carrier. Suppressor activity was also demonstrated in vitro and was shown to be sensitive to treatment with anti-theta-serum plus complement. Additionally it was shown that the effector phase of the suppression had a definite nonantigen-specific component. Thus, in pretreated euthymic mice, provided the homologous carrier was present, the response to a heterologous carrier was also suppressed. To account for the observation that nondeaggregated antigens can induce B-cell tolerance in athymic mice, but B-cell priming and T-cell-mediated suppression in euthymic mice, it is proposed that B-cell tolerance occurs when antigen at some critical dose interacts with the B cell in the absence of some second signal. This second signal is normally provided by the macrophage, probably with the assistance of the T cell, and its effect is to divert the result of the interaction of the B cell with antigen towards immunization and away from tolerance induction. When a large dose of an antigen that tends to form aggregates is given to an animal possessing functional T cells, both T-dependent helper and T-dependent suppressor activities are generated, thus accounting for a situation where the B-cell population is immunized, but B-cell activation is suppressed in the presence of the original carrier.

Animals↗
PubMed1977

[Attempts at biotechnical induction of puberty in young female pigs. 2. Effects of various time intervals between one puberty induction with PMS and HCG to the following estrus synchronization on estrus and ovulation in animals about 190 days old].

A biological engineering approach to induce puberty in 125 young female fattening pigs aged 190 days was undertaken on the basis of a mixture of 500 IU PMS (Prolosanserum, Dessau) with 250 IU HCG (Gonabion, Dresden). The injections were made subcutaneously. Pronounced oestrus symptoms were recorded from the external genital organs of 80% of the probands up to ten days after injection, associated with toleration in 52.8% of them. Toleration usually started on the fourth to sixth days after injection. Cycles began to develop in 57.1% up to the next oestrus period. Animals with -/x weight increase per die of 400 g exhibited lower responses. Results in terms of heat and ovulation were lower along with shorter intervals, when oestric synchronisation was undertaken 53, 32, and 17 days after the induction of puberty (20 days Suisynchron, Bernburg; 750 IU PMS).

Animals↗
PubMed1976

Suppressor cell induction in vitro. I. Kinetics of induction of antigen-specific suppressor cells.

The induction of antigen-specific suppressor cells in vitro, using high concentrations (100 mug/ml) of keyhole limpet hemocyanin (KLH) in Marbrook flasks is described. Spleen and cortisone-resistant thymocytes were the richest source of suppressor cell precursors, compared to lymph node cells, peripheral blood lymphocytes or thoracic duct lymphocytes. Suppressor cells induced with KLH only suppressed KLH-reactive helper cells, and not B cells or helper cells of other specificity. The suppressor cells were T cells, as judged by their sensitivity to anti-Thy-1.2, heterologous anti-T, but not anti-B antisera.

Animals↗
PubMed1979

In vitro induction of cytotoxic effector cells against human neoplasms. I. Sensitization conditions and effect of cryopreservation on the induction and expression of cytotoxic responses to allogeneic leukemia cells.

Peripheral blood lymphocytes (PBL) from normal human donors were sensitized in vitro against allogeneic human acute myelocytic leukemia (AML) cells by means of an unidirectional mixed lymphocyte-tumor cell culture (MLTC) technique. The cytotoxic responsiveness of the sensitized lymphocytes, as determined in vitro by the 51Cr-release assay, varied among individual lymphocyte donors and was greatly dependent on the sensitization culture conditions. Induction of cytotoxic effector cells was augmented appreciably by adding to the cultures minute amounts of the immunopotentiating agent MER-BCG. Responding lymphocytes and stimulating leukemia cells cryopreserved for several weeks in liquid nitrogen were as effective as fresh cells in generating effector lymphocytes; the cytotoxic capacity of already sensitized lymphocytes was fully retained by cryopreservation. The implications of these findings for possible clinical employment of in vitro sensitized lymphocytes in adoptive immunotherapy of cancer are discussed.

Adult↗
PubMed1977

Elective induction of labor conducted under lumbar epidural block. I. Labor induction by amniotomy and intravenous oxytocin.

Epidural analgesia (bupivacaine) was administered during labor after amniotomy, in some cases supplemented by intravenous oxytocin. A higher incidence of transient uterine hypertonus was seen after blocking. Fetal heart rate changes mainly took the form of bradycardia (in association with uterine hypertonus). At birth, the maternal biochemical condition was characterized by a lower degree of metabolic acidosis, compared to normal unanesthetized controls. The fetuses displayed a slight degree of hypoxia and hypercapnia. The mechanisms underlying these modifications are discussed. Epidural blockade in combination with elective induction of labor, whether or not supplemented by intravenous oxytocin, may carry a risk. Its magnitude is considered acceptable for both mother and fetus provided they are constantly under close surveillance, limited amounts of bupivacaine are administered and the second stage of labor is kept short. However, some warnings against epidural analgesia apply to patients with placental insufficiency and very active labor.

Adult↗
PubMed1976

[Induction of endogenous C-type virus by 5-iododeoxyuridine and augmentation of this induction by polycyclic hydrocarbons].

When the MLg Mouse cells were treated with the chemical carcinogens, in the presence of microsomal enzymes and NADPH2 after 5-iododeoxyuridine (IUdR) treatment, the induction frequency of the endogenous C-type virus was increased by nearly 10-fold in comparison with the cultures treated with IUdR only. In the preliminary screening of several polycyclic hydrocarbons including carcinogenic and non-carcinogenic products, apparently there was no correlation between the carcinogenecity in vivo and the stimulation capacity of IUdR induced C-type virus activation in our test conditions.

Cells, Cultured↗
PubMed1977

Mechanism for induction of anti-DNA antibodies by bacterial lipopolysaccharides in mice; II. Correlation between anti-DNA induction and polyclonal antibody formation by various polyclonal B lymphocyte activators.

The capacity of various polyclonal B lymphocyte activators (PBA) to induce, in mice, the formation of anti-DNA antibodies was compared with their ability to mediate the release of DNA in circulating blood and to stimulate polyclonal antibody synthesis in vivo. Anti-DNA antibodies or polyclonal antibody synthesis were induced in mice after the injection of at least 10 microgram lipopolysaccaride (LPS) from Salmonella typhimurium, 1 mg dextran sulfate (DS), or 2 mg purified protein derivative of tubercle bacteria RT32 (PPD). Smaller quantities of LPS (0.1 microgram) or DS (500 microgram) were sufficient to cause the release of DNA in circulating blood, whereas PPD was not able to provoke such a release at any concentration used. The association of anti-DNA antibodies with polyclonal antibody synthesis in mice injected with various PBA contrasts with the lack of correlation between the formation of anti-DNA antibodies and the release of measurable amounts of DNA in circulating blood. These results strongly suggest that the induction of anti-DNA antibodies by PBA is a consequence of the polyclonal B lymphocyte activation.

Animals↗
PubMed1978

Liver mixed function oxidases in chickens: induction by polychlorinated biphenyls and lack of induction by DDT.

Microsomal hydroxylase and demethylase activities were compared in livers from White Leghorn cockerels fed polychlorinated biphenyls (PCBs) containing 21 to 68% chlorine, or p,p'-DDT. The higher chlorinated PCBs, Aroclor 1254 and 1268, were potent inducers of hepatic enzyme activity while DDT did not induce these enzymes. Aroclor 1254 was the most potent inducer because feeding 5 ppm increased liver aminopyrine demethylase activity 1.5X but did not affect liver weight. Feeding 50 and 500 ppm of Aroclor 1254 and 1268 increased liver weight and demethylase activity per mg of protein. A differential response in the two enzymes occurred. Only 500 ppm of Aroclor 1268 increased hydroxylase activity. Aroclor 1242 had no effect on liver enzyme concentration but 50 and 500 ppm of Aroclor 1242 increased liver weights and consequently increased total enzyme activity. Our data demonstrated that in the avian species DDT and PCB did not have the same effect on hepatic microsomal enzyme activity.

Aniline Hydroxylase↗