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PubMed1999

Assessment of extensive surgery for locally advanced lung cancer. Safety and efficacy of induction therapy.

OBJECTIVE: Locally advanced lung cancer has a poor prognosis, despite extensive surgery conducted in an effort to improve survival. We evaluated the safety and efficacy of induction therapy prior to extensive surgery for locally advanced lung cancer. METHODS: Primary resection for lung cancer was done in 549 consecutive patients divided into three groups; 446 undergoing standard pulmonary resection (no extensive surgery), 87 undergoing extensive surgery without induction therapy, and 16 undergoing surgery after induction therapy. RESULTS: Morbidity was 23.5%, 28.6%, and 43.8%, respectively. The rate was significantly higher in the induction group compared with the no extensive surgery group (P < 0.05). Surgical mortality was 0.67%, 3.4%, and 6.3%, respectively. The difference was statistically significant between the no extensive surgery and extensive surgery groups (P < 0.02), and between the no extensive surgery and induction groups (P < 0.02). Hospital mortality was 2.2%, 9.2%, and 6.3%, respectively. The rates were significantly higher in the extensive surgery (P < 0.01) and induction (P < 0.05) groups compared to the no extensive surgery group. Five-year survival was 50.3% for the patients who received induction therapy, and 14.7% for the patients who did not receive induction therapy. CONCLUSIONS: Survival differences between the induction and non induction groups were not significant, but some patients with T3 or T4 disease may benefit from induction therapy. The high morbidity of induction treatment should be recognized, and strict candidate selection and careful postoperative care used to help prevent increased mortality.

Adenocarcinoma↗
PubMed1987

Induction of metallothionein by steroids in rat primary hepatocyte cultures.

The purpose of this study was to characterize the induction of metallothionein (MT) by steroids in rat primary hepatocyte cultures. Comparison of the characteristics of MT induction by a steroid (dexamethasone) to that by metals (Zn and Cd), examination of the involvement of the glucocorticoid receptor in the steroid induction of MT, and determination of the potency and effectiveness of a number of steroids were studied. In general, the patterns of MT induction by metals and steroids were quite different. For metals, the maximal MT induction (12- to 39-fold) was limited by toxicity whereas for steroids, a plateau in MT induction (fivefold) occurred at noncytotoxic concentrations. Steroids elicited an increase in MT at concentrations that were one-hundredth to one-thousandth less than that of metals. A combination of metal and steroid increased the induction of MT to a level higher than achieved by metal or steroid alone. The effectiveness of steroids at inducing MT was related to their ability to induce a specific glucocorticoid effect, induction of tyrosine aminotransferase. For specific classes of steroids, synthetic glucocorticoids were more potent than the metals in inducing MT, but endogenous glucocorticoids, mineralocorticoids, androgens, and estrogens were less potent than the metals. The concentration of corticosterone, the major endogenous glucocorticoid of rats, required to induce MT in hepatocytes was 100 times higher than concentrations achievable in the plasma of rats. In conclusion, in rat hepatocytes dexamethasone was a more potent but less effective inducer of MT than Zn or Cd; synthetic glucocorticoids were more potent but endogenous adrenalcorticoids (i.e., glucocorticoids, mineralocorticoids, androgens, and estrogens) were both less potent and less effective inducers of MT than were metals, suggesting that glucocorticoids may not be the mediator for stress-induced MT induction; and induction of MT by steroids correlated well with the induction of tyrosine aminotransferase, supporting the involvement of a hormone-receptor complex in the induction of MT by steroids.

Animals↗
PubMed2005

Low morbidity and mortality for bronchoplastic procedures with and without induction therapy.

BACKGROUND: The safety of bronchoplastic procedures after induction chemoradiotherapy is uncertain. This study examines short- and long-term outcomes after bronchoplastic procedures with and without induction therapy. METHODS: Between January 1997 and September 2004, more than 1,300 anatomic pulmonary resections for cancer were performed at a single institution. Of these, 73 patients required either sleeve lobectomy (57) or bronchoplasty (16), and were retrospectively analyzed. Nineteen patients (26%) received induction therapy; 15 received chemotherapy and radiation therapy and 4 received chemotherapy alone. Fifty-four patients underwent the bronchoplastic procedure without induction therapy. Mortality and early and late morbidity were analyzed. RESULTS: Mean follow-up was 25 months. Histology was nonsmall cell cancer in 62 (85%), carcinoid in 8 (11%), and renal cell cancer, schwannoma, and mucoepidermoid cancer in 1 patient each. There were 2 (2.7%) 30-day deaths, both in the group not receiving induction therapy. Of the surviving 71 patients, 70 had functional reconstructions at last follow-up. The overall 30-day complication rate was 30% (19 of 54) in patients not receiving induction therapy (no bronchopleural fistulas) and 42% (8 of 19) occurring in those receiving induction therapy (1 bronchopleural fistula). The long-term complication rate was 20% (11 of 54) among patients not receiving induction therapy and 5% (1 of 19) among those receiving induction therapy (completion pneumonectomy). There were no bronchovascular complications. Interventional bronchoscopy was required in 7 patients not receiving induction therapy, and was required in none of the patients receiving induction therapy. CONCLUSIONS: Anatomic pulmonary resections utilizing bronchoplastic techniques can be performed with low morbidity and mortality rates even after induction therapy.

Adolescent↗
PubMed2005

Coincident stimulation of convergent cortical inputs enhances immediate early gene induction in the striatum.

The effect of coincident stimulation of convergent corticostriatal inputs was analyzed by the induction of immediate early genes in striatal neurons. Cortical motor areas were stimulated through implanted electrodes in awake, behaving rats, and the induction of the mRNAs encoding the immediate early genes (IEGs) c-fos and arc was analyzed in the striatum with in situ hybridization histochemistry. In the first experiment, unilateral stimulation of the medial agranular cortex, orofacial region of the lateral agranular cortex or the forelimb region of the lateral agranular cortex resulted in IEG induction in the striatum, which was restricted to the topographically related area receiving input from the stimulated cortical area. In a second experiment, stimulation parameters were altered, including frequency, number of pulses/train, and number of trains/s. These parameters did not have a significant effect on IEG induction. Notably, in some cases, in which there was IEG induction not only in the stimulated cortical region, but also in the homologous area in the contralateral hemisphere, very robust IEG induction was observed in the striatum. In a third experiment, the orofacial regions of the lateral agranular cortex of both hemispheres were stimulated coincidently. All of these animals showed robust striatal IEG induction. This IEG induction was attenuated by pretreatment with an NMDA antagonist MK-801. In a fourth experiment, we tested whether the coincidence of bilateral cortical stimulation contributed to the efficacy of striatal IEG induction. Either alternating stimulation or coincident stimulation of non-homologous cortical regions produced significantly lower striatal IEG induction than obtained with coincident stimulation of homologous cortical areas. Enhanced striatal IEG induction occurred in indirect striatal neurons, labeled with enkephalin, but was also present in a large number of enkephalin-negative neurons, most of which are likely direct pathway neurons. These results suggest that regional and temporal convergence of cortical inputs enhances striatal IEG induction.

AIDS-Related Complex↗
PubMed1998

Severe preeclampsia remote from term: labor induction or elective cesarean delivery?

OBJECTIVES: The study's objectives were as follows: (1) to determine the rate of vaginal delivery after labor induction in severe preeclampsia remote from term and (2) to determine potential predictors of success. STUDY DESIGN: Retrospective chart review was conducted on live-born singleton pregnancies complicated by severe preeclampsia and delivered at 24 to 34 weeks' gestation from January 1, 1992, to December 31, 1996. Exclusion criteria included eclampsia, presence of labor or spontaneous rupture of membranes on admission, and complication of pregnancy by an ultrasonographically detected fetal congenital anomaly. Patients were divided into 3 groups: elective cesarean delivery without labor, cesarean delivery after labor induction, and vaginal delivery after labor induction. Statistical analyses included multiple logistic regression, the Student t test, the chi2 test, and the Mann-Whitney test. P </=.05 was considered significant. RESULTS: A total of 306 charts were reviewed. Among these, 161 patients (52.6%) underwent elective cesarean delivery without labor; the 2 most common indications were unfavorable cervix (33.5%) and malpresentation (22.4%). The remaining 145 patients (47.4%) underwent labor induction with a 48. 3% rate of vaginal delivery after induction, ranging from 31.6% at </=28 weeks' gestation to 62.5% at >32 weeks' gestation. The most common indication for cesarean delivery after induction, in 50.7% of the cases, was nonreassuring fetal heart rate. The median Bishop score was significantly higher (3 vs 2, P =.004) and the total hospital stay was significantly shorter in the vaginal delivery after induction group than in the cesarean delivery after induction group. However, there were no significant differences between the 2 groups in use of cervical ripening agents, gestational age at delivery, birth weight, 5-minute Apgar score, or postpartum endometritis. After exclusion of cesarean deliveries performed for malpresentation, there was no statistically significant difference in classic incision rates between the elective cesarean delivery without labor and cesarean delivery after induction groups (13.6% vs 6.8%; P =.137). According to logistic regression analysis, only the Bishop score was significantly associated with a successful induction (odds ratio 1.38, 95% confidence interval 1.11-1.71). Gestational age reached marginal significance (odds ratio 1.30, 95% confidence interval 0.89-1.89). CONCLUSIONS: (1) Labor induction should be considered a reasonable option for patients with severe preeclampsia at </=34 weeks' gestation because 48% of patients given the chance were successfully delivered vaginally. (2) The Bishop score on admission is the best predictor of success, although the chance of successful labor induction increases with advancing gestational age.

Adult↗
PubMed1996

Tetracycline analogs affecting binding to Tn10-Encoded Tet repressor trigger the same mechanism of induction.

We examined the influence of substituents in tetracycline (tc) analogs modified at positions 2 and 4-9 and anhydrotetracycline (atc) on induction of the Tn10-encoded Tet repressor (TetR) by a quantitative in vitro induction assay. The equilibrium association constants of the modified tc to TetR were independently determined to distinguish effects on binding from those on induction. We found a correlation between the binding affinity and induction of TetR for most tc analogs. While a substitution at position 5 revealed only minor effects, changes at position 6 increased binding and induction efficiencies up to 20-fold. A chlorine at position 7 or 8 enhanced binding and induction about 4- and 9-fold, respectively. Substituents at position 9 decreased binding up to 5-fold. Epimerization of the dimethylamino function at position 4 in 4-epi-tc resulted in about 300-fold-reduced binding and 80-fold-reduced induction. Substitution of this grouping by hydrogen in 4-de(dimethylamino)-tc resulted in no binding and no induction. The respective atc analog failed to induce as well, although binding was still observed. The dimethylamino function may, thus, play a role in triggering the conformational change of TetR necessary for induction. Substitution of the 2-carboxamido by a nitrilo function did not influence binding and induction efficiencies. Atc showed about 30-fold increased binding and induction, being the most effective inducer tested in this study. The equilibrium association constants of most TetR-[Mg-tc]+ and TetR-([Mg-tc]+)2 analog complexes with tet operator are decreased about 10(2)- and 10(8)-fold, respectively, as compared to those of free TetR. This suggests that these tc analogs share the same molecular mechanism of TetR induction.

Bacterial Proteins↗
PubMed2001

Labor induction for the preterm severe pre-eclamptic patient: is it worth the effort?

OBJECTIVE: The purpose of this study was to examine the success rate of labor induction in patients with severe pre-eclampsia delivered at < or = 34 weeks' gestation; to identify factors associated with its success; and to evaluate neonatal outcomes based on induction success or failure. METHODS: We identified pregnancies complicated by severe pre-eclampsia delivered at < or = 34 weeks' at our institution from 1991 to 1998. Women who underwent labor induction and had successful vaginal delivery were compared to those who underwent labor induction, but required Cesarean delivery. Multiple logistic regression analyses were performed to assess factors associated with successful induction and neonatal outcome. RESULTS: Over the 7-year study period, there were 215 patients meeting the criteria. Sixty-four (29.8%) did not undergo a labor attempt; 69 of 151 (46%) women who underwent labor induction achieved vaginal delivery. Labor induction was successful in 0%, 6.6%, 35.3% and 68.5% of cases at 24-26, 27-28, 29-31 and 32-34 weeks' gestation, respectively. By logistic regression the only factor positively associated with successful induction was gestational age at delivery (p = 0.001), while induction for non-reassuring fetal testing was inversely associated (p = 0.02). Induction attempt, failed induction and delivery mode were not associated with increased neonatal morbidity. CONCLUSIONS: In women with severe pre-eclampsia remote from term, attempted labor induction did not appear to increase neonatal morbidity, but was rarely successful at < 28 weeks.

Adult↗
PubMed2000

Sevoflurane versus propofol for anesthetic induction: a meta-analysis.

UNLABELLED: We performed this meta-analysis to compare the characteristics of sevoflurane and propofol for the induction of routine anesthesia and for laryngeal mask airway (LMA) insertion. The variables assessed were 1) time to loss of consciousness, 2) incidence of apnea during induction, 3) induction complications, 4) time for successful LMA insertion, 5) success with LMA insertion on first attempt, 6) patient dissatisfaction, and 7) postoperative nausea and vomiting. MEDLINE, Embase, and the Cochrane library databases between January 1992 and October 1999 were reviewed for randomized, controlled trials comparing anesthetic induction between sevoflurane/nitrous oxide and propofol. Data from the 12 randomized, controlled studies were used for the meta-analysis. Sevoflurane induction was associated with a trend toward higher patient dissatisfaction and higher first-time success with LMA. Apnea was less common in the sevoflurane group. The incidence of postoperative nausea and vomiting was significantly more frequent in the sevoflurane group (P < 0.05). This effect was still present when all other variables, except the induction methods, were controlled. The other pooled variables did not show a significant difference between sevoflurane and propofol. Sevoflurane and propofol had similar efficacy for anesthetic induction. However, for routine outpatient surgery, propofol may still be the preferred induction anesthetic because of its favorable induction of anesthesia characteristics, high patient satisfaction, and less frequent incidence of postoperative nausea and vomiting. IMPLICATIONS: Sevoflurane and propofol had similar efficacy for anesthetic induction. However, for routine outpatient surgery, propofol may still be the preferred induction anesthetic because of its favorable induction of anesthesia characteristics, high patient satisfaction, and less frequent incidence of postoperative nausea and vomiting.

Anesthesia↗
PubMed2003

Association of the type of induction immunosuppression with posttransplant lymphoproliferative disorder, graft survival, and patient survival after primary kidney transplantation.

BACKGROUND: The use of antilymphocyte antibodies for induction therapy or for treatment for rejection has been associated with an increased risk of posttransplant lymphoproliferative disorder (PTLD). The authors investigated the incidence of PTLD after monoclonal antilymphocyte, polyclonal antilymphocyte, interleukin (IL)-2 receptor antibody, or no induction therapy in primary kidney transplant recipients. METHODS: A multivariate Cox analysis of 38,519 primary kidney transplants from January 1, 1997, to December 31, 2000, was performed to compare the incidence of PTLD, graft survival, and patient survival among the induction groups. RESULTS: The actual incidence of PTLD was 0.85% in 2,713 recipients with monoclonal, 0.81% in 4,343 with polyclonal, 0.50% in 7,800 with IL-2, and 0.51% in 23,663 recipients with no induction therapy (P=0.02). The Cox model indicated that as compared with no induction, the increased risk of PTLD was 72% with monoclonal (P=0.03), 29% with polyclonal (P=0.27), and 14% with IL-2 induction (P=0.52). IL-2 receptor antibody was associated with a 17% reduced risk of graft loss (P=0.002) and a 21% reduced risk of mortality (P=0.005) compared with no induction. Monoclonal and polyclonal induction therapies were not associated with a reduced risk of graft loss or mortality. Mycophenolate mofetil discharge maintenance immunosuppression was associated with a significantly reduced risk of PTLD and graft loss compared with azathioprine. CONCLUSIONS: Among induction therapies, IL-2 receptor antibody induction was associated with the smallest risk of PTLD and improved graft and patient survival. Monoclonal or polyclonal induction was not associated with improved graft or patient survival, and monoclonal induction was associated with an increased risk of PTLD.

Adolescent↗
PubMed2001

Induction of long-term depression in cerebellar Purkinje cells requires a rapidly turned over protein.

Evidence is presented indicating that the induction of long-term depression (LTD) in Purkinje cells (PCs) requires a rapidly turned over protein(s) during a critical time period within 15 min after the onset of LTD-inducing stimulation and that synthesis of this protein is maintained by mRNAs supplied via transcription. LTD was induced in granule cell axon (GA)-to-PC synapses by stimulation of these synapses at 1 Hz for 5 min in conjunction with the climbing fibers (CFs) forming synapses on the same PCs and represented by a persistent reduction in the GA-induced excitatory postsynaptic potentials (EPSPs). Not only a prolonged but also a brief (5 min) pulse application of translational inhibitors (anisomycin, puromycin, or cycloheximide) effectively blocked the LTD induction. Pulses applied during the period from 30 min before to 10 min after the onset of conjunctive stimulation blocked the LTD induction, but those applied 15 min after were ineffective. The three translational inhibitors blocked the LTD induction similarly, suggesting that the effect is due to their common action of inhibiting protein synthesis. Infusion of a mRNA cap analogue (7-methyl GTP) into PCs also blocked LTD induction, ensuring that the postsynaptic protein synthesis within PCs is required for LTD induction. Transcriptional inhibitors, actinomycin D and 5,6-dichloro-l-beta-D-ribofuranosyl-benzimidazole, also blocked the LTD induction, but this effect was apparent when 5-min pulses of the transcriptional inhibitors preceded the conjunctive stimulation by 30 min or more. This time lag of 30 min is presumed to be required for depletion of the protein(s) required for LTD induction. The presently observed effects of translational and transcriptional inhibitors on the LTD induction are of temporal characteristics corresponding to their depressant effects on the type-1 metabotropic glutamate-receptor (mGluR1)-mediated slow EPSPs in PCs as we have reported recently. An antagonist of mGluR1s [(RS)-1-aminoindan-1,5-dicarboxylic acid], however, did not block LTD induction when it was applied during the 10-min period following conjunctive stimulation, where translational inhibitors effectively blocked LTD induction. This discrepancy in time course suggests that the rapidly turned over protein(s) required for LTD induction is involved in a process occurring downstream of the activation of mGluR1s.

Animals↗
PubMed2004

Transvaginal ultrasonography for cervical assessment before induction of labor.

OBJECTIVE: To evaluate the value of ultrasonographic cervical assessment in predicting the outcome of labor induction and to compare its performance against the Bishop score. METHODS: The Bishop score was determined by digital examination, and transvaginal ultrasonography was performed in 105 women at 37 to 42 weeks' gestation scheduled for labor induction. Ultrasonographic parameters evaluated were cervical length, the presence of funneling, funnel width, and funnel length and were blinded to managing physicians. The primary outcome was the occurrence of active labor within 2 days (successful labor induction). The interval from the onset of induction to active labor (duration of induction) was the secondary outcome. Statistical analysis was performed by the chi2 test, Wilcoxon rank sum test, Pearson correlation, receiver operating characteristic curves, logistic regression, Cox proportional hazards model, and generalized Wilcoxon test for survival data. RESULTS: Induction of labor was successful in 93 women (89%). The area under the receiver operating characteristic curve for cervical length was greater than that of the Bishop score in predicting a successful labor induction (z = 2.18; P < .05). A cervical length of 3.0 cm or less had sensitivity of 75% (70 of 93) and specificity of 83% (10 of 12). Multiple logistic regression analysis showed a significant relationship between successful labor induction and cervical length but not the Bishop score (odds ratio = 0.24; 95% confidence interval, 0.096-0.59; P = .002). Only parity and cervical length had a significantly independent relationship with the duration of induction. CONCLUSIONS: Cervical length measured by transvaginal ultrasonography is a useful and independent predictor of successful labor induction and the duration of induction and provides better predictability of successful labor induction than the Bishop score does.

Adult↗
PubMed1999

[Using of Misoprostol for preinduction and induction of labor in term pregnancy].

UNLABELLED: Labour induction is frequently indicated in women with an unfavourable cervix. Oxytocin and prostaglandins are the most common drugs used for labour induction. Induction of labour with prostaglandins offers the advantage of promoting both cervical ripening and myometrial contractility. The purpose of the study was to evaluate the safety and efficacy intravaginal administration prostaglandin E1 methyl analogue, misoprostol in cervical ripening and induction of labour in term pregnancy and in women with unfavourable cervix (Bishop score < = 4). The approval for this study was given by the Board of Medical Ethics, University Medical School of Lublin in Poland. MATERIALS AND METHODS: 64 women with indication for termination of pregnancy received either misoprostol (Cytotec-Searle) vaginally (group M, n = 30) or intravenous drip infusion of oxytocin(group Ox, n = 34). We evaluated profile of the studied women (gravidity, weight, height, maternal age, gestational age), effectiveness and safety of the misoprostol and need for oxytocin administration in group M, start of induction-to-active labour interval (contractions), start of induction-to-vaginal delivery interval, hyperstimulation syndrome, delivery within 24 hours of drug application and caesarean section rate. Before starting labour induction a Bishop score was obtained. Statistical analysis was performed. Baseline and outcome variables were tested with student's t-test and c2 analysis. We needed p < 0.05 for statistical significance. RESULTS: There were no differences in the patient profiles (gravidity, weight, height, maternal age, gestational age) between groups except the score of cervical ripening. The Bishop score before induction was lower in group M. The interval between the initiation of induction to active labour was shorter in the misoprostol group (334.23 +/- 126.35 versus 610.00 +/- 352.14 minutes). The mean time between the initiation of induction to delivery was shorter in group M (707.69 +/- 341.15 +/- versus 1025.77 +/- 369.16 minutes). These differences were statistically significant. 28 (93.33%) patients in the misoprostol group delivered within 24 hours compared with 24 (70.59%) women in the oxytocin group. 8 patients in the misoprostol group and 8 patient in the oxytocin group had caesarean section. Labor induction was successful in 30 (100%) women in the misoprostol group compared with 24 (70.59%) patients in the group Ox. CONCLUSIONS: Intravaginal misoprostol is an effective, easy to use and cheap drug for the induction of labour, especially for cervical ripening in women with unfavourable cervix (Bishop score < = 4).

Administration, Intravaginal↗
PubMed2001

Remission induction therapy: the more intensive the better?

Intensive induction therapy in acute myeloid leukemia (AML) as in some other systemic malignancies is a strategy fundamentally different from post-remission strategies. Approaches such as consolidation treatment, prolonged maintenance, and autologous or allogeneic transplantation in first remission are directed against the minimal residual disease in which a malignant cell population has survived induction treatment and shows resistance due to special genetic or kinetic features. In contrast, induction therapy deals with naive tumor cells possibly different from their counterparts in remission in terms of their kinetic status and sensitivity. Therefore, in AML the introduction of intensification strategies into the induction phase of treatment has been suggested as a new step in addition to intensification in the postremission phase. As expected from the dose effects observed in post-remission treatment with high-dose cytarabine (AraC) or longer treatment, similar dose effects have been found in induction treatment both from the incorporation of high-dose AraC and from the double-induction strategy used in patients up to 60 years of age. As a particular effect, patients with poor-risk AML according to an unfavorable karyotype, high LDH in serum, or a delayed response show longer survival following double induction containing high-dose AraC as compared to standard-dose AraC. A corresponding dose effect in the induction treatment of patients aged 60 years and older has been found with daunorubicin 60 vs 30 mg/m2 as part of the thioguanine/ AraC/daunorubicin (TAD) regimen with the higher dosage significantly increasing the response rate and survival in these older patients who represent a poor-risk group as a whole. Thus we have been able to demonstrate both in younger and older patients that a poor prognosis can be improved by a more intensive induction therapy. High-dose AraC in induction, however, exhibits cumulative toxicity in that repeated courses containing high-dose AraC in the post-remission period lead to long-lasting aplasias of about 6 weeks. Thus after intensive induction treatment, high-dose chemotherapy in remission may be practicable using stem-cell rescue and may contribute to a further improvement in the outcome in poor-risk as well as average-risk patients with AML. These approaches are currently under investigation by the German AML Cooperative Group (AMLCG). "The more intensive the better" is certainly not the way to go in the management of AML and other systemic malignancies but some increase in intensity may be possible and better.

Acute Disease↗
PubMed1981

The induction of ornithine decarboxylase by nerve growth factor and epidermal growth factor in PC12 cells.

Both nerve growth factor and epidermal growth factor cause an induction of ornithine decarboxylase in the rat pheochromocytoma clone PC12. The induction by nerve growth factor is transcription-dependent and occurs within 4 to 6 h. Antibody studies indicate that nerve growth factor must be present for 2-3 h to obtain full induction. Nerve growth factor is synergistic with either N6, O2-dibutyryl cyclic 3',5'-adenosine monophosphate (dBcAMP) or 3-isobutyl-1-methylxanthine (IBMX) in the induction. The magnitude of ornithine decarboxylase induction is influenced by the density of the culture. Synchronized cell populations show the greatest sensitivity to nerve growth factor just before, or immediately upon, entering S phase. The induction of ornithine decarboxylase by epidermal growth factor appears to be quite similar to that exhibited by nerve growth factor. Epidermal growth factor is active in the range of ng/ml. The time course of the induction is the same, as is the need for the peptide to remain in contact with the cells for several hours. Putrescine inhibits the induction and dBcAMP and IMBX accentuate it. Cells appear to be sensitive to epidermal growth factor also near the G1/S border. In spite of the marked similarities in these inductions, a maximal level of nerve growth factor plus a maximal level of epidermal growth factor yields greater induction than either alone, indicating the inductions occur by somewhat different mechanisms.

Adrenal Gland Neoplasms↗
PubMed1981

Differential retinoic acid inhibition of ornithine decarboxylase induction by 12-O-tetradecanoylphorbol-13-acetate and by germicidal ultraviolet light.

Several retinoids including retinoic acid effectively inhibit phorbol ester-mediated tumor promotion and ornithine decarboxylase (ODC) induction in mouse epidermis. To understand better the possible cellular site of action of retinoids, the inhibitory action of retinoic acid on the induction of ODC was compared for two distinctly different inducers, namely, 12-O-tetradecanoylphorbol-13-acetate (TPA) and germicidal ultraviolet light (UV), in primary mouse epidermal cell cultures. It was found that the induction of ODC by TPA is almost completely prevented by 0.1 to 1 microM retinoic acid while the induction by UV is only moderately inhibited. Maximum inhibition is achieved by treating cells continuously with retinoic acid from 4 hr after plating, although pretreatment or simultaneous treatment relative to either inducer is almost as effective. When added after the inducer, retinoic acid loses its effectiveness as an inhibitor more rapidly for TPA induction than for UV induction of ODC. The differential inhibition of enzyme induction cannot be accounted for by selective retinoid inhibition of DNA, RNA, or protein synthesis either alone or in concert with TPA or UV. Other agents known to modulate the induction of ODC by TPA (fluocinolone acetonide, tosyl-L-lysylchloromethane, and local anesthetics) do not act differentially on UV induction. These agents possibly act at transcription or translation, both of which are required for ODC induction by TPA or UV. The preferential inhibition by retinoic acid of ODC induction by TPA is interpreted to result from specific interference at a unique and early site of interaction of TPA with the cell.

Animals↗
PubMed2000

Amniotomy alone for induction of labour.

BACKGROUND: Amniotomy (deliberate rupture of the membranes) is a simple procedure which can be used alone for induction of labour if the membranes are accessible, thus avoiding the need for pharmacological intervention. However, the time interval from amniotomy to established labour may not be acceptable to clinicians and women, and in a number of cases labour may not ensue. This is one of a series of reviews of methods of cervical ripening and labour induction using standardised methodology. OBJECTIVES: To determine the effects of amniotomy alone for third trimester labour induction in women with a live fetus. SEARCH STRATEGY: The Cochrane Pregnancy and Childbirth Group trials register, the Cochrane Controlled trials register and bibliographies of relevant papers. SELECTION CRITERIA: The criteria for inclusion included the following: (1) clinical trials comparing amniotomy alone for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed above it on a predefined list of labour induction methods; (2) random or pseudo-random allocation to the treatment or control group; (3) ideally adequate allocation concealment (4) violations of allocated management not sufficient to materially affect conclusions; (5) clinically meaningful outcome measures reported; (6) data available for analysis according to the random allocation; (7) missing data insufficient to materially affect the conclusions. DATA COLLECTION AND ANALYSIS: This is one of a series of reviews of methods of cervical ripening and labour induction using standardised methodology. A strategy was developed to deal with the large volume and complexity of trial data relating to labour induction. This involved a two-stage method of data extraction. The initial data extraction was done centrally, and incorporated into the series of primary reviews arranged by methods of induction of labour. The data from the primary reviews will be incorporated into a series of secondary reviews, arranged by category of woman to reflect clinical scenarios. To avoid duplication of data in the primary reviews, the labour induction methods have been listed in a specific order, from one to 25. Each primary review includes comparisons between one of the methods (from two to 25) with only those methods above it on the list. This review includes comparisons between amniotomy alone (number 5 on the list) with only those methods above it on the list (no treatment / placebo; intravaginal prostaglandins; intracervical prostaglandins; and oxytocin alone). MAIN RESULTS: Two trials comprising 50 and 260 women respectively were eligible for inclusion in this review. No conclusions could be drawn from comparisons of amniotomy alone versus no intervention, and amniotomy alone versus oxytocin alone (small trial, only one pre-specified outcome reported). No trials compared amniotomy alone with intracervical prostaglandins. One trial compared amniotomy alone with a single dose of vaginal prostaglandins for women with a favourable cervix, and found a significant increase in the need for oxytocin augmentation in the amniotomy alone group (44% versus 15%; RR 2.85, 95% CI 1.82-4.46). This should be viewed with caution as this was the result of a single centre trial. Furthermore, secondary intervention occurred 4 hours after amniotomy, and this time interval may not have been appropriate. REVIEWER'S CONCLUSIONS: Data is lacking about the value of amniotomy alone for induction of labour. While there are now other modern methods available for induction of labour (pharmacological agents), there remain clinical scenarios where amniotomy alone may be desirable and appropriate, and this method is worthy of further research. This research should include evaluation of the appropriate time interval from amniotomy to secondary intervention, women and caregivers' satisfaction and economic analysis.

Amnion↗
PubMed2001

Amniotomy plus intravenous oxytocin for induction of labour.

BACKGROUND: Induction of labour is a common obstetric intervention. Amniotomy alone for induction of labour is reviewed separately and oxytocin alone for induction of labour is being prepared for inclusion in The Cochrane Library. This review will address the use of the combination of these two methods for induction of labour in the third trimester. This is one of a series of reviews of methods of cervical ripening and labour induction using standardised methodology. OBJECTIVES: To determine, from the best available evidence, the efficacy and safety of amniotomy and intravenous oxytocin for third trimester induction of labour. SEARCH STRATEGY: The Cochrane Pregnancy and Childbirth Group Trials Register, the Cochrane Controlled Trials Register and reference lists of articles were searched. Date of last search: May 2001. SELECTION CRITERIA: The criteria for inclusion included the following: (1) clinical trials comparing amniotomy plus intravenous oxytocin used for third trimester cervical ripening or labour induction with placebo/no treatment or other methods listed above it on a predefined list of labour induction methods; (2) random allocation to the treatment or control group; (3) adequate allocation concealment; (4) violations of allocated management not sufficient to materially affect conclusions; (5) clinically meaningful outcome measures reported; (6) data available for analysis according to the random allocation; (7) missing data insufficient to materially affect the conclusions. DATA COLLECTION AND ANALYSIS: Trial quality assessment and data extraction were done by both reviewers. A strategy was developed to deal with the large volume and complexity of trial data relating to labour induction. This involved a two-stage method of data extraction. The initial data extraction was done centrally, and incorporated into a series of primary reviews arranged by methods of induction of labour, following a standardised methodology. The data is to be extracted from the primary reviews into a series of secondary reviews, arranged by category of woman. MAIN RESULTS: Seventeen trials involving 2566 women were included. Amniotomy and intravenous oxytocin were found to result in fewer women being undelivered vaginally at 24 hours than amniotomy alone (relative risk (RR) 0.03, 95% confidence intervals (CI) 0.001-0.49). This finding was based on the results of a single study of 100 women. As regards secondary results amniotomy and intravenous oxytocin resulted in significantly fewer instrumental vaginal deliveries than placebo (RR 0.18, CI 0.05-0.58). Amniotomy and intravenous oxytocin resulted in more postpartum haemorrhage than vaginal prostaglandins (RR 5.5, CI 1.26-24.07). Significantly more women were also dissatisfied with amniotomy and intravenous oxytocin when compared with vaginal prostaglandins, RR 53, CI 3.32-846.51. REVIEWER'S CONCLUSIONS: Data on the effectiveness and safety of amniotomy and intravenous oxytocin are lacking. No recommendations for clinical practice can be made on the basis of this review. Amniotomy and intravenous oxytocin is a combination of two methods of induction of labour and both methods are utilised in clinical practice. If their use is to be continued it is important to compare the effectiveness and safety of these methods, and to define under which clinical circumstances one may be preferable to another.

Amnion↗
PubMed2004

Does ultrasound examination when the cervix is unfavorable improve the prediction of failed labor induction?

OBJECTIVE: To compare the Bishop score, ultrasound cervical parameters and fetal fibronectin assessment for predicting failed labor induction when the cervix is unfavorable. METHOD: A prospective observational study was performed in 106 consecutive pregnant women with a Bishop score < or =5 undergoing labor induction. Assessment of fetal fibronectin and ultrasound measurement of cervical length, cervical wedging and cervical lip areas were performed. The relationship between these parameters and failure of labor induction was determined. RESULTS: Failure of labor induction was defined as failure to reach a cervical dilatation of > or =5 cm, and it occurred in 16 patients (15.1%). Induction failure was associated with low Bishop scores before (P = 0.004) and 6 h after the start of induction (P = 0.007), increased clinical cervical length (P = 0.02) and increased ultrasound anterior cervical lip area (P = 0.04). The logistic regression model identified the Bishop score before induction (odds ratio = 2.25; 95% CI, 1.30-3.91; P = 0.003) and the clinical cervical length (odds ratio = 3.95; 95% CI, 1.3-11.7; P = 0.01) as being independent predictors of failed induction. To predict an induction failure, the best Bishop score cut-off value was 4, with a sensitivity of 87.5%, a specificity of 45.6%, a likelihood ratio of 1.58, a positive predictive value of 22.2% and a negative predictive value of 95.4%. CONCLUSION: Compared with the Bishop score, cervical length by ultrasound is not a better predictor for the outcome of labor induction in an unfavorable cervix. Nevertheless, the Bishop score appears to be of poor predictive value for failed induction of labor.

Adult↗