Simultaneous determination of flupyrazofos and its metabolite 1-phenyl-3-trifluoromethyl-5-hydroxypyrazole and flupyrazofos oxon in rat plasma by high-performance liquid chromatography with ultraviolet absorbance detection

An isocratic high-performance liquid chromatography (HPLC) system with UV detection was developed for simultaneous determination of flupyrazofos and its metabolites, 1-phenyl-3-trifluoromethyl-5-hydroxypyrazole and flupyrazofos oxon, in rat plasma. Optimal analytical conditions involved an analytical cartridge column consisting of a phenyl bonded phase, a mobile phase of 50 mM phosphate buffer (pH3.0)-acetonitrile (40:60, v/v) and a UV detection wavelength of 232 nm. Under these conditions the peaks of flupyrazofos and its metabolites were all well separated and the total time for complete separation was less than 12 min. The limit of quantitation was 40 ng/ml for flupyrazofos and 20 ng/ml for PTMHP. Recoveries from rat plasma were higher than 90%. Following intravenous administration of flupyrazofos, the method has been successfully applied in a toxicokinetic study in rats involving plasma samples. Therefore, the current method is a valuable analytical tool for investigating the metabolism and toxicokinetics of flupyrazofos.

Effects of beta-ionone on the expression of cytochrome P450s and NADPH-cytochrome P450 reductase in Sprague Dawley rats

We have recently reported that beta-ionone induces cytochrome P450 (P450) 2B1 in rats. Effects of beta-ionone on the expression of other P450 isozymes and NADPH-P450 reductase were further investigated in Sprague Dawley rats. Administration of beta-ionone subcutaneously 72 and 48 h before sacrificing the animals not only significantly induced the liver microsomal activities of P450-associated enzymes and NADPH-P450 reductase, but also clearly increased in the level of P450 1A1/2, P450 2C, and NADPH-P450 reductase proteins. The induction of P450 1A1/2 and 2C by beta-ionone was much greater in male than in female as measured by western immunoblotting. Reverse transcriptase-polymerase chain reactions showed that, in addition to P450 2B1 and 2B2 mRNAs, P450 1A2, 2C6 and NADPH-P450 reductase mRNAs were increased when beta-ionone was administered. Our previous and present results indicated that beta-ionone may induce several P450s and NADPH-P450 reductase by the accumulation of their corresponding mRNAs.

Pharmacokinetic analysis for assessing developmental toxicity of a new synthetic acetolactate synthase inhibitor, LGC-40863, in rats

Effects of O-[2,6-bis[(4,6-dimethoxy-2pyrimidinyl)oxy]benzoyl]oxime (LGC-40863) on dams and embryonic development were examined at p.o. doses of 500, 1000 and 2000 mg/kg/day on days 6 to 15 of gestation in rats. No significant maternal or embryonic toxicity was observed at any of the doses. However, external fetal anomalies including brachycephaly, microcephaly, micrognathia, agnathia, lordosis and edema were observed at an incidence of 2.2% at the lowest dosage level but not at higher dosages. Because these malformations are not common as spontaneous variations in rats, we carried out a toxicokinetic study to clarify whether the fetal anomalies at 500 mg/kg are related to LGC-40863. During multiple p.o. administrations of LGC-40863 at the same doses used in the developmental toxicity study, LGC-40863 was not detected in the systemic circulation. Moreover, 3 months of multiple dosing did not alter its plasma level. In the pregnant rats receiving 500 mg/kg on 10 consecutive days of gestation, LGC-40863 was also undetectable. However, after i.v. administration, high levels of the drug were found in plasma, and these could be described by a two-compartment model. These results demonstrate that the bioavailability of LGC-40863 is negligible. To investigate a possible relevance of metabolite(s) to the fetal anomalies, we examined excretion of radioactivity after p.o. doses of 500 and 2000 mg/kg of LGC-40863 spiked with [14C]LGC-40863. For both doses, cumulative recovery up to 72 hr was approximately 80% and 9% in feces and urine, respectively, indicating dose linearity in the elimination kinetics. Overall, these toxicokinetic data suggest that the fetal anomalies observed at 500 mg/kg are not associated with LGC-40863 but are spontaneously generated. In conclusion, LGC-40863 had neither significant maternal nor developmental toxicity at any of the doses tested for p.o. exposure.

Mapping of new recessive cataract gene (lr2) in the mouse

A new strain of mice with cataracts was developed in BALB/cHeA and STS/A recombinant inbred strain, CXS4 (D). In this study the mapping of spontaneous autosomal recessive cataract mutation is described. This mutation was characterized by ruptures of the lens nucleus, vitreous chamber through the posterior capsule, and the vacuolization of the lens. For the linkage analysis, we produced two kinds of backcross progenies, (BALB/cHeA x D)F1 and (STS/A x D)F1 females crossed to D male mice. The gene (lr2, lens rupture2) was mapped to the central part of Chromosome(Chr) 14, 0.7 +/- 0.7 cM from the micosatellite marker D14Mit28.

Role of Egr-1 gene expression in B cell receptor-induced apoptosis in an immature B cell lymphoma

Ligation of B cell receptor (BCR) on BKS-2, an immature B cell lymphoma by anti-IgM antibodies (Ab) caused apoptosis. Here we report that signaling through B cell receptor in wild type BKS-2 cells down-regulated the expression of Egr-1, a zinc finger-containing transcription factor. A reduction in the level of Egr-1 mRNA could be demonstrated as early as 30 min after the ligation of BCR on BKS-2 cells. Immunocytochemical and Western blot analysis revealed that the expression of EGR-1 protein was also inhibited by anti-IgM treatment. Antisense oligonucleotides to Egr-1 caused growth inhibition and apoptosis in BKS-2 cells, suggesting that expression of Egr-1 is important for the survival of these B lymphoma cells. In contrast to wild type BKS-2 cells, the mutant 1. B5 cell line, which is refractory to B cell receptor-mediated growth-inhibitory signals, showed an increased expression of Egr-1 upon treatment with anti-IgM. These results implicate a role for Egr-1 in blocking B cell receptor-mediated apoptosis in immature B cells.

Prevention of ultraviolet radiation-induced suppression of accessory cell function of Langerhans cells by Aloe vera gel components

The active components of Aloe vera gel that can prevent ultraviolet B (UVB)-induced suppression of accessory cell function of Langerhans cells (LC) were purified by activity-guided sequential fractionation followed by in vitro functional assay. The functional assay was based on the fact that exposure of freshly isolated murine epidermal cells (EC) to UVB radiation resulted in impairment of accessory cell function of LC, as measured by their ability to support anti-CD3 monoclonal antibody (mAb)-primed T-cell mitogenesis. This UVB-suppressed LC accessory cell function was prevented by addition of partially purified Aloe gel components to cultures of UVB-irradiated EC. The Aloe gel components appeared to prevent events occurring within the first 24 h after UVB irradiation that lead to the impairment of accessory cell function. The Aloe gel components did not cause proliferation of anti-CD3 mAb-primed T-cells, nor did induce proliferation of normal EC. The activity-guided final purification of Aloe gel components resulted in the isolation of two components. Both of the components were small molecular weight (MW) substances with an apparent MW of less than 1,000 Da but different from each other in net charge characteristics at pH 7.4. These results suggest that Aloe vera gel contains at least two small molecular weight immunomodulators that may prevent UVB-induced immune suppression in the skin.

Early growth response-1-dependent apoptosis is mediated by p53

The early growth response-1 (EGR-1) protein is an anti-proliferative signal for certain tumor cells and is required for apoptosis induced by stimuli that elevate intracellular Ca2+. We present evidence that EGR-1 transactivates the promoter of the p53 gene and up-regulates p53 RNA and protein levels. Inhibition of p53 function with dominant-negative p53 mutants abrogates EGR-1-dependent apoptosis. These findings establish a direct functional link between EGR-1 and the p53-mediated cell death pathway and suggest that mutant forms of p53 in tumor cells may provide resistance to the anti-proliferative effects of EGR-1.

A new hereditary cataract mouse with lens rupture

A new cataract model originated in a recombinant inbred (RI) strain, CXS4 or CXSD (D), between BALB/cHeA(BALB/c or C) and STS/A(STS or S) mice. Opacity appeared as a white pinpoint focus in unpigmented eyes of albino mice from 5 weeks old. All the mice were bilaterally affected by 14 weeks old. They were fully viable and fertile. There was no sex difference in incidence of cataract. Histologically, the 3-4 months old mice showed vacuoles in the lens cortex. The vacuoles were spread all over the lens cortex in advanced cases. Ruptures of the lens nucleus to the vitreous chamber was a typical occurrence. For elucidation of the mode of inheritance, F1 hybrids (CXD and SXD) and backcross progenies [(CXD)F1XD and (SXD)F1XD] were analysed. No affected mice were observed in F1 hybrids. In backcross progenies, the segregation ratio of affected and normal mice was close to 1:1 in both matings. We conclude that the cataract is inherited by an autosomal single recessive gene. This mutant gene is provisionally named 'lens rupture 2' (gene symbol 1r2, Mouse Genome Database Accession No. MGD-JNUM-37399). The new cataract model mouse will be a good tool for the genetic analysis and molecular biological study of cataractogenesis.

Expression and function of the leucine zipper protein Par-4 in apoptosis

The prostate apoptosis response-4 (par-4) gene was identified by differential screening for genes that are upregulated when prostate cancer cells are induced to undergo apoptosis. The par-4 gene is induced by apoptotic signals but not by growth-arresting, necrotic, or growth-stimulatory signals. The deduced amino acid sequence of par-4 predicts a protein with a leucine zipper domain at its carboxy terminus. We have recently shown that the Par-4 protein binds, via its leucine zipper domain, to the zinc finger domain of Wilms' tumor protein WT1 (R. W. Johnstone et al., Mol. Cell. Biol. 16:6945-6956, 1996). In experiments aimed at determining the functional role of par-4 in apoptosis, an antisense par-4 oligomer abrogated par-4 expression and activator-driven apoptosis in rat prostate cancer cell line AT-3, suggesting that par-4 is required for apoptosis in these cells. Consistent with a functional role for par-4 in apoptosis, ectopic overexpression of par-4 in prostate cancer cell line PC-3 and melanoma cell line A375-C6 conferred supersensitivity to apoptotic stimuli. Transfection studies with deletion mutants of Par-4 revealed that full-length Par-4, but not mutants that lacked the leucine zipper domain of Par-4, conferred enhanced sensitivity to apoptotic stimuli. Most importantly, ectopic coexpression of the leucine zipper domain of Par-4 inhibited the ability of Par-4 to enhance apoptosis. Finally, ectopic expression of WT1 attenuated apoptosis, and coexpression of Par-4 but not a leucine zipperless mutant of Par-4 rescued the cells from the antiapoptotic effect of WT1. These findings suggest that the leucine zipper domain is required for the Par-4 protein to function in apoptosis.

More of what? Issues raised by the Fort Bragg study

The sobering findings of the Fort Bragg study illustrate why ambitious demonstration projects must be combined with objective outcome evaluations. The study does suggest that "more is not always better" (L Bickman, 1996), but more of what? Little is known about the specific interventions that were combined to form the Fort Bragg system of care, so the study does not really reveal what failed or what needs to be changed. Moreover, there is no evidence that the specific treatments used had any empirical support. Combining and systematizing various treatments may not produce improved outcomes if the treatments are not effective in the first place. Costly demonstration programs that combine untested treatments may be a poor investment. A better strategy may be to develop and test an array of well-documented treatments for an array of child and family problems, creating the building blocks needed for effective systems of care in the future.

Anti-IL-4 monoclonal antibody prevents antibiotics-induced active fatal anaphylaxis

We previously reported that anti-IL-4 mAb (11B11) failed to prevent protein-induced fatal murine anaphylaxis. To investigate the effect of anti-IL-4 on hapten-induced anaphylaxis, a model of murine anaphylaxis induced by antibiotics, penicillin V (Pen V) and cephalothin (CET), was developed, and the effect of anti-IL-4 on the anaphylaxis was observed. Pen V and CET induced 100 and 70 to 90% fatal reactions, respectively, when C57BL/6 mice were sensitized i.p. with 500 microg of antibiotic-OVA conjugate with 2 x 10(9) Bordetella pertussis and 1.0 mg of alum and challenged i.v. with 100 microg of antibiotic-BSA conjugate 14 days later. Serum taken from mice sensitized to Pen V passively sensitized normal mice to develop systemic anaphylaxis, and this ability of the serum was abrogated by heating at 56 degrees C for 2 h or depletion of IgE, but not IgG, Abs. Thus, the antibiotic-induced fatal reaction was an IgE-dependent anaphylactic reaction. Administration of anti-IL-4 at the beginning of sensitization completely prevented the fatal anaphylactic reactions to both Pen V and CET. This effect of anti-IL-4 was associated with its suppressive activity on antibiotic-specific serum IgE, but not IgG, levels. More importantly, anti-IL-4 therapy in previously sensitized mice was also effective in preventing the fatal reactions and rapidly reduced the established IgE levels. This study provides a new animal model of hapten-induced anaphylaxis and indicates that blocking of IL-4 activity may be beneficial in allergic diseases caused by a variety of haptens in which IgE Abs play a major role.

Anti-IL-4 monoclonal antibody prevents antibiotics-induced active fatal anaphylaxis

We previously reported that anti-IL-4 mAb (11B11) failed to prevent protein-induced fatal murine anaphylaxis. To investigate the effect of anti-IL-4 on hapten-induced anaphylaxis, a model of murine anaphylaxis induced by antibiotics, penicillin V (Pen V) and cephalothin (CET), was developed, and the effect of anti-IL-4 on the anaphylaxis was observed. Pen V and CET induced 100 and 70 to 90% fatal reactions, respectively, when C57BL/6 mice were sensitized i.p. with 500 microg of antibiotic-OVA conjugate with 2 x 10(9) Bordetella pertussis and 1.0 mg of alum and challenged i.v. with 100 microg of antibiotic-BSA conjugate 14 days later. Serum taken from mice sensitized to Pen V passively sensitized normal mice to develop systemic anaphylaxis, and this ability of the serum was abrogated by heating at 56 degrees C for 2 h or depletion of IgE, but not IgG, Abs. Thus, the antibiotic-induced fatal reaction was an IgE-dependent anaphylactic reaction. Administration of anti-IL-4 at the beginning of sensitization completely prevented the fatal anaphylactic reactions to both Pen V and CET. This effect of anti-IL-4 was associated with its suppressive activity on antibiotic-specific serum IgE, but not IgG, levels. More importantly, anti-IL-4 therapy in previously sensitized mice was also effective in preventing the fatal reactions and rapidly reduced the established IgE levels. This study provides a new animal model of hapten-induced anaphylaxis and indicates that blocking of IL-4 activity may be beneficial in allergic diseases caused by a variety of haptens in which IgE Abs play a major role.

More of what? Issues raised by the Fort Bragg study

The sobering findings of the Fort Bragg study illustrate why ambitious demonstration projects must be combined with objective outcome evaluations. The study does suggest that "more is not always better" (L Bickman, 1996), but more of what? Little is known about the specific interventions that were combined to form the Fort Bragg system of care, so the study does not really reveal what failed or what needs to be changed. Moreover, there is no evidence that the specific treatments used had any empirical support. Combining and systematizing various treatments may not produce improved outcomes if the treatments are not effective in the first place. Costly demonstration programs that combine untested treatments may be a poor investment. A better strategy may be to develop and test an array of well-documented treatments for an array of child and family problems, creating the building blocks needed for effective systems of care in the future.

Titanium oxide film for the bottom antireflective layer in deep ultraviolet lithography

Titanium oxide thin film, fabricated with tetraisopropyltitanate and oxygen by electron cyclotron resonance-plasma-enhanced chemical vapor deposition, is investigated as a potential candidate for the antireflective layer in KrF excimer laser (248-nm) lithography. The oxygen flow-rate dependence of the optical properties such as the refractive index (n) and the extinction coefficient (k) of the film at the 248-nm wavelength has been characterized, and the films with the expected combinations of n and k values for the antireflective layer have been deposited. Simulation results indicate that reflectance values of less than 4% and as low as 1.2% can be reached at the interface between the photoresist and the film postulating the structures of the photoresist/300-A TiO(x) film/c-Si substrate and the W-Si substrate, respectively, by selected proper combinations of n and k values. Moreover the reflectance can be further reduced to almost zero by changing the film thickness. Thus it is found that titanium oxide thin films can be used as the bottom antireflective layer in KrF excimer laser lithography.

Enhancing effects of captafol on the development of GST-P-positive liver cell foci in a medium-term bioassay, and protection by L-cysteine of the enhancement in rats

The modifying effects of captafol and protective effects of L-cysteine on the development of glutathione S-transferase placental form-positive (GST-P +) foci of the liver and expression of proliferating cell nuclear antigen (PCNA) in the kidney were investigated in a medium-term bioassay using D-galactosamine (DGA) in rats. Male 6-week-old F344 rats were initially given a single i.p. injection (200 mg/kg) of diethylnitrosamine (DEN) and after 2 weeks on basal diet, received two i.p. injections of DGA (300 mg/kg) at the ends of weeks 2 and 5, and were fed a diet supplemented with test chemicals for weeks 3-8. Animals in group 1 were given 1500 ppm captafol in the diet, while group 2 received 1500 ppm captafol in diet as well as 1500 ppm L-cysteine in drinking water, animals in control group being given basal diet alone. Positive results regarding increased numbers and areas of GST-P + liver cell foci were obtained in rats treated with captafol alone. On the other hand, significant reduction by L-cysteine in the areas of GST-P + liver cell foci initiated by DEN and promoted by captafol was observed. In addition, the PCNA-labelling indices of renal tubule cells were elevated in rats treated with captafol alone and significantly reduced in rats treated simultaneously with L-cysteine. The protocol used in the present study therefore allowed the in vivo determination of promoting effects of captafol and inhibitory influence of L-cysteine by analyzing GST-P + foci in the livers as marker lesions, within a relatively short period of 8 weeks. Thus, this bioassay protocol could have applicability as a new in vivo assay system for the screening of hepatic carcinogenic or anti-carcinogenic agents.

Effects of ethyl carbamate and its metabolites on the antibody response in splenocyte cultures from female Balb/C mice

To investigate a possible role by cytochrome P450 (P450) in ethyl carbamate-induced immunosuppression, an attempt to assess the ability of ethyl carbamate, its metabolites produced by P450 (i.e., ethyl N-hydroxycarbamate and vinyl carbamate), and methyl carbamate to suppress the polyclonal antibody response induced by bacterial lipopolysaccharide was made in splenocyte cultures isolated from female Balb/C mice. The results showed that vinyl carbamate and ethyl N-hydroxycarbamate were more immunosuppressive compared to ethyl carbamate. A structurally related analogue, methyl carbamate, did not suppress the antibody response. These results indicate that metabolism of ethyl carbamate by P450 may produce more immunosuppressive metabolites as in ethyl carbamate-induced carcinogenicity. A pre-incubation study with phenobarbital-induced liver microsomes in the presence of NADPH-generating system showed that the antibody response was suppressed by ethyl carbamate when splenocytes were pre-incubated with ethyl carbamate and microsomes simultaneously. Moreover, the suppression was completely recovered by the addition of a P450 inhibitor, aminoacetonitrile, in the pre-incubation. Taken together, the present results indicate that metabolism of ethyl carbamate by P450 enzyme(s) may be an important pathway to cause immunosuppression.

Bridging the gap between laboratory and clinic in child and adolescent psychotherapy

Meta-analyses of laboratory outcome studies reveal beneficial effects of psychotherapy with children and adolescents. However, the research therapy in most of those lab studies differs from everyday clinic therapy in several ways, and the 9 studies of clinic therapy the authors have found show markedly poorer outcomes than research therapy studies. These findings suggest a need to bridge the long-standing gap between outcome researchers and clinicians. Three kinds of bridging research are proposed and illustrated: (a) enriching the research data base on treatment effects by practitioners in clinical settings--including private practice and health maintenance organizations, (b) identifying features of research therapy that account for positive outcomes and applying those features to clinical practice, and (c) exporting lab-tested treatments to clinics and assessing their effects with referred youths. If these bridging strategies were widely adopted, despite the numerous obstacles described herein, real progress might be made toward more effective treatment in clinical practice.

Role of metabolism in ethyl carbamate-induced suppression of antibody response to sheep erythrocytes in female Balb/C mice

A possible role of metabolism by cytochrome P450 (P450) in ethyl carbamate-induced suppression of the antibody response to a T-cell-dependent antigen, sheep erythrocytes (SRBCs), was investigated in female Balb/C mice. When mice were treated with ethyl carbamate intraperitoneally for 14 consecutive days at 25, 50, 100, 200 and 400 mg/kg, the antibody response was significantly suppressed from 200 mg/kg. These doses also caused a decrease in thymus weight. An acute dosing of ethyl carbamate at 1 g/kg also caused not only a significant suppression of the antibody response, but also a decrease in thymus weight. The antibody response was most likely to be the IgM antibody response, which was demonstrated in a haemagglutination study. When mice were pretreated with phenobarbital (80 mg/kg) for 3 days to induce P450 enzymes, followed by administration of ethyl carbamate intraperitoneally for 7 consecutive days, the antibody response was more suppressed than in saline-pretreated controls. Moreover, a study using aminoacetonitrile, a P450 inhibitor, showed that the antibody response suppressed by ethyl carbamate was completely recovered by the inhibitor. The present results suggest that metabolism of ethyl carbamate by P450 may be the critical pathway to produce metabolites capable of suppressing the antibody response.

Induction of liver cytochrome P450 2B1 by beta-ionone in Sprague Dawley rats

Induction of liver cytochrome P450 2B1 by beta-ionone was investigated in male and female Sprague Dawley rats. Administration of beta-ionone subcutaneously 72 and 48 hr before sacrificing the animals not only significantly induced the liver microsomal activity of pentoxyresorufin O-dealkylase, but also clearly increased in the level of cytochrome P450 2B1 protein. The induction of cytochrome P450 2B1 by beta-ionone was much greater in male rats than in female rats. A slot blot analysis showed that the mRNA level was increased from 6 hr after treatment with beta-ionone in male rats and from 12 hr after treatment in female rats. Taken together, the present results indicate for the first time that the induction of cytochrome P450 2B1 by beta-ionone might be regulated by the accumulation of mRNAs.

Cytogenetic study employing chorionic villi in ectopic pregnancy

Maternal factors such as salpingitis and peritubal adhesion are known to be associated with ectopic pregnancy; however, a few studies have considered the chromosomal complements of ectopic conceptuses. We studied 16 ectopic conceptuses obtained by surgical resection. The karyotyping of chorionic villi was performed using direct and culture technique. Among 16 studied cases, 14 cases showed normal karyotype (nine with 46, XY; five with 46, XX). One case showed trisomy 16(47, XY, + 16) and another showed variation from normal chromosomal complement (46, XY, 14s+), resulting in 6.3% incidence of the structural abnormalities of the chromosome. On the basis of our study, we determined the possibility of chorionic villi karyotyping in ectopic pregnancy. This ectopic conceptuses are no more likely to show chromosomal abnormalities than in utero conceptuses of comparable gestational age. Therefore, maternal factors such as salpingitis and peritubal adhesion are the most likely explanations for ectopic pregnancy.

Bridging the gap between laboratory and clinic in child and adolescent psychotherapy

Meta-analyses of laboratory outcome studies reveal beneficial effects of psychotherapy with children and adolescents. However, the research therapy in most of those lab studies differs from everyday clinic therapy in several ways, and the 9 studies of clinic therapy the authors have found show markedly poorer outcomes than research therapy studies. These findings suggest a need to bridge the long-standing gap between outcome researchers and clinicians. Three kinds of bridging research are proposed and illustrated: (a) enriching the research data base on treatment effects by practitioners in clinical settings--including private practice and health maintenance organizations, (b) identifying features of research therapy that account for positive outcomes and applying those features to clinical practice, and (c) exporting lab-tested treatments to clinics and assessing their effects with referred youths. If these bridging strategies were widely adopted, despite the numerous obstacles described herein, real progress might be made toward more effective treatment in clinical practice.

Inhibitory effects of H2-receptor antagonists on cytochrome P450 in male ICR mice

1. The present study was undertaken to examine the effects of H2-receptor antagonists including newly developed mifentidine derivatives, IY-80843 and IY-80845, on cytochrome P450(P450) in vitro and in vivo. 2. Initially, 3-methylcholanthrene-, phenobarbital-, ethanol- and dexamethasone-induced liver microsomes were prepared from male ICR mice to study in vitro effects of above chemicals on ethoxyresorufin O-deethylase(EROD), pentoxyresorufin O-dealkylase(PROD), p-nitrophenol hydroxylase and erythromycin N-demethylase(ERDM) activities, respectively. It was found that histamine, cimetidine and famotidine were not inhibitory to four enzyme activities. Meanwhile, mifentidine slightly inhibited EROD and PROD activities and its derivatives IY-80843 and IY-80845 strongly inhibited PROD, EROD and ERDM activities. 3. Prolongation of hexobarbital-induced sleeping time was determined in male ICR mice to confirm in vitro inhibitory effects of mifentidine and its derivatives in vivo. It was observed that cimetidine, mifentidine, IY-80843 and IY-80845 caused dose-dependent increases in the sleeping time, indicating the inhibition of P450 responsible for hexobarbital metabolism. 4. It was concluded that mifentidine and its derivatives are P450 inhibitors and that our newly synthesized IY-80843 is most inhibitory. 5. The present results indicate that mifentidine and its derivatives not only antagonise the H2-receptor but also inhibit P450 enzymes.

Effects of psychotherapy with children and adolescents revisited: a meta-analysis of treatment outcome studies

A meta-analysis of child and adolescent psychotherapy outcome research tested previous findings using a new sample of 150 outcome studies and weighted least squares methods. The overall mean effect of therapy was positive and highly significant. Effects were more positive for behavioral than for nonbehavioral treatments, and samples of adolescent girls showed better outcomes than other Age x Gender groups. Paraprofessionals produced larger overall treatment effects than professional therapists or students, but professionals produced larger effects than paraprofessionals in treating overcontrolled problems (e.g., anxiety and depression). Results supported the specificity of treatment effects: Outcomes were stronger for the particular problems targeted in treatment than for problems not targeted. The findings shed new light on previous results and raise significant issues for future study.

Pharmacokinetics of theophylline: effects of hepatic fibrosis in rats induced bile duct ligation

This experiment was performed to evaluate the usefulness of an experimental fibrosis model by bile duct ligation as a pharmacokinetic model of a disease state. First, experimental liver fibrosis was produced by bile duct ligation. At 4 weeks postoperation, a fibrotic condition was characterized by measurement of the aminoterminal procollagen type III peptide (PIIINP) level in serum, total collagen content in liver and light microscopic histology. Four weeks after bile duct ligation there was an increase in total collagen content of the liver to 430% of the initial values, accompanied by an increase of serum-PIIINP (385%). Secondly, we examined the pharmacokinetics of theophylline in the fibrotic rat induced by bile duct ligation. An i.v. dose of 8 mg of theophylline per kg of body weight was administered, and the levels of theophylline in serum were assayed by high performance liquid chromatography. The area under the serum concentration-time curve of theophylline was increased significantly in fibrotic rats compared with that of the control, and the total clearance of drug in fibrotic rats was low, averaging 22.6 mg/kg/h vs. 36.1 and 60.9 ml/kg/h in the control and the normal rat, respectively. However, the value of distribution during the beta-phase was not significantly affected by experimental liver fibrosis.