[The potential role of growth factor in the airway wall remodeling of a chronic obstructive pulmonary disease rat model and the effects of drugs on them]

OBJECTIVE

To evaluate the expression and distribution of transforming growth factor-beta1 (TGF-beta1), epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) in the lung tissue of chronic obstructive pulmonary (COPD) rat models and the relationship between these growth factors and the airway wall remodeling. The effects of drugs on them were also investigated.

METHODS

The COPD rat model (model group) was established by intratracheal instillation of lipopolysaccharide twice and daily exposure to cigarette smoking. Drug intervention groups received daily inhalation of heparin since the second week and TGF-beta1 monoclonal antibody (TB21) 0.5 mg twice through the tail veins. At the end of four weeks, the thickness of the smooth muscle and collagen in bronchi and pulmonary arterioles were measured by computer image analyzer, also the protein and gene relative content of these growth factors as well as the effects of drugs on them were observed.

RESULTS

There was a significant increase in the smooth muscle and collagen thickness in the bronchi and pulmonary arterioles of the model group in comparison with that of the control group (P < 0.01), the relative contents for TGF-beta1, EGF and bFGF in the epithelial cells of the bronchi, endothelial cells of the pulmonary arterioles and alveolar macrophages of the model group were significantly higher than those of control group (P < 0.001 approximately 0.05). The relative content for TGF-beta1 in TB21 group was significantly lower than that of model group (P < 0.01). These were statistical positive relationships between the smooth muscle e thickness of bronchi and the relative contents for TGF-beta1, EGF and bFGF in the epithelial cells, between the collagen thickness of the bronchi and the relative content for TGF-beta1, between the smooth muscle thickness of the pulmonary arterioles and the relative content for TGF-beta1 and EGF in the endothelial cells (P < 0.05 approximately 0.01).

CONCLUSION

TGF-beta1, EGF and bFGF may play an important role in the airway wall and pulmonary arteriole structure remodeling in COPD, the intervention against TGF-beta1 and long term inhalation of heparin mat be helpful for the inhibition of airway wall remodeling in human COPD and worth of further observation.

High-level dietary vitamin A enhances T-helper type 2 cytokine production and secretory immunoglobulin A response to influenza A virus infection in BALB/c mice

Vitamin A supplementation during acute pneumonia has not improved recovery in most human clinical trials. We hypothesize that high vitamin A intake may decrease the production of T-helper type-1 (Th1) cytokines and thereby inhibit antiviral responses. Such decreases might impair recovery from viral respiratory infections. We thus examined the effect of three interventions on viral pneumonia: 1) a high level vitamin A [250,000 IU/kg diet or 75,000 retinol equivalents (RE)/kg], or 2) control diet (4000 IU/kg diet or 1200 RE/kg) given before and during infection, and 3) initiating the high level diet upon infection to simulate the adjuvant therapy used in clinical trials. No difference was seen among the interventions in severity of disease (weight loss, lung virus titers and survival). However, both the high level diet group and the group in which vitamin A was increased at the time of infection had greater salivary immunoglobulin (Ig)A responses (geometric means, 166 and 105 microg/L, respectively) than did the control group (59 microg/L) (P = 0.0019). In contrast, the serum IgG response was higher in the control group (324+/-158 mg/L) than in the high level group (225+/-95 mg/L) (P = 0.028), although it did not differ from the group in which the diet was changed upon infection (230+/-163 mg/L) (P = 0.084). The production of interferon-gamma (IFN-gamma), a Th1 cytokine, was lower in the high level diet group (median, 0.153 microg/L) compared with the control group (median, 0.839 microg/L) (P = 0.014), whereas the production of interleukin-10 (IL-10), a Th2 cytokine, was higher with the high level diet (median, 0.304 microg/L) than with the control (median, 0.126 microg/L) (P = 0.022). This change in the Th1/Th2 pattern was not sufficient to affect recovery from viral pneumonia but may account for the increased IgA and decreased IgG responses seen with high level dietary vitamin A in this study. These data reinforce the lack of utility of vitamin A in treating acute pneumonia in children and suggest that high dose vitamin A supplements may enhance Th2-mediated immune responses, which are particularly beneficial in the case of extracellular bacterial and parasitic infections and IgA-mediated responses to mucosal infections.

A clinical study of yi zhi capsules in prevention of vascular dementia

The raised score in the revised Hasegawa dementia scales (HDS) demonstrated that the effect of Yi Zhi Capsules (YZC) in treating loss of intellectual function after cerebrovascular diseases was significantly better than that of the western drug Piracetam [symbol: see text] (P < 0.01). The morbidity of vascular dementia was much lower in the treatment group than that of the control group (P < 0.05) after a one-year follow-up; and the blood lipid level and some indexes in rheological examinations were also improved significantly (P < 0.05, or < 0.01). The data indicate that YZC is a relatively good preparation for prevention of vascular dementia.

Determination of the site of glucuronidation in an N-(3,5-dichlorophenyl)succinimide metabolite by electrospray ionization tandem mass spectrometry following derivatization to picolinyl esters

Derivatization using 3-pyridylcarbinol coupled with liquid chromatography electrospray ionization tandem mass spectrometry (LC/MS/MS) was used to characterize a novel Phase II metabolite of the nephrotoxic agricultural fungicide, N-(3,5-dichlorophenyl)succinimide (NDPS). A glucuronide conjugate of N-(3,5-dichlorophenyl)-2-hydroxysuccinamic acid (2-NDHSA) was identified in the urine from a rat dosed with [14C]NDPS. However, 2-NDHSA contains an aliphatic hydroxyl group and a carboxylic acid group, both of which are potential sites for glucuronidation. Mass spectrometry alone was unable to distinguish between these possibilities. Since the position of glucuronidation may be important in the mechanism of NDPS-induced nephrotoxicity, chemical derivatization in conjunction with mass spectrometry was used to characterize the glucuronide. The 2-NDHSA glucuronide conjugate was isolated from rat urine, derivatized with 3-pyridylcarbinol, and the derivatized metabolite was then analyzed by LC/MS/MS. Two known NDPS metabolites, 2-NDHSA and N-(3,5-dichlorophenyl)succinamic acid (NDPSA), were also isolated from rat urine and derivatized similarly. 3-Pyridinylcarbinol reacted rapidly with the carboxylic acid groups and formation of the picolinyl esters increased the ionization potential under positive ion conditions. The urinary glucuronide of 2-NDHSA was identified as an alcohol-linked glucuronide by examination of the molecular ions and the collision-induced dissociation (CID) product ion spectra of the derivatized products. When used in combination with mass spectrometry, derivatization of carboxylic acids with 3-pyridylcarbinol provided useful mass fragmentations and is a rapid way to obtain structural information about the position of glucuronidation of NDPS metabolites.

Identification of the major human liver cytochrome P450 isoform(s) responsible for the formation of the primary metabolites of ziprasidone and prediction of possible drug interactions

AIMS

To identify the cytochrome P450 (CYP) isoform(s) responsible for the formation of the primary metabolite of ziprasidone (ziprasidone sulphoxide), to determine the kinetics of its formation and to predict possible drug interactions by investigating CYP isoform inhibition in an in vitro study.

METHODS

In vitro metabolism of [14C]-ziprasidone was studied using human liver microsomes. The metabolites were identified using mass spectrometry. The kinetics of metabolite formation were determined using [14C]-ziprasidone (10-200 microM) over 5 min, and Km and Vmax were estimated from Lineweaver-Burk plots. IC50 values for the inhibition of specific probe substrates for CYP1A2, CYP2C9, CYP2C19, CYP2D6 and CYP3A4, by ziprasidone, risperidone and 9-hydroxyrisperidone were also determined using human liver microsomes from three subjects. Mean Ki values were calculated.

RESULTS

Three CYP-mediated metabolites - ziprasidone sulphoxide, ziprasidone sulphone and oxindole acetic acid - were identified. The apparent Km and Vmax values for the formation of the major metabolite, ziprasidone sulphoxide (measured as the sum of sulphoxide and sulphone) were 235 microM and 1.14 nmol mg(-1) protein min(-1), respectively. Isoform-selective inhibitors and recombinant enzymes indicated that CYP3A4 is responsible for the formation of ziprasidone metabolites. Ziprasidone was not a substrate for the other isoforms studied. Similar in vitro inhibition of CYP2D6 (Ki 6.9-16 microM) and CYP3A4 (Ki 64-80 microM) was obtained with ziprasidone, risperidone and 9-hydroxyrisperidone. The in vivo free drug concentrations associated with clinically effective doses of ziprasidone are at least 1500-fold lower than the mean Ki for either CYP2D6 inhibition or CYP3A4 inhibition.

CONCLUSIONS

Ziprasidone is predominantly metabolized by CYP3A4 in human liver microsomes and is not expected to mediate drug interactions with coadministered CYP substrates, at clinically effective doses.

In vitro and in vivo studies on the metabolism of tirofiban

Tirofiban hydrochloride [L-tyrosine-N-(butylsulfonyl)-O-[4-(4-piperidinebutyl)] monohydrochloride, is a potent and specific fibrinogen receptor antagonist. Radiolabeled tirofiban was synthesized with either (3)H-label incorporated into the phenyl ring of the tyrosinyl residue or (14)C-label in the butane sulfonyl moiety. Neither human liver microsomes nor liver slices metabolized [(14)C]tirofiban. However, male rat liver microsomes converted a limited amount of the substrate to a more polar metabolite (I) and a relatively less polar metabolite (II). The formation of I was sex dependent and resulted from an O-dealkylation reaction catalyzed by CYP3A2. Metabolite II was identified as a 2-piperidone analog of tirofiban. There was no evidence for Phase II biotransformation of tirofiban by microsomes fortified with uridine-5'-diphospho-alpha-D-glucuronic acid. After a 1 mg/kg i.v. dose of [(14)C]tirofiban, recoveries of radioactivity in rat urine and bile were 23 and 73%, respectively. Metabolite I and unchanged tirofiban represented 70 and 30% of the urinary radioactivity, respectively. Tirofiban represented >90% of the biliary radioactivity. At least three minor biliary metabolites represented the remainder of the radioactivity. One of them was identified as I. Another was identified as II. When dogs received 1 mg/kg i.v. of [(3)H]tirofiban, most of the radioactivity was recovered in the feces as unchanged tirofiban. The plasma half-life of tirofiban was short in both rats and dogs, and tirofiban was not concentrated in tissues other than those of the vasculature and excretory organs.

[A study on tumor necrosis factor alpha, macrophage inflammatory protein-2 and myeloperoxidase in blood, broncho-alveolar fluid and lung tissues of rat chronic bronchitis model]

OBJECTIVE

To study the nature and mechanisms of airway inflammation in chronic bronchitis and observe the effects of inhaled glucocorticoids on inflammatory indices.

METHODS

Rat chronic bronchitis model was established by intratracheal instillation of small dose of lipopolysaccharide (LPS, 1 g/L). Experiments were performed in 28 male Sprague-Dawley rats, which comprised four groups in random, i.e. chronic bronchitis model group, normal saline treated group, dexamethasone treated group and healthy control group. The levels of myeloperoxidase (MPO) of blood and lung tissues, and tumor necrosis factor (TNF)alpha and macrophage inflammatory protein-2 (MIP-2) of plasma, broncho-alveolar fluid (BALF) and lung tissues were determined by biochemical and ELISA methods. Total and differential white blood cell counts of BALFwere carried out.

RESULTS

(1) The levels of TNFalpha and MIP-2 in BALF and lung tissues, and MPO in lung tissues of chronic bronchitis model group were significantly increased than those of control group (P < 0.05). (2) More significant increase in total white blood cell count and neutrophils in BALF was found in rat chronic bronchitis group than in control group (P < 0.001). (3) Significant positive correlations were observed between the level of MPO and MIP-2 of lung tissues, the level of MPO and TNFalpha of lung tissue and the total cell counts and the level of MIP-2 of BALF and lung tissue. (4) More significant decrease in total cell counts and neutrophils of BALF and levels of MPO in lung tissue was found in dexamethasone-treated group as compared to those of chronic bronchitis group.

CONCLUSION

Recruitment and activation of neutrophils seem to be the characteristics of chronic bronchitis. TNFalpha and MIP-2 may be involved in the process of chemotaxis and activation in airway inflammation in chronic bronchitis. Inhaled steroids might have some effects on chronic bronchitis by limiting the airway inflammation.

[Transfection of articular chondrocytes with PcNDA3-hBMP3 and its stable expression]

OBJECTIVE

To explore the possibility of stable expression of PcDNA3-hBMP3 in cultured articular chondrocytes of rabbit.

METHODS

PcDNA3-hBMP3 was constructed using gene clone technique and recombined DNA technique. With the help of profectamine, the cultured articular chondrocytes were transfected with PcDNA3-hBMP3, and the evidence of successfully stable transfection in these cells could be obtained by positive northern blot.

RESULTS

The cultured articular chondrocytes of rabbits seemed to be polygonal, and its logarithmic growth phase was 2 - 4 days after cell inoculation. The two fragments cut from PcDNA3-hBMP3 by EcoR I and Xba I represented 5.4 kb and 1.4 kb by electrophoresis, which were confirmed to be the carrier and the fragment inserted originally, indicating that the construction of PcDNA3-hBMP3 was successful. The RNA extracted from cultured chondrocytes was screened for 4 weeks by G418 hibrided with the fragment cut from hBMP3 positively.

CONCLUSIONS

With the help of profectamine, the cultured articular chondrocytes can be transfected by recombined gene of PcDNA3-hBMP3 successfully, and their stable expression at 4 weeks after transfection is obtained.

Subcellular distribution and tissue expression of phospholipase Dalpha, Dbeta, and Dgamma in Arabidopsis

Three phospholipase Ds (PLDs; EC 3.1.4.4) have been cloned from Arabidopsis, and they exhibit two distinct types of activities: polyphosphoinositide-requiring PLDbeta and PLDgamma, and polyphosphoinositide-independent PLDalpha. In subcellular fractions of Arabidopsis leaves, PLDalpha and PLDgamma were both present in the plasma membrane, intracellular membranes, mitochondria, and clathrin-coated vesicles, but their relative levels differed in these fractions. In addition, PLDgamma was detected in the nuclear fraction. In contrast, PLDbeta was not detectable in any of the subcellular fractions. PLDalpha activity was higher in the metabolically more active organs such as flowers, siliques, and roots than in dry seeds and mature leaves, whereas the polyphosphoinositide-dependent PLD activity was greater in older, senescing leaves than in other organs. PLDbeta mRNA accumulated at a lower level than the PLDalpha and PLDgamma transcripts in most organs, and the expression pattern of the PLDbeta mRNA also differed from that of PLDalpha and PLDgamma in different organs. Collectively, these data demonstrated that PLDalpha, PLDbeta, and PLDgamma have different patterns of subcellular distribution and tissue expression in Arabidopsis. The present study also provides evidence for the presence of an additional PLD that is structurally more closely related to PLDgamma than to the other two PLDs.

Identification of in vitro metabolites of Indinavir by "intelligent automated LC-MS/MS" (INTAMS) utilizing triple quadrupole tandem mass spectrometry

In an effort to improve the efficiency of the TSQ 7000 LC-MS/MS system for identification of drug metabolites in biological matrices in support of drug discovery programs, a combination of instrument control language procedures for the Finnigan MAT TSQ 7000 mass spectrometer, referred to as INTAMS, were composed. INTAMS was designed to conduct unattended, automatic liquid chromatography/mass spectrometry (LC-MS) and LC-MS/MS analyses of drugs and metabolites in commonly encountered in vitro biological matrices. A novel peak detection algorithm was developed to automatically detect and record the pseudomolecular ions and retention times of chromatographic components, even if not fully resolved. This algorithm was used in combination with an automated technique for predicting the molecular weights of metabolites based on incremental changes of the molecular weight of the parent drug resulting from well-known biotransformation processes. When applied to a sample of an incubation mixture of the HIV protease inhibitor Indinavir with a rat liver S9 preparation, the results obtained by the automatic metabolite detection procedures for LC-MS and LC-MS/MS analyses in real time were the same as those which were determined manually, by a knowledgeable operator.

[The clinical diagnostic significance on detection of Mycoplasma pneumoniae antigen in upper respiratory tract epithelium]

OBJECTIVE

To investigate the early diagnosis of pulmonary mycoplasma pneumoniae (MP) infection by detection of MP antigen in upper respiratory tract epithelium.

METHOD

A prospective study on respiratory MP infection was conducted in 110 patients with acute respiratory infection from February 1996 to November 1997 in our hospital. Upper respiratory tract epithelia were collected from gargle and MP antigen was detected by immunofluorescent assay (IFA). At the same time, serum samples were taken and immunoglobulin M (IgM) fractions of specific antibody to MP were assessed by the same method in 70 of 110 patients. Moreover, clinical features, cold agglutination test and chest X-ray were also collected for analysis.

RESULT

The positive rates of MP antigens and IgM antibody were 17% and 20%, respectively, while the titer on cold agglutination test > 1:8 in only two patients. The clinical features in patients with positive MP antigen and/or IgM antibody were similar to that of pulmonary MP infection.

CONCLUSION

Examination of MP antigen in upper respiratory tract epithelium collected from gargle combined with serum specific IgM antibody is a good method for the early diagnosis of pulmonary MP infection.

Solution structure of N-terminal segment of hepatitis B virus surface antigen Pre-S1

A synthetic peptide, the N-terminus of hepatitis B virus surface antigen Pre-S1, was studied by two-dimensional NMR techniques. A series of(1)H nuclear magnetic resonance experiments were used to complete the identification of spin systems and sequential assignments of this 28-residue peptide. 157 distance constraints and 55 dihedral angle constraints were obtained. 20 structures with the lowest target function were selected by the distance geometry program DIANA. Energy minimization and the following 100 ps time-averaged restrained molecular dynamics (TR-MD) simulation in aqueous solution were performed for each conformer. After TRMD simulation, three locally convergent regions corresponding to residues 22-31, 36-40, 41-46 were found. The averaged pairwise root-mean-square deviation (RMSD) of backbone atoms for them were (1.71+/-0.49)A, (0.76 +/-0.31)A, (1.05 +/- 0.52)A, respectively. Four reverse turns found in these regions, residues 22-25, 37-40, 41-44 and 43-46, correspond to several important antibody binding sites revealed in relevant immunological research.

Metabolism and excretion of a new anxiolytic drug candidate, CP-93, 393, in healthy male volunteers

CP-93,393 [(7S,9aS)-1-(2-pyrimidin-2-yloctahydropyrido[1,2-a] pyrazin-7-ylmethyl)pyrrolidine-2,5-dione] is a new anxiolytic drug with highly selective serotonin 5-hydroxytryptamine 1A autoreceptor agonist, alpha2-adrenergic antagonist, and dopamine D2 agonist properties. The excretion, biotransformation, and pharmacokinetics of CP-93,393 were investigated in six healthy male volunteers after oral administration of a 5-mg dose of [14C]CP-93,393. The administered radioactivity was excreted predominantly in the urine. One week after administration of the dose, cumulative excretion amounted to 67.8 +/- 2.5% in the urine and 22.0 +/- 5.6% in the feces. In total, 89.8 +/- 5.7% of the radioactive dose was recovered in urine and feces. Mean maximum plasma concentration values for unchanged CP-93,393 were 10.92 and 1.02 ng/ml for poor metabolizers (PMs) and extensive metabolizers (EMs) of dextromethorphan, respectively. AUC0-infinity values for unchanged CP-93,393 were also greater for PMs than for EMs, whereas the mean maximum plasma concentration and AUC0-infinity values for total radioactivity were similar for the two phenotypes. Less than 0.5% of the dose was excreted in urine as unchanged drug for both EMs and PMs, suggesting extensive metabolism of CP-93,393 in both phenotypes. Hydroxylation at the 5-position of the pyrimidine ring was identified as the main metabolic pathway. 5-Hydroxy-CP-93,393 (M-15) and its glucuronide and sulfate conjugates (M-7 and M-13, respectively) accounted for approximately 51% of the administered dose in excreta of both PMs and EMs. Hydrolysis of the succinimide ring, in combination with 5-hydroxylation and/or conjugation or not, accounted for approximately 9% of the dose. A novel metabolite, apparently resulting from oxidative degradation of the pyrimidine ring, was characterized as the amidine analog M-18. M-15 (47-62%), its sulfate conjugate (M-13, approximately 9%), and the pyrimidine ring-cleaved product (M-18, 7-13%) were identified as the major circulating metabolites for both EMs and PMs. Therefore, CP-93,393 undergoes metabolism by three primary pathways, i.e. 1) aromatic hydroxylation followed by conjugation with glucuronic acid and sulfuric acid, 2) oxidative degradation of the pyrimidine ring, and 3) hydrolysis of the succinimide ring. The identified metabolites accounted for approximately 90, 91, and 92% of the total radioactivity present in urine, plasma, and feces, respectively. The major in vivo oxidative metabolites were also observed after in vitro incubations with human liver microsomes.

[Detection of ET-1, TNF-alpha, oxidative radicals in sera of asthmatics and in sera and lung tissue of asthmatic guinea pigs]

OBJECTIVE

To investigate the role of the ET-1, TNF-alpha and oxidative radicals of MDA and SOD in the pathogenesis of asthma and the effect of the nitric oxide synthase inhibitor, L-NAME to above factors.

METHOD

ET-1 was detected by the radio-immunoassay and TNF-alpha was detected by ELISA, SOD and MDA were detected by using thiobarbituric acid method.

RESULT

The contents of ET-1, TNF(and MDA in the serum of the asthmatic patients and in the serum and lung tissue of asthma models of guinea pigs were significantly increased, in the contrast, the content of SOD was decreased compared with those in the controls(P < 0.01). All the changes in the serum and in the lung tissues of the asthma models of guinea pigs returned to the levels of the controls by dexamethasone inhalation or L-NAME by intraperitoneal injection.

CONCLUSION

ET-1, TNF alpha and the oxidative radicals and NO may play important roles in the pathogenesis of asthma, L-NAME, which is similar to the dexathamethsone, may either decrease the content of NO or decrease the content of ET-1, TNF alpha and oxidative radicals in asthma.

An immunohistochemical study of amyloid P component, apolipoprotein E and ubiquitin in human and murine amyloidoses

Amyloid P component (AP) and apolipoprotein E (Apo E), which are known to be minor constituents of amyloid deposits, commonly are associated with almost all types of amyloid deposits. In this study, the distribution of AP-, Apo E- and ubiquitin (Ub)-immunoreactivity (IR) in amyloid deposits in the liver and spleen of human systemic amyloidosis (34 autopsy cases: 17 immunoglobulin light chain derived, 17 amyloid A protein derived) and experimental murine amyloidosis is examined using an immuno-histochemical technique. In human cases, all of the amyloid deposits examined showed colocalization of AP- and Apo E-IR with individual amyloid proteins. In experimental amyloidosis, AP-IR of amyloid deposits in the liver and spleen and Apo E-IR in the liver were seen uniformly throughout this experiment. In contrast, Apo E-IR in the spleen was not uniform at the phase of amyloid deposition. At 4 weeks and at 16 weeks after casein injection, Apo E-IR was unevenly distributed in amyloid deposits in the perifollicular area; however, from 6 to 12 weeks it was seen to be uniform. Ubiquitin-IR of amyloid deposits in human cases was seen in 22 of 34 livers and in 22 of 33 spleens. In experimental amyloidosis, Ub-IR of amyloid deposits was demonstrated in the space of Disse in all mice examined, and there appeared to be a gradual increase in intensity with the amount of amyloid deposition. However, in the spleen, amyloid deposits did not react with anti-Ub antibody in any phase of amyloid induction. These results suggest that Apo E and Ub are not always associated with the process of amyloid deposition and may appear in a deposit after the deposition.

Identification of drug metabolites in biological matrices by intelligent automated liquid chromatography/tandem mass spectrometry

A rapid and systematic strategy for the identification of drug metabolites in biological matrices based on liquid chromatography-tandem mass spectrometry (LC/MS/MS) techniques was utilized for the identification of drug metabolites of the HIV protease inhibitor Indinavir. This strategy integrates intelligent realtime mass spectrometry with HPLC detection and a predictive strategy for detecting metabolites arising from common biotransformations, to rapidly elucidate structures of drug metabolites. Structures of metabolites generated from in vitro incubation mixtures of Indinavir were characterized from a single chromatographic analysis using the automated LC/MS/MS methodology, thus reducing data acquisition time and improving efficiency.

Metabolism and excretion of a new antianxiety drug candidate, CP-93,393, in cynomolgus monkeys: identification of the novel pyrimidine ring cleaved metabolites

The metabolism and excretion of a new anxiolytic/antidepressant drug candidate, CP-93,393, ((7S, 9aS)-1-(2-pyrimidin-2-yl-octahydro-pyrido[1, 2-a]-pyrazin-7-yl-methyl)-pyrrolidine-2,5-dione) were investigated in cynomolgus monkeys after oral administration of a single 5 mg/kg dose of 14C-CP-93,393. Urine, bile, feces, and blood samples were collected and assayed for total radioactivity, parent drug, and metabolites. Total recovery of the administered dose after 6 days was 80% with the majority recovered during the first 48 hr. An average of 69% of the total radioactivity was recovered in urine, 4% in bile, and 7% in feces. Mean Cmax and AUC(0-infinity) values for the unchanged CP-93,393 were 143.2 ng/ml and 497.7 ng.hr/ml, respectively, in the male monkeys and 17.2 ng/ml and 13.7 ng.hr/ml, respectively, in the female monkeys. HPLC analysis of urine, bile, feces, and plasma from both male and female monkeys indicated extensive metabolism of CP-93,393 to several metabolites. The identification of metabolites was achieved by chemical derivatization, beta-glucuronidase/sulfatase treatment, and by LC/MS/MS, and the quantity of each metabolite was determined by radioactivity detector. CP-93,393 undergoes metabolism by three primary pathways, aromatic hydroxylation, oxidative degradation of the pyrimidine ring, and hydrolysis of the succinimide ring followed by a variety of secondary pathways, such as oxidation, methylation, and conjugation with glucuronic acid and sulfuric acid. The major metabolites, oxidation on the pyrimidine ring to form 5-OH-CP-93,393 (M15) followed by glucuronide and sulfate conjugation (M7 and M13), accounted for 35-45% of the dose in excreta. Two metabolites (M25 and M26) were formed by further oxidation of M15 followed by methylation of the resulting catechol intermediate presumably by catechol-O-methyl transferase. A novel metabolic pathway, resulting in the cleavage of the pyrimidine ring, was also identified. The metabolites (M18, M20, and M21) observed from this pathway accounted for 8-15% of the dose. Aliphatic hydroxylation of the succinimide ring was a very minor pathway in monkey. 5-Hydroxy-CP-93,393 (M15, 37-49%), its sulfate and glucuronide conjugates (M7 and M13, approximately 34%), and the pyrimidine ring cleaved product (M18, approximately 8%) were the major metabolites in monkey plasma. The identified metabolites accounted for approximately 90, 93, 97, and 92% of the total radioactivity present in urine, bile, plasma, and feces, respectively. The major in vivo oxidative metabolites were also observed after in vitro incubations with monkey liver microsomes.

Amyloid A protein amyloidosis induced in apolipoprotein-E-deficient mice

Apolipoprotein E (apoE) is a constituent of lipoproteins other than low-density lipoprotein, and it principally acts in the transport and metabolism of plasma cholesterol and triglyceride. ApoE is a minor constituent of various kinds of amyloidoses and may play a role as a pathological chaperone for fibrillogenesis of amyloid fibril protein with the amyloid P component and proteoglycans. In this study, we examined the role of apoE in amyloidogenesis in vivo in apoE-deficient mutant mice with amyloid A protein (AA) amyloidosis induced by inflammatory stimulation. Amyloid deposition was seen in six of nine C57BL/6J control mice and in six of eight apoE-deficient mutant mice after the intraperitoneal and subcutaneous injections of the mixture of complete Freund's adjuvant and Mycobacterium butyricum. Moreover, amyloid deposition in apoE-deficient mice as well as C57BL/6J control mice started 48 or 72 hours after injection of amyloid-enhancing factor and silver nitrate, although the amount of amyloid deposit in C57BL/6J control mice was slightly larger than that in apoE-deficient mice. These amyloid deposits reacted with anti-mouse AA antibody were seen in the perifollicular area of the spleen. Immunoreactivity of apoE was seen irregularly in the amyloid deposits of C57BL/6J control mice but not in the amyloid deposit of apoE-deficient mice. From these results, we concluded that apoE is not always necessary for amyloid deposition and that the existence of apoE might slightly accelerate AA amyloid deposition in the earliest phase of AA amyloid deposition.

[Chemical constituents of Bulgaria inquinans (Fries)]

Three compounds were isolated from Bulgaria inquinans. They were identified as ergosterol, galacitiol and ethanedioic acid.

Characterization of the novel benzisothiazole ring-cleaved products of the antipsychotic drug ziprasidone

Characterization of two novel benzisothiazole ring cleaved metabolites of the antipsychotic drug, ziprasidone (ZIP), in rat has been described. Metabolites designated M6 and M9 were isolated from urine and bile of the rat dosed with radiolabeled ZIP and purified by reversed phase HPLC. The chemical structures of these metabolites were assigned based on tandem mass spectrometry in combination with chemical derivatization techniques. M6 and M9 were unaffected upon treatment with N-(tert-butyldimethylsilyl)-N-methyltrifluoroacetamide. Reaction of M9 with aqueous TiCl3 also did not change the HPLC retention time or the CID spectrum of metabolite M9. These data excluded the possibility that these metabolites were owing to N-oxidation and/or aromatic hydroxylation. M6 and M9 were generated only when in vitro incubations of ZIP were conducted with human liver S-9 fraction in the presence of S-adenosyl-L-methionine. Based on these data, metabolites M6 and M9 were identified as S-methyl-dihydro-ZIP and S-methyl-dihylro-ZIP-sulfoxide, respectively. The structure of M9 was unambiguously confirmed by comparing the LC/MS retention time and mass spectral data with synthetic standard. A mechanism for the formation of these metabolites from ZIP is proposed.

[The role of nitric oxide in the pathogenesis of asthma]

OBJECTIVE

To investigate the role of nitric oxide (NO) in the pathogenesis of asthma, we observed the influence of L-NG-arginine-methylester (L-NAME), the inhibitor of nitric oxide synthase (NOS), on the contraction of isolated guinea pig tracheal smooth muscles and observed the changes of NOS in the guinea pig asthma model lung tissues using histochemical detection.

METHODS

Male Hartley guinea pig isolated tracheal ring were incubated with L-NAME 2.0 mmol/L for 30 min and histamine was given to make a concentration response curve. The sections of guinea pig asthma model lung tissues were stained with NADPH diaphorase.

RESULTS

The histamine concentration response curve was significantly shifted upward in the L-NAME incubated group, the maximal response increased by 170% compared with that of control group. The numbers of alveolar macrophages were significantly increased and NADPH diaphorase staining was positive in asthma model group, in contrast, the alveolar macrophages were hardly seen and there was almost no positive staining of NOS in the control group.

CONCLUSIONS

The inhibition of NO synthesis of guinea pig respiratory tract with L-NAME results in a marked increase in airway contraction in vitro after histamine provocation. This result indicate that NO has relaxant effect on tracheal smooth muscles and may decrease airway responsiveness to histamine. The increased alveolar macrophages and positive stained NOS in the lung tissues of asthma model indicate that NO, which is synthesized by the NOS in alveolar macrophages, may play an important role in asthma pathogenesis.

[Clinical significance of beta 2-microglobulin content in nasopharyngeal secretion]

To study its clinical significance, beta 2-microglobulin (beta 2-MG) in nasopharyngeal secretion was examined using radioimmunoassasy methods in 73 patients with nasopharyngeal carcinoma (NPC), 30 with chronic nasopharyngitis and 30 normal control subjects. In 31 NPC patients, the examination was repeated before and after radiotherapy. The average concentrations of beta 2-MG were 4.87 +/- 2.51 mg/L in NPC group, 1.05 +/- 0.64 mg/L in chronic nasopharygitis group, and 0.85 +/- 0.32 mg/L in the control. The beta 2-MG concentration was higher in the NPC patients than in both chronic pharyngitis patients and normal subjects (P < 0.01). The concentration was lowered down in NPC patients after radiotherapy, and remained high when the treatment failed to control the condition. It seems that beta 2-MG level in nasopharyngeal secretion is closely related to the prognosis and recurrence of nasopharyngeal carcinoma.

[Physiological effects of cabin temperature decrease on human]

To study effects of cabin temperature on human body, changes in rectal temperature, local skin temperature, local skin heat fluxes and skin infrared thermogram were observed in 5 male subjects dressed in different thermal insulation clothings under 20 degrees C, 15 degrees C and 10 degrees C cabin temperatures. The results showed that, average skin temperature and tip temperature obviously dropped, and skin heat fluxes increased with falling of cabin temperature, and changes of local skin infrared thermogram were significant. Subjective feeling were comfortable and cool at cabin temperature of 20 degrees C and 15 degrees C respectively. While subjective feeling was cold and there was a thermal debt of body 144 kJ/m2 at 10 degrees C which indicated that it was slightly cold but tolerable. The results may be valuable in determining the lowest tolerable limit of cabin temperature.

Fluorescence studies on the interaction of a synthetic signal peptide and its analog with liposomes

The N-terminal signal sequence of glucitol permease of Escherichia coli (Gut22: MIETITPGAVWFIGLFQKGGEC) and its analog (Gut22Ana: MIETITHGAEWFIGLFQKGGEC) were synthesized. The analog had a Pro residue substituted for the His at the 7th position of Gut22 and a Val residue substituted for the Glu at the 10th position. Previous studies indicated that due to its structural rigidity, the interaction of Gut22Ana with lipid bilayer was much weaker than that of Gut22 (Wang, Q.D., Cui, D.F. and Lin, Q.S. (1996) Science in China (Series C) 39, 395-405). To further probe the location of the tryptophan residues of the peptides in lipid bilayer, the membrane penetration depth of the tryptophan residue of Gut22 was measured using spin-labeled phospholipids, and fluorescence quenching of the peptides by iodide and acrylamide in the presence and absence of phosphatidylserine/phosphatidylcholine liposomes were also studied. Fluorescent labeling of the peptides enabled the study of their association with membrane by fluorospectrophotometry. In the presence of liposomes, the peptides were protected from reaction with chymotrypsin, indicating that the peptide incorporated into the membrane. However, dithionite, which acts external to the membrane, reacted with the peptide, showing that the peptides did not translocate across lipid bilayer spontaneously.

Organic vapor sensors based on SAW resonator and organic films

The majority of investigations of SAW devices used as chemical sensors are based on delay line oscillators. However, SAW resonator oscillator offers some advantages over the SAW delay line oscillator for its higher stability. In the incipient stage of fabricating gas sensors based upon SAW resonator, taking detection of organic vapor as an example, the analysis method that combines the SAW theory with organic film technology has been adopted to give an intensive insight into the responses of two-port SAW resonator coated with LB-film and cast-film after exposure to organic vapors.

Interaction of synthetic peptide corresponding to signal sequence of glucitol permease of Escherichia coli and its analogue with liposomes

The N-terminal signal sequence of glucitol permease of Escherichia Coli (Gut22) and its analogue (Gut22Ana) were synthesized. The analogue had a Pro residue substituting for the His at the 7th position of Gut22 and a Val residue substituting for the Glu at the 10th position. The intrinsic fluorescence emission spectra indicated that the binding of Gut22 with lipid bilayer was much stronger than that of Gut22Ana. The leakage experiments with calcein-loaded liposomes showed that Gut22 strongly perturbed lipid bilayers while Gut22Ana did not. The apparent partition constant of Gut22 for partitioning into phosphatidylserine/phosphatidylcholine bilayers was measured; the effect of membrane potential on the interaction of Gut22 with lipid bilayers was studied and the conformation changes of Gut22 and Gut22Ana upon interacting with liposomes were studied by the method of circular dichroism analysis.

[The changes of glucocorticoid receptor and beta-adrenoreceptor of lung tissues in SD rat asthma models and the effects of antiasthmatics on them]

OBJECTIVE

To observe the changes of glucocorticoid receptor (GR) and beta-adrenoreceptor (beta-AR) of lung tissue and the effects of oral procaterol, salbutamol and intraperitoneal (i.p.) or inhaled (i.h.) dexamethasone (Dex).

METHOD

The GR or beta-AR were determined by using 3H-dexamethasone and 3H-Dihydroalprenolol as ligand respectively, in groups of rat asthma models at 1, 3, 7, 14th day and groups received antiasthmatics on the 7th day after daily consecutive challenges.

RESULTS

The GR Bmax of asthma groups increased significantly after the first challenge, but decreased since the third day to a lower level than that of healthy control. The KD also decreased significantly since the third day. The beta-AR Bmax of asthma group gradually decreased to a significant low level on the 14th day. The Dex i.p. group had the lowest GR Bmax and the Dex i.h. group had the highest beta-AR Bmax among the treated. In the procaterol and salbutamol group, there had no decrease of GR Bmax compared with that of controls.

CONCLUSIONS

The GR and beta-AR levels of lung tissues changed after daily challenges. The GC played a down-regulation role on GR and an up-regulation role on beta-AR in lung tissues. The Dex i.h. had more advantages than Dex i.p. in terms of GR and beta-AR regulations.

Sequence-specific interactions of wound-inducible nuclear factors with mannopine synthase 2' promoter wound-responsive elements

A 318 bp mannopine synthase 2' (mas2') promoter element from the T-DNA of Agrobacterium tumefacians can direct wound-inducible and root-preferential expression of a linked uidA gene in transgenic tobacco plants. Wound inducibility is further enhanced by sucrose in the medium. Promoter deletion analysis indicated that the sucrose enhancement is conferred by a region extending from -318 to -213. DNase I footprinting indicated that an A/T-rich DNA sequence in this region is protected by tobacco nuclear factors. Regions extending from -103 to +66 and from -213 to -138 directed wound-inducibile expression of a linked uidA gene when placed downstream of a CaMV 35S enhancer or upstream of a truncated (-209) CaMV 35S promoter, respectively. DNase I footprinting analyses indicated that proteins from wounded tobacco leaves specifically bound to three contiguous motifs downstream of the mas2' TATA box. In addition to a common retarded band formed by the upstream wound-responsive element complexed with proteins from either wounded or unwounded tobacco leaves, two unique retarded bands were observed when this element was incubated with protein from wounded leaves. Methylation interference analysis additionally identified an unique motif composed of promoter elements and nuclear factors derived specifically from wounded tobacco leaves. We propose a model to describe the involvement of nuclear factors with mas2' promoter elements in wound-inducible gene expression.

Synthesis and application of hepatitis E virus peptides to diagnosis

Based on computer analysis of hydrophobicity and prediction of secondary structures for the full-length putative proteins encoded by open reading frame-1 (ORF-1), ORF-2 and ORF-3 of hepatitis E virus (HEV), we selected antigenic regions with hydrophilicity, beta-turn, and beta-sheet, and synthesized 7 peptides of possible epitope-containing regions of the polypeptide encoded by all 3 ORFs of HEV genomic RNA by Merrifield's method of solid-phase synthesis. The synthetic peptides were screened and identified by solid-phase enzyme-linked immunosorbent assay (ELISA). Three of the peptides (EH174 from ORF-1, EH286 from ORF-2 and EH362 from ORF-3) showed antigenic activity and possible application for the development of anti-HEV test kits (the peptide-based ELISA). The laboratory experiments and clinical trials showed that the kits, using a set of 3 synthetic HEV peptides as coating antigens, were of high specificity and exhibited good reproducibility. The small-scale seroepidemiological survey indicated high seroprevalence (14.3%) of anti-HEV in Tibetan populations. Additionally, the results also demonstrated good agreement with clinical findings, suggesting that the test kits will be of major use for immunodiagnosis and seroepidemiological surveys of HEV infection.

[Chemical constituents of stems and leaves of Fritillaria ussuriensis Maxim]

Three compounds were isolated from stems and leaves of Fritillaria ussuriensis. They were identified as adenosine, galacitiol and succinic acid.

Influence of intracellular Mn on the contractile inhibition caused by db cAMP, forskolin, and porcine relaxin in the circular muscle of the estrogen-treated rat uterus

Whether Mn ion permeates into circular muscle cells of the estrogen-treated rat uterus and how contractile inhibitions caused by db cAMP, forskolin, and relaxin are affected by treatment with Mn were examined. By exposing the muscle strip to 0.35 mM Mn added to Mg-free Krebs solution, the magnitude of phasic contractions evoked by electrical stimulation was reduced to 21.8 +/- 14.7% (n = 22) of control. Mn influx was measured by fura-2 fluorescence quenching at the Ca isosbestic excitation wavelength (360 nm). The contractile inhibitions caused by 30 microM db cAMP and 0.2 microM forskolin were enhanced after pretreatment with 0.35 mM Mn for 10 min, whereas the inhibition caused by 100 mU relaxin underwent enhancement or attenuation. These results are discussed in relation to those reported previously for the longitudinal muscle in which the influences of treatment with Mn were somewhat different.

Metabolic chiral inversion of stiripentol in the rat. I. Mechanistic studies

To study enantioselective aspects of the disposition of stiripentol (STP), a chiral allylic alcohol undergoing development as an antiepileptic drug, a stereoselective synthesis was developed and the configuration of the two enantiomers determined to be (R)-(+) and (S)-(-). Following a single oral dose (300 mg kg-1) of the individual enantiomers to adult male Sprague-Dawley rats, it was found that (R)-STP was transformed extensively to its antipode, whereas little inversion was detected when (S)-STP was administered. Studies on the mechanism of this apparently unidirectional chiral inversion revealed that the phenomenon was dependent on the presence of the side-chain C==C double bond, because the enantiomers of the corresponding saturated alcohol (D2602) did not interconvert in vivo. Experiments with analogs of STP labeled with deuterium or oxygen-18 at the chiral center showed that, whereas the deuterium was retained in vivo, partial loss of the 18O occurred from both enantiomers of the drug. Pretreatment of rats with pentachlorophenol (40 mumol kg-1 i.p.), an inhibitor of sulfation (and possibly other conjugation reactions), led to a marked decrease in the rate of conversion of (R)-STP to its antipode, suggesting that the chiral inversion phenomenon may be mediated, at least in part, by an enantioselective conjugation process.

Pretreatment with porcine relaxin and Mg ions enhances inhibitory effects of dibutyryl cyclic AMP in longitudinal muscle of estrogen-treated rat myometrium

Phasic contractions were evoked in Mg-free Krebs solution by electrical stimulation in the longitudinal myometrial strip taken from estrogen-treated rats, and the application of 30 microM dibutyryl cyclic AMP (db cAMP) for 15 min depressed the amplitude of contraction to 81 +/- 18% (+/- SD, n = 23) of the control. The contractile depression caused by db cAMP was not significantly altered by pretreatment with either 1 mM Mg (40 min) or 100 mU porcine relaxin (15 min) alone; however it was markedly enhanced to 22 +/- 30% (n = 7) of the control response by the combined pretreatment with Mg and relaxin. The enhancement lasted for longer than 2 h thereafter in Mg-free Krebs solution. It was discussed that some memory factor was induced by relaxin in the presence of 1 mM Mg to respond strongly to db cAMP.

Effects of Mg and Mn ions on the inhibitory action of cyclic nucleotides in the longitudinal myometrium of rat

Contractile response, membrane activity, and fluorescence signal from mag-fura-2 were measured on the longitudinal myometrium taken from estrogen-treated rat, and the influence of Mg and Mn ions on the inhibitory effects caused by db cAMP, 8-bromo cGMP, and db cGMP was investigated. Taking the Kd value of mag-fura-2 with Mg to be 2.0 mM, the intracellular Mg concentration was estimated to be 380 microM in the tissue incubated with Mg-free Krebs solution and 420 microM in the tissue exposed to Ca-free 40 mM K solution containing 15 mM Mg for 5 min, respectively. The phasic contractions generated by electrical stimulation in Mg-free Krebs solution were more strongly depressed by 30 microM db cAMP, 10 microM 8-bromo cGMP, and 1 mM db cGMP after the Mg loading treatment. The muscle was exposed to Ca-free 40 mM K solution containing 0.6 mM Mn for 10 min, and it was assumed that the muscle was loaded with Mn ions. After the Mn loading treatment, the contractile depression caused by 8-bromo cGMP and db cGMP was enhanced, whereas that by db cAMP was attenuated. These results were discussed in relation to the influence of intracellular load with Mg or Mn on the inhibitory actions caused by isoprenaline, forskolin, and relaxin.

Model-free numerical deconvolution of recirculating indicator concentration curves

This paper investigates two model-free methods for numerical deconvolution of recirculating indicator concentration curves. The two methods, damped least squares and discrete orthogonal polynomial deconvolution, are applied to simulated data to verify the reliability of the algorithms. Both deconvolution methods provide damping that results in estimated transport functions that are smooth and reasonable estimates of the actual simulated transport function. On convolution with the simulated input curve, the estimated transport functions provide good fits to the simulated output curve. In addition, methods for identifying an optimal solution and for truncating the artifactually long oscillatory tails of the estimated transport functions are proposed, which appear to allow for reasonably accurate estimation of the mean transit times and variances of the transport functions as well. When either method was applied to indicator dilution data obtained from the pulmonary artery and left atrium, it was computationally stable while producing transport functions that when convolved with the input concentration curves provided good fits to the output concentration curves. The combined simulation and experimental results suggest that the proposed methods should be useful for estimating circulation transport functions from indicator dilution data.