Relationship between Asbestos Exposures and 8-Hydroxydeoxyguanosine Levels in Leukocytic DNA of Workers at a Chinese Asbestos-material Plant

The objective of the study was to evaluate the level of 8-hydroxydeoxyguanosine (8-OHdG) in DNA of peripheral-blood leukocytes as a biological marker of asbestos exposure and/or its fibrotic effects in an occupational population exposed to asbestos. The setting was a large-scale asbestos plant in China producing brake linings, asbestos rubber, and textile using chrysotile. From a base population of active and retired workers with various levels of cumulative exposure to asbestos and grades of asbestosis, 39 study subjects were randomly selected to reflect incremental grades of asbestosis based on Chinese diagnostic standards. They consisted of 19 "normal" (control) and ten "suspected" and ten "definite" asbestosis-grade subjects, group-matched for age and sex. Leukocytic DNA was extracted from 5-mL samples of peripheral blood and 8-OHdG level measured by high-pressure liquid chromatography. A cumulative asbestos exposure index (CEI) was calculated for each subject as the summed product of duration and level of asbestos exposure per job, incorporating a job-exposure matrix. Geometric mean 8-OHdG levels showed a positive gradient in relation to increasing grades of asbestosis (control: 1.78, suspected: 2.21, definite: 2.58), with a significant difference between the control and definite-asbestosis subgroups (p < 0.05). The 8-OHdG level of the two subgroups combined as one "asbestosis" group was significantly higher than that of the control group (control: 1.78, asbestosis: 2.39, p = 0.01). Further, 8-OHdG levels were moderately correlated with CEIs for all subjects (r = 0.35, p < 0.05) and with grades of asbestosis for all (r = 0.47, p < 0.01) and for male subjects (r = 0.43, p < 0.05). In multiple regression analyses, grade of asbestosis explained 27% of the total variation in 8-OHdG and was a better predictor than CEI or duration of exposure. Thus, the 8-OHdG level in leukocytic DNA is related to grade of asbestosis and to individual cumulative exposure and may serve as a biologic marker reflecting the status of oxidative DNA damage by asbestos.

Upregulation of interferon-alpha receptor expression in hydroxyurea-treated leukemia cell lines

BACKGROUND

Interferon-alpha (IFN-alpha) shows its antitumor effect through binding to specific cell surface receptors. A DNA synthesis inhibitor, hydroxyurea (HU), has been successfully combined with IFN-alpha to improve the efficiency of IFN therapy for chronic myelogenous leukemia (CML). To understand the mechanism of this combination effect, expression of IFN-alpha receptors on the CML cell line, K562, was studied before and after treatment with HU.

METHODS

Cells were treated with HU at a dose of 0, 0.1, 0.2, or 0.4 mmol/L for 48 hours. Binding assays were performed using 125I-labeled IFN-alpha at 4 degrees C. Cell cycle analysis was carried out using flow cytometer following staining cellular DNA with propidium iodide. Northern blot analysis was performed to evaluate the inducibility of interferon regulatory factor-1 (IRF-1) gene expression by IFN-alpha.

RESULTS

Hydroxyurea-treated cells showed a dose- and time-dependent increase in binding of 125I-labeled IFN-alpha (maximal 2.5-fold). The increase of binding was caused by an increase in the number of binding sites with a constant receptor affinity. Similar results were obtained in the Burkitt's lymphoma cell line, Daudi. Cell cycle analyses suggested that upregulation of the IFN receptor may have occurred as a result of the alteration in the cell cycle distribution. Furthermore, IFN-alpha induction of the IFN-inducible gene IRF-1 mRNA in HU-treated K562 cells was 2-fold higher than that in untreated cells.

CONCLUSIONS

Thus, HU may have an ability to enhance the response to IFN-alpha probably because of its ability to upregulate the IFN-alpha receptors, suggesting that this may be involved in the mechanism of effective combination therapy of IFN-alpha with HU.

[Peripheral carcinoid tumor of the lung presenting as a solitary mass shadow on a chest roentgenogram and diagnosed by CT-guided percutaneous needle biopsy]

A 59-year-old woman was referred to our clinic because a solitary mass shadow (2.5 cm in diameter was seen in the left lower lung field on a chest roentgenogram. Transbronchial biopsy via a fiberoptic bronchoscope did not yield a definitive diagnosis. Examination of a specimen obtained by CT-guided percutaneous needle biopsy revealed that the tumor consisted of small cells proliferating in a solid, tubular, pseudoglandular, and follicular pattern, which suggested the diagnosis of carcinoid. A left lower lobectomy was performed, and several hilar and mediastinal lymph nodes were also removed. The tumor cells did not show pleomorphism of nuclei, mitotic activity, or necrosis. Grimelius and immunohistochemical stains for chromogranin. A, neuron-specific-enorase, synaptophysin, and serotonin were positive. These findings confirmed the diagnosis of carcinoid CT-guided percutaneous needle biopsy can be useful for the diagnosis of peripheral carcinoid and other peripheral lung tumors.

Intraosseous ganglion communicating with soft tissue counterpart

We report the imaging and pathological findings of a rare case of intraosseous ganglion communicating with extraosseous counterpart. Both counterparts contain air and show rim-enhancement on T1-weighted images. Histopathologically, the enhanced-rim consists of reactive proliferation of capillary vessels due to degeneration.

[A mesenchymal malignant mesothelioma that changed from mixed type to purely sarcomatous type]

A 65-year-old man was admitted to the hospital because of an abnormal shadow on a chest roentgenogram. A diagnosis of mixed-type malignant mesothelioma was made after transcutaneous needle biopsy and thoracoscopic biopsy. The tumor was considered to be inoperable because it had diffusely invaded surrounding tissue, and therefore the patient was treated with chemotherapy only. About one year later, he died of acute pneumonia. At autopsy, a mesenchymal malignant mesothelioma that did not have an epithelial component was found. We know of no previous report of a case in which a tumor with a biopsy-proven epithelial component apparently changed to a purely sarcomatous type. No satisfactory explanation for this phenomenon has been offered.

Immunomodulatory effects of a plasmid expressing B7-2 on human immunodeficiency virus-1-specific cell-mediated immunity induced by a plasmid encoding the viral antigen

B7 co-stimulation is essential for activating resting T cells following antigen recognition by the T cell receptor. To determine whether B7 has adjuvant activities on human immunodeficiency virus type-1 (HIV-1)-specific immunity induced by inoculation of a plasmid encoding HIV-1 env and rev (DNA vaccine), B7-1 and B7-2 expression plasmids were co-inoculated with the DNA vaccine. The delayed-type hypersensitivity response and cytotoxic T lymphocyte (CTL) activity were significantly enhanced when B7-2 expression plasmid was co-inoculated with the DNA vaccine, but were unaffected when the B7-1 expression plasmid was used with the vaccine instead. The immunological response enhanced by B7-2 decreased below the level of mice immunized with the DNA vaccine in combination with CTLA4Ig, an inhibitor of the B7/CD28 co-stimulatory signal, suggesting that this signal is critical for the enhanced response induced by co-inoculation of the DNA vaccine and B7-2 expression plasmid. This enhancement appeared to occur via an interferon-gamma (IFN-gamma)-dependent mechanism, as combined administration of the B7-2 plasmid and neutralizing anti-IFN-gamma antibody abrogated the virus-specific cell-mediated immunity. These results suggest that this gene-based co-inoculation strategy using HIV-1 viral antigen and B7-2 co-stimulatory molecule could be a powerful means of combating HIV-1 infection.

[Complete remission achieved by L-asparaginase, vincristine and prednisolone (LVP) therapy in secondary leukemia (M5a type) with an MLL gene rearrangement]

A 16-year-old boy was operated upon for synovial sarcoma of the right thigh and underwent chemotherapy consisted of adriamycin (320 mg), cisplatin (780 mg), etoposide (4,200 mg) and ifosfamide (30,000 mg). He developed secondary leukemia 18 months after the chemotherapy. Acute lymphoblastic leukemia (L3) was initially diagnosed because of poor staining of alpha-naphtyl butylate esterase and induction chemotherapy with the LVP regimen (L-asparaginase 5,000 U/m2 day 8-21, vincristine 1.5 mg/ m2 day 1, 6, 11, 16, 21, 26, prednisolone 40 mg/m2 day 1-28) was performed. After the therapy was initiated, the leukemia was finally diagnosed as acute momocytic leukemia (M5a) because of the following data; blasts were positive for CD33 and HLA-DR and negative for CD10, CD19 and CD20; serum lysozyme was 104.0 micrograms/ml; re-evaluation revealed that blasts were strongly positive for alpha naphtyl butyrate esterase in a small part of the slides; 95% of the bone marrow cells showed t (9; 11) chromosomal aberration; gene rearrangement was positive for MLL and negative for JH, JK and TCR C beta 1. Nevertheless, complete remission was obtained after 1 course of LVP therapy. He received bone marrow transplantation from an unrelated volunteer donor after 3 courses of consolidation therapy. He has remained in complete remission for 16 months.

Effects of fenoterol on ventilatory response to hypercapnia and hypoxia in patients with chronic obstructive pulmonary disease

BACKGROUND

It has previously been shown that fenoterol, a beta 2 adrenergic agonist, increases the ventilatory response to hypoxia (HVR) and hypercapnia (HCVR) in normal subjects. The effects of beta 2 adrenergic agonists on chemoreceptors in patients with chronic obstructive pulmonary disease (COPD) remain controversial. This study was designed to examine whether fenoterol increases the HVR and HCVR in patients with COPD.

METHODS

The HCVR was tested in 20 patients using a rebreathing method and the HVR was examined using a progressive isocapnic hypoxic method. The HCVR and HVR were assessed by calculating the slopes of plots of occlusion pressure (P0.1) and ventilation (VE) against end tidal carbon dioxide pressure (PETCO2) and arterial oxygen saturation (SaO2), respectively. Spirometric values, lung volumes, and respiratory muscle strength were also measured. The HCVR and HVR were examined after the oral administration of fenoterol (15 mg/day) or placebo for seven days.

RESULTS

Fenoterol treatment increased the forced expiratory volume in one second (FEV1) and inspiratory muscle strength. In the HCVR the slope of P0.1 versus PETCO2 was increased by fenoterol from 0.35 (0.23) to 0.43 (0.24) (p < 0.01). Moreover, the P0.1 at PETCO2 of 8 kPa was higher on fenoterol than on placebo (p < 0.05) and the VE was also greater (p < 0.01). In the HVR fenoterol treatment increased the P0.1 at 80% SaO2 from 0.90 (0.72) to 0.97 (0.55) kPa (p < 0.05) while the slopes of the response of P0.1 and VE were not changed.

CONCLUSIONS

Fenoterol increases the ventilatory response to hypercapnia in patients with COPD, presumably by stimulation of the central chemoreceptor. The hypoxic ventilatory response is only slightly affected by fenoterol.

Patterns of inspiratory muscle shortening during hypoxia and hypercapnia in dogs

The shortening of parasternal intercostal muscles (Para) and crural (Cru) and costal diaphragms (Cos) are not precisely understood. We therefore examined shortening patterns of these inspiratory muscles by using chronically implanted sonomicrometers in dogs. To avoid acute effects of surgery, measurements were performed 3 weeks after implanting the sonomicrometers. Patterns of length changes of Para, Cru, and Cos were measured during hypoxia and hypercapnia under two levels of anaesthesia. Respiratory length change (delta L) was assessed as a percentage change relative to the resting length at functional residual capacity (LFRC). Peak tidal shortening was defined as the maximal change from LFRC (delta L/LFRC). Under light anesthesia, the delta L/LFRC was the same among the three muscle groups at all tidal volumes (VT). Under deep anaesthesia, the delta L/LFRC both of Cru and Cos exceeded that of Para. Under light anaesthesia, the maximal shortening velocity ((delta L/LFRC)/delta t) of Cru was greater than that of Para. Under deep anaesthesia, the (delta L/LFRC)/delta t of Para was exceeded by that both of Cru and Cos. Furthermore, the (delta L/LFRC)/delta t of each inspiratory muscle was greater during hypoxia than during hypercapnia at equal volume. We conclude that: 1) the contribution of the diaphragm to ventilation increases during deep anaesthesia; 2) the muscle shortening velocity during hypoxia or hypercapnia is lower in parasternal intercostal muscles than in the diaphragm; and 3) there is no difference in the shortening pattern between crural and costal diaphragms.

Contribution of oxygen radicals to DNA cleavage by quinone compounds derived from phenolic antioxidants, tert-butylhydroquinone and 2,5-di-tert-butylhydroquinone

The effects of synthetic phenolic antioxidants, tert-butylhydroquinone (TBHQ), 2,5-di-tert-butylhydroquinone (DTBHQ) and 3-tert-butyl-4-hydroxyanisole (BHA), on DNA cleavage were examined with supercoiled plasmid DNA, pUC18, in vitro. Extensive single and double strand breaks of DNA by TBHQ were observed and almost all the DNA was converted to the linear form at 10(-2) M. The cleavage was stimulated by both CuCl2 and FeCl2, though the effect of FeCl2 was smaller. Metal ion chelators and some oxygen radical scavengers inhibited the cleavage. The generation of TBHQ semiquinone radical and hydroxyl radical in the presence of copper was demonstrated by ESR spectroscopy. DTBHQ also caused DNA cleavage, though its effect was much smaller than that of TBHQ. BHA had no effect in the experimental systems employed. Oxygen radicals were considered to contribute to the DNA cleavage by TBHQ and DTBHQ.

In vivo fatiguing contraction of rat diaphragm produces hydroxyl radicals

It is suggested that free radical generation is a cause of muscle fatigue from in vitro studies. We examined whether hydroxyl radical would be generated in an in vivo fatiguing contraction of the diaphragm. Diaphragmatic fatigue was induced in rats by the in vivo rhythmic electrical stimulation of the diaphragm under mechanical ventilation for 30 min. The force-frequency relationship of a diaphragmatic muscle strip was assessed, and the production of hydroxyl radical in muscle strip was evaluated by measuring the metabolites of a reaction of salicylate with hydroxyl radical (2,3- and 2,5-dihydroxybenzoate [DHBA]). After fatiguing contraction, the contractile force of the diaphragm was decreased by approximately 58% at all stimulating frequencies (P < 0.01). There was more 2,3-DHBA in the fatigued muscles compared with the control muscle (219 +/- 22 ng/g tissue versus 109 +/- 17, respectively, P < 0.01) and 2,5-DHBA (198 +/- 23 ng/g tissue versus 84 +/- 14, respectively, P < 0.01). There was a significant relationship between contractile force and the sum of 2,3- and 2,5-DHBA (r = -0.71, P < 0.01). These results suggest that the development of fatigue in the diaphragm is related to the generation of hydroxyl radical.

HIV-1-specific cell-mediated immunity is enhanced by co-inoculation of TCA3 expression plasmid with DNA vaccine

We developed a candidate DNA vaccine designated pCMV160IIIB with pcREV (pCMV160IIIB/REV) that encodes gp160 of human immunodeficiency virus (HIV)-1IIIB and Rev driven by the cytomegalovirus (CMV) promotor. This vaccine induced both HIV-1-specific antibodies and cytotoxic T lymphocyte (CTL) activity. In the present study, we inoculated the TCA3 expression plasmid into mouse skeletal muscle with pCMV160IIIB/REV to determine whether this cytokine expression plasmid was able to modify the immune response. Results of a delayed-type hypersensitivity (DTH) assay using footpad swelling as well as those of a CTL assay clearly demonstrated that cell-mediated immunity (CMI) elicited by co-inoculation of pCMV160IIIB/REV with the TCA3 expression plasmid was markedly enhanced compared with that obtained using pCMV160IIIB/REV alone. When TCA3 expression plasmid was inoculated with anti-TCA3 antibody, enhancement of the DTH response was suppressed below the level of that obtained with pCMV160IIIB/REV alone. The titre of HIV-1-specific IgG2a was slightly high when pCMV160IIIB/REV was co-inoculated with this plasmid, suggesting that T-helper 1 (Th1) response was predominant in TCA3-inoculated mice. Infiltration of mononuclear cells was seen in the muscles at sites where TCA3 expression plasmid had been inoculated. Our present data suggest that TCA3 expression plasmid has potent adjuvant activity that results in an augmented CMI response.

[Minimally differentiated hypoplastic leukemia in two elderly patients]

Patient 1; A 78-year-old woman was admitted to our hospital because of general malaise. Her peripheral blood count showed bicytopenia of 900/microliter with 2% blasts, 7.0 g/dl hemoglobin, and 199,000/microliter platelets. Examination of bone marrow revealed hypocellular marrow with peroxidase-negative blasts (89%). Surface marker analysis of blast cells revealed CD13 agents. Electron-microscopically, myeloperoxidase staining was positive. The diagnosis was hypoplastic leukemia in which blasts had a feature of minimally differentiated acute myeloid leukemia (AML-MO). Patient 2; A 78-year-old man was admitted to our emergency unit because of dizziness and dyspnea on exertion. Examination of peripheral blood showed pancytopenia but no blast cells. Examination of bone marrow showed a markedly hypocellular marrow with 38% blast cells. These blast cells were negative for myeloperoxidase and they had CD13 antigen on their surfaces. The diagnosis was minimally differentiated hypoplastic leukemia. At the time of this writing these two patients had been receiving only red cell transfusions for about six months, and the disease had not progressed.

Synthetic peptide from the V3 loop consensus motif with a potent anti-HIV activity inhibits ristocetin-mediated vWF-GPIb interaction

The V3 loop consensus motif. Arg-Gly-Pro-Gly-Arg-Ala-Phe-Val-Thr-Ile (HIV-1 IIIB), inhibits an interaction of HIV with CD4-positive lymphocytes. Recently, both proline-rich peptides and peptides containing proline-glycine loops (beta-turns) form a complex with ristocetin dimers. These peptides interact with ristocetin-loaded platelet membrane glycoprotein (GP) Ib and act as inhibitors of von Willebrand factor (vWF)-GPIb interaction by preventing the subsequent formation of ristocetin dimer bridges. The Pro-Gly sequence is also present in the V3 loop consensus motif, Arg-Gly-Pro-Gly-Arg-Ala-Phe-Val-Thr-Ile (HIV-1 IIIB). In this report, we have evaluated the effect of the HIV-1 IIIB peptide on vWF binding to GPIb. This peptide only inhibited vWF binding to GPIb as well as platelet aggregation in the presence of ristocetin while it had no effect on botrocetin-mediated vWF interaction with platelets. The peptide inhibited a binding of anti-vWF monoclonal antibody (RG-46) to immobilized vWF. Furthermore, ristocetin inhibited the binding of HIV-1 IIIB peptide to immobilized CXC-chemokine receptor-4 (CXCR-4) peptide. These results indicate that ristocetin may prevent HIV infection and would be useful a tool to understand the mechanism of HIV tissue tropism and infection.

Eradication of minimal residual disease during graft-versus-host reaction induced by abrupt discontinuation of immunosuppression following bone marrow transplantation in a patient with Ph1-ALL

We observed a patient in whom graft-versus-host disease (GVHD) appeared to induce a positive effect. This 32-year-old male with Philadelphia chromosome-positive acute lymphoblastic leukemia received a bone marrow transplant (BMT) from an HLA-identical sibling donor. We analyzed the bone marrow with the reverse transcriptase-polymerase chain reaction to screen for the minor bcr/abl transcript, which indicates the presence of minimal residual disease (MRD). MRD was present in the pre- and post-transplant phases. There was no evidence of acute GVHD by post-transplant day 45. We abruptly discontinued the immunosuppressive therapy in an attempt to eliminate MRD by inducing an antileukemic reaction during GVHD. GVHD associated with diarrhea and liver dysfunction developed on day 64. On day 105, MRD disappeared and GVHD was treated with prednisolone and cyclosporin. The disappearance of MRD may have been due to the graft-versus-leukemia (GVL) effect mediated by the alloimmune response of donor T lymphocytes. These findings suggest that induction of the GVL effect may be useful for eliminating MRD after BMT in leukemia patients at high risk of recurrence of the disease.

Formation of 8-hydroxydeoxyguanosine in calf thymus DNA treated with tert-butylhydroquinone, a major metabolite of butylated hydroxyanisole

Oxidative DNA damage caused by butylated hydroxyanisole (BHA), 2-tert-butyl(1,4)hydroquinone (TBHQ, a metabolite of BHA) and 2,5-di-tert-butyl(1,4)hydroquinone (DTBHQ), as well as 2,6-di-tert-butyl(1,4)benzoquinone (BHTQ, a metabolite of butylated hydroxytoluene), was evaluated by measuring the formation of 8-hydroxydeoxyguanosine (8OHdG) in calf thymus DNA. 8OHdG formation was greatly increased by TBHQ in a concentration-dependent manner. This effect was strongly enhanced by CuCl2 and suppressed by EDTA, bathocuproinedisulfonic acid disodium salt, methionine, glutathione reduced form or catalase, but was not affected by mannitol, sodium benzoate or sodium azide. Thus, TBHQ-induced 8OHdG formation may be mediated by copper. DTBHQ also induced the formation of 8OHdG, though to a much lesser extent than TBHQ, and its effect was stimulated by CuCl2. BHA had a small enhancing effect at high concentration, only in the presence of CuCl2, whereas in the case of BHTQ, it occurred both in the presence of CuCl2 and FeCl2.

Interferon-gamma induces Ice gene expression and enhances cellular susceptibility to apoptosis in the U937 leukemia cell line

The roles of interferons (IFNs) in apoptosis are not fully understood. In this study we show that in the U937 monoblastic leukemia cell line, pretreatment with IFN-gamma enhanced sensitivity to apoptosis triggered by gamma-irradiation or antitumor agents (etoposide or adriamycin), as well as by anti-Fas antibody. In addition, IFN-gamma caused an increased expression of the interleukin-1 beta-converting enzyme (Ice) gene, following strong induction of the interferon regulatory factor-1 (IRF-1) gene, the product of which is a transcriptional activator of the Ice gene. An inhibitor of ICE/Ced-3 family proteases, Z-Asp-CH2-DCB, blocked apoptosis in control cells as well as in IFN-gamma-pretreated cells. These results suggest that enhanced susceptibility of IFN-gamma-pretreated cells to apoptosis is mediated through the induction of Ice by IRF-1. This pathway is not affected by interleukin-1 beta (IL-1 beta) since neutralizing antibody against IL-1 beta failed to suppress the IFN-gamma-mediated enhancement of cell death, and IL-1 beta itself did not mimic the effect of IFN-gamma.

Effect of estrogen replacement therapy on hepatic triglyceride lipase, lipoprotein lipase and lipids including apolipoprotein E in climacteric and elderly women

Estrogen provides beneficial effects on hyperlipidemia in climacteric and elderly women. In this study of 68 women (37 to 67 years old), hepatic triglyceride lipase (HTGL), lipoprotein lipase (LpL) serum lipids and apolipoproteins were analyzed to investigate the effects of estrogen replacement therapy (ERT). After menopause, LpL, total cholesterol, low-density lipoprotein (LDL)-cholesterol, and apolipoprotein B increased. But ERT suppressed total cholesterol, LDL-cholesterol, apolipoprotein B, and especially apolipoprotein E in menopausal women. The mechanism was thought that ERT significantly suppressed HTGL, but LpL was not affected. Estrogen also increases hepatic LDL receptors and accelerates transfer of serum LDL-C (and TC). It was said that HTGL accelerates conversion of intermediate-density lipoprotein (IDL) to LDL. The suppression of HTGL by the ERT may decrease conversion of IDL to LDL and lower LDL-C (and TC). These estrogen's beneficial effects on lipids, may prevent the atherosclerosis. In addition, apolipoprotein E increases senile plaques in senile dementia-Alzheimer's type. The decrease in apolipoprotein E with ERT may be related to cognitive functions of elderly women.

Value of intraoperative intrathoracic ultrasonography during video-assisted thoracoscopic pulmonary resection

Recent advances in endoscopic surgical equipment, video monitoring, and endoscopic surgical techniques have expanded the application of thoracoscopic surgery to pulmonary resection. One of the major limitations of this technique is the difficulty in identifying invisible pulmonary nodules in which manual palpation is not possible. To resolve this problem, we employed intraoperative intrathoracic ultrasonography during video-assisted thoracoscopic pulmonary resection. We conclude that intraoperative ultrasonography during thoracoscopic pulmonary resection is useful to identify pulmonary nodules, except inflammatory lesions.

[Airway hyperresponsiveness and airway mucosal permeability]

The relationship between airway mucosal permeability and airway hyperresponsiveness was examined with tachykinins, their selective antagonists, and superoxide dismutase in male Hartley guinea pigs. In animals with ozone-induced airway inflammation, airway hyperresponsiveness and mucosal permeability increased concurrently but there was a time lag before the increase in airway vascular permeability. To study the role of tachykinins in the increases in mucosal permeability and in hyperresponsiveness, we used a neurokinin-receptor antagonist, CP-96345, and a neurokinin-2 receptor antagonist, SR-48968. CP-96345 had no significant effect, but SR-48968 reduced the increase in airway mucosal permeability; their effects on airway hyperresponsiveness were the opposite of their effects on airway permeability. Tachykinins themselves, both substance P and neurokinin A, significantly increased airway mucosal permeability. Superoxide dismutase, a scavenger enzyme of superoxide, reduced the ozone-induced airway hyperresponsiveness. These data suggest that the factors causing airway hyperresponsiveness differ from those that influence mucosal permeability, but it is possible that these pathophysiologic conditions are caused by the same substances or processes.

Investigation of genetic risk factors associated with alcoholism

Alcoholism is a multifactorial disease influenced by genetic-environmental interaction. Genetic variation of the receptor may be associated with alcohol dependence due to its modified function in behavioral and physiological responses. In the present study, polymorphic alleles of cholecystokinin B receptor (CCKBR), serotonin 1A receptor (HT1AR) genes, and mitochondrial DNA were analyzed. DNAs were isolated from the blood samples of 112 healthy controls and 106 alcoholics. Genetic variation was detected by SSCP analysis, followed by direct sequencing of polymerase chain reaction product as well as restriction fragment-length polymorphism. Three different mutations were found in the exon 3 sequence of CCKBR: His (CAT) at aa207-->His (CAC) (5.4%), Arg (CGC) at aa215-->His (CAC) (4.5%), and Val (GTG) at aa138-->Met (ATG) (0.9%) in controls. Genotypic distribution of alcoholics was not significantly different with that in controls. A proline (CCG) to leucine (CTG) substitution at amino acid 16 of HT1AR was found in alcoholics (4.5%) and in controls (4.7%). This mutation site of HT1AR was different in comparison with the variants reported by Nakhai et al. (Biochem Biophys. Res. Commun. 210:530-536, 1995). Analysis of the mitochondrial DNA showed that a 491 bp deletion in the sequence of ATPase exists as heteroplasmy in 58% of alcoholics, but not in controls. Heteroplasmic deletion of mitochondrial DNA may be a useful marker for alcohol abuse. Further study is undergoing to elucidate the cause and significance of this deletion in alcoholics.

Electrically Induced Shear Waves in Colloidal Crystals

The static light scattering method is used for the detection of acoustic waves induced in colloidal crystals and liquids by low-frequency electric pulses. The method is sensitive to both density and shear modes and can be applied for the study of the liquid-crystalline phase transitions. At low fields the variations of light scattering intensity follow both the amplitude and the phase variations of the wave motion and enable the determination of resonance parameters, hence of viscoelastic parameters of the colloidal system.