Relationships between Responsiveness of the Bronchi to Acetylcholine and Cyclic AMP Response of Lymphocytes to Beta1- and Beta2-Adrenergic Receptor Stimulation in Patients with Asthma

Decreased response of beta-adrenergic receptor has been considered to he one of the causes of increased responsiveness of the bronchi in asthma. Since beta-adrenergic receptor has two subtypes, beta₁ and beta₂, and the bronchodilating effect of beta stimulants is mediated by beta₂-receptor, responsiveness of the bronchi is expected to correlate to the cyclic AMP response of lymphocytes to a beta₂-stimulant. Responsiveness of the bronchi was expressed as respiratory threshold to acetylcholine (RT-Ach), which was the minimal concentration of acetylcholine solution to cause an initial decrease of FEV₁ of more than 20% of the baseline value. Beta₁ and heta₂-responses were expressed as the increments of cyclic AMP content of 10⁶ lymphocytes incubated with norepinephrine (beta₁-stimulant) and salbutamol (beta₂-stimulant).
RT-Ach showed a significant correlation with the beta₂-cyclic AMP response of lymphocytes, but not with the beta₁ -response among patients with asthma. Sixteen symptomatic patients on continuous beta-stimulants showed lower RT-Ach value and diminished beta₂-receptor activity of lymphocytes compared with 14 patients in remission. These results suggest that selective beta₂-adrenergic blockade may he one of the causes of bronchial hypersensitivity in asthma, though it should be noted that in this study beta-adrenergic responses were examined in lymphocytes and were compared with the responsiveneness of the bronchi. Possible beta-receptor subsensitivity induced by administration of beta-stimulants is discussed.     

Polymerization mechanism of N-carboxy-α-amino acid anhydride by organometallic compounds. II.. Reaction with organozinc compounds

Reactions of N-carboxy-α-amino acid anhydride (NCA) with dialkylzinc or related organozinc compounds were studied to elucidate the polymerization mechanism of NCA by dialkylzinc as initiator. The first stage of initiation reaction is a hydrogen abstraction reaction of dialkylzinc from NH group of α-amino acid NCA resulting in the formation of an activated NCA. The second stage of initiation is a reaction between two molecules of the activated NCA forming a zinc carbamate group. Propagation reaction is a carbonyl addition of the zinc carbamate group to the activated NCA to form a mixed anhydride which changes into an amide group releasing carbon dioxide. Regeneration of the activated NCA is supposed to be done by the reaction of free α-amino acid NCA with the zinc atom bonded to nitrogen atom at the growing chain end.     

Effect of thromboxane A2 synthetase inhibitor on immediate-type hypersensitivity reactions

The effect of the thromboxane (TX) A2 synthetase inhibitor, OKY-046, on human leukocyte histamine release and bronchial hypersensitivity in asthmatic subjects was evaluated. It was found that OKY-046 inhibited IgE- and Ca2+ ionophore A23187-mediated leukocyte histamine release in a dose-dependent fashion (IC50: 1.0 and 3.0 X 10(-3) M, respectively) and that OKY-046 could diminish bronchial hypersensitivity, determined by leukotriene D4 inhalation, following a 2-week oral medication. These data suggest that the TXA2 synthetase inhibitor can produce favorable effects upon the course of immediate-type hypersensitivity reactions.     

TCR repertoire in early fetal mouse thymus

We investigated the rearrangement and expression of TCR genesin mouse fetal thymus organ culture, a system that avoids subsequententry of hematopoietic precursor cells. The first observablerearranged TCR gene was homogeneous V2-J2, detectable as earlyas fetal day 11 (d11) in the thymic primordla. The productiveTCR was homogeneous V5-J1, first detectable in d13 thymocytes,followed by adult-type TCR (V4 and V7). Sequence analysis ofTCR revealed five types of V-J junctional sequences. In thevery early stage, a homogeneous V-J junction is generated viaa short homology sequence in the coding region (Type I), whilea short homology sequence in the P-nucleotlde rather than thecoding region is used in the following stage (Type II). In thelater embryonic stages, diverse V-J junctions are generatedby well-known mechanisms, such as P-nucleotide (Type III), N-regioninsertion (Type IV) or trimming of the coding ends (Type V).These findings suggest that the generation of homogeneous TCR (V2 and V5) in the early fetal stages is due to the intrinsicrearrangement mechanisms and is in stage specific manner.     

Inhibitory effect of methyl 7-butyl-4,5,6,7-tetrahydro-3-methylamino-4,6-dioxo-5-propyl-2H-pyrazolo [3,4-d] pyrimidine-2-carboxylate (AA-2379) on type III allergic (Arthus) reaction

Methyl 7-butyl-4,5,6,7-tetrahydro-3-methylamino-4,6-dioxo-5-propyl-2H-pyrazolo[3,4-d]pyrimidine-2-carboxylate (AA-2379), a non-steroidal, non-acidic agent, markedly inhibits type III allergic (Arthus) reaction; the ID₅₀ values of AA-2379 in the rat reversed passive Arthus pleurisy, the rat active Arthus pleurisy, and the reversed passive Arthus reaction in rat skin were 5–10 mg/kg, p.o., and 30 mg/kg of AA-2379 inhibited the active Arthus reaction in rabbit skin by about 50%. Dexamethasone, but not acidic non-steroidal anti-inflammatory drugs and aminopyrine, inhibited the Arthus reaction. The vascular permeability in the reversed passive Arthus pleurisy is enhanced biphasically in the early response mediated by physiologically active amines, prostaglandins, and leukotrienes, and in the late response mediated by complements and polymorphonuclear leukocytes (PMNs). AA-2379 inhibited the late response more potently than the early one. Furthermore, when given after the early response was reduced, AA-2379 obviously inhibited the late response. Rat zymosan-induced paw edema and mouse zymosan-activated serum-induced peritonitis, mediated by complements, were dose-dependently inhibited by AA-2379; the ID⁵⁰ values were 11.4 and 10.2 mg/kg, p.o., respectively. The results suggest that AA-2379 differes from non-steroidal anti-inflammatory agents in strongly inhibiting the late response of the Arthus reaction, which associated with PMNs.     

Catalase, a Specific Antigen in the Feces of Human Subjects Infected with Helicobacter pylori

Recently, we reported the production of three new monoclonal antibodies with high specificity for a Helicobacter pylori antigen suitable for diagnosis of H. pylori infection. The aim of the present study was to identify the antigen recognized by these monoclonal antibodies concerning both H. pylori and the feces of human subjects infected with H. pylori. The cellular antigen was purified from an H. pylori cell extract by immunoaffinity column chromatography with the monoclonal antibody as a ligand. The amino-terminal amino acid sequences (eight residues) of the purified antigen and H. pylori catalase were the same. The molecular weights of native and subunit, specific catalase activity, and UV and visible spectra of the purified antigen were in good agreement with those of H. pylori catalase. The human fecal antigens were purified from two fecal samples of two H. pylori-positive subjects by ammonium sulfate precipitation, CM-Sephadex C₅₀ chromatography, and the same immunoaffinity chromatography used for the H. pylori cellular antigen. The fecal antigens had catalase activity. The amino-terminal amino acid sequences (five residues) of the human fecal antigen and H. pylori catalase were the same. The monoclonal antibodies reacted with the native cellular antigen, but did not react with the denatured antigen, human catalase, and bovine catalase. The results show that the target antigen of the monoclonal antibodies is native H. pylori catalase and that the monoclonal antibodies are able to specifically detect the antigen, which exists in an intact form, retaining the catalase activity in human feces.     

Study of monoclonal gammopathy in Kagawa Prefectural Central Hospital

We investigated 361 patients with monoclonal gammopathy in whom immunoelectrophoresis was performed (1,037 tests) between 1986 and 2002 at Kagawa Prefectural Central Hospital. In this study, we identified 222 patients with monoclonal gammopathy of undetermined significance (MGUS). Malignant transformation of MGUS to multiple myeloma occurred in 15 patients (6.8%). No significant differences were observed in the means of total protein (TP), albumin (Alb), albumin/globulin ratio (A/G ratio), IgG, IgA, or IgM level in the initial examination between the patients who remained as MGUS and patients with malignant transformation of MGUS. However, the rate of progression to malignancy was high when the levels of normal immunoglobulins other than M protein were below the normal range. Since the number of MGUS cases detected and the number of protein fractionation performed were proportionate, and MGUS was found by protein fractionation in routine tests, protein fractionation is essential for detection of MGUS, and it is necessary to add serum protein fractionation to routine initial examination. In addition, long-term follow-up of patients with monoclonal gammopathy and preparation of a database of patient information are useful for monitoring the outcome.     

Inhibitory influence of a new steroidal anti-androgen, TZP-4238, on prostatic hyperplasia in the beagle dog.

The effect of a synthetic steroidal anti-androgen, TZP-4238, on spontaneous benign prostatic hyperplasia (BPH) in dogs was investigated. Old male beagle dogs (5-9 years old) were divided into three experimental groups. Group 1 consisted of BPH controls. Groups 2 and 3 received TZP-4238 0.1 mg/kg/day and chlormadinone acetate (CMA) 0.3 mg/kg/day p.o., respectively, for 5 months. In group 1, glandular hyperplasia of the prostate was clearly detected. In contrast, TZP-4238 (Group 2) or CMA (Group 3) produced marked atrophy of the glandular epithelium. In addition, a histopathological study showed that TZP-4238 or CMA medication for 5 months exerted no effect on the testes and the pituitary luteinizing hormone (LH) cells. Therefore, it is suggested that TZP-4238 (0.1 mg/kg) or CMA (0.3 mg/kg) causes regression of spontaneous canine BPH without any histopathological effects on the testes and pituitary LH cells. However, slightly decreased serum testosterone levels were found in TZP-4238-treated animals, due apparently to a direct and/or indirect effect on the testes. Thus, it is suggested that a marginal antigonadotrophic effect cannot be excluded. It is concluded that TZP-4238 is a potent anti-androgen for the treatment of spontaneous canine BPH, without any negative influence on the function of the testes and the pituitary LH cells.     

Twenty-six-Week carcinogenicity study of chloroform in CB6F1 rasH2-transgenic mice

The carcinogenic potential of chloroform was evaluated in a short-term carcinogenicity testing system using CB6F1 rasH2-Tg (rasH2-Tg) mice. Chloroform was administered to rasH2-Tg males at doses of 28, 90, or 140 mg/kg and rasH2-Tg females at 24, 90, or 240 mg/kg by oral gavage for 26 weeks. Wild-type (non-Tg) male and female mice received doses of 140 mg/kg and 240 mg/kg, respectively. N-methyl-N-nitrosourea was administered to rasH2-Tg mice by single intraperitoneal injection (75 mg/kg) as a positive control. In both the rasH2-Tg and non-Tg mice, there was no significant increase in the incidence of neoplastic lesions by chloroform treatment. The incidence of hepatocellular foci in the rasH2- and non-Tg females receiving 240 mg/kg was increased. Forestomach tumors and malignant tumors occurred in most of the rasH2-mice in the positive control group. Swelling or vacuolation of hepatocytes, a toxic change induced by chloroform, occurred in both the rasH2-Tg and non-Tg mice. It is concluded that chloroform, a putative human noncarcinogen, did not show evidence of carcinogenic potential in the present study using rasH2-Tg mice. This study suggests that the rasH2-Tg mouse model may not be appropriate for detecting nongenotoxic carcinogens. However, the sensitivity of rasH2-Tg mice to nongenotoxic carcinogens should be assessed with consideration of the results from the other ILSI-HESI project studies.