Isolation, characterization and structural organization of the gene and pseudogene for the dihydrolipoamide succinyltransferase component of the human 2-oxoglutarate dehydrogenase complex

In the present study, the dihydrolipoamide succinyltransferase gene of the 2-oxoglutarate dehydrogenase complex was isolated from a human genomic DNA library and its entire nucleotide sequence was determined. This gene was approximately 23 kbp in size with 15 exons and 14 introns. All of the donor and acceptor splice sites of this gene conformed to the GT/AG rule. A guanine residue 43 bases upstreams of the ATG initiating translation codon was the transcription initiation site of the human dihydrolipoamide succinyltransferase mRNA. Sequence analysis of the promoter-regulatory region showed the presence of a CAAT-box-like sequence but the presence of a TATA-box-like sequence was not evidenced. Also located in this region were sequences resembling glucocorticoid-responsive and cAMP-responsive elements, and an Sp1 binding site. No nucleotide sequence corresponding to the E3-binding and/or E1-binding domain was found in any region of the gene. Therefore, the exon coding for the E3-binding and/or E1-binding domain may have been lost from the gene during evolution. Moreover, a processed pseudogene of dihydrolipoamide succinyltransferase was isolated and sequenced. The nucleotide sequence of the pseudogene is 93% similar to the sequence of the human dihydrolipoamide succinyltransferase cDNA, but the pseudogene is not functional for base changes, deletions and insertions of the pseudogene. Southern-blot analysis showed the presence of a single copy of this gene and a single copy of a pseudogene in the human genome. In addition, a possible relationship between dihydrolipoamide succinyltransferase and familial Alzheimer's disease is discussed.

Cultured murine dermal cells can function like thymic nurse cells

We have established a dermal fibroblast-like stromal cell line, DFB-1, and a clone, 12E2, from epidermal sheets prepared from the skin of BALB/c mouse ears by trypsin digestion. They were suggested to be fibroblasts or myofibroblasts, as 1) they were polygonal or spindle-shaped under the phase-contrast microscope, 2) they did not possess any tonofilaments or desmosomes, and 3) they did not express any marker for bone marrow-derived cells or macrophages. Interestingly, these cells showed a unique phenomenon of "pseudo-emperiporesis," which was first recognized in the interaction between thymic nurse cells and thymocytes. Namely, two T-cell clones and one T-cell hybridoma migrated beneath the cytoplasmic projections of the fibroblast-like cutaneous stromal cells in culture. Furthermore, secretion of interleukin 7 by these cells was confirmed by bioassay using an IL-7-dependent cell line and by inhibition with anti-interleukin 7 antibody, and the expression of interleukin 7 mRNA was also demonstrated in these cells by a combination of reverse-transcriptase polymerase chain reaction and Southern blot analysis. These data strongly suggest the presence of unique stromal cells even in the skin, probably at the upper dermis, which can function like the nurse cells in the thymus. These stromal cells may play a crucial role in cutaneous immunophysiology.

Antimetastatic effects of synthetic peptides containing the core sequence of the type III connecting segment domain (IIICS) of fibronectin

The antimetastatic activities of synthetic peptides corresponding to fragments of the adhesion-related molecules, such as fibronectin and laminin, were examined. We prepared three peptides derived from the type III connecting segment domain (IIICS) of fibronectin: Glu-Ile-Leu-Asp-Val (EILDV), Glu-Ile-Leu-Asp-Val-Pro-Ser-Thr (EILDVPST), Arg-Glu-Asp-Val (REDV), and a laminin-related peptide, Tyr-Ile-Gly-Ser-Arg (YIGSR). Each peptide inhibited the experimental tumor metastasis of B16-BL6 melanoma, while EILDV had the strongest effect. The peptides conjugated with poly(ethylene glycol) (PEG) were more effective than the unmodified peptides in molar ratio terms. A mixture composed of PEG hybrids with EILDV, REDV and YIGSR significantly inhibited tumor metastasis.

Glial extracellular matrix modulates gamma-glutamyl transpeptidase activity in cultured bovine brain capillary and bovine aortic endothelial cells

Glial extracellular matrix (ECM) elevated gamma-glutamyl transpeptidase (gamma-GTP) activity in cultured bovine brain capillary and aortic endothelial cells (BBCEC, BAEC). In particular, the ECM of glial cells cultured with the conditioned medium of BAEC (BAEC CM) dramatically elevated gamma-GTP activity in BBCEC and BAEC. The ECM of glial cells cultured with BBCEC CM also had a marked effect. The ECM of 3T3 cells cultured with BAEC CM, and the ECM of glial cells cultured with 3T3 CM had no effect. Glial CM had no effect on gamma-GTP activity in BBCEC and BAEC. These findings indicate that gamma-GTP activity in endothelial cells (EC) is modulated by glial ECM, and that the factor of ECM that affects gamma-GTP activity in EC arises from the interaction between glial cells and EC.

Visualization of DNA double strand breaks in the gerbil hippocampal CA1 following transient ischemia

To clarify the relationship between delayed neuronal death and apoptosis, we made an attempt to detect DNA strand breaks in the gerbil hippocampal CA1 pyramidal neurons following transient ischemia by an in situ DNA double strand breaks staining. The condensed nuclei of neurons in CA1 were occasionally seen and positively stained 3 days after ischemia. The degenerating dark neurons with condensed nuclei in CA1 markedly increased in number and were clearly stained for DNA strand breaks 5 days after ischemia, whereas normal-looking nuclei remained unstained. No neurons were stained in other hippocampal subfields and dentate gyrus. The present study strongly indicates that the CA1 pyramidal neurons die through an apoptotic process.

Hemiballism with striatal hyperintensity on T1-weighted MRI in diabetic patients: a unique syndrome

We report 3 diabetic patients who developed hemiballism without involvement of the subthalamic nucleus. Each patient exhibited vigorous, flinging, ballistic involuntary movements in the extremities and slight facial grimacing involving one side of the body. Although diabetes was poorly controlled in all 3, each patient was nonketotic at the onset of hemiballism. Magnetic resonance imaging (MRI), in these patients showed abnormalities in the striatum contralateral to the hemiballism that were characterized by an increase in intensity on T1-weighted images and a slight decrease in intensity on T2-weighted images, and these changes persisted for more than 2 months. The striatal lesions are presumed to have developed following mild ischemia in the territory of the lateral striate branches of the middle cerebral artery. This combination of hemiballism and striatal lesions in diabetic patients may constitute a unique syndrome.

Signal transduction mediated by the reconstituted IL-2 receptor. Evidence for a cell type-specific function of IL-2 receptor beta-chain

The binding of IL-2 to its specific receptor (IL-2R) triggers various cellular events including the induction of nuclear proto-oncogenes (c-fos, c-jun and c-myc genes) and the proliferation of hemopoietic cells. In the present study, we have established NIH 3T3 fibroblasts in which the three IL-2R subunits, the alpha-chain (IL-2R alpha), the beta-chain (IL-2R beta), and the gamma-chain (IL-2R gamma), are constitutively expressed. The resulting cell lines express high affinity IL-2R on their cell surface at levels comparable with those of IL-2-responsive lymphoid cells. We observed that the high affinity IL-2R in NIH 3T3 fibroblasts can mediate the IL-2-stimulated tyrosine phosphorylation of p42/p44 (mitogen-activated protein kinase) and the induction of the c-fos, c-jun and c-myc genes. In NIH 3T3 fibroblasts the high affinity IL-2R bearing a deletion of a region rich in acidic amino acids (the "acidic" region) in the IL-2R beta-chain failed to induce the tyrosine phosphorylation of MAP kinase as well as the expression of the all three nuclear proto-oncogenes. On the other hand, our previous studies had demonstrated that the high affinity IL-2R bearing the same mutant IL-2R beta-chain retained the ability to induce c-myc gene in response to IL-2 in a murine IL-3-dependent pro-B cell line, BAF/B03. Hence, these results reveal the underlying complexity of signal transduction among different cell types. The inability of the reconstituted high affinity receptor to mediate the IL-2-induced proliferation of NIH 3T3 fibroblasts suggests that induction of the three nuclear proto-oncogenes and the tyrosine phosphorylation of mitogen-activated protein kinase in NIH 3T3 fibroblasts are not sufficient to induce cellular proliferation.

Signal transduction mediated by the reconstituted IL-2 receptor. Evidence for a cell type-specific function of IL-2 receptor beta-chain

The binding of IL-2 to its specific receptor (IL-2R) triggers various cellular events including the induction of nuclear proto-oncogenes (c-fos, c-jun and c-myc genes) and the proliferation of hemopoietic cells. In the present study, we have established NIH 3T3 fibroblasts in which the three IL-2R subunits, the alpha-chain (IL-2R alpha), the beta-chain (IL-2R beta), and the gamma-chain (IL-2R gamma), are constitutively expressed. The resulting cell lines express high affinity IL-2R on their cell surface at levels comparable with those of IL-2-responsive lymphoid cells. We observed that the high affinity IL-2R in NIH 3T3 fibroblasts can mediate the IL-2-stimulated tyrosine phosphorylation of p42/p44 (mitogen-activated protein kinase) and the induction of the c-fos, c-jun and c-myc genes. In NIH 3T3 fibroblasts the high affinity IL-2R bearing a deletion of a region rich in acidic amino acids (the "acidic" region) in the IL-2R beta-chain failed to induce the tyrosine phosphorylation of MAP kinase as well as the expression of the all three nuclear proto-oncogenes. On the other hand, our previous studies had demonstrated that the high affinity IL-2R bearing the same mutant IL-2R beta-chain retained the ability to induce c-myc gene in response to IL-2 in a murine IL-3-dependent pro-B cell line, BAF/B03. Hence, these results reveal the underlying complexity of signal transduction among different cell types. The inability of the reconstituted high affinity receptor to mediate the IL-2-induced proliferation of NIH 3T3 fibroblasts suggests that induction of the three nuclear proto-oncogenes and the tyrosine phosphorylation of mitogen-activated protein kinase in NIH 3T3 fibroblasts are not sufficient to induce cellular proliferation.

Production of human PTH(1-34) via a recombinant DNA technique

The production of hPTH(1-34) by site specific chemical cleavage of [Cys35]hPTH(1-84) obtained by a biotechnology technique is described. The amino-peptide bond of S-cyanylated cysteine residues in peptides or proteins is specifically cleaved by exposure to an alkaline solution (Stark, G. R. (1977) Methods Enzymol, 47, 129-132). However, when applying this method to [Cys35]hPTH(1-84), we observed many by-products. Formation of these by-products was suppressed using a short reaction in 0.03N NaOH containing 6M urea at low temperature, and hPTH(1-34) was specifically produced. The product was indistinguishable from standard hPTH(1-34) with respect to chemical and biological characterization.

Remarkable elevation of interleukin 6 and interleukin 8 levels in the bone marrow serum of patients with rheumatoid arthritis

OBJECTIVE

Characteristic cellular changes have previously been reported in the bone marrow of patients with rheumatoid arthritis (RA). We investigated the levels of various cytokines in RA bone marrow.

METHODS

We studied 25 patients with RA (22 women and 3 men) and 10 trauma patients (7 women and 3 men) as non-RA controls. Twelve kinds of cytokines [interleukin (IL)-1 alpha, IL-1 beta, IL-2, IL-3, IL-4, IL-6, IL-7, IL-8, granulocyte colony stimulating factor, granulocyte/macrophage colony stimulating factor, tumor necrosis factor (TNF)-alpha, and TNF-beta] were assayed by ELISA in iliac bone marrow serum (BMS), tibial BMS, and peripheral blood serum.

RESULTS

Markedly elevated levels of IL-6 and IL-8 were detected in iliac BMS, and much lower levels were found in tibial bone marrow and peripheral blood serum. The levels of IL-6 and IL-8 in iliac BMS showed a close relationship to the extent of synovial proliferation.

CONCLUSION

Iliac bone marrow may be an important site for the production or accumulation of IL-6 and IL-8 in RA, and these cytokines may influence synovial proliferation in patients with polyarthritis.

Human parathyroid hormone: efficient synthesis in Escherichia coli using a synthetic gene, purification and characterization

Human parathyroid hormone is a peptide hormone consisting of 84 amino acid residues. Production of small proteins by direct expression in Escherichia coli is often unsuccessful owing to susceptibility of the mRNA and/or the product to endogenous enzymes. In this study, direct expression of the hormone at an excellent level (over 100 mg/L) has been achieved by using a suitably designed synthetic gene under the control of the T7 promoter. The protein produced in bacteria was extracted and easily purified in a good yield of 27 mg/L. The purified product was physico-chemically identified as intact human parathyroid hormone from the results of amino acid analysis, N-terminal sequencing, and peptide mapping using fast atom bombardment mass spectrometry. In biological assays the purified product stimulated adenylate cyclase in vitro, promoted bone growth and increased the serum osteocalcin in rats to the same extent as the authentic hormone.

Pharmacokinetics and safety of BO-2727, a new injectable 1-beta-methyl carbapenem antibiotic, and its effect on the faecal microflora in healthy male volunteers

The safety and pharmacokinetics of BO-2727, a new injectable 1-beta-methyl carbapenem antibiotic, and its effect on the faecal microflora were evaluated in single- and multiple-dose studies involving twenty-four healthy male adult volunteers following a preliminary safety evaluation of 25, 50 and 125 mg iv doses in six volunteers. BO-2727 was administered by iv infusion over 30 min. There was a good correlation between BO-2727 concentrations assayed by HPLC and a microbiological method; the HPLC results were used in the pharmacokinetic analysis. The single-dose study indicated that plasma concentration versus time curves at doses of 250, 500 and 1000 mg were well described by a two-compartment open model. The mean (+/- S.D.) elimination half-life ranged from 1.41 +/- 0.21 h to 1.54 +/- 0.10 h, and the peak plasma concentrations (Cmax) and the area under the plasma concentration versus time curves increased linearly with the dose. The mean urinary recoveries within the first 24 h were 70.63 +/- 5.24% to 77.38 +/- 4.55% of the dose. The highest concentration of BO-2727 in saliva was 0.72 mg/L which was reached 1 h after the start of the 1000 mg infusion and accounted for approximately 1% of the Cmax. No BO-2727 was found in faecal samples collected 24 and 48 h after a single 1000 mg dose. In the multiple-dose study, BO-2727 500 mg bd was administered for 4.5 days. There were no obvious differences in plasma concentrations and urinary recoveries between the single- and multiple-dose regimens. BO-2727 did not accumulate as determined by plasma concentrations and urinary recoveries. No marked changes in the aerobic and anaerobic faecal microflora were observed during multiple-dose administration. There were no significant adverse reactions, and likewise no abnormalities in physical and laboratory examinations that were definitely related to the drug.

[Successful collection of peripheral blood stem cells mobilized by high-dose etoposide for patients with chemotherapy-resistant and/or poor prognostic testicular cancer]

Clinical effects of peripheral blood stem cell autotransplantation (PBSCT) after ultra high-dose chemotherapy were evaluated in patients with chemotherapy-resistant and/or poor prognostic testicular cancer. Four patients with testicular cancer, who had high-risk malignancy, were treated with high-dose etoposide (500 mg/m2 x 4 days) in order to collect peripheral blood stem cells. After the administration of high-dose etoposide, rG-CSF (250 micrograms/body) was administered from nadir state. Blood mononuclear cells were collected using a Fenwall CS-3000 blood cell separator. Fractions enriched for stem cells were obtained by discontinuous Percoll gradient centrifugation and were stored in liquid nitrogen using patient's sera and DMSO. The mean number of peripheral blood granulocyte-macrophage-colony-forming units (CFU-GM) collected by one apheresis was 22.3 x 10(5)/kg body weight. In addition, CFU-GM more than 2.0 x 10(5)/kg body weight could be collected in each apheresis, which was though to be sufficient dosis to perform PBSCT in safe, based upon our previous studies. All the patients were treated by a combination of cisplatin (20 mg/m2 x 5 days), etoposide (100 mg/m2 x 5 days) and bleomycin (15 mg x 3 days). Three patients responded to BEP therapy and obtained a CR, however, remaining 1 patient failed to achieve CR, who was later treated by ultrahigh-dose chemotherapy including carboplatin (200 mg/m2 x 4 days), etoposide (250 mg/m2 x 4 days) and cyclophosphamide (50 mg/kg x 2 days) followed by PBSCT. He responded to this therapy and obtained a CR for 10 months. The results suggested the method was promising for patients with chemotherapy-resistant and/or poor prognostic testicular cancer.

[Clinical evaluation of M-VAC (methotrexate, vinblastine, adriamycin and cisplatin) chemotherapy for advanced urothelial cancer]

M-VAC (methotrexate, vinblastine, adriamycin and cisplatin) chemotherapy was performed on 27 patients with advanced urothelial cancer. The patients included 20 with bladder cancer, 4 with upper urinary tract cancer and 3 with both lesions. Complete response (CR) was observed in 2 (7.4 +/- 9.9%) patients and partial response (PR) in 10 (37.0 +/- 18.2%) patients after the treatment, i.e., the overall objective response rate was 44.4 +/- 18.7%. The rate of relapse or recurrence in the patients with CR and PR was 100% and 90.0%, respectively. The mean duration of the response was 18.5 +/- 13.4 months and 10.7 +/- 10.9 months for CR and PR, respectively. The overall survival rate after one year was 30.2%. Bone marrow suppression was the most serious side effect. The white blood cell count became below 1,000/microliters in 10 patients (36.7%). Among them, 4 patients suffered from sepsis. In conclusion, M-VAC chemotherapy was effective for induction therapy against advanced urothelial cancer, although the effective duration was short. Further maintenance therapy should be established.

[Clinical evaluation on renal pelvic and ureteral tumors]

We report 82 patients with renal pelvic and ureteral tumors admitted to Kyoto Prefectural University of Medicine, Kyoto Second Red Cross Hospital and Shakai-Hoken Kyoto Hospital between January, 1981 and December, 1991. Sixty two were males and 24 were females, and they were between 47 and 93 years old (average: 68.2 years). The tumor occurred on the right side in 34 patients, on the left side in 51 patients and on both sides in one patient. There were 43 renal pelvic tumors, 37 ureteral tumors and 6 renal pelvic with ureteral tumors. The most frequent symptom was macrohematuria, which was seen in 54 patients (62.8%). Urinary cytology was performed in 76 patients and a positive result was obtained in 44 patients (57.9%). We performed surgical treatment on 71 patients. The most frequently adopted method was total nephroureterectomy with partial cystectomy which was performed on 51 patients (71.8%). Of the 73 specimens diagnosed histopathologically, 71 specimens were transitional cell carcinoma (TCC), one was a squamous cell carcinoma (SCC) and one was a mixed type of TCC and adenocarcinoma. As to grading, 6 specimens were G1, 28 G2, 38 G3 and one GX. As to staging, 8 specimens were pTa, 17 pT1, 21 pT2, 18 pT3, 8 pT4 and one pTX. The overall survival rate (by Kaplan-Meier's method) at 3 and 5 years was 47.0% and 39.5%, respectively. The patients with high grade tumors and those who had ureter preservation, the survival rate was lower than in the other patients.

Localization of preganglionic neurons of the accessory ciliary ganglion in the midbrain: HRP and WGA-HRP studies in the cat

Localization of preganglionic neurons of the accessory ciliary ganglion (ACG), including ectopic intraocular ganglion cells, was investigated in the cat with the aid of horseradish peroxidase (HRP) and HRP-conjugated wheat germ agglutinin (WGA-HRP) methods. When HRP or WGA-HRP was injected into the anterior and posterior chambers of the eye, no retrogradely labeled cells were found in the visceral oculomotor nuclei, although most neurons of the ACG and the main ciliary ganglion (CG) were intensely labeled. When a microsyringe needle was inserted into the ciliary body, the tracer diffused into the suprachoroid lamina and the intraocular ganglion cells, and a small number of labeled neurons appeared in the midplane between each side of the somatic oculomotor nuclei. After injection into the ACG, many labeled neurons were observed in the anteromedian nucleus, Edinger-Westphal nucleus, and midplane between the somatic oculomotor nuclei, their ventral continuations of the ventral tegmental area, and the periaqueductal gray. HRP/WGA-HRP injection into the CG labeled cells in all these areas and in the lateral border zones of the anteromedian, Edinger-Westphal and somatic oculomotor nuclei, and their ventral continuations of the ventral tegmental area. These findings indicate that the visceral oculomotor neurons which project to the ACG tend to be located more medially than those to the CG.

[Ultra high-dose chemotherapy with peripheral blood stem cell autotransplantation for refractory testicular cancer]

This is a report of 45-year-old man with advanced nonseminomatous germ cell tumor (stage IIIB2: embryonal carcinoma, yolk sac tumor, seminoma), who had relapse after PVB (cisplatin, vinblastine, bleomycin) chemotherapy. Peripheral blood stem cells (PBSCs) were taken by two consecutive apheresis using a CS-3000 blood separator after high-dose chemotherapy of cytarabine and mitoxantrone. In total, 6.4 x 10(5)/kg of granulocytic cells (CFU-GM) was collected. He was treated with ultra high-dose chemotherapy consisting of carboplatin (800 mg/m2), etoposide (1,000 mg/m2) and cyclophosphamide (100 mg/kg) from day 1, followed by peripheral blood stem cell autotransplantation (PBSCT) on day 9. We transfused 2.4 x 10(5)/kg CFU-GM, which was enough number of stem cells for safe PBSCT. No serious side effects or complications were encountered. The patient achieved partial remission for more than two months. However, he died of respiratory dysfunction caused by metastatic lung cancer 5 months later. It was thought that ultra high-dose chemotherapy with PBSCT might be a new therapy for refractory testicular cancer.

Regulation of hepatic level of fatty-acid-binding protein by hormones and clofibric acid in the rat

Regulation of the hepatic level of fatty-acid-binding protein (FABP) by hormones and p-chlorophenoxyisobutyric acid (clofibric acid) was studied. The hepatic level of FABP, measured as the oleic acid-binding capacity of the cytosolic FABP fraction, was decreased in streptozotocin-diabetic rats. The level of FABP was markedly increased in adrenalectomized rats, and the elevation was prevented by the administration of dexamethasone. Hypothyroidism decreased the level of FABP and hyperthyroidism increased it. A high correlation between the incorporation of [14C]oleic acid in vivo into hepatic triacylglycerol and the level of FABP was found for normal, diabetic and adrenalectomized rats. The level of FABP was increased by administration of clofibric acid to rats in any altered hormonal states, as was microsomal 1-acylglycerophosphocholine (1-acyl-GPC) acyltransferase, a peroxisome-proliferator-responsive parameter. These results suggest that the hepatic level of FABP is under regulation by multiple hormones and that clofibric acid induces FABP and 1-acyl-GPC acyltransferase by a mechanism which may be distinct from that by which hormones regulate the level of FABP.

Structure of the L-histidine decarboxylase gene

Two species of L-histidine decarboxylase (HDC) mRNA were found in the KU-812-F basophilic cell line, but only the 2.4-kilobase (kb) one encodes the functional HDC (Mamune-Sato, R., Yamauchi, K., Tanno, Y., Ohkawara, Y., Ohtsu, H., Katayose, D., Maeyama, K., Watanabe, T., Shibahara, S., and Takishima, T. (1992) Eur. J. Biochem. 209, 533-539). The 3.4-kb one encodes a truncated HDC protein and is also found in human leukemia-derived cell lines HEL and KCL-22. To clarify the mechanisms that regulate transcription of the HDC gene and generate the two species of mRNA, we have isolated genomic DNA clones coding for the HDC from human genomic libraries. Structural analysis of the isolated clones revealed that the human HDC gene is composed of 12 exons spanning approximately 24 kb. Genomic DNA blot analysis suggested that HDC is encoded by a single copy gene. The structural analysis also demonstrated that the heterogeneity of the HDC mRNA is caused by an insertion of the seventh intron sequence and alternative use of the splicing acceptor site at the 12th exon. The transcription start site of the HDC gene and the nucleotide sequences of the promoter and first exon regions were determined. We found a TATA-like sequence, a GC box, four CACC boxes, four GATA consensus sequences, and six leader-binding protein-1 binding motifs in the promoter region of the HDC gene.

Chemical modification of natural human tumor necrosis factor-alpha with polyethylene glycol increases its anti-tumor potency

Natural human tumor necrosis factor-alpha (TNF-alpha) was chemically modified with an active ester of monomethoxy polyethylene glycol (PEG). The molecular weight of PEG-modified TNF-alpha depended on the reaction time as well as the initial molar ratio of PEG to TNF-alpha. The specific activity of modified TNF-alpha was gradually reduced with increase in the degree of PEG-modification, but the plasma half-life of TNF-alpha was increased by up to 40-fold. Modified TNF-alpha showed approximately 100 times greater anti-tumor potency than unmodified TNF-alpha. Covalent attachment of PEG to TNF-alpha thus increased the bioavailability of TNF-alpha, and may facilitate its potential therapeutic use.

Roles of neutrophil elastase and superoxide anion in leukotriene B4-induced lung injury in rabbit

The effects of a competitive neutrophil elastase (NE) inhibitor, ONO-5046, and a recombinant human superoxide dismutase on leukotriene B4 (LTB4)-induced polymorphonuclear leukocyte (PMN)-mediated increase in microvascular permeability in isolated non-blood-perfused rabbit lungs were studied. Pulmonary microvascular permeability and lung edema were evaluated by use of the fluid filtration coefficient (Kf) and the wet-to-dry lung weight ratio (W/D), respectively. Pulmonary capillary pressure was estimated by the double occlusion technique. NE activity in the perfusate was determined using a spectrophotometric method. The PMNs (2-3 x 10(8) cells) were added into the perfusate in all groups of lungs. Injection of LTB4 (5 micrograms) increased Kf and W/D without affecting pulmonary arterial or capillary pressure. The LTB4-induced lung injury was closely associated with the increase in NE activity in the perfusate. Infusion of ONO-5046 (1 or 10 mg.kg-1 x h-1) inhibited the LTB4-induced increases in Kf, W/D, and perfusate NE activity in a dose-dependent fashion. Infusion of recombinant human superoxide dismutase (80,000 U.kg-1 x h-1) attenuated the LTB4-induced increases in Kf and W/D, although it did not influence the elevation of perfusate NE activity induced by LTB4. These results suggest that both NE and superoxide anion play important roles in the LTB4-induced PMN-mediated increase in pulmonary microvascular permeability.

Infection by Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans, and antibody responses at different ages in humans

This study examined the serum IgG and IgM responses against Porphyromonas gingivalis and 3 serotypes of Actinobacillus actinomycetemcomitans, and the correlations of these responses with age and homologous infection. A total of 90 individuals were included in this study: 40 subjects with gingivitis, 40 periodontally healthy subjects, and 10 adult periodontitis subjects. The subjects in the gingivitis and periodontally healthy groups were divided into 4 stages based on their physiological age: early childhood, school age, puberty, and adult. In the gingivitis group, there was a positive correlation between increase in age and increase in serum IgG antibody levels against P. gingivalis until puberty. However, no statistically significant difference was found between the puberty stage and the adult stage. The average level of IgG antibodies against A. actinomycetemcomitans in the school age gingivitis group was significantly higher than that in the early childhood gingivitis group for all serotypes (p < 0.01). In serotype c, IgG antibody levels in the school age gingivitis group were significantly higher than in the early childhood gingivitis group or the adult gingivitis group (p < 0.01). With both P. gingivalis and A. actinomycetemcomitans, positive correlations between elevated IgG level and infections by these microorganisms were found in the puberty gingivitis and adult periodontitis groups.

2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (AF-2) is a weak in vivo clastogen as revealed by the micronucleus assay

The in vivo clastogenicity of 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (AF-2) was examined in the micronucleus test using peripheral blood from three mouse strains (ICR, CD-1, and MS/Ae) and bone marrow from one rat strain (Sprague-Dawley). Doses up to the maximum tolerated were tested. The chemical was given once, twice, thrice, or four times via either the i.p. or p.o. route. Under some conditions, ICR and CD-1 mice showed an increased frequency of micronucleated reticulocytes, but definite conclusions were difficult to draw because the increases were very slight. MS/Ae mice showed a markedly elevated micronucleated reticulocyte frequency after the double and triple ip treatments. Rats showed a slightly but statistically significantly increased frequency of micronucleated polychromatic erythrocytes after double i.p. treatments. These results indicate that AF-2 is a weak in vivo clastogen.