Gene polymorphism and frequencies of the NPC1L1 gene (rs2072183, rs217434 and rs217428) in Japanese patients with dyslipidemia

WHAT IS KNOWN AND OBJECTIVE

Niemann-Pick C1-Like 1 (NPC1L1) plays a pivotal role in intestinal cholesterol absorption. Ezetimibe is known as an inhibitor for NPC1L1 and decreases concentration of low-density lipoprotein cholesterol (LDL-C) in blood. Responses of the decrease of serum LDL-C levels to ezetimibe have been reported to be different among NPC1L1 variants. However, there are still limited data concerning the genetic variation in the NPC1L1 gene, specifically, in Japanese patients with dyslipidemia. The purpose of this study is to elucidate genotype and allele frequencies of the NPC1L1 gene in Japanese patients with dyslipidemia.

METHODS

Written informed consent was obtained from all participants. All patients were administered ezetimibe at the dose of 10 mg for once a day either alone or coadministered with statins. Patient's data were retrospectively obtained from their medical records. Genomic DNA was extracted from whole blood samples and analysed three NPC1L1 SNPs (rs2072183, rs217428 and rs217434) by the direct sequencing method.

RESULTS AND DISCUSSION

We found that there is a significant difference of genotype frequencies between healthy Japanese and dyslipidemic subjects in rs2072183. No significant differences were observed in rs217428 and rs217434; however, comparison of our data with literature reports suggests that there are significant differences in the frequencies of rs217428 and rs217434 between Canadian and Japanese dyslipidemic patients.

WHAT IS NEW AND CONCLUSION

Our study is the first report concerning the genotype and allele frequencies of the gene coding for NPC1L1 in Japanese patients with dyslipidemia. The most notable result was to demonstrate that there exists a significant difference in rs2072183 variant between healthy Japanese and dyslipidemic subjects and also found that there exists genetic variation of rs2072183 between Japanese and Canadian patients with dyslipidemia. Our results are expected to facilitate research in the proper use of ezetimibe-based mono- or combination therapies. Further studies will be required to evaluate the effects of rs2072183 on the efficacy of LDL cholesterol reduction by ezetimibe.

Clinical and endoscopic characteristics of acute haemorrhagic rectal ulcer, and endoscopic haemostatic treatment: a retrospective study of 95 patients

AIM

Acute haemorrhagic rectal ulcer (AHRU) is characterized by sudden onset of painless and massive rectal bleeding in elderly bedridden patients who have serious illness. Endoscopic diagnosis and management of AHRU is, however, still controversial. We retrospectively investigated 95 AHRU patients to elucidate the clinical characteristics, endoscopic findings and haemostatic strategies.

METHOD

Between January 1999 and March 2007, 95 patients were diagnosed with AHRU in our hospital. Medical records and colonoscopy files were reviewed. Clinical features, colonoscopic findings, haemostatic treatment and outcome of the patients were evaluated.

RESULTS

Eighty per cent of the patients were bedridden at the onset. The most frequent underlying disorder was cerebrovascular disease (36.8%). Hypoalbuminaemia (< 3.5 g/dl) was seen in 92.6% of the patients. Endoscopic findings of AHRU were classified as circumferential ulcer (41.1%), linear or nearly round small ulcer(s) (44.2%), circumferential and small ulcer(s) (7.4%) and Dieulafoy-like ulcer (7.4%). Primary endoscopic haemostatic treatment was performed in 45.3% of cases. Recurrent bleeding occurred in 24.2% of patients. Permanent haemostasis was achieved by secondary endoscopic treatment in 82.6% of re-bleeding patients.

CONCLUSION

Understanding the typical clinical and endoscopic findings and careful endoscopic examination are important for the accurate diagnosis of AHRU, and endoscopic haemostatic therapy may be effective for bleeding patients.

Multidrug resistant Mycobacterium leprae from patients with leprosy

Sequences of the folP1, rpoB, and gyrA genes were analyzed for 88 isolates of Mycobacterium leprae from leprosy patients in Japan, Haiti, Indonesia, Pakistan, and the Philippines. Thirteen isolates (14.8%) showed representative mutations in more than two genes, suggesting the emergence of multidrug-resistant M. leprae.

Simultaneous detection of Mycobacterium leprae and its susceptibility to dapsone using DNA heteroduplex analysis

Currently recommended control measures for treating leprosy with multidrug therapy should control the spread of drug-resistant strains; however, dapsone (DDS) resistance continues to be reported. Comprehensive estimates of drug-resistant leprosy are difficult to obtain due to the cumbersome nature of the conventional drug susceptibility testing method using mouse footpad inoculation, which requires at least 6 months to obtain results. Recently, it has been determined that DDS-resistant strains contain missense mutations in codon 53 or 55 of the folP1 gene of Mycobacterium leprae, and definitive evidence linking these mutations with DDS resistance in M. leprae has been obtained. Based on these mutations, a heteroduplex DDS M. leprae (HD-DDS-ML) assay was developed for the simultaneous detection of M. leprae and of its susceptibility to DDS. The assay relies on the PCR amplification of an M. leprae-specific 231-bp fragment of folP1 containing codons 53 and 55. The PCR products are allowed to anneal to a universal heteroduplex generator, and the separation of the resultant DNA duplexes is accomplished by polyacrylamide gel electrophoresis. M. leprae was detected in crude cell lysates of skin biopsy specimen homogenates from eight leprosy patients and from M. leprae-infected mouse or armadillo tissues infected with 14 separate strains using the HD-DDS-ML assay. The assay was specific for M. leprae in a comparison with results obtained from 14 species of mycobacteria other than M. leprae and four bacterial species known to colonize human skin. The HD-DDS-ML assay detected as few as 100 M. leprae organisms present in homogenates of human skin and demonstrated a 93% correlation with DDS susceptibility as determined by both DNA sequencing of folP1 and mouse footpad susceptibility testing. The HD-DDS-ML assay provides a new tool for the simultaneous detection of M. leprae and of its susceptibility to DDS from a single specimen. The assay should prove useful for drug resistance surveillance in leprosy control programs when combined with similar molecular tests developed for other drug resistance markers.

Pro- and anti-inflammatory gene expression in the murine small intestine and liver after chronic exposure to alcohol

BACKGROUND

Endotoxin has been proposed to play a primary role in ALD, by initiating an inflammatory cascade within the liver. Although the source of these cytokines has been presumed to be circulating monocytes or tissue macrophages, ethanol-induced, nonhepatic sources of soluble mediators recently have been identified. One potential, but not clearly defined, extrahepatic source of cytokines in ALD is the intestine. In the current study, we hypothesized that alcohol would alter cytokine expression within the small intestine of mice exposed to ethanol and that LPS would alter levels of cytokine expression even more dramatically.

METHODS

Mice were fed a modified Lieber-DeCarli liquid ethanol or control diet for up to 14 days prior to injecting either saline or LPS. Plasma alanine aminotransferase (ALT) and cytokine levels, histology, and RT-PCR of pro- and anti-inflammatory cytokine gene expression were determined from distal ileum and liver samples. Translocation of intestinal bacterial flora also was assessed.

RESULTS

Ethanol exposure upregulated basal gene expression of IL-1 beta, TNF-alpha, IL-6, and iNOS in the distal ileum, but similar effects of ethanol on the liver were not observed. In contrast, LPS challenge of ethanol-exposed mice increased intestinal gene expression of some cytokines, but decreased expression of others. These effects were not associated with bacterial translocation. Also, ethanol alone induced a modest increase in both ICAM-1 and TLR4 mRNA expression in the intestine, but expression of both molecules was inhibited in mice that received both ethanol and LPS. Finally, whereas basal levels of hepatic IL-11 mRNA were not elevated by exposure to ethanol, intestinal IL-11 mRNA levels were increased more than 100-fold.

CONCLUSIONS

These studies are the first to show that ethanol affects cytokine gene expression in the ileum and identifies the ileum as a potential target for ethanol effects. In addition, our results suggest that IL-11 expression may be enhanced in the intestine to help repair or protect this organ from alcohol-induced damage. Collectively, these studies suggest that both pro- and anti-inflammatory soluble mediators in the intestine maintain and exacerbate the local hepatic response to ethanol.

Detection of Mycobacterium leprae by Polymerase Chain Reaction

The improved procedure based on Polymerase Chain Reaction (PCR) for detection of M. leprae has been developed. The sensitivity and specificity of this method were tested using different concentration of genomic DNA of M. leprae Thai 53 and genomic DNAs from mycobacterial species and related microorganisms respectively. Application of this method to biopsy samples obtained from Bangladesh was conducted and detected M. leprae DNA in 7 of the 10 clinical specimens. Acid fast bacilli were not detected in four of the seven positive cases under the microscopic observation. It was concluded that this method was sensitive and specific for detection of M. leprae in clinical specimens and also simple to detect in only one step of PCR.

A Mycobacterium leprae isolate resistant to dapsone, rifampin, ofloxacin and sparfloxacin

Mycobacterium leprae were isolated from a Japanese patient, and susceptibility to antileprosy drugs was examined by the mouse foot pad method. The isolate was susceptible to clofazimine and clarithromycin, and resistant to dapsone, rifampin, ofloxacin and sparfloxacin. Mutations were identified in the genes associated with resistance to these drugs. The risk of the emergence of leprosy with multidrug resistance is emphasized.

Comparison of polymerase chain reaction, immunohistochemistry and conventional histopathology in the diagnosis of early leprosy in Sichuan Province of China

46 formalin-fixed, paraffin-embedded skin biopsy specimens, which were clinically suspected or diagnosed as early leprosy, were retrieved from the files of Sichuan, China from 1997 to 1999. All of them were examined by polymerase chain reaction (PCR) using the primers amplifying the 130 base-pair fragment of the gene from the 16S ribosomal RNA of Mycobacterium leprae, hematoxylin and eosin (H&E) staining, modified Fite-Faraco technique for M. leprae and immunostaining with the antiserum against the PGL-1, LAM-B, S-100 protein using ABC method. PCR was positive for 27 (58.7%) of 46 specimens. In 13 (28.3%) among them, only PCR signals were positive for M. leprae and all other test were negative. AFB was positive for 7 (15.2%) of 46, PGL-1 was positive for 17 (36.9%) of 46, LAM-B was positive for 10 (21.7%) of 46. Early epithelioid cells granuloma was detected in 4 (8.7%) patients (TT 3, BT 1), macrophage granuloma was detected in 1 (2.2%) patient (BL), S-100 protein staining showed early nerve granuloma for 4 (8.7%) of 46, peripheral nerve inflammatory infiltration for 11 (23.9%) of 46. Comparison PCR with other method showed statistically significant difference. PCR have an advantage over microscopic examination in detecting M. leprae in biopsy specimens negative for acid-fast bacilli.

Molecular basis of clarithromycin-resistance in Mycobacterium avium intracellulare complex

Nucleotide sequences of domain V and domain II regions of the 23S rRNA gene were determined in both in vitro-made mutants and clinical isolates of Mycobacterium avium and M. intracellulare conferring clarithromycin-resistance. All laboratory-made mutants showed high level resistance to clarithromycin (> 150 micrograms ml-1) and mutation at position 2058 (cognate with Escherichia coli base) in domain V region. In the clinical isolates, while the susceptible ones had no mutation in domain V, the resistant strains showed mutation at 2058 or 2059. Six isolates with low level of resistance exhibited no mutation in domain V. All strains tested had no mutation in domain II region. These results suggested that most of the resistance arose from the mutation in domain V of the 23S rRNA gene, but other unknown mechanisms evidently exist in mycobacteria.

Mycobacterium leprae typing by genomic diversity and global distribution of genotypes

The genetic diversity and related global distribution of 51 Mycobacterium leprae isolates were studied. Isolates were obtained from leprosy patients from 12 geographically distinct regions of the world and two were obtained from nonhuman sources. Polymerase chain reaction (PCR) followed by DNA sequencing was performed targeting the rpoT gene of M. leprae. Isolates were classified into two groups based on the number of tandem repeats composed of 6 base pairs in the rpoT gene. Isolates from Japan (except Okinawa) and Korea belonged to one group, while those from Southeast Asian countries, Brazil, Haiti and Okinawa in Japan belonged to a second genotype. M. leprae obtained from two nonhuman sources (an armadillo and a mangabey monkey) revealed the latter genotype. These results demonstrate the genetic diversity of M. leprae and the related genotype-specific distribution in the world.

Diaminodiphenylsulfone resistance of Mycobacterium leprae due to mutations in the dihydropteroate synthase gene

The nucleotide sequence analysis of the dihydropteroate synthase (DHPS) gene of six diaminodiphenylsulfone-resistant Mycobacterium leprae strains revealed that the mutation was limited at highly conserved amino acid residues 53 or 55. Though the mutation at amino acid residue 55 or its homologous site has been reported in other bacteria, the mutation at residue 53 is the first case in bacteria. This is the first paper which links the mutations in DHPS and sulfonamide resistance in M. leprae. This finding is medically and socially relevant, since leprosy is still a big problem in certain regions.

Comparison of two dentin adhesives to primary vs. permanent bovine dentin

The purpose of this study was to compare the shear bond strengths of two adhesive systems to the primary and permanent dentin. Labial surfaces of extracted and frozen bovine mandibular primary incisors and permanent incisors were ground with #600 grit SiC paper to expose dentin. Bisco Dental Products All Bond 2 (Group AB2) or Sunmedical Co. Superbond D Liner (Group SDL) tooth surface conditioner and adhesive were applied and bonded with resin composite. A shear bond strength (SBS) test was performed and the data were analyzed by an ANOVA (P < 0.05). After the SBS test, the test surfaces of the dentin and the resin were observed using SEM. SBS on the primary dentin were significantly higher than those on the permanent dentin, both in the nonthermal cycled groups and the thermal cycled groups with the exception of the thermal cycled group of Group SDL. In the thermal cycled group of Group SDL, there was no significant difference between SBS on the primary dentin and SBS on the permanent dentin. Bond strengths on the primary dentin were found to be significantly higher than those on the permanent dentin, when using All Bond 2 or Superbond D Liner adhesive systems.

Pathological investigation of armadillos infected with Mycobacterium leprae

An infection experiment with M. leprae was carried out using 20 nine-banded armadillos. As a result, the development of leprous lesions and a marked multiplication of AFB were confirmed in a high rate of 13 out of 15 cases (86.8%) in the inoculated groups. These changes were found to be progressing at post mortem of one case even with the shortest life period for 7.5 months and were very serious in one case with the longest life period for 33 months, suggesting the continuation of symptoms, though it is an expression neglecting the individual difference in susceptibility to leprosy. Among infected viscera with AFB, the most conspicuous lesions were found in the liver and spleen. The developed lesions were found in the lung, stomach and kidney which had been never seen in HD in human cases, and so, which may characterize armadillos' leprosy. The change in the peripheral nerve was not so severe when compared with that in HD in human cases. This difference will remain as a future pathological problem to be solved.

Nucleotide sequence of the Mycobacterium leprae katG region

Synthetic oligonucleotide primers based on the DNA sequence data of the Escherichia coli, Mycobacterium tuberculosis, and Mycobacterium intracellulare katG genes encoding the heme-containing enzyme catalase-peroxidase were used to amplify and analyze the Mycobacterium leprae katG region by PCR. A 1.6-kb DNA fragment, which hybridized to an M. tuberculosis katG probe, was obtained from an M. leprae DNA template. Southern hybridization analysis with a probe derived from the PCR-amplified fragment showed that the M. leprae chromosome contains only one copy of the putative katG sequence in a 3.4-kb EcoRI-BamHI DNA segment. Although the nucleotide sequence of the katG region of M. leprae was approximately 70% identical to that of the M. tuberculosis katG gene, no open reading frame encoding a catalase-peroxidase was detectable in the whole sequence. Moreover, two DNA deletions of approximately 100 and 110 bp were found in the M. leprae katG region, and they seemed to be present in all seven M. leprae isolates tested. These results strongly suggest that M. leprae lacks a functional katG gene and catalase-peroxidase activity.

Dharmendra antigen but not integral M. leprae is an efficient inducer of immunostimulant cytokine production by human monocytes, and M. leprae lipids inhibit the cytokine production

Killed integral Mycobacterium leprae, Mitsuda antigen, and chloroform-treated M. leprae, Dharmendra antigen (Dh-Ag), have been used for the classification of leprosy patients based on cell-mediated immunity. Heat-killed M. leprae also were used as a component of the Convit vaccine. Human blood monocytes were stimulated with M. leprae or Dh-Ag and their cytokine-inducing ability was compared. Monocytes were cultured in the presence of fresh human serum because of the efficiency of cytokine induction and the phagocytosis of M. leprae have been shown to be optimal in the presence of fresh serum. M. leprae and Dh-Ag were equally phagocytosed by monocytes. Dh-Ag was more potent than M. leprae in the induction of immunostimulatory/proinflammatory cytokines, interleukin-1 (IL-1), IL-6 and tumor necrosis factor (TNF). In contrast, a comparable level of IL-1ra, an immunosuppressive cytokine, was induced by M. leprae and Dh-Ag. The lipids extracted from M. leprae induced none of these cytokines by monocytes. Nevertheless, when monocytes were pretreated with the lipids followed by stimulation with Dh-Ag, productions of IL-1, IL-6 and TNF were all inhibited in a dose-dependent manner. However, the lipids did not inhibit the cytokine production induced by other stimuli including BCG and lipopolysaccharide. Moreover the lipids did not affect the production of IL-1ra. These results suggest that the lipids from M. leprae are responsible for the poor cytokine-inducing ability of M. leprae, thus favoring their infection. These results also suggest that Dh-Ag rather than integral M. leprae may be useful as a vaccine candidate because Dh-Ag is able to induce a large amount of cytokines from monocytes.

Purification and properties of a membrane-bound phospholipase B from Mycobacterium lepraemurium

The phospholipid deacylating enzyme was solubilized from the particulate (membrane) fraction of Mycobacterium lepraemurium with Triton X-100 and sodium cholate, and purified 1100-fold to homogeneous state by 5 steps of column chromatography: DE-52, PL-Sepharose (phosphatidylserine-attached sepharose), Mono P, heparin-Agarose and Mono Q column chromatography. The purified enzyme was composed of single polypeptide chain and molecular mass of 37 kDa was estimated for the protein by SDS-PAGE. The isoelectric point was determined about pH 4.6 and the protein was highly resistant to various kinds of proteolytic enzymes. The purified enzyme hydrolyzed both diacyl and monoacyl phospholipids showing that this enzyme was classified to phospholipase B (phospholipase A1/lysophospholipase). This phospholipase B had acidic pH optima and hydrolyzed both neutral phospholipids such as phosphatidylcholine (PC), phosphatidylethanolamine (PE) and acidic phospholipids such as phosphatidylserine (PS), phosphatidylinositol (PI) and phosphatidylglycerol (PG). Various fatty acids such as 12:0, 14:0, 16:0, 18:0 and 18:1 at sn-1 position, and 18:1, 18:2, 18:3 and 16:0 at sn-2 position were liberated from PC, suggesting no strict specificity toward the fatty acyl groups of phospholipids. From the comparison of degradation patterns of phosphatidylcholine with sn-1-[1-14C]- and sn-2-[1-14C]fatty acids, this enzyme was suggested to hydrolyze sn-1 position of phospholipid first and then sn-2 position, as the phospholipase B of M. phlei. This enzyme also attacked 1-acyl- and 2-acyl-lyso-PC at about same rates. The Km values for 1-acyl-2-oleoyl-PC and 2-oleoyl-lyso-PC were estimated 1.6 and 0.75 mM, respectively.

[Rapid detection of acid-fast bacilli with Mycobacteria Growth Indicator Tube (MGIT)]

The BBL MGIT Mycobacteria Growth Indicator Tube is a novel broth based culture system for the detection of mycobacteria from clinical specimens. The tubes consist of a fluorescent indicator embedded in silicone on the bottom of a 16x100 mm round-bottom tube, filled with 4ml of an enriched BBL Middlebrook 7H9 broth base, with 0.25% glycerol. Actively growing mycobacteria consume the oxygen dissolved in the medium and fluorescence will occur when the tubes are observed with a 365nm transilluminator. The purpose of this study is to evaluate comparatively MGIT with 1% Ogawa egg medium by using two hundred and forty-five clinical specimens. The samples were digested, decontaminated and concentrated for culture using N-acetyl-L-cysteine-sodium hydroxide method. Fifty-nine of 245 (24%) clinical samples were culture positive for mycobacteria (43 M. tuberculosis complex, 12 M. avium complex and 4 other species) by one or both test systems. The MGIT detected 4 isolates of M. tuberculosis complex and 6 isolates of M. avium complex not recovered by the Ogawa egg medium, respectively. The mean time of detection of M. tuberculosis complex was 13 days (range: 2-26 days) and 19 days (range: 8-31 days) for MGIT and Ogawa egg medium, respectively, and that of M. avium complex was 5 days (range: 2-8 days) and 16 days (range: 6-22 days) for the MGIT and Ogawa egg medium, respectively. Overall, the MGIT is a sensitive culture system for the detection of mycobacteria from clinical specimens, is easy to use and may be applicable to clinical laboratories.

Carboxyl terminus of inducible nitric oxide synthase. Contribution to NADPH binding and enzymatic activity

Cloning of a nitric oxide synthase (NOS) from RAW 264.7 mouse macrophages (Xie, Q.-w., Cho, H. J., Calaycay, J., Mumford, R. A., Swiderek, K. M., Lee, T. D., Ding, A., Troso, T., and Nathan, C. (1992) Science 256, 225-228) yielded two sets of cDNA: one with a longer coding region of 1144 amino acids, whose sequence matched that of the purified protein, and another with a shorter coding region of 1122 amino acids, in which the last 10 carboxyl-terminal amino acids differed completely from those of the long form. We have now found that the short form lacks NOS activity. To determine the basis of this defect, we prepared recombinant chimeric, deletional, and point mutants of the long and short NOS variants, monitored their expression by immunoblot, and tested their enzymatic activity. By itself, lack of the 22-carboxyl-terminal residues of the long form NOS was scarcely consequential. Mutation of Phe1122, the only aromatic residue within one of the longest conserved regions shared by all NOSs of reported sequence, reduced enzymatic activity by 41%. Deletion of 23 carboxyl-terminal amino acids (including Phe1122) reduced activity by 71%. Further loss of Ile1121, another completely conserved residue, reduced activity by 95%, and with the deletion of the rest of the conserved region, NOS activity was undetectable. Normal dimerization and binding of heme and calmodulin by the short variants militated against distortions of tertiary structure affecting the amino-terminal half or middle portion of the protein. In contrast, the short variants were deficient in binding to NADPH, as predicted by a model of tertiary structure based on that of spinach ferredoxin-NADP+ reductase. This is the first demonstration that the carboxyl terminus of NOS is a functionally critical region.

Cloning and sequence determination of the gene coding for the elongation factor Tu of Mycobacterium leprae

Elongation factor Tu (EF-Tu) plays an important role in protein biosynthesis and is susceptible to antibiotics in prokaryotes like Escherichia coli. In order to understand the primary structure of EF-Tu in the intracellular pathogenic bacterium Mycobacterium leprae, the gene (tuf gene) coding for this protein was cloned and sequenced. The gene contains a coding region of 1,188 bp with GUG as start codon. The deduced amino acid sequence has 396 amino acids with a molecular weight of 43.6 kDa. Putative GTP-binding sites are located at amino acid positions 19-24, 83-87, and 138-141. Comparison of M. leprae EF-Tu amino acid sequence with those of M. tuberculosis, Micrococcus luteus, E. coli, and Salmonella typhimurium reveals 74-95% homology. Mitochondrial EF-Tu of Saccharomyces cerevisiae (62%) and chloroplast EF-Tu of Arabidopsis thalina (65.6%) also show strong homology with that of M. leprae. In contrast, the EF-Tu of the archaebacterium Halobacterium marismoruti exhibits relatively less homology (36.7%). Southern hybridization of M. leprae tuf gene with genomic DNA of slow growing and fast growing mycobacteria and related species like Corynebacterium fascians and Nocardia asteroides suggests that the gene is highly conserved in these organisms.

Role of transcription factor NF-kappa B/Rel in induction of nitric oxide synthase

The promoter of the murine gene encoding inducible nitric oxide synthase (iNOS) contains an NF-kappa B site beginning 55 base pairs upstream of the TATA box, designated NF-kappa Bd. Reporter constructs containing truncated promoter regions, when transfected into macrophages, revealed that NF-kappa Bd is necessary to confer inducibility by bacterial lipopolysaccharide (LPS). Oligonucleotide probes containing NF-kappa Bd plus the downstream 9 or 47 base pairs bound proteins that rapidly appeared in the nuclei of LPS-treated macrophages. The nuclear proteins bound to both probes in an NF-kappa Bd-dependent manner, but binding was resistant to cycloheximide only for the shorter probe. The proteins binding both probes reacted with antibodies against p50 and c-rel but not RelB; those binding the shorter probe also reacted with anti-RelA (p65). Pyrrolidine dithiocarbamate, which acts as a specific inhibitor of NF-kappa B, blocked both the activation of the NF-kappa Bd-binding proteins and the production of NO in LPS-treated macrophages. Thus, activation of NF-kappa B/Rel is critical in the induction of iNOS by LPS. However, additional, newly synthesized proteins contribute to the NF-kappa Bd-dependent transcription factor complex on the iNOS promoter in LPS-treated mouse macrophages.

Susceptibility of severe combined immunodeficient (SCID) mice to Mycobacterium leprae: multiplication of the bacillus and dissemination of the infection at early stage

Inoculation of M. leprae were made into the both hind feet at a dose of 4.8 x 10(6) bacilli per foot in order to determine the susceptibility to M. leprae of SCID mice which is severely deficient in both T- and B cell immunity. SCID mice was found to have an extremely high susceptibility to M. leprae, and the progress of infection observed in the SCID mice were shown a rapid systemic spread of infection at the all over the tissues as well as the growth of the leprosy bacilli at the site of inoculation. Therefore, SCID mice can be used as a suitable multibacillary model for the study of leprosy.

[Phospholipid-deacylating activities of the mouse peritoneal macrophages during phagocytosis]

In the macrophages (M phi) obtained from mouse peritoneal exudates, five kinds of phospholipid-deacylating activities were detected using phosphatidylethanolamine (PE) and phosphatidylcholine (PC) labeled with [1-14C]oleic acid either in 1- or 2- position and 1- [1-14C]oleoyl-lysoPE, as substrates. Two types of phospholipipase A1 with pH optima of 4 to 6 and 8, respectively, and two types of phospholipase A2 activities with pH optima of 4 to 5 and 8, respectively, were identified. A detected lysophospholipase activity exhibited a broad pH optimum between 4 and 8. Both types of the phospholipase A1 and A2 of M phi hydrolyzed PE more than PC. Exogenously added Ca2+ did not increase the enzymatic activities. A comparison was made of three kinds of the M phi-phospholipid deacylating activities at pH8, after challenging the M phi with Mycobacterium lepraemurium, Escherichia coli, zymosan, or latex beads for 17 hours at 37 degrees C. The bacteria used to the phagocytosis were autoclaved. When the M phi were challenged with M. lepraemurium, the phospholipase A1, A2 and lysophospholipase activities were stimulated by about 160%, 150% and 140%, respectively. However, when challenged with E. coli, the phospholipase A1 activity remarkably decreased by about a third, although the phospholipase A2 activity was stimulated by about 150% that is similar to the challenge with M. lepraemurium. An inflammatory substance, zymosan seemed an effective inducer of the phospholipase A2, the enzymatic activity was remarkably stimulated by 260%, when challenged with 200 micrograms of zymosan. The increase in phospholipase A2 activity of the M phi pretreated with the bacteria or zymosan seems to result in an increase in the hydrolysis of arachidonic acid from the M phi-phospholipids to synthesize its inflammatory oxygenated metabolites. The lysophospholipase activity was not stimulated by the substances used to challenge the M phi, except for M. lepraemurium. No significant increase in three kinds of phospholipid-deacylating activities was observed after challenging the M phi with latex beads. It was considered from the above results that the M phi-phospholipid-deacylating activities at pH8 might be affected by sort of the ingested substances.

A new method for measurement of surfactant specific apoprotein in amniotic fluid

A simple and rapid method for the quantitative measurement of surfactant specific apoprotein concentration in amniotic fluid was developed using the measurement of immunological reactions by the nephelometric technique. Use of this method made it possible to measure 0.5-8.0 micrograms apoproteins per ml within approximately 70 min. Surfactant specific apoproteins in 54 samples of amniotic fluid were measured using the method. The surfactant specific apoprotein concentration in amniotic fluid increased from 1.03 +/- 0.51 micrograms/ml (mean +/- S.D.) at 26-30 weeks of gestation to 4.45 +/- 2.08 micrograms/ml at 36 weeks of gestation or more. Among premature infants, who were delivered within 24 h afer amniocentesis, surfactant specific apoprotein concentration was less than 1.5 micrograms/ml in three infants with respiratory distress syndrome (RDS), and more than 2.1 micrograms/ml in six without RDS. The results indicated that the quantitative measurement of surfactant specific apoprotein in amniotic fluid is effective in predicting the fetal lung maturity, and that simplicity and rapidity make our method useful for clinical application.

[Studies on surface tension of amniotic fluid with special emphasis on evaluating fetal lung maturity]

In order to establish a simple and rapid test for the determination of fetal lung maturity, surface tension (ST) of lipid extracts prepared from amniotic fluid samples obtained from 54 women was measured by Wilhelmy's method. The patterns of ST were classified into three types. Type I: ST of 45 dyne/cm or more at 200 microliters of extract and 36 dyne/cm or more at 350 microliters. Type II: ST of 45 dyne/cm or more at 200 microliters and less than 36 dyne/cm at 350 microliters. Type III: ST less than 45 dyne/cm at 200 microliters. L/S ratio was 2 or more (greater than or equal to 2) in 7 of 23 cases (30.4%) with Type I patterns, 2 of 6 cases (33.3%) with Type II patterns, and 24 of 25 cases (96.0%) with Type III patterns. ST of mature amniotic fluid centrifuged for 10 min. at 5,000 X g and 10,000 X g was higher than ST of mature amniotic fluid centrifuged at 450 X g and 1,000 X g, but ST of immature amniotic fluid showed no significant difference in ST at different centrifugal forces. Contamination with meconium and blood was found to lower ST of immature amniotic fluid remarkably. ST of amniotic fluid lipid extract appeared to be a simple, rapid and reliable method for the assessment of fetal lung maturity.

Origin of lysozyme in amniotic fluid

We reported in a previous paper that the pattern of change in the lysozyme content of normal amniotic fluid during pregnancy resembles indices of fetal maturity such as L/S ratio, creatinine concentration and amylase activity. In order to clarify the origin of amniotic fluid lysozyme and to determine whether or not the amniotic fluid lysozyme concentration indicates the maturity of some specific fetal organ, we measured the lysozyme content of samples of materials considered to be possible sources of amniotic fluid lysozyme. These materials were amnion and--taken immediately after birth--saliva, urine and cord serum. Lysozyme content was 36.5 +/- 6.7 micrograms/ml in the saliva samples, 5.3 +/- 0.9 micrograms/ml in the urine samples, and 17.4 +/- 4.4 micrograms/ml in the cord serum samples. It is unclear, however, which material was the most important source of amniotic fluid lysozyme. The results suggested that homogenized amnion samples contained lysozyme, although the content was low, and that amnion tissue produced lysozyme in vivo. Lysozyme is an enzyme found in the lysozymes of cells. The results of this study provide evidence that amniotic fluid lysozyme originates from many sources.

[Origin of low molecular weight protein in amniotic fluid]

This study was designed to clarify the origin of some low molecular weight (M.W.) proteins in amniotic fluid. Fragments of amniotic membrane were incubated in Krebs solution for six hours. During the incubation period, 2 ml samples of solution were collected at 5, 15, 30, 60, 120, 180, 360 minutes. The protein concentration of samples was measured with a LASER"NEPHELOMETER. The protein concentration increased significantly from 1.25 +/- 0.21 mg/g.w.w. at 60 minutes to 2.33 +/- 0.67 mg/g.w.w. of amniotic membrane at 360 minutes (p less than 0.001). Samples were also analyzed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Proteins of M.W. less than 56 X 10(3) formed several bands, including band 15 (M.W. = 38 X 10(3)), bands 18-19 (M.W. = 23-25 X 10(3)) and band 21-23 (M.W. = 13-19 X 10(3)). Neonatal saliva and urine were also analyzed by SDS-PAGE. The saliva contained proteins of bands 15 and 20 (M.W. = 22 X 10(3)), and the urine a protein of band 14-15 (M.W. = 38-45 X 10(3)). Although the protein of band 20 was the greatest percentage of total protein in saliva samples, it could not be detected in amniotic fluid. Therefore, saliva was probably not a source of low M.W. proteins in amniotic fluid. Amniotic fluid proteins of band 15 probably originated from fetal urine. And proteins of band 21-23 were probably synthesized by the amniotic membrane.

Evaluation of amniocentesis guided by real-time ultrasonic tomography

The purpose of this study was to evaluated the success rate and safety of amniocentesis guided by real-time ultrasonic tomography. Two hundred and fifty amniocenteses were done on pregnant Japanese women of various gestational ages at Kyushu University Hospital from October 1978 to July 1981. These amniocenteses were dependent on the following definite indications: risk of chromosomal disorder 160 (64%), diagnosis of congenital malformation 37 (14.8%), estimation of fetal maturation 37 (14.8%), and Rh isoimmunization 16 (6.4%). Results were as follows: 1. Amniotic fluid was successfully collected 246 times (98.4%). There were 4 failures (91.6%), all associated with oligohydramnios in the third trimester. Of the successful tappings, 215 (87.4%) were single taps. The other cases required two or three taps. No significant difference was found between the success rate of single tappings done in the first, second, and third trimester. 2. Blood-stained amniotic fluid was obtained from 13 subjects (5.3%). In five cases, the placenta had been penetrated by the needle. The incidence of bloody taps was significantly higher for cases of transplacental tapping (5/28) than for those of decidual puncture (9/222). 3. In 16 subjects, immediately after removal of the puncture needle, bleeding from the uterine wall or the placenta was observed as falling droplets in the picture on the scope. In the transplacental tappings, such bleeding continued for longer than 60 seconds, and in the other tappings no longer than 120 seconds.

Phospholipid deacylating activities in murine leprosy bacilli

1) The particulate fraction of cultivated murine leprosy bacilli (Mycobacterium lepraemurium, rough colonies of the Hawaiian-Ogawa strain) contained phospholipid deacylating activities with acidic pH optima. It hydrolyzed phosphatidylcholine and phosphatidylethanolamine at similar rates, and phosphatidylinositol oligomannosides more slowly. It also hydrolyzed 1-acyl- and 2-acyl-GPCs (sn-glycerol 3-phosphocholine) more rapidly than phosphatidylcholine. 2) Ca2+ did not stimulate either diacyl- or monoacyl-hydrolase activity. Triton X-100 and Emulgen 913 had little influence on the hydrolysis of phosphatidylcholine, but at rather high concentrations inhibited the hydrolyses of 1-acyl- and 2-acyl-GPCs. Iron ions strongly inhibited the hydrolysis of phosphatidylcholine, but caused little or no inhibition of the deacylations of 1-acyl- and 2-acyl-GPCs. 3) With 1-[stearoyl-14C]phosphatidylcholine and 2-[oleoyl-14C]phosphatidylcholine as substrates, both labeled fatty acid and lysophosphatidylcholine were produced. Labeled fatty acid appeared more rapidly from 2-[oleoyl-14C]phosphatidylcholine than labeled lysophosphatidylcholine, while labeled lysophosphatidylcholine was produced more than labeled fatty acid from 1-[stearoyl-14C]phosphatidylcholine in the early stage of incubation.

Multiple components of endo-polyguluronide lyase of Pseudomonas sp

A lyophilized alginate lyase preparation obtained from dialyzed extract of sonicated Pseudomonas sp. cells was fractionated by gell filtration on a Sephadex G-150 column, and three alginate lyase [EC4.2.2.3] fractions, peaks I, II, and III, were obtained. They were remarkably thermolabile. The lyase fractions degraded two kinds of alginate fragments, a polygluuronide (SG), and a polyuronide consisting of both mannuronic and guluronic acid residues (SMG), as well as commerical alginate, but were virtually inactive toward polymannuronide fragment (SM). The modes of degradation of these substrates by the lyase fractions were endowise with different degrees of randomness. Attack by the peak I fraction was more random than those by peaks II and III. The main lysis products formed from SG and SMG by these layses were identified as mixtures of unsaturated tri- and monouronides. The unsaturated triuronide from SG was deltatugg and SMG yielded a mixture of deltaUGG and a poorly characterized unsaturated trimer, possibly deltaUMG. However, the patterns of monomer and trimer production by theselyase fractions changed in different ways during incubation.

Fine structure of SMG alginate fragment in the light of its degradation by alginate lyases of Pseudomonas sp

An alginate fragment named SMG, consisting of mannuronic (M) and guluronic acid residues (G)(DP=25), was prepared from the partial acid hydrolysate of a commercial alginate. Two subfractions, SMG-ppt (DP=52) and SMG-sup (DP=18) were obtained from SMG by fractionation with MgC12 and CaC12. The M/G ratios of these alginate fragment were 1.4-1.9. Their lysis products by a pseudomonad alginate lyase [EC 4.2.2.3] preparation were fractionated by gel filtration, giving similar patterns. The major products in their digests were unsaturated monouronides (53-50%) and triuronides (30-35%). The former was identified as a delta4,5-hexuronic acid (deltaU) and the latter was identified as a mixture of delta4,5-hexuronosyl-(1 leads to 4)-beta-D-mannuronosyl-(1 leads to 4)-L-guluronic acid (deltaUMG) and delta4,5-hexuronosyl-(1 leads to 4)-alpha-L-guluronosyl-(1 leads to 4))L-guluronic acid (deltaUGG). The two unsaturated triuronides were present in roughly equal amounts. The presence of 4-O-alpha-L-guluronosyl-L-guluronic acid (GG) and 4-O-beta-D-mannuronosyl-L-guluronic acid (MG) or 4-O-beta-L-guluronosyl-D-mannuronic acid (GM) was also demonstrated inthe digest. Moreover, indirect evidence suggested nonreducing terminal deltaU residue and free deltaU in the digest to be derived more from M than G of the original SMG. Thus, it was concluded that more than one-third of uronic acid residues of SMG molecules may be composed of almost equal amounts of MG and GG sequences, most of which may be connected by M to form MMG and MGG sequences, respectively.

Substrate specificity of endo-polyguluronide lyases from Pseudomonas sp. on the basis of their kinetic properties

Two endo-alginate lyases [EC 4.2.2.3] differing in their mode of degradation of substrates and practically free of polymannuronide lyase activity were partially purified from Pseudomonas sp. cells. Their substrate specificities were investigated for two different kinds of alginate fragments; a polyguluronide (SG) and a polyuronide consisting of mannuronic (M) and guluronic (G) acid residues (SMG). The effects of various salts and some organic compounds such as EDTA and p-chloromercuribenzoate on the degradation of the two substrates were similar. High concentrations of the substrates similarly inhibited the action ofthe lyases, giving a bell-shaped plot. A polymannuronide alginate fragment (SM) which was a substrate for polymannuronide lyase but was not attacked by these guluronide lyases also inhibited the degradation of SG and SMG. The overall degradation velocities of a mixture of SG and SMG by both lyases coincided with those calculated from the Michaelis-Menten formula. Based on the above results, it was concluded that SG and SMG are attacked by the same endo-polyguluronide lyase.

Metabolism of triacylglycerol in Mycobacterium smegmatis

Mycobacterium smegmatis cells incorporated [1-14C]oleic acid into triacylglycerols (TG) from the medium more rapidly than shorter chain fatty acids, caprilic and butyric acids. This incorporation was inhibited more strongly by 10(-3) M N-ethylmaleimide than by 10(-3) M KCN. [14C]TG in the bacterial cells was utilized when the cells were in poor nutritional conditions, such as phosphate buffer (pH 7.0) containing oleic acid. Accumulation of TG was observed in the cells at late stages of growth. Diglyceride acyltransferase [EC 2.3.1.20] activity was detected in a cell-free extract from this bacterium. The pH optimum of this enzyme was between pH 7 and 9. F- and Tween 20 showed remarkable enhancing and inhibitory effects, respectively.

Effect of metal ions in the culture medium on the stearoyl-coenzyme A desaturase activity of Mycobacterium phlei

A particulate fraction prepared from Mycobacterium phlei grown in a metal-deficient medium exhibited a greatly reduced activity of stearoyl-CoA desaturase compared to that from normally grown cells. Metal deficiency, however, had no effect on the FAD-dependent NADPH-cytochrome C reductase activity, which has been suggested to participate in the desaturation process. When the cells were grown in the deficient medium supplemented with both Fe2+ and Mg2+, the desaturase activity was restored to the normal level. Supplementation with Mg2+ alone promoted growth but did not restore the desaturase activity, whereas Fe2+ alone did cause a significant restoration. Among the various metal ions tested, only Fe2+ and Fe3+ enhanced the formation of desaturase activity in the deficient medium. When added to the assay medium in vitro, Fe2+ and Fe3+ did not stimulate the desaturase activity of the particulate fraction from the deficient cells. Cultivation in the metal-deficient medium had essentially no effect on the levels of cytochromes in the particulate fraction, but dramatically decreased the non-heme iron content and the amount of a high-spin ferric species exhibiting an ESR signal at g=4.3. No labile sulfur could be detected in the normal or metal-deficient particulate fractions. It is concluded that the presence of iron ions in the culture medium is necessary for the synthesis and/or assembly of the terminal portion of the desaturase system.