Antioxidant enzymes suppress nitric oxide production through the inhibition of NF-kappa B activation: role of H(2)O(2) and nitric oxide in inducible nitric oxide synthase expression in macrophages

Reactive molecules O(-)(2), H(2)O(2), and nitrogen monoxide (NO) are produced from macrophages following exposure to lipopolysaccharide (LPS) and involved in cellular signaling for gene expression. Experiments were carried out to determine whether these molecules regulate inducible nitric oxide synthase (iNOS) gene expression in RAW264.7 macrophages exposed to LPS. NO production was inhibited by the antioxidative enzymes catalase, horseradish peroxidase, and myeloperoxidase but not by superoxide dismutase (SOD). In contrast, the NO-producing activity of LPS-stimulated RAW264.7 cells was enhanced by the NO scavengers hemoglobin (Hb) and myoglobin. The antioxidant enzymes decreased levels of iNOS mRNA and protein in LPS-stimulated RAW264.7 cells, whereas the NOS inhibitor N(G)-monomethyl-L-arginine as well as Hb increased the level of iNOS protein but not mRNA, indicating that NO inhibits iNOS protein expression. NF-kappa B was activated in LPS-stimulated RAW264.7 cells and the activation was significantly inhibited by antioxidant enzymes, but not by Hb. Similar results were obtained using LPS-stimulated rodent peritoneal macrophages. Extracellular O(-)(2) generation by LPS-stimulated macrophages was suppressed by SOD, but not by antioxidative enzymes, while accumulation of intracellular reactive oxygen species was inhibited by antioxidative enzymes, but not by SOD. Exogenous H(2)O(2) induced NF-kappa B activation in macrophages, which was inhibited by catalase and pyrroline dithiocarbamate (PDTC). H(2)O(2) enhanced iNOS expression and NO production in peritoneal macrophages when added with interferon-gamma, and the effect of H(2)O(2) was inhibited by catalase and PDTC. These findings suggest that H(2)O(2) production from LPS-stimulated macrophages participates in the upregulation of iNOS expression via NF-kappa B activation and that NO is a negative feedback inhibitor of iNOS protein expression.

Funisitis and chorionic vasculitis: the histological counterpart of the fetal inflammatory response syndrome

OBJECTIVE

To determine whether there is a relationship between the presence of histological signs of inflammation in the extraplacental membranes and umbilical cord and the concentrations of fetal plasma interleukin-6 (IL-6).

METHODS

The study examined a cohort of patients who were admitted with preterm labor or preterm premature rupture of the membranes (PROM) and who underwent cordocentesis. Inclusion criteria included fetal plasma available for IL-6 determination, histological examination of the umbilical cord and placenta, and delivery within 48 h of the procedure. This last criterion was used to preserve a meaningful temporal relationship between fetal plasma IL-6 and the results of histological examination of the placenta. Fetal plasma IL-6 was determined by a high sensitivity ELISA. Forty-five patients were available for study: 18 patients had preterm labor with intact membranes and 27 had preterm PROM.

RESULTS

The incidence of funisitis was 44.4% (20/45): 27.8% (5/18) in patients with preterm labor and intact membranes and 55.6% (15/27) in patients with preterm PROM. The median values of fetal plasma IL-6 in patients with funisitis, chorioamnionitis without funisitis, and non-inflamed membranes were 51.4, 18.4 and 5.2 pg/ml, respectively. After log transformation of the fetal plasma IL-6 concentration, the means differed significantly from each other (ANOVA, p < 0.02). There was no difference in log fetal plasma IL-6 concentration between patients with funisitis and those with chorioamnionitis without funisitis. The difference in mean concentration of log fetal plasma IL-6 between patients with funisitis or chorionic vasculitis and those without inflammation was highly significant (post-hoc test, p = 0.01 and p < 0.01, respectively). Fetuses with fetal plasma IL-6 > 11 pg/ml had a significantly higher rate of histological signs of inflammation in the extra-placental membranes and umbilical cord than those with fetal plasma IL-6 < 11 pg/ml (funisitis: 55.6% (15/27) vs. 27.8% (5/18), p < 0.05; chorionic vasculitis: 55.6% (15/27) vs. 12.5% (2/16), p < 0.01; chorioamnionitis only: 25.9% (7/27) vs. 16.7% (3/18), p < 0.05; no inflammation: 18.5% (5/27) vs. 55.6% (10/18), p < 0.05, respectively). Fetuses with funisitis had significantly higher rates of clinical and histological chorioamnionitis, and neonatal infectious morbidity (proven + suspected sepsis) than fetuses without funisitis (40% (8/20) vs. 8% (2/25), 90% (18/20) vs. 36% (9/25), and 40% (8/20) vs. 4% (1/25), respectively; p < 0.01 for each). Fetuses with chorionic vasculitis had significantly higher rates of clinical and histological chorioamnionitis as well as neonatal infectious morbidity (proven + suspected sepsis) than fetuses without chorionic vasculitis (100% (17/17) vs. 42.3% (11/26), p < 0.01; 82.4% (14/17) vs. 50.0% (13/26), p = 0.05; and 41.2% (7/17) vs. 7.7% (2/26), p = 0.01).

CONCLUSION

Fetal plasma IL-6 concentration is significantly associated with the presence of inflammatory lesions in the extraplacental membranes and umbilical cord. Fetuses with fetal plasma IL-6 > 11 pg/ml had a significantly higher rate of funisitis and/or chorionic vasculitis than fetuses with fetal plasma IL-6 < 11 pg/ml. These findings suggest that funisitis/chorionic vasculitis is the histological manifestation of the fetal inflammatory response syndrome.

The expression of Bok is regulated by serum in HC11 mammary epithelial cells

Epithelial cells within the mammary gland undergo apoptosis during weaning. To determine the expression of Bok mRNA (a member of the pro-apoptotic Bcl-2 family) in the mammary gland and its regulation, we examined the expression of the Bok transcript in the mouse mammary gland and HC11 mammary epithelial cells in culture through RT-PCR. The Bok mRNA expression was found in the mammary gland. The expression of the Bok mRNA level was induced through serum starvation and overexpression of Bok induced apoptosis in HC11 cells in culture. These results indicate that the expression of Bok mRNA in the mammary gland is regulated through serum starvation. It also may be related to the mammary involution.

The role of nitric oxide in ocular surface diseases

The role of nitric oxide (NO) in ocular surface diseases remains unknown. We investigated the conditions leading to increase NO generation in tears and the main sources of ocular surface tissue. We evaluated the possibility of a dual action (cell survival or cell death) depending on the amount of NO. The concentration of nitrite plus nitrate, the stable end-product of NO, was measured in the tears of various ocular surface diseases. We also examined the main source of nitric oxide synthase (NOS) using immunohistochemical staining & Western blot analysis. When cultured human corneal fibroblasts were treated with NO producing donor with or without serum, the viability of cells was studied. We found that sources of NO in ocular surface tissue primarily included corneal epithelium, fibroblasts, endothelium and inflammatory cells. Three forms of NOS (eNOS, bNOS, & iNOS) were expressed in experimentally induced inflammation. Cell death by NO revealed TUNEL positive staining, however in the EM finding, this NO specific cell death was an atypical necrosis showing perinuclear large vacuolization and mitochondrial swelling. In the fibroblasts culture system, the NO donor (SNAP, S-nitroso-N-acetyl-D, L-penicillamine) prevented the death of corneal fibroblasts caused by serum deprivation in a dose dependent manner up to 500 m SNAP, although a higher dose decreased cell viability. This study suggested that NO might act as a double-edged sword in ocular surface disease depending on the degree of inflammatory condition related with NO concentration.

Colon-specific prodrugs of 5-aminosalicylic acid: synthesis and in vitro/in vivo properties of acidic amino acid derivatives of 5-aminosalicylic acid

5-aminosalicyl-L-aspartic acid (5-ASA-Asp) and 5-aminosalicyl-L-glutamic acid (5-ASA-Glu) were synthesized and their properties as colon-specific prodrugs of 5-aminosalicylic acid (5-ASA) were investigated employing rats as test animals. Incubation of 5-ASA-Asp and 5-ASA-Glu with the homogenates of tissue and contents of stomach or small intestine released no 5-ASA, indicating that they were stable in this condition. Incubation of 5-ASA-Asp with the cecal contents released 5-ASA 37%, whereas 5-ASA-Glu released only 8% of the dose in 16 h. Plasma concentration of 5-ASA-Asp after intravenous administration decreased rapidly and became undetectable in 60 min. No 5-ASA was detected in the blood, which indicated 5-ASA-Asp was stable in the plasma. After oral administration of 5-ASA-Asp, concentration of 5-ASA, its metabolite N-acetyl-5-ASA, and 5-ASA-Asp in the plasma, feces, and urine was determined. In the plasma, 5-ASA-Asp was not detected and the concentration of 5-ASA or N-acetyl-5-ASA was very low. About 33% of the administered dose was recovered as 5-ASA and N-acetyl-5-ASA and 43% as 5-ASA-Asp from feces, and 20% as 5-ASA and N-acetyl-5-ASA and 1% as 5-ASA-Asp from urine in 24 h. These results suggested that most of 5-ASA-Asp was delivered to the large intestine and about half of the administered dose was activated to liberate 5-ASA. After oral administration of free 5-ASA, fecal recovery was only 7% of the dose in 24 h and more than 80% was recovered from urine. Comparing 5-ASA-Asp and free 5-ASA, the amount of 5-ASA available in the large intestine was much larger, while the amount of 5-ASA in urine, which might be related to the systemic toxicity of 5-ASA, was much lower by the administration of 5-ASA-Asp than free 5-ASA.

Synthesis and evaluation of N-acyl-2-(5-fluorouracil-1-yl)-D,L-glycine as a colon-specific prodrug of 5-fluorouracil

N-nicotinyl-2-(5-fluorouracil-1-yl)-D,L-glycine (NFG) and N-isonicotinyl-2-(5-fluorouracil-1-yl)-D,L-glycine (INFG) were synthesized as colon-specific prodrugs of 5-fluorouracil (5-FU). As N-aromatic acyl amides of glycine, they are expected to be stable in the upper intestine and delivered to the colon as an intact form if they are nonabsorbable. Microbial hydrolysis of amide bond in the colon will give 2-(5-fluorouracil)-D,L-glycine, which releases 5-FU by spontaneous decomposition. NFG and INFG were soluble in water and stable in pH 1.2 and 7.4 buffer solutions. The apparent partition coefficient of NFG or INFG in 1-octanol/pH 7.4 phosphate buffer solution at 37 degrees was 0.025 or 0.024, respectively. On incubation with cecal contents of rats, conversion of NFG or INFG proceeded only 9 or 5% in 8 h, respectively, producing 5-FU and a metabolite. The metabolite formation was inhibited in the presence of diazouracil, a dihydrouracil dehydrogenase inhibitor. The HPLC retention time of the metabolite from the incubation of 5-FU, NFG, or INFG with cecal contents was identical to dihydro-5-fluorouracil (dihydro-5FU). When N-nicotinyl-2-hydroxy-D,L-glycine methyl ester (NHGM) was incubated with the cecal contents, the extent of amide bond hydrolysis was 85% in 24 h. The result suggested that steric hindrance imposed by 5-FU at 2-position of glycine retarded the hydrolysis of the amide bond in NFG or INFG and suppressed the prodrug conversion.

Tracheal compression by elongated aortic arch in patients with congenitally corrected transposition of the great arteries

We investigate the tracheal compression by aortic arch in patients with congenitally corrected transposition of the great arteries. Fourteen patients whose ascending aorta was connected to descending aorta on the contralateral side were divided into two groups according to the severity of tracheal compression on lateral angiogram: group 1 (stenosis > or = 50%, eight patients) and group 2 (stenosis < 50%, six patients). We compared the following variables between the groups: aortic size, lateral displacement of ascending aorta, retrosternal space, and contour of aortic arch. Spiral computed tomography (CT) was done in five patients of group 1. The ratio between measured and normal diameters of ascending aorta of group 1 was significantly larger than that of group 2 (1.57 +/- 0.14 compared to 1.19 +/- 0.26, p = 0.014). There was linear correlation between the tracheal compression and aortic size (r = 0.69, p = 0.001). The ascending aorta was positioned more laterally and the aortic arch was located more posteriorly in group 1. In four patients with decreased tracheal compression after surgery, aortic size decreased and the ascending aorta restored its anterior position. Spiral CT showed transversely oriented aortic arch and severe tracheal compression in the anteroposterior direction by aortic arch. The tracheal compression by aortic arch in corrected transposition is common when the descending aorta is located on the contralateral side of the ascending aorta. Aortic size, posterior position, elongation, and end-on appearance of the aortic arch are the useful predictors of tracheal compression.

Exogenous nitric oxide inhibits experimental autoimmune uveoretinitis development in Lewis rats by modulation of the Th1-dependent immune response

Experimental autoimmune uveoretinitis (EAU) is a T cell-mediated autoimmune disease of posterior uvea that closely resembles a human disease. The uveitogenic effector T cell has a Th1-like phenotype [high interferon-gamma (IFN-gamma), low interleukin-4 (IL-4)], and genetic susceptibility to EAU that is associated with an elevated Th1 response. Suppression of CD4+ Th1 cells for the treatment of autoimmune disease is an attractive potential therapeutic approach. Nitric oxide (NO) has been implicated in the pathogenesis of several inflammatory and autoimmune diseases. In this study, we investigated the potential role of NO as an immunoregulator to alter Th1/Th2 cytokine production, as well as to inhibit the interphotoreceptor retinoid binding protein (IRBP)-induced EAU, a CD4+ Th1 cell-mediated autoimmune disease. Injection of IRBP (100 microg) into two footpads resulted in severe EAU. The beginning peak of the disease was days 12 to 15 after immunization. Oral treatment with molsidomine (MSDM), a NO donor, began 24 h before IRBP immunization to the end of the experiments, which resulted in a significant inhibition of the disease by clinical and histopathological criteria. When MSDM was administered until day 21, a complete reduction of incidence and severity of EAU was observed. To investigate the cytokine alterations from Th1 to Th2 cytokines by MSDM, the cytokines were assayed in a culture medium of IRBP-stimulated inguinal lymphocytes. IRBP-immunized rats secreted a high concentration of IFN-gamma and a low concentration of IL-10. In contrast, MSDM treatment enhanced IL-10 secretion and tended to decrease IFN-gamma secretion. In conclusion, we show that the administration of NO suppresses EAU by altering the Th1/Th2 balance of inflammatory immune responses. We suggest that NO may be useful in the therapeutic control of autoimmune uveitis.

Chemical structure and biological activity of a lipid A component from Helicobacter pylori strain 206

The chemical structure of a lipid A, which was obtained as a minor component from lipopolysaccharide of Helicobacter pylori strain 206-1, was determined to be a glucosamine beta-(1 -6) disaccharide 1-(2-aminoethyl)phosphate acylated by (R)-3-hydroxyoctadecanoic acid, (R)-3- hydroxyhexadecanoic acid, and (R)-3-(octadecanoyloxy)octadecanoic acid at the 2-, 3- and 2'-positions, respectively. Compared with the other major lipid A from the same strain, which was previously reported [Suda Y, Ogawa T, Kashihara W et al. Chemical structure of lipid A from Helicobacter pylori strain 206-1 lipopolysaccharide. J Biochem 1997; 121: 1129--1133], the structure was very similar with one exception. An (R)-3-hydroxyhexadecanoic acid was present at the 3-position of the novel lipid A component. The structure is apparently identical to one of the proposals by Moran et al. [Moran AP, Lindner B, Walsh EJ. Structural characterization of the lipid A component of Helicobacter pylori rough- and smooth-form lipopolysaccharides. J Bacteriol 1997; 179: 6453--6463], who concluded the same structure as the so-called major lipid A from the H. pylori strain NCTC 11637 but without isolating a homogeneous component. The endotoxic properties and pro-inflammatory cytokine-inducing activities of this novel tetra-acyl type lipid A were lower than those of previously reported major tri-acyl type lipid A.

Client communication behaviors with health care providers in Indonesia

Patient participation in health care consultations can improve the quality of decision making and increase patients' commitment to the treatment plan. This study examines client participation, operationally defined as client active communication, during family planning consultations in Indonesia. Data were collected on 1203 consultations in the provinces of East Java and Lampung. Sessions were audiotaped and the conversation coded using an adaptation of the roter interaction analysis system (RIAS). Culturally acceptable ways for Indonesian clients to participate in consultations include asking questions, requesting clarification, stating opinions, and expressing concerns. Factors significantly associated with client active communication were, in order of importance, providers' information giving, providers' facilitative communication, providers' expressions of negative emotion, client educational level, and province. The latter suggests the influence of culture on client participation. The results suggest that a combination of provider training and client education on key communication skills could increase client participation in health care consultations.

Helix proximity in OxlT, the oalate:formate antiporter of oxalobacter formigenes. Cross-linking between TM2 and TM11

Experiments were designed to evaluate the proximity of transmembrane helices two (TM2) and eleven (TM11) in the tertiary structure of OxlT, the oxalate:formate exchange transporter of Oxalobacter formigenes. A tandem duplication of the Factor Xa protease cleavage site (IEGRIEGR) was inserted into the central cytoplasmic loop of an OxlT cysteine-less derivative in which an endogenous cleavage site had been eliminated by mutagenesis (R248Q). Using this host, double cysteine derivatives were constructed so as to pair one of seventeen positions in TM2 with one of four positions in TM11. Following treatment of membrane vesicles with Cu(II)(1,10-phenanthroline)(3), molecular iodine, or N,N'-o-phenylenedimaleimide, samples were exposed to Factor Xa, and disulfide bond formation was assessed after SDS-polyacrylamide gel electrophoresis by staining with antibody directed against the OxlT C terminus. In the absence of disulfide bond formation, exposure to Factor Xa revealed the expected C-terminal 22-kDa fragment, a result unaffected by the presence of reductant. By contrast, after disulfide formation, OxlT mobility remained at 35 kDa, and appearance of the 22-kDa fragment required addition of 200 mm dithiothreitol prior to electrophoresis. The four TM11 positions chosen for cysteine substitution lie on a helical face known to interact with substrate. Similarly, TM2 positions supporting disulfide trapping were also confined to a single helical face. We conclude that TM2 and TM11 are in close juxtaposition to one another in the tertiary structure of OxlT.

Subcapital fractures associated with extensive osteonecrosis of the femoral head

The authors reviewed 10 patients with subcapital fractures associated with extensive osteonecrosis of the femoral head and distinguished these fractures from traumatic femoral neck fractures The mean age of the patients was 52 years (range, 36-68 years). Nine patients were younger than 60 years. Eight patients had risk factors for osteonecrosis. Necrosis was extensive and involved nearly the whole femoral head. Fracture occurred at the junction between a necrotic bone and reparative bone and extended downward through the reparative interface to the healthy inferior cortex of the femoral neck. Patients experienced hip pain that was aggravated gradually during a period of 1 to 24 weeks before diagnosis of the fracture. In all patients, the opposite femoral head was involved with osteonecrosis. In two femoral heads, slight collapse or subchondral fracture (crescent sign) also was observed. No patient had a history of precipitating trauma. In patients younger than 60 years with a subcapital fracture, fracture associated with extensive osteonecrosis of the femoral head should be suspected when a history of trauma is not obvious, when the opposite hip shows findings of osteonecrosis, and when the patient has a risk factor of osteonecrosis. In these fractures, osteosynthesis rarely should be considered because of the high failure rate caused by additional progression of extensive osteonecrosis and the probability of nonunion.

Arrestin specificity for G protein-coupled receptors in human airway smooth muscle

Despite a widely accepted role of arrestins as "uncouplers" of G protein-coupled receptor (GPCR) signaling, few studies have demonstrated the ability of arrestins to affect second messenger generation by endogenously expressed receptors in intact cells. In this study we demonstrate arrestin specificity for endogenous GPCRs in primary cultures of human airway smooth muscle (HASM). Expression of arrestin-green fluorescent protein (ARR2-GFP or ARR3-GFP) chimeras in HASM significantly attenuated isoproterenol (beta(2)-adrenergic receptor (beta(2)AR)-mediated)- and 5'-(N-ethylcarboxamido)adenosine (A2b adenosine receptor-mediated)-stimulated cAMP production, with fluorescent microscopy demonstrating agonist-promoted redistribution of cellular ARR2-GFP into a punctate formation. Conversely, prostaglandin E(2) (PGE(2))-mediated cAMP production was unaffected by arrestin-GFP, and PGE(2) had little effect on arrestin-GFP distribution. The pharmacological profile of various selective EP receptor ligands suggested a predominantly EP2 receptor population in HASM. Further analysis in COS-1 cells revealed that ARR2-GFP expression increased agonist-promoted internalization of wild type beta(2)AR and EP4 receptors, whereas EP2 receptors remained resistant to internalization. However, expression of an arrestin whose binding to GPCRs is largely independent of receptor phosphorylation (ARR2(R169E)-GFP) enabled substantial agonist-promoted EP2 receptor internalization, increased beta(2)AR internalization to a greater extent than did ARR2-GFP, yet promoted EP4 receptor internalization to the same degree as did ARR2-GFP. Signaling via endogenous EP4 receptors in CHO-K1 cells was attenuated by ARR2-GFP expression, whereas ARR2(R169E)-GFP expression in HASM inhibited EP2 receptor-mediated cAMP production. These findings demonstrate differential effects of arrestins in altering endogenous GPCR signaling in a physiologically relevant cell type and reveal a variable dependence on receptor phosphorylation in dictating arrestin-receptor interaction.

Copper-catalyzed coupling reaction of terminal alkynes with aryl- and alkenyliodonium salts

[reaction: see text]. The copper iodide-catalyzed cross-coupling of terminal alkynes with hypervalent iodonium salts was accomplished with CuI (10 mol %) and NaHCO3 (2 equiv) in DME/H2O (4:1) at room temperature for 30 min to afford arylalkynes or enynes under mild conditions.

Nitric oxide induces murine thymocyte apoptosis by oxidative injury and a p53-dependent mechanism

Previously, we showed that NO induces thymocyte apoptosis via a caspase-1-dependent mechanism [(1) ]. In the present study, we investigated the role of heme oxygenase, catalase, bax, and p53 in this process. The NO donor, S-nitroso-N-acetyl penicillamine (SNAP), induced DNA fragmentation in thymocytes in a time- and concentration-dependent way. SNAP (100 microM) induced 50--60% apoptosis; higher doses did not increase the rate of apoptosis significantly. SNAP decreased catalase and heme iron (Fe) levels without affecting superoxide dismutase, glutathione, or total Fe stores in thymocytes. SNAP significantly increased the expression of heme oxygenase 1 (HSP-32), p53, and bax but not bcl-2. Treatment with the heme oxygenase inhibitor, tin protoporphyrin IX inhibited SNAP-induced thymocyte apoptosis. Furthermore, thymocytes from p53 null mice were resistant to NO-induced apoptosis. Our data suggest that NO may induce its cytotoxic effects on thymocytes by modulating heme oxygenase and catalase activity as well as up-regulating pro-apoptotic proteins p53 and bax.

Molecular characterization of Hmg2 gene encoding a 3-hydroxy-methylglutaryl-CoA reductase in rice

Three genes encoding 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR, EC1.1.1.34), which converts HMG-CoA into mevalonate in the early key step of the plant isoprenoid pathway, were isolated by RT-PCR and rice cDNA and genomic library screening. A genomic Southern blot analysis confirmed that HMGR genes are present in three copies in rice. Of the three, the HMGR 2 gene (Hmg2) obtained as a cDNA clone and its genomic clone had 4 exons and 3 introns, and encoded a 576 amino acid peptide containing an open reading frame of 1,728 bp with a calculated Mw. of 61,150. The structure of rice Hmg2 had common features, based on its nucleotide and deduced amino acid sequence homologies, with other plant HMGR genes published to date. Rice Hmg2 transcripts were constitutively detected in all parts of the rice plant, except in lamina and their levels were high particularly in the leaf part of the dark-grown seedlings and mature flowers. Our result showed that mRNA levels of rice Hmg2 were strongly induced in seedlings and influorescence in the early development stage. Rice Hmg2 possibly has a housekeeping role involved in the sterol biosynthesis, among the possible roles of plant HMGR genes that have been suggested in other plants [Weissenborn et al. (1995)].

Effect of alpha1-acid glycoprotein expressed in cancer cells on malignant characteristics

The alpha1-acid glycoprotein (AAG) is a prototypical serum acute phase reactant in most mammalian species; it is synthesized mainly in liver parenchymal cells. Recently, we found that mRNAs of AAG were expressed in non-hepatic cancer cells, and the expression levels were regulated by the cytokines--IL-1, IL-6, and TNF-alpha. The functional role of AAG in non-hepatic cancer cells has not yet been established. In order to understand the functional role of the AAG expressed in HT-29 cells, the cancer cells were transfected with cloned cDNA for AAG, or exposed to antisense oligodeoxynucleotide (ODN) for AAG. The colony-forming capacity, invasion, and adhesion to laminin of these transformed cancer cells were measured. Overexpression of AAG by transfection, and inhibition of the AAG expression by antisense ODNs were identified by Western blot as well as nested reverse transcriptase-polymerase chain reaction (nested RT-PCR), respectively. Results showed that the overexpression of AAG by transfection reduced colony-forming capacities, invasion, and adhesion to laminin of the cancer cells; on the other hand, the antisense ODN for AAG elevated colony-forming capacities, invasion, and adhesion to laminin of the cancer cells. These results suggest that AAG, expressed in cancer cells inhibited proliferation, invasion, and metastasis of the cancer cells.

Dopamine receptor regulating factor, DRRF: a zinc finger transcription factor

Dopamine receptor genes are under complex transcription control, determining their unique regional distribution in the brain. We describe here a zinc finger type transcription factor, designated dopamine receptor regulating factor (DRRF), which binds to GC and GT boxes in the D1A and D2 dopamine receptor promoters and effectively displaces Sp1 and Sp3 from these sequences. Consequently, DRRF can modulate the activity of these dopamine receptor promoters. Highest DRRF mRNA levels are found in brain with a specific regional distribution including olfactory bulb and tubercle, nucleus accumbens, striatum, hippocampus, amygdala, and frontal cortex. Many of these brain regions also express abundant levels of various dopamine receptors. In vivo, DRRF itself can be regulated by manipulations of dopaminergic transmission. Mice treated with drugs that increase extracellular striatal dopamine levels (cocaine), block dopamine receptors (haloperidol), or destroy dopamine terminals (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine) show significant alterations in DRRF mRNA. The latter observations provide a basis for dopamine receptor regulation after these manipulations. We conclude that DRRF is important for modulating dopaminergic transmission in the brain.

Serum after partial hepatectomy stimulates iNOS gene transcription via downstream NF-kappa B site

It has been known that the expression of inducible nitric oxide synthase (iNOS) is up-regulated during hepatic regeneration. The present study characterized the molecular mechanisms involved in the transcriptional activation of iNOS gene by using the serum after partial hepatectomy (post-PH serum) in vitro. The post-PH serum rapidly induced iNOS mRNA expression, which was blocked by anti-tumor necrosis factor-alpha (TNF-alpha) antibody in BNL CL.2 cells, murine embryonic liver cell line. In addition, EMSAs using a NF-kappa B-specific oligomer showed that the up-regulated iNOS mRNA expression in cells treated with post-PH serum correlated with transient activation of NF-kappa B complex (p50/p65 heterodimer). Transient transfection of BNL CL.2 cells with iNOS promoter linked to a CAT reporter gene showed the transcriptional activation of iNOS promoter by post-PH serum. Furthermore, site-directed mutational analysis of the two NF-kappa B sites individually or in combination revealed that iNOS expression by post-PH serum is regulated by the downstream NF-kappa B site, but not by upstream NF-kappa B site. Taken together, these results suggest that the downstream NF-kappa B site acts as an essential component for the iNOS expression by post-PH serum during hepatic regeneration.

Molecular Identification of IgE-Dependent Histamine-Releasing Factor as a B Cell Growth Factor

The culture supernatants of LK1 cells, murine erythroleukemia cells, showed B cell-stimulating activity. Purification and NH(2)-terminal sequence analysis revealed that one of the candidates was murine IgE-dependent histamine-releasing factor (IgE-HRF), which is known to induce histamine from basophils. Recombinant IgE-HRF (rHRF) obtained from Escherichia coli- or 293-transformed embryonal kidney cells was tested for B cell-stimulating activity. Both rHRFs stimulated B cell proliferation in a dose-dependent manner. However, boiling or anti-HRF Ab abolished the B cell stimulatory effects of rHRF. Recombinant HRF showed strong synergistic effects with IL-2, IL-4, and IL-5 for B cell activation, with maximal activity in the presence of anti-CD40 AB: Recombinant HRF increased MHC class II expression of B cells. It also increased Ig production from B cells. Treatment with polymyxin B, a neutralizing peptide antibiotic of LPS, did not reduce the activity of rHRF. In addition, FACS analysis using PE-conjugated rHRF showed that HRF bound to B cells. Recombinant HRF up-regulated the expression of IL-1 and IL-6 in B cells. In vivo administration of rHRF or the cDNA for rHRF increased total and Ag-specific Ig synthesis. Taken together, these results indicate that HRF stimulates B cell activation and function.

Five-color-based high-information-content fingerprinting of bacterial artificial chromosome clones using type IIS restriction endonucleases

We have developed a high-information-content fingerprinting (HICF) system for bacterial artificial chromosome (BAC) clones using a Type IIS restriction endonuclease, HgaI, paired with a Type II restriction endonuclease, RsaI. In the method described, unknown five-base overhangs generated with HgaI are partially or fully sequenced by modified fluorescent dideoxy terminators. Using an in-lane size standard labeled with a fifth dye, fragments are characterized by both the size and the sequence of its terminal one to five bases. The enhanced information content associated with this approach significantly increases the accuracy and efficiency of detecting shared fragments among BAC clones. We have compared data obtained from this method to predicted HICF patterns of 10 fully sequenced BACs. We have further applied HICF to 555 BAC clones to assemble contigs spanning 16p11.2 to 16p13.1 of human chromosome 16.

Application of time-of-flight secondary ion mass spectrometry to automobile paint analysis

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) provides a method of elemental analysis that can distinguish among automotive paint samples of the same or nearly the same color. TOF-SIMS survey spectra were employed to determine the relative abundances of elements in the surface layers of the paint chips. The depth profile of paint samples permitted the analysis of small paint chips, the reproducible results for specific elements, and the identification of each car paint. Seventy-three samples of blue, red, white, and silver automobile paints from the major manufacturers in Korea were investigated using high resolution TOF-SIMS technique. It was found that paints of the same color produced by different manufacturers could be distinguished by this technique. TOF-SIMS is a reliable, nondestructive, and small area analyzing method for characterization of the elemental composition of automotive paint chips.

Frequencies of fetal chromosomal abnormalities at prenatal diagnosis: 10 years experiences in a single institution

We present frequencies of fetal chromosomal abnormalities in 4,907 prenatal cytogenetic examinations at Samsung Cheil Hospital from 1988 to 1997 for 10 yr duration. Prenatal karyotypes were undertaken in 3,913 amniotic fluid samples, 800 chorionic villi samples, and 194 percutaneous umbilical blood samples. The frequency of fetal abnormal karyotypes was 3.1% (150 cases). Numerical chromosome abnormalities were 87 cases (1.8%) and structural aberrations of chromosomes were 63 cases (1.3%). In the numerical chromosomal abnormalities, the frequency of trisomy 21 was by far the highest (36 cases), followed by trisomy 18 in 22 cases and sex chromosome aneuploidies in 19 cases. In the structural chromosomal aberrations, 5 cases had the inversions in chromosome 2, 7, 17, and Y. Chromosomal deletions in 6 cases and additions in 4 cases were analysed. Of the remaining 47 translocation in abnormal fetuses, reciprocal translocation was in 26 cases and Robertsonian translocation in 21 cases. Among them, 41 cases were balanced translocation and 6 were unbalanced. Thirty five cases of translocation were inherited from one of the parents. Four had de novo chromosome rearrangements, and 8 cases were unknown.

Preparation of 1,4-oxaselenin from agNO(3)/LDA-assisted reaction of 3-selena-4-pentyn-1-one as potential antitumor agents

1,4-Oxaselenins were synthesized from 3-selena-4-pentyn-1-ones by the use of AgNO(3) and LDA. One of the obtained oxaselenins, 2-(4-chlorophenyl)-6-phenyl-1,4-oxaselenin 5c, showed an inhibitory effect against the proliferation of human cancer cells and inducing effects on the early stage of apoptosis.

Biological behavior and tumorigenesis of subependymal giant cell astrocytomas

In spite of the benign nature of subependymal giant cell astrocytomas (SEGAs), some show massive hemorrhage, rapid growth, and tumor recurrence. This led us to investigate the biological behavior, cell dynamics, and tumorigenesis of SEGAs. All patients (4 men and 3 women; age range, 6-27 years; mean, 13.6 years) had features of tuberous sclerosis complex and obstructive hydrocephalus. One patient had intratumoral bleeding. In two patients, sequential neuroimaging showed a subependymal nodule growing to become a SEGA. All underwent surgical resection without radiation therapy. One tumor recurred and was treated surgically. There were no postoperative deaths. The presence of cytologic atypia, mitoses and vascular proliferation had no implication in terms of the clinical course. MIB-1 labeling indices were low (mean, 0.9), indicating low proliferative potential. Unexpectedly, bcl-2 staining was sparse and bax staining predominated in majority of cases. However, the mean value of terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling index was low. Immunohistochemically, tumors were positive for both glial and neuronal markers. In the majority of our cases, the expression of p53 was low. Only one tumor was focally positive for tuberin. SEGAs have low proliferative potential and apoptotic activity, and exhibit features of mixed glial-neuronal differentiation. In contrast to p53, tuberin is suggested to be the tumor suppressor in this tumor.

Induction of alpha1-acid glycoprotein mRNA by cytokines and differentiation in human colon carcinoma cell

The mRNA for the alpha1-acid glycoprotein (AAG) was expressed not only in hepatoma cells, but also in non-hepatic cancer cells. The expression of the AAG mRNA in HT-29 human colon carcinoma cells is induced by cytokines, IL-6, IL-1, and TNF-alpha, in a manner characteristic of the acute phase response, and the expression of AAG mRNA was up-regulated in differentiated HT-29 cells.

Pathological fracture of the femoral neck as the first manifestation of osteonecrosis of the femoral head

We describe two cases of pathological fracture of the femoral neck occurring as the first manifestation of osteonecrosis of the femoral head (ONFH). No abnormal findings suggestive of ONFH were identified on the radiographs for either of the patients, and the fractures occurred like spontaneous fractures without any trauma or unusually increased activity. The patients' medical history, age, and good bone quality suggested ONFH as a possible underlying cause of the fractures. If we had not suspected ONFH as a predisposing condition, these minimally displaced fractures might have been fixed internally with multiple pins, and this would have led to nonunion or collapse of the femoral head. To avoid inappropriate treatment, ONFH should be considered as a predisposing factor in pathological fractures of the femoral neck.

Nitric oxide as a bioregulator of apoptosis

Nitric oxide (NO), synthesized from l-arginine by NO synthases, is a small, diffusible, highly reactive molecule with dichotomous regulatory roles under physiological and pathological conditions. NO can promote apoptosis (proapoptosis) in some cells, whereas it inhibits apoptosis (antiapoptosis) in other cells. This complexity is a consequence of the rate of NO production and the interaction with biological molecules such as iron, thiols, proteins, and reactive oxygen species. Long-lasting production of NO acts as a proapoptotic modulator by activating caspase family proteases through the release of mitochondrial cytochrome c into the cytosol, upregulation of p53 expression, activation of JNK/SAPK, and altering the expression of apoptosis-associated proteins including Bcl-2 family proteins. However, low or physiological concentrations of NO prevent cells from apoptosis induced by trophic factor withdrawal, Fas, TNFalpha, and lipopolysaccharide. The antiapoptotic mechanism can be understood via expression of protective genes such as heat shock proteins, Bcl-2 as well as direct inhibition of the apoptotic caspase family proteases by S-nitrosylation of the cysteine thiol. Our current understanding of the mechanisms by which NO exerts both pro- and antiapoptotic actions is discussed in this review article.

Sphingosine 1-phosphate protects human umbilical vein endothelial cells from serum-deprived apoptosis by nitric oxide production

Sphingosine 1-phosphate (S1P) can prevent endothelial cell apoptosis. We investigated the molecular mechanisms and signaling pathways by which S1P protects endothelial cells from serum deprivation-induced apoptosis. We show here that human umbilical vein endothelial cells (HUVECs) undergo apoptosis associated with increased DEVDase activity, caspase-3 activation, cytochrome c release, and DNA fragmentation after 24 h of serum deprivation. These apoptotic markers were suppressed by the addition of S1P, the NO donor S-nitroso-N-acetylpenicillamine (100 micrometer), or caspase-3 inhibitor z-VAD-fmk. The protective effects of S1P were reversed by the nitric-oxide synthase (NOS) inhibitor N-monomethyl-l-arginine, but not by the soluble guanylyl cyclase inhibitor 1H-(1,2,4)oxadiazolo[4,3-a]-quanoxaline-1-one, suggesting that NO, but not cGMP, is responsible for S1P protection from apoptosis. Furthermore, S1P increased NO production by enhancing Ca(2+)-sensitive NOS activity without changes in the eNOS protein level. S1P-mediated cell survival and NO production were suppressed significantly by pretreatment with antisense oligonucleotide of EDG-1 and partially by EDG-3 antisense. S1P-mediated NO production was suppressed by the addition of pertussis toxin, an inhibitor of G(i) proteins, the specific inhibitor of phospholipase C (PLC), and the Ca(2+) chelator BAPTA-AM. These findings indicate that S1P protects HUVECs from apoptosis through the activation of eNOS activity mainly through an EDG-1 and -3/G(i)/PLC/Ca(2+) signaling pathway.

Differential regulation of NO availability from macrophages and endothelial cells by the garlic component S-allyl cysteine

Garlic has been used as a traditional medicine for prevention and treatment of cardiovascular diseases. However, the molecular mechanism of garlic's pharmacological action has not been clearly elucidated. We examined here the effect of garlic extract and its major component, S-allyl cysteine (SAC), on nitric oxide (NO) production by macrophages and endothelial cells. The present study demonstrates that these reagents inhibited NO production through the suppression of iNOS mRNA and protein expression in the murine macrophage cell line RAW264.7, which had been stimulated with LPS and IFNgamma. The garlic extract also inhibited NO production in peritoneal macrophages, rat hepatocytes, and rat aortic smooth muscle cells stimulated with LPS plus cytokines, but it did not inhibit NO production in iNOS-transfected AKN-1 cells or iNOS enzyme activity. These reagents suppressed NF-kappaB activation and murine iNOS promoter activity in LPS and IFNgamma-stimulated RAW264.7 cells. In contrast, these reagents significantly increased cGMP production by eNOS in HUVEC without changes in activity, protein levels, and cellular distribution of eNOS. Finally, garlic extract and SAC both suppressed the production of hydroxyl radical, confirming their antioxidant activity. These data demonstrate that garlic extract and SAC, due to their antioxidant activity, differentially regulate NO production by inhibiting iNOS expression in macrophages while increasing NO in endothelial cells. Thus, this selective regulation may contribute to the anti-inflammatory effect and prevention of atherosclerosis by these reagents.

Synthesis and properties of dextran-nalidixic acid ester as a colon-specific prodrug of nalidixic acid

Dextran-nalidixic acid ester (dextran-NA) with a varied degree of substitution (DS) was synthesized as a colon-specific prodrug of nalidixic acid (NA). Solubility in water (mg/ml) of dextran-NA with DS (mg NA/100 mg dextran-NA) of 7, 19, or 32 was 57.57 (equivalent to 4.00 mg NA/ml), 0.53 (equivalent to 0.10 mg NA/ml), or 0.03 (equivalent to 0.01 mg NA/ml), respectively, and that for NA was 0.03 at 25 degrees C. To ensure the chemical stability of dextran-NA at conditions similar to those of the stomach and small intestine, dextran-NA was placed in a solution of pH 1.2 hydrochloric acid buffer or pH 6.8 phosphate buffer and incubated at 37 degrees C; no NA was detected during the 6 h of the incubation period, which indicated that dextran-NA might be chemically stable during the transit through the gastrointestinal tract. Degree of depolymerization (%) by dextranase determined by the 2,4-dinitrosalicylic acid (DNS) method at 37 degrees C for dextran-NA with DS of 7, 19, or 32 was 81, 68, or 8, respectively, in 8 h, and that for dextran was 91. When dextran-NA (equivalent to 50 microg of NA) with a DS of 7 or 17 was incubated with cecal contents (100 mg) of rats at 37 degrees C, the extent of NA released in 24 h was 41% or 32% of the dose, respectively. NA was not liberated from the incubation of dextran-NA with the homogenate of tissue and contents of the small intestine.

Concentrations and sources of VOCs in urban domestic and public microenvironments

Concentrations of 15 VOCs including 1,3-butadiene, benzene, and styrene were measured in a wide range of urban microenvironments, viz: homes, offices, restaurants, pubs, department stores, coach and train stations, cinemas, libraries, laboratories, perfume shops, heavily trafficked roadside locations, buses, trains, and automobiles. For most target VOCs-including 1,3-butadiene and benzene-mean concentrations at heavily trafficked roadside locations were exceeded by those in automobiles and were comparable to those in pubs and train stations. With regard to indoor-outdoor relationships in homes, this study revealed higher mean indoor concentrations, no correlation between simultaneously measured indoor and outdoor concentrations, and significantly different patterns of diurnal variation. Thus-in poorly ventilated buildings-indoor emission source strength is considered a more significant influence on VOC concentrations than infiltration of outdoor air. In the six smoking homes studied, environmental tobacco smoke (ETS) was found to make a substantial contribution to concentrations of 1,3-butadiene. This finding was based on the significantly higher concentrations detected in smoking compared to nonsmoking homes, the significant correlation between 1,3-butadiene concentrations and those of 3-ethenylpyridine (an ETS marker), factor analysis, and the results of a source apportionment exercise based on ratios of 1,3-butadiene to 3-ethenylpyridine.

Depletion of plasma factor XIII prevents disseminated intravascular coagulation-induced organ damage

The impact of clot stability affecting the vasculopathy and tissue necrosis in Shwartzman reaction was investigated using plasma Factor XIII A2-depleted rabbit (FXIII-DR). Plasma Factor XIIIA2 (FXIIIA2) was depleted by infusion of the mono-specific goat anti-rabbit FXIIIA2 IgG. Generalized Shwartzman reaction (GSR) was induced by priming and challenged by i.v. injection of LPS and local Shwartzman reaction (LSR) was primed by intradermal injection of LPS and challenged by i.v. injection of LPS. Histological examination of the GSR animals showed, extensive thrombi accumulation in renal tubules and bilateral cortical necrosis of kidney in 8 out of 10 rabbits but none in the FXIII-DR. Fibrinogen levels were elevated to 3 approximately 4 fold at 24 h and lowered at 48 h whereas a steady rise was seen in the FXIII-DR. FDP levels in GSR animals were significantly elevated at 24 h and further increased at 48 h but only slightly elevated in the FXIII-DR. Examination of the LSR tissues after 48 h showed an acute onset of progressive cutaneous vascular thrombosis, purpura, and secondary hemorrhagic necrosis whereas neither fibrin deposit nor necrosis of tissue were detected in FXIII-DR despite of an early edema formation. Fibrinogen levels were also increased two fold at 24 h but returned to basal levels at 48 h in control LSR animals but not affected at all in FXIII-DR. These results suggest that during the severe inflammatory conditions such as sepsis, the fibrinolytic system is functionally sufficient to dissipate the pathogenic accumulation of disseminated intravascular clots and exudated fibrin clots if those clots were prevented from getting crosslinked in plasma.

Purification and characterization of protein methylase II from Helicobacter pylori

Protein methylase II (AdoMet:protein-carboxyl O-methyltransferase, EC 2.1.1.24) was identified and purified 115-fold from Helicobacter pylori through Q-Sepharose ion exchange column, AdoHcy-Sepharose 4B column, and Superdex 200 HR column chromatography using FPLC. The purified preparation showed two protein bands of about 78 kDa and 29 kDa molecular mass on SDS-PAGE. On non-denaturing gel electrophoresis, the enzyme migrated as a single band with a molecular mass of 410 kDa. In addition, MALDI-TOF-MS analysis and Superdex 200 HR column chromatography of the purified enzyme showed a major mass signal with molecular mass values of 425 kDa and 430 kDa, respectively. Therefore, the above results led us to suggest that protein methylase II purified from H. pylori is composed of four heterodimers with 425 kDa (4x(78+29)=428 kDa). This magnitude of molecular mass is unusual for protein methylases II so far reported. The enzyme has an optimal pH of 6.0, a K(m) value of 5.0x10(-6) M for S-adenosyl-L-methionine and a V(max) of 205 pmol methyl-(14)C transferred min(-1) mg(-1) protein.

Rhodiola sachalinesis induces the expression of inducible nitric oxide synthase gene by murine fetal hepatocytes (BNL CL.2)

We have examined the effect of the aqueous extract of Rhodiola sachalinensis root (RSE), a traditional herbal medicine, on nitric oxide (NO) synthesis in murine fetal hepatocytes (BNL CL.2) by measuring the stable end-product nitrite and the mRNA of inducible NO synthase (iNOS). Interferon-gamma (IFN-gamma) by itself failed to induce NO synthesis in BNL CL.2 cells. RSE also did not elicit NO synthesis at concentrations up to 1,000 microg/ml, but dose- and time-dependently induced NO synthesis in the presence of IFN-gamma in BNL CL.2 cells. Whereas RSE or IFN-gamma failed to induce detectable levels of iNOS mRNA, a combination of RSE and IFN-gamma markedly induced iNOS mRNA in BNL CL.2 cells. Thus, we found that RSE triggered IFN-gamma-primed BNL CL.2 cells to synthesize NO by inducing iNOS gene expression. The capability of RSE to induce NO synthesis might be related to the therapeutic efficacy of RSE on the liver diseases.

Expression of MAGE-1, -2, and -3 genes in gastric carcinomas and cancer cell lines derived from Korean patients

We investigated the expression of MAGE-1, -2, and -3 genes in tissues of 51 gastric carcinomas from Korean patients and in 11 gastric cancer cell lines established in Korea using reverse transcriptase-polymerase chain reaction along with immunohistochemical analyses and DNA sequencing. Among the 51 gastric carcinomas, MAGE-1, -2, and -3 genes were expressed in 16 (31%), 22 (43%), and 17 (33%), respectively, and 31 (60%) expressed at least one of the three genes. In contrast, none of the three MAGE genes were expressed in normal sites of gastric tissue from each cancer patient. Out of 11 gastric cancer cell lines, MAGE-1, -2, and -3 genes were expressed in two (18%), five (46%), and four (36%), respectively. According to the clinicopathological analysis, the expression of any of the three MAGE genes was not significantly correlated with several clinicopathological factors except histologic types (p= 0.067). Immunohistochemical analyses identified positive staining with monoclonal antibodies 77B and 57B specifically against MAGE-1 and -3 proteins, respectively, in nuclei and cytoplasms of cells in mRNA-positive tumor tissue. These findings suggest the possibility as a target for tumor-specific immunotherapy for Korean patients.

Synthesis and properties of dextran-linked ampicillin

Ampicillin was coupled to dextran of average molecular weight 9,000 or 81,200 via the cyanogen bromide method. The degree of drug substituted per glucose unit (DSG) was varied from 0.104 to 0.028 (by weight bases: 22.1-5.9%) depending on the ratio of the reactants. Water solubility of dextran-linked ampicillin increased compared with free ampicillin, and the solubility decreased as the amount of ampicillin substituted increased. Plasma concentration of ampicillin, which appeared after intravenous administration of dextran-linked ampicillin in rats, was higher than when free ampicillin was administered, and the more so, the higher the molecular weight of dextran. Plasma half-life of dextran-linked ampicillin was two times longer than that of free ampicillin in rats. Antibacterial activities of dextran-linked ampicillin were evaluated against Staphylococcus aureus, Bacillus substillis, and Escherichia coli at two concentration levels according to the cup-plate method by measuring the diameter of inhibition zone, which was comparable to that of free ampicillin.

Trochanteric rotational osteotomy for osteonecrosis of the femoral head

The rate of success of transtrochanteric rotational osteotomy for osteonecrosis of the femoral head may be improved if patients are preselected using MRI. We have used three criteria for selection for osteotomy (i) minor collapse of the infarcted area, loss of congruity or the crescent sign, without narrowing of the joint space or acetabular involvement (ii) patients younger than 55 years and with a painful hip (iii) patients with an intact area constituting an arc of more than 120 degrees between the central vertical line of the femoral head and the posterior or anterior margin of the necrotic portion as seen on a midsagittal MRI. Seventeen patients were selected, with a follow-up of more than 42 months. A bone scan four weeks after operation showed adequate perfusion of the proximal segment in all hips. The hip score of Merle d'Aubigné et al improved from 13.5 points before operation to 17.2 points at the latest follow-up. Further collapse of the femoral head did not occur. The use of MRI instead of plain radiographs for the selection of patients has improved the success rate of transtrochanteric rotational osteotomy.

Perfusion MR imaging in gliomas: comparison with histologic tumor grade

OBJECTIVE

To determine the usefulness of perfusion MR imaging in assessing the histologic grade of cerebral gliomas.

MATERIALS AND METHODS

In order to determine relative cerebral blood volume (rCBV), 22 patients with pathologically proven gliomas (9 glioblastomas, 9 anaplastic gliomas and 4 low-grade gliomas) underwent dynamic contrast-enhanced T2*-weighted and conventional T1- and T2-weighted imaging. rCBV maps were obtained by fitting a gamma-variate function to the contrast material concentration versus time curve. rCBV ratios between tumor and normal white matter (maximum rCBV of tumor / rCBV of contralateral white matter) were calculated and compared between glioblastomas, anaplastic gliomas and low-grade gliomas.

RESULTS

Mean rCBV ratios were 4.90 degrees +/- 1.01 for glioblastomas, 3.97 degrees +/- 0.56 for anaplastic gliomas and 1.75 degrees +/-1.51 for low-grade gliomas, and were thus significantly different; p <.05 between glioblastomas and anaplastic gliomas, p <.05 between anaplastic gliomas and low-grade gliomas, p <.01 between glioblastomas and low-grade gliomas. The rCBV ratio cutoff value which permitted discrimination between high-grade (glioblastomas and anaplastic gliomas) and low-grade gliomas was 2.60, and the sensitivity and specificity of this value were 100% and 75%, respectively.

CONCLUSION

Perfusion MR imaging is a useful and reliable technique for estimating the histologic grade of gliomas.

Octamer binding protein-1 is involved in inhibition of inducible nitric oxide synthase expression by exogenous nitric oxide in murine liver cells

Nitric oxide (NO) has diverse effects on immune responses and hepatic functions. In BNL CL.2 cells, the murine embryonic liver cells, inducible nitric oxide synthase (iNOS) mRNA expression appeared after 3 h of treatment with IFN-gamma and LPS. Interestingly, mRNA and protein expression of iNOS was down-regulated by sodium nitroprusside (SNP) and diethylamine dinitric oxide in a time- and dose-dependent manner, but not by H2O2. TNF-alpha gene expression was also dramatically reduced by SNP, but IL-6 gene expression was inhibited much less. IFN-gamma and LPS-induced chloramphenicol acetyltransferase activity of iNOS promoter constructs was inhibited by SNP. Electrophoretic mobility shift assay showed that SNP inhibited IFN-gamma plus LPS-induced Oct-1 binding activity, and the inhibition was reversed by DTT. Mutation in the Oct-1 site completely abolished iNOS promoter activity. In addition, supershift assay and Southwestern analysis demonstrated that the Oct-1 binding activity was inhibited by SNP. Taken together, these results indicate that NO suppresses IFN-gamma plus LPS-induced iNOS expression, and that Oct-1 is an important element in this process.

Proliferating trichilemmal tumors: CT and MR imaging findings in two cases, one with malignant transformation

We report the imaging findings in two patients with proliferating trichilemmal tumors. In the first patient, the tumor arose on the lower lip, a very unusual location for this type of tumor, and showed malignant transformation with metastasis to a regional lymph node. It was seen as a poorly marginated soft-tissue mass with isointense signal on T1-weighted MR images and hyperintense signal on T2-weighted images. Large areas of high signal intensity caused by necrosis were also found within the tumor on T2-weighted images. After i.v. administration of contrast material, the mass showed significant enhancement, with considerable portions remaining unenhanced. In the second patient, the tumor originated from a preexisting trichilemmal cyst and occurred in the hair-bearing area of the posterior part of the neck. CT scans showed a well-encapsulated cystic mass that contained multiple speckled calcifications in a wall of variable thickness. There were several foci of smooth soft-tissue elevations from the inner wall of the mass, which corresponded histologically to proliferating portions of trichilemmal cyst.

Development of pulmonary arteriovenous fistulas after bidirectional cavopulmonary shunt

BACKGROUND

A high incidence of pulmonary arteriovenous fistulas (PAVF) has been reported after bidirectional cavopulmonary shunt (BCPS) or total cavopulmonary shunt (TCPS; BCPS in patients with interrupted inferior vena cava). However, the definite diagnostic criteria or standard diagnostic modality of PAVF has not yet been defined. The goal of this study was to evaluate the diagnostic modalities and the prevalence of PAVF.

METHODS

We selected 10 patients with TCPS and 27 patients with BCPS. Lung perfusion scan, contrast echocardiogram, and pulmonary angiogram were performed. The results were compared among groups of patients and among each diagnostic modality.

RESULTS

All 10 patients with TCPS and 16 and 13 patients with BCPS showed positive results on contrast echocardiograms and lung scans, respectively. Six patients with TCPS and 4 patients with BCPS showed positive results on pulmonary angiograms. All patients with TCPS developed subclinical or clinical PAVF and 19 patients with BCPS developed subclinical PAVF and none of them had clinical PAVF during the short-term follow-up.

CONCLUSIONS

Most patients with bidirectional cavopulmonary anastomosis have subclinical evidence of right-to-left intrapulmonary shunting. This problem can be demonstrated with various diagnostic modalities.

Three-year follow-up of women with the sole diagnosis of depressive personality disorder: subsequent development of dysthymia and major depression

OBJECTIVE

The authors sought to determine whether subjects with the sole diagnosis of depressive personality disorder are at higher risk for developing dysthymia and major depression than are healthy comparison subjects.

METHOD

Eighty-five women with depressive personality disorder who had no comorbid axis I or axis II disorders and 85 age-matched healthy comparison women were initially recruited and reinterviewed 3 years later to evaluate the cumulative incidence rate of dysthymia and major depression.

RESULTS

At the 3-year follow-up assessment, the women with depressive personality disorder had a significantly greater odds ratio for developing dysthymia than did the healthy comparison women. The difference in odds ratios for the development of major depression between women with and without depressive personality disorder did not reach statistical significance.

CONCLUSIONS

The present study, the first to determine the subsequent development of dysthymia and major depression in subjects with the sole diagnosis of depressive personality disorder, found that subjects with depressive personality disorder had a greater risk of developing dysthymia than did healthy comparison subjects at 3-year follow-up. Findings of the current study also suggest that depressive personality disorder may mediate the effects of a family history of axis I unipolar mood disorders.

A broad-spectrum caspase inhibitor blocks concanavalin A-induced hepatitis in mice

Fulminant hepatic failure (FHF) is a clinical syndrome resulting from massive death of liver cells or sudden and severe impairment of liver function. The causes of FHF are diverse and the overall mortality is very high. Recently, it became clear that apoptosis of hepatocytes is the critical cause of acute hepatic failure in FHF. It is well known that a family of cysteine proteases called caspase is one of the key mediators of the apoptotic pathway. Thus, caspases are attractive potential targets for the treatment of disorders resulting from excessive apoptosis. In this report, we examined the activity of a new caspase inhibitor, Xyz 033 mp. This nonpeptide inhibitor showed broad-spectrum caspase-inhibiting activity and protected primary rat hepatocytes from apoptotic death. In a mouse model of FHF induced by concavalin A (Con A), Xyz 033 mp suppressed elevated AST and ALT and specifically reduced IL-1 beta concentration. Also, Xyz 033 mp rescued mice from lethal experimental hepatitis induced by Con A. In addition, histological examinations indicated that Xyz 033 mp protected hepatocytes from the fatal apoptogenic effect of Con A. These results suggest that Xyz 033 mp may be a candidate therapeutic agent for FHF caused by massive apoptotic death of hepatocytes.

Helical CT angiography and three-dimensional reconstruction of total anomalous pulmonary venous connections in neonates and infants

OBJECTIVE

The objective of this study was to investigate the usefulness of helical CT angiography in the evaluation of total anomalous pulmonary venous connections.

MATERIALS AND METHODS

Fourteen patients with total anomalous pulmonary venous connections underwent helical CT angiography and subsequent three-dimensional (3D) reconstruction. They ranged in age from 3 days to 8 months (median age, 2.3 months) and in weight from 2.3 to 7.1 kg (median weight, 4.3 kg). The types of total anomalous pulmonary venous connections and the number of pulmonary veins were evaluated on axial and 3D images. Qualitative evaluations were performed for extent of pulmonary vascular enhancement and contrast- or motion-induced artifacts.

RESULTS

In all patients, helical CT angiography correctly depicted total anomalous pulmonary venous connections. Seven cases were the supracardiac type, four cases were the cardiac type, one case was the infracardiac type, and two cases were the mixed type. The detection rate of the pulmonary vein in 3D reconstruction images (95-98%) was slightly lower than that of the pulmonary vein in the axial images (100%), but the difference between axial and 3D reconstruction images was not statistically significant (p > 0.1). No statistically significant differences were noted among 3D reconstruction images in the detection rates of the pulmonary vein (p > 0.1). The extent of contrast enhancement of the pulmonary vein was good or excellent in all patients. In five patients, there were contrast-induced artifacts that made some surrounding vascular distortion but did not interfere with the pulmonary vein analysis, except in one patient. Motion-induced artifacts were observed in nine patients. One of them had an obstacle in pulmonary vein analysis.

CONCLUSION

The combination of axial and 3D images in helical CT angiography is helpful in the assessment of a total anomalous pulmonary venous connection containing the individual pulmonary vein, and this combination can be a good diagnostic tool in preoperative evaluation of neonates and infants with a total anomalous pulmonary venous connection.

Interfacial Aspects of Electrodeposited Carbon Fiber-Reinforced Epoxy Composites Using Monomeric and Polymeric Coupling Agents

Using a monomeric and two polymeric coupling agents, interfacial aspects of electrodeposited (ED) carbon fiber/epoxy composites were investigated by means of fragmentation techniques and acoustic emission (AE). ED results for dipped and untreated fibers under dry and wet conditions were compared. Multifiber-embedded composites (MFC) were prepared for direct comparison. Various treating conditions such as treating time, concentration of coupling agent, and treating temperature were optimized, respectively. The adsorption mechanisms of the coupling agents onto the carbon fiber were analyzed in terms of the electrolyte molecular interactions during ED process, due to chain mobility in the aqueous solution. The microfailure mechanisms occurring from fiber breaks, and matrix and interlayer cracks were examined by AE parameters. The interfacial shear strength (IFSS) of ED-treated carbon fibers was much higher than that of the other two cases under dry and wet conditions. Well-separated AE groups were found for the untreated, the dipped, and the ED-treated cases, and significantly more AE events occurred from the ED interlayer failure between fiber and matrix than from the untreated and even than from the dipping cases. AE events from different-type interlayers may be correlated with IFSS based on the differing mechanical and chemical roles of the interlayers. Copyright 2000 Academic Press.

Donor and recipient leukocytes in organ allografts of recipients with variable donor-specific tolerance: with particular reference to chronic rejection

We have attributed organ engraftment to clonal exhaustion-deletion of host-versus-graft and graft-versus-host reactions that are reciprocally induced and governed by migratory donor and recipient leukocytes. The so-called donor passenger leukocytes that migrate from the allograft into the recipients have been thoroughly studied (chimerism), but not the donor leukocytes that remain in, or return to, the transplanted organ. Therefore, using flow cytometry we determined the percentage and lineages of donor leukocytes in cell suspensions prepared from Lewis (LEW) cardiac allografts to 100 days posttransplantation. The LEW hearts were transplanted to naïve untreated Brown Norway (BN) recipients (group 2), to naïve BN recipients treated with a 28-day or continuous course of tacrolimus (TAC) (groups 3 and 4), and to drug-free BN recipients pretolerized by earlier bone marrow cell (BMC) or orthotopic LEW liver transplantation (groups 5 and 6). The findings in the heart cell suspensions were correlated with the results from parallel histopathologic-immunocytochemical studies and other studies of the grafts and of host tissues. Although the LEW heart allografts were rejected in 9.6 days by the unmodified recipients of group 2, all beat for 100 days in the recipients of groups 3 through 6. Nevertheless, all of the long-surviving cardiac allografts (but not the isografts in group 1) were the targets of an immune reaction at 5 days, reflected by dramatic increases in the ratio of leukocytes to nonleukocyte nucleated cells from normal values of 1:5-1:6 to 1:1-5:1 and by manifold other evidence of a major inflammatory event. The acute changes returned to baseline by 100 days in the chronic rejection (CR) free hearts of groups 4 and 6, but not in the CR-afflicted hearts of short-course TAC group 3 or the less-severely damaged hearts of the BMC-prime group 5. The freedom from CR in groups 4 and 6 was associated with a large donor contribution to the intracardiac leukocyte population at 5 days (28.6% and 22% in the respective groups) and at 100 days (30.5% in group 4 and 8.4% in group 6) compared with 2% and 1.2% at 100 days in the CR-blighted allografts of the partially tolerant animals of groups 3 and 5. Whether large or small, the donor leukocyte fraction always included a subset of class II leukocytes that had histopathologic features of dendritic cells. These class II(+) cells were of mixed myeloid (CD11b/c(+)) and lymphoid lineages; their migration was markedly inhibited by TAC and accelerated by donor-specific priming and TAC discontinuance. Although a large donor leukocyte population and a normal leukocyte/nonleukocyte cell ratio were associated with freedom from CR, these findings and the lineage profile of the intracardiac leukocytes were not associated with tolerance in the animals of groups 3 and 4 under active TAC treatment. The findings in this study, singly and in their entirety, are compatible with our previously proposed leukocyte migration-localization paradigm of organ allograft acceptance and tolerance.

REP1, a basic helix-loop-helix protein, is required for a branch pathway of phytochrome A signaling in arabidopsis

Phytochromes are primary photoreceptors mediating diverse responses ranging from induction of germination to floral induction in higher plants. We have isolated novel recessive rep1 (reduced phytochrome signaling 1) mutants, which exhibit a long-hypocotyl phenotype only under far-red light but not under red light. Physiological characterization showed that rep1 mutations greatly reduced a subset of phytochrome A-regulated responses, including the inhibition of hypocotyl elongation, cotyledon expansion, modulation of gravitropic growth of hypocotyl, and induction of the CAB (encoding chlorophyll a/b binding protein) gene, without affecting the accumulation of anthocyanin, far-red-preconditioned blocking of greening, induction of germination, and induction of CHS (encoding chalcone synthase) and FNR (encoding ferredoxin-NADP(+) oxidoreductase) genes. These results suggest that REP1 is a positive signaling component, functioning in a branch of the phytochrome A signaling pathway. Molecular cloning and characterization of the REP1 gene revealed that it encodes a light-inducible, putative transcription factor containing the basic helix-loop-helix motif.

Synergistic cooperation between water-soluble chitosan oligomers and interferon-gamma for induction of nitric oxide synthesis and tumoricidal activity in murine peritoneal macrophages

The effects of water-soluble chitosan oligomers (WSCO) on the synthesis of nitric oxide (NO) by murine peritoneal macrophages and on macrophage-mediated cytotoxicity towards murine fibrosarcoma Meth A cells were investigated. WSCO alone had no effect on NO synthesis and killing of tumor cells. However, treatment of macrophages with a combination of WSCO and interferon-gamma (IFN-gamma) synergically increased NO synthesis and enhanced killing of tumor cells. The synergism between IFN-gamma and WSCO in NO synthesis and tumoricidal activity was mainly dependent on increased secretion of tumor necrosis factor-alpha by WSCO.