Apparent zero-order kinetics of phenol biodegradation by substrate-inhibited microbes at low substrate concentrations

The reaction kinetics for phenol biodegradation at low substrate concentrations can be estimated based on the analysis of changes in the dissolved oxygen concentration in the bulk liquid during biodegradation. The measured oxygen concentration changes with an interesting behavior as biodegradation proceeds. The oxygen concentration in the bulk liquid decreases rapidly in the early stages of degradation and subsequently decreases linearly and then rapidly recovers to the initial saturated level. Taking into account the oxygen transfer rate between gas and liquid phases and oxygen consumption rate by microbes, the change in the dissolved oxygen concentration can be simulated with an unsteady state mass balance equation and three kinetic models for the rate of phenol metabolism: a substrate-inhibited model; a zero-order model; and a combined model. In the combined model, it is assumed that, at phenol concentrations above 10 mg/L, the degradation rate is expressed by a substrate-inhibited model; whereas at concentrations below 10 mg/L the zero-order model is applied. It was found that the characteristics of the change in the dissolved oxygen concentration, especially the rapid increase at the end of degradation, can only be described by the combined kinetic model. This result suggests that conventional Haldane-type kinetics would be unsuitable for estimating the phenol consumption rate at low phenol concentrations, in particular, at concentrations less than 10 mg/L.

Direct effects of protein S in ameliorating acute lung injury

OBJECTIVE

Protein S may exert an anticoagulant activity by enhancing the anticoagulant activity of activated protein C and/or by directly inhibiting the prothrombinase complex. Protein S itself may also directly regulate inflammatory responses and apoptosis. The role of protein S in acute lung injury (ALI) was unknown. This study evaluated the effect of protein S on ALI in the mouse.

METHODS

Animal ALI was induced in C57/BL6 mice by intratracheal instillation of lipopolysaccharide (LPS). Mice were treated with protein S or saline by intraperitoneal injection 1 h before LPS instillation.

RESULTS

Activated protein or protein S alone and combined activated protein C + protein S therapy decreased inflammatory markers and cytokines in mice with acute lung injury. In LPS-treated mice compared with controls ALI was induced as shown by significantly increased levels of total protein, tumor necrosis factor-alpha, interleukin-6 and monocyte chemoattractant protein-1 in the bronchoalveolar lavage fluid. Mice with ALI treated with protein S had significantly decreased concentrations of tumor necrosis factor-alpha and interleukin-6 in the lung compared with untreated animals. Thrombin-antithrombin III, a marker of the activity of the coagulation cascade, was unchanged. Protein S inhibited the expression of cytokines in vitro and increased activation of the Axl tyrosine kinase pathway in A549 epithelial cells.

CONCLUSION

Protein S protects against LPS-induced ALI, possibly by directly inhibiting the local expression of inflammatory cytokines without affecting coagulation.

Mucin-induced apoptosis of monocyte-derived dendritic cells during maturation

Many tumors arising from epithelial tissues produce mucins, which readily come into contact with infiltrating cells in cancer tissues. MUC2 mucins were purified from the conditioned medium of a colorectal cancer cell line, LS180 cells. It is known that in cancer patients, the number of dendritic cells (DCs) is reduced and their function is impaired. Mature DCs were generated from human peripheral blood monocytes through successive treatments with GM-CSF and IL-4, and then with proinflammatory mediators. When monocytes were cultured in the presence of MUC2 mucins in addition to GM-CSF and IL-4 at an early stage of development, mature DCs expressing CD83 decreased and apoptotic cells increased in a dose-dependent manner. During the development of DCs, sialic acid-binding Ig-like lectin (Siglec)-3 was constantly expressed. We prepared recombinant soluble Siglec-3 corresponding to the ectodomain of Siglec-3 and confirmed the binding of soluble Siglec-3 to the MUC2 mucins, probably through alpha2,6-sialic acid-containing O-glycans including a sialyl Tn antigen, which is known to bind to Siglec-3. Apoptosis was partially inhibited by anti-Siglec-3 mAb or recombinant soluble Siglec-3. These results suggest that apoptosis was partially induced through the ligation of the MUC2 mucins with Siglec-3.

Excitation of acoustic waves from cylindrical polyvinylidene fluoride (PVDF) film confined in a concentric wall

This paper investigates acoustic wave radiation from cylindrical polyvinylidene fluoride (PVDF) film mounted inside a concentric wall with a small air gap. In such a structure, propagation is allowed only in the gap between the film and the wall surface, and the wave propagates in the axial direction of the cylinder. The radiation impedance of the cylindrical transducer inside the concentric wall has been calculated using a one-dimensional propagation model. After calculating the mechanical impedance of the cylindrical PVDF film, the generated acoustic wave has been calculated as a function of frequency with various air gaps between the PVDF film and the wall. It has been found that the excited acoustic wave becomes stronger for a narrower air gap and shows a maximum at a specific air gap. This phenomenon has been explained as the match between the transducer impedance and the radiation impedance of the air gap. When the gap is too small, the radiation impedance exceeds the transducer's mechanical impedance, the acoustic wave radiation decreases with the decreasing gap, and the resonance frequency increases due to loading by the imaginary part of the excessive radiation impedance. All these theoretical results have been experimentally confirmed.

Down-modulation of B cell signal transduction by ligation of mucins to CD22

Epithelial cancer cells secrete mucins carrying carbohydrate antigens such as a sialyl-Tn antigen into cancer tissues and/or the bloodstream, in which mucins may interact with CD22 (Siglec-2). Mucins isolated from colon cancer cells and bovine submaxillary mucins bound to CD22 cDNA transfectants and a human B cell line, Daudi cell, and the binding of soluble recombinant CD22 to the mucins was confirmed by means of a plate assay. The binding specificity was demonstrated by the fact that the mucins bound to the recombinant CD22 with an intact ectodomain but not to that with a mutated ectodomain. Daudi cells were stimulated with anti-IgM F(ab')(2) in the presence or absence of mucins. Ligation of mucins to CD22 decreased the phosphorylation of CD22 and SHP-1 recruitment, and the phosphorylation of ERK-1/2 prominently. The in vivo effect of mucins on splenic B cells in the tumor-bearing state was investigated using mucin-producing (TA3-Ha) and non-producing (TA3-St) mammary adenocarcinoma-bearing mice. When fluorescence-labeled epiglycanins were administered to normal mice, a portion of them was taken up by the spleen and became associated with splenic B cells. We found that splenic B cells were reduced in TA3-Ha-bearing mice but not in TA3-St-bearing ones. These results suggest that in the tumor-bearing state a portion of the mucins in the bloodstream was taken up by the spleen and ligated to CD22 expressed on splenic B cells, which may have led to down-regulation of signal transduction.

Arsenic in various foods: Cumulative data

Data for the arsenic content in various foods were collated. The number of collected values was about 2500 columns, which enables an estimation of the range of arsenic contents in each food group. Data were categorized into six groups (crops, milk/meat/egg, fish, algae, seafood, others) and expressed as a percentile graph. In addition, the inorganic arsenic ratio of each food group was estimated. This approach enabled the authors to understand the arsenic contents of some food groups at a glance. The intake of inorganic arsenic seems to be mostly from seafood. The contribution from other categories of food is small.

Measurement of salivary adiponectin levels

We designed a method for measuring salivary adiponectin. In 188 healthy males, salivary adiponectin levels were measured using a commercial enzyme immunoassay kit for plasma with minor modifications. Intra- and inter-assay coefficients of variation for salivary adiponectin ranged from 0.6 to 4.9 and 1.1 to 9.8%, respectively. Salivary adiponectin levels ranged from 0.37 to 6.42 ng/ml, exceeding the kit's detection limit. For the over-43 age group, there was a significant correlation between plasma and salivary adiponectin levels (p<0.000001). These findings suggest the possibilities of salivary adiponectin as a marker of increased risk of non-insulin-dependent diabetes mellitus or cardiovascular disease.

Overproduction of PGE2 in peripheral blood monocytes of gastrointestinal cancer patients with mucins in their bloodstream

When monocytes from healthy donors were cultured in the presence of sera from patients with gastrointestinal cancer, PGE2 production from the monocytes was elevated. Serum proteins were fractionated on Sepharose 4B and the inducing activity was found in the excluded fractions. By excluding some mucins from the serum, the inducing activity was reduced effectively. The activity was also reduced by adding binding inhibitors to the scavenger receptor. These results suggest that peripheral blood monocytes in epithelial cancer patients may be continuously stimulated by mucins in the bloodstream through the scavenger receptor, resulting in overproduction of PGE2.

Different Progression of Tumor Xenografts between Mucin-Producing and Mucin–Non-Producing Mammary Adenocarcinoma-Bearing Mice

Previously, we found that MUC2 mucins could activate monocytes/macrophages through a scavenger receptor leading to cyclooxygenase (COX) 2 induction and overproduction of prostaglandin E2 (PGE2). To investigate the role of mucins in the tumor-bearing state, we compared s.c. tumor formation by using mucin-producing (TA3-Ha) and mucin-non-producing (TA3-St) cloned variants of mouse mammary adenocarcinomas. Expression of COX2 mRNA and protein and production of PGE2 were elevated in peritoneal macrophages stimulated with epiglycanin, which is a mucin-like glycoprotein produced by TA3-Ha cells. S.c. tumor tissues comprising TA3-Ha cells grew much faster than tissues comprising TA3-St cells. COX2 protein and vascular endothelial growth factor in TA3-Ha tumor tissues were elevated compared with the TA3-St tumor tissues. Although similar numbers of macrophages were observed immunochemically in the two types of tumor tissues, COX2 was induced prominently in the infiltrating macrophages in TA3-Ha tumor tissues but only faintly in TA3-St tumor tissues. Furthermore, angiogenesis progressed remarkably in TA3-Ha tumor tissues but only slightly in TA3-St tumor tissues. Epiglycanin-induced overproduction of PGE2 down-regulated interleukin-12 production by macrophages. IFN-gamma-producing CD4 T cells in spleens obtained from TA3-Ha tumor-bearing mice were significantly reduced compared with TA3-St tumor-bearing mice, suggesting that mucins cause PGE2-mediated immune suppression. Actually, the tumor growth of a TA3-Ha cell xenograft was suppressed effectively by oral administration of a COX2 inhibitor but that of a TA3-St cell one was not. These results suggest that mucins play an important role in tumor progression through overproduction of PGE2.

Effect of coffee intake on blood flow and maternal stress during the third trimester of pregnancy

OBJECTIVE

To investigate the effects of maternal ingestion of an ordinary dose of coffee on maternal stress and placental and fetal blood circulation during the third trimester of pregnancy.

METHODS

We performed a Doppler blood flow analysis for 10 women in the third trimester of pregnancy before and after they drank a cup of coffee. Salivary samples were collected from the 10 pregnant women and 14 nonpregnant controls just before coffee intake and 30 min later. Salivary cortisol levels and chromogranin A titers were determined.

RESULTS

Coffee intake had no effect on maternal or fetal blood flow. Among the pregnant women, Salivary cortisol levels were significantly reduced after coffee intake but salivary chromogranin A concentration was not significantly different before and after coffee intake.

CONCLUSION

The reduced salivary cortisol levels suggest that coffee intake decreases maternal stress during pregnancy.

Enhanced production of interleukin 6 in peripheral blood monocytes stimulated with mucins secreted into the bloodstream

PURPOSE

It has been reported that tumor progression is correlated with the serum level of interleukin 6 (IL-6). The purpose of this study was to investigate by what mechanism, other than production from tumor cell, the serum level of IL-6 is elevated in the tumor-bearing state.

EXPERIMENTAL DESIGN

Monocytes from healthy donors were cultured in the presence of sera from colon cancer patients, and the activity to elevate IL-6 production was estimated. This activity of serum was also examined after various biochemical treatments.

RESULTS

When monocytes from healthy donors were cultured in the presence of sera from patients with colon cancer, secretion of IL-6 from the cells was markedly elevated. Serum proteins were fractionated on Sepharose 4B and the activity to elevate IL-6 production was found in the excluded fractions. Sialyl Tn antigen was detected in these same fractions. By excluding some mucins from the serum, the inducing activity was reduced to 40% of the original level. Furthermore, we purified mucins from the conditioned medium of colon cancer cells. Production of IL-6 was effectively elevated by a small amount of purified mucins in a dose-dependent manner. When the inducing activity was examined in the presence of binding or competitive inhibitors to the scavenger receptor, the effect was remarkably reduced.

CONCLUSIONS

Mucins secreted from colon cancer cells into the bloodstream induce production of IL-6 in peripheral blood monocytes through the scavenger receptor, which may be responsible for the high level of serum IL-6 in colon cancer patients.

Heparan sulphate proteoglycans interact with neurocan and promote neurite outgrowth from cerebellar granule cells

We found that neurocan, a major brain chondroitin sulphate proteoglycan, interacts with HSPGs (heparan sulphate proteoglycans) such as syndecan-3 and glypican-1. Binding of these HSPGs to neurocan was prevented by treatment of the HSPGs with heparitinases I and II, but not by treatment of neurocan with chondroitinase ABC. Scatchard plot analysis indicated that neurocan has two binding sites for these HSPGs with different affinities. It is known that neurocan in the rodent brain is proteolytically processed with aging into N- and C-terminal fragments. When a mixture of whole neurocan and N- and C-terminal fragments prepared from neonatal mouse brains or recombinant N- and C-terminal fragments was applied to a heparin column, the whole molecule and both the N- and C-terminal fragments bound to heparin. A centrifugation cell adhesion assay indicated that both the N- and C-terminal neurocan fragments could interact with these HSPGs expressed on the cell surface. To examine the biological significance of the HSPG-neurocan interaction, cerebellar granule cells expressing these HSPGs were cultured on the recombinant neurocan substrate. A significant increase in the rate of neurite outgrowth was observed on the wells coated with the C-terminal neurocan fragment, but not with the N-terminal one. Neurite outgrowth-promoting activity was inhibited by pretreatment of neurocan substrate with heparin or the addition of heparitinase I to culture medium. These results suggest that HSPGs such as syndecan-3 and glypican-1 serve as the cell-surface receptor of neurocan, and that the interaction of these HSPGs with neurocan through its C-terminal domain is involved in the promotion of neurite outgrowth.

Intractable malleolar bursitis treated with lateral calcaneal artery adipofascial flap

Infections of the malleolar bursa, which is an adventitious bursa, rarely progress to intractable infectious bursitis. We present two cases of intractable malleolar bursitis. We performed successful transplantation of the lateral calcaneal artery adipofascial flap that resulted in healing of the bursitis. We discuss classification of bursae, treatments for bursitis and characteristics of the lateral calcaneal artery adipofascial flap.

Induction of cyclooxygenase-2 in monocyte/macrophage by mucins secreted from colon cancer cells

Up-regulation of cyclooxygenase-2 (COX-2) and overproduction of prostaglandins have been implicated in the initiation and/or progression of colon cancer. However, it is uncertain in which cells and how COX-2 is induced initially in the tumor microenvironment. We found that a conditioned medium of the colon cancer cell line, LS 180, contained a factor to induce COX-2 in human peripheral blood mononuclear cells. This factor was purified biochemically and revealed to be mucins. A small amount of mucins (approximately 100 ng of protein per ml) could elevate prostaglandin E2 production by monocytes. The mucins induced COX-2 mRNA and protein levels of monocytes in a dose- and time-dependent manner, indicating a COX-2-mediated pathway. We also have examined immunohistochemically the localization of COX-2 protein and mucins in human colorectal cancer tissues. It is noteworthy that COX-2-expressing macrophages were located around the region in which mucins were detectable, suggesting that COX-2 also was induced by mucins in vivo. These results suggest that mucins produced by colon cancer cells play a critical role in the initial induction of COX-2 in the tumor microenvironment.

Analysis of sequential immunoglobulin E-binding epitope of Japanese cedar pollen allergen (Cry j 2) in humans, monkeys and mice

BACKGROUND

Japanese cedar (Cryptomeria japonica; CJ) pollinosis has been reported to occur naturally in Japanese monkeys (Macaca fuscata) as well as in humans. Most human patients and monkeys with pollinosis have specific IgE for Cry j 2, a major allergen of CJ pollen.

OBJECTIVE

The main purpose of this study was to identify IgE B cell epitopes of Cry j 2 using a synthetic peptide in humans, monkeys and mice.

METHODS

We synthesized 38 overlapping peptides that span the entire length of Cry j 2. We examined the B cell epitopes of Cry j 2 that are recognized by IgE in the sera of human patients and monkeys with pollinosis and immunized mice using synthetic peptides of Cry j 2. We also examined the reaction of Cry j 2-specific mouse monoclonal IgG antibodies to the peptides. Furthermore, we conducted a histamine release assay with leucocytes from a pollinosis patient using human serum albumin (HSA) conjugated with the peptides as a B cell epitope.

RESULTS

We found that 16 of the 20 pollinosis patients who had specific IgE to Cry j 2 also exhibited IgE reaction with some Cry j 2 peptides. Of these 16 patients, 10 exhibited IgE reaction with Cry j 2 peptide no. 13 (121GQCKWVNGREICNDRDRPTA140). Five of the seven monkeys with CJ pollinosis exhibited a reaction with peptide no. 13. Furthermore, IgE in mice immunized with Cry j 2 and two mouse monoclonal IgG antibodies reacted with peptide no. 13. Peptide no. 13-conjugated HSA showed the release of histamine from basophils. Furthermore, to determine the minimum epitope in peptide no. 13, we conducted an enzyme-linked immunosorbent assay inhibition test. The core of the epitope in humans, monkeys and mice was 124KWVNGREI131.

CONCLUSION

We found that 124KWVNGREI131 is an important B cell epitope recognized by IgE in humans, monkeys and mice.

Contrasting patterns of genetic variation in the two sympatric geckos Gekko tawaensis and G. japonicus (Reptilia: Squamata) from western Japan, as revealed by allozyme analyses

Allozyme variation in two congeneric sympatric geckos, Gekko tawaensis and G. japonicus, from western Japan was examined. These species show similar densities and spatial arrangements of populations in this region, and their genetic structures are thus expected to have been formed under the influences of comparable geohistorical, environmental, and demographic factors. Results of the analyses, however, revealed strikingly different genetic patterns in the two species. Populations of G. tawaensis invariably showed a remarkably lowered heterozygosity (0-0.017) compared to G. japonicus (0.089-0.124). On the other hand, the genetic heterogeneity among populations is much greater in G. tawaensis (F(ST)=0.726) than in G. japonicus (F(ST)=0.101). The Mantel test failed to detect any significant correlations between log (estimated migration rate) and log (geographic distance) in either species, or between matrices of interpopulation pairwise F(ST) for the two species. These results suggest that, in each species, formation of the current genetic structure in western Japan has been chiefly influenced by stochastic factors, rather than the geohistorical architecture of this region. The high F(ST) and low heterozygosity in G. tawaensis suggest the effects of severe local fragmentation. On the other hand, the relatively low F(ST) and high heterozygosity in G. japonicus imply extensive gene flow among populations. Absence of significant correlations between the estimated migration rate and geographic distance in G. japonicus may suggest that such gene flow is promoted by human-mediated transport of this primarily house-dwelling lizard.

Immunologic tolerance maintained by CD25+ CD4+ regulatory T cells: their common role in controlling autoimmunity, tumor immunity, and transplantation tolerance

There is accumulating evidence that T-cell-mediated dominant control of self-reactive T-cells contributes to the maintenance of immunologic self-tolerance and its alteration can cause autoimmune disease. Efforts to delineate such a regulatory T-cell population have revealed that CD25+ cells in the CD4+ population in normal naive animals bear the ability to prevent autoimmune disease in vivo and, upon antigenic stimulation, suppress the activation/proliferation of other T cells in vitro. The CD25+ CD4+ regulatory T cells, which are naturally anergic and suppressive, appear to be produced by the normal thymus as a functionally distinct subpopulation of T cells. They play critical roles not only in preventing autoimmunity but also in controlling tumor immunity and transplantation tolerance.

Phase-matched air ultrasonic transducers using corrugated PVDF film with half wavelength depth

A new type of large area PVDF film air transducer is proposed. The transducer features a high power output and a sharp beam angle. Conventionally known curved length mode resonators with two clamps at both ends have a resonance frequency determined by the curvature. In the present work, PVDF was formed into alternating concave and convex multiple curved sections, eliminating clamps, i.e., a periodic corrugation structure using a single PVDF film. Each convex and concave section has a common resonance frequency. A common excitation voltage induces vibration for each section, and the vibration direction is normal to the film surface. The vibration phase of convex section is shifted 180 degrees from the concave section. These waves add constructively to form a strong acoustic beam when corrugation height is approximately one-half of the wavelength. The corrugation height controls propagation path difference, canceling excitation phase difference. The design principle based on a uniform vibration mode is presented. Experimental investigations using 8.8 x 2.5-, 10 x 5-, and 20 x 20-cm2 transducers are presented. Side lobes unique to this corrugation structure have been observed. A theoretical analysis of the side lobes is also presented. According to the theory, choosing the corrugation height appropriately will reduce side lobes to -15 dB with regard to the main lobe, and the observed side lobe height agreed with the theoretical result.

Increase of oligodendrocyte progenitor cells after spinal cord injury

The reaction of oligodendrocyte progenitor cells (OPCs) after spinal cord injury (SCI) is poorly understood. In this study, we examined oligodendroglial reactions after contusion SCI in adult rats by immunohistochemistry. OPCs were identified by staining with monoclonal antibodies (mAbs) A2B5 and O4. Each of the A2B5-, O4-positive OPCs and galactocerebroside-positive oligodendrocytes dramatically increased in the lesion of the dorsal posterior funiculus. Bromodeoxyuridine (BrdU) incorporation studies showed that most O4-positive cells in the lesion were labeled with BrdU, suggesting that these OPCs were proliferative. In contrast, the expression of myelin basic protein was decreased in the lesion compared with controls that received laminectomy only. From the injured cord, OPCs were isolated by immunopanning with mAb A2B5. We observed an increased number of OPCs from the injured spinal cords compared with those isolated from controls and unoperated animals. After several days in culture, the OPCs from the lesion expressed galactocerebroside. These results suggest that OPCs are induced and can differentiate following SCI in the adult rat.

Usefulness of endoscopic ultrasonography (EUS) in diagnosing esophageal infiltration of thyroid cancer

Pre-operative evaluation of esophageal infiltration is sometimes difficult in patients with advanced thyroid cancer even with recent imaging modalities. We evaluated the accuracy of endoscopic ultrasonography (EUS) in diagnosing esophageal infiltration of thyroid cancer. Twenty-nine patients with advanced thyroid cancer underwent EUS and other imaging examinations before surgery. The diagnostic accuracy of EUS was compared with that of magnetic resonance imaging (MRI) and esophagography based on pathologic findings in 27 of the 29 cases. EUS clearly demonstrated the 5-layer structure of the esophageal wall. EUS detected cancer invasion into the muscularis propria of the esophagus correctly in 8 of 10 patients diagnosed pathologically with muscular infiltration. EUS was significantly more accurate than MRI and esophagography (88.9% vs 63.0% and 66.7%, respectively). The specificity of EUS was also significantly better than the specificities of MRI or esophagography (94.1% vs 58.8% and 64.7%, respectively). The sensitivity, positive predictive value and negative predictive value of EUS tended to be better than those of MRI and esophagography. EUS is useful in evaluating the esophageal infiltration of thyroid cancer. This method has the further advantage of detecting the exact depth of cancer invasion into the esophageal wall.