Octet spin fractions and the proton spin problem.

The relatively small fraction of the spin of the proton carried by its quarks presents a major challenge to our understanding of the strong interaction. Traditional efforts to explore this problem have involved new and imaginative experiments and QCD based studies of the nucleon. We propose a new approach to the problem that exploits recent advances in lattice QCD. In particular, we extract values for the spin carried by the quarks in other members of the baryon octet in order to see whether the suppression observed for the proton is a general property or depends significantly on the baryon structure. We compare these results with the values for the spin fractions calculated within a model that includes the effects of confinement, relativity, gluon exchange currents, and the meson cloud required by chiral symmetry, finding a very satisfactory level of agreement given the precision currently attainable.

Clinical characteristics classified by the serum KL-6 level in patients with organizing pneumonia.

BACKGROUND: The serum Krebs von der Lungen-6 (KL-6) level is a useful marker correlated with the severity of various interstitial lung diseases. There have been few reports about the clinical characteristics of organizing pneumonia (OP) associated with the serum KL-6 levels. OBJECTIVE: This study was performed to determine whether the serum KL-6 levels can help determine the optimal treatment for OP. DESIGNS: Patients diagnosed with OP by clinical, radiological and histopathological findings were retrospectively reviewed. The OP patients were classified into two groups based on their serum KL-6 levels: normal KL-6 and high KL-6 groups. The two groups were compared with regard to their clinical and radiological data and therapeutic response one month after the start of treatment. RESULTS: The clinical records of twenty-two patients diagnosed with OP were reviewed. The serum KL-6 level was elevated in 11 of the 22 patients. There were no obvious differences in the clinical data between the two groups, although patients in the normal KL-6 group tended to have a fever. There were no significant differences in the chest X-ray (CXR) score or computed tomography (CT) score between the two groups. The CXR scores were correlated with the serum KL-6 levels. At 1 month after the diagnosis, 11 patients who needed treatment with prednisolone were included in the high KL-6 group. CONCLUSIONS: Patients with normal KL-6 levels showed lower CXR and CT scores. The serum KL-6 level on admission is a useful marker to judge the need for corticosteroid treatment in OP patients.

Potential bioavailability of phosphorus in citrus orchard soil to Microcystis aeruginosa.

Algal blooms in eutrophic water bodies are controlled by inputs of phosphorus (P) as the growth-limiting nutrient. Runoff particulate P associated with soil from fields often predominates among P fractions. Here, an algal bioassay to investigate the potential bioavailability of particulate P in soil collected from a citrus orchard was conducted. Microcystis aeruginosa was cultured in medium containing soil as the sole source of P. The P in the soil was not notably solubilized after autoclaving. Analyses of chlorophyll-a, suspended solids, particulate organic carbon, and particulate organic nitrogen showed that M. aeruginosa could utilize some of the P present in the soil, perhaps that in particulate form, but this form of P was not sufficient to maintain optimum growth.

Central airway stenosis in a patient with autoimmune pancreatitis.

Autoimmune pancreatitis is a unique form of chronic pancreatitis characterised by a high-serum immunoglobulin (Ig)G4 concentration involving various extra pancreatic lesions. A 63-yr-old female with autoimmune pancreatitis complained of cough. Chest computed tomography revealed an irregular stenosis of the central airway, lung hilar and mediastinal lymph node swelling, and a marked thickness of the bronchovascular bundle. Bronchoscopic examination revealed an irregular tracheobronchial stenosis accompanied with an oedematous mucosa and engorged vessels. Lung hilar and mediastinal lymph node swelling, central airway stenosis and bronchoscopic findings remarkably resembled those of sarcoidosis. Bronchial biopsy specimens demonstrated diffuse infiltrations of plasma cells, lymphocytes and eosinophils with fibrosis. Immunostaining showed infiltration of several IgG4-positive plasma cells. The patient was treated with oral prednisolone at 1 mg x kg(-1) x day(-1) for pancreatic lesions. A month later, the lung lesions, including central airway stenosis, lung hilar and mediastinal lymph node swelling, and bronchovascular bundle thickness, had dramatically improved along with improvement of pancreatitis, thus indicating a close association between the two conditions. This is the first report of a patient with autoimmune pancreatitis showing central airway stenosis similar to that of sarcoidosis.

Pulmonary involvement of autoimmune pancreatitis.

BACKGROUND: A wide variety of systemic lesions have been seen in patients with autoimmune pancreatitis. The pulmonary involvement of autoimmune pancreatitis was analysed to clarify the clinicopathological features of pulmonary lesions in comparison with pulmonary sarcoidosis. MATERIALS AND METHODS: Nineteen patients had autoimmune pancreatitis and eight had pulmonary sarcoidosis. The symptoms, laboratory data, chest computed tomography, Gallium-67 scintigraphy, pulmonary function testing and bronchoscopy findings, including the histological IgG4-immunostaining and IgG subclasses in the bronchoalveolar lavage in autoimmune pancreatitis, were collected to compare them with pulmonary sarcoidosis. RESULTS: The serum total protein, IgG and IgG4 levels were found to be significantly elevated in comparison with pulmonary sarcoidosis. In autoimmune pancreatitis, 17 patients showed bilateral hilar lymphadenopathy, while eight showed pulmonary nodules on chest computed tomography. Eighteen of 19 patients on Gallium-67 scintigraphy showed accumulation spots in either the hilar or mediastinal lymph nodes. Six patients with pulmonary nodules demonstrated accumulation spots in the corresponding lesions on chest computed tomography. All eight patients with pulmonary sarcoidosis showed accumulation spots in either the hilar or mediastinal lymph nodes. Bronchoalveolar lavage IgG4 in autoimmune pancreatitis showed a significant increase in comparison with pulmonary sarcoidosis. The histological findings obtained by a transbronchial lung biopsy showed the infiltration of lymphocytes and plasma cells in the thickened interstitum and alveoli with IgG4-positive plasma cell infiltration in patients with autoimmune pancreatitis. CONCLUSION: IgG4 in the bronchoalveolar lavage was seen at remarkably increased levels and IgG4-positive plasma cells were identified in the pulmonary lesions of patients with autoimmune pancreatitis.

Modulation of mucus production by interleukin-13 receptor alpha2 in the human airway epithelium.

BACKGROUND: IL-13 induces goblet cell hyperplasia and mucus overproduction in airway epithelial cells. IL-13 receptor alpha2 (IL-13Ralpha(2)) has been suggested to act as a 'decoy receptor' in the airway epithelium by inhibiting the IL-13 signal. However, the regulatory mechanisms for mucus production by IL-13Ralpha(2) remain unclear. OBJECTIVE: The aim of this study was to examine the role of IL-13Ralpha(2) in goblet cell hyperplasia and mucus overproduction by IL-13. METHODS: Bronchi were obtained from patients who underwent a lung resection due to lung cancer or benign lung tumours. Normal human bronchial epithelial cells (NHBECs) were isolated and cultured using an air-liquid interface (ALI) method. RESULTS: The number of periodic acid-Schiff's (PAS)-positive cells, goblet cells and MUC5AC-positive cells increased after adding IL-13 into NHBECs. The concentrations of MUC5AC protein in the supernatant and the mRNA expression of MUC5AC significantly increased after adding IL-13, and returned to control levels at 21 days. The mRNA expression of IL-13Ralpha(2) significantly increased at 7 days and then continuously increased up to 21 days. The protein of a soluble form of IL-13Ralpha(2) in the supernatants significantly increased at 14 and 21 days. Anti-IL-13Ralpha(1) antibody and recombinant IL-13Ralpha(2) reduced the number of PAS-positive cells, goblet cells and MUC5AC-positive cells, and MUC5AC mRNA, while the anti-IL-13Ralpha(2) antibody increased the number of these cells and MUC5AC mRNA. The concentration of MUC5AC protein in the supernatant induced by IL-13 was reduced by anti- IL-13Ralpha(1) antibody and recombinant IL-13Ralpha(2). IL-13-induced signal transducer and activator of transcription (STAT) activation was inhibited by anti-IL-13Ralpha(1) antibody and recombinant IL-13Ralpha(2). In contrast, the IL-4-induced mucus production, mucus secretion and STAT activation were not inhibited by recombinant IL-13Ralpha(2). CONCLUSION: The soluble form of IL-13Ralpha(2) may therefore modulate mucus overproduction by IL-13 through the pathway including IL-13Ralpha(1) in NHBECs.

Transcriptome Reveals Cathepsin K in Periodontal Ligament Differentiation.

Periodontal ligaments (PDLs) play an important role in remodeling the alveolar bond and cementum. Characterization of the periodontal tissue transcriptome remains incomplete, and an improved understanding of PDL features could aid in developing new regenerative therapies. Here, we aimed to generate and analyze a large human PDL transcriptome. We obtained PDLs from orthodontic treatment patients, isolated the RNA, and used a vector-capping method to make a complementary DNA library from >20,000 clones. Our results revealed that 58% of the sequences were full length. Furthermore, our analysis showed that genes expressed at the highest frequencies included those for collagen type I, collagen type III, and proteases. We also found 5 genes whose expressions have not been previously reported in human PDL. To access which of the highly expressed genes might be important for PDL cell differentiation, we used real-time polymerase chain reaction to measure their expression in differentiating cells. Among the genes tested, the cysteine protease cathepsin K had the highest upregulation, so we measured its relative expression in several tissues, as well as in osteoclasts, which are known to express high levels of cathepsin K. Our results revealed that PDL cells express cathepsin K at similar levels as osteoclasts, which are both expressed at higher levels than those of the other tissues tested. We also measured cathepsin K protein expression and enzyme activity during cell differentiation and found that both increased during this process. Immunocytochemistry experiments revealed that cathepsin K localizes to the interior of lysosomes. Last, we examined the effect of inhibiting cathepsin K during cell differentiation and found that cathepsin K inhibition stimulated calcified nodule formation and increased the levels of collagen type I and osteocalcin gene expression. Based on these results, cathepsin K seems to regulate collagen fiber accumulation during human PDL cell differentiation into hard tissue-forming cells.

Crystallization and some properties of purine nucleoside phosphorylase from chicken liver.

Purine nucleoside phosphorylase (purine nucleoside:orthophosphate ribosyltransferase, EC 2.4.2.1) from chicken liver has been purified about 650 fold and crystallized. The crystalline enzyme was cube shaped and showed a specific activity of 46 units per mg of protein. The homogeneity of the crystalline enzyme was shown by polyacrylamide gel-disc electrophoresis. The sedimentation coefficient (s-degrees 2o,w) was 5.4 S. The crystalline enzyme was activated by the substrate inosine. The Hill coefficient was estimated to be 0.76, suggesting negative cooperativity with regard to the substrate inosine. The results of the kinetic analysis are consistent with the mechanism being a "rapid equilibrium random Bi-Bi reaction". The apparent equilibrium constant for phosphorolysis was 0.048.

Molecular properties and a nonidentical trimeric structure of purine nucleoside phosphorylase from chicken liver.

Some molecular properties of crystalline purine nucleoside phosphorylase (purine nucleoside: orthophosphate ribosyltransferase, EC 2.4.2.1) from chicken liver were investigated and discussed. The molecular weight of the native enzyme was determined to be 89 000 by gel filtration and sedimentation coefficient, and 90 000 by sedimentation equilibrium, respectively. The enzyme was assumed to be a trimer consisting of one large subunit and two identical small subunits. The molecular weights of two different sized subunits were determined to be 32 000 and 28 000 by sodium dodecyl sulfate gel electrophoresis, and 30 000 and 27 000 by 6 M guanidine hydrochloride gel filtration. The amino acid composition was determined and the partial specific volume was estimated to be 0.735 ml/g.

Cytosol 5'-nucleotidase from chicken liver. Purification and some properties.

1. 5'-Nucleotidase (5'-ribonucleotide phosphohydrolase, EC 3.1.3.5) from the cytosol of chicken liver has been purified 1860-fold with an overall yield of 20% by a combination of precipitation at pH 5.3, (NH4)2SO4 fractionation, calcium phosphate gel adsorption, phosphocellulose chromatography and gel filtration with Sephadex G-200. The enzyme has been shown to be highly purified, as judged by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. This is the first time it has been possible to obtain a purified 5'-nucleotidase from the cytosol of animal tissue. 2. An S20, W of 9.7 S for 5'-nucleotidase was obtained by the use of sucrose density gradient centrifugation and a Stokes radius of 5.1 nm was estimated by gel filtration techniques. From these values and the assumed partial specific volume of 0.725 cm3/g, the molecular weight of the enzyme was calculated to be 205 000. One major band, corresponding to a molecular weight of 51 000, was detected after sodium dodecyl sulphate-polyacrylamide gel electrophoresis indicating that the native enzyme was composed of four identical subunits. 3. Some properties of the purified enzyme, including pH optimum Mg2+ dependency and substrate specificity, resembled closely those of the partially purified enzyme from chicken liver acetone powder as reported by Itoh, R., Mitsui, A. and Tsushima, K. (1967) Biochim. Biophys. Acta 146, 151-159.

Effects of monovalent cations on AMP nucleosidase from Azotobacter vinelandii.

The effect of monovalent cations on the purified AMP nucleosidase (AMP phosphoribohydrolase, EC 3.2.2.4) from Azotobacter vinelandii was investigated. All the monovalent cations were activators of the enzyme: Rb+ and Cs+ were the most effective, followed by K+, Na+, NH4+ and Li+ in that order. The apparent Ka for MgATP and nH values (Hill's interaction coefficient) decreased from 0.9 to 0.1 mM, and from 4 to 1, respectively, with the increase in K+ concentration, suggesting that the cation effects are on MgATP binding rather than catalysis. Gel filtration studies have revealed that the enzyme forms a non-dissociable enzyme species with a Stokes radius of 6.0--6.2 nm in the presence of saturating concentrations of monovalent cations, which can be distinguished from the 5.5-nm enzyme species showing temperature-dependent dissociation of the molecule in sulfate or phosphate. These results suggest that these ligands affect the association of the subunits through changes in the environment of the hydrophobic side chains of the enzyme molecules.

Studies on chicken liver xanthine dehydrogenase with reference to the problem of non-equivalence of FAD moieties.

1. Reduction of chicken liver xanthine dehydrogenase (xanthine: NAD+ oxidoreductase, EC 1.2.1.37) by xanthine under anaerobic condition proceeded in two phases. This biphasicity may be due to functional and non-functional enzymes in the enzyme preparation. 2. Cyanolysis of a persulfide group of chicken liver enzyme resulted in an inactivation of the enzyme. The non-functional enzyme in the standard enzyme preparation was found to lack persulfide groups at the active sites. 3. The remaining NADH-Methylene Blue oxidoreductase activity, after KI treatment of the xanthine-reduced enzyme of a high flavin activity ratio, is not at the level of 50% of the initial activity, differing from the report suggesting non-equivalence of FAD chromophores. 4. The findings in the present report indicate that FAD chromophores of chicken liver enzyme are essentially equivalent.

The role of polyamines in the regulation of AMP deaminase isozymes.

The differential effects of polyamines on the activity of AMP deaminase isozyme A (from rat muscle) and isozyme B (from rat liver) are reported. Polyamines activate isozyme B but inhibit isozyme A.

AMP deaminase from baker's yeast. Purification and some regulatory properties.

AMP deaminase (AMP aminohydrolase, EC 3.5.4.6) was found in extract of baker's yeast (Saccharomyces cerevisiae), and was purified to electrophoretic homogeneity using phosphocellulose adsorption chromatography and affinity elution by ATP. The enzyme shows cooperative binding of AMP (Hill coefficient, nH, 1.7) with an s0.5 value of 2.6 mM in the absence or presence of alkali metals. ATP acts as a positive effector, lowering nH to 1.0 and s0.5 to 0.02 mM. P1 inhibits the enzyme in an allosteric manner: s0.5 and nH values increase with increase in Pi concentration. In the physiological range of adenylate energy charge in yeast cells (0.5 to 0.9), the AMP deaminase activity increases sharply with decreasing energy charge, and the decrease in the size of adenylate pool causes a marked decrease in the rate of the deaminase reaction. AMP deaminase may act as a part of the system that protects against wide excursions of energy charge and adenylate pool size in yeast cells. These suggestions, based on the properties of the enzyme observed in vitro, are consistent with the results of experiments on baker's yeast in vivo reported by other workers.

Chicken liver amidophosphoribosyltransferase. Ligand-induced alterations in molecular properties.

A homogeneous amidophosphoribosyltransferase (EC 2.4.2.14) preparation, which was sensitive to purine nucleotide inhibitors, was obtained from chicken liver. From the result of sodium dodecyl sulfate polyacrylamide gel electrophoresis, the subunit weight was estimated to be approximately 58 000. In Tris-HCl buffer, the predominant form of the enzyme had an S20,w of 6.5, Strokes radius of 40 A, and estimated molecular weight of 110 000. Incubation with 5-phosphoribosyl 1-pyrophosphate or Pi resulted in an increase in the S20,w to 9.1--9.5, Strokes radius 50 A, and estimated molecular weight to 200 000. Incubation of the large form with AMP led to a decrease in the molecular wight of the enzyme. It is concluded that chicken liver amidophosphoribosyltransferase is an allosteric protein whose activity is regulated by a series of conformational changes induced by a number of ligands.

Roles of P-selectin in inflammation, neointimal formation, and vascular remodeling in balloon-injured rat carotid arteries.

BACKGROUND: P-selectin plays key roles in mediating inflammation through promoting adherence of leukocytes to activated platelets and endothelium. This process is one of the initial events in atherosclerosis and restenosis after coronary angioplasty. METHODS AND RESULTS: Using a rat balloon-injury model, we examined the role of P-selectin in vascular inflammatory processes. In the acute phase, immunohistochemistry revealed that P-selectin was intensely expressed on both activated platelets covering the denuded segment and endothelial cells of the inflamed adventitial small vessels. Treatment with an anti-P-selectin monoclonal antibody (MAb) for 8 consecutive days significantly inhibited neointimal formation at day 14 (42% inhibition; P:<0.05), and this effect persisted at day 56 (40% inhibition; P:<0.01) compared with the control group. Vascular shrinking accompanying adventitial fibrosis was also attenuated at day 56. Inhibition of both neointimal formation and vascular shrinking resulted in the lumen area of the anti-P-selectin treatment group being approximately 3 times larger at day 56 than that of the control group. Accumulation of CD45-positive leukocytes in the developing neointima, media, and adventitia at day 8 was significantly inhibited by treatment with the anti-P-selectin MAb. Scanning electron microscopy demonstrated that anti-P-selectin treatment resulted in a less thrombogenic surface of the arterial intima, which featured a pseudoendothelial appearance at day 14 after injury. CONCLUSIONS: These results suggest that inhibition of P-selectin-mediated leukocyte recruitment prevents the development of neointimal formation, adventitial inflammation, and vascular shrinking and promotes pseudoendothelialization by luminal smooth muscle cells. This treatment thus beneficially affects vascular remodeling after balloon injury in rats.

PLAP-1/Asporin Regulates TLR2- and TLR4-induced Inflammatory Responses.

Periodontal ligament-associated protein 1 (PLAP-1)/asporin is an extracellular matrix protein preferentially expressed in periodontal ligaments. PLAP-1/asporin inhibits the cytodifferentiation and mineralization of periodontal ligament cells and has important roles in the maintenance of periodontal tissue homeostasis. However, the involvement of PLAP-1/asporin in inflammatory responses during periodontitis is poorly understood. This study hypothesized that PLAP-1/asporin might affect the pathogenesis of periodontitis by regulating periodontopathic bacteria-induced inflammatory responses. Proinflammatory cytokine expression induced by Toll-like receptor 2 (TLR2) and TLR4 was significantly downregulated when PLAP-1/asporin was overexpressed in periodontal ligament cells. Similarly, recombinant PLAP-1/asporin inhibited TLR2- and TLR4-induced proinflammatory cytokine expression in macrophages. We also confirmed that NF-κB activity induced by TLR2 and TLR4 signaling was suppressed by the addition of recombinant PLAP-1/asporin. Furthermore, IκB kinase α degradation induced by TLR4 was reduced by PLAP-1/asporin. Immunoprecipitation assays demonstrated the binding abilities of PLAP-1/asporin to both TLR2 and TLR4. Taken together, PLAP-1/asporin negatively regulates TLR2- and TLR4-induced inflammatory responses through direct molecular interactions. These findings indicate that PLAP-1/asporin has a defensive role in periodontitis lesions by suppressing pathophysiologic TLR signaling and that the modulating effects of PLAP-1/asporin might be useful for periodontal treatments.

PLAP-1/Asporin Positively Regulates FGF-2 Activity.

PLAP-1 is an extracellular matrix protein that is predominantly expressed in the periodontal ligament within periodontal tissue. It was previously revealed that PLAP-1 negatively regulates bone morphogenetic protein 2 and transforming growth factor ß activity through direct interactions. However, the interaction between PLAP-1 and other growth factors has not been defined. Here, we revealed that PLAP-1 positively regulates the activity of fibroblast growth factor 2 (FGF-2), a critical growth factor in tissue homeostasis and repair. In this study, we isolated mouse embryonic fibroblasts (MEFs) from Plap-1(-/-) mice generated in our laboratory. Interestingly, Plap-1(-/-) MEFs exhibited enhanced responses to bone morphogenetic protein 2 but defective responses to FGF-2, and Plap-1 transfection into Plap-1(-/-) MEFs rescued these defective responses. In addition, binding assays revealed that PLAP-1 promotes FGF-2-FGF receptor 1 (FGFR1) complex formation by direct binding to FGF-2. Immunocytochemistry analyses revealed colocalization of PLAP-1 and FGF-2 in wild-type MEFs and reduced colocalization of FGF-2 and FGFR1 in Plap-1(-/-) MEFs compared with wild-type MEFs. Taken together, PLAP-1 positively regulates FGF-2 activity through a direct interaction. Extracellular matrix-growth factor interactions have considerable effects; thus, this approach may be useful in several regenerative medicine applications.

Effects of changes in angiotensin converting enzyme activity on renin release: pretreatment with dexamethasone enhances a plasma renin activity response to captopril in normal subjects.

Healthy adults were given captopril (25 mg and 75 mg) po with or without dexamethasone (DXM) pretreatment (1 mg po 2 h before and simultaneously with the captopril). We determined the serum potassium and sodium concentrations, plasma prostaglandin E2 level, PRA, serum angiotensin converting enzyme (ACE) activity, and aldosterone level from 20 min before to 120 min after administration of captopril. DXM pretreatment stimulated the PRA response to captopril. This stimulation was suppressed by indomethacin. However, the administration of DXM did not induce a consistent rise in the prostaglandin E2 level. The administration of DXM induced a significant rise in the potassium concentration, but since simultaneous administration of indomethacin with captopril induced the suppression of PRA without affecting the potassium level, the PRA increase in response to captopril with DXM was not caused directly by the potassium increase. There were no significant differences in the PRA increase between 25 mg captopril and 75 mg captopril, or between DXM-25 mg captopril and DXM-75 mg captopril, though the inhibitions of ACE activity by captopril differed according to dose. The PRA increases, but not the captopril-induced inhibition of ACE activity, were significantly different between captopril alone and captopril with DXM pretreatment at either dose of captopril. Thus, the inhibition of ACE activity perhaps allows PRA to increase in response to captopril. These results suggest that the DXM stimulation of PRA may have been dependent on the inhibition of ACE activity by captopril.

Uterine leiomyosarcomas and benign smooth muscle tumors: usefulness of nuclear DNA patterns studied by flow cytometry.

Flow cytometry was used to determine the DNA ploidy pattern of paraffin-embedded archival tissue specimens from 90 surgically resected uterine smooth muscle tumors (49 leiomyosarcomas and 41 leiomyomas). The technique of Hedley was used for preparation of paraffin-embedded tissue into single dissociated nuclei, and the method of Vindeløv was used for staining with propidium iodide. Among the 41 leiomyomas, most tumors (88%) had a DNA diploid pattern; the exceptions were two DNA tetraploid/polyploid and three DNA aneuploid samples. The DNA histograms of the 49 leiomyosarcomas (including 6 epithelioid leiomyosarcomas) were classified as follows: 9 cases (18%) exhibited a DNA diploid pattern, 29 cases (59%) had a DNA tetraploid/polyploid pattern, and 11 cases (23%) had DNA aneuploid peaks. Although DNA ploidy pattern cannot be used diagnostically to distinguish malignant from benign uterine smooth muscle tumors, the nuclear DNA ploidy pattern is an easily measured, objective determination that may have important prognostic significance for patients with uterine leiomyosarcomas.