Assessing the progression of chronic periodontitis using subgingival pathogen levels: a 24-month prospective multicenter cohort study.

BACKGROUND: The diagnosis of the progression of periodontitis presently depends on the use of clinical symptoms (such as attachment loss) and radiographic imaging. The aim of the multicenter study described here was to evaluate the diagnostic use of the bacterial content of subgingival plaque recovered from the deepest pockets in assessing disease progression in chronic periodontitis patients. METHODS: This study consisted of a 24-month investigation of a total of 163 patients with chronic periodontitis who received trimonthly follow-up care. Subgingival plaque from the deepest pockets was recovered and assessed for bacterial content of Porphyromonas gingivalis, Prevotella intermedia, and Aggregatibacter actinomycetemcomitans using the modified Invader PLUS assay. The corresponding serum IgG titers were measured using ELISA. Changes in clinical parameters were evaluated over the course of 24 months. The sensitivity, specificity, and prediction values were calculated and used to determine cutoff points for prediction of the progression of chronic periodontitis. RESULTS: Of the 124 individuals who completed the 24-month monitoring phase, 62 exhibited progression of periodontitis, whereas 62 demonstrated stable disease. The P. gingivalis counts of subgingival plaque from the deepest pockets was significantly associated with the progression of periodontitis (p < 0.001, positive predictive value = 0.708). CONCLUSIONS: The P. gingivalis counts of subgingival plaque from the deepest pockets may be associated with the progression of periodontitis.

Salivary pathogen and serum antibody to assess the progression of chronic periodontitis: a 24-mo prospective multicenter cohort study.

BACKGROUND AND OBJECTIVE: A diagnosis of periodontitis progression is presently limited to clinical parameters such as attachment loss and radiographic imaging. The aim of this multicenter study was to monitor disease progression in patients with chronic periodontitis during a 24-mo follow-up program and to evaluate the amount of bacteria in saliva and corresponding IgG titers in serum for determining the diagnostic usefulness of each in indicating disease progression and stability. MATERIAL AND METHODS: A total of 163 patients with chronic periodontitis who received trimonthly follow-up care were observed for 24 mo. The clinical parameters and salivary content of Porphyromonas gingivalis, Prevotella intermedia and Aggregatibacter actinomycetemcomitans were assessed using the modified Invader PLUS assay, and the corresponding serum IgG titers were measured using ELISA. The changes through 24 mo were analyzed using cut-off values calculated for each factor. One-way ANOVA or Fisher's exact test was used to perform between-group comparison for the data collected. Diagnostic values were calculated using Fisher's exact test. RESULTS: Of the 124 individuals who completed the 24-mo monitoring phase, 62 exhibited periodontitis progression, whereas 62 demonstrated stable disease. Seven patients withdrew because of acute periodontal abscess. The ratio of P. gingivalis to total bacteria and the combination of P. gingivalis counts and IgG titers against P. gingivalis were significantly related to the progression of periodontitis. The combination of P. gingivalis ratio and P. gingivalis IgG titers was significantly associated with the progression of periodontitis (p = 0.001, sensitivity = 0.339, specificity = 0.790). CONCLUSIONS: It is suggested that the combination of P. gingivalis ratio in saliva and serum IgG titers against P. gingivalis may be associated with the progression of periodontitis.

Long-term entecavir therapy results in falls in serum hepatitis B surface antigen levels and seroclearance in nucleos(t)ide-naïve chronic hepatitis B patients.

Entecavir (ETV) is reported to result in suppression of hepatitis B virus DNA (HBV DNA) replication with minimal drug resistance. However, information on the long-term effect of such therapy on serum hepatitis B surface antigen (HBsAg) level and elimination of HBsAg is not available. ETV therapy was started in 553 nucleos(t)ide-naïve patients with chronic hepatitis B infection (HBeAg positive: 45%) in our hospital. Serum HBsAg levels were measured serially by the Architect assay. The median baseline HBsAg was 2180 IU/mL (0.12-243 000 IU/mL), and median follow-up period was 3.0 years, with 529, 475, 355, 247 and 163 patients followed-up for 1, 2, 3, 4 and 5 years, respectively. At year 5, the mean log HBsAg decline from baseline was -0.48 log IU/mL, and the cumulative HBsAg clearance rate was 3.5%. Multivariate analysis identified HBV DNA level at baseline (<3.0 log copies IU/mL, odd ratio = 10.2; 95% confidence interval = 1.87-55.5, P = 0.007) and HBsAg level (<500 IU/mL, odd ratio = 29.4; 95% confidence interval = 2.80-333, P = 0.005) as independent predictors of HBsAg seroclearance. These results indicate that although serum HBsAg level declines gradually during ETV therapy, HBsAg seroclearance remains a rare event.

Superselective intra-arterial cisplatin infusion and concomitant radiotherapy for maxillary sinus cancer.

BACKGROUND: The purpose of this study was to evaluate the efficacy of superselective cisplatin infusion with concomitant radiotherapy (RADPLAT) for previously untreated patients with the squamous cell carcinoma of maxillary sinus (SCC-MS). METHODS: Between 1999 and 2010, 54 patients were given superselective intra-arterial infusions of cisplatin (100-120 mg m(-2) per week) with simultaneous intra-venous infusions of thiosulfate to neutralise cisplatin toxicity and conventional radiotherapy (65-70 Gy). RESULTS: One patient (1.9%) was diagnosed with T2, 14 (25.9%) with T3, 27 (50%) with T4a, and 12 (22.2%) with T4b disease. Lymph-node involvement was present in 12 patients (22.2%). During the median follow-up period of 6.4 years, the 5-year local progression-free and overall survival rates were 65.8 and 67.9% for all patients, respectively. No patient died as a result of treatment toxicity or experienced a cerebrovascular accident. Osteonecrosis (n=5), brain necrosis (n=1), and ocular/visual problems (n=14) were observed as late adverse reactions. CONCLUSION: We have shown excellent overall survival and local progression-free rate in SCC-MS patients treated by RADPLAT with acceptable rates of acute and late toxicity. A multi-institutional trial is needed to prove that this strategy is a feasible and effective approach for the treatment of SCC-MS.

Virological response and safety of 24-week telaprevir alone in Japanese patients infected with hepatitis C virus subtype 1b.

Hepatitis C virus (HCV) subtype 1b, which infects approximately 70% of Japanese carriers, is likely to be more eradicable by a telaprevir regimen than subtype 1a because of the higher genetic barrier of Val(36) and Arg(155) substitutions. The aims of this exploratory study were to evaluate the virological response and safety of 24-week oral administration of telaprevir alone in chronic HCV subtype 1b infection. Fifteen treatment-naïve patients were treated with telaprevir 750 mg every 8 h for 24 weeks. All patients were Japanese whose median age was 58.0 years (range: 45-68), and six patients (40%) were men. Median baseline HCV RNA level was 6.80 log(10) IU/mL (range: 3.55-7.10). The HCV RNA levels decreased to undetectable in five patients (33%) within 8 weeks. Three patients (20%) with negative HCV RNA by Week 4 achieved end of treatment response. One patient (7%) who achieved sustained virological response had a low baseline viraemia of 3.55 log(10) IU/mL. Most of the adverse events including anaemia and skin disorders were mild to moderate. Developed variants were T54A and A156V/T/F/Y with or without secondary substitutions rather than V36M ± R155K. Telaprevir alone for 24 weeks in Japanese patients with HCV subtype 1b resulted in an sustained viral response rate of 7% (1/15) and was well tolerated for 24 weeks. These results will support the implementation of further studies on oral combination of telaprevir with other direct-acting antiviral agents in patients infected with HCV subtype 1b.

Safety, pharmacokinetics and resistant variants of telaprevir alone for 12 weeks in hepatitis C virus genotype 1b infection.

BACKGROUND: Telaprevir in combination with peginterferon and ribavirin is a promising advancement in chronic hepatitis C treatment. However, the safety, tolerability, pharmacokinetics and antiviral profiles of telaprevir alone beyond 2 weeks have not been studied. METHODS: In a phase 1b study in Japan, 10 treatment-naïve patients infected with hepatitis C virus genotype 1b with high viral load (>5 log(10) IU/mL) received telaprevir 750 mg every 8 h (q8h) for 12 weeks. We examined the safety, tolerability, pharmacokinetics, hepatitis C virus (HCV) RNA levels and resistant variants of telaprevir. RESULTS: Neither serious adverse events nor discontinuations of study drug owing to an adverse event occurred. The most common adverse drug reactions were rash (80%) and anaemia (70%). Telaprevir concentration reached its steady state within 2 days after the first administration without abnormal accumulation. Telaprevir alone provided potent antiviral activity: a median log(10) decrease of 2.325 at 16 h and 5.175 on Day 14. During the treatment, HCV RNA levels at the nadir were below the limit of the quantification in seven patients and undetectable in three of 10 patients. Viral breakthrough associated with mainly Ala(156) -substituted variants occurred in eight patients, and only one patient showed end-of-treatment response. The selected variants reverted to the wild-type during the 24-week follow-up period. CONCLUSION: Telaprevir alone was well tolerated at 750 mg q8h for up to 12 weeks. The safety profile and emergence of resistant variants of genotype 1b under telaprevir monotherapy for 12 weeks will become increasingly important in evaluating an oral combination of telaprevir with other direct-acting antiviral agents.

Prevalence of herpes zoster virus reactivation in patients diagnosed with Bell's palsy.

OBJECTIVE: Herpes zoster virus can cause inflammatory neuropathy of the facial nerve. However, studies evaluating the prevalence of this agent in peripheral facial palsy are heterogeneous regarding sample group selection, laboratory analysis method and variables studied. In addition, there are a lack of epidemiological data in the Brazilian population on this serological phenomenon in peripheral facial palsy. This study estimated herpes zoster reactivation prevalence in serological samples through chemiluminescence immunoassay for quantitative determination of specific antibodies directed against the virus. METHODS: This cross-sectional study sought to determine the prevalence of viral reactivation by herpes zoster in subjects with idiopathic peripheral facial palsy through analysis of serological samples over a year. RESULTS: Forty-seven patients (32 females and 15 males) participated. Severe paralysis was more common in older patients (p = 0.017). Facial pain (p = 0.02) and vertigo (p = 0.001) were related to a worse evolution of facial palsy. The rate of serological reactivation of the virus was 12.76 per cent. CONCLUSION: The rate of serological reactivation of herpes virus in idiopathic peripheral facial palsy in our population is similar to foreign literature data, suggesting similar aetiological mechanisms in the genesis of this morbidity.

Changes in Fungicide Resistance Frequency and Population Structure of Pyricularia oryzae after Discontinuance of MBI-D Fungicides.

The changes in fungicide resistance frequency and population structure of the rice blast fungus Pyricularia oryzae were monitored after the discontinuance of melanin biosynthesis inhibitor targeting scytalone dehydratase (MBI-D) fungicides use in Saga Prefecture, Japan. After discontinuance in 2003, the frequency of resistant isolates decreased from 71.8% in 2002 to 25% in 2003, and became undetectable in 2007. The initial marked decrease was due to a decline of isolates possessing the predominant haplotype, although the haplotypic diversity among resistant isolates remained high from 2003 to 2005. These results revealed that resistant isolates were less fit in comparison with sensitive isolates in the absence of MBI-D fungicide pressure under field conditions. Pairwise FST values indicated that the change in population structure after MBI-D discontinuance was explainable by a rapid change in the proportions of resistant and sensitive subpopulations. Depending upon the existence of fitness cost and rapid changes in population structure, it may be possible to reintroduce MBI-D fungicides in areas where resistance has already developed, although we speculate that fitness cost related to MBI-D resistance may be small based on our present results and previous findings.

Occult hepatitis B virus infection increases hepatocellular carcinogenesis by eight times in patients with non-B, non-C liver cirrhosis: a cohort study.

An impact of serum hepatitis B virus (HBV) DNA on hepatocarcinogenesis has not been investigated in a cohort of patients with non-B, non-C cirrhosis. Eighty-two consecutive Japanese patients with cirrhosis, who showed negative hepatitis B surface antigen and negative anti-hepatitis C virus, were observed for a median of 5.8 years. Hepatitis B virus core (HBc) region and HBx region were assayed with nested polymerase chain reaction. Both of HBc and HBx DNA were positive in 9 patients (11.0%) and both were negative in 73. Carcinogenesis rates in the whole patients were 13.5% at the end of the 5th year and 24.6% at the 10th year. The carcinogenesis rates in the patients with positive DNA group and negative DNA group were 27.0% and 11.8% at the end of the 5th year, and 100% and 17.6% at the 10th year, respectively (P = 0.0078). Multivariate analysis showed that men (P = 0.04), presence of HBc and HBx DNA (hazard ratio: 8.25, P = 0.003), less total alcohol intake (P = 0.010), older age (P = 0.010), and association of diabetes (P = 0.005) were independently associated with hepatocellular carcinogenesis. Existence of serum HBV DNA predicted a high hepatocellular carcinogenesis rate in a cohort of patients with non-B, non-C cirrhosis.

Microtubules with 15 subunits in cockroach epidermal cells.

Since Ledbetter and Porter (1964) described the 13 subunits which are visible in cross sections of negatively stained plant microtubules, subsequent observations have generally confirmed this number. By using Mizuhira's fixative composed of tannic acid and glutaraldehyde, it is easyto demonstrate the subunits of microtublules without optical reinforcement Cytoplasmic microtubules and sperm axonemes, fixed with Mizuhira's fixtive, similarly show 13 subunits (Mizuhira's and Futaesaku, 1971, 1972; Futaesaky et al., 1972; Tilney et al., 1973). This paper will describe a particular type of microtubule in insect epidermal cells fixed with the above fixative. The number of the subunits is found to be 15 in tranverse sections.

Effect of vanadate on cartilage-matrix proteoglycan synthesis in rabbit costal chondrocyte cultures.

The effect of vanadate on proteoglycan synthesis by cultured rabbit costal chondrocytes was examined. Rabbit chondrocytes were seeded at low densities and grown to confluency in medium supplemented with 10% fetal bovine serum, and then the serum concentration was reduced to 0.3%. At the low serum concentration, chondrocytes adopted a fibroblastic morphology. Addition of 4 microM vanadate to the culture medium induced a morphologic differentiation of the fibroblastic cells to spherical chondrocytes, and increased by two- to threefold incorporation of [35S]sulfate and [3H]glucosamine into large, chondroitin sulfate proteoglycans. The stimulation of incorporation of labeled precursors reflected real increases in proteoglycan synthesis, in that chemical analyses showed increases in the accumulation of macromolecules containing hexuronic acid and hexosamine in vanadate-maintained cultures. However, vanadate had only a marginal effect on [35S]sulfate incorporation into small proteoglycans and [3H]glucosamine incorporation into hyaluronic acid and chondroitinase AC-resistant material. These results provide evidence that vanadate selectively stimulates the synthesis of proteoglycans characteristically found in cartilage by rabbit costal chondrocyte cultures.

Chondrogenic differentiation of clonal mouse embryonic cell line ATDC5 in vitro: differentiation-dependent gene expression of parathyroid hormone (PTH)/PTH-related peptide receptor.

The regulatory role of parathyroid hormone (PTH)/PTH-related peptide (PTHrP) signaling has been implicated in embryonic skeletal development. Here, we studied chondrogenic differentiation of the mouse embryonal carcinoma-derived clonal cell line ATDC5 as a model of chondrogenesis in the early stages of endochondral bone development. ATDC5 cells retain the properties of chondroprogenitor cells, and rapidly proliferate in the presence of 5% FBS. Insulin (10 micrograms/ml) induced chondrogenic differentiation of the cells in a postconfluent phase through a cellular condensation process, resulting in the formation of cartilage nodules, as evidenced by expression of type II collagen and aggrecan genes. We found that differentiated cultures of ATDC5 cells abundantly expressed the high affinity receptor for PTH (Mr approximately 80 kD; Kd = 3.9 nM; 3.2 x 10(5) sites/cell). The receptors on differentiated cells were functionally active, as evidenced by a PTH-dependent activation of adenylate cyclase. Specific binding of PTH to cells markedly increased with the formation of cartilage nodules, while undifferentiated cells failed to show specific binding of PTH. Northern blot analysis indicated that expression of the PTH/PTHrP receptor gene became detectable at the early stage of chondrogenesis of ATDC5 cells, preceding induction of aggrecan gene expression. Expression of the PTH/PTHrP receptor gene was undetectable in undifferentiated cells. The level of PTH/PTHrP receptor mRNA was markedly elevated parallel to that of type II collagen mRNA. These lines of evidence suggest that the expression of functional PTH/PTHrP receptor is associated with the onset of chondrogenesis. In addition, activation of the receptor by exogenous PTH or PTHrP significantly interfered with cellular condensation and the subsequent formation of cartilage nodules, suggesting a novel site of PTHrP action.

Sperm-egg recognition in the mouse: characterization of sp56, a sperm protein having specific affinity for ZP3.

Recognition between mammalian gametes occurs when the plasma membrane of the sperm head binds to the zona pellucida (ZP), an extracellular coat surrounding eggs. ZP3, one of three glycoproteins in the ZP, is the egg protein recognized by sperm. A mouse sperm surface protein, sp56 (M(r) = 56,000), has been identified on the basis of its specific affinity for ZP3 (Bleil, J. D., and P. M. Wassarman. 1990. Proc. Natl. Acad. Sci. USA. 87:5563-5567). Studies presented here were designed to characterize mouse sperm sp56 and to further test whether or not this protein specifically recognizes ZP3. sp56 was purified by both ZP3 affinity chromatography and by ion exchange chromatography followed by size-exclusion chromatography. The purified native protein eluted from size-exclusion columns as a homomultimer (M(r) approximately 110,000). Each monomer of the protein contains intramolecular disulfide bonds, consistent with its extracellular location. Immunohistochemical and immunoblotting studies, using monoclonal antibodies, demonstrated that sp56 is a peripheral membrane protein located on the outer surface of the sperm head plasma membrane, precisely where sperm bind ZP3. Results of crosslinking experiments demonstrated that the ZP3 oligosaccharide recognized by sperm has specific affinity for sp56. Collectively, these results suggest that sp56 may be the sperm protein responsible for sperm-egg recognition in the mouse.

Oxygen radicals in influenza-induced pathogenesis and treatment with pyran polymer-conjugated SOD.

The pathogenicity of influenza virus infection in the mice involves, at least in part, overreaction of the immune responses of the host rather than a direct effect of virus multiplication. Xanthine oxidase, which is responsible for the generation of oxygen free radicals, was elevated in serum and lung tissue of mice infected with influenza virus. To test the theory that oxygen-free radicals are involved in pathogenesis, free radicals were removed by injecting superoxide dismutase (SOD), a specific superoxide radical scavenger, which was conjugated with a pyran copolymer. The conjugate protected mice against a potentially lethal influenza virus infection if administered 5 to 8 days after infection. These findings indicate that oxygen radicals are important in the pathogenesis of influenza virus infection, and that a polymer-conjugated SOD has therapeutic potential for this virus infection and other diseases associated with free radicals.

Radiologic and Pathologic Features of the Transmantle Sign in Focal Cortical Dysplasia: The T1 Signal Is Useful for Differentiating Subtypes.

BACKGROUND AND PURPOSE: The transmantle sign is a characteristic MR imaging finding often seen in focal cortical dysplasia type IIb. The transmantle sign is typically hyperintense on T2WI and FLAIR and hypointense on T1WI. However, in some cases, it shows T1 high signal. We evaluated the imaging and pathologic findings to identify the causes of the T1 high signal in the transmantle sign. MATERIALS AND METHODS: We retrospectively reviewed the preoperative imaging data of 141 consecutive patients with histologically proved focal cortical dysplasia. We selected 25 patients with focal cortical dysplasia with the transmantle sign and divided them into groups based on the pathologic focal cortical dysplasia subtype and T1 signal of the transmantle sign. We evaluated the clinical, radiologic, and pathologic findings, including the number of balloon cells and dysmorphic neurons and the severity of gliosis or calcifications and compared them among the groups. RESULTS: Nine of the 25 patients had a T1-high-signal transmantle sign; the other 16 patients did not. All 9 patients with a T1-high-signal transmantle sign were diagnosed as type IIb (group A). Of the 16 patients with no T1-high-signal transmantle sign, 13 were diagnosed as having type IIb (group B), and the other 3 patients, as type IIa (group C). The number of balloon cells was significantly higher in group A than in the other groups, but there were no differences regarding dysmorphic neurons, the severity of gliosis, or calcifications. CONCLUSIONS: Approximately 6% (9/141) of this patient series had a T1-high-signal transmantle sign, and all were type IIb. The signal may reflect a rich density of balloon cells. This finding could support the differentiation of subtypes, especially type IIb.

Identification of the alpha1L-adrenoceptor in rat cerebral cortex and possible relationship between alpha1L- and alpha1A-adrenoceptors.

BACKGROUND AND PURPOSE: In addition to alpha1A, alpha1B and alpha1D-adrenoceptors (ARs), putative alpha1L-ARs with a low affinity for prazosin have been proposed. The purpose of the present study was to identify the alpha1A-AR and clarify its pharmacological profile using a radioligand binding assay. EXPERIMENTAL APPROACH: Binding experiments with [3H]-silodosin and [3H]-prazosin were performed in intact tissue segments and crude membrane preparations of rat cerebral cortex. Intact tissue binding assays were also conducted in rat tail artery. KEY RESULTS: [3H]-silodosin at subnanomolar concentrations specifically bound to intact tissue segments and membrane preparations of rat cerebral cortex at the same density (approximately 150 fmol mg(-1) total tissue protein). The binding sites in intact segments consisted of alpha1A and alpha1L-ARs that had different affinities for prazosin, while the binding sites in membranes showed an alpha1A-AR-like profile having single high affinity for prazosin. [3H]-prazosin also bound at subnanomolar concentrations to alpha1A and alpha1B-ARs but not alpha1L-ARs in cerebral cortex; the binding densities being approximately 200 and 290 fmol mg(-1) protein in the segments and the membranes, respectively. In the segments of tail artery, [3H]-silodosin only recognized alpha1A-ARs, whereas [3H]-prazosin bound to alpha1A and alpha1B-ARs. CONCLUSIONS AND IMPLICATIONS: The present study clearly reveals the presence of alpha1L-ARs as a pharmacologically distinct entity from alpha1A and alpha1B-ARs in intact tissue segments of rat cerebral cortex but not tail artery. However, the alpha1L-ARs disappeared after tissue homogenization, suggesting their decomposition and/or their pharmacological profile changes to that of alpha1A-ARs.

Evaluation of hydrogen absorption cells for observations of the planetary coronas.

Newly designed Lyman-alpha absorption cells for imaging hydrogen planetary corona were characterized using an ultra high resolution Fourier transform spectrometer installed on the DESIRS (Dichroïsme Et Spectroscopie par Interaction avec le Rayonnement Synchrotron) beamline of Synchrotron SOLEIL in France. The early absorption cell installed in the Japanese Mars orbiter NOZOMI launched in 1998 had not been sufficiently optimized due to its short development time. The new absorption cells are equipped with the ability to change various parameters, such as filament shape, applied power, H2 gas pressure, and geometrical configuration. We found that the optical thickness of the new absorption cell was ∼4 times higher than the earlier one at the center wavelength of Lyman-alpha absorption, by optimizing the condition to promote thermal dissociation of H2 molecules into two H atoms on a hot tungsten filament. The Doppler temperature of planetary coronas could be determined with an accuracy better than 100 K with the performance of the newly developed absorption cell.

Potent mitogenic effects of parathyroid hormone (PTH) on embryonic chick and rabbit chondrocytes. Differential effects of age on growth, proteoglycan, and cyclic AMP responses of chondrocytes to PTH.

The effect of PTH on chondrocyte proliferation as a function of cartilage age was examined. PTH[1-34] induced a 12- to 15-fold increase in the efficiency of colony formation in soft agar by chondrocytes from embryonic 13- to 19-d-old chickens and fetal 25-d-old rabbits with a 10-fold increase in their DNA content. It also caused a 2.5-fold increase in [3H]thymidine incorporation into DNA in fetal 25-d-old rabbit chondrocytes. No mitogenic responses to PTH were observed, however, in postnatal 7- to 21-d-old chick chondrocytes or postnatal 21-d-old rabbit chondrocytes. This age dependency was observed only with PTH: fibroblast growth factor, epidermal growth factor, and insulin stimulated chondrocyte proliferation irrespective of cartilage age. The absence of a mitogenic effect in postnatal chondrocytes was not due to a decrease in number or a reduction in affinity of receptors for PTH. PTH also increased [35S]sulfate incorporation into proteoglycans and the cyclic AMP level in fetal and postnatal chondrocytes, but at 100-fold higher concentrations (10(-8)-10(-7) M) than those (10(-10)-10(-9) M) required for the stimulation of cell division. These results suggest that PTH is a potent mitogen for embryonic chondrocytes, and that its mitogenic effect disappears selectively after birth.

Effects of interleukin-1 on syntheses of alkaline phosphatase, type X collagen, and 1,25-dihydroxyvitamin D3 receptor, and matrix calcification in rabbit chondrocyte cultures.

The effect of IL-1 on expression of the mineralization-related phenotype by chondrocytes was examined. In cultures of rabbit growth plate chondrocytes, IL-1 beta at 0.1 ng/ml caused 95% decreases in alkaline phosphatase activity, alkaline phosphatase mRNA levels, the incorporation of 45Ca into insoluble material, and the calcium content during the hypertrophic stage. These effects of IL-1 beta were dose-dependent and were observed in 24-48 h. Furthermore, IL-1 beta suppressed increase in cell size and the syntheses of 1,25-dihydroxyvitamin D3 receptor and type X collagen, other markers of hypertrophy, but had little effect on the synthesis of total protein including type II collagen. The inhibition of calcification was observed only when chondrocytes were exposed to IL-1 before the onset of calcification: IL-1 treatment from the mineralization stage had a marginal effect on 45Ca incorporation into insoluble material. These results suggest that IL-1 inhibits chondrocyte hypertrophy and the onset of calcification in ossifying cartilage.

High-performance affinity beads for identifying drug receptors.

We have developed a method using novel latex beads for rapid identification of drug receptors using affinity purification. Composed of a glycidylmethacrylate (GMA) and styrene copolymer core with a GMA polymer surface, the beads minimize nonspecific protein binding and maximize purification efficiency. We demonstrated their performance by efficiently purifying FK506-binding protein using FK506-conjugated beads, and found that the amount of material needed was significantly reduced compared with previous methods. Using the latex beads, we identified a redox-related factor, Ref-1, as a target protein of an anti-NF-kappaB drug, E3330, demonstrating the existence of a new class of receptors of anti-NF-kappaB drugs. Our results suggest that the latex beads could provide a tool for the identification and analysis of drug receptors and should therefore be useful in drug development.