Intra-abdominal desmoid fibromatosis mimicking tumour recurrence after the operation: A case series

INTRODUCTION

Desmoid fibromatosis is a multifactorial disorder classified as a category of intermediate, locally aggressive behaviour, which might be associated with CTNNB1 or APC mutations, trauma, surgery, or pregnancy.

CASE REPORTS

We present two cases of postoperative intra-abdominal desmoid fibromatosis. The first case occurred 14 months after the resection of a retroperitoneal gastrointestinal stromal tumour. The second case was located in the mesentery, as evidenced on an 18-month followup after a laparoscopy-assisted anterior resection for adenocarcinoma at the rectosigmoid junction. Under the clinical diagnosis of recurrence, tissue excisions were conducted. Microscopically, the tissue was composed of bland spindle cells without cytological atypia, admixed with collagen bundles. Both tumours exhibited nuclear expression of β-catenin on immunohistochemical staining, which is a desirable criterion for desmoid fibromatosis.

DISCUSSION

Although positron emission tomography aids the diagnosis of recurrence, the radiological features of desmoid fibromatosis in computed tomography or magnetic resonance images are nonspecific and preoperative diagnosis of desmoid fibromatosis is difficult. The histological diagnosis of desmoid fibromatosis is difficult, especially when the specimen is small. The histological differential diagnosis of desmoid fibromatosis includes other myofibroblastic or fibroblastic tumours or lesions. Additional studies, such as β-catenin immunohistochemistry or CTNNB1 mutation analysis, can enable accurate diagnosis of desmoid fibromatosis. A correct diagnosis is essential, because the current therapeutic strategy is a "waitand- watch" approach, which is significantly different from those of the other locally aggressive, intermediate soft tissue neoplasms. We have summarised the clinicopathological, histological and immunohistochemical features of the post-operative desmoid fibromatosis.

Ecological network analysis reveals distinctive microbial modules associated with heavy metal contamination of abandoned mine soils in Korea

Heavy metal pollution in soil around abandoned mine sites is one of the most critical environmental issues worldwide. Soil microbes form complex communities and perform ecological functions individually or in cooperation with other organisms to adapt to harsh environments. In this study, we investigated the distribution patterns of bacterial and fungal communities in non-contaminated and heavy metal-contaminated soil of the abandoned Samkwang mine in Korea to explore microbial interaction mechanisms and their modular structures. As expected, the bacterial and fungal community structures showed large differences depending on the degree of heavy metal contamination. The microbial network was divided into three modules based on the levels of heavy metal pollution: heavy metal-tolerant (HM-Tol), heavy metal-mid-tolerant (HM-mTol), and heavy metal-sensitive (HM-Sens) modules. Taxonomically, microbes assigned to Vicinamibacterales, Pedosphaeraceae, Nitrosomonadaceae, and Gemmatimonadales were the major groups constituting the HM-Tol module. Among the detected heavy metals (As, Pb, Cd, Cu, and Zn), copper concentrations played a key role in the formation of the HM-Tol module. In addition, filamentous fungi (Fusarium and Mortierella) showed potential interactions with bacteria (Nitrosomonadaceae) that could contribute to module stability in heavy metal-contaminated areas. Overall, heavy metal contamination was accompanied by distinct microbial communities, which could participate in the bioremediation of heavy metals. Analysis of the microbial interactions among bacteria and fungi in the presence of heavy metals could provide fundamental information for developing bioremediation mechanisms for the recovery of heavy metal-contaminated soil.

Compositional differences in hybrids between protoporphyrinogen IX oxidase (PPO)-inhibiting herbicide-resistant transgenic rice and weedy rice accessions

We characterized the metabolites in grains of transgenic protoporphyrinogen IX oxidase-inhibiting herbicide-resistant rice and weedy accessions using GC-MS and examined whether the chemical composition of their hybrids differed from that of the parents. We found that the metabolite profiles of transgenic rice and weedy rice were clearly separated. Although the metabolite profiles of F₂ progeny were partially separated from their parents, zygosity did not affect the profiles. The F₂ progeny had similar or intermediate levels of most major nutritional components compared with their parents. However, levels of galactopyranose, trehalose, xylofuranose, mannitol, and benzoic acid were higher in the F₂ progeny. Some fatty acids and organic acids also showed prominent quantitative differences between the F₂ progeny and the parents. Changes in the metabolite levels of transgenic crop-weed hybrids compared to their parents might influence not only the ecological consequences of the hybrids, but also the nutritional quality and food safety.

Performance of hybrids between abiotic stress-tolerant transgenic rice and its weedy relatives under water-stressed conditions

Gene transfer from transgenic crops to their weedy relatives may introduce undesired ecological consequences that can increase the fitness and invasiveness of weedy populations. Here, we examined the rate of gene flow from abiotic stress-tolerant transgenic rice that over-express AtCYP78A7, a gene encoding cytochrome P450 protein, to six weedy rice accessions and compared the phenotypic performance and drought tolerance of their hybrids over generations. The rate of transgene flow from AtCYP78A7-overexpressing transgenic to weedy rice varied between 0% and 0.0396%. F₁ hybrids containing AtCYP78A7 were significantly taller and heavier, but the percentage of ripened grains, grain numbers and weight per plant were significantly lower than their transgenic and weedy parents. The homozygous and hemizygous F₂ progeny showed higher tolerance to drought stress than the nullizygous F₂ progeny, as indicated by leaf rolling scores. Shoot growth of nullizygous F₃ progeny was significantly greater than weedy rice under water-deficient conditions in a rainout shelter, however, that of homozygous F₃ progeny was similar to weedy rice, indicating the cost of continuous expression of transgene. Our findings imply that gene flow from AtCYP78A7-overexpressing transgenic to weedy rice might increase drought tolerance as shown in the pot experiment, however, increased fitness under stressed conditions in the field were not observed for hybrid progeny containing transgenes.

Microscopic hematuria is a risk factor of incident chronic kidney disease in the Korean general population: a community-based prospective cohort study

BACKGROUND

Although asymptomatic microscopic hematuria (MH) is a common finding in clinical practice, its long-term outcome remains unknown.

AIM

This study evaluated the clinical implication of MH in the general population using a large-scale long-term longitudinal cohort database.

METHODS

This study included 8719 participants from the Korean Genome and Epidemiology Study between 2001 and 2014. MH was defined as ≥5 red blood cells per high-power field in random urinalysis without evidence of pyuria. The primary study outcome measure was incident chronic kidney disease (CKD), defined as estimated glomerular filtration rate <60 ml min-1⋅1.73⋅m-2.

RESULTS

During a median follow-up of 11.7 years, CKD occurred in 677 (7.8%) subjects. In Cox regression after adjustment for multiple confounders, subjects with MH had a significantly higher risk of incident CKD than those without [hazard ratio (HR) 1.45, 95% confidence interval (CI) 1.12-1.87; P = 0.005]. Isolated MH without proteinuria was also a risk factor of incident CKD (HR 1.37, 95% CI 1.04-1.79; P = 0.023) and the risk was further increased in MH with concomitant proteinuria (HR 5.41, 95% CI 2.54-11.49; P < 0.001). In propensity score matching analysis after excluding subjects with proteinuria, multi-variable stratified Cox regression analysis revealed that subjects with isolated MH had a significantly higher risk of incident CKD than those without (HR 1.83, 95% CI 1.14-2.94; P = 0.012).

CONCLUSION

The presence of MH is associated with an increased risk of incident CKD in the general population. Therefore, attentive follow-up is warranted in persons with MH for early detection of CKD.

Salinity affects metabolomic profiles of different trophic levels in a food chain

Salinization is one of the most important abiotic stressors in an ecosystem. To examine how exposing a host plant to excess salt affects the consequent performance and metabolism of insects in a food chain, we determined the life history traits and the metabolite profiles in rice (Oryza sativa), the herbivore Sitobion avenae, and its predator Harmonia axyridis. When compared with performance under normal (non-stressed) conditions, exposing plants to 50mM NaCl significantly delayed the timing of development for S. avenae fed on rice and H. axyridis and also reduced the body mass of the latter. Our GC-MS-based analysis revealed clear differences in metabolite profiles between trophic levels or treatment conditions. Salinity apparently increased the levels of main components in rice, but decreased levels of major components in S. avenae and H. axyridis. In addition, 16 metabolites showed salinity-related contrasts in this trophic interaction for our rice-S. avenae-H. axyridis system. Salinity impeded the accumulation of metabolites, especially several sugars, amino acids, organic acids, and fatty acids in both insects, a response that was possibly associated with the negative impacts on their growth and reproduction under stress conditions.

Comparative analysis of chemical compositions between non-transgenic soybean seeds and those from plants over-expressing AtJMT, the gene for jasmonic acid carboxyl methyltransferase

Transgenic overexpression of the Arabidopsis gene for jasmonic acid carboxyl methyltransferase (AtJMT) is involved in regulating jasmonate-related plant responses. To examine its role in the compositional profile of soybean (Glycine max), we compared the seeds from field-grown plants that over-express AtJMT with those of the non-transgenic, wild-type (WT) counterpart. Our analysis of chemical compositions included proximates, amino acids, fatty acids, isoflavones, and antinutrients. Overexpression of AtJMT in the seeds resulted in decreased amounts of tryptophan, palmitic acid, linolenic acid, and stachyose, but increased levels of gadoleic acid and genistein. In particular, seeds from the transgenic soybeans contained 120.0-130.5% more genistein and 60.5-82.1% less stachyose than the WT. A separate evaluation of ingredient values showed that all were within the reference ranges reported for commercially available soybeans, thereby demonstrating the substantial equivalence of these transgenic and non-transgenic seeds.

Metabolomic changes in grains of well-watered and drought-stressed transgenic rice

BACKGROUND

Drought induces a number of physiological and biochemical responses in cereals. This study was designed to examine the metabolite changes in grains of drought-tolerant transgenic rice (Oryza sativa L.) that overexpresses AtCYP78A7 encoding cytochrome P450 protein using proton nuclear magnetic resonance ((1)H-NMR) and gas chromatography/mass spectrometry.

RESULTS

Principal component analysis showed that the (1)H-NMR-based profile was clearly separated by soil water status of well-watered and water-deficit. A discrimination of metabolites between transgenic and non-transgenic grains appeared under both watering regimes. Variations in the levels of amino acids and sugars led to the discrimination of metabolites among genotypes. In particular, drought significantly enhanced the levels of γ-aminobutyric acid (GABA, 244.6%), fructose (155.7%), glucose (211.0%), glycerol (57.2%), glycine (65.8%) and aminoethanol (192.4%) in the transgenic grains compared with the non-transgenic control grains.

CONCLUSION

These changes in amounts of metabolites may assist in improving drought tolerance in transgenic rice by playing crucial roles in stress-responsive pathways including GABA biosynthesis, sucrose metabolism and antioxidant defenses.

Drought stress-induced compositional changes in tolerant transgenic rice and its wild type

Comparing well-watered versus deficit conditions, we evaluated the chemical composition of grains harvested from wild-type (WT) and drought-tolerant, transgenic rice (Oryza sativa L.). The latter had been developed by inserting AtCYP78A7, which encodes a cytochrome P450 protein. Two transgenic Lines, '10B-5' and '18A-4', and the 'Hwayoung' WT were grown under a rainout shelter. After the harvested grains were polished, their levels of key components, including proximates, amino acids, fatty acids, minerals and vitamins were analysed to determine the effect of watering system and genotype. Drought treatment significantly influenced the levels of some nutritional components in both transgenic and WT grains. In particular, the amounts of lignoceric acid and copper in the WT decreased by 12.6% and 39.5%, respectively, by drought stress, whereas those of copper and potassium in the transgenics rose by 88.1-113.3% and 10.4-11.9%, respectively, under water-deficit conditions.

Interactions among LOX metabolites regulate temperature-mediated flower bud formation in morning glory (Pharbitis nil)

We examined the relationship between temperature (15-35°C) and flower induction as it is influenced by linolenic acid (LA) cascade products, lipoxygenase (LOX; EC 1.13.11.12), allene oxide synthase (AOS; EC 4.2.1.92), and allene oxide cyclase (AOC; EC 5.3.99.6) generated in morning glory (Pharbitis nil Choisy). The maximum amount of LOX protein was detected when plants were grown at 30°C, whereas endogenous AOS and AOC proteins were markedly accumulated at 15°C. Although both test levels of 9(S)- and 13(S)-hydroperoxy linolenic acid (HPOT) showed similar temperature dependencies, reflecting the profile of LOX, the relative amount of 13(S)-HPOT was much higher than that of 9(S)-HPOT, regardless of temperature regime. This implied a faster reaction pathway to 9,10-α-ketol octadecadienoic acid (KODA) in the LA cascade. In the 13(S)-HPOT pathway, the highest level of endogenous jasmonic acid (JA) was observed at 15°C. Our results suggest that at a high temperature (30°C), 9(S)-HPOT may be readily metabolized into KODA to promote flower bud formation. By contrast, at a low temperature, high levels of AOS and AOC result in an accumulation of JA that inhibits this developmental process. Accordingly, depending on the growing temperature, flower bud formation in P. nil is possibly regulated by the interactions among LOX metabolites, with KODA serving as a promoter and JA as an inhibitor.

Laser-driven proton acceleration enhancement by nanostructured foils

Nanostructured thin plastic foils have been used to enhance the mechanism of laser-driven proton beam acceleration. In particular, the presence of a monolayer of polystyrene nanospheres on the target front side has drastically enhanced the absorption of the incident 100 TW laser beam, leading to a consequent increase in the maximum proton energy and beam charge. The cutoff energy increased by about 60% for the optimal spheres' diameter of 535 nm in comparison to the planar foil. The total number of protons with energies higher than 1 MeV was increased approximately 5 times. To our knowledge this is the first experimental demonstration of such advanced target geometry. Experimental results are interpreted and discussed by means of 2(1/2)-dimensional particle-in-cell simulations.

Absolute energy calibration for relativistic electron beams with pointing instability from a laser-plasma accelerator

The pointing instability of energetic electron beams generated from a laser-driven accelerator can cause a serious error in measuring the electron spectrum with a magnetic spectrometer. In order to determine a correct electron spectrum, the pointing angle of an electron beam incident on the spectrometer should be exactly defined. Here, we present a method for absolutely calibrating the electron spectrum by monitoring the pointing angle using a scintillating screen installed in front of a permanent dipole magnet. The ambiguous electron energy due to the pointing instability is corrected by the numerical and analytical calculations based on the relativistic equation of electron motion. It is also possible to estimate the energy spread of the electron beam and determine the energy resolution of the spectrometer using the beam divergence angle that is simultaneously measured on the screen. The calibration method with direct measurement of the spatial profile of an incident electron beam has a simple experimental layout and presents the full range of spatial and spectral information of the electron beams with energies of multi-hundred MeV level, despite the limited energy resolution of the simple electron spectrometer.

P2-16-15: Oncological Safety and Survival Rate According to Reconstructive Surgery in Advanced Breast Cancer after Neoadjuvant Chemotherapy

Purpose: Oncoplastic surgery has received attention according as the incidence of breast cancer is rising and quality of life including cosmetic result after surgery is regarded as important. The aim of this study is to compare combined reconstructive surgery with standard surgery regarding to oncological safety and survival rate in advanced breast cancer after neoadjuvant chemotherapy (CTx).

Method: Thirty-seven patients underwent neoadjuvant CTx and surgery with advanced breast cancer were analyzed from September 2007 to March 2010. Group A (n=12) received combined reconstructive surgery, group B (n=25) had standard surgery.

Results: There were no differences in age, size, metastatic LN, stage, ER/PR/Her-2 status, recurrence, metastasis and death between group A and B. Patients with good response in neoadjuvant chemotherapy (26 cases (72.9%)) had CTx-operation-radiation therapy (RTx), cases with poor response (10 cases (27.1%)) underwent CTx-RTx-operation. There was significant difference in order of treatment, eight patients among group A(66.6%) had CTx-RTx-operation, 22 cases in group B(88.0%) received CTx-operation-RTx (p=0.006). Mean follow up period was 22 months, 2 patients (5.2%) experienced local recurrences, 11 cases (34.3%) diagnosed with distant metastasis, and 4 patients (10.5%) expired with breast cancer.

Novel dentin phosphoprotein frameshift mutations in dentinogenesis imperfecta type II

The dentin sialophosphoprotein (DSPP) gene encodes the most abundant non-collagenous protein in tooth dentin and DSPP protein is cleaved into several segments including the highly phosphorylated dentin phosphoprotein (DPP). Mutations in the DSPP gene have been solely related to non-syndromic form of hereditary dentin defects. We recruited three Korean families with dentinogenesis imperfecta (DGI) type II and sequenced the exons and exon-intron boundaries of the DSPP gene based on the candidate gene approach. Direct sequencing of PCR products and allele-specific cloning of the highly repetitive exon 5 revealed novel single base pair (bp) deletional mutations (c.2688delT and c.3560delG) introducing hydrophobic amino acids in the hydrophilic repeat domain of the DPP coding region. All affected members of the three families showed exceptionally rapid pulp chambers obliteration, even before tooth eruption. Individuals with the c.3560delG mutation showed only mild, yellowish tooth discoloration, in contrast to the affected individuals from two families with c.2688delT mutation. We believe that these results will help us to understand the molecular pathogenesis of DGI type II as well as the normal process of dentin biomineralization.

Novel WDR72 mutation and cytoplasmic localization

The proven candidate genes for amelogenesis imperfecta (AI) are AMELX, ENAM, MMP20, KLK4, FAM83H, and WDR72. We performed mutation analyses on seven families with hypomaturation AI. A novel WDR72 dinucleotide deletion mutation (g.57,426_57,427delAT; c.1467_ 1468delAT; p.V491fsX497) was identified in both alleles of probands from Mexico and Turkey. Haplotype analyses showed that the mutations arose independently in the two families. The disease perfectly segregated with the genotype. Only persons with both copies of the mutant allele were affected. Their hypomineralized enamel suffered attrition and orange-brown staining following eruption. Expression of WDR72 fused to green fluorescent protein showed a cytoplasmic localization exclusively and was absent from the nucleus. We conclude that WDR72 is a cytoplasmic protein that is critical for dental enamel formation.

Incidence and clinical behavior of papillary thyroid carcinoma in renal allograft recipients: a single center experience

The chronic use of immunosuppressive therapy in transplant recipients increases the long-term risk for carcinoma. However, there is insufficient knowledge regarding the incidence and biological behavior of papillary thyroid carcinomas (PTC) in renal allograft recipients. In the present study we examined the incidence and biological behavior of PTCs among 1739 patients transplanted between January 1986 and December 1999 who had been followed for a mean period of 137 months (range, 84-238 months). During the follow-up, 129 (7.4%) recipients were identified to display posttransplantation malignancies, including 12 (0.7%) with PTCs. The 6 male and 6 female patients had a mean age of 41 years (range, 23-57 years). Nine cases (incidentalomas) were diagnosed based on ultrasonographic (US) screening. Eight of those 9 were TNM stage I, 2 of the 3 clinical carcinomas were TNM stage IVa. During a mean follow-up of 94 months (range, 18-159 months), 2 (16.7%) PTC patients developed locoregional recurrence, but no patients showed distant metastases. These data showed that recipients had a higher incidence of PTC compared with the general Korean population (0.7% vs 0.02%). Posttransplantation PTC tended to show no difference in gender distribution, and was often associated with aggressive lymphatic metastasis. However, most incidentalomas showed favorable treatment outcomes. In conclusion, routine surveillance of the thyroid gland using US screening is recommended to ensure early detection, treatment, and favorable prognosis of PTC.

Temperature regulates tuber-inducing lipoxygenase-derived metabolites in potato (Solanum tuberosum)

Temperature is one of the major environmental factors affecting potato tuberization. It has been suggested that lipoxygenase (LOX) mediates between temperature and tuber induction. In this study, the contents of the LOX-derived metabolites hydroperoxylinolenic acid (HPOT), jasmonic acid (JA), tuberonic acid (TA) and tuberonic acid glucoside (TAG) were analyzed in leaves of potatoes growing at different temperatures. At low, tuber-inducing temperature, endogenous levels of JA, TA and TAG rise, indicating their crucial role in tuber induction. The concentration of 13(S)-HPOT seems not to be directly affected by temperature. Instead, the molecule has only a short half-life in leaves and is readily metabolized.

Inhibition of stem elongation in spinach by theobroxide

In the current study, we investigated the influences of theobroxide on stem elongation in spinach (Spinacia oleracea). Our results showed that stem elongation and flower formation were inhibited by spraying spinach plants with theobroxide under inductive, long day conditions (16 h light/8 h dark), while application of exogenous applied GA3 prevented the effect of theobroxide. Quantitative analysis showed that theobroxide suppressed GA1 biosynthesis, whereas the endogenous content of jasmonic acid was unchanged. However, under short day conditions (10 h light/14 h dark), there were no differences in stem length between treated and untreated plants. These results suggest that the inhibition of stem elongation by theobroxide is probably due to the suppression of gibberellin biosynthesis.

Anti-cancer effect of adenovirus p53 on human cervical cancer cell growth in vitro and in vivo

To evaluate anti-tumor effects of recombinant adenovirus p53, time-course p53, E6 expression, and cell growth inhibition were investigated in vitro and in vivo using cervical cancer cell lines such as CaSki, SiHa, HeLa, HeLaS3, C33A, and HT3. The cell growth inhibition was studied via cell count assay, MTT assay and neutral red assay. After transfecting AdCMVp53 into SiHa cells-xenografted nude mice, the transduction efficiency and anti-tumor effect were investigated for a month. The results showed that adenoviral p53 expression induced significant growth suppression on the cancer cells, in which E6 transcript was strongly repressed, and that the expression of p53 and E6 were remarkably dependent on each cell type. The transduction efficiency was highly maintained in vivo as well as in vitro, and the size of tumor was remarkably decreased in comparison with AdCMVLacZ control. The results suggest that the adenovirus-mediated p53 gene transfection was done very effectively in vitro and in vivo experiment, and the cell growth was suppressed via p53-dependent apoptotic cell death, and that the anti-tumor effect could be related to E6 and p53 expression pattern.

Synthesis and antibacterial activity of new 1beta-methylcarbapenems having the potential for intramolecular nonbonded S...O interactions

Mercaptoacetyliminothiadiazoline derivatives (19, 20) useful for the pendant moiety of 1beta-methylcarbapenem antibiotics were efficiently synthesized. Acetyl derivative (18) of 20 was submitted to X-ray analysis, and a significant nonbonded S...O close contact was recognized in the crystallographic structure. New 1beta-methylcarbapenems (5, 6) were synthesized by exploiting 19 and 20, and exhibited considerable antibacterial activities in vitro.

Enhanced levels of the aroma and flavor compound S-linalool by metabolic engineering of the terpenoid pathway in tomato fruits

The aromas of fruits, vegetables, and flowers are mixtures of volatile metabolites, often present in parts per billion levels or less. We show here that tomato (Lycopersicon esculentum Mill.) plants transgenic for a heterologous Clarkia breweri S-linalool synthase (LIS) gene, under the control of the tomato late-ripening-specific E8 promoter, synthesize and accumulate S-linalool and 8-hydroxylinalool in ripening fruits. Apart from the difference in volatiles, no other phenotypic alterations were noted, including the levels of other terpenoids such as gamma- and alpha-tocopherols, lycopene, beta-carotene, and lutein. Our studies indicate that it is possible to enhance the levels of monoterpenes in ripening fruits by metabolic engineering.

BIN2, a new brassinosteroid-insensitive locus in Arabidopsis

Brassinosteroids (BRs) play important roles throughout plant development. Although many genes have been identified that are involved in BR biosynthesis, genetic approaches in Arabidopsis have led to the identification of only one gene, BRI1, that encodes a membrane receptor for BRs. To expand our knowledge of the molecular mechanism(s) of plant steroid signaling, we analyzed many dwarf and semidwarf mutants collected from our previous genetic screens and identified a semidwarf mutant that showed little response to exogenous BR treatments. Genetic analysis of the bin2 (BR-INSENSITIVE 2) mutant indicated that the BR-insensitive dwarf phenotype was due to a semidominant mutation in the BIN2 gene that mapped to the middle of chromosome IV between the markers CH42 and AG. A direct screening for similar semidwarf mutants resulted in the identification of a second allele of the BIN2 gene. Despite some novel phenotypes observed with the bin2/+ mutants, the homozygous bin2 mutants were almost identical to the well-characterized bri1 mutants that are defective in BR perception. In addition to the BR-insensitive dwarf phenotype, bin2 mutants exhibited BR insensitivity when assayed for root growth inhibition and feedback inhibition of CPD gene expression. Furthermore, bin2 mutants displayed an abscisic acid-hypersensitive phenotype that is shared by the bri1 and BR-deficient mutants. A gene dosage experiment using triploid plants suggested that the bin2 phenotypes were likely caused by either neomorphic or hypermorphic gain-of-function mutations in the BIN2 gene. Thus, the two bin2 mutations define a novel genetic locus whose gene product might play a role in BR signaling.

In-vitro and in-vivo immunomodulatory effects of syringin

Syringin was found to possess immunomodulatory activity by which it inhibited the in-vitro immunohaemolysis of antibody-coated sheep erythrocytes by guinea-pig serum through suppression of C3-convertase of the classical complement. In this study, we examined its in-vitro and in-vivo activity on tumour necrosis factor (TNF)-alpha and nitric oxide (NO) production, CD4+ T cell and CD8+ cytotoxic T cell (CTLL-2) proliferation, and croton oil-, arachidonic acid- and fluorescein-isothiocynate (FITC)-induced mouse ear oedema model. Syringin significantly inhibited both TNF-alpha production from lipopolysaccharide (LPS)-stimulated RAW264.7 cells and CD8+ T cell (CTLL-2) proliferation in a dose-dependent manner, whereas neither NO production nor CD4+ T cell proliferation were blocked even by high concentrations of syringin. In the invivo experiments, syringin also significantly suppressed FITC-induced ear oedema in mice but not the ear oedema induced by croton or arachidonic acid. These results suggest that syringin may be implicated as an immunomodulator having an anti-allergic effect rather than an anti-inflammatory effect. The anti-allergic effect of syringin seems to be due, in part, to inhibition of TNF-alpha production and cytotoxic T cell proliferation.

CD3 polymorphism in cynomolgus monkeys (Macaca fascicularis)

Cynomolgus monkeys were divided into two groups in terms of the reactivity of their lymphocytes with the FN18 monoclonal antibody, which is directed to the CD3 of rhesus monkeys. It was shown that 24 (12.2%) out of 196 monkeys did not have lymphocytes that reacted with the FN18, although T cells from those animals responded well to mitogenic stimulation. We have determined the nucleotide sequences of the CD3delta, CD3gamma, and CD3epsilon chains and found that two amino acids of the CD3epsilon chain of the FN18 non-reactive monkeys were different when compared with the FN18 reactive monkeys. Our results indicated that the CD3epsilon molecule of cynomolgus monkeys is polymorphic at the epitope level, which is recognized by the FN18 monoclonal antibody.

Transglutaminase-mediated crosslinking of specific core histone subunits and cellular senescence

We observed that the transglutaminase (tTGase) level and activity increased in aged rats and senescent primary fibroblasts, suggesting that the tTGase-mediated macromolecule crosslinking may play a mechanistic role during aging. Although preliminary, our in vitro experiment suggests that the target of tTGase is core histones: H2A:H2B and H3:H4 are specifically crosslinked by tTGase. On the basis of these data, we postulate that the changes of DNA metabolism in association with cellular aging may be ascribed primarily to the crosslinking of core histone subunits. Further speculation awaits substantive data showing increased histone crosslinking in senescent cells and also what crosslinked histones in various DNA metabolisms may imply. At the moment, present data are sufficient to propose that tTGase is a senescence marker and it may be primarily responsible for the phenotypes associated with cellular senescence.

An investigation of the storage and biosynthesis of phenylpropenes in sweet basil

Plants that contain high concentrations of the defense compounds of the phenylpropene class (eugenol, chavicol, and their derivatives) have been recognized since antiquity as important spices for human consumption (e.g. cloves) and have high economic value. Our understanding of the biosynthetic pathway that produces these compounds in the plant, however, has remained incomplete. Several lines of basil (Ocimum basilicum) produce volatile oils that contain essentially only one or two specific phenylpropene compounds. Like other members of the Lamiaceae, basil leaves possess on their surface two types of glandular trichomes, termed peltate and capitate glands. We demonstrate here that the volatile oil constituents eugenol and methylchavicol accumulate, respectively, in the peltate glands of basil lines SW (which produces essentially only eugenol) and EMX-1 (which produces essentially only methylchavicol). Assays for putative enzymes in the biosynthetic pathway leading to these phenylpropenes localized many of the corresponding enzyme activities almost exclusively to the peltate glands in leaves actively producing volatile oil. An analysis of an expressed sequence tag database from leaf peltate glands revealed that known genes for the phenylpropanoid pathway are expressed at very high levels in these structures, accounting for 13% of the total expressed sequence tags. An additional 14% of cDNAs encoded enzymes for the biosynthesis of S-adenosyl-methionine, an important substrate in the synthesis of many phenylpropenes. Thus, the peltate glands of basil appear to be highly specialized structures for the synthesis and storage of phenylpropenes, and serve as an excellent model system to study phenylpropene biosynthesis.

Experimental autoimmune encephalomyelitis in cynomolgus monkeys

Experimental autoimmune encephalomyelitis was induced in macaques. T cell clones infiltrated into the brain lesion area were compared with those in blood. Intradermal immunization of macaques with brain white matter derived from healthy macaque in combination with pertussis toxin, induced neurological symptoms in two macaques. One died on day 25 after immunization, whereas the other survived. Gross examination of the brain from the dead macaque, showed clear hemorrhagic lesions in the white matter. Hematological analysis showed that drastic T cell response was induced in macaques immunized with white matter, but not in control macaques. Flow cytometric analysis of blood cells from the affected macaques demonstrated an increase of CD4 and CD8 T cell populations expressing the CD69 early activation marker. Single strand conformation polymorphism (SSCP) analysis of T cell receptor beta chain showed T cell clones infiltrated into the brain lesion, which were different from those found in the peripheral blood of the same monkey. The present paper shows that SSCP analysis of TCR is useful in studying clonality of T cells infiltrating into the brain tissue of macaque with EAE.

Characterization of expanded T cell clones in healthy macaques: ontogeny, distribution and stability

Peripheral expanded T cell clones have been discussed mainly in relation to certain diseases or immune function in humans and mice. There is little information on their ontogeny, stability and distribution among T cell subsets as well as major lymphoid organs. We applied reverse transcription-polymerase chain reaction (RT-PCR) with family specific primers for monkey T cell receptor beta chain V regions and single-strand conformation polymorphism (SSCP) analysis to analyze the expanded T cell clones in cynomolgus monkeys (Macaca fascicularis). A number of expanded T cell clones were detected in the peripheral blood of young and adult monkeys, but few expanded T cell clones were detected in the blood of a fetus and a 2-day-old neonate. The clones in adults were maintained over 3 months. These expanded T cell clones were distributed only in peripheral blood and spleen, but few were found in lymph nodes (axillary, inguinal and intestinal). The number of expanded T cell clones was much greater in CD8 single-positive (CD8sp) T cells than in CD4sp T cells, showing that most of these clones originated in the CD8sp T cell population. Almost all the expanded CD8sp T cell clones belonged to the CD28(-), CD29(hi) and Fas(+) subset. The usage of V beta genes was not skewed in the 24 V beta. Furthermore, higher mRNA signals for effector molecules perforin and IFN-gamma were detected in CD8sp T cell subsets with phenotypes of CD28(-), CD29(hi) and Fas(+), suggesting that the expanded T cells might have developed in relation to T cell activation in the periphery of cynomolgus monkeys.

Auxin and brassinosteroid differentially regulate the expression of three members of the 1-aminocyclopropane-1-carboxylate synthase gene family in mung bean (Vigna radiata L.)

Indole-3-acetic acid (IAA) markedly increased ethylene production by inducing the expression of three 1aminocyclopropane-1-carboxylate (ACC) synthase cDNAs (pVR-ACS1, pVR-ACS6 and pVR-ACS7) in mung bean hypocotyls. Results from nuclear run-on transcription assay and RNA gel blot studies revealed that all three genes were transcriptionally active displaying unique patterns of induction by IAA and various hormones in etiolated hypocotyls. Particularly, 24-epibrassinolide (BR), an active brassinosteroid, specifically enhanced the expression of VR-ACS7 by a distinct temporal induction mechanism compared to that of IAA. In addition, BR synergistically increased the IAA-induced VR-ACS6 and VR-ACS7 transcript levels, while it effectively abolished both the IAA- and kinetin-induced accumulation of VR-ACS1 mRNA. In light-grown plants, VR-ACS1 was induced by IAA in roots, and VR-ACS6 in epicotyls. IAA- and BR-treatments were not able to increase the VR-ACS7 transcript in the light-grown tissues. These results indicate that the expression of ACC synthase multigene family is regulated by complex hormonal and developmental networks in a gene- and tissue-specific manner in mung bean plants. The VR-ACS7 gene was isolated, and chimeric fusion between the 2.4 kb 5'-upstream region and the beta-glucuronidase (GUS) reporter gene was constructed and introduced into Nicotiana tabacum. Analysis of transgenic tobacco plants revealed the VR-ACS7 promoter-driven GUS activity at a highly localized region of the hypocotyl-root junction of control seedlings, while a marked induction of GUS activity was detected only in the hypocotyl region of the IAA-treated transgenic seedlings where rapid cell elongation occurs. Although there was a modest synergistic effect of BR on the IAA-induced GUS activity, BR alone failed to increase the GUS activity, suggesting that induction of VR-ACS7 occurs via separate signaling pathways in response to IAA and BR. A scheme of the multiple regulatory pathways for the expression of ACC synthase multigene family by auxin and BR is presented.

Characterization of benzylalcohol acetyltransferases in scented and non-scented Clarkia species

The floral scent of Clarkia breweri, an annual native to California, contains copious amounts of benzylacetate, which is synthesized by a reaction of benzylalcohol and acetyl-CoA that is catalyzed by acetyl-CoA:benzylalcohol acetyltransferase (BEAT). Here we demonstrate that different lines of C. breweri contain different levels of BEAT activity even though they have similar levels of BEAT mRNA. We also present evidence that the genome of C. breweri's non-scented progenitor, C. concinna, contains BEAT genes, but that its flowers have little BEAT enzymatic activity. This is due to the fact that although C. concinna BEAT genes are transcribed in the flowers, the single intron in these transcripts is almost never spliced out, and when the intron is spliced out, the resulting enzyme has higher affinity with substrates other than benzylalcohol. These results indicate that the regulation of BEAT activity in Clarkia involves post-transcriptional mechanisms.

S-Adenosyl-L-methionine:salicylic acid carboxyl methyltransferase, an enzyme involved in floral scent production and plant defense, represents a new class of plant methyltransferases

S-Adenosyl-L-methionine:salicylic acid carboxyl methyltransferase (SAMT) was partially purified from petals of the annual California plant Clarkia breweri. SAMT catalyzes the formation of methylsalicylate, an important floral scent compound in C. breweri, from salicylic acid and S-adenosyl-L-methionine (SAM). The native enzyme is a dimer with a subunit molecular weight of 40.3 kDa, and it has a Km for salicylic acid of 24 microM and a Km for SAM of 9 microM. A cDNA encoding SAMT was isolated from a C. breweri cDNA library prepared from floral mRNA. The sequence of the protein encoded by SAMT cDNA shows no significant sequence similarity to any protein in the data bank whose biochemical function is known. It does show significant sequence similarity (20-40% identity) to proteins encoded by at least seven Arabidopsis thaliana genes whose sequences have recently been determined in large-scale sequencing projects. The C. breweri SAMT cDNA was expressed in E. coli and the bacterial cells synthesized a functional SAMT protein with properties nearly identical to those of the plant-purified enzyme.

Effects of SIVmac infection on peripheral blood CD4+CD8+ T lymphocytes in cynomolgus macaques

We have previously reported that CD4+CD8+ double-positive (DP) T cells with a resting memory phenotype exist in a substantial proportion of peripheral blood lymphocytes of adult cynomolgus macaques. In this study, we examined the effects of simian immunodeficiency virus of macaque (SIVmac) infection on DP T cells. In vitro, SIVmac239 nef-open (239) and its nef-deletion mutant replicated well in both CD4+CD8- and DP T cells. However, when the macaques were infected with 239, DP, but not CD4+CD8-, T cells were transiently increased in parallel with cell activation and viral replication, followed by depletion within 1 month postinfection. Interestingly, the nef gene was required for depletion but not for the increase and activation of DP T cells. These data suggest that the pathogenic SIV infection may downmodulate production and/or blood circulation of DP T cells by a Nef function-related mechanism(s) different from that for the depletion of CD4+CD8- T cells.

Synthesis and antibacterial activity of 1 beta-methylcarbapenem having a 1,3-diazabicyclo[3.3.0]octan-4-one moiety, Part II

The synthesis of a new series of 1 beta-methylcarbapenems having a 1,3-diazabicyclo[3.3.0]octan-4-one moiety is described. Their in vitro antibacterial activities against both Gram-positive and Gram-negative bacteria are tested and the effect of substituent on the bicyclic ring was investigated. A particular compound (11 h) having aminoethyl group showed the most potent antibacterial activity.

The formation of adjacent triplex-duplex domainsin DNA

The ability of single-stranded DNA oligomers to form adjacent triplex and duplex domains with two DNA structural motifs was examined. Helix-coil transition curves and a gel mobility shift assay were used to characterize the interaction of single-stranded oligomers 12-20 nt in length with a DNA hairpin and with a DNA duplex that has a dangling end. The 12 nt on the 5'-ends of the oligomers could form a triplex structure with the 12 bp stem of the hairpin or the duplex portion of the DNA with a dangling end. The 3'-ends of the 17-20 nt strands could form Watson-Crick pairs to the five base loop of the hairpin or the dangling end of the duplex. Complexes of the hairpin DNA with the single-stranded oligomers showed two step transitions consistent with unwinding of the triplex strand followed by hairpin denaturation. Melting curve and gel competition results indicated that the complex of the hairpin and the 12 nt oligomer was more stable than the complexes involving the extended single strands. In contrast, results indicated that the extended single-stranded oligomers formed Watson-Crick base pairs with the dangling end of the duplex DNA and enhanced the stability of the adjacent triplex region.

Phenotypic changes in peripheral blood monocytes of cynomolgus monkeys acutely infected with simian immunodeficiency virus

The quantitative and phenotypic changes of peripheral blood monocytes during the acute stage of simian immunodeficiency virus infection were investigated. We inoculated intravenously three cynomolgus monkeys (Macaca fascicularis) with 100 TCID50 of SIVmac239 and collected whole blood twice a week until 35 days postinoculation. We found that the relative number of monocytes in peripheral blood leukocytes significantly increased at 7-17 days postinoculation. This increase was concomitant with the peak of primary SIV antigenemia. To determine if the monocytes observed during the acute stage were phenotypically altered, they were periodically examined for the expression of surface markers (i.e., CD11b, CD14, CD16, CD29, D32, CD56, CD62L, CD64, CD80, and MHC-II-DR) by flow cytometry. The results showed that the expression levels of CD14 and CD56 on most of the monocytes were remarkably reduced at 7-17 days postinoculation, and a new subpopulation, CD14lowCD16+CD80+ monocytes, was clearly detected at 10 days postinoculation. These results indicate that the phenotypic alteration of peripheral blood monocytes occurs during the primary SIV infection.

Age-related changes in major lymphocyte subsets in cynomolgus monkeys

Age-related changes in major lymphocyte subsets were analyzed in 195 cynomolgus monkeys (Macaca fascicularis) aged from one month to 31 years. The percentages of CD20+ B cells in peripheral blood lymphocytes (PBL) decreased with age to five years of age, but after that, no significant change was observed. The percentages of CD16+ NK cells gradually increased during the first five years and reached the peak at from four to ten years of age, whereas the percentages of CD3+ T cells in PBL were relatively constant throughout the life. Among the T cells, the CD4+ CD8- T cells decreased, but CD4- CD8+ T cells increased within the first decade of life. We further analyzed the expressions of CD28 and CD29 molecules on T cells to determine the relation between age-related activation and phenotypic changes. Almost all CD4+ CD8- T cells (> 90%) were CD28+ at all ages analyzed, but a clear age-related decrease in CD28 expression was demonstrated in CD4- CD8+ T cells during the first ten years. In the case of CD29 expression, age-related increases in CD29hi cells were apparent in both CD4+ CD8- and CD4- CD8+ T cells during the first ten years. The percentages of CD29hi cells, however, were higher in CD4- CD8+ T cells than in CD4+ CD8- T cells in all ages analyzed. These results indicated that the age-related changes in percentages of major lymphocyte subsets as well as in phenotypes of T cells might be related to the maturation of the immune system including an increase in memory cells in cynomolgus monkeys.

Acetyl-CoA:benzylalcohol acetyltransferase--an enzyme involved in floral scent production in Clarkia breweri

Volatile esters impart distinct characteristics to the floral scent of many plants, and are important in attracting insect pollinators. They are also important flavor compounds in fruits. The ester benzylacetate is a major constituent of the floral scent of Clarkia breweri, an annual plant native to California. The enzyme acetyl-CoA:benzylalcohol acetyltransferase (BEAT), which catalyzes the formation of benzylacetate, has been purified from C. breweri petals, and a cDNA encoding this enzyme has been isolated and characterized. The sequence of the 433-residue BEAT protein does not show high similarity to any previously characterized protein, but a 35-residue region from position 135-163 has significant similarity (42-56% identity) to several proteins known or suspected to use an acyl-CoA substrate. E. coli cells expressing C. breweri BEAT produced enzymatically active protein, and also synthesized benzylacetate and secreted it into the medium. Of the different parts of the C. breweri flower, petals contained the majority of BEAT transcripts, and no BEAT mRNA was detected in leaves. The levels of BEAT mRNA in the petals increased as the bud matured, and peaked at anthesis, paralleling changes in BEAT activity. However, three days after anthesis, mRNA levels began a steep decline, whereas BEAT activity remained high for the next two days, suggesting that the BEAT protein is relatively stable.

Age-dependent remodeling of peripheral blood CD4+ CD8+ T lymphocytes in cynomolgus monkeys

Recently, we have found in adult cynomolgus monkeys that substantial peripheral blood CD4+ CD8+ double-positive (DP) T lymphocytes exhibit a resting memory phenotype and increase in proportion with age. In this study, we investigated whether phenotypic changes occur in the course of the increase in proportion of the DP T cells. The results obtained from 195 clinically healthy monkeys aged from 1 month to 31 years showed that the CD29hi and CD28 subpopulation in the DP T subset increased in proportion with age and that the increase reached a plateau at six years old for the CD29hi subpopulation and at eleven years old for the CD28 one, respectively. The phenotypic alteration preceded the abrupt increase in proportion of the DP T cells and was able to be classified into four phases on the basis of the qualitative and quantitative alteration.

Comparative analysis of human and macaque monkey CD4: differences in formaldehyde lability and conformation

Here we characterized macaque monkey CD4 by flow cytometry. The results showed that relatively lower fluorescence intensity was observed depending on the monoclonal antibodies (mAbs) used for staining; Leu-3a exhibited four-fold lower intensity than Nu-Th/i, and that formaldehyde fixation dramatically reduced fluorescence intensity of macaque CD4+ cells stained with Leu-3a but not of human cells. Nu-Th/i is therefore preferable for the analysis of macaque CD4. Pretreatment of either mAb inhibited the other mAb binding to human CD4. On the contrary, Nu-Th/i inhibited Leu-3a binding but Leu-3a poorly blocked Nu-Th/i binding to the macaque CD4. These results indicate that Leu-3a and Nu-Th/i epitopes are conserved in macaque CD4 but Leu-3a epitope is conformationally cryptic and/or fragile, resulting in the lower affinity. Amino acid sequence alignment of CD4 domain 1 shows that the substitutions outside the linear Leu-3a epitope may determine these characteristics of macaque CD4.

Differential expression of ADC mRNA during development and upon acid stress in soybean (Glycine max) hypocotyls

Arginine decarboxylase (ADC) is one of the key enzymes in the biosynthesis of putrescine in plants. The regulation of its activity depends on the physiological condition, developmental stage, and type of tissue. We have cloned ADC cDNA from soybean (Glycine max) hypocotyls to understand the regulation mechanisms of this enzyme activity. Using the cDNA clone, we examined the relationship between changes in the ADC activity and the level of ADC mRNA during development, in different tissues, and upon acid stress. The ADC activity began to increase 2 d after initiation of germination, reached a peak at the 5th d, and then declined. This change in the enzyme activity was preceded by similar changes in the level of the mRNA. The ADC activity was expressed tissue-specifically; this expression was well corelated with the mRNA content of the respective tissues. Incubation of the 5-d-old hypocotyls in pH 3 potassium phosphate solution caused a rapid increase in ADC activity. Within 2 h of acid treatment, the ADC activity increased more than threefold. This increase was also preceded by a corresponding increase in the mRNA content and was also regulated tissue-specifically. These results suggest that the change in the content of ADC mRNA has an important role in the regulation of the enzyme activity during early development, in different tissues, and upon acid stress.

Purification and characterization of arginine decarboxylase from soybean (Glycine max) hypocotyls

Arginine decarboxylase (EC 4.1.1.19) was purified from soybean, Glycine max, hypocotyls by a procedure which includes ammonium sulfate fractionation, acetone precipitation, gel filtration chromatography, and affinity chromatography. Using this procedure, ADC was purified to one band in non-denaturing PAGE. The purified ADC has an M(r) of 240 kDa based on gel filtration chromatography and is a trimer of identical subunits which has an estimated M(r) of 74 kDa based on SDS-PAGE. ADC is active between 30 and 50 degrees C and has a Km value of 46.1 microM. ADC is very sensitive to agmatine or putrescine but not to spermidine or spermine. In the presence of 0.5 mM agmatine (or putrescine), the enzyme activity was inhibited by 70%. However, at the same concentration of spermidine (or spermine), the enzyme activity was inhibited by only 10-20%.

Synthesis and antibacterial activities of new 1 beta-methylcarbapenems having a 1,3-diazabicyclo[3.3.0]octan-2,4-dione moiety

The synthesis of a new series of 1 beta-methylcarbapenems having a 1,3-diazabicyclo[3.3.0]octane-2,4-dione moiety is described. Their in vitro antibacterial activities against both Gram-positive and Gram-negative bateria are determined and the effect of substituent on the bicyclic ring as well as stereoisomerism was investigated.

Radiation therapy results for patients undergoing inappropriate surgery in the presence of invasive cervical carcinoma

Total vaginal or abdominal hysterectomy was considered an inadequate treatment method for invasive uterine cervix cancer. Usually the procedure was inadvertently performed on patients who were thought preoperatively to have benign or premalignant conditions. Between 1985 and 1993, 64 patients undergoing hysterectomy in the presence of invasive cervical cancer were treated with external radiation therapy and/or intracavitary radiotherapy. Preoperative diagnoses were carcinoma in situ (36), severe dysplasia (2), and early invasive cancer (14), and others were benign disease. Overall 5-year survival and relapse-free survival rates were 75.8 and 77.5%, respectively. For patients in retrospective stage IA, IB, and IIB (gross residual after surgery), overall 5-year survival rates were 90.9, 88.8, and 27.9%, respectively. Thirteen patients developed treatment failure; most of them (10/13) were patients with gross residual disease. Patients with early invasive cervical cancer (stage IA) had no treatment-related failure. Prognostic factors affecting survival by univariate analysis were retrospective stage (P = 0.0000) and preoperative diagnosis (P = 0.0021). Tumor histology was marginally significant factor (P = 0.0938). By multivariate analysis, only retrospective stage was significant prognostic factor (P = 0.0001). Adjuvant radiotherapy appears to be an effective treatment method for patients with presumed stage IA and IB after inadvertent hysterectomy. Survival for patients with gross disease remaining after inappropriate hysterectomy is poor. So, early cancer detection and proper management with precise pretreatment staging is necessary to avoid inadherent hysterectomy, especially in cases of gross residual disease.

Peripheral blood CD4+CD8+ lymphocytes in cynomolgus monkeys are of resting memory T lineage

In this study, we analyzed peripheral blood CD4+CD8+ double-positive (DP) lymphocytes in adult cynomolgus monkeys (Macaca fascicularis). Forty of 55 monkeys had > 5% of the peripheral blood DP subpopulation (9.3 +/- 5.9%; mean +/- SD) in peripheral blood lymphocytes (PBL) in contrast to a low percentage of peripheral blood DP cells in humans and mice. In a cross-sectional study, the peripheral blood DP cells were found to increase in proportion with age. To clarify whether peripheral blood DP lymphocytes were immature precursors released from thymus without prior differentiation, the expressions of CD8 chains and CD1b on peripheral blood DP lymphocytes were compared with those on thymocytes. The peripheral blood DP lymphocytes were CD8 alpha + beta- and CD1b-, while thymic DP lymphocytes were CD8 alpha + beta + and CD1b +, suggesting that the peripheral blood DP cells are extrathymic T lymphocytes. Furthermore, the peripheral blood DP lymphocytes exhibited a resting memory T cell phenotype with CD2hiCD3+CD28-CD29hiCD49dhiCD69-CD80lo. Taken together, adult cynomolgus monkeys possess a unique peripheral blood DP T cell subpopulation which expresses a resting memory T cell phenotype. In addition, similar phenotypic properties of DP lymphocytes were distributed in the spleen and lymph nodes, although the proportion was less in the spleen and much less in lymph nodes than in PBL.

Biological effects of drug-loaded biodegradable membranes for guided bone regeneration

The biological effects of drug-loaded biodegradable novel membrane for guided bone regeneration (GBR) was evaluated. The membranes were polyglycolic acid mesh coated with poly-L-lactic acid containing flurbiprofen, tetracycline or PDGF-BB. Porous structure was generated in the membranes by using a phase inversion method. The membrane was less toxic, nicely biodegradable and biocompatible for 8 wk after implantation in the dorsal skin of the rat. The drugs released from the membranes were shown to be effective for new bone formation. Tetracycline, flurbiprofen or PDGF-BB loaded membrane was markedly effective for osteoid tissue and new bone formation in the bony defect prepared in rat calvaria to compare with that by unloaded membrane. These results suggested that drug-loaded biodegradable barrier membrane might be a potential tool for GBR in periodontal therapy.