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Presents a study conducted on the activities of starch hydrolytic enzyme activities following defoliation of white clover. Effect of defoliation on growth and defoliation on stolon protein concentrations; Detailed information on the methodology used to conduct the study; Discussion based on the results of the study.

Introduction: Basic fibroblast growth factor (bFGF) and hepatocyte growth factor (HGF) are important positive regulators of tumor growth and angiogenesis. This study was designed to assess the effect of bFGF and HGF infusion on tumor growth and metastases in a syngeneic, rat colon adenocarcinoma tumor model. Methods: Liver tumors were established in each of 21 BD9 rats via surgical, subcapsular implantation of a 1.0 mm3 piece of a subcutaneously grown DHD/K12/TRb tumor. Test groups were infused systemically with 5 μg/day/rat bFGF or 0.5 μg/day/rat HGF via osmotic pump; and controls received saline. At 28 days all animals were killed and examined. Tumor volume was calculated as π[a2 × b]/6, where a is shorter length and b the longer length. Liver and lung specimens were fixed in zinc formalin and embedded in paraffin for H&E staining and immunohistochemical study. Results: On histologic examination, tumor cells were seen to grow along blood vessel branches after infusion bFGF and HGF. Both VEGF and Flk-1 expression was strong cytoplasmic staining in cancer cells from hepatic, peritoneal and lung metastases. Conclusion: While both bFGF and HGF appear to induce an increase in tumor growth in this model, the effect of bFGF was marked. Similarly, HGF appeared to stimulate the development of distant metastases, though not reaching significance, while bFGF produced local and distant metastases with statistically significant increase in lung metastases. This rat colon adenocarcinoma cell line expressed VEGF and its receptor Flk-1. Further studies are required to evaluate the mechanism of tumor growth and metastasis stimulation. TABLE—ABSTRACT P8Control (n = 7)bFGF (n = 7)HGF (n = 6&ast;)P valueTumor volume (mm3)48.8 ± 17.685.1 ± 25.0†59.3 ± 26.9†<.05Intrahepatic mets03/7‡0‡=.19Peritoneal mets03/7‡1/6‡=.19Lung mets&ast;&ast;05/7‡1/6‡=.02&ast;One rat in this group died at postoperative two weeks.†,‡bFGF group vs control group by Kruskal Wallis test. [Copyright &y& Elsevier]

Abstract: The in vivo kinematics of 10 patients after combined anterior cruciate ligament reconstruction (ACLR group) and Oxford unicompartmental knee arthroplasty (UKA) was compared to those of 10 Oxford UKA patients with an intact ACL (ACLI group) and a group of 22 normal knees. The kinematics during a step-up exercise and a deep knee bend exercise was measured using a fluoroscopic technique. The patellar tendon angle (PTA) to knee flexion angle relationship during both exercises was similar for all three groups of subjects. For the UKA groups the pattern of mobile bearing movement during both exercises was similar. This study demonstrates that normal knee kinematics is achieved in the ACL deficient arthritic knee following ACLR and UKA. As a result these patients, who tend to be young and high demand, have excellent outcome and achieve high levels of function. As the relative position of the components and thus component loading are similar to the ACLI UKA, we would expect similar long term survival. [Copyright &y& Elsevier]

The effect of nanotopography on a range of Ti oxide surfaces was determined. Flat Ti, 3%, 19%, 30% and 43% topography densities of 110 nm high hemispherical protrusions were cultured in contact with primary derived human macrophages and osteoblasts in single culture models.Prior to introduction of the test substrate the phenotype and optimum conditions for in vitro cell culture were established. The cellular response was investigated and quantified by assessments of cytoskeletal development and orientation, viable cell adhesion, cytokine production and release and RT-PCR analysis of osteogenic markers.The tested nanotopographies did not have a statistically significant effect on viable cell adhesion and subsequent cytoskeletal formation. Surface chemistry was the dominant factor as established via incorporation of a tissue culture polystyrene, TCPS, control. The topography surfaces induced a release of chemotactic macrophage activation agents at 1 day in conjunction with stress fibre formation and a subsequent fibronectin network formation. Osteoblasts migrated away from the topography surfaces to the exposed TCPS within the wells during the 7-day period. [Copyright &y& Elsevier]

We have assessed the effect of elevated concentrations of hydroxyphenylpyruvic acid (HPPA), hydroxyphenyllactic acid (HPLA) and tyrosine, on a range of chemistry tests in serum and urine to explore the potential for chemical interference on routine laboratory analyses in patients with alkaptonuria (AKU) treated with nitisinone and similarly implications for patients with hereditary tyrosinemia type 1 (HT-1). HPPA, HPLA and tyrosine were added separately to pooled serum from subjects without AKU in a range of assays with Roche Modular chemistries. Effects on urine were assessed by changes in urine strip chemistries after mixing a positive control urine with various amounts of the test compounds and reading on a Siemens urine strip meter. No significant effect (p > 0.1) was observed up to 225 μmol/L of HPPA and HPLA, and up to 5000 μmol/L tyrosine, on any of the serum-based assays including those with peroxidase-coupled reaction systems of enzymatic creatinine, urate, total cholesterol, HDL cholesterol and triglyceride. Both the monohydroxy HPPA, and the dihydroxy homogentisic acid (HGA), at increased urine concentrations typical of nitisinone-treated AKU and non-treated AKU respectively, did however show marked negative interference in strip assays for glucose and leucocytes; i.e. those with peroxide-linked endpoints. The effect of increased HPLA was less marked. In patients with AKU or on nitisinone treatment and HT-1 patients on nitisinone, urine strip chemistry testing should be used sparingly, if at all, to avoid false negative reporting. It is recommended that urine assays should be organised with a suitable specialist laboratory. • Alkaptonuria treated with nitisinone results in reduction of HGA and marked increases in HPPA, HPLA, and tyrosine • The elevated concentrations of HPPA, HPLA and tyrosine did not interfere with a wide range blood/serum assays used in clinical practice • Increased urinary HGA and HPPA interfered with some urine test strip chemistries • The oxidase-based urine assays showed most suppression of response by HGA and HPPA • Urine strip tests should be avoided in patients with alkaptonuria and patients on nitisinone [ABSTRACT FROM AUTHOR]

Abstract Objective Concerns exist over hypertyrosinaemia that is observed following treatment with nitisinone. It has been suggested that tyrosine may compete with tryptophan for uptake into the central nervous system, and or inhibit tryptophan hydroxylase activity reducing serotonin production. At the National Alkaptonuria (AKU) Centre nitisinone is being used off-licence to treat AKU, and there is uncertainty over whether hypertyrosinaemia may alter mood. Herein results from clinical and biochemical assessments of depression in patients with AKU before and after treatment with nitisinone are presented. Patients and methods 63 patients were included pre-nitisinone treatment, of these 39 and 32 patients were followed up 12 and 24 months after treatment. All patients had Becks Depression Inventory-II (BDI-II) assessments (scores can range from 0 to 63, the higher the score the more severe the category of depression), and where possible urinary monoamine neurotransmitter metabolites and serum aromatic amino acids were measured as biochemical markers of depression. Results Mean (±standard deviation) BDI-II scores pre-nitisinone, and after 12 and 24 months were 10.1(9.6); 9.8(10.0) and 10.5(9.9) (p ≥ 0.05, all visits). Paired scores (n = 32), showed a significant increase at 24 months compared to baseline 10.5(9.9) vs. 8.6 (7.8) (p = 0.03). Serum tyrosine increased at least 6-fold following nitisinone (p ≤ 0.0001, all visits), and urinary 3-methoxytyramine (3-MT) increased at 12 and 24 months (p ≤ 0.0001), and 5-hydroxyindole acetic acid (5-HIAA) decreased at 12 months (p = 0.03). Conclusions BDI-II scores were significantly higher following 24 months of nitisinone therapy in patients that were followed up, however the majority of these patients remained in the minimal category of depression. Serum tyrosine and urinary 3-MT increased significantly following treatment with nitisinone. In contrast urinary 5-HIAA did not decrease consistently over the same period studied. Together these findings suggest nitisinone does not cause depression despite some observed effects on monoamine neurotransmitter metabolism. [ABSTRACT FROM AUTHOR]

Highlights: [•] Developed LC–MS/MS method for homogentisic acid and tyrosine in human urine. [•] Validated in both acidified and non-acidified urine matrices. [•] Applicable for diagnosing patients with alkaptonuria. [•] Applicable for monitoring response to therapy in treatment of alkaptonuria. [•] Validated according to European Medicines Agency Guidelines. [ABSTRACT FROM AUTHOR]

Abstract: Laminaria digitata is a highly prevalent kelp growing off the coast of the UK but has rarely been considered as a source of biomass to date. This study shows it can be used as a feedstock in both ethanol fermentation and anaerobic digestion for methane production. The study optimised several parameters in the fermentation of L. digitata and investigated the suitability of the macroalgae through the year using samples harvested every month. For both methane and ethanol production, minimum yields were seen in material harvested in March when the carbohydrates laminarin and mannitol were lowest. July material contained the highest combined laminarin and mannitol content and maximum yields of 167mL ethanol and 0.219m3 kg−1 L. digitata. [Copyright &y& Elsevier]

Abstract: To avoid negative impacts on food production, novel non-food biofuel feedstocks need to be identified and utilised. One option is to utilise marine biomass, notably fast-growing, large marine ‘plants’ such as the macroalgal kelps. This paper reports on the changing composition of Laminaria digitata throughout it growth cycle as determined by new technologies. The potential of Laminaria sp. as a feedstock for biofuel production and future biorefining possibilities was assessed through proximate and ultimate analysis, initial pyrolysis rates using thermo-gravimetric analysis (TGA), metals content and pyrolysis gas chromatography–mass spectrometry. Samples harvested in March contained the lowest proportion of carbohydrate and the highest ash and alkali metal content, whereas samples harvested in July contained the highest proportions of carbohydrate, lowest alkali metals and ash content. July was therefore considered the most suitable month for harvesting kelp biomass for thermochemical conversion to biofuels. [ABSTRACT FROM AUTHOR]

Abstract: Peroxisome proliferator-activated receptors (PPARs) are members of the nuclear steroid hormone superfamily and exist in three isoforms: PPARα, β and γ, each with specific functions. In this study, we have investigated the expression of PPARs by human osteoclast precursors and osteoclasts generated in vitro. In addition, the effects of fibrates and isoform-specific PPAR agonists on osteoclast formation and resorption in vitro were determined. Human peripheral blood mononuclear cells (PBMCs) were stimulated with human recombinant RANKL and M-CSF to generate osteoclasts. RNA was extracted at days 0, 7, 14 and 21 and RT-PCR for all three PPAR isoforms demonstrated their expression throughout this culture period. To determine the effect on osteoclast formation, PPAR agonists (10−8 M to 10−5 M) were added from the beginning of the culture until day 14 and the number of multinucleated osteoclasts counted. The effect of PPAR agonists on osteoclast function was similarly determined by treating mature, multinucleated osteoclasts cultured on dentine wafers with PPAR agonists (10−8 M to 10−5 M) for 7 days and quantifying resorption. Bezafibrate and fenofibrate, which non-discriminately activate all PPAR isoforms, significantly inhibited the formation of multinucleated osteoclasts from PBMC in vitro. Bezafibrate treatment of mature osteoclast resulted in 50% inhibition (at 10−8 M and 10−7 M) of resorption, yet fenofibrate had no significant effect. Activation of individual PPARs with isoform-specific agonist (GW9578, L165041 and ciglitizone which preferentially activate PPARα, β and γ respectively) resulted in significant dose-dependent inhibition of multinucleated osteoclast formation. Divergent effects on osteoclast resorption were observed; GW9578 had no significant effect on resorption, whereas ciglitizone and L165041 dose-dependently inhibited and stimulated resorption, respectively. These data show for the first time expression of all three PPAR isoforms throughout the development and maturation period of osteoclasts generated from human PBMCs. In addition, we demonstrate that isoform-specific PPAR agonists have strong effects on multinucleation and highly variable effects on bone resorption. In conclusion, this study highlights the potential of PPARs as therapeutic targets in diseases with accelerated osteoclast formation and resorption. [Copyright &y& Elsevier]

Nucleotides such as adenosine triphosphate (ATP) and uridine triphosphate (UTP) exist in the extracellular environment where they are agonists at P2 receptors. Both P2Y G-protein-coupled receptors and P2X ligand-gated ion channels are expressed by osteoblasts and osteoclasts, reflected in the diverse nucleotide-induced effects reported to occur in bone. Previous reports have implicated ATP as a proresorptive agent; however, these studies were unable to determine whether ATP mediated its actions directly on osteoclasts, or indirectly via osteoblasts. The development of techniques to generate human osteoclasts in vitro has allowed us to further investigate the intriguing role of extracellular nucleotides with regard to osteoclast activity. This study reports that nearly all P2-receptor-subtype mRNAs were expressed throughout human osteoclast development, and provides evidence for functional P2 receptor expression by these cells. In cultures of human osteoclasts alone, neither ATP nor UTP affected the quantity of resorption by these cells; however, in cocultures of osteoblast-like UMR-106 cells and human osteoclasts, ATP, but not UTP, greatly enhanced resorption, indicating a role for osteoblasts in mediating the proresorptive effects of ATP. Furthermore, ATP, but not UTP, elevated receptor activator of nuclear factor-κB ligand (RANKL) mRNA and protein expression by UMR-106 cells. These data are consistent with observations that UMR-106 cells predominantly express P2Y1 with low expression of P2Y2, thereby explaining the response to ATP and not UTP, and further substantiating the involvement of osteoblasts in ATP-induced effects on osteoclasts. These results significantly advance our understanding of the role of P2 receptors in bone, and indicate that local-acting ATP may play a pivotal role in osteoclast activation at bone-resorbing sites by inducing elevated expression of RANKL. [Copyright &y& Elsevier]

Examines the role of thrombospondin-2 in the regulation of bone resorption. Activated platelets' secretion of thrombospondin; Similarities in the mechanisms of resorption.

Characterizes the novel bone antigens using monoclonal antibodies. Methods used in screening conditioned hybridoma supernatants; Proteins associated with skeletal tissues; Factors involved in bone antigen expression at different levels of maturity.

Abstract: Newer designs of total knee arthroplasty (TKA), through the use of added degrees of constraint, attempt to provide a “guided motion” to restore more normal and predictable kinematics. Two such design philosophies are the posterior stabilised (PS) using a cam–post and the medial pivot (MP) concepts. Knee kinematics of 12 patients with a PS TKA, 13 subjects with a MP TKA and 10 normal subjects were compared. For kinematic assessment, patients underwent fluoroscopic assessment of the knee during a step-up exercise and deep knee bend. Fluoroscopic images were corrected for distortion and assessed using 3D model fitting to determine relative 3D motion, and a 2D method to measure the patellar tendon angle (PTA) as function of knee flexion. For the PS design the cam–post mechanism engaged between 70° and 100° flexion. Between extension and 50° there was forward motion of the contact points. Beyond 60° both condyles rolled moved posteriorly. The majority of the external rotation of the femur occurred between 50° and 80°. The PTA was lower than normal in extension and higher than normal in flexion. The MP exhibited no anterior movement throughout the rage of motion. The medial condyle moved minimally. The lateral contact point moved posteriorly from extension to flexion. The femur rotated externally throughout the range of flexion analysed. The PTA was similar to normal from extension to mid flexion and then higher than normal beyond to high flexion. The PS design fails to fully restrain paradoxical anterior movement and although the cam engages, it does not contribute significantly to overall rollback. The MP knee does not show significant anterior movement, the medial pivot concept appears to achieve near normal kinematics from extension to 50° of knee flexion. However, the results show that at high flexion this design does not achieve normal knee kinematics. [Copyright &y& Elsevier]