ImmunoPET and biodistribution with human epidermal growth factor receptor 3 targeting antibody 89Zr-RG7116

The humanized monoclonal antibody with high affinity for the human epidermal growth factor receptor (HER) 3, RG7116, is a glycoengineered, IgG1 class antibody. By labeling RG7116 with zirconium-89 (⁸⁹Zr) we aimed to visualize in vivo HER3 expression and study the biodistribution of this antibody in human tumor-bearing mice. Biodistribution of ⁸⁹Zr-RG7116 was studied in subcutaneously xenografted FaDu tumor cells (HER3-positive). Dose-dependency of ⁸⁹Zr-RG7116 organ distribution and specific tumor uptake was assessed by administering doses ranging from 0.05 to 10 mg/kg RG7116 to SCID/Beige mice. Biodistribution was analyzed at 24 and 144 h after injection. MicroPET imaging was performed at 1, 3, and 6 days after injection of 1.0 mg/kg ⁸⁹Zr-RG7116 in the FaDu, H441, QG-56 and Calu-1 xenografts with varying HER3 expression. The excised tumors were analyzed for HER3 expression. Biodistribution analyses showed a dose- and time-dependent ⁸⁹Zr-RG7116 tumor uptake in FaDu tumors. The highest tumor uptake of ⁸⁹Zr-RG7116 was observed in the 0.05 mg/kg dose group with 27.5%ID/g at 144 h after tracer injection. MicroPET imaging revealed specific tumor uptake of ⁸⁹Zr-RG7116 in FaDu and H441 models with an increase in tumor uptake over time. Biodistribution data was consistent with the microPET findings in FaDu, H441, QG56 and Calu-1 xenografts, which correlated with HER3 expression levels. In conclusion, ⁸⁹Zr-RG7116 specifically accumulates in HER3 expressing tumors. PET imaging with this tracer provides real-time non-invasive information about RG7116 distribution, tumor targeting and tumor HER3 expression levels.     

Thermophilic biofiltration of methanol and α-pinene

Biofiltration systems utilizing thermophilic (55C) bacteria were constructed and tested for the removal of methanol and α-pinene — two important volatile organic compounds (VOCs) in the forest products industry. Thermophilic bacterial mixtures that can degrade both methanol and α-pinene were obtained via enrichment techniques. Two bench-scale thermophilic biofiltration systems (1085 and 1824 cm³) were used to examine compound removals at different residence times, with influent concentrations of 110 ppmv methanol and 15 ppmv α-pinene. At a residence time of 10.85 min, the smaller system had removal efficiencies of >98% for methanol, but only 23% for α-pinene. The larger system was operated with the same parameters to evaluate residence time and surfactant effects on compound removals. At a residence time of 18.24 min, both methanol and α-pinene removal rates were ≥95%. However, α-pinene removal dropped to 26% at a residence time of 6.08 min; methanol removal was not affected. Subsequent addition of a surfactant mixture increased α-pinene removal to 94% at the shortest residence time. No residual α-pinene was detected with the support medium Celite R-635, indicating that the surfactant may increase mass transfer of α-pinene. Journal of Industrial Microbiology & Biotechnology (2001) 26, 127–133. Received 06 June 2000/ Accepted in revised form 09 November 2000     

Biofiltration for the removal and ‘detoxification’ of a complex mixture of volatile organic compounds

A study was performed to determine the effectiveness of using biofiltration for the removal of a complex mixture of volatile organic compounds (VOCs) air-stripped from petroleum hydrocarbons. A biofilter was constructed which contained 264 cm³ of packing material (Celite^? R-635). The unit was inoculated with a mixed culture containing a hydrocarbon-degrading Pseudomonas sp and an Alcaligenes sp. Several of the major compounds in the VOC mixture were monitored individually, along with the total VOCs, using gas chromatography. The average influent concentration of the VOC mixture was 320 ppmv and the average total VOC removal rate was over 56%, with the average removal rate of the monitored individual compounds ranging from 49–90%. After 30 days of operation the average overall removal rate was 69% and the removal of the major compounds averaged 92%. The toxicity and mutagenicity of the air stream was monitored using the Microtox and Ames assays, respectively. These data show marked decreases in toxicity and mutagenicity of the air stream as a result of the biofiltration treatment. The biofiltration system, therefore, was not only effective in removing VOCs from the air stream over an extended time-period, but was also effective in greatly reducing the toxicity and mutagenicity associated with the remaining VOCs. Received 03 July 1997/ Accepted in revised form 25 November 1997     

Pleiotropic effects on proliferation and mineralization of primary human adipose tissue-derived stromal cells induced by simvastatin

The circulating low-density lipoprotein concentration in blood can be reduced by the administration of statins. Frequently simvastatin (SV) is prescribed. Due to the reported pleiotropic effects of SV the aim of this study was to evaluate mineralization effects on human adipose tissue-derived stromal cells upon administration of SV. After informed consent human adipose tissue-derived stromal cells were obtained from tissue surplus of regular treatments of 14 individuals. According to established protocols after adding various SV concentrations (0.01 µM, 0.1 µM, 1.0 µM, 2.0 µM), alkaline phosphate (osteoblastic marker), mineralization capability and viability were determined at day 18, 21 and 28. The Kruskal–Wallis test was performed for statistical analysis. After adding SV a dose-dependent significant decreased viability and levels of alkaline phosphatase (p < 0.01) and a significantly increased mineralization (p < 0.01) of the primary cultures was recognized during the late mineralization stage. Mineralization of the human adipose tissue-derived stromal cells was induced by SV, possibly originated from alternative pathways than the alkaline phosphatase pathway. Further investigations should be performed regarding switching into the osteoblastic differentiation and as a possible source of cells that can be used as the basis for a potential bone graft substitute, which may allow an extension of the field of application.     

Discovery of potent azaindazole leucine-rich repeat kinase 2 (LRRK2) inhibitors possessing a key intramolecular hydrogen bond – Part 2

The discovery of disease-modifying therapies for Parkinson’s Disease (PD) represents a critical need in neurodegenerative medicine. Genetic mutations in LRRK2 are risk factors for the development of PD, and some of these mutations have been linked to increased LRRK2 kinase activity and neuronal toxicity in cellular and animal models. As such, research towards brain-permeable kinase inhibitors of LRRK2 has received much attention. In the course of a program to identify structurally diverse inhibitors of LRRK2 kinase activity, a 5-azaindazole series was optimized for potency, metabolic stability and brain penetration. A key design element involved the incorporation of an intramolecular hydrogen bond to increase permeability and potency against LRRK2. This communication will outline the structure-activity relationships of this matched pair series including the challenge of obtaining a desirable balance between metabolic stability and brain penetration.     

Stratification,Blinding and Placebo Effect in a Randomized,Double Blind Placebo-controlled Clinical Trial of Gold Bead Implantation in Dogs with Hip Dysplasia

The purpose of this study was to investigate the need for and choice of stratification factors, and the effects of blinding and placebo in a clinical experiment. Eighty dogs with canine hip dysplasia (CHD) were included in a randomized, placebo-controlled and double blind clinical trial with stratified parallel group design, in which body weight and degree of CHD were used as stratification factors. Thirty-eight dogs were allocated to gold bead implantation and 42 to placebo. After six months, 33 of the 42 placebo-treated dogs received gold bead implantation in an open study lasting a further 18 months. The main outcome variable in the study was change in pain signs of CHD as assessed by the owner. No significant difference in the main outcome variable, regardless of the treatment given, could be detected in the two chosen stratification factors. The only factor to influence the main outcome variable significantly was age. The blinding procedure used in the study, in which 60% of the owners correctly guessed the treatment given, was found sufficient. Of those who guessed the treatment erroneously, 88% believed the treatment given was gold bead implantation. The treatment efficacy after six months in the blinded treatment group was found to be significantly larger compared to the efficacy obtained in the open study. A significant placebo effect was therefore detected. Conclusion and Clinical Relevance: The age of the dogs influenced the outcome of the CHD treatment, and is recommended as a stratification factor. A significant placebo effect has to be expected and an optimal blinding procedure is necessary in similar clinical studies.     

Microstructure and mineral composition of dystrophic calcification associated with the idiopathic inflammatory myopathies

Introduction  

Calcified deposits (CDs) in skin and muscles are common in juvenile dermatomyositis (DM), and less frequent in adult DM. Limited information exists about the microstructure and composition of these deposits, and no information is available on their elemental composition and contents, mineral density (MD) and stiffness. We determined the microstructure, chemical composition, MD and stiffness of CDs obtained from DM patients.     

Characterization of a maltose transport system in Clostridium acetobutylicum ATCC 824

The utilization of maltose by Clostridium acetobutylicum ATCC 824 was investigated. Glucose was used preferentially to maltose, when both substrates were present in the medium. Maltose phosphoenolpyruvate (PEP)-dependent phosphotransferase system (PTS) activity was detected in extracts prepared from cultures grown on maltose, but not glucose or sucrose, as the sole carbon source. Extract fractionation and PTS reconstitution experiments revealed that the specificity for maltose is contained entirely within the membrane in this organism. A putative gene system for the maltose PTS was identified (from the C. acetobutylicum ATCC 824 genome sequence), encoding an enzyme II^Mal and a maltose 6-phosphate hydrolase. Journal of Industrial Microbiology & Biotechnology (2001) 27, 298–306. Received 12 September 2000/ Accepted in revised form 30 November 2000     

Microbes in beach sands: integrating environment,ecology and public health

Beach sand is a habitat that supports many microbes, including viruses, bacteria, fungi and protozoa (micropsammon). The apparently inhospitable conditions of beach sand environments belie the thriving communities found there. Physical factors, such as water availability and protection from insolation; biological factors, such as competition, predation, and biofilm formation; and nutrient availability all contribute to the characteristics of the micropsammon. Sand microbial communities include autochthonous species/phylotypes indigenous to the environment. Allochthonous microbes, including fecal indicator bacteria (FIB) and waterborne pathogens, are deposited via waves, runoff, air, or animals. The fate of these microbes ranges from death, to transient persistence and/or replication, to establishment of thriving populations (naturalization) and integration in the autochthonous community. Transport of the micropsammon within the habitat occurs both horizontally across the beach, and vertically from the sand surface and ground water table, as well as at various scales including interstitial flow within sand pores, sediment transport for particle-associated microbes, and the large-scale processes of wave action and terrestrial runoff. The concept of beach sand as a microbial habitat and reservoir of FIB and pathogens has begun to influence our thinking about human health effects associated with sand exposure and recreational water use. A variety of pathogens have been reported from beach sands, and recent epidemiology studies have found some evidence of health risks associated with sand exposure. Persistent or replicating populations of FIB and enteric pathogens have consequences for watershed/beach management strategies and regulatory standards for safe beaches. This review summarizes our understanding of the community structure, ecology, fate, transport, and public health implications of microbes in beach sand. It concludes with recommendations for future work in this vastly under-studied area.     

A new type of papillomavirus DNA, its presence in genital cancer biopsies and in cell lines derived from cervical cancer.

DNA of a new papillomavirus type was cloned from a cervical carcinoma biopsy. Two EcoRI clones of 7.8 and 6.9 kb in length were obtained, the latter contained a 900-bp deletion. The BamHI fragments of both clones were used to characterize the DNA. It represents a distinct type of papillomavirus as determined by its size, its cross-hybridization with DNA of other papillomavirus types under conditions of low stringency only, the co-linear alignment of its genome with HPV 6 and HPV 16 prototypes and its occasional occurrence as oligomeric episomes. We tentatively propose to designate it as HPV 18. DNA hybridizing with HPV 18 under stringent conditions was detected in 9/36 cervical carcinomas from Africa and Brazil, in 2/13 cervical tumors from Germany and 1/10 penile carcinomas. Benign tumors (17 cervical dysplasias, 29 genital warts), eight carcinomata in situ and 15 biopsies of normal cervical tissue were devoid of detectable HPV 18 DNA. HPV 18-related DNA was found, however, in cells of the HeLa, KB and C4-1 lines all derived from cervical cancer. The state of the viral DNA was investigated in four cervical cancer biopsies. The data reveal that the DNA might be integrated into the host cell genome. One tumor provided evidence for head to tail tandem repeats some of which persisted as circular episomes.