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Mature osteoclasts express the vitamin D receptor (VDR) and are able to synthesise and respond to 1,25(OH) 2 D 3 via CYP27B1 enzyme activity. Whether vitamin D signalling within osteoclasts is necessary for the regulation of osteoclastic bone resorption in an in vivo setting is unclear. To determine the requirement for the VDR- and CYP27B1-mediated activity in mature osteoclasts, conditional deletion mouse models were created whereby either Vdr or Cyp27b1 gene was inactivated by breeding either Vdr fl/fl or Cyp27b1 fl/fl mice with Cathepsin K-Cre transgenic mice (Cstk Cre ) to generate Ctsk Cre /Vdr -/- and Ctsk Cre /Cyp27b1 -/- mice respectively. To account for potential Ctsk Cre -meaited off-target deletion of Vdr, Dmp1 Cre were also used determine the effect of Vdr deletion in osteocytes. Furthermore, Ctsk Cre /Vdr -/- mice were ovariectomised (OVX) to assess the role of VDR in osteoclasts under bone-loss conditions and bone marrow precursor cells were cultured under osteoclastogenic conditions to assess osteoclast formation. Six-week-old Ctsk Cre /Vdr -/- female mice demonstrated a 15% decrease in femoral BV/TV (p & #60; 0.05). In contrast, BV/TV remained unchanged in Ctsk Cre /Cyp27b1 -/- mice as well as in Dmp1 Cre /VDR -/- mice. When Ctsk Cre /Vdr -/- mice were subjected to OVX, the bone loss that occurred in Ctsk Cre /Vdr -/- was predominantly due to a diminished volume of thinner trabeculae when compared to control levels. These changes in bone volume in Ctsk Cre /Vdr -/- mice occurred without an observable histological change in osteoclast numbers or size. However, while cultured bone marrow-derived osteoclasts from Ctsk Cre /Vdr -/- mice were marginally increased when compared to VDR fl/fl mice, elevated expression of genes such as Cathepsin K, Nfatc1 and VATPase was observed. Collectively, these data indicate that the absence of VDR in mature osteoclasts causes exacerbated bone loss in young mice and during OVX which is associated with enhanced osteoclastic activity and without increased osteoclastogenesis. Refereed/Peer-reviewed

The small genomes of most viruses make it difficult to fully capture viral diversity in metagenomes dominated by DNA from cellular organisms. Viral size-fraction metagenomics (viromics) protocols facilitate enrichment of viral DNA from environmental samples, and these protocols typically include a DNase treatment of the post-0.2 μm viromic fraction to remove contaminating free DNA prior to virion lysis. However, DNase may also remove desirable viral genomic DNA (e.g., contained in virions compromised due to frozen storage or laboratory processing), suggesting that DNase-untreated viromes might be useful in some cases. In order to understand how virome preparation with and without DNase treatment influences the resultant data, here we compared 15 soil viromes (7 DNase-treated, 8 untreated) from 8 samples collected from agricultural fields prior to tomato planting. DNase-treated viromes yielded significantly more assembled viral contigs, contained significantly less non-viral microbial DNA, and recovered more viral populations (vOTUs) through read mapping. However, DNase-treated and untreated viromes were statistically indistinguishable, in terms of ecological patterns across viral communities. Although results suggest that DNase treatment is preferable where possible, in comparison to previously reported total metagenomes from the same samples, both DNase-treated and untreated viromes were significantly enriched in viral signatures by all metrics compared, including a ~225 times greater proportion of viral reads in untreated viromes compared to total metagenomes. Thus, even without DNase treatment, viromics was preferable to total metagenomics for capturing viral diversity in these soils, suggesting that preparation of DNase-untreated viromes can be worthwhile when DNase treatment is not possible.ImportanceViromics is becoming an increasingly popular method for characterizing soil viral communities. DNase treatment of the viral size fraction prior to DNA extraction is meant to reduce contaminating free DNA and is a common step within viromics protocols to ensure sequences are of viral origin. However, some samples may not be amendable to DNase treatment due to viral particles being compromised either in storage (i.e. frozen) or during other sample processing. To date, the effect of DNase treatment on the recovery of viruses and downstream ecological interpretations of soil viral communities is not thoroughly understood. This work sheds light on these questions and indicates that while DNase treatment of soil viromes improves recovery of viral populations, this improvement is modest in comparison to the gains made by viromics over total soil metagenomics. Further, DNase treatment may not be necessary to observe the ecological patterns structuring soil viral communities.

The bis(imino)pyridine iron complex, for the first time, is developed as an effective metal carbene catalyst for carbene transfer reactions of donor–acceptor diazo compounds., The bis(imino)pyridine iron complex, for the first time, is developed as an effective metal carbene catalyst for carbene transfer reactions of donor–acceptor diazo compounds. Its broad catalytic capability is demonstrated by a range of metal carbene reactions, from cyclopropanation, cyclopropenation, epoxidation, and Doyle–Kirmse reaction to O–H insertion, N–H insertion, and C–H insertion reactions. The asymmetric cyclopropanation of styrene and methyl phenyldiazoacetate was successfully achieved by the new chiral bis(imino)pyridine iron catalyst, which delivers a new gateway for the development of chiral iron catalysis for metal carbene reactions.

The bis(imino)pyridine iron complex, for the first time, is developed as an effective metal carbene catalyst for carbene transfer reactions of donor-acceptor diazo compounds. Its broad catalytic capability is demonstrated by a range of metal carbene reactions, from cyclopropanation, cyclopropenation, epoxidation, and Doyle-Kirmse reaction to O-H insertion, N-H insertion, and C-H insertion reactions. The asymmetric cyclopropanation of styrene and methyl phenyldiazoacetate was successfully achieved by the new chiral bis(imino)pyridine iron catalyst, which delivers a new gateway for the development of chiral iron catalysis for metal carbene reactions.

Phytophthora andina is a heterothallic plant pathogen of Andean solanaceous hosts and is an interspecific hybrid of P. infestans and an unknown Phytophthora species. The objective of this study was to estimate the nuclear DNA content of isolates in three clonal lineages of P. andina relative to P. infestans Twelve isolates of P. andina and six isolates of P. infestans were measured for nuclear DNA content by propidium iodide-stained flow cytometry. We found that the DNA content of P. andina was similar but slightly smaller, on average, than that of our sample of P. infestans isolates. This is consistent with P. andina being a homoploid hybrid rather than allopolyploid hybrid. Nuclear DNA content was more variable among a smaller sample of P. infestans isolates, including a putative triploid isolate from Mexico, but small differences in nuclear DNA content were also observed among P. andina isolates. Both species appear to be able to tolerate significant variation in genome size.

A novel process for the fixed-bed deoxygenation of a model bio-oil compound in supercritical media at mild pressures (tens of bars) is presented. As an example, nonanal deoxygenation over Pt/Al 2 O 3 catalyst in supercritical n-hexane (T c = 234.45 °C, P c = 30.2 bar) with excess hydrogen (molar H 2 /nonanol in feed = 57) at 300 °C provides steady conversions of approximately 60% over a pressure range of 7—80 bar with approximately 40% selectivity to C 8 and C 9 hydrocarbons, at liquid hourly space velocities of 80 g nonanal•(g Pt) ―1 •h ―1 . Further, the conversions display only a mild temperature dependence. This suggests that for the conditions under study, the reaction is limited by mass transfer of nonanal (limiting reactant) from the bulk fluid phase to the catalyst particle. Among the alkanes, the selectivity to the decarbonylation product (n-octane) is higher at all pressures relative to the hydrogention product (n-nonane). However, the selectivities toward nonane and nonanol increase relative to the decarbonylation product (n-octane) at higher reactor pressures, attributed to the enhanced hydrogen partial pressures at supercritical conditions. Effective rate constants, estimated from a simple isothermal packed-bed reactor model that assumes first-order dependence on nonanal concentration, decrease exponentially as the pressure is tuned from subcritical pressures (gaslike properties) to supercritical pressures (liquidlike properties). This decrease is characteristic of the pressure dependence of the external mass transfer coefficient. Mass transfer coefficients, predicted using published correlations, are of the same order of magnitude as the effective rate constants, further affirming that the measured reaction rates are controlled by external mass transfer.

Tunable solvents such as gas-expanded liquids offer unique opportunities as benign and economic reaction media. We have improved the turnover frequency of a water-soluble catalyst system by a factor of 85 for the hydroformylation of 1-octene by using a tunable solvent system, which also increases substrate solubility. In our approach, the reaction is run homogeneously in a miscible water−organic solution, and after reaction, CO2 is used as a “miscibility switch” for efficient product and catalyst recovery. Two water-soluble ligands, TPPTS (tris(3-sulfophenyl)phosphine) and TPPMS ((3-sulfophenyl)diphenylphosphine), were compared to triphenylphosphine for hydroformylation activity of their rhodium complexes. The catalyst was recycled three times with no loss of activity.

Gas-expanded liquids (GXLs) form a unique class of environmentally benign solvents that offer many of the benefits of both organic liquids and supercritical fluids. A more complete understanding of the interactions between the gas, the organic liquid, and solutes at the molecular level will enable the full exploitation of GXLs. Combining kinetic and solvatochromic studies, we have developed a comprehensive multiparameter approach to add insight into the molecular interactions related to a Diels−Alder reaction in CO2-expanded acetonitrile. We have studied the kinetics of the Diels−Alder reaction of anthracene and 4-phenyl-1,2,4-triazoline-3,5-dione as a function of solvent composition using in situ high-pressure fluorescence spectroscopy. We have also measured the values of the Kamlet−Taft solvatochromic parameters π* (dipolarity/polarizibility), α (hydrogen bonding acidity), and β (hydrogen bonding basicity) in CO2-expanded acetonitrile using in situ high-pressure UV/vis spectroscopy. A linear solvation e...

Vitamin D activity requires an adequate vitamin D status as indicated by the serumlevel of 25-hydroxyvitamin D and appropriate expression of genes coding for vitamin D receptor and 25-hydroxyvitamin D 1α-hydroxylase, the enzymewhich converts 25-hydroxyvitamin D to 1,25-dihydroxyvitamin D. Vitamin D deficiency contributes to the aetiology of osteomalacia and osteoporosis. The key element of osteomalacia, or rickets in children, is a delay in mineralization. It can be resolved by normalisation of plasma calcium and phosphate homeostasis independently of vitamin D activity. The well characterised endocrine pathway of vitamin D metabolism generates plasma 1,25-dihydroxyvitamin D and these endocrine activities are solely responsible for vitamin D regulating plasmacalciumand phosphate homeostasis and protection against osteomalacia. In contrast, a large body of clinical data indicate that an adequate serum 25-hydroxyvitamin D level improves bone mineral density protecting against osteoporosis and reducing fracture risk. Recent research demonstrates that the three major bone cell types have the capability to metabolise 25-hydroxyvitamin D to 1,25-dihydroxyvitamin D to activate the vitamin D receptor and modulate gene expression. Dietary calcium intake interacts with vitamin D metabolism at both the renal and bone tissue levels to direct either a catabolic action on bone through the endocrine system when calcium intake is inadequate or an anabolic action through a bone autocrine or paracrine system when calcium intake is sufficient. Refereed/Peer-reviewed

Advanced oxidation processes (AOPs) are aggressive chemical oxidation techniques that are characterized by the formation of hydroxyl radicals. This treatability study evaluated the performance of the following AOPs for treating cyanide-contaminated wastewater from an engine manufacturing company: low-pressure ultraviolet (LPUV) light/ozone (O 3 ), medium-pressure UV (MPUV)/hydrogen peroxide (H 2 O 2 ), MPUV/O 3 /H 2 O 2 , and peroxone (combination of O 3 and H 2 O 2 ). A bench-scale reactor was used to examine the relative effectiveness of each AOP for removal of both cyanide and total organic carbon (TOC) from the wastewater. Initial cyanide concentration of the water was 0.6 mg/L. The experiments were run for 1 h. The LPUV/O 3 process removed 18 and 60% of the initial cyanide and TOC in the wastewater, respectively. The changes in TOC observed with the evaluated peroxone schemes (5% O 3 /100 mg/L H 2 O 2 and 1% O 3 /100 mg/L H 2 O 2 ) were almost identical to those seen with the LPUV/O 3 system. The combination of medium-pressure UV and 500 mg/L H 2 O 2 peformed best among the AOPs in the study with respect to cyanide removal. Surprisingly low removal of TOC was observed, indicating a low potential for hydroxyl radicals to remove the organic fraction from this wastewater. A combination of all the results indicates that the main mechanisms of TOC and cyanide removal are volatilization and photolysis, respectively. The results of the treatability study were used in designing a water treatment system currently in operation at the engine manufacturing facility.

Several radionuclide imaging agents have been used for assessing the presence of myocardial viability. These include Tl-201 chloride, Tc-99m sestamibi, and Tc-99m teboroxime. Currently, the most reliable indicator is F-18 FDG, which accumulates in severely hypoperfused myocardium, indicating preserved metabolic activity. The presence of chronically ischemic myocardium that has preserved metabolic activity is referred to as "hibernating" myocardium. In this series, the ability of Tl-201, sestamibi, and teboroxime to establish the existence of viable myocardium was compared with that of F-18 FDG. Seventy-seven patients with ischemic cardiomyopathy were referred for determination of myocardial viability. FDG images were compared with representative resting blood-flow images obtained from either: 1) 24 hour Tl-201 reinjection-redistribution images, 2) resting sestamibi blood-flow images, or 3) early images from resting teboroxime washout analysis. Tl-201 was found to underestimate myocardial viability in 41% of patients, Tc-99m sestamibi underestimated viability in 38% of patients, and Tc-99m teboroxime underestimated viability in 26% of patients. There was no significant difference in the prediction of viable myocardium among the three radiopharmaceuticals, as all three underestimated myocardial viability.

The potential applications of supercritical reaction media in heterogeneous catalysis have greatly expanded in recent years to include industrially significant reactions such as selective catalytic oxidations (fine and agricultural chemicals), fixed-bed hydrogenations (pharmaceuticals, chemical intermediates), polymerizations, hydroformylations (petrochemical), and solid-acid catalyzed alkylations (petroleum refining). The near-critical region (roughly 1.05-1.2 Tc; and 0.9 - 2.0 Pc) provides access to unique fluid properties (liquid-like densities and gas-like transport properties) that have been exploited in heterogeneous catalytic systems in numerous ways such as these: eliminating oxygen or hydrogen solubility limitations in the liquid phase of multiphase reaction systems; enhanced desorption and transport of heavy molecules (such as coke precursors) in mesoporous catalysts alleviating pore-diffusion limitations and improving catalyst effectiveness; in situ removal of primary reaction products maximizing their selectivity; enhanced heat capacity ameliorating the problem of parametric sensitivity in exothermic fixed-bed reactors; and facile separation of reactants and products. Supercritical reaction systems are thus excellent examples of the ‘multifunctional reactor’ concept. This chapter provides an overview of recent advances in each of these areas including fundamental and experimental aspects. Barriers and challenges confronting application of CO2-based processes in industrial catalysis, and advances in overcoming these barriers are highlighted. Keywords: supercritical; catalysis; heterogenous

A representative of the photosynthetic non-sulfur purple bacteria (Athiorhodaceae) capable of using simple alcohols has been isolated in pure culture. By means of quantitative analysis of cultures at different stages of development it has been shown that this organism converts isopropanol quantitatively into acetone, simultaneously reducing CO2 in the light. The data can be represented by the equation 2 CH3CHOHCH3 + CO2 → 2 CH3COCH3 + (CH2O) + H2O. Manometric experiments with suspensions of resting cells have fully corroborated the results obtained with growing cultures. The experiments have conclusively proved that an organic substrate may fulfill exclusively the function of hydrogen donor for the photochemical CO2-reduction in purple bacteria photosynthesis.

Many processes that use highly tunable gas-expanded liquids (GXLs) rely on the fact that CO2 addition can greatly affect the polarity of the solvent. We have examined several measures of bulk and local polarity in CO2-expanded acetonitrile to enable more effective exploitation of these polarity changes. The rate of the nucleophilic substitution reaction of tributylamine with methyl p-nitrobenzenesulfonate has been analyzed as a function of solvent composition by using in situ high-pressure UV/vis spectroscopy. We have also measured solvatochromic properties including the Kamlet-Taft pi* parameter and Kosower's Z-value. We correlate these local polarity-based kinetic and solvatochromic measures to develop a better understanding of these property changes as a function of bulk and local solvent composition. The data suggest that local composition enhancement in CO2-expanded acetonitrile has a significant impact on the reaction kinetics.

Proflavine hemisulfate, an acridine-derived fluorescent dye, can be used as a rapid stain for cytologic examination of biological specimens. Proflavine fluorescently stains cell nuclei and cytoplasmic structures, owing to its small amphipathic structure and ability to intercalate DNA. In this manuscript, we demonstrated the use of proflavine as a rapid cytologic dye on a number of specimens, including normal exfoliated oral squamous cells, cultured human oral squamous carcinoma cells, and leukocytes derived from whole blood specimens using a custom-built, portable, LED-illuminated fluorescence microscope. No incubation time was needed after suspending cells in 0.01% (w/v) proflavine diluted in saline. Images of proflavine stained oral cells had clearly visible nuclei as well as granular cytoplasm, while stained leukocytes exhibited bright nuclei, and highlighted the multilobar nature of nuclei in neutrophils. We also demonstrated the utility of quantitative analysis of digital images of proflavine stained cells, which can be used to detect significant morphological differences between different cell types. Proflavine stained oral cells have well-defined nuclei and cell membranes which allowed for quantitative analysis of nuclear to cytoplasmic ratios, as well as image texture analysis to extract quantitative image features.

Hemagglutination is a specific and sensitive technique for investigating the purity of lipoproteins and the immunologic relationships between low density lipoprotein fractions. The Sf 10–400 and Sf 3–9 lipoprotein fractions, isolated from human serum by dextran sulfate-density gradient centrifugation procedure and repurified by centrifugation appeared to contain only lipoprotein antigens since these fractions did not stimulate the production of antibodies against other serum proteins. Cross-absorption experiments with lipoproteins carried on "tanned" cells demonstrated that the Sf 3–9 lipoprotein fraction contains all the antigenic components of the Sf 10–400 lipoprotein fraction together with additional antigenic components not found in the Sf 10–400 lipoprotein fraction. Thus Sf 3–9 and Sf 10–400 lipoprotein fractions are immunologically similar but not identical. Low density lipoproteins contain no antigens in common with the high density lipoproteins. An Sf 3–9 antiserum can be used to detect both Sf 3–9 and Sf 10–400 antigens. The Sf 3–9 lipoprotein fraction used as an antigen will detect antibodies against both Sf 3–9 and Sf 10–400 lipoprotein fractions. The Sf 3–9 and Sf 10–400 antisera did not contain immune antibodies against erythrocytes of the different blood groups or against sheep, guinea pig, dog, calf, pig, horse, and chicken erythrocytes. Normal subjects and subjects with recent myocardial infarctions had no circulating autoantibodies against the Sf 3–9 and Sf 10–400 lipoprotein fractions.

SummaryHuman low density Sf 3-9 lipoproteins can be frozen and thawed, stored at —20°C, and heated to 56°C for 45 minutes without altering their immunological characteristics in precipitin ring and agar diffusion tests. Lipoprotein fractions stored at 4°C are decomposed by bacterial action. Aqueous merthiolate added to final dilution of 1:10,000 prevents bacterial contamination in lipoprotein fractions stored at 4°C without altering immunological characteristics of the lipoproteins. Freezing and thawing increases turbidity of lipoprotein solutions but does not alter lipid and protein patterns obtained with paper electrophoresis.

The administration of testosterone propionate (TP) or estradiol benzoate (EB) to the neonatal female rat induces masculinization of the hypothalamus and results in a tonic pattern of gonadotropin (GTH) secretion and the absence of ovulation. To determine the relation between this effect of steroids on the developing hypothalamus and endogenous gonadal activity, newborn rats were subjected to gonadectomy and/or steroid injection, or gonadal transplantation. The mode of GTH secretion of the host was ascertained by examining the histology of subcutaneous ovarian grafts. Corpora lutea (CL) in such grafts were considered as evidence of the cyclic release of GTH, and their absence as evidence of the tonic or masculine mode of GTH secretion. CL were found in ovarian grafts removed from females ovariectomized on day 2 or 6 of age, and from males castrated on day 2 or 3, some of which received ovarian grafts at the time of castration. CL were absent in grafts removed either from neonatally ovariectomized females g...