Search

Lasers are fundamental tools in research and development. The shape of an incident laser beam directly affects the results, when it propagates through complex structured meso‐aspheric optical elements. In conic‐based systems utilizing elements such as axicons, the impact of secondary lobes is mostly overlooked, although the intensity distributions at the central spot and the side‐lobes directly affect the beam properties. We investigate the interaction of two axicons (160° and 170°) with incident beams approximated by Gaussian, high‐order Flattened‐Gaussian, and low‐order Flattened‐Gaussian functions. We demonstrate that replacing an incident Gaussian beam with a low‐order Flattened‐Gaussian beam reduces the secondary lobes and significantly improves the uniformity of the intensity profile. We practically applied this effect in engineering a conic‐aspheric‐based static light‐sheet microscope producing markedly improved results. [ABSTRACT FROM AUTHOR]

We developed an open‐source deconvolution software that stunningly increases the visibility of minute details, as for example, neurons or nerve fibers in light‐sheet microscopy or confocal microscopy data by combining rolling ball background subtraction in three directions with deconvolution using a synthetic or measured point spread function. Via automatic block‐wise processing image stacks of virtually unlimited size can be deconvolved even on small computers with 8 or 16 GB RAM. By parallelization and optional GPU‐acceleration, the software works with high speed: On a PC equipped with a state‐of‐the‐art NVidia graphic board a three dimensional (3D)‐stack of about 1 billion voxels can be deconvolved within 5 to 10 minutes. The implemented variation of the Richardson‐Lucy deconvolution algorithm preserves the photogrammetry of the image data by using flux‐preserving regularization, an approach that to our knowledge has not been applied for deconvolving microscopy data before. [ABSTRACT FROM AUTHOR]

Objective: Autoantibodies against CD74 (anti‐CD74) are associated with ankylosing spondylitis (AS). The present multicenter study, the International Spondyloarthritis Autoantibody (InterSpA) trial, was undertaken to compare the sensitivity and specificity of anti‐CD74 and HLA–B27 in identifying patients with nonradiographic axial spondyloarthritis (axSpA). Methods: Patients ages 18–45 years with inflammatory back pain of ≤2 years' duration and a clinical suspicion of axSpA were recruited. HLA–B27 genotyping and magnetic resonance imaging of sacroiliac joints were performed in all patients. One hundred forty‐nine patients with chronic inflammatory back pain (IBP) not caused by axSpA served as controls, and additional controls included 50 AS patients and 100 blood donors whose specimens were analyzed. Results: One hundred patients with inflammatory back pain received a diagnosis of nonradiographic axSpA from the investigators and fulfilled the Assessment of SpondyloArthritis international Society (ASAS) criteria. The mean age was 29 years, and the mean symptom duration was 12.5 months. The sensitivity of IgA anti‐CD74 and IgG anti‐CD74 for identifying the 100 axSpA patients was 47% and 17%, respectively. The specificity of both IgA anti‐CD74 and IgG anti‐CD74 was 95.3%. The sensitivity of HLA–B27 was 81%. The positive likelihood ratios were 10.0 (IgA anti‐CD74), 3.6 (IgG anti‐CD74), and 8.1 (HLA–B27). Assuming a 5% pretest probability of axSpA in chronic back pain patients, the posttest probability, after consideration of the respective positive test results, was 33.3% for IgA anti‐CD74, 15.3% for IgG anti‐CD74, and 28.8% for HLA–B27. A combination of IgA anti‐CD74 and HLA–B27 results in a posttest probability of 80.2%. Conclusion: IgA anti‐CD74 may be a useful tool for identifying axSpA. The diagnostic value of the test in daily practice requires further confirmation. [ABSTRACT FROM AUTHOR]

Here, we present an optically optimized system for static ultramicroscopy imaging technique. The unit for generating an ultra‐thin light sheet employs aspheric and meso‐optical elements (meso‐aspheric system). An analytical as well as an experimental comparison between the light sheet produced by the standard system (using a rectangular slit aperture and one cylindrical lens) and the one produced by our latest optimized system, which converts a symmetrical Gaussian beam into an ultra‐thin light sheet is presented. Using the new light sheet in combination with our objective equipped with a modulator unit to compensate the refractive index mismatch between air and mediums with indices of 1.45–1.56, we present high resolution images of various biological samples that were chemically cleared using different methods. They demonstrate a marked improvement in quality, contrast and resolution. [ABSTRACT FROM AUTHOR]

Based on the modal analysis method, we developed a model that describes the output beam of a diode‐pumped solid state (DPSS) laser emitting a multimode beam. Measuring the output beam profile in the near field and at the constructed far field the individual modes, their respective contributions, and their optical parameters are determined. Using this information, the beam is optically reshaped into a quasi‐Gaussian beam by the interference and superposition of the various modes. This process is controlled by a mode modulator unit that includes different meso‐aspheric elements and a soft‐aperture. The converted beam is guided into a second optical unit comprising achromatic‐aspheric elements to produce a thin light sheet for ultramicroscopy. We found that this light sheet is markedly thinner and exhibits less side shoulders compared with a light sheet directly generated from the output of a DPSS multimode laser. [ABSTRACT FROM AUTHOR]

Moreover, Rainer is always interested in ethical and legal discussions concerning meteorites, due to the worldwide excessive regulation to integrate meteorites as cultural heritage. This has resulted in meteorite discovery reductions in the countries concerned - only the support of meteorite hunters produces the important scientific research results. Besides his scientific activities, he teaches interested people and pupils in meteoritics by evening lectures, lectures during the International Meteorite Fairs he organized, bilingual meteorite seminars, German meteorite colloquia, and field work with students and people interested in natural history. 13 Bartoschewitz R., Park J., Nagao K., Okazaki R., and Kurtz T. 2009a. Lunar meteorite SaU 300 - Noble gas record. [Extracted from the article]

We review the basics of the Effective Hamiltonian Crystal Field (EHCF) method originally targeted for calculations of the intra-shell excitations in the d-shells of coordination compounds of the first row transition metal. The formalism employs in the concerted way the McWeeny's group-function approximation and the Lowdin partition technique. It is needed for description of the transition metal complexes with partially filled d-shells where the (static) electronic correlations are manifested. These features are particularly important for electron fillings close to 'half shell' ones occurring, for example, in the Fe2+ and Fe3+ ions. Recently we extended this methodology to polynuclear coordination compounds to describe magnetic interactions of the effective spins residing in several open d-shells. This improves the accuracy from about 1000 cm−1 to that of about 100 cm−1, that is, eventually by an order of magnitude. This approach implemented in the MagAixTic package is applied here to a series of binuclear Fe(III) complexes featuring μ-oxygen superexchange pathways. The results of calculations are in a reasonable agreement with available experimental data and other theoretical studies of protonated bridges. Further we discuss the application of the EHCF to analysis of Mosbauer experiments performed on two organometallic solids: FeNCN and Fe(HNCN)2 and conjecture a new thermal effect in the latter material. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Several genotoxicity endpoints have been evaluated to define nonlinear dose-responses for SN1 and SN2 alkylating genotoxicants. Dose-response studies acknowledging the process of multistage tumorigenesis are important; however, data pertaining nonlinearity are not yet available. In this communication, the role of DNA repair in the dose-response relationship for benign papillomas was examined using the two-stage skin carcinogenesis protocol. The data obtained with O6-methylguanine-DNA methyltransferase (MGMT) overexpressing mice in which papillomas were induced by a single topical treatment with N-methyl- N-nitrosourea (MNU) followed by promotion with 12- O-tetradecanoylphorbol-13-acetate are reported. As MGMT efficiently protects cells from mutations by repairing O6-methylguanine, a miscoding lesion induced by MNU, the question whether MGMT is able to nullify carcinogenic lesions to an extent where they would be considered nonhazardous has been addressed. It is shown here that MGMT overexpression significantly protects against, but does not completely nullify, the effect of MNU in tumor initiation. The possible mechanisms involved have also been discussed. Environ. Mol. Mutagen. 55:145-150, 2014. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Using a combination of achromatic aspheric optical elements and achromatic cylindrical lenses, we developed an improved laser light sheet generator for two-side illumination ultramicroscopy. This light sheet generator has a much longer Rayleigh range, a more uniform spatial intensity distribution along x -, y - and z-axis, and reduced aberrations than the standard system consisting of a slit aperture and a single cylindrical lens, which is commonly used in light sheet microscopy. As there is no truncation of the beam by a slit aperture in our design the laser energy is used more efficiently. Applying this light sheet generator to ultramicroscopy of chemically cleared biological samples, such as Drosophila, dissected mouse hippocampi, and entire mouse brains, we achieved a markedly improved resolution of fine details. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Nanoscopic metal fluorides with surface hydroxy groups are of broad interest in heterogeneous catalysis. With both Lewis and Brønsted acid sites on the surface, these catalysts can be applied to a wide range of reactions. Having previously synthesised AlF3- and MgF2-based catalysts, we report a new transition metal fluoride with bi-acidity. A pre-dehydration procedure was developed to introduce hydroxy groups to a Lewis acid, FeF3. Subsequently, ternary nanoscopic FeF3-MgF2 with enhanced porosity was prepared through a one-step fluorination. The interaction between MgF2 and FeF3 was elucidated. Surface characterisation revealed a remarkable increase in the surface area of FeF3-MgF2 compared with FeF3. More importantly, medium-strong Lewis and Brønsted acid sites were detected on the FeF3-MgF2 surface. In line with its bi-acidity, FeF3-MgF2 was highly active in the model reaction, the isomerisation of citronellal to isopulegol. Finally, we discuss how the porosity and surface acidity jointly determine the activity of FeF3-MgF2. Our study demonstrates the feasibility of ternary FeF3-MgF2 and opens new possibilities to synthesise bi-acidic fluoride catalysts. [ABSTRACT FROM AUTHOR]

BACKGROUND Jatropha cordata and Jatropha cardiophylla are native to northwestern Mexico and are adapted to arid and semi-arid conditions (<500 mm of precipitation and temperatures from 8 to 45 °C). The aim of this study was to evaluate the chemical composition of J. cordata and J. cardiophylla kernels and oils as well as antinutrients in the defatted kernel meals of these species. RESULTS Kernels of J. cordata and J. cardiophylla seeds analysed in this study were rich in crude protein (283 and 289 g kg−1 respectively) and lipid (517 and 537 g kg−1 respectively). The main fatty acids in J. cordata and J. cardiophylla oils were linoleic and oleic acids. High levels of trypsin inhibitor and phytates and low levels of saponins were present in the meals. The phorbol ester contents in J. cordata and J. cardiophylla kernel meals were 2.73 and 1.46 mg g−1 respectively. CONCLUSION For both J. cordata and J. cardiophylla it could be inferred that (a) the oil and kernel meal were toxic and the kernel meal could be used as livestock feed only after detoxification, (b) the oil could be used for non-alimentary purposes, i.e. biodiesel production, and (c) the seed or oil could be used for isolating various bioactive compounds for pharmaceutical and agricultural applications. © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Human embryonic stem cells (hESCs) and induced pluripotent stem cells proliferate rapidly and divide symmetrically producing equivalent progeny cells. In contrast, lineage committed cells acquire an extended symmetrical cell cycle. Self-renewal of tissue-specific stem cells is sustained by asymmetric cell division where one progeny cell remains a progenitor while the partner progeny cell exits the cell cycle and differentiates. There are three principal contexts for considering the operation and regulation of the pluripotent cell cycle: temporal, regulatory, and structural. The primary temporal context that the pluripotent self-renewal cell cycle of hESCs is a short G1 period without reducing periods of time allocated to S phase, G2, and mitosis. The rules that govern proliferation in hESCs remain to be comprehensively established. However, several lines of evidence suggest a key role for the naïve transcriptome of hESCs, which is competent to stringently regulate the embryonic stem cell (ESC) cell cycle. This supports the requirements of pluripotent cells to self-propagate while suppressing expression of genes that confer lineage commitment and/or tissue specificity. However, for the first time, we consider unique dimensions to the architectural organization and assembly of regulatory machinery for gene expression in nuclear microenviornments that define parameters of pluripotency. From both fundamental biological and clinical perspectives, understanding control of the abbreviated ESC cycle can provide options to coordinate control of proliferation versus differentiation. Wound healing, tissue engineering, and cell-based therapy to mitigate developmental aberrations illustrate applications that benefit from knowledge of the biology of the pluripotent cell cycle. J. Cell. Physiol. 228: 9-20, 2013. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

High surface ozone concentrations are recognized as an emerging threat to food security in Asia. This study aimed at determining the effects of ozone on the nutritive quality of rice straw, a by-product of rice grain production and a major feed resource for ruminant livestock. Further, the question was addressed whether negative effects of ozone can be mitigated through molecular breeding. Rice plants from three different genotypes were exposed to four different ozone treatments in fumigation chambers from transplanting to maturity. These genotypes were (i) IR64, one of the most wide spread indica varieties in the world, (ii) Nipponbare, a typical japonica variety, and (iii) SL41, an ozone tolerant breeding line that carried chromosomal inserts at the ozone tolerance QTL OzT9 in the genetic background of Nipponbare. The treatments consisted of (i) charcoal filtered air, (ii) simulated ambient ozone concentration, (iii) 2 × ambient ozone concentration, and (iv) 2.5 × ambient ozone concentration. The effects of ozone on the chemical composition of straw were clearly dependent of the ozone level, and were significant even at ambient ozone concentration. Increases in crude ash, lignin and phenolics concentration adversely affected the digestibility as demonstrated in incubation experiments simulating rumen digestion in vitro. Negative ozone effects included reductions in the rate and extent of gas production due to inhibition of microbial fermentation, reduced formation of short chain fatty acids (SCFA), and a decrease in the true organic matter digestibility. The ozone tolerant genotype SL41 was less responsive to ozone than its more susceptible recurrent parent Nipponbare in terms of lignin and phenolics formation, organic matter digestibility and SCFA production. These data demonstrate that the feed quality of rice straw is affected by ozone even at ambient concentration, and that these negative effects are mitigated by the ozone tolerance QTL OzT9. [ABSTRACT FROM AUTHOR]

Terpenes are the largest group of phytochemicals that exhibit diverse functions in mediating antagonistic and beneficial interactions in, and among, organisms. For many years the abundance and distribution of terpenoid compounds in plants have benefitted both nature and human civilization. Jatropha species, belonging to the family Euphorbiaceae, are a rich source of terpenoid compounds. Among the terpenes, diterpenoid compounds have dominated the research area in Jatropha species with respect to their novel chemical structures and medicinal values. The present review describes the chemistry and biological activities of an array of Jatropha diterpenes. The diterpenes isolated from Jatropha species belongs to rhamnofolane, daphnane, lathyrane, tigliane, dinorditerpene, deoxy preussomerin and pimarane skeletal structures. Among the 68 diterpenes collated in this review, the biological activity of compounds varied distinctly-the majority of the diterpenes exhibited cytotoxic, antitumor and antimicrobial activities in vitro. To name a few, jatrophone, spruceanol and jatrophatrione exhibited antitumor properties against P338 lymphocytic leukemia and japodagrol against KB carcinoma cells. Whereas, curcusone B exhibited anti-invasive effects against cholangiocarcinoma cells. The phorbol esters ( Jatropha factor C1- C6) and Jatropherol exhibited insect deterrent/cytotoxic properties. Many diterpenes (jatrophalactam, faveline derivatives, multifolone, curcusone, jatrophone derivatives etc.) showed in-vitro cytotoxic activity, while japodagrin, jatrogrossidione derivatives and jatropholone derivatives exhibited antimicrobial activities. Jatropha diterpenoids having a wide spectrum of bioactivity could form lead compounds or could be used as templates for the synthesis of new compounds with better biological activity for utilization in the pharmaceutical industries. [ABSTRACT FROM AUTHOR]

In the majority of implementations of light sheet microscopy, such as ultramicroscopy, the laser beam illuminating the specimen is truncated by a slit aperture before it is focused to a light sheet by a single cylindrical lens. A light sheet generated in this way can be made very thin near to the focal point, but unfortunately its Rayleigh range is severely limited. This problem can be partially solved by using a smaller slit aperture. However, this also causes a major loss in power, a severe broadening of the beam waist, and thus a significant loss of resolution along the detection axis. We developed improved light-sheet-generation optics, which provide longer Raleigh ranges, whilst retaining beam waists comparable to our standard system with one cylindrical lens. Using the modified system we achieved a marked improvement in the resolution of ultramicroscopy reconstructions of representative biological specimens. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Jatropha curcas seeds are rich in oil (28–32%), which can be converted to high quality biodiesel. The oil is non-edible due to the presence of toxic compounds, namely, phorbol esters (PEs). PEs have a number of agricultural/medicinal/pharmaceutical applications and hence their recovery generates a value added co-product towards the biodiesel production chain. This study aims to assess the effects of PE extraction on quality of both the residual oil and the biodiesel production from it. Two Approaches (1, use of an Ultra-turrax; and 2, use of a magnetic stirrer) were used with an effective treatment time of 2 and 5 min, resulting in 80 and 78% extraction of PEs, respectively. The phosphorus content was reduced by 70.2 and 75.8%, free fatty acids by 55.3 and 55.6%, and the fatty acid composition did not change in the residual oils. The peroxide value increased from 2.69 (untreated oil) to 3.01 and 3.49 mequiv O2/kg in the residual oils following Approach 1 and Approach 2, respectively. The biodiesel prepared from both residual oils met European (EN 14214:2008) and American biodiesel standard (ASTM D6751-09) specifications. Oxidative stability indices for both the biodiesels were well within the permitted limit. It is concluded that PEs could be isolated in active forms for various applications by either of the two methods with a high yield and the residual oil can be processed to produce high quality biodiesel. [ABSTRACT FROM AUTHOR]

Self-renewal of pluripotent human embryonic stem (hES) cells utilizes an abbreviated cell cycle that bypasses E2F/pRB-dependent growth control. We investigated whether self-renewal is alternatively regulated by cyclin/CDK phosphorylation of the p220NPAT/HiNF-P complex to activate histone gene expression at the G1/S phase transition. We show that cyclin D2 is prominently expressed in pluripotent hES cells, but cyclin D1 eclipses cyclin D2 during differentiation. Depletion of cyclin D2 or p220NPAT causes a cell cycle defect in G1 reflected by diminished phosphorylation of p220NPAT, decreased cell cycle dependent histone H4 expression and reduced S phase progression. Thus, cyclin D2 and p220NPAT are principal cell cycle regulators that determine competency for self-renewal in pluripotent hES cells. While pRB/E2F checkpoint control is relinquished in human ES cells, fidelity of physiological regulation is secured by cyclin D2 dependent activation of the p220NPAT/HiNF-P mechanism that may explain perpetual proliferation of hES cells without transformation or tumorigenesis. J. Cell. Physiol. 222: 456–464, 2010. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Self-renewal of human embryonic stem (hES) cells proceeds by a unique abbreviated cell cycle with a shortened G1 phase and distinctions in molecular cell cycle regulatory parameters. In this study, we show that early lineage-commitment of pluripotent hES cells modifies cell cycle kinetics. Human ES cells acquire a lengthened G1 within 72 h after lineage-programming is initiated, as reflected by loss of the pluripotency factor Oct4 and alterations in nuclear morphology. In hES cells that maintain the pristine pluripotent state, we find that autocrine mechanisms contribute to sustaining the abbreviated cell cycle. Our data show that naïve and mitotically synchronized pluripotent hES cells are competent to initiate two consecutive S phases in the absence of external growth factors. We conclude that short-term self-renewal of pluripotent hES cells occurs autonomously, in part due to secreted factors, and that pluripotency is functionally linked to the abbreviated hES cell cycle. J. Cell. Physiol. 222:103–110, 2010. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Phorbol esters present in Jatropha curcas oil are toxic when consumed and are co-carcinogens. These could be a potential constraint in the widespread acceptance of Jatropha oil as a source of biodiesel. Phorbol esters were quantified in the fractions obtained at different stages of oil pre-treatment and biodiesel production. During degumming some phorbol esters were removed in the acid gums and wash water. This implies that the use of these acid gums in animal feed is not possible and care should be taken when disposing the wash water into the environment. Silica treatment did not decrease the phorbol esters, while stripping/deodorization at 260 °C at 3 mbar pressure with 1% steam injection completely degraded phorbol esters. Phorbol esters were not detected in stripped oil, fatty acid distillate, transesterified oil (biodiesel) and glycerine. The presence of possibly toxic phorbol ester degradation products in these fractions could not be ruled out. [ABSTRACT FROM AUTHOR]

The clinical and research value of human embryonic stem cells (hESC) depends upon maintaining their epigenetically naïve, fully undifferentiated state. Inactivation of one X chromosome in each cell of mammalian female embryos is a paradigm for one of the earliest steps in cell specialization through formation of facultative heterochromatin. Mouse ES cells are derived from the inner cell mass (ICM) of blastocyst stage embryos prior to X-inactivation, and cultured murine ES cells initiate this process only upon differentiation. Less is known about human X-inactivation during early development. To identify a human ES cell model for X-inactivation and study differences in the epigenetic state of hESC lines, we investigated X-inactivation in all growth competent, karyotypically normal, NIH approved, female hESC lines and several sublines. In the vast majority of undifferentiated cultures of nine lines examined, essentially all cells exhibit hallmarks of X-inactivation. However, subcultures of any hESC line can vary in X-inactivation status, comprising distinct sublines. Importantly, we identified rare sublines that have not yet inactivated Xi and retain competence to undergo X-inactivation upon differentiation. Other sublines exhibit defects in counting or maintenance of XIST expression on Xi. The few hESC sublines identified that have not yet inactivated Xi may reflect the earlier epigenetic state of the human ICM and represent the most promising source of NIH hESC for study of human X-inactivation. The many epigenetic anomalies seen indicate that maintenance of fully unspecialized cells, which have not formed Xi facultative heterochromatin, is a delicate epigenetic balance difficult to maintain in culture. J. Cell. Physiol. 216: 445–452, 2008. © 2008 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Human embryonic stem (ES) cells have an expedited cell cycle (∼15 h) due to an abbreviated G1 phase (∼2.5 h) relative to somatic cells. One principal regulatory event during cell cycle progression is the G1/S phase induction of histone biosynthesis to package newly replicated DNA. In somatic cells, histone H4 gene expression is controlled by CDK2 phosphorylation of p220NPAT and localization of HiNF-P/p220NPAT complexes with histone genes at Cajal body related subnuclear foci. Here we show that this ‘S point’ pathway is operative in situ in human ES cells (H9 cells; NIH-designated WA09). Immunofluorescence microscopy shows an increase in p220NPAT foci in G1 reflecting the assembly of histone gene regulatory complexes in situ. In contrast to somatic cells where duplication of p220NPAT foci is evident in S phase, the increase in the number of p220NPAT foci in ES cells appears to precede the onset of DNA synthesis as measured by BrdU incorporation. Phosphorylation of p220NPAT at CDK dependent epitopes is most pronounced in S phase when cells exhibit elevated levels of cyclins E and A. Our data indicate that subnuclear organization of the HiNF-P/p220NPAT pathway is rapidly established as ES cells emerge from mitosis and that p220NPAT is subsequently phosphorylated in situ. Our findings establish that the HiNF-P/p220NPAT gene regulatory pathway operates in a cell cycle dependent microenvironment that supports expression of DNA replication-linked histone genes and chromatin assembly to accommodate human stem cell self-renewal. J. Cell. Physiol. 213: 9–17, 2007. © 2007 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Rapid self-renewal of human embryonic stem (ES) cells (NIH designation WA01 and WA09) is accommodated by an abbreviated cell cycle due to a reduction in the G1 phase. Thus, molecular mechanisms operative in ES cells may expedite the cellular commitment to progress into S phase to initiate replication of DNA and biosynthesis of histone proteins to form new chromatin. Here we show that the selective cell cycle regulated expression of individual histone H4 gene copies, which is typical for somatic cell types, is already firmly established in human ES cells. This early establishment of H4 gene regulation, which is E2F independent, is consistent with co-expression of the cognate transcriptional regulators HiNF-P and p220NPAT. Human ES cells differ from somatic cells in the expression of members of the E2F family and RB-related pocket proteins (p105RB1, p107RBL1, and p130RBL2/RB2) that control expression of genes encoding enzymes for nucleotide metabolism and DNA synthesis. Human ES cells rapidly and robustly (>200-fold) induce the cyclin dependent kinase (CDK) inhibitor p21WAF1/CIP1 upon gamma-irradiation. This DNA damage response promptly reduces histone gene expression as well as mRNA levels for HiNF-P and p220NPAT and causes accumulation of unprocessed histone H4 precursor RNAs. Furthermore, while E2F4, E2F5 and p130RBL2/RB2 are the major E2F and pocket protein mRNAs in actively proliferating ES cells, expression levels of E2F5, E2F6, and p105RB1 are most strongly elevated during cell cycle arrest in cells responding to DNA damage. Our data suggest that the brief G1 phase of ES cells is supported by a potent p21WAF1/CIP1 related DNA damage response that functions through several mechanisms to rapidly inhibit cell cycle progression. This response may alter the E2F/pocket protein combinations that control E2F dependent genes and block H4 gene expression by inhibiting histone-specific transcription factors and processing of histone gene transcripts, as well as by destabilizing histone mRNAs. J. Cell. Physiol. 210: 517–526, 2007. © 2006 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Competency for self-renewal of human embryonic stem (ES) cells is linked to pluripotency. However, there is a critical paucity of fundamental parameters of human ES cell division. In this study we show that human ES cells (H1 and H9; NIH-designated WA01 and WA09) rapidly proliferate due to a very short overall cell cycle (15–16 h) compared to somatic cells (e.g., normal diploid IMR90 fibroblasts and NT-2 teratocarcinoma cells). The human ES cell cycle maintains the four canonical cell cycle stages G1, S, G2, and M, but the duration of G1 is dramatically shortened. Bromodeoxyuridine (BrdU) incorporation and FACS analysis demonstrated that 65% of asynchronously growing human ES cells are in S phase. Immunofluorescence microscopy studies detecting BrdU labeled mitotic chromosomes, Ki67 domains, and p220NPAT containing Cajal bodies revealed that the durations of the S (∼8 h), G2 (∼4 h), and M phases (∼1 h) are similar in ES and somatic cells. We determined that human ES cells remain viable after synchronization with either nocodazole or the anti-tumor drug Paclitaxel (taxol) and have an abbreviated G1 phase of only 2.5–3 h that is significantly shorter than in somatic cells. Molecular analyses using quantitative RT-PCR demonstrate that human ES cells and somatic cells express similar cell cycle markers. However, among cyclins and cyclin-dependent kinases (CDKs), we observed high mRNA levels for the G1-related CDK4 and cyclin D2 genes. We conclude that human ES cells exhibit unique G1 cell cycle kinetics and use CDK4/cyclin D2 related mechanisms to attain competency for DNA replication. J. Cell. Physiol. 209: 883–893, 2006. © 2006 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Lysozyme and amylase are the most abundant enzymatic components in the salivary pellicle. The purpose of the present study was to determine the influence of different substrata on amylase and lysozyme activity in salivary pellicles formed in situ. Slabs (5 mm diameter) of bovine dentine and enamel, of titanium, gold alloy, resin composite, PMMA, amalgam, and feldspar ceramic were fixed on the buccal sites of individual splints worn by six subjects for 30 min to allow pellicle formation. Thereafter, slabs were removed from the trays and rinsed with running water. Lysozyme activity was determined via lysis of Micrococcus lysodeicticus. Amylase activity was measured with a photometric method using 2‐chloro‐4‐nitrophenyl‐4‐O‐β‐D‐galactopyranosylmaltotriosid (GalG2CNP) as substrate. Both pellicle enzymes were evaluated in the immobilized as well as in the desorbed state. Salivary enzyme activities were also measured. All investigated pellicles exhibited lysozyme and amylase activity. Great intraindividual and interindividual differences were observed. Over all samples, immobilized amylase activity amounted to 0.65 ± 0.64 mU/cm2. Immobilized lysozyme activity was 5.04 ± 1.55 U/cm2. There were no major effects of the substratum on pellicle‐bound amylase and lysozyme activity. Immobilized and desorbed enzyme activities revealed a strong correlation (lysozyme: r = 0.700; amylase: r = 0.990). Salivary enzyme activities had only little impact on pellicle‐bound enzyme activities. Amylase and lysozyme are incorporated in the acquired in situ pellicle on different solid surfaces in an active conformation. Dental material and enzyme activity in the saliva have only little impact on enzymatic activity in the pellicle in situ. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2006 [ABSTRACT FROM AUTHOR]

Aggressive conflicts between males are often resolved by means of multiple ritualized agonistic displays without damaging escalation. Apparently, in such cases by using those displays opponents exchange important motivational and physical information on which they base a decision to stay or leave the interaction. In the Siamese fighting fish, the time spent spreading the dorsal fin and erecting the gill coverts predicts who will be the winner or loser of the interaction. Two experiments were carried out to study whether display performance might be costly. First, oxygen consumption was measured during mirror-image stimulation. This experiment showed that oxygen consumption was positively correlated with gill cover erection and dorsal fin spread. In the second experiment, a fight between two opponents was simulated and the oxygen consumption of the expected winner and loser was compared. Metabolic rates were not different between winners and losers before and during the fight, but winners showed higher oxygen consumption in the night after the fight. These results are in accordance with costs of display performance and with long-lasting physiological consequences of winning or losing a fight. Aggr. Behav. 32:1–7, 2006. © 2006 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

Rice is a key component in global food security, as it is the main ingredient in the daily diets of around 3 billion people, especially in Asia. Like all agricultural production, rice cultivation depends on scarce natural resources. This article briefly outlines the utilization of land and water in rice production, and suggests an approach for optimizing use efficiency, namely through the combination of rice and fish culture. The authors argue that the utilization of land and fresh water is optimized through integrated and complementary production of rice and fish— two basic foods items in daily local diets. The article reviews currently available scientific literature on integrated rice-fish systems. Rice-fish culture systems are briefly characterized, and respective yield potential and interactions between rice and fish are discussed. Results of socio-economic surveys regarding the adoption of integrated rice-fish culture are summarized. The article also reviews literature on the impact of fish culture on rice field ecology as outlined in studies on weed infestation, insect populations, and greenhouse gas emissions. The article concludes that rice-fish culture can be an option to help rice producing countries keep pace with soaring domestic demand for food, especially fish. Integrated rice and fish culture optimizes the benefits of scarce land and water resources through complementary use, and exploits the synergies between fish and plant. [ABSTRACT FROM AUTHOR]

The concept of substituting bio-diesel produced from plantations on eroded soils for conventional diesel fuel has gained wide-spread attention in India. In recent months, the Indian central Government as well as some state governments have expressed their support for bringing marginal lands, which cannot be used for food production, under cultivation for this purpose.Jatropha curcasis a well established plant in India. It produces oil-rich seeds, is known to thrive on eroded lands, and to require only limited amounts of water, nutrients and capital inputs. This plant offers the option both to cultivate wastelands and to produce vegetable oil suitable for conversion to bio-diesel. More versatile than hydrogen and new propulsion systems such as fuel cell technology, bio-diesel can be used in today's vehicle fleets worldwide and may also offer a viable path to sustainable transportation, i.e., lower greenhouse gas emissions and enhanced mobility, even in remote areas. Mitigation of global warming and the creation of new regional employment opportunities can be important cornerstones of any forward looking transportation system for emerging economies. [ABSTRACT FROM AUTHOR]

Background: Chronic alcohol ingestion leads to endoto-emia which is believed to play an important role in the pathogenesis of alcoholic liver disease (ALD). The purpose of this study was to determine if chronic ethanol consumption, in addition to affecting plasma endoto-in and cytokines, also affects the endoto-in-neutralizing capacity (ENC), sCD14, and sICAM-1, in patients with ALD. A second aim was to identify correlations between these latter parameters, endoto-in, and cytokines, especially IL-10. Methods: Hospitalized patients with various degrees of ALD ( n= 59), and 20 healthy volunteers were studied. Plasma endotoxin and ENC were determined using our kinetic Limulus amebocyte lysate test. Cytokines, sCD14, and sICAM-1 were measured by enzyme-linked immunosorbent assay. Results: Patients with ALD e-hibited a mild endoto-emia ( p < 0.01) and a marked decrease in ENC ( p < 0.0002). TNF-α ( p < 0.05), IL-6 ( p < 0.0001), sICAM ( p < 0.005), and sCD14 ( p < 0.0005) were significantly elevated in all patients with ALD, and IL-10 ( p < 0.05) in patients with cirrhotic ALD. With the exception of IL-10, the cytokines correlated with each other and with sICAM-1. No correlations occurred between endotoxin, ENC, and sCD14, and between these and the cytokines and sICAM-1. Elevated levels of endotoxin correlate with acute excessive alcohol ingestion. No gender differences were observed. Conclusions: Acute alcohol into-ication rather than severe ALD results in significant endoto-emia. The limited capacity of plasma to neutralize endoto-in in liver injury seems to be an important factor in ALD which may be responsible for the release of endoto-in-induced mediators, such as cytokines, as well as s-ICAM-1, that are relevant in the pathogenesis of ALD. [ABSTRACT FROM AUTHOR]