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Carbohydrate-binding modules (CBMs) are protein domains located within a carbohydrate-active enzyme, with a discrete fold that can be separated from the catalytic domain. Starch-binding domains (SBDs) are CBMs that are usually found at the C-terminus in many amylolytic enzymes. The SBD from Aspergillus niger B1 (CMI CC 324262) was cloned and expressed in Escherichia coli as an independent domain and the recombinant protein was purified on starch. The A. niger B1 SBD was found to be similar to SBD from A. kawachii, A. niger var. awamori and A. shirusami (95–96% identity) and was classified as a member of the CBM family 20. Characterization of SBD binding to starch indicated that it is essentially irreversible and that its affinity to cationic or anionic starch, as well as to potato or corn starch, does not differ significantly. These observations indicate that the fundamental binding area on these starches is essentially the same. Natural and chemically modified starches are among the most useful biopolymers employed in the industry. Our study demonstrates that SBD binds effectively to both anionic and cationic starch.

The authors introduce a wave frame model and define the covariance of vector angular frame model (CVAE) in this frame. A lower bound is derived on the CVAE for source direction and orientation estimation. An explicit expression for the CVAE matrix bound is found to be diagonal, easy to interpret, and having only intrinsic singularities. A relationship is also provided between the CVAE and the mean-square angular error quality measure. >

An approach is proposed for localization of acoustic sources using an array of sensors for which the measurement of each sensor is a vector consisting of the acoustic pressure and acoustic particle velocity. A compact expression is derived for the Cramer-Rao bound (CRB) on the estimation errors of the source direction-of-arrival (DOA) parameters in the multi-source multi-vector sensor model. An explicit expression is found for the mean-square angular error bound for source localization with a single vector sensor. Two simple algorithms for estimating the source DOA with this sensor are presented along with their statistical performance analysis. >

Genomic imprinting is traditionally defined as an epigenetic process leading to parental origin-dependent monoallelic expression of some genes. The current paradigm considers this unusual expression mode as the biological raison d être of imprinting. The present chapter proposes a critical review of our ideas about genomic imprinting in light of more recent investigatory progress. Many observations are difficult to explain on the basis of the current paradigm. Studies of allelic expression of many imprinted genes and other characteristics of chromatin domains containing clustered imprinted genes, such as replication and chromatin structure, revealed an unexpectedly complex situation that challenged the role of genomic imprinting as a mechanism of transcriptional regulation. The emerging picture is that parental imprinting is a feature of large chromatin domains with their own domain-wide characteristics. The primary biological function of imprinting may reside in the differential chromatin structure of the parental chromosomal regions and not in the monoallelic expression of some of the genes contained within them.

Genomic imprinting is traditionally defined as an epigenetic process leading to parental origin-dependent monoallelic expression of some genes. The current paradigm considers this unusual expression mode as the biological raison detre of imprinting. The present chapter proposes a critical review of our ideas about genomic imprinting in light of more recent investigatory progress. Many observations are difficult to explain on the basis of the current paradigm. Studies of allelic expression of many imprinted genes and other characteristics of chromatin domains containing clustered imprinted genes, such as replication and chromatin structure, revealed an unexpectedly complex situation that challenged the role of genomic imprinting as a mechanism of transcriptional regulation. The emerging picture is that parental imprinting is a feature of large chromatin domains with their own domain-wide characteristics. The primary biological function of imprinting may reside in the differential chromatin structure of the parental chromosomal regions and not in the monoallelic expression of some of the genes contained within them.

Develops methods for localizing particle sources using detector arrays. Projection-based arrays are used and general convex, cubical, and spherical surfaces are investigated. Lower bounds are computed on the mean-square angular error (MSAE) for these arrays. The authors propose an algorithm for direction finding with the cubical array and analyze its MSAE. Potential applications of the proposed methods include finding radiation sources, localizing weak light sources, studying the environment, and verifying compliance of nuclear nonproliferation treaties. >

A novel approach is presented for the localization of electromagnetic sources using vector sensors. Two types of source transmissions are considered: (1) single signal transmission and (2) dual signal transmission. The model is given in terms of several parameters including the wave direction of arrival and state of polarization. A compact expression is derived for the Cramer-Rao bound (CRB) on the estimation errors of these parameters for the multi-source multi-vector sensor model. The advantage of using vector sensors is highlighted by explicit evaluation of the CRB and the associated mean-square angular error for source localization with a single vector sensor. A simple algorithm is proposed for estimating the source DOA with this sensor. >

Parental-specific epigenetic modifications are imprinted on a subset of genes in the mammalian genome during germ cell maturation. However, the precise timing of their establishment remains to be determined. Methylation of CpG dinucleotides has been shown to be a part of the parental imprint. We have examined how the methylation pattern characteristic of the paternal allele in germ cells are established during human spermatogenesis. Two representative imprinted genes, H19 and MEST/PEG1, were studied. The experiments were performed using the bisulphite sequencing method on microdissected individual cells at different stages of male germ cell differentiation. We show that both genes are unmethylated in fetal spermatogonia, suggesting that all pre-existing methylation imprints are already erased by this stage. The MEST/PEG1 gene remains unmethylated at all subsequent post-pubertal stages of spermatogenesis, including mature spermatozoa. The methylation of H19 typical of the paternal allele first appears in a subset of adult spermatogonia and then is maintained in spermatocytes, spermatids and mature spermatozoa. Our results suggest that the methylation imprint inherited from the parents is first erased in the male germ line at an early fetal stage. The paternal-specific imprint is re-established only later, during spermatogonial differentiation in the adult testis.

Little is known of how the genetic background effects the phenomenon of genomic imprinting. The H19 gene belongs to a cluster of imprinted genes on human chromosome 11. Here we show that the alternative splicing of a human H19 transcript is genotype-specific. Moreover, this variant transcript, which lacks exon 4, is either not found at all, is widely expressed or is confined to extra-villous cytotrophoblasts in first trimester placenta, depending on a combination of the genotype and the sex of the transmitting parent.

Primary carcinoma of the fallopian tube is rarely diagnosed preoperatively. We report the case of a 42-year-old woman with primary tubal carcinoma, which was diagnosed preoperatively on the basis of an elevated CA-125 and characteristic features on transvaginal sonography.

Homologous chromosome pairing is known to be an essential point in the meiotic process, because it allows interchromosomal exchanges (crossovers) to occur in a balanced way. Interactions between homologous loci has been shown to occur in somatic cells of plants and animals. In general, somatic pairing is less extensive than in the germ cells. Although their functional significance remains unclear, recent observations show that homologous interactions are more widespread than previously thought. It has also become apparent that imprinted chromosomal regions can be involved in homologous pairing in mammalian somatic cells. This chapter will focus on the description of long-range homologous interactions and their implications in the conrext of imprinted chromosomal regions.

The authors analyze the statistical performance of two algorithms proposed earlier (1991) for source direction estimation using a single (lumped) acoustic vector sensor. The first algorithm uses the four-dimensional acoustic pressure-velocity vector, and the second uses only the three-dimensional acoustic velocity vector. The mean-square angular errors (MSAEs) of these algorithms are evaluated and compared with their lower bound. >

Cell differentiation is traditionally seen as a sequence of genetically predetermined gene expression changes. This view has been challenged recently by the discovery of important stochastic fluctuations in gene expression and by the identification of the role these fluctuations may play in the cell fate decision. In particularly, it has been proposed that fully multipotent cells fluctuate slowly between states with varying likelihoods of differentiation and this spontaneous heterogeneity or “noise” is the central driving force behind multipotency. It has been proposed that the different phenotypic states correspond to attractor states in the “epigenetic landscape” defined by the network of genes. In our study we used myoblasts that express the differentiation marker CD56 considered as a sign of definitive fate commitment to the muscle pathway. We show experimentally that these cells fluctuate between two phenotypes. Using spatial distribution analysis of the cells in growing population, computer simulations of these observations and experimental test of the new predictions made by the model we show that the fluctuations follow a bistable dynamics driven by a microenvironment and phenotype dependent noise. We show that fluctuation between phenotypes is not a distinguishing feature of multipotent cells. Committed tissue cells (myoblasts, used in our study) also may fluctuate between different phenotypes. We suggest that phenotypic fluctuations are a general feature of any non-terminally differentiated cell, thus, reversion to a previous differentiation state is a normal event. The cellular microenvironment contributes actively to the fluctuations by increasing the noise level in cells with a given phenotype and decreasing it in others. Importantly, the microenvironment is created by the cells themselves as a consequence of their motility that creates random cell interactions. In this way each cell contributes to put together its own microenvironment that in turn stimulates it to fluctuate between the phenotypes until the most appropriate phenotypic state with low noise is found. This means that the attractor state is not cell intrinsic; rather it is specified by the joint action of the cell-intrinsic gene network and the network of cell-cell interactions. Both networks are subject to stochastic fluctuations.

The importance of honey bees to the world economy far surpasses their contribution in terms of honey production; they are responsible for up to 30% of the world's food production through pollination of crops. Since fall 2006, honey bees in the U.S. have faced a serious population decline, due in part to a phenomenon called Colony Collapse Disorder (CCD), which is a disease syndrome that is likely caused by several factors. Data from an initial study in which investigators compared pathogens in honey bees affected by CCD suggested a putative role for Israeli Acute Paralysis Virus, IAPV. This is a single stranded RNA virus with no DNA stage placed taxonomically within the family Dicistroviridae. Although subsequent studies have failed to find IAPV in all CCD diagnosed colonies, IAPV has been shown to cause honey bee mortality. RNA interference technology (RNAi) has been used successfully to silence endogenous insect (including honey bee) genes both by injection and feeding. Moreover, RNAi was shown to prevent bees from succumbing to infection from IAPV under laboratory conditions. In the current study IAPV specific homologous dsRNA was used in the field, under natural beekeeping conditions in order to prevent mortality and improve the overall health of bees infected with IAPV. This controlled study included a total of 160 honey bee hives in two discrete climates, seasons and geographical locations (Florida and Pennsylvania). To our knowledge, this is the first successful large-scale real world use of RNAi for disease control., Author Summary High rates of honey bee mortality continue to threaten food security and apicultural industries worldwide. At least some of these losses are likely the result of viral infections. Application of RNAi technologies in the treatment and management of disease promises new solutions to disease problems through the naturally occurring biological processes of living organisms. This study applied a novel dsRNA product developed specifically with the aim of improving honey bee health. The results demonstrate the successful application of RNAi strategies to improve disease tolerance. Honey bees were fed a dsRNA product, Remebee-I, in the presence of the Israeli Acute Paralysis Virus. Treatment resulted in larger colony populations and thus increased honey production. We show that IAPV specific homologous dsRNA successfully curbed the negative effects of IAPV infection in 160 honey bee hives in two discrete climates, seasons and geographical locations (Florida and Pennsylvania). We provide the first successful demonstration of the use of RNAi as a preventative treatment for an insect disease on such a large scale.

Gene therapy is a promising strategy to treat certain inherited disorders. In that context, lentiviral vectors (LV) have been used in ex vivo protocols for the stable gene-modification of hematopoietic stem cells. There are concerns about the potential genotoxicity of integrative vectors such as LV. So far, these concerns have only been envisioned as resulting from unwanted genomic insertion leading to insertional mutagenesis. At present, there has been no investigation of potential epigenetic modification induced by the procedure of gene transfer into stem cells. Epigenetic changes are known to be induced in cells following culture and stress. This prompted us to investigate if the procedure used for ex vivo lentiviral transduction which involves a period of cytokine pre-activation prior to LV infection, could induce epigenetic alterations in human CD34+ haematopoietic/progenitor cells. The expression of a panel of known epigenetic proteins was explored by immunohistochemical analysis at initiation of the treatment, post-stimulation and post-infection of umbilical cord blood CD34+ cells. To measure the patterns and levels of expression of these proteins in the cell population and to account for the heterogeneity of the CD34+ cell population, we used high throughput image analysis with the Cell Profiler Software. As expected, the cytokine pre-activation of the cells led to a heterogeneous up regulation of several proteins known to be involved in metabolic changes and stress response. Importantly, the systematic analysis of up to 30 morphological features per cell indicated that lentiviral infection itself had a distinct effect than those of cytokines. Cells infected with the LV displayed significantly different and more heterogenous phenotypic profiles compared to non-transduced cells or pre-activated only cells. These constitute the first observations to our knowledge that ex vivo lentiviral transduction of hematopoietic cells may induce epigenetic changes. Our data suggest that lentiviral transduction may represent a stress for the cell leading to an “epigenetic storm” which could induce variable deregulation of certain genes in the cells. We show that these effects could be monitored and further experiments are ongoing to evaluate the impact of different experimental conditions on such epigenetic changes.

Pregnancy is an unusual event in patients with chronic renal failure undergoing dialysis. The outcome in these cases is usually poor. We report a pregnancy complicated by severe renal insufficiency that was managed successfully by continuous ambulatory peritoneal dialysis. Dialysis was initiated at 24 weeks' gestation. At 34 weeks, premature labor associated with peritonitis resulted in the spontaneous delivery of a healthy male infant weighing 2400 g. The use of continuous ambulatory peritoneal dialysis during pregnancy offers theoretical advantages compared with hemodialysis. Our case, added to the available limited experience with this new modality, suggests that it may be an appropriate approach in women developing renal disease for the first time during pregnancy.