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PURPOSE To learn how the highest-performing primary care practices manage change when implementing improvements to diabetes care delivery. METHODS We ranked a total of 330 primary care practices submitting practice management assessments and diabetes reports to the Understanding Infrastructure Transformation Effects on Diabetes study in 2017 and 2019 by Optimal Diabetes Care performance. We ranked practices from the top quartile by greatest annual improvement to capture dynamic change. Starting with the top performers, we interviewed practice leaders to identify their most effective strategies for managing change. Interview transcripts were qualitatively analyzed to identify change management strategies. Saturation occurred when no new strategies were identified over 2 consecutive interviews. RESULTS Ten of the top 13 practices agreed to interviews. We identified 199 key comments representing 48 key care management concepts. We also categorized concepts into 6 care management themes and 37 strategic approaches. We categorized strategic approaches into 13 distinct change management strategies. The most common strategies identified were (1) standardizing the care process, (2) performance awareness, (3) enhancing care teams, (4) health care organization participation, (5) improving reporting systems, (6) engaging staff and clinicians, (7) accountability for tasks, (8) engaging leadership, and (9) tracking change. Care management themes identified by most practices included proactive care, improving patient relationships, and previsit planning. CONCLUSIONS Top-performing primary care practices identify a similar group of strategies as important for managing change during quality improvement activities. Practices involved in diabetes improvement activities, and perhaps other chronic conditions, should consider adopting these change management strategies. Key words: quality of health care; quality of health care; diabetes mellitus, type 2; delivery of health care; primary health care; organizational culture, INTRODUCTION Although the need to improve diabetes outcomes in primary care is evident, exactly how a practice successfully manages change in care delivery in l the midst of a busy [...]

PURPOSE To learn whether the COVID-19 pandemic's disruptions and associated reduced health outcomes for people with chronic conditions might have been caused by a decrease in care management processes (CMPs) in primary care clinics METHODS Longitudinal cohort design with repeated survey-based measures of CMPs from 2017, 2019, and 2021 in 269 primary care clinics in Minnesota. RESULTS There were only small differences in organizational characteristics and no differences in overall CMPs between the 269 clinics analyzed and the 287 that only completed surveys in 1 or 2 years. Overall CMP scores rose by similar amounts (1.6% and 2.1%) from 2017 to 2019 and from 2019 to 2021. In 2021, CMP scores were lower in small medical groups than in large medical groups in 2017 (66.1% vs 78.5%, P CONCLUSIONS Although quite disrupted by the pandemic, care management processes for chronic disease care in these resilient primary care clinics actually increased from 2019 to 2021, at least in clinics that were part of large organizations. However, that was not true for clinics from smaller groups and perhaps for other areas of care. Key words: COVID-19; patient care management; primary health care; quality of health care, INTRODUCTION Over the past 2 years (2020, 2021), the COVID-19 pandemic has disrupted nearly every sector of the United States and world economy and everyone's lives. It has been particularly [...]

PURPOSE The aim of this study was to determine what strategies and factors are most important for high performance in the primary care of patients with diabetes. METHODS We performed a mixed-methods, cross-sectional, observational analysis of interviews and characteristics of primary care clinics in Minnesota and bordering areas. We compared strategies, facilitators, and barriers identified by 31 leaders of 17 clinics in high-, middle-, and low-performance quartiles on a standardized composite measure of diabetes outcomes for 416 of 586 primary care clinics. Semistructured interview data were combined with quantitative data regarding clinic performance and a survey of the presence of care management processes. RESULTS The interview analysis identified 10 themes providing unique insights into the factors and strategies characterizing the 3 performance groups. The main difference was the degree to which top-performing clinics used patient data to guide proactive and outreach methods to intensify treatment and monitor effect. Top clinics also appeared to view visit-based care management processes as necessary but insufficient, whereas all respondents regarded being part of a large system as mostly helpful. CONCLUSIONS Top-performing clinic approaches to diabetes care differ from lower-performing clinics primarily by emphasizing data-driven proactive outreach to patients to intensify treatment. Although confirmatory studies are needed, clinical leaders should consider the value of this paradigm shift in approach to care. Key words: quality of health care; diabetes mellitus; delivery of health care; primary health care; organizational culture, INTRODUCTION In a recent study of US National Health and Nutrition Examination Survey data, Kazemian et al reported that measures of diabetes care outcomes did not improve from 2005 to [...]

PURPOSE The purpose of this study was to assess whether primary care practices certified as medical homes differ in having the practice systems required for that designation and in attaining favorable outcomes for their patients with diabetes, and whether those systems are associated with better diabetes outcomes. METHODS We undertook a cross-sectional observational study, Understanding Infrastructure Transformation Effects on Diabetes (UNITED), of 586 Minnesota adult primary care practices, comparing those that were certified vs uncertified as medical homes in 2017, with analyses supplemented by previously published studies of these practices. We collected survey information about the presence of medical home practice systems for diabetes care and obtained 6 standardized measures of diabetes care collected yearly from all Minnesota practices. RESULTS Of 416 practices completing questionnaires (71% of all practices, 92% of participating practices), 394 had data on diabetes care measures. Uncertified practices (39%) were more likely than certified practices to be rural, but their patient populations were similar. Certified practices had more medical home practice systems (79.2% vs 74.9%, P =.01) and were more likely to meet a composite measure of optimal diabetes care (46.8% vs 43.2%, P CONCLUSIONS Practices certified as medical homes have more practice systems and higher performance on diabetes care than uncertified practices, but there is extensive overlap, and any differences may reflect self-selection for certification. Key words: diabetes mellitus; organizational innovation; patient-centered care; primary health care; quality assurance, health care; practice-based research, INTRODUCTION In the last 10 years, the concept of a medical home for patients, a patient-centered medical home (PCMH), has resurfaced from its origins in pediatrics in 1967. (1,2) The [...]

The large spectrum of limb morphologies reflects the wide evolutionary diversification of the basic pentadactyl pattern in tetrapods. In even-toed ungulates (artiodactyls, including cattle), limbs are adapted for running as a consequence of progressive reduction of their distal skeleton to symmetrical and elongated middle digits with hoofed phalanges. Here we analyse bovine embryos to establish that polarized gene expression is progressively lost during limb development in comparison to the mouse. Notably, the transcriptional upregulation of the Ptchl gene, which encodes a Sonic hedgehog (SHH) receptor, is disrupted specifically in the bovine limb bud mesenchyme. This is due to evolutionary alteration of a Ptchl cis-regulatory module, which no longer responds to graded SHH signalling during bovine handplate development. Our study provides a molecular explanation for the loss of digit asymmetry in bovine limb buds and suggests that modifications affecting the Ptchl cis-regulatory landscape have contributed to evolutionary diversification of artiodactyl limbs., A prime example of morphological evolution is the diversification of pentadactylous (five digits) limbs in tetrapods to serve a multitude of specialized needs such as grasping, digging, swimming, flying and [...]

Author(s): Mary E. Dickinson; Ann M. Flenniken; Xiao Ji; Lydia Teboul; Michael D. Wong; Jacqueline K. White; Terrence F. Meehan; Wolfgang J. Weninger; Henrik Westerberg; Hibret Adissu; Candice N. Baker; [...]

Xenoturbellida and Acoelomorpha are marine worms with contentious ancestry. Both were originally associated with the flatworms (Platyhelminthes), but molecular data have revised their phylogenetic positions, generally linking Xenoturbellida to the deuterostomes (1,2) and positioning the Acoelomorpha as the most basally branching bilaterian group(s) (3-6). Recent phylogenomic data suggested that Xenoturbellida and Acoelomorpha are sister taxa and together constitute an early branch of Bilateria (7). Here we assemble three independent data sets--mitochondrial genes, a phylogenomic data set of 38,330 amino-acid positions and new microRNA (miRNA) complements--and show that the position of Acoelomorpha is strongly affected by a long-branch attraction (LBA) artefact. When we minimize LBA we find consistent support for a position of both acoelomorphs and Xenoturbella within the deuterostomes. The most likely phylogeny links Xenoturbella and Acoelomorpha in a clade we call Xenacoelomorpha. The Xenacoelomorpha is the sister group of the Ambulacraria (hemichordates and echinoderms). We show that analyses of miRNA complements8 have been affected by character loss in the acoels and that both groups possess one miRNA and the gene Rsb66 otherwise specific to deuterostomes. In addition, Xenoturbella shares one miRNA with the ambulacrarians, and two with the acoels. This phylogeny makes sense of the shared characteristics of Xenoturbellida and Acoelomorpha, such as ciliary ultrastructure and diffuse nervous system, and implies the loss of various deuterostome characters in the Xenacoelomorpha including coelomic cavities, through gut and gill slits., In contrast to previous results (1,2,4,9,10) (Fig. la), two recent phylogenomic studies have suggested a sister group relationship between Acoelomorpha and Xenoturbella. These studies disagree over where this clade might [...]

Hagfish and lampreys are the only living representatives of the jawless vertebrates (agnathans), and compared with jawed vertebrates (gnathostomes), they provide insight into the embryology, genomics, and body plan of the ancestral vertebrate. However, this insight has been obscured by controversy over their interrelationships. Morphological cladistic analyses have identified lampreys and gnathostomes as closest relatives, whereas molecular phylogenetic studies recover a monophyletic Cyclostomata (hagfish and lampreys as closest relatives). Here, we show through deep sequencing of small RNA libraries, coupled with genomic surveys, that Cyclostomata is monophyletic: hagfish and lampreys share 4 unique microRNA families, 15 unique paralogues of more primitive microRNA families, and 22 unique substitutions to the mature gene products. Reanalysis of morphological data reveals that support for cyclostome paraphyly was based largely on incorrect character coding, and a revised dataset is not decisive on the mono- vs. paraphyly of cyclostomes. Furthermore, we show fundamental conservation of microRNA expression patterns among lamprey, hagfish, and gnathostome organs, implying that the role of microRNAs within specific organs is coincident with their appearance within the genome and is conserved through time. Together, these data support the monophyly of cyclostomes and suggest that the last common ancestor of all living vertebrates was a more complex organism than conventionally accepted by comparative morphologists and developmental biologists. complexity | cyclostomata | evolution | organ | homology doi/ 10.1073/pnas.1010350107

The causal basis of vertebrate complexity has been sought in genome duplication events (GDEs) that occurred during the emergence of vertebrates, but evidence beyond coincidence is wanting. MicroRNAs (miRNAs) have recently been identified as a viable causal factor in increasing organismal complexity through the action of these [approximately equal to]22-nt noncoding RNAs in regulating gene expression. Because miRNAs are continuously being added to animalian genomes, and, once integrated into a gene regulatory network, are strongly conserved in primary sequence and rarely secondarily lost, their evolutionary history can be accurately reconstructed. Here, using a combination of Northern analyses and genomic searches, we show that 41 miRNA families evolved at the base of Vertebrata, as they are found and/or detected in lamprey, but not in either ascidians or amphioxus (or any other nonchordate taxon). When placed into temporal context, the rate of miRNA acquisition and the extent of phenotypic evolution are anomalously high early in vertebrate history, far outstripping any other episode in chordate evolution. The genomic position of miRNA paralogues in humans, together with gene trees incorporating lamprey orthologues, indicates that although GDEs can account for an increase in the diversity of miRNA family members, which occurred before the last common ancestor of all living vertebrates, GDEs cannot account for the origin of these novel families themselves. We hypothesize that lying behind the origin of vertebrate complexity is the dramatic expansion of the noncoding RNA inventory including miRNAs, rather than an increase in the protein-encoding inventory caused by GDEs. genome duplication | lamprey | macroevolution | shark | chordate

Ship service electrical power consumption at the pier side is rapidly growing and now exceeds 10-MW power range on many of the latest commercial ships. Short circuit current interruption capability of the switchgear and cables servicing the ship load at the port dictate the use of medium voltage power distribution systems at voltages from 5- to 21-kV range. Many of the high power medium voltage electrical loads must operate during unloading and loading of the docked ships. At the same time, environment protection regulations in many sea ports (California's largest ports are examples of the most restrictive requirements) do not allow ships to operate their prime movers while at berth. Many ship operators and port authorities are struggling with the absence of appropriate standards and specifications for interconnecting the ship service loads to onshore power distribution systems. The intent of this paper is first to review the theory, practice, and existing interconnection standards and then to outline what can be done to achieve a secure, reliable, safe, and cost-effective operation of the ship service loads inside international ports. This paper will review the current state of cold ironing, existing applicable standards for ship interconnections to shore power, proven techniques for shore power interconnections, as well as approaches to mitigate challenges of high power and high voltage shore power. Index Terms--American Bureau of Shipping (ABS), cold ironing, Det Norske Veritas (DNV), Environmental Protection Agency (EPA), IEEE-45, IEEE-P1662, International Electrotechnical Commission (IEC), Lloyds, Mil-C-24368, shoreside power.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2006.07.037 Byline: Maria I. Arnone (a), Francesca Rizzo (a), Rosella Annunciata (a), R. Andrew Cameron (b), Kevin J. Peterson (c), Pedro Martinez (d)(e) Keywords: Hox; ParaHox; Colinearity; Gsx; lox; Cdx; Cluster; S. purpuratus; Evolution Abstract: The ANTP family of homeodomain transcription factors consists of three major groups, the NKL, the extended Hox, and the Hox/ParaHox family. Hox genes and ParaHox genes are often linked in the genome forming two clusters of genes, the Hox cluster and the ParaHox cluster, and are expressed along the major body axis in a nested fashion, following the relative positions of the genes within these clusters, a property called colinearity. While the presences of a Hox cluster and a ParaHox cluster appear to be primitive for bilaterians, few taxa have actually been examined for spatial and temporal colinearity, and, aside from chordates, even fewer still manifest it. Here we show that the ParaHox genes of the sea urchin Strongylocentrotus purpuratus show both spatial and temporal colinearity, but with peculiarities. Specifically, two of the three ParaHox genes-discovered through the S. purpuratus genome project-Sp-lox and Sp-Cdx, are expressed in the developing gut with nested domains in a spatially colinear manner. However, transcripts of Sp-Gsx, although anterior of Sp-lox, are detected in the ectoderm and not in the gut. Strikingly, the expression of the three ParaHox genes would follow temporal colinearity if they were clustered in the same order as in chordates, but each ParaHox gene is actually found on a different genomic scaffold (>300 kb each), which suggests that they are not linked into a single coherent cluster. Therefore, ParaHox genes are dispersed in the genome and are used during embryogenesis in a temporally and spatially coherent manner, whereas the Hox genes, now fully sequenced and annotated, are still linked and are employed as a complex only during the emergence of the adult body plan in the larva. Author Affiliation: (a) Stazione Zoologica 'Anton Dohrn', Villa Comunale, 80121 Napoli, Italy (b) Division of Biology 139-74, California Institute of Technology, Pasadena, CA 91125, USA (c) Department of Biological Sciences, Dartmouth College, Hanover, NH 03755, USA (d) Department de Genetica, Universitat de Barcelona, Av. Diagonal, 645, 08028 Barcelona, Spain (e) ICREA (Institut Catala de Recerca i Estudis Avancats), Barcelona, Spain Article History: Received 30 May 2006; Revised 20 July 2006; Accepted 27 July 2006

A study examines the parahox genes of sea urchin strongylocentrotus purpuratus which display temporal colinearity. The embryogenesis of the sea urchin is discussed along with its spatial and temporal colinearity.

Low phytic acid (lpa) crops have reductions in the amount of seed phytic acid (myo-inositol hexakisphosphate, Ins[P.sub.6]) and increases in inorganic phosphorus (Pi) with little change to the amount of total seed E In this study, four harley Ipa genotypes (lpa1-2, Ipa2-1, lpa3-1, and M955), backcross wild-type (wt) sib-selections, and original parental line 'Harringlon' were grown in the field over 2 yr. Developing seed was harvested once a week for 3 wk and then again at physiological maturity, and the seeds assayed for levels of total P, Pi, and phytic acid P. Total phosphorus concentration showed no consistent differences between the Ipa genotypes and Harrington. Inorganic P declined during development in the wt genotypes: however in Ipa genotypes, inorganic P declined during the first few weeks of development, and then increased from 24 d to maturity. Phylic acid concentration increased steadily during development for the wt lines and harley lpa1-1 and lpa2-1, although the increase was much slower in the lpa lines. The lpa3-1 and M955 had very little Ins[P.sub.6], accumulation until later in development, with little to no increase in the amount of phytic acid in mature seed of M955 compared to the developing seeds of lpa3-1. This information is useful in understanding liming of phosphorus accumulation in seeds, as well as the nature of the low phytic acid mutation in seed development.

Specific mammalian genes functionally and dynamically associate together within the nucleus. Yet, how an array of many genes along the chromosome sequence can be spatially organized and folded together is unknown. We investigated the 3D structure of a well-annotated, highly conserved 4.3-Mb region on mouse chromosome 14 that contains four clusters of genes separated by gene 'deserts.' In nuclei, this region forms multiple, nonrandom 'higher order' structures. These structures are based on the gene distribution pattern in primary sequence and are marked by preferential associations among multiple gene clusters. Associating gene clusters represent expressed chromatin, but their aggregation is not simply dependent on ongoing transcription. In chromosomes with aggregated gene clusters, gene deserts preferentially align with the nuclear periphery, providing evidence for chromosomal region architecture by specific associations with functional nuclear domains. Together, these data suggest dynamic, probabilistic 3D folding states for a contiguous megabase-scale chromosomal region, supporting the diverse activities of multiple genes and their conserved primary sequence organization.

Many marine invertebrates have a complex life cycle in which the egg develops into an intermediate planktic larval form rather than developing directly to the benthic juvenile stage. Because of the evolutionary and ecological complexity of pelagic-benthic life cycles, the reasons behind the origin of larvae and their subsequent maintenance over geological time are not well understood. Using both a molecular clock and the fossil record, I show that the initial exploitation of the predator-free pelagic realm by lecithotrophic larvae was achieved independently multiple times by the end of the Early Cambrian, and that the convergent evolution of planktotrophy from lecithotrophic ancestors evolved between the latest Cambrian and Middle Ordovician at least four, and possibly as many as eight, times. Both the exploitation of the pelagic realm by nonfeeding larvae and the acquisition of planktotrophy correlate in time with novel modes of benthic predation, including the dramatic rise in the number and type of epifaunal suspension feeders in the Early Ordovician. Keywords: larvae, Cambrian, Ordovician, suspension feeding, predation.

Land application of manure can increase P transfer in runoff, although the risk depends in part on the characteristics of the manure. We assessed this for calcareous soils using manures from swine (Sus domesticus) fed one of five barley varieties (Hordeum vulgare L.), including four low phytate mutants and a normal variety, to produce manures with a range of total P (6.8-4.9 g P [kg.sup.-1]), water-soluble P (4.3-8.0 g P [kg.sup.-1]), total N/P ratios (2.5:1-5.5:1), and total C/P ratios (31:1-67:1). Two experiments were conducted. First, manures were incorporated into three soils on a N (150 mg N [kg.sup.-1] soil) or P (27.5 mg P [kg.sup.-1] soil) basis three times during a 7-wk incubation. Second, 10 additional soils were incubated for 2 wk following a single P-based manure application (82.5 mg P [kg.sup.-1] soil). Water and NaHC[O.sub.3] (Olsen) extractable P were determined at regular intervals, with microbial P determined by fumigation-extraction after each incubation. For N-based application (i.e., variable P amendment), extractable P increased with total P applied. For P-based applications, the increase in soil P was more closely correlated to microbial P concentration than manure P composition or soil properties. These results suggest that stimulation of the microbial biomass by added organic C is important in determining soil P solubility following manure application.

Molecular clocks have the potential to shed light on the timing of early metazoan divergences, but differing algorithms and calibration points yield conspicuously discordant results. We argue here that competing molecular clock hypotheses should be testable in the fossil record, on the principle that fundamentally new grades of animal organization will have ecosystem-wide impacts. Using a set of seven nuclear-encoded protein sequences, we demonstrate the paraphyly of Porifera and calculate sponge/eumetazoan and cnidarian/bilaterian divergence times by using both distance [minimum evolution (ME)] and maximum likelihood (ML) molecular clocks; ME brackets the appearance of Eumetazoa between 634 and 604 Ma, whereas ML suggests it was between 867 and 748 Ma. Significantly, the ME, but not the ML, estimate is coincident with a major regime change in the Proterozoic acritarch record, including: (i) disappearance of low-diversity, evolutionarily static, pre-Ediacaran acanthomorphs; (ii) radiation of the high-diversity, short-lived Doushantuo-Pertatataka microbiota; and (iii) an order-of-magnitude increase in evolutionary turnover rate. We interpret this turnover as a consequence of the novel ecological challenges accompanying the evolution of the eumetazoan nervous system and gut. Thus, the more readily preserved microfossil record provides positive evidence for the absence of pre-Ediacaran eumetazoans and strongly supports the veracity, and therefore more general application, of the ME molecular clock. Porifera | acritarchs | Ediacaran | coevolution

About 75% of the total P in conventional soybean [Glycine max (L.) Merr.] seed is phytate P, which cannot be readily digested by nonruminant livestock, such as swine and poultry. The phytate P in soybean lines homozygous for the recessive alleles pha1 and pha2 is reduced to about 25% of the total P. The objective of this study was to determine the influence of low phytate (LP) on agronomic and seed traits of soybean. Three populations were developed by crossing three cultivars with normal phytate (NP) to the LP line CX1834-1-6. From each population, 10 LP and 10 NP lines were selected and grown in replicated tests at three Iowa environments during 2003. The mean total P of the LP and NP lines was not significantly different, but the mean phytate P, inorganic P, and other P were significantly different for the two types of lines in the three populations. The mean seedling emergence of the LP lines was 45% compared with 68% for the NP lines. The mean differences between the LP and NP lines for the other agronomic and seed traits were not significant in one or more of the populations. On the basis of these results, reduced seedling emergence will be a major factor to consider in the development of commercially viable cultivars with the pha1pha1pha2pha2 genotype for LP., PHYTATE P in soybean meal is largely unavailable to swine, poultry, and other nonruminant animals because they have little or none of the phytase enzyme in their digestive systems (Erdman, [...]

We have identified an NK2 family homeodomain transcription factor, SpNK2.1, in the sea urchin Strongylocentrotus purpuratus whose transcripts are initially detected within the apical plate ectoderm of the hatching blastula and are confined to the apical organ at least through 2 weeks of development. Protein localization studies demonstrate that SpNK2.1 is restricted to the apical plate epithelium, but is excluded from the nucleus of serotonergic neurons. The expression profile of SpNK2.1 is dictated via two separate regulatory systems. Initially, SpNK2.1 is restricted to the apical pole domain by [beta]-catenin-dependent processes operating along the animal vegetal axis, as evidenced by an expansion of SpNK2.1 expression upon cadherin overexpression. Starting at gastrulation, expression in the apical plate is maintained by SpDri, the sea urchin orthologue of dead ringer. Abrogation of SpDri results in the downregulation of SpNK2.1 after gastrulation, but SpDri is not necessary for the initial activation of SpNK2.1. Loss of function experiments using SpNK2.1-specific morpholino antisense oligonucleotides and SpNK2.1 overexpression experiments do not disrupt embryonic development and have no effect upon the development of neuronal components of the apical organ. Nonetheless, SpNK2.1 defines a new early territory of the sea urchin embryo. Keywords: NK2; Sea urchin; Territory

Accurately dating when the first bilaterally symmetrical animals arose is crucial to our understanding of early animal evolution. The earliest unequivocally bilaterian fossils are [approximately equal to]555 million years old. In contrast, molecular-clock analyses calibrated by using the fossil record of vertebrates estimate that vertebrates split from dipterans (Drosophila) [approximately equal to] 900 million years ago (Ma). Nonetheless, comparative genomic analyses suggest that a significant rate difference exists between vertebrates and dipterans, because the percentage difference between the genomes of mosquito and fly is greater than between fish and mouse, even though the vertebrate divergence is almost twice that of the dipteran. Here we show that the dipteran rate of molecular evolution is similar to other invertebrate taxa (echinoderms and bivalve molluses) but not to vertebrates, which significantly decreased their rate of molecular evolution with respect to invertebrates. Using a data set consisting of the concatenation of seven different amino acid sequences from 23 in-group taxa (giving a total of 11 different invertebrate calibration points scattered throughout the bilaterian tree and across the Phanerozoic), we estimate that the last common ancestor of bilaterians arose somewhere between 573 and 656 Ma, depending on the value assigned to the parameter scaling molecular substitution rate heterogeneity. These results are in accord with the known fossil record and support the view that the Cambrian explosion reflects, in part, the diversification of bilaterian phyla.

The Spdeadringer (Spdri) gene encodes an ARID-class transcription factor not previously known in sea urchin embryos. We show that Spdri is a key player in two separate developmental gene regulatory networks (GRNs). Spdri is expressed in a biphasic manner, first, after 12 h and until ingression in the skeletogenic descendants of the large micromeres; second, after about 20 h in the oral ectoderm, where its transcripts remain present at 30-50 mRNA molecules/cell far into development. In both territories, the periods of Spdri expression follow prior territorial specification events. The functional significance of each phase of expression was assessed by determining the effect of an [alpha]Spdri morpholino antisense oligonucleotide (MASO) on expression of 17 different mesodermal genes, 8 different oral ectoderm genes, and 18 other genes expressed specifically during endomesoderm specification. These effects were measured by quantitative PCR, supplemented by whole-mount in situ hybridization and morphological observations. Spdri is shown to act in the micromere descendants in the pathways that result in the expression of batteries of terminal skeletogenic genes. But, in the oral ectoderm, the same gene participates in the central GRN controlling oral ectoderm identity. Spdri is linked in the oral ectoderm GRN with several other genes encoding transcriptional regulators that are expressed specifically in various regions of the oral ectoderm. If its expression is blocked by treatment with [alpha]Spdri MASO, oral-specific features disappear and expression of the aboral ectoderm marker spec1 encompasses the whole of the ectoderm. In addition to disappearance of the oral ectoderm, morphological consequences of [alpha]Spdri MASO treatment include failure of spiculogenesis and of correct primary mesenchyme cell (pmc) patterning in the postgastrular embryo, and also failure of gastrulation. To further analyze these phenotypes, chimeric embryos were constructed consisting of two labeled micromeres combined with micromereless 4th cleavage host embryos; either the micromeres or the hosts contained [alpha]Spdri MASO. These experiments showed that, while Spdri expression is required autonomously for expression of skeletogenic genes prior to ingression, complete skeletogenesis also requires the expression of oral ectoderm patterning information. Presentation of this information on the oral side of the blastocoel in turn depends on Spdri expression in the oral ectoderm. Failure of gastrulation is not due to indirect interference with endomesodermal specification per se, since all endomesodermal genes tested function normally in [alpha]Spdri MASO embryos. Part of its cause is interference by [alpha]Spdri MASO with a late signaling function on the part of the micromere descendants that is needed to complete clearance of the Soxb1 repressor of gastrulation from the prospective endoderm, but in addition there is a nonautonomous oral ectoderm effect. Keywords: Gene regulatory network; Oral ectoderm; deadringer; Sea urchin embryo

Approximately one-third of all mammalian genes are essential for life. Phenotypes resulting from knockouts of these genes in mice have provided tremendous insight into gene function and congenital disorders. As part of the International Mouse Phenotyping Consortium effort to generate and phenotypically characterize 5,000 knockout mouse lines, here we identify 410 lethal genes during the production of the first 1,751 unique gene knockouts. Using a standardized phenotyping platform that incorporates high-resolution 3D imaging, we identify phenotypes at multiple time points for previously uncharacterized genes and additional phenotypes for genes with previously reported mutant phenotypes. Unexpectedly, our analysis reveals that incomplete penetrance and variable expressivity are common even on a defined genetic background. In addition, we show that human disease genes are enriched for essential genes, thus providing a dataset that facilitates the prioritization and validation of mutations identified in clinical sequencing efforts., Author(s): Mary E. Dickinson [1]; Ann M. Flenniken [2, 3]; Xiao Ji [4]; Lydia Teboul [5]; Michael D. Wong [2, 6]; Jacqueline K. White [7]; Terrence F. Meehan [8]; Wolfgang [...]

An initial demonstration showed that the 3',5'-ADP fragment of coenzyme A of a chromogenic substrate indolepropionyl-CoA (IPCoA) is important in the pig kidney medium-chain acyl-CoA dehydrogenase (MCAD)-catalyzed reaction. The effects of deletion of the 3'-phosphate group from octanoyl-Coa and butyryl-CoA were investigated, and turnover rate of the butyryl-CoA-dependent reaction was impaired, although turnover rate of the octanoyl-CoA-dependent reaction was enhanced. The thermodynamic aspects of enzyme-ligand interactions were investigated using isothermal microcalorimetry.

A diverse assemblage of invertebrate animals, some of which basically resemble the forms found in modern oceans, appears in the fossil record soon after the advent of the Cambrian period, though the first large multicellular animals clearly arose even earlier. How this occurred is among the intellectually challenging mysteries of biology. The solution to this mystery is likely to emerge, in part, from an understanding of the molecular processes by which modern animals use their genetic information to construct their body plans during embryonic development. We discuss a mechanistic hypothesis that was presented earlier as an explanation of the causal events underlying the 'Cambrian explosion,' and thus the divergence of large animal body plans., INTRODUCTION One of the most exciting and fundamentally important discoveries of paleontology is that remains of many animal phyla appear in the fossil record almost at once, during the geological [...]

Research was conducted to examine the effect of Glu-376-->Asp mutation on the ultraviolet spectral, thermodynamic and kinetic attributes for the binding of medium-chain Acyl-CoA dehydrogenase on selected CoA-ligands. Results revealed the pronounced effects of the E376D mutation on the binding of indoleacryloyl-CoA and acetoacetyl-CoA to the enzyme. The discriminatory effect of the mutation can be attributed to ligand-specific changes between CoA-ligands and FAD at the enzyme site.

Methods of site-directed mutagenesis were employed in the substitution of Glu-376 with by Asp, expressions of the wild-type and mutant enzymes in Escherichia coli and decontamination to homogeneity. The findings revealed that the Asp hindered that inactivation of the enzyme by 2-octynoyl-CoA and the turnover rate. The results indicated that the carboxyl group of Asp 376 does not act as an effective catalytic base as the carboxyl family of Glu-376.

Isothermal titration microcalorimetric techniques were used to determine the structural-functional and mechanistic role of octenoyl-CoA in the medium chain acyl-CoA dehydrogenase (MCAD) catalysis. Results reveal that the association constant of MCAD and octanoyl-CoA is pH-dependent. Furthermore, it is indicated that the standard entropy and standard enthalpy are inversely related to temperature.

An argument is proposed to explain the origin of large metazoans, based on the regulatory processes that underlie the morphogenetic organization of pattern in modern animals. Genetic regulatory systems similar to those used in modern, indirectly developing marine invertebrates are considered to indicate the Precambrian regulatory platform on which were erected innovations that underlie the development of macroscopic body plans. Those systems are genetic regulatory programs that produce groups of unspecified 'set-aside cells' and hierarchical regulatory programs that initially define regions of morphogenetic space in terms of domains of transcription factor expression. These ideas affect interpretation of the development of arthropods and chordates as well as interpretation of the role of the genes of the homeotic complex in embryogenesis., Large animals may first have existed during the latest Precambrian (Vendian) period, and fossils dated to the initial period of the Cambrian (1) indicate the de novo appearance at this [...]

The purification procedure was used to prepare the recombinant human liver medium-chain acyl-CoA dehydrogenase (HMCAD) from Escherichia coli host cells. A study of the mechanism of interaction of the enzyme with octanoyl-CoA, 2-octenoyl-CoA and 2-octanoyl-CoA indicates that all the C8-CoA molecules react with HMCAD-FAD forming Michaels complexes. Two isomerization reactions that follow the complex formation lead to structural changes in the molecules.

The medium-chain fatty acyl-CoA dehydrogenase catalyzes various reactions using the binding energy of the coenzyme A thioester's 3',5'-adenosine diphosphate moiety with substrate/product complexes formed containing aromatic and heterocyclic groups. The dehydrogenase and oxidase pathways are utilized for the reactions with the adenosine stabilizing the complexes and allowing the formation of an intermediary species through lowing the energy barrier. The slow decay of the intermediary because of kinetic instabilities causes the oxidase activity.

This review examines the biases and problems of the several approaches that have been attempted in the past and being considered presently for dating the time of origin of phyla. Molecular and paleontological approaches are elaborated pointing out the deficiencies of these seemingly reasonable solutions.