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I. Introduction 342 II. The "Forgotten" River: Anacostia 345 III. The Lower Duwamish "Waterway" 352 IV. "Don't Blame the Flint River" 359 V. Conclusion 370 I. INTRODUCTION Growing up in [...], Since appearing in modern form fifty years ago, the Clean Water Act has proven a powerful force for environmental justice, helping to clean up urban waterways across the country. Through establishment of water quality standards and enforcement of regulatory requirements, the Clean Water Act has compelled public authorities and private companies to upgrade infrastructure and curtail discharge of sewage and other industrial effluent. At the same time, urban communities have continued to struggle with water pollution beyond the reaches of the Clean Water Act. This Article briefly examines three such communities: the Anacostia area of Washington, D.C.; the neighborhoods along the Duwamish Waterway of Seattle, Washington; and the residents affected by the Flint Water Crisis in Flint, Michigan. In each case, people have used legal authorities beyond the Clean Water Act to help improve water quality and quality of life in these communities. Equally important may be the character of the people charged with protecting human health and the environment, as the failures leading to the Flint Water Crisis clearly demonstrate.

Immune response to therapeutic enzymes poses a detriment to patient safety and treatment outcome. Enzyme replacement therapy (ERT) is a standard therapeutic option for some types of mucopolysaccharidoses, including Morquio A syndrome caused by N-acetylgalactosamine-6-sulfate sulfatase (GALNS) deficiency. Current protocols tolerize patients using cytotoxic immunosuppressives, which can cause adverse effects. Here we show development of tolerance in Morquio A mice via oral delivery of peptide or GALNS for 10 days prior to ERT. Our results show that using an immunodominant peptide (I10) or the complete GALNS enzyme to orally induce tolerance to GALNS prior to ERT resulted in several improvements to ERT in mice: (a) decreased splenocyte proliferation after in vitro GALNS stimulation, (b) modulation of the cytokine secretion profile, (c) decrease in GALNS-specific IgG or IgE in plasma, (d) decreased GAG storage in liver, and (e) fewer circulating immune complexes in plasma. This model could be extrapolated to other lysosomal storage disorders in which immune response hinders ERT., Introduction Mucopolysaccharidosis type IVA (MPS IVA) or Morquio A syndrome (MIM ID #253000) is an autosomal recessive disorder caused by the deficiency of N-acetylgalactosamine-6-sulfate sulfatase (GALNS: E.C.3.1.6.4), resulting in accumulation [...]

Bariatric surgeries are integral to the management of obesity and its metabolic complications. However, these surgeries cause bone loss and increase fracture risk through poorly understood mechanisms. In a mouse model, vertical sleeve gastrectomy (VSG) caused trabecular and cortical bone loss that was independent of sex, body weight, and diet, and this loss was characterized by impaired osteoid mineralization and bone formation. VSG had a profound effect on the bone marrow niche, with rapid loss of marrow adipose tissue, and expansion of myeloid cellularity, leading to increased circulating neutrophils. Following VSG, circulating granulocyte-colony stimulating factor (G-CSF) was increased in mice, and was transiently elevated in a longitudinal study of humans. Elevation of G-CSF was found to recapitulate many effects of VSG on bone and the marrow niche. In addition to stimulatory effects of G-CSF on myelopoiesis, endogenous G-CSF suppressed development of marrow adipocytes and hindered accrual of peak cortical and trabecular bone. Effects of VSG on induction of neutrophils and depletion of marrow adiposity were reduced in mice deficient for G-CSF; however, bone mass was not influenced. Although not a primary mechanism for bone loss with VSG, G-CSF plays an intermediary role for effects of VSG on the bone marrow niche., Introduction The high incidence of obesity and type 2 diabetes mellitus represent important public health problems worldwide (1). According to the Centers for Disease Control, the incidence of obesity has [...]

The embryonic gut tube is a cylindrical structure from which the respiratory and gastrointestinal tracts develop.sup.1. Although the early emergence of the endoderm as an epithelial sheet.sup.2,3 and later morphogenesis of the definitive digestive and respiratory organs.sup.4-6 have been investigated, the intervening process of gut tube formation remains relatively understudied.sup.7,8. Here we investigate the molecular control of macroscopic forces underlying early morphogenesis of the gut tube in the chick embryo. The gut tube has been described as forming from two endodermal invaginations--the anterior intestinal portal (AIP) towards the rostral end of the embryo and the caudal intestinal portal (CIP) at the caudal end--that migrate towards one another, internalizing the endoderm until they meet at the yolk stalk (umbilicus in mammals).sup.1,6. Migration of the AIP to form foregut has been descriptively characterized.sup.8,9, but the hindgut is likely to form by a distinct mechanism that has not been fully explained.sup.10. We find that the hindgut is formed by collective cell movements through a stationary CIP, rather than by movement of the CIP itself. Further, combining in vivo imaging, biophysics and mathematical modelling with molecular and embryological approaches, we identify a contractile force gradient that drives cell movements in the hindgut-forming endoderm, enabling tissue-scale posterior extension of the forming hindgut tube. The force gradient, in turn, is established in response to a morphogenic gradient of fibroblast growth factor signalling. As a result, we propose that an important positive feedback arises, whereby contracting cells draw passive cells from low to high fibroblast growth factor levels, recruiting them to contract and pull more cells into the elongating hindgut. In addition to providing insight into the early gut development, these findings illustrate how large-scale tissue level forces can be traced to developmental signals during vertebrate morphogenesis.Cell-labelling experiments are used to demonstrate that the hindgut in the chick embryo is formed by cells moving through the stationary caudal intestinal portal as a result of a contractile force gradient directed by fibroblast growth factor signalling., Author(s): Nandan L. Nerurkar [sup.1] [sup.6] [sup.7] , ChangHee Lee [sup.1] , L. Mahadevan [sup.2] [sup.3] [sup.4] [sup.5] , Clifford J. Tabin [sup.1] Author Affiliations:(1) Department of Genetics, Harvard Medical [...]

The involvement of nitric oxide (NO) in preventing bone loss has long been hypothesized, but despite decades of research the mechanisms remain obscure. In this issue of the JCI, Jin et al. explored NO deficiency using human cell and mouse models that lacked argininosuccinate lyase (ASL), the enzyme involved in synthesizing arginine and NO production. Osteoblasts that did not express ASL produced less NO and failed to differentiate. Notably, in the context of Asl deficiency, heterozygous deletion of caveolin 1, which normally inhibits NO synthesis, restored NO production, osteoblast differentiation, glycolysis, and bone mass. These experiments suggest that ASL regulates arginine synthesis in osteoblasts, which leads to enhanced NO production and increased glucose metabolism. After a period when research slowed, these studies, like the legendary phoenix, renew the exploration of NO in bone biology, and provide exciting translational potential., The exploration of nitric oxide in bone biology Almost 30 years ago, Science declared nitric oxide (NO) 'molecule of the year,' based on a host of breakthrough discoveries and widespread [...]

Among the many fans of Emerita Professor Eileen Gauna, I probably have one of the thinnest claims to the honor of composing this tribute, having only spent one year with [...]

Author(s): Chloe Alexandre [1]; Alban Latremoliere [2, 3]; Ashley Ferreira [2, 3]; Giulia Miracca [2, 3]; Mihoko Yamamoto [1]; Thomas E Scammell (corresponding author) [1]; Clifford J Woolf (corresponding author) [...]

Background: Identifying factors that impair bone accrual during childhood is a critical step toward osteoporosis prevention. Exposure to per- and polyfluoroalkyl substances (PFASs) has been associated with lower bone mineral density, but data are limited, particularly in children. Methods: We studied 576 children in Project Viva, a Boston-area cohort of mother/child pairs recruited prenatally from 1999 to 2002. We quantified plasma concentrations of several PFASs and measured areal bone mineral density (aBMD) by dual-energy X-ray absorptiometry (DXA) in midchildhood. We used linear regression to examine associations between plasma concentrations of individual PFASs and aBMD z-score. We used weighted quantile sum (WQS) regression to examine the association of the PFAS mixture with aBMD z-score. All models were adjusted for maternal age, education, annual household income, census tract median household income, and child age, sex, race/ethnicity, dairy intake, physical activity, and year of blood draw. Results: Children were [mean [+ or -] standard deviation (SD)] 7.9[+ or -]0.8 years of age. The highest PFAS plasma concentrations were of perfluorooctanesulfonic acid (PFOS) {median [interquartile range (IQR)]: 6.4 (5.6) ng/mL} and perfluorooctanoic acid (PFOA) [median (IQR): 4.4 (3.2) ng/mL]. Using linear regression, children with higher plasma concentrations of PFOA, PFOS, and perfluorodecanoate (PFDA) had lower aBMD z-scores [e.g., [beta]: -0.16; 95% confidence interval (CI): -0.25, -0.06 per doubling of PFOA]. The PFAS mixture was negatively associated with aBMD z-score ([beta]: -0.16; 95% CI: -0.28, -0.04 per IQR increment of the mixture index). Conclusions: PFAS exposure may impair bone accrual in childhood and peak bone mass, an important determinant of lifelong skeletal health. https://doi.org/10.1289/EHP4918, Introduction Osteoporosis affects over 200 million adults worldwide, and associated fractures are costly, with high morbidity and mortality and limited treatment options (Reginster and Burlet 2006). Because bone accrues during [...]

Neuropathic pain is a major, intractable clinical problem and its pathophysiology is not well understood. Although recent gene expression profiling studies have enabled the identification of novel targets for pain therapy (1-4), classical study designs provide unclear results owing to the differential expression of hundreds of genes across sham and nerve-injured groups, which can be difficult to validate, particularly with respect to the specificity of pain modulation (5). To circumvent this, we used two outbred lines of rats (6), which are genetically similar except for being genetically segregated as a result of selective breeding for differences in neuropathic pain hypersensitivity (7). SerpinA3N, a serine protease inhibitor, was upregulated in the dorsal root ganglia (DRG) after nerve injury, which was further validated for its mouse homolog. Mice lacking SerpinA3N developed more neuropathic mechanical allodynia than wild-type (WT) mice, and exogenous delivery of SerpinA3N attenuated mechanical allodynia in WT mice. T lymphocytes infiltrate the DRG after nerve injury and release leukocyte elastase (LE), which was inhibited by SerpinA3N derived from DRG neurons. Genetic loss of LE or exogenous application of a LE inhibitor (Sivelastat) in WT mice attenuated neuropathic mechanical allodynia. Overall, we reveal a novel and clinically relevant role for a member of the serpin superfamily and a leukocyte elastase and crosstalk between neurons and T cells in the modulation of neuropathic pain., A differential pain phenotype in rats with high and low pain sensitivity is apparent 3 d after injury (7). To identify genes that are associated with the induction of neuropathic [...]

A reduction in the number of digits has evolved many times in tetrapods, particularly in cursorial mammals that travel over deserts and plains, yet the underlying developmental mechanisms have remained elusive. Here we show that digit loss can occur both during early limb patterning and at later post-patterning stages of chondrogenesis. In the 'odd-toed' jerboa (Dipus sagitta) and horse and the 'even-toed' camel, extensive cell death sculpts the tissue around the remaining toes. In contrast, digit loss in the pig is orchestrated by earlier limb patterning mechanisms including downregulation of Ptchl expression but no increase in cell death. Together these data demonstrate remarkable plasticity in the mechanisms of vertebrate limb evolution and shed light on the complexity of morphological convergence, particularly within the artiodactyl lineage., Tetrapod limbs evolved adaptations for running, swimming, flying and many other tasks, each reflected in functional modifications to their morphology. Digit reduction, a decrease in the number of digits from [...]

Patient bone mineral density (BMD) predicts the likelihood of osteoporotic fracture. While substantial progress has been made toward elucidating the genetic determinants of BMD, our understanding of the factors involved remains incomplete. Here, using a systems genetics approach in the mouse, we predicted that bicaudal C homolog 1 (Bicc1), which encodes an RNA-binding protein, is responsible for a BMD quantitative trait locus (QTL) located on murine chromosome 10. Consistent with this prediction, mice heterozygous for a null allele of Bicc1 had low BMD. We used a coexpression network-based approach to determine how Bicc1 influences BMD. Based on this analysis, we inferred that Bicc1 was involved in osteoblast differentiation and that polycystic kidney disease 2 (Pkd2) was a downstream target of Bicc1. Knock down of Bicc1 and Pkd2 impaired osteoblastogenesis, and Bicc1 deficiency-dependent osteoblast defects were rescued by Pkd2 overexpression. Last, in 2 human BMD genome-wide association (GWAS) meta-analyses, we identified SNPs in BICC1 and PKD2 that were associated with BMD. These results, in both mice and humans, identify Bicc1 as a genetic determinant of osteoblastogenesis and BMD and suggest that it does so by regulating Pkd2 transcript levels., Introduction Osteoporosis is a disease characterized by low bone mass, skeletal fragility, and increased risk of fracture (1). Of the traits intrinsic to bone that influence its strength, bone mineral [...]

Author(s): Misty R. Riddle [1]; Ariel C. Aspiras [1]; Karin Gaudenz [2]; Robert Peu [2]; Jenny Y. Sung [2]; Brian Martineau [1]; Megan Peavey [1]; Andrew C. Box [2]; Julius [...]

Nociceptor sensory neurons are specialized to detect potentially damaging stimuli, protecting the organism by initiating the sensation of pain and eliciting defensive behaviours. Bacterial infections produce pain by unknown molecular mechanisms, although they are presumed to be secondary to immune activation. Here we demonstrate that bacteria directly activate nociceptors, and that the immune response mediated through TLR2, MyD88, T cells, B cells, and neutrophils and monocytes is not necessary for Staphylococcus aureus-induced pain in mice. Mechanical and thermal hyperalgesia in mice is correlated with live bacterial load rather than tissue swelling or immune activation. Bacteria induce calcium flux and action potentials in nociceptor neurons, in part via bacterial N-formylated peptides and the pore-forming toxin α-haemolysin, through distinct mechanisms. Specific ablation of Nav1.8-lineage neurons, which include nociceptors, abrogated pain during bacterial infection, but concurrently increased local immune infiltration and lymphadenopathy of the draining lymph node. Thus, bacterial pathogens produce pain by directly activating sensory neurons that modulate inflammation, an unsuspected role for the nervous system in host-pathogen interactions., A dense network of low- and high-threshold sensory nerves innervate peripheral tissues including the skin, respiratory tract and gastrointestinal tract, which are often exposed to bacterial pathogens. Bacterial infection induces [...]

CLP1 was the first mammalian RNA kinase to be identified. However, determining its in vivo function has been elusive. Here we generated kinase-dead Clpl ([Clp1.sup.K/K]) mice that show a progressive loss of spinal motor neurons associated with axonal degeneration in the peripheral nerves and denervation of neuromuscular junctions, resulting in impaired motor function, muscle weakness, paralysis and fatal respiratory failure. Transgenic rescue experiments show that CLP1 functions in motor neurons. Mechanistically, loss of CLP1 activity results in accumulation of a novel set of small RNA fragments, derived from aberrant processing of tyrosine pre-transfer RNA. These tRNA fragments sensitize cells to oxidative-stress-induced p53 (also known as TRP53) activation and p53-dependent cell death. Genetic inactivation of p53 rescues [Clp1.sup.K/K] mice from the motor neuron loss, muscle denervation and respiratory failure. Our experiments uncover a mechanistic link between tRNA processing, formation of a new RNA species and progressive loss of lower motor neurons regulated by p53., RNA molecules undergo co- and post-transcriptional processing, leading to mature, functional RNAs. In mammals and archaea CLP1 proteins are kinases that phosphorylate the 5' hydroxyl ends of RNA (1-3). Human [...]

The wide diversity of skeletal proportions in mammals is evident upon a survey of any natural history museum's collections and allows us to distinguish between species even when reduced to [...]

Insulin-like growth factor 1 (IGF-1), the most abundant growth factor in the bone matrix, maintains bone mass in adulthood. We now report that IGF-1 released from the bone matrix during bone remodeling stimulates osteoblastic differentiation of recruited mesenchymal stem cells (MSCs) by activation of mammalian target of rapamycin (mTOR), thus maintaining proper bone microarchitecture and mass. Mice with knockout of the IGF-1 receptor (Igf1r) in their preosteoblastic cells showed lower bone mass and mineral deposition rates than wild-type mice. Further, MSCs from Igf1rflox/flox mice with Igf1r deleted by a Cre adenovirus in vitro, although recruited to the bone surface after implantation, were unable to differentiate into osteoblasts. We also found that the concentrations of IGF-1 in the bone matrix and marrow of aged rats were lower than in those of young rats and directly correlated with the age-related decrease in bone mass. Likewise, in age-related osteoporosis in humans, we found that bone marrow IGF-1 concentrations were 40% lower in individuals with osteoporosis than in individuals without osteoporosis. Notably, injection of IGF-1 plus IGF binding protein 3 (IGFBP3), but not injection of IGF-1 alone, increased the concentration of IGF-1 in the bone matrix and stimulated new bone formation in aged rats. Together, these results provide mechanistic insight into how IGF-1 maintains adult bone mass, while also providing a further rationale for its therapeutic targeting to treat age-related osteoporosis., Bone mass peaks in mid or late adolescence, plateaus for several years and then inexorably declines to a point, usually in older individuals, during which there is increased skeletal fragility [...]

Chronic pain is highly variable between individuals, as is the response to analgesics. Although much of the variability in chronic pain and analgesic response is heritable, an understanding of the [...]

The developing vertebrate gut tube forms a reproducible looped pattern as it grows into the body cavity. Here we use developmental experiments to eliminate alternative models and show that gut looping morphogenesis is driven by the homogeneous and isotropic forces that arise from the relative growth between the gut tube and the anchoring dorsal mesenteric sheet, tissues that grow at different rates. A simple physical mimic, using a differentially strained composite of a pliable rubber tube and a soft latex sheet is consistent with this mechanism and produces similar patterns. We devise a mathematical theory and a computational model for the number, size and shape of intestinal loops based solely on the measurable geometry, elasticity and relative growth of the tissues. The predictions of our theory are quantitatively consistent with observations of intestinal loops at different stages of development in the chick embryo. Our model also accounts for the qualitative and quantitative variation in the distinct gut looping patterns seen in a variety of species including quail, finch and mouse, illuminating how the simple macroscopic mechanics of differential growth drives the morphology of the developing gut., Understanding morphogenesis, the origin of shape in anatomical structures, organs and organisms, has always been a central goal of developmental biology. Historically, the subject focused on the morphology and dynamics [...]

Although the Internet is a beneficial tool, some youth are at risk for being victimized by Internet predators. School counselors are in a unique position to assist in efforts to prevent online victimizations because of their continual interaction with students, parents, and other school faculty. This article provides school counselors with information about youth Internet use; risk factors associated with online victimizations; and recommendations to assist youth, parents, and families in improving Internet safety practices., The Internet is widely used among youth in the United States for academic purposes, to communicate with friends, and as a source of entertainment (Gross, 2004; Lenhart & Madden, 2007). [...]

Despite substantial investment by the pharmaceutical industry over several decades, there has been little progress in developing new, efficacious and safe analgesics. As a result, many large pharmaceutical companies are leaving the area of pain medication. Nevertheless, the chances of success could increase if analgesic drug development strategy changed. To achieve such a paradigm shift we must understand why development of drugs for pain relief is so challenging., Pain is a major health problem that substantially reduces quality of life and imparts high health costs and economic loss to society. Nevertheless, many major pharmaceutical companies are leaving the [...]

New gene regulation study tools such as microRNA (miRNA or miR) analysis may provide unique insights into the remarkable ability of the liver to regenerate. In addition, we have previously shown that ursodeoxycholic acid (UDCA) modulates mRNA levels during liver regeneration. Bile acids are also homeotrophic sensors of functional hepatic capacity. The present study was designed to determine whether miRNAs are modulated in rats following 70% partial hepatectomy (PH) and elucidate the role of UDCA in regulating miRNA expression during liver regeneration (LR). Total RNA was isolated from livers harvested at 3-72 h following 70% PH or sham operations, from both 0.4% (wt/wt) UDCA and control diet-fed animals. By using a custom microarray platform we found that several miRNAs are significantly altered after PH by > 1.5-fold, including some previously described as modulators of cell proliferation, differentiation, and death. In particular, expression of miR-21 was increased after PH. Functional modulation of miR-21 in primary rat hepatocytes increased cell proliferation and viability. Importantly, UDCA was a strong inducer of miR-21 both during LR and in cultured HepG2 cells. In fact, UDCA feeding appeared to induce a sustained increase of proliferative miRNAs observed at early time points after PH. In conclusion, miRNAs, in particular miR-21, may play a significant role in modulating proliferation and cell cycle progression genes after PH. miR-21 is additionally induced by UDCA in both regenerating rat liver and in vitro, which may represent a new mechanism behind UDCA biological functions. bile acids; liver regeneration; miR-21; miRNAs doi: 10.1152/ajpgi.00216.2010.

Defective RNA metabolism is an emerging mechanism involved in ALS pathogenesis and possibly in other neurodegenerative disorders. Here, we show that microRNA (miRNA) activity is essential for long-term survival of postmitotic spinal motor neurons (SMNs) in vivo. Thus, mice that do not process miRNA in SMNs exhibit hallmarks of spinal muscular atrophy (SMA), including sclerosis of the spinal cord ventral horns, aberrant end plate architecture, and myofiber atrophy with signs of denervation. Furthermore, a neurofilament heavy subunit previously implicated in motor neuron degeneration is specifically up-regulated in miRNA-deficient SMNs. We demonstrate that the heavy neurofilament subunit is a target of miR-9, a miRNA that is specifically down-regulated in a genetic model of SMA. These data provide evidence for miRNA function in SMN diseases and emphasize the potential role of miR-9--based regulatory mechanisms in adult neurons and neurodegenerative states. ALS | Dicer | microRNA | motor neuron | neurodegeneration doi/ 10.1073/pnas.1006151107

Peroxisome proliferator-activated receptor-[gamma] (PPAR[gamma]) is a nuclear receptor that functions as a master transcriptional regulator of adipocyte conversion. During PPAR[gamma] transactivation, multiple signaling pathways interact with one another, leading to the differentiation of both white and brown adipose tissue. Ligand activation of the PPAR[gamma]-RXR heterodimer complex also enhances insulin sensitivity, and this property has been heavily exploited to develop effective pharmacotherapies for the treatment of type 2 diabetes mellitus. PPAR[gamma] is also expressed in stem cells and plays a critical role in mesenchymal stromal cell differentiation and lineage determination events. The many facets of PPAR[gamma] activity within the bone marrow niche where adipocytes, osteoblasts, and hematopoietic cells reside make this molecule an attractive target for pharmacological investigation. Additional findings that osteoblasts can alter energy metabolism by influencing adiposity and insulin sensitivity, and observations of decreased bone turnover in diabetic subjects, underscore the contribution of the skeleton to systemic energy requirements. Studies into the role of PPAR[gamma] in skeletal acquisition and maintenance may lead to a better understanding of the molecular mechanisms governing stromal cell differentiation in the mesenchyme compartment and whether PPAR[gamma] activity can be manipulated to benefit skeletal remodeling events and energy metabolism. peroxisome proliferator-activated receptor-[gamma]; bone remodeling; energy metabolism doi: 10.1152/ajpendo.00157.2010.

Nocturnin (NOC) is a circadian-regulated protein related to the yeast family of transcription factors involved in the cellular response to nutrient status. In mammals, NOC functions as a deadenylase but lacks a transcriptional activation domain. It is highly expressed in bone-marrow stromal cells (BMSCs), hepatocytes, and adipocytes. In BMSCs exposed to the PPAR-[gamma] (peroxisome proliferator-activated receptor-[gamma]) agonist rosiglitazone, Noc expression was enhanced 30-fold. Previously, we reported that [Noc.sup.-/-] mice had low body temperature, were protected from diet-induced obesity, and most importantly exhibited absence of Pparg circadian rhythmicity on a high-fat diet. Consistent with its role in influencing BMSCs allocation, [Noc.sup.-/-] mice have reduced bone marrow adiposity and high bone mass. In that same vein, NOC overexpression enhances adipogenesis in 3T3-L1 cells but negatively regulates osteogenesis in MC3T3-E1 cells. NOC and a mutated form, which lacks deadenylase activity, bind to PPAR-[gamma] and markedly enhance PPAR-[gamma] transcriptional activity. Both WT and mutant NOC facilitate nuclear translocation of PPAR-[gamma]. Importantly, NOC-mediated nuclear translocation of PPAR-[gamma] is blocked by a short peptide fragment of NOC that inhibits its physical interaction with PPAR-[gamma]. The inhibitory effect of this NOC-peptide was partially reversed by rosiglitazone, suggesting that effect of NOC on PPAR-[gamma] nuclear translocation may be independent of ligand-mediated PPAR-[gamma] activation. In sum, Noc plays a unique role in the regulation of mesenchymal stem-cell lineage allocation by modulating PPAR-[gamma] activity through nuclear translocation. These data illustrate a unique mechanism whereby a nutrient-responsive gene influences BMSCs differentiation, adipogenesis, and ultimately body composition. doi/ 10.1073/pnas.1000788107

MicroRNAs (miRNAs) have previously been implicated in a number of developmental processes, including development of the ventricular myocardium of the heart. To determine what, if any, additional roles miRNAs play in cardiogenesis, we deleted the miRNA-processing enzyme Dicer specifically in the developing murine heart. Embryos lacking cardiac Dicer lived longer than reported in previous studies using different alleles to remove cardiac Dicer activity and displayed a highly penetrant phenotype of double outlet right ventricle with a concurrent ventricular septal defect. Before the defect's onset, Pitx2c and Sema3c, both required for outflow tract morphogenesis, were up-regulated in Dicer-deficient hearts. Interestingly, mesenchymal apoptosis in the outflow tract normally required for outflow tract alignment was greatly decreased in the mutants, likely contributing directly to the observed phenotype. In sum, we demonstrate here a specific developmental process, that of outflow tract morphogenesis, being hindered by the deletion of miRNAs during cardiogenesis. www.pnas.org/cgi/doi/1073/pnas.0912870107

Kren BT, Wong PY-P, Shiota A, Zhang X, Zeng Y, Steer CJ. Polysome trafficking of transcripts and microRNAs in regenerating liver after partial hepatectomy. Am J Physiol Gastrointest Liver Physiol 297: G1181-G1192, 2009. First published October l, 2009; doi: 10.1152/ajpgi.90636.2008.--Liver regeneration after 70% partial hepatectomy (PH) in rats induces >95% of hepatocytes to undergo two rounds of semisynchronous cell replication. Gene expression is controlled primarily by posttranscriptional processing, including changes in mRNA stability. However, the translational activity of a specific mRNA can also be modulated after PH, resulting in significant uncoupling of protein and transcript levels relative to quiescent liver for many genes including c-myc and p53. Although the precise mechanism by which this uncoupling occurs is unknown, the polysoreal association of mRNA and microRNA (miRNA) can significantly modulate rate of decay as well as translational activity. Thus we characterized the association of c-myc and p53 mRNAs and miRNAs in free and cytoskeleton- and membrane-bound polysome populations 3, 6, and 24 h after PH. The transcripts for c-myc and p53 were differentially distributed in the three discrete polysome populations, and this was dramatically modulated during liver regeneration. Nascent polysome-associated p53 and c-myc proteins were also differentially expressed in the free and cytoskeleton- and membrane-bound polysomes and significantly uncoupled from transcript levels relative to nonresected liver. At least 85 miRNAs were associated with the three polysome populations, and their abundance and distribution changed significantly during liver regeneration. These data suggest that posttranscriptional control of c-myc and p53 protein expression is associated with the translocation of transcripts between the different polyribosomes. The alteration of expression for the same transcript in different polysome populations may, in part, be due to the action of miRNAs. c-myc; liver regeneration; p53 doi: 10.1152/ajpgi.90636.2008

Patterning of the vertebrate axial skeleton requires precise spatial and temporal control of Hox gene expression during embryonic development. MicroRNAs (miRNAs) are recently described modulators of gene activity, and members of the miR-196 and miR-10 families have been shown to target several Hox genes in vivo. Testing miRNA function in mice is complicated by potential redundancy between family members. To circumvent this, we have developed protocols for introducing modified antisense oligonucleotides (antagomiRs) in ovo during chick development. Using this approach, we identify a layer of regulatory control provided by the miR-196 family in defining the boundary of Hox gene expression along the anterior-posterior (A-P) embryonic axis. Following knockdown of miR-196, we observe a homeotic transformation of the last cervical vertebrae toward a thoracic identity. This phenotypic alteration is, in part, due to an anterior expansion of Hoxb8 gene expression and consolidates the in vivo relevance of posttranscriptional Hox gene regulation provided by miRNAs in the complex hierarchies governing axial pattering. axial patterning | microRNA | homeotic transformation www.pnas.org/cgi/doi/10.1073/pnas.0910374106

We conducted a genetic analysis of the developing temporo-mandibular or temporomandi-bular joint (TMJ), a highly specialized synovial joint that permits movement and function of the mammalian jaw. First, we used laser capture microdissection to perform a genome-wide expression analysis of each of its developing components. The expression patterns of genes identified in this screen were examined in the TMJ and compared with those of other synovial joints, including the shoulder and the hip joints. Striking differences were noted, indicating that the TMJ forms via a distinct molecular program. Several components of the hedgehog (Hh) signaling pathway are among the genes identified in the screen, including Gli2, which is expressed specifically in the condyle and in the disk of the developing TMJ. We found that mice deficient in Gli2 display aberrant TMJ development such that the condyle loses its growth-plate-like cellular organization and no disk is formed. In addition, we used a conditional strategy to remove Smo, a positive effector of the Hh signaling pathway, from chondrocyte progenitors. This cell autonomous loss of Hh signaling allows for disk formation, but the resulting structure fails to separate from the condyle. Thus, these experiments establish that Hh signaling acts at two distinct steps in disk morphogenesis, condyle initiation, and disk-condyle separation and provide a molecular framework for future studies of the TMJ. Indian hedgehog | Gli2 | synovial joints | microarray doi/10.1073/pnas.0908836106

Phocomelia is a devastating, rare congenital limb malformation in which the long bones are shorter than normal, with the upper portion of the limb being most severely affected. In extreme cases, the hands or fingers are attached directly to the shoulder and the most proximal elements (those closest to the shoulder) are entirely missing. This disorder, previously known in both autosomal recessive and sporadic forms, showed a marked increase in incidence in the early 1960s due to the tragic toxicological effects of the drug thalidomide, which had been prescribed as a mild sedative (1,2). This human birth defect is mimicked in developing chick limb buds exposed to X-irradiation (3-5). Both X-irradiation (5) and thalidomide-induced phocomelia (5,6) have been interpreted as patterning defects in the context of the progress zone model, which states that a cell's proximodistal identity is determined by the length of time spent in a distal limb region termed the 'progress zone' (7). Indeed, studies of X-irradiation-induced phocomelia have served as one of the two major experimental lines of evidence supporting the validity of the progress zone model. Here, using a combination of molecular analysis and lineage tracing in chick, we show that X-irradiation-induced phocomelia is fundamentally not a patterning defect, but rather results from a time-dependent loss of skeletal progenitors. Because skeletal condensation proceeds from the shoulder to fingers (in a proximal to distal direction), the proximal elements are differentially affected in limb buds exposed to radiation at early stages. This conclusion changes the framework for considering the effect of thalidomide and other forms of phocomelia, suggesting the possibility that the aetiology lies not in a defect in the patterning process, but rather in progenitor cell survival and differentiation. Moreover, molecular evidence that proximodistal patterning is unaffected after X-irradiation does not support the predictions of the progress zone model., According to the progress zone model (7), proximodistal structures develop under the influence of a continuous signal, now understood to be a fibroblast growth factor (FGF) (8), produced by the [...]

Liver sinusoidal endothelial cells are a major endogenous source of Factor VIII (FVIII), lack of which causes the human congenital bleeding disorder hemophilia A. Despite extensive efforts, gene therapy using viral vectors has shown little success in clinical hemophilia trials. Here we achieved cell type--specific gene targeting using hyaluronan- and asialoorosomucoid-coated nanocapsules, generated using dispersion atomization, to direct genes to liver sinusoidal endothelial cells and hepatocytes, respectively. To highlight the therapeutic potential of this approach, we encapsulated Sleeping Beauty transposon expressing the B domain--deleted canine FVIII in cis with Sleeping Beauty transposase in hyaluronan nanocapsules and injected them intravenously into hemophilia A mice. The treated mice exhibited activated partial thromboplastin times that were comparable to those of wild-type mice at 5 and 50 weeks and substantially shorter than those of untreated controls at the same time points. Further, plasma FVIII activity in the treated hemophilia A mice was nearly identical to that in wild-type mice through 50 weeks, while untreated hemophilia A mice exhibited no detectable FVIII activity. Thus, Sleeping Beauty transposon targeted to liver sinusoidal endothelial cells provided long-term expression of FVIII, without apparent antibody formation, and improved the phenotype of hemophilia A mice., Introduction The delivery of genes to treat metabolic disease resulting from a defective or absent protein remains a significant challenge in medicine. Hemophilia A is an X-linked congenital bleeding disorder [...]

In vertebrates, the readily apparent left/right (L/R) anatomical asymmetries of the internal organs can be traced to molecular events initiated at or near the time of gastrulation. However, the earliest steps of this process do not seem to be universally conserved. In particular, how this axis is first defined in chicks has remained problematic. Here we show that asymmetric cell rearrangements take place within chick embryos, creating a leftward movement of ceils around the node. It is the relative displacement of ceils expressing sonic hedgehog (Shh) and fibroblast growth factor 8 (Fgf8) that is responsible for establishing their asymmetric expression patterns. The creation of asymmetric expression domains as a passive effect of cell movements represents an alternative strategy for breaking L/R symmetry in gene activity.

It is suggested that the path to modern humanity can be understood as a sequence pf phases and that the shift in phases has a simple trigger but immensely complex and far-reaching consequences. It is also argued that cercopithecene monkey provides analogies that can help clarify these phase shifts.

This paper provides a brief history of the F-16XL-1 aircraft, its role in the High-Speed Research Program, and how it was morphed into the Cranked-Arrow Wing Aerodynamics Project. Various flight, wind-tunnel, and computational fluid dynamics data sets were generated as part of the project. These unique and open flight data sets for surface pressures, boundary-layer profiles, and skin-friction distributions, along with surface flow data, are described and sample data comparisons are given. This is followed by a description of how the project became internationally known as Cranked-Arrow Wing Aerodynamics Project International and is concluded by an introduction to the results of a four-year computational predictive study of data collected at flight conditions by participating researchers.

A cardinal feature of peripheral inflammation is pain. The most common way of managing inflammatory pain is to use nonsteroidal antiinflammatory agents (NSAIDs) that reduce prostanoid production, for example, selective inhibitors of COX2. Prostaglandins produced after induction of COX2 in immune cells in inflamed tissue contribute both to the inflammation itself and to pain hypersensitivity, acting on peripheral terminals of nociceptors. COX2 is also induced after peripheral inflammation in neurons in the CNS, where it aids in developing a central component of inflammatory pain hypersensitivity by increasing neuronal excitation and reducing inhibition. We engineered mice with conditional deletion of Cox2 in neurons and glial cells to determine the relative contribution of peripheral and central COX2 to inflammatory pain hypersensitivity. In these mice, basal nociceptive pain was unchanged, as was the extent of peripheral inflammation, inflammatory thermal pain hypersensitivity, and fever induced by lipopolysaccharide. By contrast, peripheral inflammation--induced COX2 expression in the spinal cord was reduced, and mechanical hypersensitivity after both peripheral soft tissue and periarticular inflammation was abolished. Mechanical pain is a major symptom of most inflammatory conditions, such as postoperative pain and arthritis, and induction of COX2 in neural cells in the CNS seems to contribute to this., Introduction COXs catalyze the first reactions in PG synthesis to form [PGH.sub.2]. Tissue-specific isomerases (PG synthases) convert [PGH.sub.2] into 4 different PG isoforms (1), (2), which exert their biological actions [...]

Byline: Jeremy J. Cordingley (1), Dirk Vlasselaers (2), Natalie C. Dormand (1), Pieter J. Wouters (2), Stephen D. Squire (1), Ludovic J. Chassin (3), Malgorzata E. Wilinska (3), Clifford J. Morgan (1), Roman Hovorka (3), Greet den Berghe (2) Keywords: Hyperglycaemia; Glucose; Critical care; Insulin; Model Predictive Control; Algorithm Abstract: Objective To investigate the effectiveness of an enhanced software Model Predictive Control (eMPC) algorithm for intravenous insulin infusion, targeted at tight glucose control in critically ill patients, over 72 h, in two intensive care units with different management protocols. Design Comparison with standard care in a two center open randomized clinical trial. Setting Two adult intensive care units in University Hospitals. Patients and participants Thirty-four critically ill patients with hyperglycaemia (glucose >120 mg/dL) or already receiving insulin infusion. Interventions Patients were randomized, within each ICU, to intravenous insulin infusion advised by eMPC algorithm or the ICU's standard insulin infusion administration regimen. Measurements and results Arterial glucose concentration was measured at study entry and when advised by eMPC or measured as part of standard care. Time-weighted average glucose concentrations in patients receiving eMPC advised insulin infusions were similar [104 mg/dL (5.8 mmol/L)] in both ICUs. eMPC advised glucose measurement interval was significantly different between ICUs (1.1 vs. 1.8 h, P < 0.01). The standard care insulin algorithms resulted in significantly different time-weighted average glucose concentrations between ICUs [128 vs. 99 mg/dL (7.1 vs. 5.5 mmol/L), P < 0.01]. Conclusions In this feasibility study the eMPC algorithm provided similar, effective and safe tight glucose control over 72 h in critically ill patients in two different ICUs. Further development is required to reduce glucose sampling interval while maintaining a low risk of hypoglycaemia. Author Affiliation: (1) Adult Intensive Care Unit, Royal Brompton Hospital, Sydney Street, London, UK (2) Intensive Care Unit, University Hospital, Gasthuisberg, Leuven, Belgium (3) Department of Paediatrics, University of Cambridge, Cambridge, UK Article History: Registration Date: 16/07/2008 Received Date: 02/12/2007 Accepted Date: 03/07/2008 Online Date: 26/07/2008 Article note: An erratum to this article can be found at http://dx.doi.org/10.1007/s00134-008-1342-y

The blind Mexican cave tetra, Astyanax mexicanus, is a unique model system for the study of parallelism and the evolution of cave-adapted traits. Understanding the genetic basis for these traits has recently become feasible thanks to production of a genome-wide linkage map and quantitative trait association analyses. The selection of suitable candidate genes controlling quantitative traits remains challenging, however, in the absence of a physical genome. Here, we describe the integration of multiple linkage maps generated in four separate crosses between surface, cave, and hybrid forms of A. mexicanus. We performed exhaustive BLAST analyses of genomic markers populating this integrated map against sequenced genomes of numerous taxa, ranging from yeast to amniotes. We found the largest number of identified sequences (228), with the most expect (E) values < [10.sup.-5] (95), in the zebrafish Danio rerio. The most significant hits were assembled into an 'anchored' linkage map with Danio, revealing numerous regions of conserved synteny, many of which are shared across critical regions of identified quantitative trait loci (QTL). Using this anchored map, we predicted the positions of 21 test genes on the integrated linkage map and verified that 18 of these are found in locations homologous to their chromosomal positions in D. rerio. The anchored map allowed the identification of four candidate genes for QTL relating to rib number and eye size. The map we have generated will greatly accelerate the production of viable lists of additional candidate genes involved in the development and evolution of cave-specific traits in A. mexicanus. sequence homology | physical genome | evolution | quantitative trait locus

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1744-7976.2008.00147.x Byline: Troy G. Schmitz (1), Christopher R. Giese (2), Clifford J. Shultz II (3) Abstract: The qualitative impacts of European Union (EU) enlargement on intervention prices, variable import levies, and export restitution payments for cereal under the Common Agricultural Policy (CAP) are analyzed using a partial equilibrium framework for EU cereal crops. The welfare implications are developed for both a net exporter and net importer. Consumer surplus, producer surplus, government revenue, and total welfare are compared and contrasted for the EU and the new entrant, both before and after enlargement. Dans le present article, les repercussions qualitatives de l'elargissement de l'UE sur les prix d'intervention, les prelevements variables a l'importation et les paiements de restitution a l'exportation des cereales dans le cadre de la Politique agricole commune (PAC) sont analyses a l'aide d'un modele d'equilibre partiel pour les cultures cerealieres de l'UE. Les repercussions sur le bien-etre sont elaborees dans le cas d'un exportateur net et d'un importateur net. Le surplus des consommateurs, le surplus des producteurs, les recettes publiques et le bien-etre total sont compares pour l'UE et le nouveau venu, et ce, avant et apres l'elargissement de l'UE. Author Affiliation: (1)Associate Professor, Morrison School of Management and Agribusiness, Arizona State University, PRLTA 335N, Mesa, AZ 85212 (corresponding author: phone: 480-727-1566; fax: 480-727-1961; e-mail:troy.schmitz@asu.edu). (2)Graduate Student Researcher, 4904 S. Power Rd., Ste # 103-141, Mesa, AZ 85212 (phone: 510-230-8457; fax: 480-727-1961; e-mail:Christopher.Giese@asu.edu). (3)Professor and Marley Chair, Morrison School of Management and Agribusiness, Arizona State University, PICHO 245C, Mesa, AZ 85212 (phone: 480-727-1242; fax: 480-727-1961; e-mail:clifford.shultz@asu.edu).

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2008.06.012 Byline: Amitabha Bandyopadhyay (a), James K. Kubilus (b), Marsha L. Crochiere (b), Thomas F. Linsenmayer (b), Clifford J. Tabin (a) Keywords: Perichondrium; Periosteum; Gene expression; Appositional growth; Organ culture; TGF-b Abstract: Developing cartilaginous and ossified skeletal anlagen is encapsulated within a membranous sheath of flattened, elongated cells called, respectively, the perichondrium and the periosteum. These periskeletal tissues are organized in distinct morphological layers that have been proposed to support distinct functions. Classical experiments, particularly those using an in vitro organ culture system, demonstrated that these tissues play important roles in regulating the differentiation of the subjacent skeletal elements. However, there has been a lack of molecular markers that would allow analysis of these interactions. To understand the molecular bases for the roles played by the periskeletal tissues, we generated microarrays from perichondrium and periosteum cDNA libraries and used them to compare the gene expression profiles of these two tissues. In situ hybridization analysis of genes identified on the microarrays revealed many unique markers for these tissues and demonstrated that the histologically distinct layers of the perichondrium and periosteum are associated with distinct molecular expression domains. Moreover our marker analysis identified new domains that had not been previously recognized as distinct within these tissues as well as a previously uncharacterized molecular domain along the lateral edges of the adjacent developing cartilage that experimental analysis showed to be dependent upon the perichondrium. Author Affiliation: (a) Department of Genetics, Harvard Medical School, Boston, Massachusetts, USA (b) Department of Anatomy and Cellular Biology, Tufts University School of Medicine, Boston, Massachusetts, USA Article History: Received 26 January 2008; Revised 2 June 2008; Accepted 5 June 2008

The counterclockwise coiling of the intestines is initiated by a leftward tilt of the primitive gut tube, imparted by left-right asymmetries in the architecture of the dorsal mesentery. In silico analysis suggests that this is achieved by synergistic changes in its epithelium and mesenchyme. Within the mesenchymal compartment, cells are more densely packed on the left than on the right. In silico results indicate that this property can result from asymmetries in both extracellular matrix (ECM) and cell:cell adhesion. We find that the dorsal mesentery ECM is indeed left-right asymmetric and moreover that the adhesion molecule N-cadherin is expressed exclusively on the left side. These asymmetries are regulated by the asymmetrically expressed transcription factors Pitx2 and Isl1. Functional studies demonstrate that N-cadherin acts upstream of the changes in the ECM and is both necessary and sufficient to explain the asymmetric packing of the mesenchymal cells. left-right asymmetry | N-cadherin | dorsal mesentery | hyaluronic acid | in silico modeling

Menopause is associated with bone loss and enhanced visceral adiposity. A polyclonal antibody that targets the -subunit of the pituitary hormone follicle-stimulating hormone (Fsh) increases bone mass in mice. Here, we report that this antibody sharply reduces adipose tissue in wild-type mice, phenocopying genetic haploinsufficiency for the Fsh receptor gene Fshr. The antibody also causes profound beiging, increases cellular mitochondrial density, activates brown adipose tissue and enhances thermogenesis. These actions result from the specific binding of the antibody to the -subunit of Fsh to block its action. Our studies uncover opportunities for simultaneously treating obesity and osteoporosis., Author(s): Peng Liu [1]; Yaoting Ji [1, 2]; Tony Yuen [1]; Elizabeth Rendina-Ruedy [3]; Victoria E. DeMambro [3]; Samarth Dhawan [1]; Wahid Abu-Amer [1]; Sudeh Izadmehr [1]; Bin Zhou [4]; [...]

Most local anaesthetics used clinically are relatively hydrophobic molecules that gain access to their blocking site on the sodium channel by diffusing into or through the cell membrane (1). These [...]

Cranes have come to symbolize building construction itself. They perform indispensable services in moving materials and components vertically and horizontally. Used since antiquity, their history is interrelated with the development of new power sources that replaced man and mule, first steam and later internal combustion, diesel, and electric engines. Mobile cranes can be rapidly deployed to lift heavy loads. New models with telescoping booms and all-terrain travel capability, compact urban machines, and even hybrids with tower cranes are beginning to replace the familiar lattice boom truck cranes. Mobile cranes have dominated the North American market, but a cultural change appears to be taking place toward tower cranes for building projects. Tower cranes, common in Europe for decades, are globally gaining in popularity with surging real estate developments. Ideal for dense urban environments and coming with a small footprint, they are available in a growing diversity of sizes and configurations. Sophisticated electronic controls and operator assistance devices are enhancing their safe and productive operation. While cranes occupy a central role on midrise and high-rise building projects, they operate in conjunction with other types of supporting equipment that are an essential part of the overall equipment array on today's industrialized construction sites. CE Database subject headings: Construction management: Construction equipment; Cranes; History.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2007.05.030 Byline: Paul J. Scherz, Edwina McGlinn, Sahar Nissim, Clifford J. Tabin Keywords: Sonic hedgehog; Patterning; Digits; Limb; Morphogen; Temporal gradient Abstract: Sonic hedgehog (Shh) is a key signal in establishing different digit fates along the anterior-posterior axis of the vertebrate limb bud. Although the anterior digits appear to be specified by differential concentrations of Shh in a traditional, morphogen-like response, recent studies have suggested that posterior digits are specified by an extended time of exposure to Shh rather than, or in addition to, a threshold concentration of Shh. This model for digit patterning depends upon continued Shh signaling in the posterior limb through mid-to-late bud stages. We find that cyclopamine, a potent antagonist of Shh signaling, can down-regulate hedgehog target genes in the posterior limb throughout the time Shh is expressed, indicating that continued active Shh signaling indeed takes place. To further explore the relative roles of time and concentration of Shh during limb development, we carried out two additional series of experiments. To test the effect of limiting the time, but not the amount of Shh produced, we treated chick embryos with the hedgehog antagonist cyclopamine at various stages of limb development. We find that short exposures to Shh result in specification of only the most anterior digits and that more posterior digits are specified sequentially with increasing times of uninterrupted Shh activity. To test the effect of limiting the level of Shh produced, but not the time of exposure, we genetically modified Shh production in mice. As previously shown, reducing both the concentration of Shh produced and the duration of Shh exposure results in a loss of posterior digits. We find that maintaining a low level of Shh production throughout the normal time frame of ZPA signaling results in a near complete restoration of the posterior-most digits. These data are consistent with, and lend additional support to, the model that concentration of Shh seen and duration of exposure both contribute to the dose-dependent specification of digit identities, but for the posterior-most digits the temporal component is the more critical parameter. Author Affiliation: Department of Genetics, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA Article History: Received 3 November 2006; Revised 21 May 2007; Accepted 22 May 2007