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Darden PM, Garbe MC, Becton DD, Ochoa ER, Liu D, Brown AW, Curren K, Kelley D, Smith CE. Continuity of care in Arkansas children’s primary care clinics and opportunity for improvement. Am J Med Sci 2023. [DOI: 10.1016/s0002-9629(23)00183-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Becton DD, Garbe MC, Cardenas I, Smith CE, Curren K, Kelley D, Brown AW, Madden CA, Darden PM. Improving access to the medical home in the US and Arkansas: 2019–2020 national survey of children’s health. Am J Med Sci 2023. [DOI: 10.1016/s0002-9629(23)00182-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Garbe MC, Smith CE, Alamarat Z, Curren K, Madden CA, Darden PM. The reasons why adolescents are not vaccinating, changes 2008–2020: national immunization survey – teen. Am J Med Sci 2023. [DOI: 10.1016/s0002-9629(23)00074-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
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Villalón E, Kline RA, Smith CE, Lorson ZC, Osman EY, O'Day S, Murray LM, Lorson CL. AAV9-Stathmin1 gene delivery improves disease phenotype in an intermediate mouse model of spinal muscular atrophy. Hum Mol Genet 2020; 28:3742-3754. [PMID: 31363739 DOI: 10.1093/hmg/ddz188] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 07/12/2019] [Accepted: 07/23/2019] [Indexed: 02/06/2023] Open
Abstract
Spinal muscular atrophy (SMA) is a devastating infantile genetic disorder caused by the loss of survival motor neuron (SMN) protein that leads to premature death due to loss of motor neurons and muscle atrophy. The approval of an antisense oligonucleotide therapy for SMA was an important milestone in SMA research; however, effective next-generation therapeutics will likely require combinatorial SMN-dependent therapeutics and SMN-independent disease modifiers. A recent cross-disease transcriptomic analysis identified Stathmin-1 (STMN1), a tubulin-depolymerizing protein, as a potential disease modifier across different motor neuron diseases, including SMA. Here, we investigated whether viral-based delivery of STMN1 decreased disease severity in a well-characterized SMA mouse model. Intracerebroventricular delivery of scAAV9-STMN1 in SMA mice at P2 significantly increased survival and weight gain compared to untreated SMA mice without elevating Smn levels. scAAV9-STMN1 improved important hallmarks of disease, including motor function, NMJ pathology and motor neuron cell preservation. Furthermore, scAAV9-STMN1 treatment restored microtubule networks and tubulin expression without affecting tubulin stability. Our results show that scAAV9-STMN1 treatment improves SMA pathology possibly by increasing microtubule turnover leading to restored levels of stable microtubules. Overall, these data demonstrate that STMN1 can significantly reduce the SMA phenotype independent of restoring SMN protein and highlight the importance of developing SMN-independent therapeutics for the treatment of SMA.
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Hermo L, Oliveira RL, Smith CE, Au CE, Bergeron JJM. Dark side of the epididymis: tails of sperm maturation. Andrology 2019; 7:566-580. [PMID: 31102346 DOI: 10.1111/andr.12641] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2018] [Revised: 01/25/2019] [Accepted: 03/30/2019] [Indexed: 01/08/2023]
Abstract
BACKGROUND The Hermes body (HB) previously called the cytoplasmic droplet is a focal distension of the flagellar cytoplasm of epididymal spermatozoa consisting mainly of isolated flattened Golgi cisternae. OBJECTIVE To define a functional role for the HB of epididymal spermatozoa. METHODS Isolated fractions of HBs of epididymal spermatozoa were prepared and by quantitative tandem mass spectrometry revealed 1511 proteins. RESULTS The glucose transporter GLUT-3 was the most abundant protein followed by hexokinase 1, which along with the presence of all glycolytic enzymes suggested a role for the HB in glycolysis. Several TMED/p24 Golgi trafficking proteins were abundant with TMED7/p27 and TMED2/p24 defining the identity of the flattened cisternae within the HB as Golgi, along with the known Golgi proteins, GBF1, GOLPH3, Man2α1, and ManIIX. The Golgi trafficking protein TMED7/p27 via small 50-nm vesicles emanating from the Golgi cisternae was proposed to transport GLUT-3 to the plasma membrane for ATP production related to sperm motility. The internal membranes revealed abundant proteins not only of Golgi cisternae, but also of endoplasmic reticulum and endosomes. COPI and COPII coats, clathrin, SNAREs, annexins, atlastins, and GTPases were identified for vesicular trafficking and membrane fusion, in addition to ribosomes, stress proteins for protection, proteasome proteins involved in degradation, and cytoskeletal elements for migration of the HB along the flagellum. The biogenesis of the HB occurring at step 19 spermatids of the testis just prior to their release was uncovered as a key step in germ cell differentiation, where several proteins were expressed, some for the first time. CONCLUSION As epididymal spermatozoa undergo remodeling of their protein makeup through selective degradation of sperm proteins during epididymal transit, then remodeling as a consequence of new protein synthesis is not excluded by our observations.
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Smith CE, Van Rompay MI, Mattei J, Garcia JF, Garcia-Bailo B, Lichtenstein AH, Tucker KL, Ordovás JM. Dietary fat modulation of hepatic lipase variant -514 C/T for lipids: a crossover randomized dietary intervention trial in Caribbean Hispanics. Physiol Genomics 2017; 49:592-600. [PMID: 28939642 DOI: 10.1152/physiolgenomics.00036.2017] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 08/01/2017] [Accepted: 08/01/2017] [Indexed: 11/22/2022] Open
Abstract
The hepatic lipase (LIPC) locus is a well-established determinant of high-density lipoprotein cholesterol (HDL-C) concentrations, an association that is modified by dietary fat in observational studies. Dietary interventions are lacking. We investigated dietary modulation of LIPC rs1800588 (-514 C/T) for lipids and glucose using a randomized crossover design comparing a high-fat Western diet and a low-fat traditional Hispanic diet in individuals of Caribbean Hispanic descent (n = 42, 4 wk/phase). No significant gene-diet interactions were observed for HDL-C. However, differences in dietary response according to LIPC genotype were observed. In major allele carriers (CC/CT), HDL-C (mmol/l) was higher following the Western diet compared with the Hispanic diet: phase 1 (Western: 1.3 ± 0.03; Hispanic: 1.1 ± 0.04; P = 0.0004); phase 2 (Western: 1.4 ± 0.03; Hispanic: 1.2 ± 0.03; P = 0.0003). In contrast, HDL-C in TT individuals did not differ by diet. Only major allele carriers benefited from the higher-fat diet for HDL-C. Secondarily, we explored dietary fat quality and rs1800588 for HDL-C and triglycerides (TG) in a Boston Puerto Rican Health Study (BPRHS) subset matched for diabetes and obesity status (subset n = 384). In the BPRHS, saturated fat was unfavorably associated with HDL-C and TG in rs1800588 TT carriers. LIPC rs1800588 appears to modify plasma lipids in the context of dietary fat. This new evidence of genetic modulation of dietary responses may inform optimal and personalized dietary fat advice and reinforces the importance of studying genetic markers in diet and cardiometabolic health.
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Abstract
Purpose of review The goal of this review is to provide an update on the use of mindfulness meditation for the treatment of insomnia, including conceptual models and empirical evidence from randomized controlled trials. Recent findings A metacognitive model of insomnia has been proposed as a conceptual model to explain the application of mindfulness principles for reducing insomnia-related arousal. Furthermore, the evidence base for mindfulness-based therapies has grown with the results of several randomized controlled trials published in the past three years. Treatment effects appear to be strongest on self-report measures compared to objective measures of sleep. Summary Treatment programs featuring mindfulness meditation appear to be viable treatment options for people with insomnia. Further research is needed to determine who is likely to benefit from mindfulness-based therapies and how these interventions work. Additionally, further work is needed to resolve issues related to the delivery and implementation of mindfulness-based therapies.
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Turner AD, Smith CE, Ong JC. 0757 PURPOSE IN LIFE AND SLEEP DISTURBANCE IN OLDER ADULTS. Sleep 2017. [DOI: 10.1093/sleepj/zsx050.756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Ma Y, Tucker KL, Smith CE, Lee YC, Huang T, Richardson K, Parnell LD, Lai CQ, Young KL, Justice AE, Shao Y, North KE, Ordovás JM. Lipoprotein lipase variants interact with polyunsaturated fatty acids for obesity traits in women: replication in two populations. Nutr Metab Cardiovasc Dis 2014; 24:1323-1329. [PMID: 25156894 PMCID: PMC4356006 DOI: 10.1016/j.numecd.2014.07.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Accepted: 07/04/2014] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND AIMS Lipoprotein lipase (LPL) is a candidate gene for obesity based on its role in triglyceride hydrolysis and the partitioning of fatty acids towards storage or oxidation. Whether dietary fatty acids modify LPL associated obesity risk is unknown. METHODS AND RESULTS We examined five single nucleotide polymorphisms (SNPs) (rs320, rs2083637, rs17411031, rs13702, rs2197089) for potential interaction with dietary fatty acids for obesity traits in 1171 participants (333 men and 838 women, aged 45-75 y) of the Boston Puerto Rican Health Study (BPRHS). In women, SNP rs320 interacted with dietary polyunsaturated fatty acids (PUFA) for body mass index (BMI) (P = 0.002) and waist circumference (WC) (P = 0.001) respectively. Higher intake of PUFA was associated with lower BMI and WC in homozygotes of the major allele (TT) (P = 0.01 and 0.005) but not in minor allele carriers (TG and GG). These interactions were replicated in an independent population, African American women of the Atherosclerosis Risk in Communities (ARIC) study (n = 1334). CONCLUSION Dietary PUFA modulated the association of LPL rs320 with obesity traits in two independent populations. These interactions may be relevant to the dietary management of obesity, particularly in women.
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Smith CE. Agency in smoking cessation: quitters’ strategies for navigating their social networks. Eur J Public Health 2014. [DOI: 10.1093/eurpub/cku163.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Corkery MB, Edgar KL, Smith CE. A survey of physical therapists' clinical practice patterns and adherence to clinical guidelines in the management of patients with whiplash associated disorders (WAD). J Man Manip Ther 2014; 22:75-89. [PMID: 24976750 PMCID: PMC4017798 DOI: 10.1179/2042618613y.0000000048] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
OBJECTIVES To explore the clinical practice of physical therapists and examine adherence to clinical guidelines for treating patients with whiplash associated disorders (WAD). METHODS A cross-sectional electronic survey was sent to 1484 licensed physical therapists from the Orthopedic Section of the American Physical Therapy Association and the American Academy of Orthopedic Manual Physical Therapists. The survey included demographic data and two clinical vignettes describing patients with acute and chronic WAD. The chi-square test was used to analyze responses. RESULTS There were 291(19.6%) responses to the survey. Of those, 237 (81.4%) provided data for vignette 1 and 204 (70.1%) for vignette 2. One hundred and eighty (76.6%) respondents reported familiarity with evidence-based or clinical practice guidelines for treating patients with WAD. Of those, 71.5% (n = 128) indicated that they followed them more than 50% of the time. Therapists with an advanced certification were more likely to be familiar with clinical guidelines than those who were not certified (P<0.01). Responses indicated overall adherence to guidelines; however, there was a low utilization of quantitative sensory assessment, screening for psychological distress and some outcome measures. Significant differences in clinical practice (P<0.01) were found between therapists who were and were not familiar with guidelines and those with and without an advanced certification. DISCUSSION Advanced certification and knowledge of guidelines appeared to play a role in the clinical practice of physical therapists treating patients with WAD. Further research is needed to explore factors affecting knowledge translation from research to clinical practice and to evaluate the outcomes of patients with WAD when clinical guidelines are applied in practice.
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Schmitz JE, Teepe JD, Hu Y, Smith CE, Fajardo RJ, Chun YHP. Estimating mineral changes in enamel formation by ashing/BSE and microCT. J Dent Res 2014; 93:256-62. [PMID: 24470541 DOI: 10.1177/0022034513520548] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Enamel formation produces the most highly mineralized tissue in the human body. The growth of enamel crystallites is assisted by enamel proteins and proteinases. As enamel formation progresses from secretory to maturation stages, the composition of the matrix with its mineral and non-mineral components dynamically changes in an inverse fashion. We hypothesized that appropriately calibrated micro-computed tomography (µCT) technology is suitable to estimate the mineral content (weight and/or density) and volume comparable in accuracy with that for directly weighed and sectioned enamel. Different sets of mouse mandibular incisors of C57BL/6 mice were used for dissections and µCT reconstructions. Calibration phantoms corresponding to the range of enamel mineral densities were used. Secretory-stage enamel contained little mineral and was consequently too poor in contrast for enamel volumes to be accurately estimated by µCT. Maturation-stage enamel, however, showed remarkable correspondence for total mineral content per volume where comparisons were possible between and among the different analytical techniques used. The main advantages of the µCT approach are that it is non-destructive, time-efficient, and can monitor changes in mineral content of the most mature enamel, which is too physically hard to dissect away from the tooth.
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Frazier-Wood AC, Kabagambe EK, Wojczynski MK, Borecki IB, Tiwari HK, Smith CE, Ordovas JM, Arnett DK. The association between LRP-1 variants and chylomicron uptake after a high fat meal. Nutr Metab Cardiovasc Dis 2013; 23:1154-1158. [PMID: 23484911 PMCID: PMC3686991 DOI: 10.1016/j.numecd.2012.12.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Revised: 12/19/2012] [Accepted: 12/27/2012] [Indexed: 11/22/2022]
Abstract
BACKGROUND AND AIMS In vitro studies suggest that low density lipoprotein receptor-related protein 1 (LRP1) plays a role in the secondary uptake of chylomicrons. In addition, in vivo studies using LRP-1 knockout mice show these animals exhibit delayed chylomicron clearance. Whether this is true in humans is unknown. We aimed to determine whether genetic variants in LRP-1 are associated with postprandial chylomicron uptake in humans given an oral fat challenge. METHODS AND RESULTS As many as 817 men and women (mean age +/- standard deviation = 48.4 +/- 16.4 years) forming the study population for the Genetics of Lipid Lowering Drugs Network (GOLDN) study ingested an oral fat load of 700 kilocalories per m² of body surface area at 83% fat, after an 8-h fast. Chylomicrons were measured by nuclear resonance spectroscopy (NMR) at fasting, and 3.5 and 6 h after the meal. 26 Single nucleotide polymorphisms (SNPs) in the LRP-1 gene were genotyped on the Affymetrix 6.0 array. Chylomicrons were, as expected, zero at fasting. Mixed linear models adjusted for age, sex, study site and pedigree tested for associations between LRP-1 SNPs and changes in chylomicron concentrations 3.5-6 h. A gene-based test across all 26 SNPs was conducted which corrected for the linkage disequilibrium (LD) between SNPs. 11 LRP-1 SNPs were significantly associated with the change in chylomicron concentration correction for multiple testing (Q < 0.05). The subsequent gene-based test, was also significant (P = 0.01). CONCLUSION These results require replication but strongly indicate the role of LRP1 in postprandial lipoprotein uptake and/or clearance.
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Lyaruu DM, Medina JF, Sarvide S, Bervoets TJM, Everts V, Denbesten P, Smith CE, Bronckers ALJJ. Barrier formation: potential molecular mechanism of enamel fluorosis. J Dent Res 2013; 93:96-102. [PMID: 24170372 DOI: 10.1177/0022034513510944] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Enamel fluorosis is an irreversible structural enamel defect following exposure to supraoptimal levels of fluoride during amelogenesis. We hypothesized that fluorosis is associated with excess release of protons during formation of hypermineralized lines in the mineralizing enamel matrix. We tested this concept by analyzing fluorotic enamel defects in wild-type mice and mice deficient in anion exchanger-2a,b (Ae2a,b), a transmembrane protein in maturation ameloblasts that exchanges extracellular Cl(-) for bicarbonate. Defects were more pronounced in fluorotic Ae2a,b (-/-) mice than in fluorotic heterozygous or wild-type mice. Phenotypes included a hypermineralized surface, extensive subsurface hypomineralization, and multiple hypermineralized lines in deeper enamel. Mineral content decreased in all fluoride-exposed and Ae2a,b(-/-) mice and was strongly correlated with Cl(-). Exposure of enamel surfaces underlying maturation-stage ameloblasts to pH indicator dyes suggested the presence of diffusion barriers in fluorotic enamel. These results support the concept that fluoride stimulates hypermineralization at the mineralization front. This causes increased release of protons, which ameloblasts respond to by secreting more bicarbonates at the expense of Cl(-) levels in enamel. The fluoride-induced hypermineralized lines may form barriers that impede diffusion of proteins and mineral ions into the subsurface layers, thereby delaying biomineralization and causing retention of enamel matrix proteins.
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Lacruz RS, Smith CE, Kurtz I, Hubbard MJ, Paine ML. New paradigms on the transport functions of maturation-stage ameloblasts. J Dent Res 2012; 92:122-9. [PMID: 23242231 DOI: 10.1177/0022034512470954] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Fully matured dental enamel is an architecturally and mechanically complex hydroxyapatite-based bioceramic devoid of most of the organic material that was essential in its making. Enamel formation is a staged process principally involving secretory and maturation stages, each associated with major changes in gene expression and cellular function. Cellular activities that define the maturation stage of amelogenesis include ion (e.g., calcium and phosphate) transport and storage, control of intracellular and extracellular pH (e.g., bicarbonate and hydrogen ion movements), and endocytosis. Recent studies on rodent amelogenesis have identified a multitude of gene products that appear to be linked to these cellular activities. This review describes the main cellular activities of these genes during the maturation stage of amelogenesis.
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Bartlett JD, Smith CE. Modulation of cell-cell junctional complexes by matrix metalloproteinases. J Dent Res 2012; 92:10-7. [PMID: 23053846 DOI: 10.1177/0022034512463397] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The ameloblast cell layer of the enamel organ is in contact with the forming enamel as it develops into the hardest substance in the body. Ameloblasts move in groups that slide by one another as the enamel layer thickens. Each ameloblast is responsible for the formation of one enamel rod, and the rods are the mineralized trail that moving ameloblasts leave behind. Matrix metalloproteinases (MMPs) facilitate cell movement in various tissues during development, and in this review we suggest that the tooth-specific MMP, enamelysin (MMP20), facilitates ameloblast movements during enamel development. Mmp20 null mice have thin brittle enamel with disrupted rod patterns that easily abrades from the underlying dentin. Strikingly, the Mmp20 null mouse enamel organ morphology is noticeably dysplastic during late-stage development, when MMP20 is no longer expressed. We suggest that in addition to its role of cleaving enamel matrix proteins, MMP20 also cleaves junctional complexes present on ameloblasts to foster the cell movement necessary for formation of the decussating enamel rod pattern. Therefore, inactivation of MMP20 would result in tight ameloblast cell-cell attachments that may cause maturation-stage enamel organ dysplasia. The tight ameloblast attachments would also preclude the ameloblast movement necessary to form decussating enamel rod patterns.
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Smith CE, Arnett DK, Corella D, Tsai MY, Lai CQ, Parnell LD, Lee YC, Ordovás JM. Perilipin polymorphism interacts with saturated fat and carbohydrates to modulate insulin resistance. Nutr Metab Cardiovasc Dis 2012; 22:449-455. [PMID: 21193293 PMCID: PMC3117106 DOI: 10.1016/j.numecd.2010.09.003] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2010] [Revised: 08/20/2010] [Accepted: 09/01/2010] [Indexed: 10/18/2022]
Abstract
BACKGROUND AND AIMS Macronutrient intakes and genetic variants have been shown to interact to alter insulin resistance, but replications of gene-nutrient interactions across independent populations are rare, despite their critical importance in establishing credibility. We aimed to investigate a previously demonstrated saturated fat and carbohydrate interaction for insulin resistance for perilipin (PLIN1), a regulator of adipocyte metabolism. METHODS AND RESULTS We investigated the previously shown interaction for PLIN1 11482G > A (rs894160) on insulin resistance in US men (n = 462) and women (n = 508) (mean ± SD, 49 ± 16 years). In multivariable linear regression models, we found an interaction (P < 0.05) between the ratio of saturated fat to carbohydrate intake as a continuous variable and PLIN1 11482G > A for HOMA-IR (homeostasis model assessment of insulin resistance) in women. For carriers of the minor allele but not for non-carriers, as the ratio of saturated fat to carbohydrate intake increased, predicted HOMA-IR increased (P = 0.002). By dichotomizing the ratio of saturated fat to carbohydrate intake into high and low, we found significant interaction terms for insulin and HOMA-IR (P < 0.05). When the ratio of saturated fat to carbohydrate was high, insulin and HOMA-IR were higher in minor allele carriers (P = 0.004 and P = 0.003, respectively), but did not differ when the ratio was low. Similar patterns or trends were observed when saturated fat and carbohydrate were dichotomized into high and low as individual macronutrients. CONCLUSIONS Replication of the previously reported interaction between macronutrient intakes and PLIN1 genotype for insulin resistance reinforces the potential usefulness of applying genotype information in the dietary management of insulin resistance.
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Orava J, Greer AL, Gholipour B, Hewak DW, Smith CE. Characterization of supercooled liquid Ge2Sb2Te5 and its crystallization by ultrafast-heating calorimetry. NATURE MATERIALS 2012; 11:279-83. [PMID: 22426461 DOI: 10.1038/nmat3275] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2011] [Accepted: 02/09/2012] [Indexed: 05/09/2023]
Abstract
Differential scanning calorimetry (DSC) is widely used to study the stability of amorphous solids, characterizing the kinetics of crystallization close to the glass-transition temperature T(g). We apply ultrafast DSC to the phase-change material Ge(2)Sb(2)Te(5) (GST) and show that if the range of heating rates is extended to more than 10(4) K s(-1), the analysis can cover a wider temperature range, up to the point where the crystal growth rate approaches its maximum. The growth rates that can be characterized are some four orders of magnitude higher than in conventional DSC, reaching values relevant for the application of GST as a data-storage medium. The kinetic coefficient for crystal growth has a strongly non-Arrhenius temperature dependence, revealing that supercooled liquid GST has a high fragility. Near T(g) there is evidence for decoupling of the crystal-growth kinetics from viscous flow, matching the behaviour for a fragile liquid suggested by studies on oxide and organic systems.
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Garaulet M, Esteban Tardido A, Lee YC, Smith CE, Parnell LD, Ordovás JM. SIRT1 and CLOCK 3111T> C combined genotype is associated with evening preference and weight loss resistance in a behavioral therapy treatment for obesity. Int J Obes (Lond) 2012; 36:1436-41. [PMID: 22310473 DOI: 10.1038/ijo.2011.270] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND A new negative feedback loop has been proposed, which suggests connections between the circadian clock and SIRTUIN1 (SIRT1)-dependent functions associated with cell survival, development and metabolism. OBJECTIVE To develop a SIRT1 and circadian locomotor output cycles kaput (CLOCK) combined genotype and to assess its associations with the chronotype of subjects and their potential resistance to weight loss in a behavioral treatment for obesity based on a Mediterranean diet. DESIGN Overweight /obese subjects (n=1465), aged 20-65 years, who attended outpatient obesity clinics, were genotyped for SIRT1 (rs1467568) and CLOCK (3111T>C, rs1801260). Anthropometric, biochemical and dietary-intake variables were analyzed. Effectiveness of the program and weight loss progression during 30 weeks of treatment was assessed. RESULTS We found highly consistent associations between the morning/evening questionnaires across the different genotype categories. Subjects carrying minor alleles at SIRT1 and CLOCK loci (R group) displayed a higher resistance to weight loss and a lower weekly weight loss rate as compared with homozygotes for both major alleles (P group). Significant differences were found across genotypes in weight loss progression during the 30 weeks of treatment (P=0.039). Dietary habits indicated that R carriers had a lower intake of total carbohydrates and monounsaturated fats, and a higher intake of saturated fats than those carrying the intermediate (M) and the P genotype (P=0.02). Plasma ghrelin concentrations were also significantly higher in subjects carrying the R genotype. CONCLUSION Variants of both SIRT1 and CLOCK have an additive effect on resistance to weight loss that could be related to the chronotype of the subject, higher plasma levels of ghrelin and less adherence to Mediterranean diet patterns.
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Corbalán-Tutau MD, Madrid JA, Ordovás JM, Smith CE, Nicolás F, Garaulet M. Differences in daily rhythms of wrist temperature between obese and normal-weight women: associations with metabolic syndrome features. Chronobiol Int 2011; 28:425-33. [PMID: 21721858 DOI: 10.3109/07420528.2011.574766] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The circadian rhythm of core body temperature is associated with widespread physiological effects. However, studies with other more practical temperature measures, such as wrist (WT) and proximal temperatures, are still scarce. The aim of this study was to investigate whether obesity is associated with differences in mean WT values or in its daily rhythmicity patterns. Daily patterns of cortisol, melatonin, and different metabolic syndrome (MetS) features were also analyzed in an attempt to clarify the potential association between chronodisruption and MetS. The study was conducted on 20 normal-weight women (age: 38 ± 11 yrs and BMI: 22 ± 2.6 kg/m(2)) and 50 obese women (age: 42 ± 10 yrs and BMI: 33.5 ± 3.2 kg/m(2)) (mean ± SEM). Skin temperature was measured over a 3-day period every 10 min with the "Thermochron iButton." Rhythmic parameters were obtained using an integrated package for time-series analysis, "Circadianware." Obese women displayed significantly lower mean WT (34.1°C ± 0.3°C) with a more flattened 24-h pattern, a lower-quality rhythm, and a higher intraday variability (IV). Particularly interesting were the marked differences between obese and normal-weight women in the secondary WT peak in the postprandial period (second-harmonic power [P2]), considered as a marker of chronodisruption and of metabolic alterations. WT rhythmicity characteristics were related to MetS features, obesity-related proteins, and circadian markers, such as melatonin. In summary, obese women displayed a lower-quality WT daily rhythm with a more flattened pattern (particularly in the postprandial period) and increased IV, which suggests a greater fragmentation of the rest/activity rhythm compared to normal-weight women. These 24-h changes were associated with higher MetS risk.
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Lacruz RS, Smith CE, Smith SM, Hu P, Bringas P, Sahin-Tóth M, Moradian-Oldak J, Paine ML. Chymotrypsin C (caldecrin) is associated with enamel development. J Dent Res 2011; 90:1228-33. [PMID: 21828354 DOI: 10.1177/0022034511418231] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Two main proteases cleave enamel extracellular matrix proteins during amelogenesis. Matrix metalloprotease-20 (Mmp20) is the predominant enzyme expressed during the secretory stage, while kallikrein-related peptidase-4 (Klk4) is predominantly expressed during maturation. Mutations to both Mmp20 and Klk4 result in abnormal enamel phenotypes. During a recent whole-genome microarray analysis of rat incisor enamel organ cells derived from the secretory and maturation stages of amelogenesis, the serine protease chymotrypsin C (caldecrin, Ctrc) was identified as significantly up-regulated (> 11-fold) during enamel maturation. Prior reports indicate that Ctrc expression is pancreas-specific, albeit low levels were also noted in brain. We here report on the expression of Ctrc in the enamel organ. Quantitative PCR (qPCR) and Western blot analysis were used to confirm the expression of Ctrc in the developing enamel organ. The expression profile of Ctrc is similar to that of Klk4, increasing markedly during the maturation stage relative to the secretory stage, although levels of Ctrc mRNA are lower than for Klk4. The discovery of a new serine protease possibly involved in enamel development has important implications for our understanding of the factors that regulate enamel biomineralization.
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Junyent M, Parnell LD, Lai CQ, Arnett DK, Tsai MY, Kabagambe EK, Straka RJ, Province M, An P, Smith CE, Lee YC, Borecki I, Ordovás JM. ADAM17_i33708A>G polymorphism interacts with dietary n-6 polyunsaturated fatty acids to modulate obesity risk in the Genetics of Lipid Lowering Drugs and Diet Network study. Nutr Metab Cardiovasc Dis 2010; 20:698-705. [PMID: 19819120 PMCID: PMC4361226 DOI: 10.1016/j.numecd.2009.06.011] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Revised: 06/20/2009] [Accepted: 06/25/2009] [Indexed: 11/17/2022]
Abstract
BACKGROUND AND AIMS The disintegrin and metalloproteinase ADAM17, also known as tumor necrosis factor alpha converting enzyme, is expressed in adipocytes. Importantly, elevated levels of ADAM17 expression have been linked to obesity and insulin resistance. Therefore, the aim of this study was to evaluate the association of six ADAM17 single nucleotide polymorphisms (SNPs) (m1254A>G, i14121C>A, i33708A>G, i48827A>C, i53440C>T, and i62781G>T) with insulin-resistance phenotypes and obesity risk, and their potential interactions with dietary polyunsaturated fatty acids (PUFA). METHODS AND RESULTS ADAM17 SNPs were genotyped in 936 subjects (448 men/488 women) who participated in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) study. Anthropometrical and biochemical measurements were determined by standard procedures. PUFA intake was estimated using a validated questionnaire. G allele carriers at the ADAM17_m1254A>G polymorphism exhibited significantly higher risk of obesity (P=0.003), were shorter (P=0.017), had higher insulin (P=0.016), and lower HDL-C concentrations (P=0.027) than AA subjects. For the ADAM17_i33708A>G SNP, homozygotes for the A allele displayed higher risk of obesity (P=0.001), were heavier (P=0.011), had higher BMI (P=0.005), and higher waist measurements (P=0.023) than GG subjects. A significant gene-diet interaction was found (P=0.030), in which the deleterious association of the i33708A allele with obesity was observed in subjects with low intakes from (n-6) PUFA (P<0.001), whereas no differences in obesity risk were seen among subjects with high (n-6) PUFA intake (P>0.5) CONCLUSION These findings support that ADAM17 (m1254A>G and i33708A>G) SNPs may contribute to obesity risk. For the ADAM17_i33708A>G SNP, this risk may be further modulated by (n-6) PUFA intake.
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Tye CE, Sharma R, Smith CE, Bartlett JD. Altered ion-responsive gene expression in Mmp20 null mice. J Dent Res 2010; 89:1421-6. [PMID: 20929715 DOI: 10.1177/0022034510384625] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
During enamel maturation, hydroxyapatite crystallites expand in volume, releasing protons that acidify the developing enamel. This acidity is neutralized by the buffering activity of carbonic anhydrases and ion transporters. Less hydroxyapatite forms in matrix metalloproteinase-20 null (Mmp20(-/-)) mouse incisors, because enamel thickness is reduced by approximately 50%. We therefore asked if ion regulation was altered in Mmp20(-/-) mouse enamel. Staining of wild-type and Mmp20(-/-) incisors with pH indicators demonstrated that wild-type mice had pronounced changes in enamel pH as development progressed. These pH changes were greatly attenuated in Mmp20(-/-) mice. Expression of 4 ion-regulatory genes (Atp2b4, Slc4a2, Car6, Cftr) was significantly decreased in enamel organs from Mmp20(-/-) mice. Notably, expression of secreted carbonic anhydrase (Car6) was reduced to almost undetectable levels in the null enamel organ. In contrast, Odam and Klk4 expression was unaffected. We concluded that a feedback mechanism regulates ion-responsive gene expression during enamel development.
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Junyent M, Tucker KL, Smith CE, Lane JM, Mattei J, Lai CQ, Parnell LD, Ordovas JM. The effects of ABCG5/G8 polymorphisms on HDL-cholesterol concentrations depend on ABCA1 genetic variants in the Boston Puerto Rican Health Study. Nutr Metab Cardiovasc Dis 2010; 20:558-566. [PMID: 19692220 PMCID: PMC4038034 DOI: 10.1016/j.numecd.2009.05.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/24/2009] [Revised: 05/05/2009] [Accepted: 05/06/2009] [Indexed: 11/17/2022]
Abstract
BACKGROUND AND AIMS ATP-binding cassette transporters G5/G8 (ABCG5/G8) are associated with HDL-C concentrations. To assess whether the effect of ABCG5/G8 genetic variants on HDL-C concentrations is dependent on ATP-binding cassette transporters A1 (ABCA1), we studied potential interactions between single nucleotide polymorphisms (SNPs) at ABCG5/G8 (i7892T > C, 5U145A > C, T54CA > G, T400KC > A) and ABCA1 (i27943G > A, i48168G > A, K219RG > A, i125970G > C, 3U8995A > G) genes with HDL-C concentrations. METHODS AND RESULTS ABCG5/G8 and ABCA1 SNPs were genotyped in 788 subjects (228 men and 560 women) who participated in the Boston Puerto Rican Health Study. Biochemical measurements were determined by standard procedures. Genotyping was performed using TaqMan assays according to routine laboratory protocols. Significant gene-gene interactions for HDL-C were found between ABCG8 (5U145A > C, T54CA > G, T400KC > A) SNPs and ABCA1_i48168G > A genetic variant (P = 0.009, P = 0.042 and P = 0.036, respectively), in which carriers of the 5U145C and 54C alleles, and homozygotes for the T400 allele at ABCG8 genetic variants displayed lower HDL-C concentrations than homozygotes for the 5U145A and T54 alleles, and heterozygotes for the 400K allele at ABCG8 SNPs, only if they were also homozygous for the minor allele (A) at the aforementioned ABCA1 SNP. CONCLUSIONS The gene-gene interactions reported in the present study support the hypothesis that the effect of ABCG5/G8 genetic variants on HDL-C concentrations is dependent on ABCA1 expression. Replication of these analyses to further populations, particularly with low HDL-C, is clearly warranted.
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Simmer JP, Papagerakis P, Smith CE, Fisher DC, Rountrey AN, Zheng L, Hu JCC. Regulation of dental enamel shape and hardness. J Dent Res 2010; 89:1024-38. [PMID: 20675598 DOI: 10.1177/0022034510375829] [Citation(s) in RCA: 157] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Epithelial-mesenchymal interactions guide tooth development through its early stages and establish the morphology of the dentin surface upon which enamel will be deposited. Starting with the onset of amelogenesis beneath the future cusp tips, the shape of the enamel layer covering the crown is determined by five growth parameters: the (1) appositional growth rate, (2) duration of appositional growth (at the cusp tip), (3) ameloblast extension rate, (4) duration of ameloblast extension, and (5) spreading rate of appositional termination. Appositional growth occurs at a mineralization front along the ameloblast distal membrane in which amorphous calcium phosphate (ACP) ribbons form and lengthen. The ACP ribbons convert into hydroxyapatite crystallites as the ribbons elongate. Appositional growth involves a secretory cycle that is reflected in a series of incremental lines. A potentially important function of enamel proteins is to ensure alignment of successive mineral increments on the tips of enamel ribbons deposited in the previous cycle, causing the crystallites to lengthen with each cycle. Enamel hardens in a maturation process that involves mineral deposition onto the sides of existing crystallites until they interlock with adjacent crystallites. Neutralization of acidity generated by hydroxyapatite formation is a key part of the mechanism. Here we review the growth parameters that determine the shape of the enamel crown as well as the mechanisms of enamel appositional growth and maturation.
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Runnels HA, Arbuckle JA, Bailey KS, Nicastro PJ, Sun D, Pegg JA, Meyer DM, Evans M, Bono CP, Lie WR, Moffat MA, Casperson GF, Lennard S, Elvin J, Vaughan T, Smith CE, Morton PA. Human monoclonal antibodies to the insulin-like growth factor 1 receptor inhibit receptor activation and tumor growth in preclinical studies. Adv Ther 2010; 27:458-75. [PMID: 20574692 DOI: 10.1007/s12325-010-0026-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2010] [Indexed: 11/28/2022]
Abstract
INTRODUCTION The insulin-like growth factor type 1 (IGF-1) receptor contributes importantly to transformation and survival of tumor cells both in vitro and in vivo, and selective antagonists of the IGF-1 receptor (IGF-1R) activity represent an attractive experimental approach for human cancer therapy. METHODS Using a phage display library, we identified several high-affinity fully human monoclonal antibodies with inhibitory activity against both human and rodent IGF.1Rs. RESULTS These candidate therapeutic antibodies recognized several distinct epitopes and effectively blocked ligand-mediated receptor signal transduction and cellular proliferation in vitro. They also induced IGF-1R downregulation and catabolism following antibody-mediated endocytosis. These antibodies exhibited activity against human, primate, and rodent IGF-1Rs, and dose-dependently inhibited the growth of established human tumors in nude mice. CONCLUSION These fully human antibodies therefore have the potential to provide an effective anti-tumor biological therapy in the human clinical setting.
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Alver B, Back BB, Baker MD, Ballintijn M, Barton DS, Betts RR, Bickley AA, Bindel R, Busza W, Carroll A, Chai Z, Decowski MP, García E, Gburek T, George N, Gulbrandsen K, Halliwell C, Hamblen J, Hauer M, Henderson C, Hofman DJ, Hollis RS, Hołyński R, Holzman B, Iordanova A, Johnson E, Kane JL, Khan N, Kulinich P, Kuo CM, Li W, Lin WT, Loizides C, Manly S, Mignerey AC, Nouicer R, Olszewski A, Pak R, Reed C, Roland C, Roland G, Sagerer J, Seals H, Sedykh I, Smith CE, Stankiewicz MA, Steinberg P, Stephans GSF, Sukhanov A, Tonjes MB, Trzupek A, Vale C, van Nieuwenhuizen GJ, Vaurynovich SS, Verdier R, Veres GI, Walters P, Wenger E, Wolfs FLH, Wosiek B, Woźniak K, Wysłouch B. Event-by-event fluctuations of azimuthal particle anisotropy in Au+Au collisions at square root(sNN) = 200 GeV. PHYSICAL REVIEW LETTERS 2010; 104:142301. [PMID: 20481933 DOI: 10.1103/physrevlett.104.142301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Indexed: 05/29/2023]
Abstract
This Letter presents the first measurement of event-by-event fluctuations of the elliptic flow parameter v(2) in Au+Au collisions at square root(s(NN))=200 GeV as a function of collision centrality. The relative nonstatistical fluctuations of the v(2) parameter are found to be approximately 40%. The results, including contributions from event-by-event elliptic flow fluctuations and from azimuthal correlations that are unrelated to the reaction plane (nonflow correlations), establish an upper limit on the magnitude of underlying elliptic flow fluctuations. This limit is consistent with predictions based on spatial fluctuations of the participating nucleons in the initial nuclear overlap region. These results provide important constraints on models of the initial state and hydrodynamic evolution of relativistic heavy ion collisions.
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Junyent M, Tucker KL, Shen J, Lee YC, Smith CE, Mattei J, Lai CQ, Parnell LD, Ordovas JM. A composite scoring of genotypes discriminates coronary heart disease risk beyond conventional risk factors in the Boston Puerto Rican Health Study. Nutr Metab Cardiovasc Dis 2010; 20:157-164. [PMID: 19501493 PMCID: PMC4031647 DOI: 10.1016/j.numecd.2009.03.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2009] [Revised: 03/10/2009] [Accepted: 03/13/2009] [Indexed: 12/20/2022]
Abstract
BACKGROUND AND AIMS Using a genetic predisposition score (GPS), integrating the additive associations of a set of single nucleotide polymorphisms (SNPs) with CHD, we examined the consequences of the joint presence of a high GPS and conventional risk factors (CRFs). METHODS AND RESULTS We studied 11 SNPs at eight loci in 197 participants with prior CHD and 524 CHD-free subjects from the Boston Puerto Rican Health Study. Each polymorphism contributed 1 unit (high-risk allele homozygous), 0.5 units (heterozygous) and 0 units (low-risk allele homozygous) to the GPS. Odds ratio (OR) of CHD for those at high risk because of GPS (>5) and simultaneous presence of CRFs were estimated, compared with subjects at low risk, for both measurements. The mean score was higher in participants with prior CHD than those CHD-free (P=0.015), and the OR for CHD with a GPS>5 was 2.90 (P<0.001).The joint presence of a high GPS and each CRF was associated with higher risk of CHD. Compared to participants with high GPS, those with low GPS (<or=5) were protected against CHD even if they were smokers (OR=0.44), heavy drinkers (OR=0.43), displayed low physical activity (OR=0.35), had hypertension (OR=0.52) or hyperlipidemia (OR=0.34) (P values ranging from 0.004 to 0.023). CONCLUSION A simple genetic score of 11 polymorphisms may identify those subjects at increased risk of CHD beyond conventional risk factors.
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Alver B, Back BB, Baker MD, Ballintijn M, Barton DS, Betts RR, Bickley AA, Bindel R, Busza W, Carroll A, Chai Z, Chetluru V, Decowski MP, García E, Gburek T, George N, Gulbrandsen K, Halliwell C, Hamblen J, Hauer M, Henderson C, Hofman DJ, Hollis RS, Hołyński R, Holzman B, Iordanova A, Johnson E, Kane JL, Khan N, Kulinich P, Kuo CM, Li W, Lin WT, Loizides C, Manly S, Mignerey AC, Nouicer R, Olszewski A, Pak R, Reed C, Roland C, Roland G, Sagerer J, Seals H, Sedykh I, Smith CE, Stankiewicz MA, Steinberg P, Stephans GSF, Sukhanov A, Tonjes MB, Trzupek A, Vale C, van Nieuwenhuizen GJ, Vaurynovich SS, Verdier R, Veres GI, Walters P, Wenger E, Wolfs FLH, Wosiek B, Woźniak K, Wysłouch B. High transverse momentum triggered correlations over a large pseudorapidity acceptance in Au + Au collisions at square root(s(NN)) = 200 GeV. PHYSICAL REVIEW LETTERS 2010; 104:062301. [PMID: 20366815 DOI: 10.1103/physrevlett.104.062301] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2009] [Revised: 12/24/2009] [Indexed: 05/29/2023]
Abstract
A measurement of two-particle correlations with a high transverse momentum trigger particle (p(T)(trig) > 2.5 GeV/c) is presented for Au+Au collisions at square root(s(NN)) = 200 GeV over the uniquely broad longitudinal acceptance of the PHOBOS detector (-4 < Delta eta < 2). A broadening of the away-side azimuthal correlation compared to elementary collisions is observed at all Delta eta. As in p+p collisions, the near side is characterized by a peak of correlated partners at small angle relative to the trigger particle. However, in central Au+Au collisions an additional correlation extended in Delta eta and known as the "ridge" is found to reach at least |Delta eta| approximately = 4. The ridge yield is largely independent of Delta eta over the measured range, and it decreases towards more peripheral collisions. For the chosen (p(T)(trig) cut, the ridge yield is consistent with zero for events with less than roughly 100 participating nucleons.
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Junyent M, Lee YC, Smith CE, Arnett DK, Tsai MY, Kabagambe EK, Straka RJ, Province M, An P, Lai CQ, Parnell LD, Shen J, Borecki I, Ordovas JM. The effect of a novel intergenic polymorphism (rs11774572) on HDL-cholesterol concentrations depends on TaqIB polymorphism in the cholesterol ester transfer protein gene. Nutr Metab Cardiovasc Dis 2010; 20:34-40. [PMID: 19364639 PMCID: PMC2817943 DOI: 10.1016/j.numecd.2009.02.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2009] [Accepted: 02/11/2009] [Indexed: 12/17/2022]
Abstract
BACKGROUND AND AIMS Several genes have been shown to individually affect plasma lipoprotein metabolism in humans. Studies on gene-gene interactions could offer more insight into how genes affect lipid metabolism and may be useful in predicting lipid concentrations. We tested for gene-gene interactions between TaqIB SNP in the cholesterol ester transfer protein (CETP) and three novel single nucleotide polymorphisms (SNPs), namely rs11774572, rs7819412 and rs6995374 for their effect on metabolic syndrome (MetS) components and related traits. METHODS AND RESULTS The aforementioned SNPs were genotyped in 1002 subjects who participated in the Genetics of Lipid Lowering Drugs and Diet Network (GOLDN) study. Lipids were measured by standard procedures and lipoprotein subfractions, by proton nuclear magnetic resonance spectroscopy. Polymorphism rs11774572 was significantly associated with MetS (P=0.020), mainly driven by the association of the C allele with lower HDL-C (P=0.043) and higher triglycerides (P=0.049) and insulin (P=0.040) concentrations than TT subjects. A significant interaction between SNPs rs11774572 and CETP-TaqIB SNPs was found for HDL-C concentrations (P=0.006) and for HDL (P=0.008) and LDL particle sizes (P=0.009), small LDL (P=0.004), and VLDL concentrations (P=0.021), in which TT homozygotes displayed higher HDL-C concentrations and for HDL and LDL particle sizes, and lower small LDL and VLDL concentrations than C carriers, if they were CETP B2 allele carriers (P values ranging from <0.001 to 0.001). CONCLUSIONS The rs11774572 polymorphism may play a role in the dyslipidemia that characterizes MetS. The interaction between rs11774572 and CETP-TaqIB SNPs on HDL-C concentrations provides some insights into the underlying mechanisms.
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Alver B, Back BB, Baker MD, Ballintijn M, Barton DS, Betts RR, Bindel R, Busza W, Chai Z, Chetluru V, García E, Gburek T, Gulbrandsen K, Hamblen J, Harnarine I, Henderson C, Hofman DJ, Hollis RS, Hołyński R, Holzman B, Iordanova A, Kane JL, Kulinich P, Kuo CM, Li W, Lin WT, Loizides C, Manly S, Mignerey AC, Nouicer R, Olszewski A, Pak R, Reed C, Richardson E, Roland C, Roland G, Sagerer J, Sedykh I, Smith CE, Stankiewicz MA, Steinberg P, Stephans GSF, Sukhanov A, Szostak A, Tonjes MB, Trzupek A, van Nieuwenhuizen GJ, Vaurynovich SS, Verdier R, Veres GI, Walters P, Wenger E, Willhelm D, Wolfs FLH, Wosiek B, Woźniak K, Wyngaardt S, Wysłouch B. System size, energy, and centrality dependence of pseudorapidity distributions of charged particles in relativistic heavy-ion collisions. PHYSICAL REVIEW LETTERS 2009; 102:142301. [PMID: 19392428 DOI: 10.1103/physrevlett.102.142301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2007] [Revised: 08/04/2008] [Indexed: 05/27/2023]
Abstract
We present the first measurements of the pseudorapidity distribution of primary charged particles in Cu+Cu collisions as a function of collision centrality and energy, sqrt[s_{NN}]=22.4, 62.4, and 200 GeV, over a wide range of pseudorapidity, using the PHOBOS detector. A comparison of Cu+Cu and Au+Au results shows that the total number of produced charged particles and the rough shape (height and width) of the pseudorapidity distributions are determined by the number of nucleon participants. More detailed studies reveal that a more precise matching of the shape of the Cu+Cu and Au+Au pseudorapidity distributions over the full range of pseudorapidity occurs for the same N{part}/2A rather than the same N_{part}. In other words, it is the collision geometry rather than just the number of nucleon participants that drives the detailed shape of the pseudorapidity distribution and its centrality dependence at RHIC energies.
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Tsuchiya M, Tye CE, Sharma R, Smith CE, Bartlett JD. XBP1 may determine the size of the ameloblast endoplasmic reticulum. J Dent Res 2008; 87:1058-62. [PMID: 18946015 DOI: 10.1177/154405910808701115] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Ameloblasts progress through defined stages of development as enamel forms on teeth. Pre-secretory ameloblasts give rise to tall columnar secretory ameloblasts that direct the enamel to achieve its full thickness. During the maturation stage, the ameloblasts shorten and direct the enamel to achieve its final hardened form. Here we ask how the volume of selected ameloblast organelles changes (percent volume per ameloblast) as ameloblasts progress through six defined developmental stages. We demonstrate that mitochondria volume peaks during late maturation, indicating that maturation-stage ameloblasts maintain a high level of metabolic activity. Also, the endoplasmic reticulum (ER) volume changes significantly as a function of developmental stage. This prompted us to ask if X-box-binding protein-1 (XBP1) plays a role in regulating ameloblast ER volume, as has been previously demonstrated for secretory acinar cells and for plasma cell differentiation. We demonstrate that Xbp1 expression correlates positively with percent volume of ameloblast ER.
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Cunningham SM, Rush JE, Freeman LM, Brown DJ, Smith CE. Echocardiographic ratio indices in overtly healthy Boxer dogs screened for heart disease. J Vet Intern Med 2008; 22:924-30. [PMID: 18537876 DOI: 10.1111/j.1939-1676.2008.0121.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Boxer dogs are routinely screened by echocardiography to exclude congenital and acquired heart disease. Individuals of a given breed may span a large range of body sizes, potentially invalidating linear regression of M-mode measurements against body weight. Echocardiographic ratio indices (ERIs) provide a novel method of characterizing echocardiographic differences between Boxers and other dog breeds. HYPOTHESIS ERIs obtained from overtly healthy Boxer dogs presented for cardiac screening will be different from ERIs established for normal non-Boxer dogs, and those differences will be unrelated to aortic velocity or systolic blood pressure. ANIMALS Eighty-one Boxers with no outward clinical signs of heart disease were studied. METHODS All dogs were examined by 2-dimensional, M-mode, and Doppler echocardiography. M-mode measurements were used to perform ERI calculations, and the indices in Boxers were compared between Boxers with varying severity of arrhythmia and those of normal non-Boxer dogs. RESULTS Differences in weight-based ERIs, which reflect increased thickness of the left ventricular free wall (LVW) and interventricular septum (IVS) and smaller aortic size, were found in overtly healthy Boxer dogs compared with normal non-Boxer dogs. ERIs of left atrial and LV cavity size in overtly healthy Boxers were not significantly different from those of non-Boxer dogs. CONCLUSIONS AND CLINICAL IMPORTANCE Boxer dogs may have an increased relative thickness of the LVW and IVS that is independent of aortic size, aortic velocity, or arterial blood pressure, and this morphology should be taken into consideration when screening Boxers by echocardiography.
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Smith CE. ROLE OF THE SANITARY PRIVY IN THE CONTROL OF TYPHOID FEVER. Am J Public Health (N Y) 2008; 10:140-1. [PMID: 18010248 DOI: 10.2105/ajph.10.2.140] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Smith CE. Epidemiology of Acute Coccidioidomycosis with Erythema Nodosum ("San Joaquin" or "Valley Fever"). Am J Public Health Nations Health 2008; 30:600-11. [PMID: 18015234 DOI: 10.2105/ajph.30.6.600] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Alver B, Back BB, Baker MD, Ballintijn M, Barton DS, Betts RR, Bickley AA, Bindel R, Busza W, Carroll A, Chai Z, Chetluru V, Decowski MP, García E, Gburek T, George N, Gulbrandsen K, Halliwell C, Hamblen J, Harnarine I, Hauer M, Henderson C, Hofman DJ, Hollis RS, Hołyński R, Holzman B, Iordanova A, Johnson E, Kane JL, Khan N, Kulinich P, Kuo CM, Li W, Lin WT, Loizides C, Manly S, Mignerey AC, Nouicer R, Olszewski A, Pak R, Reed C, Richardson E, Roland C, Roland G, Sagerer J, Seals H, Sedykh I, Smith CE, Stankiewicz MA, Steinberg P, Stephans GSF, Sukhanov A, Szostak A, Tonjes MB, Trzupek A, Vale C, van Nieuwenhuizen GJ, Vaurynovich SS, Verdier R, Veres GI, Walters P, Wenger E, Willhelm D, Wolfs FLH, Wosiek B, Woźniak K, Wyngaardt S, Wysłouch B. System size, energy, pseudorapidity, and centrality dependence of elliptic flow. PHYSICAL REVIEW LETTERS 2007; 98:242302. [PMID: 17677957 DOI: 10.1103/physrevlett.98.242302] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2006] [Indexed: 05/16/2023]
Abstract
This Letter presents measurements of the elliptic flow of charged particles as a function of pseudorapidity and centrality from Cu-Cu collisions at 62.4 and 200 GeV using the PHOBOS detector at the Relativistic Heavy Ion Collider. The elliptic flow in Cu-Cu collisions is found to be significant even for the most central events. For comparison with the Au-Au results, it is found that the detailed way in which the collision geometry (eccentricity) is estimated is of critical importance when scaling out system-size effects. A new form of eccentricity, called the participant eccentricity, is introduced which yields a scaled elliptic flow in the Cu-Cu system that has the same relative magnitude and qualitative features as that in the Au-Au system.
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Back BB, Baker MD, Ballintijn M, Barton DS, Betts RR, Bickley AA, Bindel R, Budzanowski A, Busza W, Carroll A, Chai Z, Decowski MP, García E, Gburek T, George N, Gulbrandsen K, Gushue S, Halliwell C, Hamblen J, Hauer M, Heintzelman GA, Henderson C, Hofman DJ, Hollis RS, Hołyński R, Holzman B, Iordanova A, Johnson E, Kane JL, Katzy J, Khan N, Kucewicz W, Kulinich P, Kuo CM, Lin WT, Manly S, McLeod D, Mignerey AC, Nouicer R, Olszewski A, Pak R, Park IC, Pernegger H, Reed C, Remsberg LP, Reuter M, Roland C, Roland G, Rosenberg L, Sagerer J, Sarin P, Sawicki P, Seals H, Sedykh I, Skulski W, Smith CE, Stankiewicz MA, Steinberg P, Stephans GSF, Sukhanov A, Tang JL, Tonjes MB, Trzupek A, Vale C, van Nieuwenhuizen GJ, Vaurynovich SS, Verdier R, Veres GI, Wenger E, Wolfs FLH, Wosiek B, Woźniak K, Wuosmaa AH, Wysłouch B. Energy dependence of directed flow over a wide range of pseudorapidity in Au + Au collisions at the BNL Relativistic Heavy Ion Collider. PHYSICAL REVIEW LETTERS 2006; 97:012301. [PMID: 16907368 DOI: 10.1103/physrevlett.97.012301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2005] [Indexed: 05/11/2023]
Abstract
We report on measurements of directed flow as a function of pseudorapidity in Au + Au collisions at energies of square root of SNN = 19.6, 62.4, 130 and 200 GeV as measured by the PHOBOS detector at the BNL Relativistic Heavy Ion Collider. These results are particularly valuable because of the extensive, continuous pseudorapidity coverage of the PHOBOS detector. There is no significant indication of structure near midrapidity and the data surprisingly exhibit extended longitudinal scaling similar to that seen for elliptic flow and charged particle pseudorapidity density.
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Alver B, Back BB, Baker MD, Ballintijn M, Barton DS, Betts RR, Bindel R, Busza W, Chai Z, Chetluru V, García E, Gburek T, Gulbrandsen K, Hamblen J, Harnarine I, Henderson C, Hofman DJ, Hollis RS, Hołyński R, Holzman B, Iordanova A, Kane JL, Kulinich P, Kuo CM, Li W, Lin WT, Loizides C, Manly S, Mignerey AC, Nouicer R, Olszewski A, Pak R, Reed C, Richardson E, Roland C, Roland G, Sagerer J, Sedykh I, Smith CE, Stankiewicz MA, Steinberg P, Stephans GSF, Sukhanov A, Szostak A, Tonjes MB, Trzupek A, van Nieuwenhuizen GJ, Vaurynovich SS, Verdier R, Veres GI, Walters P, Wenger E, Willhelm D, Wolfs FLH, Wosiek B, Woźniak K, Wyngaardt S, Wysłouch B. System size and centrality dependence of charged hadron transverse momentum spectra in Au + Au and Cu + Cu collisions at square root of SNN = 62.4 and 200 GeV. PHYSICAL REVIEW LETTERS 2006; 96:212301. [PMID: 16803231 DOI: 10.1103/physrevlett.96.212301] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2005] [Indexed: 05/10/2023]
Abstract
We present transverse momentum distributions of charged hadrons produced in Cu + Cu collisions at square root of SNN = 62.4 and 200 GeV. The spectra are measured for transverse momenta of 0.25 < pT < 5.0 GeV/c at square root of SNN = 62.4 GeV and 0.25 < pT < 7.0 GeV/c at square root of SNN = 200 GeV, in a pseudorapidity range of 0.2 < eta < 1.4. The nuclear modification factor R(AA) is calculated relative to p + p data at both collision energies as a function of collision centrality. At a given collision energy and fractional cross section, R(AA) is observed to be systematically larger in Cu + Cu collisions compared to Au + Au. However, for the same number of participating nucleons, R(AA) is essentially the same in both systems over the measured range of pT, in spite of the significantly different geometries of the Cu + Cu and Au + Au systems.
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Clark VR, Cobb REB, Hopkins R, Smith CE. Black racial identity as a mediator of cardiovascular reactivity to racism in African-American college students. Ethn Dis 2006; 16:108-13. [PMID: 16599357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/08/2023] Open
Abstract
OBJECTIVES The purpose of the present study was to examine the ability of Black racial identity to mediate cardiovascular reactivity to racism. The Multidimensional Model of Racial Identity (MMRI), which consists of four dimensions, salience, centrality, regard, and ideology was used to define Black racial identity. The subdimensions of ideology are oppressed minority, nationalist, humanist, and assimilationist racial identities. DESIGN AND METHODS Heart rate, cardiac output, stroke volume, and blood pressure were measured in 72 African-American men as they viewed a videotaped scene depicting racial profiling and a neutral scene. We hypothesized that individuals with high levels of Black-oriented identities (centrality, public regard, private regard, oppressed minority, and nationalist) would be less stressed by the racial profiling scenes than those low in these identities. In addition, we predicted that individuals with high levels of non-Black-oriented identities (assimilationist, humanist) would be more stressed by the racial profiling scenes than those with low levels of these identities. RESULTS Private regard, humanist, and assimilationist racial identities were significantly associated with increased cardiovascular reactivity to the scenes. Specifically, private regard significantly predicted cardiac output and stroke volume responses to the scenes. In addition, assimilationist and humanist racial identities were associated with greater blood output and faster heart rates in response to the scenes. CONCLUSIONS Although private regard (Black oriented) and assimilationist and humanist (non- Black oriented) racial identities showed elevated cardiovascular reactivity to the scenes, the underlying mechanisms of these associations may differ.
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Back BB, Baker MD, Ballintijn M, Barton DS, Betts RR, Bickley AA, Bindel R, Budzanowski A, Busza W, Carroll A, Chai Z, Decowski MP, García E, Gburek T, George N, Gulbrandsen K, Gushue S, Halliwell C, Hamblen J, Hauer M, Heintzelman GA, Henderson C, Hofman DJ, Hollis RS, Hołyński R, Holzman B, Iordanova A, Johnson E, Kane JL, Katzy J, Khan N, Kucewicz W, Kulinich P, Kuo CM, Lin WT, Manly S, McLeod D, Mignerey AC, Nouicer R, Olszewski A, Pak R, Park IC, Pernegger H, Reed C, Remsberg LP, Reuter M, Roland C, Roland G, Rosenberg L, Sagerer J, Sarin P, Sawicki P, Seals H, Sedykh I, Skulski W, Smith CE, Stankiewicz MA, Steinberg P, Stephans GSF, Sukhanov A, Tang JL, Tonjes MB, Trzupek A, Vale C, van Nieuwenhuizen GJ, Vaurynovich SS, Verdier R, Veres GI, Wenger E, Wolfs FLH, Wosiek B, Woźniak K, Wuosmaa AH, Wysłouch B. Energy dependence of elliptic flow over a large pseudorapidity range in Au+Au collisions at the BNL relativistic heavy ion collider. PHYSICAL REVIEW LETTERS 2005; 94:122303. [PMID: 15903910 DOI: 10.1103/physrevlett.94.122303] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2004] [Indexed: 05/02/2023]
Abstract
This Letter describes the measurement of the energy dependence of elliptic flow for charged particles in Au+Au collisions using the PHOBOS detector at the Relativistic Heavy Ion Collider. Data taken at collision energies of square root of s(NN)=19.6, 62.4, 130, and 200 GeV are shown over a wide range in pseudorapidity. These results, when plotted as a function of eta(')=|eta|-y(beam), scale with approximate linearity throughout eta('), implying no sharp changes in the dynamics of particle production as a function of pseudorapidity or increasing beam energy.
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Back BB, Baker MD, Ballintijn M, Barton DS, Betts RR, Bickley AA, Bindel R, Busza W, Carroll A, Chai Z, Decowski MP, García E, Gburek T, George N, Gulbrandsen K, Halliwell C, Hamblen J, Hauer M, Henderson C, Hofman DJ, Hollis RS, Hołyński R, Holzman B, Iordanova A, Johnson E, Kane JL, Khan N, Kulinich P, Kuo CM, Lin WT, Manly S, Mignerey AC, Nouicer R, Olszewski A, Pak R, Reed C, Roland C, Roland G, Sagerer J, Seals H, Sedykh I, Smith CE, Stankiewicz MA, Steinberg P, Stephans GSF, Sukhanov A, Tonjes MB, Trzupek A, Vale C, van Nieuwenhuizen GJ, Vaurynovich SS, Verdier R, Veres GI, Wenger E, Wolfs FLH, Wosiek B, Woźniak K, Wysłouch B. Centrality dependence of charged hadron transverse momentum spectra in Au+Au collisions from sqrt[s(NN)]=62.4 to 200 GeV. PHYSICAL REVIEW LETTERS 2005; 94:082304. [PMID: 15783881 DOI: 10.1103/physrevlett.94.082304] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2004] [Indexed: 05/24/2023]
Abstract
We have measured transverse momentum distributions of charged hadrons produced in Au+Au collisions at sqrt[s(NN)]=62.4 GeV. The spectra are presented for transverse momenta 0.25<p(T)<4.5 GeV/c, in a pseudorapidity range of 0.2<eta<1.4. The nuclear modification factor R(AA) is calculated relative to p+p data at the same collision energy as a function of collision centrality. For 2<p(T)<4.5 GeV/c, R(AA) is found to be significantly larger than in Au+Au collisions at sqrt[s(NN)]= 130 and 200 GeV. In contrast to the large change in R(AA), we observe a very similar centrality evolution of the p(T) spectra at sqrt[s(NN)]=62.4 and 200 GeV. The dynamical origin of this surprising factorization of energy and centrality dependence of particle production in heavy-ion collisions remains to be understood.
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Bartlett JD, Beniash E, Lee DH, Smith CE. Decreased mineral content in MMP-20 null mouse enamel is prominent during the maturation stage. J Dent Res 2005; 83:909-13. [PMID: 15557396 DOI: 10.1177/154405910408301204] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
During enamel development, matrix metalloproteinase-20 (MMP-20, enamelysin) is expressed early during the secretory stage as the enamel thickens, and kallikrein-4 (KLK-4, EMSP1) is expressed later during the maturation stage as the enamel hardens. Thus, we investigated whether the physical properties of the secretory-/maturation-stage MMP-20 null enamel were significantly different from those of controls. We demonstrated that although, in relative terms, the weight percent of mature mineral in the MMP-20 null mouse enamel was only 7-16% less than that in controls, overall the enamel mineral was reduced by about 50%, and its hardness was decreased by 37%. Percent mineral content by weight was assessed at 3 different developmental stages. Remarkably, the biggest difference in mineral content between MMP-20 null and controls occurred in the nearly mature enamel, when MMP-20 is normally no longer expressed. This suggests that MMP-20 acts either directly or indirectly to facilitate the removal of maturation-stage enamel proteins.
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Back BB, Baker MD, Ballintijn M, Barton DS, Becker B, Betts RR, Bickley AA, Bindel R, Busza W, Carroll A, Decowski MP, García E, Gburek T, George N, Gulbrandsen K, Gushue S, Halliwell C, Hamblen J, Harrington AS, Henderson C, Hofman DJ, Hollis RS, Hołyński R, Holzman B, Iordanova A, Johnson E, Kane JL, Khan N, Kulinich P, Kuo CM, Lee JW, Lin WT, Manly S, Mignerey AC, Nouicer R, Olszewski A, Pak R, Park IC, Pernegger H, Reed C, Roland C, Roland G, Sagerer J, Sarin P, Sedykh I, Skulski W, Smith CE, Steinberg P, Stephans GSF, Sukhanov A, Tonjes MB, Trzupek A, Vale C, Van Nieuwenhuizen GJ, Verdier R, Veres GI, Wolfs FLH, Wosiek B, Woźniak K, Wysłouch B, Zhang J. Pseudorapidity distribution of charged particles in d+Au collisions at sqrt[sNN]=200 GeV. PHYSICAL REVIEW LETTERS 2004; 93:082301. [PMID: 15447175 DOI: 10.1103/physrevlett.93.082301] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2003] [Indexed: 05/24/2023]
Abstract
The measured pseudorapidity distribution of primary charged particles in minimum-bias d+Au collisions at sqrt[s(NN)]=200 GeV is presented for the first time. This distribution falls off less rapidly in the gold direction as compared to the deuteron direction. The average value of the charged particle pseudorapidity density at midrapidity is <dN(ch)/d eta>|eta|< or =0.6)=9.4+/-0.7(syst) and the integrated primary charged particle multiplicity in the measured region is 82+/-6(syst). Estimates of the total charged particle production, based on extrapolations outside the measured pseudorapidity region, are also presented. The pseudorapidity distribution, normalized to the number of participants in d+Au collisions, is compared to those of Au+Au and p+(-)p systems at the same energy. The d+Au distribution is also compared to the predictions of the parton saturation model, as well as microscopic models.
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Hall T, Wood DC, Smith CE. Preparative and analytical chromatography of pegylated myelopoietin using monolithic media. J Chromatogr A 2004; 1041:87-93. [PMID: 15281257 DOI: 10.1016/j.chroma.2004.04.037] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Monolithic media were compared with Q- and SP-Sepharose high performance chromatography for preparative purification and with Q- and SP-5PW chromatography for analysis of a pegylated form of myelopoietin (MPO), an engineered hematopoietic growth factor. The use of either monolithic or Sepharose based supports for preparative chromatography produced highly purified pegylated MPO with the monolithic media demonstrating peak resolution and repeatability at flow rates of 1 and 5 ml/min resulting in run times as much as five-fold shorter compared to Sepharose separations. The monolithic disks also resulted in 10-fold shorter run times for the analytical chromatography, however, their chromatographic profiles and peak symmetry were not as sharp compared to their Q-5PW and SP-5PW counterparts.
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Back BB, Baker MD, Ballintijn M, Barton DS, Becker B, Betts RR, Bickley AA, Bindel R, Budzanowski A, Busza W, Carroll A, Decowski MP, García E, Gburek T, George N, Gulbrandsen K, Gushue S, Halliwell C, Hamblen J, Harrington AS, Henderson C, Hofman DJ, Hollis RS, Hołyński R, Holzman B, Iordanova A, Johnson E, Kane JL, Khan N, Kulinich P, Kuo CM, Lee JW, Lin WT, Manly S, Mignerey AC, Noell A, Nouicer R, Olszewski A, Pak R, Park IC, Pernegger H, Reed C, Remsberg LP, Roland C, Roland G, Sagerer J, Sarin P, Sawicki P, Sedykh I, Skulski W, Smith CE, Steinberg P, Stephans GSF, Sukhanov A, Teng R, Tonjes MB, Trzupek A, Vale C, van Nieuwenhuizen GJ, Verdier R, Veres GI, Wadsworth B, Wolfs FLH, Wosiek B, Woźniak K, Wuosmaa AH, Wysłouch B, Zhang J. Centrality dependence of charged-hadron transverse-momentum spectra in d+Au collisions at sqrt[s(NN)]=200 GeV. PHYSICAL REVIEW LETTERS 2003; 91:072302. [PMID: 12935007 DOI: 10.1103/physrevlett.91.072302] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2003] [Indexed: 05/24/2023]
Abstract
We have measured transverse momentum distributions of charged hadrons produced in d+Au collisions at sqrt[s(NN)]=200 GeV. The spectra were obtained for transverse momenta 0.25<p(T)<6.0 GeV/c, in a pseudorapidity range of 0.2<eta<1.4 in the deuteron direction. The evolution of the spectra with collision centrality is presented in comparison to p+pmacr; collisions at the same collision energy. With increasing centrality, the yield at high transverse momenta increases more rapidly than the overall particle density, leading to a strong modification of the spectral shape. This change in spectral shape is qualitatively different from observations in Au+Au collisions at the same energy. The results provide important information for discriminating between different models for the suppression of high-p(T) hadrons observed in Au+Au collisions.
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DenBesten PK, Yan Y, Featherstone JDB, Hilton JF, Smith CE, Li W. Effects of fluoride on rat dental enamel matrix proteinases. Arch Oral Biol 2002; 47:763-70. [PMID: 12446183 DOI: 10.1016/s0003-9969(02)00117-6] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Enamel fluorosis is characterised by increased porosity and a delay in the removal of enamel matrix proteins as the enamel matures. Amelogenin is the primary matrix protein in secretory-stage dental enamel. As enamel matures, amelogenins are hydrolysed by a number of enamel proteinases, including matrix metalloproteinase-20 (MMP-20 or enamelysin) and serine proteinase. Here, the effect of ingested fluoride on the relative activity of proteinases in the enamel matrix and the specific effect of fluoride on MMP-20 activity were examined. Proteinase activity relative to total enamel matrix protein was measured by fluorescence assay of enamel matrix dissected from rats given 0, 50, or 100 parts per 10(6) fluoride in their drinking water. To determine the specific effect of fluoride on the activity of MMP-20, the hydrolysis of a full-length recombinant human amelogenin by recombinant MMP-20 (rMMP-20) in the presence of 0, 2, 5, 10 or 100 microM fluoride was compared by sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis (PAGE). In addition, a fluorescent peptide assay was developed to quantify enzyme activity against the tyrosine-rich amelogenin peptide cleavage site. In the late maturation stage, total proteinase activity per unit protein was lower in the fluoride-exposed rats than in the control rats. This in vivo finding indicates that fluoride ingestion can alter the relative amount of active proteinase in mature enamel. Hydrolysis of amelogenin at neutral pH by rMMP-20 was reduced in the presence of 100 microM F. In the peptide assay, rMMP-20 activity was significantly reduced by concentrations of fluoride as low as 2 microM at pH 6, with no significant effect at pH 7.2. These in vitro assays show that micromolar concentrations of fluoride can alter metalloproteinase activity, particularly when the pH is reduced to 6.0. These studies suggest that the effects of fluoride on enamel matrix proteinase secretion or activity could be involved in the aetiology of fluorosis in enamel and other mineralising tissues.
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Smith CE, Kleinbeck SV, Boyle D, Kochinda C, Parker S. Family Caregivers' Motives for Helping Scale derived from motivation-to-help theory. J Nurs Meas 2002; 9:239-57. [PMID: 11881267] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
The literature does not contain a measure of family caregivers' motives for helping provide daily complex home care. Such a measure will permit nurses to assess and provide interventions specific to each caregiver's motivation for helping. The purpose of this study was to apply Batson's empirically derived helping pathway theory to the measurement of caregiver motives for helping and develop a short form that does not add to the burden of caregiving. A Principal Components factor analysis (N = 93) of Family Caregivers' Motives for Helping Scale is used. Criterion-related validity is ascertained using a triangulated, independent validation procedure with qualitative data from a subsample (N = 41). Subsample subjects' interview data were categorized, based on Batson's theoretical pathway definitions, by coders blinded to caregiver Motives for Helping Scale scores. Three of Batson's four helping pathways (reward seeking, altruism, and punishment-avoidance) were extracted during factor analysis. This three-factor solution explained 66.6% of the variance and was confirmed by a 97% agreement between three of Batson's pathways and caregivers' helping motive score. The content analyses of the descriptive interview data also coincide with the 3-factor solution. The scale items representing Batson's fourth helping pathway, distress reaction, were not retained due to cross loading. The Family Caregivers' Motives for Helping Scale accurately measures three of four theoretically derived motivations for helping another. The scale should be reanalyzed in a larger sample of caregivers. Aligning nursing interventions to caregiver motives for helping can provide reinforcement for caregivers and potentially enhance home care outcomes.
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Smith CE, Atchabahian A, Mackinnon SE, Hunter DA. Development of the blood-nerve barrier in neonatal rats. Microsurgery 2002; 21:290-7. [PMID: 11754428 DOI: 10.1002/micr.1055] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The blood-nerve barrier (BNB) is constituted by the perineurium and the endothelium of endoneurial microvessels. We investigated the age at which the vascular component of BNB function is established in the rat and the ultrastructural modifications accompanying changes in permeability. BNB permeability was assessed with injections of Evans blue albumin (EBA) and horseradish peroxidase (HRP) in rats of different ages. Sciatic nerve sections were studied using fluorescence and electron microscopy. Nerves from animals injected with EBA indicated that the BNB is not functional before 13 days of life but that its function is established by 16 days. These results were confirmed by electron microscope examination of nerve sections from animals injected with HRP, which showed clefts between the endothelial cells of endoneurial vessels in young rats. In rats over 18 days, these clefts were occluded by tight junctions, which prevented HRP from leaving the vessel lumen and conferred BNB function. Systematic morphometric analysis of nerves from different age groups allowed the establishment of baseline normal histologic neural development with age.
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Milner SM, Mottar R, Smith CE. The Burn Wheel. Am J Nurs 2001; 101:35-7. [PMID: 11718112 DOI: 10.1097/00000446-200111000-00018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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