Lyon, Elaine; Laver, Thomas; Yu, Ping; Jama, Mohamed; Young, Keith; Zoccoli, Michael; Marlowe, Natalia
2010-01-01
Population screening has been proposed for Fragile X syndrome to identify premutation carrier females and affected newborns. We developed a PCR-based assay capable of quickly detecting the presence or absence of an expanded FMR1 allele with high sensitivity and specificity. This assay combines a triplet repeat primed PCR with high-throughput automated capillary electrophoresis. We evaluated assay performance using archived samples sent for Fragile X diagnostic testing representing a range of Fragile X CGG-repeat expansions. Two hundred five previously genotyped samples were tested with the new assay. Data were analyzed for the presence of a trinucleotide “ladder” extending beyond 55 repeats, which was set as a cut-off to identify expanded FMR1 alleles. We identified expanded FMR1 alleles in 132 samples (59 premutation, 71 full mutation, 2 mosaics) and normal FMR1 alleles in 73 samples. We found 100% concordance with previous results from PCR and Southern blot analyses. In addition, we show feasibility of using this assay with DNA extracted from dried-blood spots. Using a single PCR combined with high-throughput fragment analysis on the automated capillary electrophoresis instrument, we developed a rapid and reproducible PCR-based laboratory assay that meets many of the requirements for a first-tier test for population screening. PMID:20431035
Nailfold capillaroscopic changes in Kindler syndrome.
Dobrev, Hristo P; Vutova, Nina I
2015-11-01
Kindler syndrome (KS), the fourth major type of hereditary epidermolysis bullosa (HEB), is a rare, autosomal recessive disorder characterized by skin fragility and blistering at birth followed by development of marked photosensitivity and progressive poikilodermatous skin changes in later years. We reported here the case of a 54-year-old woman, who fulfills the diagnostic criteria of KS type of HEB, putting accent on the nailfold capillaroscopic changes. Using videocapillaroscopy we observed pronounced alterations in finger nail capillaries including reduction in capillary density, features of neoangiogenesis (architectural derangement, elongated loops, extremely tortuous, bushy or branching capillaries, thin, branching and interconnected capillaries), enlarged and giant capillaries. We consider the changes observed as an adaptive mechanism that compensate the loss of capillaries due to chronic periungual trauma. Further studies with larger number of patients are needed to confirm the significance of capillaroscopy findings for patients with HEB.
New type of capillary for use as ion beam collimator and air-vacuum interface
NASA Astrophysics Data System (ADS)
Stoytschew, V.; Schulte-Borchers, M.; Božičević Mihalića, Iva; Perez, R. D.
2016-08-01
Glass capillaries offer a unique way to combine small diameter ion beam collimation with an air-vacuum interface for ambient pressure ion beam applications. Usually they have an opening diameter of a few microns, limiting the air inflow sufficiently to maintain stable conditions on the vacuum side. As the glass capillaries generally are quite thin and fragile, handling of the capillary in the experiment becomes difficult. They also introduce an X-ray background produced by the capillary wall material, which has to be shielded or subtracted from the data for Particle Induced X-ray Emission (PIXE) applications. To overcome both drawbacks, a new type of conical glass capillary has been developed. It has a higher wall thickness eliminating the low energy X-ray background produced by common capillaries and leading to a more robust lens. The results obtained in first tests show, that this new capillary is suitable for ion beam collimation and encourage further work on the capillary production process to provide thick wall capillaries with an outlet diameter in the single digit micro- or even nanometre range.
In situ data collection and structure refinement from microcapillary protein crystallization
Yadav, Maneesh K.; Gerdts, Cory J.; Sanishvili, Ruslan; Smith, Ward W.; Roach, L. Spencer; Ismagilov, Rustem F.; Kuhn, Peter; Stevens, Raymond C.
2007-01-01
In situ X-ray data collection has the potential to eliminate the challenging task of mounting and cryocooling often fragile protein crystals, reducing a major bottleneck in the structure determination process. An apparatus used to grow protein crystals in capillaries and to compare the background X-ray scattering of the components, including thin-walled glass capillaries against Teflon, and various fluorocarbon oils against each other, is described. Using thaumatin as a test case at 1.8 Å resolution, this study demonstrates that high-resolution electron density maps and refined models can be obtained from in situ diffraction of crystals grown in microcapillaries. PMID:17468785
Hanazawa, Toyoyuki; Yonekura, Shuji; Nakamura, Hiroko; Fujikawa, Akira; Okamoto, Yoshitaka
2016-04-01
Lobular capillary hemangiomas (LCHs), also known as pyogenic granulomas, are benign, rapidly growing hemorrhagic lesions that usually develop in the oral or nasal cavities. In adults, LCHs occur in <5% of all pregnant women. A 30-year-old woman presented with a 4-month history of right-sided nasal obstruction and recurrent epistaxis 2 months post-partum. A fragile, pink-red lobulated tumor existed in the anterior portion of the right inferior turbinate; the biopsy revealed a LCH. Although the patient declined surgery using an external approach, treatment with systemic corticosteroids combined with antibiotics resulted in tumor regression and an endoscopic en bloc resection was possible. No recurrence has been noted to date (>1 year after surgery). Pre-operative treatment with systemic corticosteroids combined with antibiotics may be useful to induce tumor regression and to excise the lesion completely with an endoscopic approach. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Ehlers-Danlos syndrome(s) mimicking child abuse: Is there an impact on clinical practice?
Castori, Marco
2015-12-01
Ehlers-Danlos syndrome is a heterogeneous group of heritable connective tissue disorders characterized by increased fragility of various non-ossified tissues. It is usually ascertained due to abnormal skin texture, scarring complications, vascular fragility, or chronic symptoms, such as fatigue and musculoskeletal pain. Sometimes, Ehlers-Danlos syndrome remains undetected until the patient, usually in the pediatric age, shows extensive or severe mucocutaneous injuries after only minor traumas. In this scenario, the misdiagnosis of Ehlers-Danlos syndrome with child abuse is a possibility, as occasionally reported in the literature. Recently, more attention was posed by lay people between the possible association of Ehlers-Danlos syndrome and bone fragility. Literature and personal experience show a strong association between Ehlers-Danlos syndrome, generalized joint hypermobility and reduced bone mass density in older children and adults, especially fertile women. The existence of a true increased risk of fracture in Ehlers-Danlos syndrome is still a matter of debate in children and adults with little and conflicting evidence. In case of suspected child abuse, Ehlers-Danlos syndrome is certainly on the differential for bruising, especially in EDS types with marked cutaneous and capillary involvement. In suspected child abuse cases, careful examination of the index case and her/his extended family is routine, as well as exclusion of other disorders such as osteogenesis imperfecta. The hypothesis of Ehlers-Danlos syndrome as an alternative explanation for infantile fractures remains speculative. © 2015 Wiley Periodicals, Inc.
Sorbitol crystallization-induced aggregation in frozen mAb formulations.
Piedmonte, Deirdre Murphy; Hair, Alison; Baker, Priti; Brych, Lejla; Nagapudi, Karthik; Lin, Hong; Cao, Wenjin; Hershenson, Susan; Ratnaswamy, Gayathri
2015-02-01
Sorbitol crystallization-induced aggregation of mAbs in the frozen state was evaluated. The effect of protein aggregation resulting from sorbitol crystallization was measured as a function of formulation variables such as protein concentration and pH. Long-term studies were performed on both IgG1 and IgG2 mAbs over the protein concentration range of 0.1-120 mg/mL. Protein aggregation was measured by size-exclusion HPLC (SE-HPLC) and further characterized by capillary-electrophoresis SDS. Sorbitol crystallization was monitored and characterized by subambient differential scanning calorimetry and X-ray diffraction. Aggregation due to sorbitol crystallization is inversely proportional to both protein concentration and formulation pH. At high protein concentrations, sorbitol crystallization was suppressed, and minimal aggregation by SE-HPLC resulted, presumably because of self-stabilization of the mAbs. The glass transition temperature (Tg ') and fragility index measurements were made to assess the influence of molecular mobility on the crystallization of sorbitol. Tg ' increased with increasing protein concentration for both mAbs. The fragility index decreased with increasing protein concentration, suggesting that it is increasingly difficult for sorbitol to crystallize at high protein concentrations. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.
The Antivascular Actions of Mild Intensity Ultrasound on a Murine Neoplasm
NASA Astrophysics Data System (ADS)
Wood, Andrew K. W.; Bunte, Ralph M.; Ansaloni, Sara; Lee, William M.-F.; Sehgal, Chandra M.
2006-05-01
This study was aimed at determining whether mild intensity ultrasound affected the fragile and leaky angiogenic blood vessels in a tumor. In 27 mice (C3HV/HeN strain) a subcutaneous melanoma (K173522) was insonated with continuous physiotherapy ultrasound (1 MHz; spatial-average-temporal-average = 2.3 W cm-2). Analyses of contrast enhanced power Doppler observations showed that insonation significantly increased the avascular area in the neoplasm. A linear regression analysis demonstrated that each min of insonation lead to a 25% reduction in tumor vascularity. The predominant acute effect of insonation was an apparently irreparable dilation of the tumor capillaries; liquefactive necrosis of neoplastic cells, related to a secondary ischemia, was a delayed effect.
Grasso, Marina; Boon, Elles M.J.; Filipovic-Sadic, Stela; van Bunderen, Patrick A.; Gennaro, Elena; Cao, Ru; Latham, Gary J.; Hadd, Andrew G.; Coviello, Domenico A.
2015-01-01
Fragile X syndrome and associated disorders are characterized by the number of CGG repeats and methylation status of the FMR1 gene for which Southern blot (SB) historically has been required for analysis. This study describes a simple PCR-only workflow (mPCR) to replace SB analysis, that incorporates novel procedural controls, treatment of the DNA in separate control and methylation-sensitive restriction endonuclease reactions, amplification with labeled primers, and two-color amplicon sizing by capillary electrophoresis. mPCR was evaluated in two independent laboratories with 76 residual clinical samples that represented typical and challenging fragile X alleles in both males and females. mPCR enabled superior size resolution and analytical sensitivity for size and methylation mosaicism compared to SB. Full mutation mosaicism was detected down to 1% in a background of 99% normal allele with 50- to 100-fold less DNA than required for SB. A low level of full mutation mosaicism in one sample was detected using mPCR but not observed using SB. Overall, the sensitivity for detection of full mutation alleles was 100% (95% CI: 89%–100%) with an accuracy of 99% (95% CI: 93%–100%). mPCR analysis of DNA from individuals with Klinefelter and Turner syndromes, and DNA from sperm and blood, were consistent with SB. As such, mPCR enables accurate, sensitive, and standardized methods of FMR1 analysis that can harmonize results across different laboratories. PMID:24177047
PFARRER, CHRISTIANE; EBERT, BRIGITTE; MIGLINO, MARIA ANGELICA; KLISCH, KARL; LEISER, RUDOLF
2001-01-01
Both the fetal and maternal microvasculature of bovine placentomes was examined by scanning electron microscopy of vascular casts. So far the development of the vascular architecture of the bovine placentome in early gestation has only been studied 2-dimensionally due to technical difficulties arising from the fragility of the early placental blood vessels. Repeated experiments led to the selection of the microvascular corrosion casts presented here. The vasculature of the maternal compartment is supplied by large caruncular stalk or spiral arteries, which release short maternal stem arteries. In the 3rd month of gestation, these arteries branch into several arterioles at their base, thus providing the vascular framework for the lower part of the septal walls of the primary crypts. In the 4th month, due to progressive longitudinal growth of the stem arteries, branching into arterioles occurs not only at the base, but over the whole length of the stem arteries. These arterioles supply the capillary complexes of the septa which resemble the major part of the septal vasculature and face the secondary crypts. Further indentation results in the formation of tertiary crypt capillary complexes, encircling the earlier secondary unit. From the 6th month of gestation the architecture resembles the fully developed maternal placenta with stem arteries running directly to the fetal side to branch into 4 to 6 arterioles, which turn back to enter secondary and tertiary septa. Maternal venules, collecting the blood from the capillary bed of secondary and tertiary septa, converge onto stem veins leaving the caruncle via branches of the uterine vein. The fetal part of the placentome is supplied by the cotyledonary arteries, which branch into fetal stem arteries that are the tributary to single villous trees. Over their whole course towards the maternal side, these give off arterioles entering secondary villi. The tertiary or terminal villous vasculature consists of capillaries, which are organised in serial capillary loops. This system is progressively elaborated in the course of gestation. In the 4th month there are only finger-like loops, whereas from the 6th month large fan-like structures can be observed. In early gestation the maternal and fetal blood vessels meet predominantly in a countercurrent fashion, changing to the less efficient crosscurrent exchange when the tertiary unit develops. These results indicate the development of a highly elaborated fetomaternal villous-crypt exchange system, already established in the 1st half of gestation, thus meeting the increasing needs of the fetus. PMID:11430698
Patterns of funding allocation for tuberculosis control in fragile states.
Warsame, A; Patel, P; Checchi, F
2014-01-01
To assess recent (2006-2010) tuberculosis (TB) funding patterns in conflict and non-conflict-affected fragile states to inform global policy. The Creditor Reporting System was analysed for official development assistance funding disbursements towards TB control in 11 conflict-affected states, 17 non-conflict-affected fragile states and 38 comparable non-fragile states. The amounts of funding, funding relative to burden, funding relative to malaria and human immunodeficiency virus (HIV) control, disbursements relative to commitments, sources of funding as well as funding activities were extracted and analysed. Fragile states received on average more per capita for TB control relative to non-fragile states (US0.159 vs. US0.079). However conflict-affected fragile states received on average less per capita than non-conflict-affected states (US0.144 vs. US0.203), despite worse development indicators. Conflict-affected fragile states also received on average only 70% of TB funds already committed. Analysis by burden revealed the least disparity in funding in highest prevalence settings. Analysis of funding activities suggests increasing importance of TB-HIV integration, multidrug-resistant TB and research in both fragile and non-fragile states. Relative to non-conflict-affected fragile states, conflict-affected fragile states received approximately two thirds the per capita funding for TB. This study revealed disparities in TB control funding between fragile and non-fragile as well as between conflict and non-conflict-affected fragile states. Findings suggest possible avenues for improving the allocation of global TB funding.
Avian embryonic development in hyperdynamic environments
NASA Technical Reports Server (NTRS)
Abbott, U. K.; Smith, A. H.
1983-01-01
Embryos which developed for 24 hours in the oviduct of hens maintained at 2 G and which were subsequently incubated at Earth gravity had a 14% reduction in hatchability. Increased mortality during the first 4 days, and an increase in embryonic abnormalities were of the types usually found during the first mortality peak (2-3 days). Embryos in eggs that were produced at Earth gravity and continued their development on the centrifuge at fields of 2 G or less did not appear to be greatly affected by the treatment. At 4 G, 91% of the embryos died, mostly on the first and second days of incubation. Abnormalities prominent in the centrifuged eggs include: (a) a failure of the primitive streak to develop; (b) interference with the development of the axial skeleton; (c) multiple hemorrhages, mostly petechial which is consistent with capillary fragility; and (d) retardation of embryo growth, possibly caused by an interference with gaseous diffusion, the result of an acceleration-induced increase in gas density in the centrifuging incubator.
Spherocytosis - osmotic fragility; Thalassemia - osmotic fragility ... done to detect conditions called hereditary spherocytosis and thalassemia . Hereditary spherocytosis makes red blood cells more fragile ...
Fragility Extraordinaire: Unsolved Mysteries of Chromosome Fragile Sites.
Feng, Wenyi; Chakraborty, Arijita
2017-01-01
Chromosome fragile sites are a fascinating cytogenetic phenomenon now widely implicated in a slew of human diseases ranging from neurological disorders to cancer. Yet, the paths leading to these revelations were far from direct, and the number of fragile sites that have been molecularly cloned with known disease-associated genes remains modest. Moreover, as more fragile sites were being discovered, research interests in some of the earliest discovered fragile sites ebbed away, leaving a number of unsolved mysteries in chromosome biology. In this review we attempt to recount some of the early discoveries of fragile sites and highlight those phenomena that have eluded intense scrutiny but remain extremely relevant in our understanding of the mechanisms of chromosome fragility. We then survey the literature for disease association for a comprehensive list of fragile sites. We also review recent studies addressing the underlying cause of chromosome fragility while highlighting some ongoing debates. We report an observed enrichment for R-loop forming sequences in fragile site-associated genes than genomic average. Finally, we will leave the reader with some lingering questions to provoke discussion and inspire further scientific inquiries.
Improved Iris Recognition through Fusion of Hamming Distance and Fragile Bit Distance.
Hollingsworth, Karen P; Bowyer, Kevin W; Flynn, Patrick J
2011-12-01
The most common iris biometric algorithm represents the texture of an iris using a binary iris code. Not all bits in an iris code are equally consistent. A bit is deemed fragile if its value changes across iris codes created from different images of the same iris. Previous research has shown that iris recognition performance can be improved by masking these fragile bits. Rather than ignoring fragile bits completely, we consider what beneficial information can be obtained from the fragile bits. We find that the locations of fragile bits tend to be consistent across different iris codes of the same eye. We present a metric, called the fragile bit distance, which quantitatively measures the coincidence of the fragile bit patterns in two iris codes. We find that score fusion of fragile bit distance and Hamming distance works better for recognition than Hamming distance alone. To our knowledge, this is the first and only work to use the coincidence of fragile bit locations to improve the accuracy of matches.
Psychiatric and autistic comorbidity in fragile X syndrome across ages.
Gabis, Lidia V; Baruch, Yael Kesner; Jokel, Ariela; Raz, Raanan
2011-08-01
Fragile X syndrome is caused by CGG trinucleotide repeat expansion within the fragile X mental retardation 1 gene, when repeat number exceeds 200. The typical psychiatric profile of fragile X syndrome patients includes cognitive and behavioral deficits, psychiatric comorbidity, and autistic characteristics. Specific psychiatric features have not yet been clarified, specifically in relationship to age and genetic characteristics. The objective of this study was to characterize psychiatric comorbidities in subjects with fragile X syndrome at different ages. Subjects with fragile X syndrome and their unaffected siblings were recruited and their parents filled out functional-behavioral and psychiatric comorbidities questionnaires. Adolescents with fragile X syndrome showed decreased prevalence of functional-behavioral deficits. Incidence and severity of most psychiatric comorbidities were lower in older subjects. Incidence of generalized anxiety disorder increased with age in the fragile X syndrome group. The typical profile of patients with fragile X syndrome changes with age. Unaffected siblings exhibit anxiety and motor tics.
Behavioral Phenotype of Fragile X Syndrome in Adolescence and Adulthood
Smith, Leann E.; Barker, Erin T.; Seltzer, Marsha Mailick; Abbeduto, Leonard; Greenberg, Jan S.
2012-01-01
The present study explored the behavioral profile of individuals with fragile X syndrome during adolescence and adulthood. Individuals with both fragile X syndrome and autism (n = 30) were compared with (a) individuals diagnosed with fragile X syndrome (but not autism; n = 106) and (b) individuals diagnosed with autism (but not fragile X syndrome; n = 135) on measures of autism symptoms, adaptive functioning, behavior problems, and psychological symptoms. Results indicated that individuals dually diagnosed with fragile X syndrome and autism displayed greater communication and social reciprocity impairments than individuals with fragile X syndrome only. Individuals in the dually diagnosed group also exhibited higher levels of repetitive and challenging behaviors than either comparison group, suggesting a unique profile of vulnerability for those diagnosed with both fragile X syndrome and autism. PMID:22264109
Behavioral Phenotype of Fragile X Syndrome in Adolescence and Adulthood
ERIC Educational Resources Information Center
Smith, Leann E.; Barker, Erin T.; Seltzer, Marsha Mailick; Abbeduto, Leonard; Greenberg, Jan S.
2012-01-01
The present study explored the behavioral profile of individuals with fragile X syndrome during adolescence and adulthood. Individuals with both fragile X syndrome and autism (n = 30) were compared with (a) individuals diagnosed with fragile X syndrome (but not autism; n = 106) and (b) individuals diagnosed with autism (but not fragile X syndrome;…
Role of DNA secondary structures in fragile site breakage along human chromosome 10
Dillon, Laura W.; Pierce, Levi C. T.; Ng, Maggie C. Y.; Wang, Yuh-Hwa
2013-01-01
The formation of alternative DNA secondary structures can result in DNA breakage leading to cancer and other diseases. Chromosomal fragile sites, which are regions of the genome that exhibit chromosomal breakage under conditions of mild replication stress, are predicted to form stable DNA secondary structures. DNA breakage at fragile sites is associated with regions that are deleted, amplified or rearranged in cancer. Despite the correlation, unbiased examination of the ability to form secondary structures has not been evaluated in fragile sites. Here, using the Mfold program, we predict potential DNA secondary structure formation on the human chromosome 10 sequence, and utilize this analysis to compare fragile and non-fragile DNA. We found that aphidicolin (APH)-induced common fragile sites contain more sequence segments with potential high secondary structure-forming ability, and these segments clustered more densely than those in non-fragile DNA. Additionally, using a threshold of secondary structure-forming ability, we refined legitimate fragile sites within the cytogenetically defined boundaries, and identified potential fragile regions within non-fragile DNA. In vitro detection of alternative DNA structure formation and a DNA breakage cell assay were used to validate the computational predictions. Many of the regions identified by our analysis coincide with genes mutated in various diseases and regions of copy number alteration in cancer. This study supports the role of DNA secondary structures in common fragile site instability, provides a systematic method for their identification and suggests a mechanism by which DNA secondary structures can lead to human disease. PMID:23297364
Fragile X syndrome and fragile X-associated tremor ataxia syndrome.
Hall, Deborah A; Berry-Kravis, Elizabeth
2018-01-01
Fragile X-associated disorders encompass several conditions, which are caused by expansion mutations in the fragile X mental retardation 1 (FMR1) gene. Fragile X syndrome is the most common inherited etiology of intellectual disability and results from a full mutation or >200 CGG repeats in FMR1. It is associated with developmental delay, autism spectrum disorder, and seizures. Fragile X-associated tremor/ataxia syndrome is a progressive neurodegenerative disease that occurs in premutation carriers of 55-200 CGG repeats in FMR1 and is characterized by kinetic tremor, gait ataxia, parkinsonism, executive dysfunction, and neuropathy. Fragile X-associated primary ovarian insufficiency also occurs in premutation carrier women and manifests with infertility and early menopause. The diseases constituting fragile X-associated disorders differ mechanistically, due to the distinct molecular properties of premutation versus full mutations. Fragile X syndrome occurs when there is a lack of fragile X mental retardation protein (FMRP) due to FMR1 methylation and silencing. In fragile X-associated tremor ataxia syndrome, a toxic gain of function is postulated with the production of excess CGG repeat-containing FMR1 mRNA, abnormal translation of the repeat sequence leading to production of polyglycine, polyalanine, and other polypeptides and to outright deficits in translation leading to reduced FMRP at larger premutation sizes. The changes in underlying brain chemistry due to FMR1 mutations have led to therapeutic studies in these disorders, with some progress being made in fragile X syndrome. This paper also summarizes indications for testing, genetic counseling issues, and what the future holds for these disorders. Copyright © 2018 Elsevier B.V. All rights reserved.
Cholinergic Dysfunction in Fragile X Syndrome and Potential Intervention
Kesler, Shelli R; Lightbody, Amy A; Reiss, Allan L
2009-01-01
Males with fragile X syndrome are at risk for significant cognitive and behavioral deficits, particularly those involving executive prefrontal systems. Disruption of the cholinergic system secondary to fragile X mental retardation protein deficiency may contribute to the cognitive-behavioral impairments associated with fragile X. We measured choline in the dorsolateral prefrontal cortex of 9 males with fragile X syndrome and 9 age-matched typically developing controls using 1H magnetic resonance spectroscopy. Right choline/creatine was significantly reduced in the fragile X group compared to controls. In controls, both left and right choline was significantly positively correlated with intelligence and age was significantly negatively correlated with left choline. There were no correlations in the fragile X group. Subjects with fragile X syndrome participating in a pilot open-label trial of donepezil, an acetylcholinesterase inhibitor, demonstrated significantly improved cognitive-behavioral function. Studies utilizing biochemical neuroimaging techniques such as these have the potential to significantly impact the design of treatment strategies for fragile X syndrome and other genetic disorders by helping identify neurochemical targets for intervention as well as serving as metrics for treatment efficacy. PMID:19215057
ERIC Educational Resources Information Center
Ouyang, L.; Grosse, S.; Raspa, M.; Bailey, D.
2010-01-01
Background: The employment impact and financial burden experienced by families of children with fragile X syndrome (FXS) has not been quantified in the USA. Method: Using a national fragile X family survey, we analysed data on 1019 families with at least one child who had a full FXS mutation. Out-of-pocket expenditures related to fragile X were…
Heart Activity and Autistic Behavior in Infants and Toddlers with Fragile X Syndrome
Roberts, Jane E.; Tonnsen, Bridgette; Robinson, Ashley; Shinkareva, Svetlana V.
2014-01-01
The present study contrasted physiological arousal in infants and toddlers with fragile X syndrome to typically developing control participants and examined physiological predictors early in development to autism severity later in development in fragile X syndrome. Thirty-one males with fragile X syndrome (ages 8–40 months) and 25 age-matched control participants were included. The group with fragile X syndrome showed shorter interbeat intervals (IBIs), lower vagal tone (VT), and less modulation of IBI. Data suggested a nonlinear effect with IBI and autistic behavior; however, a linear effect with VT and autistic behavior emerged. These findings suggest that atypical physiological arousal emerges within the first year and predicts severity of autistic behavior in fragile X syndrome. These relationships are complex and dynamic, likely reflecting endogenous factors assumed to reflect atypical brain function secondary to reduced fragile X mental retardation protein. This research has important implications for the early identification and treatment of autistic behaviors in young children with fragile X syndrome. PMID:22515825
Fragile X-associated disorders: Don't miss them.
Birch, Rachael C; Cohen, Jonathan; Trollor, Julian N
2017-01-01
Fragile X-associated disorders are a family of inherited disorders caused by expansions in the Fragile X Mental Retardation 1 (FMR1) gene. Premutation expansions of the FMR1 gene confer risk for fragile X-associated primary ovarian insufficiency and fragile X-associated tremor ataxia syndrome, as well as other medical and psychiatric comorbidities. Premutation expansions of the FMR1 gene are common in the general population. However, fragile X-associated disorders are frequently under-recognised and often misdiagnosed. The aim of this article is to describe fragile X-associated disorders and identify specific considerations for general practitioners (GPs) during identification and management of these disorders. GPs have a critical role in the identification of fragile X-associated disorders, as well as coordination of complex care needs. Prompt recognition and appropriate management of these disorders and potential medical and psychiatric comorbidities will have important implications not only for the affected patient, but also other family members who may be at risk.
Kim, Jai-Hyun; Peacock, Matthew R.; George, Steven C.; Hughes, Christopher C.W.
2012-01-01
ALK1 (ACVRL1) is a member of the TGFβ receptor family and is expressed predominantly by arterial endothelial cells (EC). Mutations in ACVRL1 are responsible for Hereditary Hemorrhagic Telangiectasia Type 2 (HHT2), a disease manifesting as fragile vessels, capillary overgrowth, and numerous arterio-venous malformations (AVMs). Arterial EC also express EphrinB2, which has multiple roles in vascular development and angiogenesis and is known to be reduced in ACVRL1 knockout mice. Using an in vitro angiogenesis model we find that the Alk1 ligand BMP9 induces EphrinB2 in EC, and this is entirely dependent on expression of Alk1 and at least one of the co-receptors BMPRII or ActRII. BMP9 induces both ID1 and ID3, and both are necessary for full induction of EphrinB2. Loss of Alk1 or EphrinB2 results in increased arterial-venous anastomosis, while loss of Alk1 but not EphrinB2 results in increased VEGFR2 expression and enhanced capillary sprouting. Conversely, BMP9 blocks EC sprouting and this is dependent on Alk1, BMPRII/ActRII and ID1/ID3. Finally, notch signaling overcomes the loss of Alk1 – restoring EphrinB2 expression in EC, and curbing excess sprouting. Thus, in an in vitro model of HHT2, loss of Alk1 blocks BMP9 signaling, resulting in reduced EphrinB2 expression, enhanced VEGFR2 expression, and misregulated EC sprouting and anastomosis. PMID:22622516
Wang, Yao; Cui, Yazhou; Zhou, Xiaoyan; Han, Jinxiang
2015-01-01
Objective Osteogenesis imperfecta (OI) is a rare inherited skeletal disease, characterized by bone fragility and low bone density. The mutations in this disorder have been widely reported to be on various exonal hotspots of the candidate genes, including COL1A1, COL1A2, CRTAP, LEPRE1, and FKBP10, thus creating a great demand for precise genetic tests. However, large genome sizes make the process daunting and the analyses, inefficient and expensive. Therefore, we aimed at developing a fast, accurate, efficient, and cheaper sequencing platform for OI diagnosis; and to this end, use of an advanced array-based technique was proposed. Method A CustomSeq Affymetrix Resequencing Array was established for high-throughput sequencing of five genes simultaneously. Genomic DNA extraction from 13 OI patients and 85 normal controls and amplification using long-range PCR (LR-PCR) were followed by DNA fragmentation and chip hybridization, according to standard Affymetrix protocols. Hybridization signals were determined using GeneChip Sequence Analysis Software (GSEQ). To examine the feasibility, the outcome from new resequencing approach was validated by conventional capillary sequencing method. Result Overall call rates using resequencing array was 96–98% and the agreement between microarray and capillary sequencing was 99.99%. 11 out of 13 OI patients with pathogenic mutations were successfully detected by the chip analysis without adjustment, and one mutation could also be identified using manual visual inspection. Conclusion A high-throughput resequencing array was developed that detects the disease-associated mutations in OI, providing a potential tool to facilitate large-scale genetic screening for OI patients. Through this method, a novel mutation was also found. PMID:25742658
Study on the Progress of Ecological Fragility Assessment in China
NASA Astrophysics Data System (ADS)
Chen, Pei; Hou, Kang; Chang, Yue; Li, Xuxiang; Zhang, Yunwei
2018-02-01
The basic elements of human survival are based on the ecological environment. The development of social economic and the security of the ecological environment are closely linked and interact with each other. The fragility of the environment directly affects the stability of the regional ecosystem and the sustainable development of the ecological environment. As part of the division of the national ecological security, the assessment of ecological fragility has become a hot and difficult issue in environmental research, and researchers at home and abroad have systematically studied the causes and states of ecological fragility. The assessment of regional ecological fragility is a qualitative and quantitative analysis of the unbalanced distribution of ecological environment factors caused by human socio-economic activities or changes in ecosystems. At present, researches on ecological fragility has not formed a complete and unified index assessment system, and the unity of the assessment model has a direct impact on the accuracy of the index weights. Therefore, the discussion on selection of ecological fragility indexes and the improvement of ecological fragility assessment model is necessary, which is good for the improvement of ecological fragility assessment system in China.
The correlation between fragility, density, and atomic interaction in glass-forming liquids
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Lijin; Guan, Pengfei, E-mail: pguan@csrc.ac.cn; Wang, W. H.
2016-07-21
The fragility that controls the temperature-dependent viscous properties of liquids as the glass transition is approached, in various glass-forming liquids with different softness of the repulsive part of atomic interactions at different densities, is investigated by molecular dynamic simulations. We show that the landscape of fragility in purely repulsive systems can be separated into three regions denoted as R{sub I,} R{sub II}, and R{sub III}, respectively, with qualitatively disparate dynamic behaviors: R{sub I} which can be described by “softness makes strong glasses,” R{sub II} where fragility is independent of softness and can only be tuned by density, and R{sub III}more » with constant fragility, suggesting that density plays an unexpected role for understanding the repulsive softness dependence of fragility. What is more important is that we unify the long-standing inconsistence with respect to the repulsive softness dependence of fragility by observing that a glass former can be tuned more fragile if nonperturbative attraction is added into it. Moreover, we find that the vastly dissimilar influences of attractive interaction on fragility could be estimated from the structural properties of related zero-temperature glasses.« less
Schrell, Samantha K.; Boland, Kevin Sean; Cross, Justin Neil; ...
2017-01-18
In an attempt to further advance the understanding of plutonium coordination chemistry, we report a robust method for recycling and obtaining plutonium aqueous stock solutions that can be used as a convenient starting material in plutonium synthesis. This approach was used to prepare and characterize plutonium(IV) tetrachloride tris-diphenylsulfoxide, PuCl 4(OSPh 2) 3, by single crystal X-ray diffraction. The PuCl 4(OSPh 2) 3 compound represents a rare example of a 7-coordinate plutonium(IV) complex. Structural characterization of PuCl 4(OSPh 2) 3 by X-ray diffraction utilized a new containment method for radioactive crystals. The procedure makes use of epoxy, polyimide loops, and amore » polyester sheath to provide a robust method for safely containing and easily handling radioactive samples. Lastly, the described procedure is more user friendly than traditional containment methods that employ fragile quartz capillary tubes. Additionally, moving to polyester, instead of quartz, lowers the background scattering from the heavier silicon atoms.« less
Functional properties of honey, propolis, and royal jelly.
Viuda-Martos, M; Ruiz-Navajas, Y; Fernández-López, J; Pérez-Alvarez, J A
2008-11-01
Honey, propolis, and royal jelly, products originating in the beehive, are attractive ingredients for healthy foods. Honey has been used since ancient times as part of traditional medicine. Several aspects of this use indicate that it also has functions such as antibacterial, antioxidant, antitumor, anti-inflamatory, antibrowning, and antiviral. Propolis is a resinous substance produced by honeybees. This substance has been used in folk medicine since ancient times, due to its many biological properties to possess, such as antitumor, antioxidant, antimicrobial, anti-inflammatory, and immunomodulatory effects, among others. Royal jelly has been demonstrated to possess numerous functional properties such as antibacterial activity, anti-inflammatory activity, vasodilative and hypotensive activities, disinfectant action, antioxidant activity, antihypercholesterolemic activity, and antitumor activity. Biological activities of honey, propolis, and royal jelly are mainly attributed to the phenolic compounds such as flavonoids. Flavonoids have been reported to exhibit a wide range of biological activities, including antibacterial, antiviral, anti-inflammatory, antiallergic, and vasodilatory actions. In addition, flavonoids inhibit lipid peroxidation, platelet aggregation, capillary permeability and fragility, and the activity of enzyme systems including cyclo-oxygenase and lipoxygenase.
Systems fragility: The sociology of chaos.
Hodges, Lori R
2016-01-01
This article examines the concept of community fragility in emergency management from a systems perspective. Using literature that addresses fragility in four areas of complex systems, including ecosystems, social systems, sociotechnical systems, and complex adaptive systems, a theoretical framework focused on the emergency management field is created. These findings illustrate how community fragility factors can be used in the emergency management field to not only improve overall outcomes after disaster but also build less fragile systems and communities in preparation for future disasters.
Attendance at Fragile X Specialty Clinics: Facilitators and Barriers
ERIC Educational Resources Information Center
Kidd, Sharon A.; Raspa, Melissa; Clark, Renée; Usrey-Roos, Holly; Wheeler, Anne C.; Liu, Jessica A.; Wylie, Amanda; Sherman, Stephanie L.
2017-01-01
The objectives were to describe the demographic characteristics of children with Fragile X syndrome (FXS) and to determine predictors of attendance at Fragile X (FX) clinics. Findings from the Community Support Network (CSN) and Our Fragile X World (OFXW) samples showed that children who attended FX Clinics were mostly male, high-school aged or…
Medically Fragile Children: Report from State Committee on Medically Fragile Child Referent Group.
ERIC Educational Resources Information Center
Michigan State Dept. of Education, Lansing. Special Education Services.
This report is the product of a committee charged to define "medically fragile," explore the array of educational services available and/or needed for children in Michigan considered medically fragile, identify current information and gaps in the information, and identify areas of interagency collaboration. The report discusses critical…
Cognitive, Behavioral, and Adaptive Functioning in Fragile X and Non-Fragile X Retarded Men.
ERIC Educational Resources Information Center
Dykens, Elisabeth; And Others
1988-01-01
Evaluation of the cognitive, behavioral, and adaptive functioning of 12 retarded men with fragile X syndrome indicated that fragile X men were largely indistinguishable from comparison groups. They were, however, significantly more likely to have achieved levels of adaptive functioning commensurate with their intellectual abilities. (Author/DB)
Cell-type-specific replication initiation programs set fragility of the FRA3B fragile site.
Letessier, Anne; Millot, Gaël A; Koundrioukoff, Stéphane; Lachagès, Anne-Marie; Vogt, Nicolas; Hansen, R Scott; Malfoy, Bernard; Brison, Olivier; Debatisse, Michelle
2011-02-03
Common fragile sites have long been identified by cytogeneticists as chromosomal regions prone to breakage upon replication stress. They are increasingly recognized to be preferential targets for oncogene-induced DNA damage in pre-neoplastic lesions and hotspots for chromosomal rearrangements in various cancers. Common fragile site instability was attributed to the fact that they contain sequences prone to form secondary structures that may impair replication fork movement, possibly leading to fork collapse resulting in DNA breaks. Here we show, in contrast to this view, that the fragility of FRA3B--the most active common fragile site in human lymphocytes--does not rely on fork slowing or stalling but on a paucity of initiation events. Indeed, in lymphoblastoid cells, but not in fibroblasts, initiation events are excluded from a FRA3B core extending approximately 700 kilobases, which forces forks coming from flanking regions to cover long distances in order to complete replication. We also show that origins of the flanking regions fire in mid-S phase, leaving the site incompletely replicated upon fork slowing. Notably, FRA3B instability is specific to cells showing this particular initiation pattern. The fact that both origin setting and replication timing are highly plastic in mammalian cells explains the tissue specificity of common fragile site instability we observed. Thus, we propose that common fragile sites correspond to the latest initiation-poor regions to complete replication in a given cell type. For historical reasons, common fragile sites have been essentially mapped in lymphocytes. Therefore, common fragile site contribution to chromosomal rearrangements in tumours should be reassessed after mapping fragile sites in the cell type from which each tumour originates.
Tracking development assistance for health to fragile states: 2005-2011.
Graves, Casey M; Haakenstad, Annie; Dieleman, Joseph L
2015-03-19
Development assistance for health (DAH) has grown substantially, totaling more than $31.3 billion in 2013. However, the degree that countries with high concentrations of armed conflict, ethnic violence, inequality, debt, and corruption have received this health aid and how that assistance might be different from the funding provided to other countries has not been assessed. We combine DAH estimates and a multidimensional fragile states index for 2005 through 2011. We disaggregate and compare total DAH disbursed for fragile states versus stable states. Between 2005 and 2011, DAH per person in fragile countries increased at an annualized rate of 5.4%. In 2011 DAH to fragile countries totaled $6.2 billion, which is $5.05 per person. This is 43% of total DAH that is traced to a country. Comparing low-income countries, funding channeled to fragile countries was $7.22 per person while stable countries received $11.15 per person. Relative to stable countries, donors preferred to provide more funding to low-income fragile countries that have refugees or ongoing external intervention but tended to avoid providing funding to countries with political gridlock, flawed elections, or economic decline. In 2011, Ethiopia received the most health aid of all fragile countries, while the United States provided the most funds to fragile countries. In 2011, 1.2 billion people lived in fragile countries. DAH can bolster health systems and might be especially valuable in providing long-term stability in fragile environments. While external health funding to these countries has increased since 2005, it is, in per person terms, almost half as much as the DAH provided to stable countries of comparable income levels.
Heart Activity and Autistic Behavior in Infants and Toddlers with Fragile X Syndrome
ERIC Educational Resources Information Center
Roberts, Jane E.; Tonnsen, Bridgette; Robinson, Ashley; Shinkareva, Svetlana V.
2012-01-01
The present study contrasted physiological arousal in infants and toddlers with fragile X syndrome to typically developing control participants and examined physiological predictors early in development to autism severity later in development in fragile X syndrome. Thirty-one males with fragile X syndrome (ages 8-40 months) and 25 age-matched…
Selective Spatial Processing Deficits in an At-Risk Subgroup of the Fragile X Premutation
ERIC Educational Resources Information Center
Hocking, Darren R.; Kogan, Cary S.; Cornish, Kim M.
2012-01-01
Until a decade ago, it was assumed that males with the fragile X premutation were unaffected by any cognitive phenotype. Here we examined the extent to which CGG repeat toxicity extends to visuospatial functioning in male fragile X premutation carriers who are asymptomatic for a late-onset neurodegenerative disorder, fragile X-associated…
Sasakawa, S; Tokunaga, E; Hasegawa, G; Nakagawa, S
1977-09-01
The coil planet centrifuge (CPC) can be used to measure the osmotic fragility of erythrocytes. Fragility measured by this method alters when different salts are used. The CPC and Parpart methods were used to measure the changes during storage in red cell osmotic fragility in ACD or CPD blood with or without adenine. More marked changes were detected by the CPC method, especially in old cells. The changes of fragility of erythrocytes during storage seem to occur mainly in old cells. Adenine is effective in preventing such changes.
Obesity, Food Selectivity, and Physical Activity in Individuals with Fragile X Syndrome
ERIC Educational Resources Information Center
Raspa, Melissa; Bailey, Donald B., Jr.; Bishop, Ellen; Holiday, David; Olmsted, Murrey
2010-01-01
National survey data from 884 families were used to examine the overall health of children and adults with fragile X syndrome. Results indicate the rate of obesity in adults with fragile X syndrome is similar to the general population (30%). Male children with fragile X syndrome, however, had higher rates of obesity (31%) when compared with…
Differential Impact of the "FMR1" Gene on Visual Processing in Fragile X Syndrome
ERIC Educational Resources Information Center
Kogan, Cary S.; Boutet, Isabelle; Cornish, Kim; Zangenehpour, Shahin; Mullen, Kathy T.; Holden, Jeanette J. A.; Kaloustian, Vazken M. Der; Andermann, Eva; Chaudhuri, Avi
2004-01-01
Fragile X syndrome (FXS) is the most common form of heritable mental retardation, affecting (~ around) 1 in 4000 males. The syndrome arises from expansion of a trinucleotide repeat in the 5'-untranslated region of the fragile X mental retardation 1 ("FMR1") gene, leading to methylation of the promoter sequence and lack of the fragile X mental…
ERIC Educational Resources Information Center
Utari, Agustini; Chonchaiya, Weerasak; Rivera, Susan M.; Schneider, Andrea; Hagerman, Randi J.; Faradz, Sultana M. H.; Ethell, Iryna M.; Nguyen, Danh V.
2010-01-01
Minocycline can rescue the dendritic spine and synaptic structural abnormalities in the fragile X knock-out mouse. This is a review and preliminary survey to document side effects and potential outcome measures for minocycline use in the treatment of individuals with fragile X syndrome. We surveyed 50 patients with fragile X syndrome who received…
ERIC Educational Resources Information Center
Greenberg, Jan S.; Seltzer, Marsha Mailick; Baker, Jason K.; Smith, Leann E.; Warren, Steven F.; Brady, Nancy; Hong, Jinkuk
2012-01-01
We examine how the family environment is associated with aspects of the Fragile X syndrome phenotype during childhood, adolescence, and adulthood. Mothers of children (n = 48), adolescents (n = 85), and adults (n = 34) with Fragile X syndrome participated in a multisite study. For children and adults with Fragile X syndrome, the presence of warmth…
Remote sensing research on fragile ecological environment in continental river basin
NASA Astrophysics Data System (ADS)
Wang, Ranghui; Peng, Ruyan; Zhang, Huizhi
2003-07-01
Based on some remote sensing data and software platform of image processing and analysis, the standard image for ecological thematic mapping is decided. Moreover, the vegetation type maps and land sandy desertification type maps are made. Relaying on differences of natural resources and ecological environment in Tarim River Basin, the assessment indicator system and ecological fragility index (EFI) of ecological environment are built up. The assessment results are very severely. That is, EFI is only 0.08 in Akesu River Basin, it belongs to slight fragility area. EFI of Yarkant River Basin and upper reaches of Tarim River Basin are 0.23 and 0.25 respectively, both of them belong to general fragility areas. Meanwhile, EFI of Hotan River Basin and middle reaches of Tarim River Basin are 0.32 and 0.49 respectively; they all belong to middle fragility areas. However, the fragility of the lower reaches of Tarim River Basin belongs to severe fragility area that the EFI is 0.87.The maladjustment among water with hot and land as well as salt are hindrance of energy transfer and material circulation and information transmission. It is also the main reason that caused ecological environment fragility.
Longitudinal Profiles of Adaptive Behavior in Fragile X Syndrome
Quintin, Eve-Marie; Jo, Booil; Lightbody, Amy A.; Hazlett, Heather Cody; Piven, Joseph; Hall, Scott S.; Reiss, Allan L.
2014-01-01
OBJECTIVE: To examine longitudinally the adaptive behavior patterns in fragile X syndrome. METHOD: Caregivers of 275 children and adolescents with fragile X syndrome and 225 typically developing children and adolescents (2–18 years) were interviewed with the Vineland Adaptive Behavior Scales every 2 to 4 years as part of a prospective longitudinal study. RESULTS: Standard scores of adaptive behavior in people with fragile X syndrome are marked by a significant decline over time in all domains for males and in communication for females. Socialization skills are a relative strength as compared with the other domains for males with fragile X syndrome. Females with fragile X syndrome did not show a discernible pattern of developmental strengths and weaknesses. CONCLUSIONS: This is the first large-scale longitudinal study to show that the acquisition of adaptive behavior slows as individuals with fragile X syndrome age. It is imperative to ensure that assessments of adaptive behavior skills are part of intervention programs focusing on childhood and adolescence in this condition. PMID:25070318
Human Lymphoid Translocation Fragile Zones Are Hypomethylated and Have Accessible Chromatin
Lu, Zhengfei; Tsai, Albert G.; Pardo, Carolina E.; Müschen, Markus; Kladde, Michael P.
2015-01-01
Chromosomal translocations are a hallmark of hematopoietic malignancies. CG motifs within translocation fragile zones (typically 20 to 600 bp in size) are prone to chromosomal translocation in lymphomas. Here we demonstrate that the CG motifs in human translocation fragile zones are hypomethylated relative to the adjacent DNA. Using a methyltransferase footprinting assay on isolated nuclei (in vitro), we find that the chromatin at these fragile zones is accessible. We also examined in vivo accessibility using cellular expression of a prokaryotic methylase. Based on this assay, which measures accessibility over a much longer time interval than is possible with in vitro methods, these fragile zones were found to be more accessible than the adjacent DNA. Because DNA within the fragile zones can be methylated by both cellular and exogenous methyltransferases, the fragile zones are predominantly in a duplex DNA conformation. These observations permit more-refined models for why these zones are 100- to 1,000-fold more prone to undergo chromosomal translocation than the adjacent regions. PMID:25624348
Boland, Michael J; Nazor, Kristopher L; Tran, Ha T; Szücs, Attila; Lynch, Candace L; Paredes, Ryder; Tassone, Flora; Sanna, Pietro Paolo; Hagerman, Randi J; Loring, Jeanne F
2017-03-01
New research suggests that common pathways are altered in many neurodevelopmental disorders including autism spectrum disorder; however, little is known about early molecular events that contribute to the pathology of these diseases. The study of monogenic, neurodevelopmental disorders with a high incidence of autistic behaviours, such as fragile X syndrome, has the potential to identify genes and pathways that are dysregulated in autism spectrum disorder as well as fragile X syndrome. In vitro generation of human disease-relevant cell types provides the ability to investigate aspects of disease that are impossible to study in patients or animal models. Differentiation of human pluripotent stem cells recapitulates development of the neocortex, an area affected in both fragile X syndrome and autism spectrum disorder. We have generated induced human pluripotent stem cells from several individuals clinically diagnosed with fragile X syndrome and autism spectrum disorder. When differentiated to dorsal forebrain cell fates, our fragile X syndrome human pluripotent stem cell lines exhibited reproducible aberrant neurogenic phenotypes. Using global gene expression and DNA methylation profiling, we have analysed the early stages of neurogenesis in fragile X syndrome human pluripotent stem cells. We discovered aberrant DNA methylation patterns at specific genomic regions in fragile X syndrome cells, and identified dysregulated gene- and network-level correlates of fragile X syndrome that are associated with developmental signalling, cell migration, and neuronal maturation. Integration of our gene expression and epigenetic analysis identified altered epigenetic-mediated transcriptional regulation of a distinct set of genes in fragile X syndrome. These fragile X syndrome-aberrant networks are significantly enriched for genes associated with autism spectrum disorder, giving support to the idea that underlying similarities exist among these neurodevelopmental diseases. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Risk of fragility fracture among patients with sarcoidosis: a population-based study 1976-2013.
Ungprasert, P; Crowson, C S; Matteson, E L
2017-06-01
Incidence of fragility fracture of a population-based cohort of 345 patients with sarcoidosis was compared with age and sex-matched comparators. The incidence of fragility fracture was higher among patients with sarcoidosis with hazard ratio (HR) of 2.18. Several chronic inflammatory disorders increase the risk of fragility fracture. However, little is known about the risk of fragility fracture in patients with sarcoidosis. This study was conducted using a previously identified population-based cohort of 345 patients with incident sarcoidosis from Olmsted County, Minnesota. Diagnosis of sarcoidosis required physician diagnosis supported by biopsy showing non-caseating granuloma, radiographic evidence of intrathoracic sarcoidosis, and compatible clinical presentations without evidence of other granulomatous diseases. Sex and age-matched subjects randomly selected from the same underlying population were used as comparators. Medical records of cases and comparators were reviewed for baseline characteristics and incident fragility fracture. Fragility fractures were observed in 34 patients with sarcoidosis, corresponding to a cumulative incidence of 5.6% at 10 years, while 18 fragility fractures were observed among comparators for a cumulative incidence of 2.4% at 10 years. The HR of fragility fractures among cases compared with comparators was 2.18 (95% confidence interval [CI], 1.23-3.88). The risk of fragility fracture by site was significantly higher among patients with sarcoidosis, and was due to a higher rate of distal forearm fracture (HR 3.58; 95% CI 1.53-8.40). Statistically non-significant increased risk was also observed in proximal femur (HR 1.66; 95% CI 0.45-6.06) and proximal humerus (HR 3.27; 95% CI 0.66-16.21). Risk of vertebral fracture was not increased (HR 1.00; 95% CI 0.32-3.11). Patients with sarcoidosis have an increased risk of fragility fracture which is primarily driven by the higher incidence of distal forearm fracture.
Fragile X syndrome is the most common form of inherited developmental disability. A problem with a specific gene causes ... the protein. This causes the symptoms of Fragile X. People with only a small change in the ...
Fragility correlates thermodynamic and kinetic properties of glass forming liquids
DOE Office of Scientific and Technical Information (OSTI.GOV)
Reddy, C.Narayana; Viswanatha, R.; Chethana, B.K.
2015-03-15
Graphical abstract: The suggested new fragility parameter correlates viscosity and configurational entropy. - Highlights: • A new fragility function, F=ΔT/ΔC{sub p}×C{sub p}{sup l}/T{sub g} has been proposed. • A three parameter viscosity function using the new F reproduces Angell fragility plot. • A new ΔC{sub p} function is derived which directly relates Adam–Gibbs function with the fragility based viscosity function. - Abstract: In our earlier communication we proposed a simple fragility determining function, ([NBO]/V{sub m}{sup 3}T{sub g}), which we have now used to analyze several glass systems using available thermal data. A comparison with similar fragility determining function, ΔC{sub p}/C{submore » p}{sup l}, introduced by Chryssikos et al. in their investigation of lithium borate glasses has also been performed and found to be more convenient quantity for discussing fragilities. We now propose a new function which uses both ΔC{sub p} and ΔT and which gives a numerical fragility parameter, F whose value lies between 0 and 1 for glass forming liquids. F can be calculated through the use of measured thermal parameters ΔC{sub p}, C{sub p}{sup l}, T{sub g} and T{sub m}. Use of the new fragility values in reduced viscosity equation reproduces the whole range of viscosity curves of the Angell plot. The reduced viscosity equation can be directly compared with the Adam–Gibbs viscosity equation and a heat capacity function can be formulated which reproduces satisfactorily the ΔC{sub p} versus ln(T{sub r}) curves and hence the configurational entropy.« less
A Trial of Metformin in Individuals With Fragile X Syndrome
2018-06-05
Fragile X Syndrome; Fragile X Mental Retardation Syndrome; Mental Retardation, X Linked; Genetic Diseases, X-Linked; Trinucleotide Repeat Expansion; Fra(X) Syndrome; Intellectual Disability; FXS; Neurobehavioral Manifestations; Sex Chromosome Disorders
DOE Office of Scientific and Technical Information (OSTI.GOV)
Valverde,R.; Poznyakova, I.; Kajander, T.
Fragile X syndrome is the most common form of inherited mental retardation in humans, with an estimated prevalence of about 1 in 4000 males. Although several observations indicate that the absence of functional Fragile X Mental Retardation Protein (FMRP) is the underlying basis of Fragile X syndrome, the structure and function of FMRP are currently unknown. Here, we present an X-ray crystal structure of the tandem KH domains of human FMRP, which reveals the relative orientation of the KH1 and KH2 domains and the location of residue Ile304, whose mutation to Asn is associated with a particularly severe incidence ofmore » Fragile X syndrome. We show that the Ile304Asn mutation both perturbs the structure and destabilizes the protein.« less
Martin, Gary E.; Roberts, Joanne E.; Helm-Estabrooks, Nancy; Sideris, John; Vanderbilt, Jacqueline; Moskowitz, Lauren
2012-01-01
Verbal perseveration is a frequently reported language characteristic of males with Fragile X syndrome and may be a defining feature or hallmark of the syndrome. We compared the verbal perseveration of boys with Fragile X syndrome with (n = 29) and without (n = 30) autism spectrum disorder, boys with Down syndrome (n = 27), and typically developing boys (n = 25) at similar nonverbal mental ages. During a social interaction, boys with both Fragile X syndrome and autism spectrum disorder produced significantly more topic perseveration than all other groups. In social interaction as compared to narration, boys with Fragile X syndrome (regardless of autism status) produced significantly more topic perseveration. These findings suggest that autism status, as well as language sampling context, affect perseveration in boys with Fragile X syndrome. PMID:22998486
Choi, Catherine H; Schoenfeld, Brian P; Bell, Aaron J; Hinchey, Paul; Kollaros, Maria; Gertner, Michael J; Woo, Newton H; Tranfaglia, Michael R; Bear, Mark F; Zukin, R Suzanne; McDonald, Thomas V; Jongens, Thomas A; McBride, Sean M J
2011-03-22
Fragile X syndrome is the leading single gene cause of intellectual disabilities. Treatment of a Drosophila model of Fragile X syndrome with metabotropic glutamate receptor (mGluR) antagonists or lithium rescues social and cognitive impairments. A hallmark feature of the Fragile X mouse model is enhanced mGluR-dependent long-term depression (LTD) at Schaffer collateral to CA1 pyramidal synapses of the hippocampus. Here we examine the effects of chronic treatment of Fragile X mice in vivo with lithium or a group II mGluR antagonist on mGluR-LTD at CA1 synapses. We find that long-term lithium treatment initiated during development (5-6 weeks of age) and continued throughout the lifetime of the Fragile X mice until 9-11 months of age restores normal mGluR-LTD. Additionally, chronic short-term treatment beginning in adult Fragile X mice (8 weeks of age) with either lithium or an mGluR antagonist is also able to restore normal mGluR-LTD. Translating the findings of successful pharmacologic intervention from the Drosophila model into the mouse model of Fragile X syndrome is an important advance, in that this identifies and validates these targets as potential therapeutic interventions for the treatment of individuals afflicted with Fragile X syndrome. Copyright © 2010 Elsevier B.V. All rights reserved.
Beyond the Factor of Safety: Developing Fragility Curves to Characterize System Reliability
2010-07-01
increasingly common compo- nents of flood risk assessments. This report introduces the concept of the fragility curve and shows how fragility curves are...curves are identified in the literature on structures and risk assessment to identify what methods have been used to develop fragility curves in...and disadvantages of the various approaches are considered. DISCLAIMER: The contents of this report are not to be used for advertising
Mauch, Verena; Weil, Diana; Munim, Aayid; Boillot, Francois; Coninx, Rudi; Huseynova, Sevil; Powell, Clydette; Seita, Akihiro; Wembanyama, Henriette; van den Hof, Susan
2010-07-01
Health care delivery is particularly problematic in fragile states often connected with increased incidence of communicable diseases, among them tuberculosis. This article draws upon experiences in tuberculosis control in four fragile states from which four lessons learned were derived. A structured inventory to extract common themes specific for TB control in fragile states was conducted among twelve providers of technical assistance who have worked in fragile states. The themes were applied to the TB control programs of Afghanistan, DR Congo, Haiti and Somalia during the years 2000-2006. Case notifications and treatment outcomes have increased in all four countries since 2003 (treatment success rates 81-90%). Access to care and case detection however have remained insufficient (case detection rates 39-62%); There are four lessons learned: 1. TB control programs can function in fragile states. 2. National program leadership and stewardship are essential for quality and sustained TB control. 3. Partnerships with non-governmental providers are vital for continuous service delivery; 4. TB control programs in fragile states require consistent donor support. Despite challenges in management, coordination, security, logistics and funding, TB control programs can function in fragile states, but face considerable problems in access to diagnosis and treatment and therefore case detection. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.
Genetics Home Reference: fragile X syndrome
... Citation on PubMed Koukoui SD, Chaudhuri A. Neuroanatomical, molecular genetic, and behavioral correlates of fragile X syndrome. Brain ... GJ, Dictenberg J. The fragile X syndrome: from molecular genetics to neurobiology. Ment Retard Dev Disabil Res Rev. ...
Growth in stature in fragile X families: A mixed longitudinal study
DOE Office of Scientific and Technical Information (OSTI.GOV)
Loesch, D.Z.; Huggins, R.M.; Hoang, N.H.
1995-09-11
The effect of fragile X on growth in stature was estimated in individuals aged 5-20 years from 50 fragile X families. The multivariate normal model for pedigree analysis was applied to the mixed longitudinal data, which varied with regard to intervals between the measurements and their number in individual subjects, totalling 349 measurement data points from fragile X families, and 292 data points from unrelated normal subjects. The results of genetic and regression analysis showed that, in fragile X boys and girls, total pubertal height gain is impaired, whereas the rate of growth during the preadolescent period is increased, comparedmore » with the growth rate of nonfragile X subjects. Moreover, the growth parameters in fragile X males were found to be correlated with the size of CGG trinucleotide expansion. The hypothesis of premature activation of the hypothalamo-pituitary gonadal axis is postulated as the cause of growth impairment in fragile X boys and girls, which should be verified by data on the timing of pubertal stages, hormone levels, and bone maturation. 33 refs., 2 figs., 3 tabs.« less
Fragile X Syndrome: Keys to the Molecular Genetics of Synaptic Plasticity
ERIC Educational Resources Information Center
Lombroso, Paul J.; Ogren, Marilee P.
2008-01-01
Fragile X syndrome, the most common form of inherited mental retardation is discussed. The relationship between specific impairments in synaptic plasticity and Fragile X syndrome is investigated as it strengthens synaptic contacts between neurons.
Nuclear Power Plant Mechanical Component Flooding Fragility Experiments Status
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pope, C. L.; Savage, B.; Johnson, B.
This report describes progress on Nuclear Power Plant mechanical component flooding fragility experiments and supporting research. The progress includes execution of full scale fragility experiments using hollow-core doors, design of improvements to the Portal Evaluation Tank, equipment procurement and initial installation of PET improvements, designation of experiments exploiting the improved PET capabilities, fragility mathematical model development, Smoothed Particle Hydrodynamic simulations, wave impact simulation device research, and pipe rupture mechanics research.
ERIC Educational Resources Information Center
Howell, Peter
2008-01-01
Van Borsel, Dor, and Rondal (2007) examined the speech of seven boys and two young male adults with fragile X syndrome and considered whether their speech was comparable to that reported in the developmental stuttering literature. They listed five criteria which led them to conclude that the speech patterns of speakers with fragile X syndrome…
Strength of the repulsive part of the interatomic potential determines fragility in metallic liquids
NASA Astrophysics Data System (ADS)
Pueblo, Christopher E.; Sun, Minhua; Kelton, K. F.
2017-08-01
The dynamical behaviour of liquids is frequently characterized by the fragility, which can be defined from the temperature dependence of the shear viscosity, η (ref. ). For a strong liquid, the activation energy for η changes little with cooling towards the glass transition temperature, Tg. The change is much greater in fragile liquids, with the activation energy becoming very large near Tg. While fragility is widely recognized as an important concept--believed, for example, to play an important role in glass formation--the microscopic origin of fragility is poorly understood. Here, we present new experimental evidence showing that fragility reflects the strength of the repulsive part of the interatomic potential, which can be determined from the steepness of the pair distribution function near the hard-sphere cutoff. On the basis of an analysis of scattering data from ten different metallic alloy liquids, we show that stronger liquids have steeper repulsive potentials.
Keall, Michael; Frith, William
2004-12-01
It is well established that older drivers' fragility is an important factor associated with higher levels of fatal crash involvement for older drivers. There has been less research on age-related fragility with respect to the sort of minor injuries that are more common in injury crashes. This study estimates a quantity that is related to injury fragility: the probability that a driver or a passenger of that driver will be injured in crashes involving two cars. The effects of other factors apart from drivers' fragility are included in this measure, including the fragility of the passengers, the crashworthiness of cars driven, seatbelt use by the occupants, and characteristics of crashes (including configuration and impact speed). The car occupant injury liability estimates appropriately includes these factors to adjust risk curves by age, gender, and speed limit accounting for overrepresentation in crashes associated with fragility and these other factors.
Keng Yin Loh; King Hock Shong; Soo Nie Lan; Lo, Wan-Yi; Shu Yuen Woon
2008-01-01
Osteoporosis is a silent disease and becomes clinically significant in the presence of fragility fracture. Identifying risk factors that are associated with osteoporosis in the community is important in reducing the incidence of fragility fracture. The aim of this study is to identify risk factors associated with fragility fracture in the Seremban District of Malaysia. This is a population comparison study between orthopedic ward patients and outpatients attending a community health clinic for 6 months. Epidemiological data and the possible risk factors for osteoporosis were collected by direct interview. This study demonstrates that advancing age, low body weight, smoking, lack of regular exercise, low consumption of calcium containing foods, and using bone depleting drugs (steroids, thyroid hormone, and frusemides) are major risk factors for fragility fracture. Most of these risk factors are modifiable through effective lifestyle intervention.
The quest for fragile X biomarkers.
Westmark, Cara J
2014-12-01
Fragile X is the most common form of inherited intellectual disability and the leading known genetic cause of autism. There is currently no cure or approved medication for fragile X although various drugs target specific disease symptoms and a large number of therapeutics are in various stages of clinical development. Multiple recent clinical trials have failed on their primary endpoints indicating that there is a compelling need for validated biomarkers and outcome measures in fragile X. There are currently no validated blood-based biomarkers to assess disease severity or to monitor drug efficacy in fragile X syndrome. Herein, we review candidate blood protein biomarkers including extracellular-regulated kinase, phosphoinositide 3-kinase, matrix metalloproteinase 9, amyloid-beta and amyloid-beta protein precursor. Bench-to-bedside plans for fragile X syndrome are severely limited by the lack of validated outcome measures. The reviewed candidate biomarkers are at early stages of validation and deserve further investigation.
The mGluR theory of fragile X mental retardation.
Bear, Mark F; Huber, Kimberly M; Warren, Stephen T
2004-07-01
Many of the diverse functional consequences of activating group 1 metabotropic glutamate receptors require translation of pre-existing mRNA near synapses. One of these consequences is long-term depression (LTD) of transmission at hippocampal synapses. Loss of fragile X mental retardation protein (FMRP), the defect responsible for fragile X syndrome in humans, increases LTD in mouse hippocampus. This finding is consistent with the growing evidence that FMRP normally functions as a repressor of translation of specific mRNAs. Here we present a theory that can account for diverse neurological and psychiatric aspects of fragile X syndrome, based on the assumption that many of the protein-synthesis-dependent functions of metabotropic receptors are exaggerated in fragile X syndrome. The theory suggests new directions for basic research as well as novel therapeutic approaches for the treatment of humans with fragile X, the most frequent inherited cause of mental retardation and an identified cause of autism.
The Role of Fragile Sites in Sporadic Papillary Thyroid Carcinoma
Dillon, Laura W.; Lehman, Christine E.; Wang, Yuh-Hwa
2012-01-01
The incidence of thyroid cancer is increasing, especially papillary thyroid carcinoma (PTC), making it currently the fastest-growing cancer among women. Reasons for this increase remain unclear, but several risk factors including radiation exposure and improved detection techniques have been suggested. Recently, the induction of chromosomal fragile site breakage was found to result in the formation of RET/PTC1 rearrangements, a common cause of PTC. Chromosomal fragile sites are regions of the genome with a high susceptibility to forming DNA breaks and are often associated with cancer. Exposure to a variety of external agents can induce fragile site breakage, which may account for some of the observed increase in PTC. This paper discusses the role of fragile site breakage in PTC development, external fragile site-inducing agents that may be potential risk factors for PTC, and how these factors are especially targeting women. PMID:22762011
Fragile X-associated tremor/ataxia syndrome: another phenotype of the fragile X gene.
Hessl, David; Grigsby, Jim
2016-08-01
Neuropsychologists have an important role in evaluating patients with fragile X-associated disorders, but most practitioners are unaware of the recently identified neurodegenerative movement disorder known as fragile X-associated tremor ataxia syndrome (FXTAS). The objective of this editorial is to orient the reader to FXTAS and highlight the importance of clinical neuropsychology in describing the fragile X premutation phenotype and the role practitioners may have in assessing and monitoring patients with or at risk for neurodegeneration. We issued a call for papers for the special issue, highlighting the primary objective of familiarizing clinical neuropsychologists with FXTAS, and with the neuropsychological phenotype of both male and female asymptomatic carriers. Eight papers are included, including an overview of the fragile X-associated disorders (Grigsby), a review of the neuroradiological and neurological aspects of FXTAS and how the disorder compares to other movement disorders (O'Keefe et al.), a perspective on the prominence of white matter disease and dementia in FXTAS (Filley), and a review of mouse models of FXTAS (Foote). There are four research papers, including one on self-reported memory problems in FXTAS (Birch et al.), and three papers focused on the neuropsychiatric aspects of the fragile X premutation, a review (Bourgeois), an examination of autism-related traits (Schneider), and a research paper on executive functioning and psychopathology (Grigsby). The issue highlights the importance of awareness of fragile X-associated disorders for neuropsychologists, an awareness that must reach beyond neurodevelopmental aspects related to fragile X syndrome into the realm of neurodegenerative disease and aging.
Hunsaker, Michael R.
2013-01-01
It has become increasingly important that the field of behavioral genetics identifies not only the gross behavioral phenotypes associated with a given mutation, but also the behavioral endophenotypes that scale with the dosage of the particular mutation being studied. Over the past few years, studies evaluating the effects of the polymorphic CGG trinucleotide repeat on the FMR1 gene underlying Fragile X-Associated Disorders have reported preliminary evidence for a behavioral endophenotype in human Fragile X Premutation carrier populations as well as the CGG knock-in (KI) mouse model. More recently, the behavioral experiments used to test the CGG KI mouse model have been extended to the Fmr1 knock-out (KO) mouse model. When combined, these data provide compelling evidence for a clear neurocognitive endophenotype in the mouse models of Fragile X-Associated Disorders such that behavioral deficits scale predictably with genetic dosage. Similarly, it appears that the CGG KI mouse effectively models the histopathology in Fragile X-Associated Disorders across CGG repeats well into the full mutation range, resulting in a reliable histopathological endophenotype. These endophenotypes may influence future research directions into treatment strategies for not only Fragile X Syndrome, but also the Fragile X Premutation and Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS). PMID:24627796
Fragile X-Associated Primary Ovarian Insufficiency (FXPOI): Condition Information
... Research Information Find a Study Resources and Publications Turner Syndrome Condition Information NICHD Research Information Find a Study ... fragilex.org/fragile-x-associated-disorders/fragile-x-syndrome/ ... W., York Moore. D., & Turner, G. M. (1996). Confirmation of early menopause in ...
Scaling up nutrition in fragile and conflict-affected states: the pivotal role of governance.
Taylor, Sebastian A J; Perez-Ferrer, Carolina; Griffiths, Andrew; Brunner, Eric
2015-02-01
Acute and chronic undernutrition undermine conditions for health, stability and socioeconomic development across the developing world. Although fragile and conflict-affected states have some of the highest rates of undernutrition globally, their response to the multilateral 'Scaling Up Nutrition' (SUN) initiative in its first two-year period was ambivalent. The purpose of this research was to investigate factors affecting fragile and conflict-affected states' engagement with SUN, and to examine what differentiated those fragile states that joined SUN in its first phase from those that did not. Drawing on global databases (Unicef, World Bank, UNDP), and qualitative country case studies (Afghanistan, the Democratic Republic of Congo, Sierra Leone, Pakistan and Yemen) we used bivariate logistic regressions and principal component analysis to assess social, economic and political factors across 41 fragile states looking for systematic differences between those that had signed up to SUN before March 2013 (n = 16), and those that had not (n = 25). While prevalence of malnutrition, health system functioning and level of citizen empowerment had little or no impact on a fragile state's likelihood of joining SUN, the quality of governance (QOG) strongly predicted accession. SUN-signatory fragile states scored systematically better on the World Bank's Country Policy and Institutional Assessment (CPIA) and the Worldwide Governance Indicators 'effectiveness of government' indices. We conclude that strengthening governance in fragile states may enhance their engagement with initiatives such as SUN, but also (recognising the potential for endogeneity), that the way aid is structured and delivered in fragile states may be an underlying determinant of whether and how governance in such contexts improves. The research demonstrates that more nuanced analysis of conditions within and among countries classed as 'fragile and conflict-affected' is both possible and necessary if aid policies are to be shaped in ways that support rather than undermine growth in governance capacity. Copyright © 2014 Elsevier Ltd. All rights reserved.
Dzhokhadze, T A; Ganozishvili, M N; Lezhava, T A
2008-09-01
Expression rates of chromosome fragile sites in peripheral blood lymphocytes have been studied in clinically healthy individuals of different age groups (20-38 yrs and 75-86 yrs) and breast cancer patients (8 cases). In individuals with a normal check-up of different age groups the heavy metal (nickel, zinc and cobalt) ions were also examined on their influence on the expression of the fragile sites and the peptide bioregulators (Livagen and Epithalon) were tested on their ability to correct the pattern of expression. Short-term lymphocyte cultures were used as tested material. The analysis showed that the chromosomes of people from young and old age groups differ from each other by the expression pattern of fragile sites - the chromosomes of young individuals were found to be more active by spontaneous formation of fragile sites. They were also sensitive to their induction by heavy metals. Both tested bioregulators lessen heavy metals effect that was statistically reliable only for the young people group. As for the patients with breast cancer general elevated fragility of chromosomes and specific distribution of the fragile sites along the chromosomes were revealed.
NASA Astrophysics Data System (ADS)
Sujadi, H.; Bastian, A.; Tira
2018-05-01
In the city, many trees are found uprooted and cause accidents and many losses. No exception in the area of Majalengka Regency of West Java Province which can also anytime an accident or disaster caused by fallen trees, where in Majalengka district is logging trees on the street and public places are not done regularly. Based on the above problems, the need for tools that can detect a porous tree, to assist in the sorting of trees which should be felled and not felled by the party who has the authority of the general management of BMCK. Previously created tools to detect porous trees imported from Hungary and Germany, namely Arbosonic3D and Sonic Tomography. This design uses piezoelectric sensors to detect how much pressure is received by fragile and fragile trees, of course the fragile and fragile strength of trees will be different when exposed to the same pressure given the fragile density of fragile and fragile trees, then the data sent to Arduino Uno R3 to be processed into an information. This research produces a means of detecting the loss of a tree for early detection and no falling trees.
Targeted Upregulation of FMRP Expression as an Approach to the Treatment of Fragile X Syndrome
2015-08-01
form of autism, and a relatively common cause of epilepsy . The syndrome is caused by partial or complete silencing of the fragile X (FMR1) gene when...potential to correct ALL of the clinical domains of fragile X syndrome, including epilepsy -like activity observed for both those with FXS and carriers of...the FMR1 gene. 15. SUBJECT TERMS Fragile X, autism, FMR1, FXTAS, CGG repeat, epilepsy , seizures, FMRP, PTSD, premutation, iPSC, progenitor, calcium
Neurosteroids Reverse Tonic Inhibition Deficits in Fragile X Syndrome
2017-10-01
AWARD NUMBER: W81XWH-15-1-0190 TITLE: Neurosteroids Reverse Tonic Inhibition Deficits in Fragile X Syndrome PRINCIPAL INVESTIGATOR: Dr...14 July 2017 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Neurosteroids Reverse Tonic Inhibition Deficits in Fragile X Syndrome 5b. GRANT NUMBER...18 9. Appendices……………………………………………………………18 2 1. Introduction Fragile X syndrome (FXS) is the most common form of inherited
Fabric-based alkaline direct formate microfluidic fuel cells.
Domalaon, Kryls; Tang, Catherine; Mendez, Alex; Bernal, Franky; Purohit, Krutarth; Pham, Linda; Haan, John; Gomez, Frank A
2017-04-01
Fabric-based microfluidic fuel cells (MFCs) serve as a novel, cost-efficient alternative to traditional FCs and batteries, since fluids naturally travel across fabric via capillary action, eliminating the need for an external pump and lowering production and operation costs. Building on previous research with Y-shaped paper-based MFCs, fabric-based MFCs mitigate fragility and durability issues caused by long periods of fuel immersion. In this study, we describe a microfluidic fabric-based direct formate fuel cell, with 5 M potassium formate and 30% hydrogen peroxide as the anode fuel and cathode oxidant, respectively. Using a two-strip, stacked design, the optimized parameters include the type of encasement, the barrier, and the fabric type. Surface contact of the fabric and laminate sheet expedited flow and respective chemical reactions. The maximum current (22.83 mA/cm 2 ) and power (4.40 mW/cm 2 ) densities achieved with a 65% cotton/35% polyester blend material are a respective 8.7% and 32% higher than previous studies with Y-shaped paper-based MFCs. In series configuration, the MFCs generate sufficient energy to power a handheld calculator, a thermometer, and a spectrum of light-emitting diodes. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Repeat-mediated genetic and epigenetic changes at the FMR1 locus in the Fragile X-related disorders
Usdin, Karen; Hayward, Bruce E.; Kumari, Daman; Lokanga, Rachel A.; Sciascia, Nicholas; Zhao, Xiao-Nan
2014-01-01
The Fragile X-related disorders are a group of genetic conditions that include the neurodegenerative disorder, Fragile X-associated tremor/ataxia syndrome (FXTAS), the fertility disorder, Fragile X-associated primary ovarian insufficiency (FXPOI) and the intellectual disability, Fragile X syndrome (FXS). The pathology in all these diseases is related to the number of CGG/CCG-repeats in the 5′ UTR of the Fragile X mental retardation 1 (FMR1) gene. The repeats are prone to continuous expansion and the increase in repeat number has paradoxical effects on gene expression increasing transcription on mid-sized alleles and decreasing it on longer ones. In some cases the repeats can simultaneously both increase FMR1 mRNA production and decrease the levels of the FMR1 gene product, Fragile X mental retardation 1 protein (FMRP). Since FXTAS and FXPOI result from the deleterious consequences of the expression of elevated levels of FMR1 mRNA and FXS is caused by an FMRP deficiency, the clinical picture is turning out to be more complex than once appreciated. Added complications result from the fact that increasing repeat numbers make the alleles somatically unstable. Thus many individuals have a complex mixture of different sized alleles in different cells. Furthermore, it has become apparent that the eponymous fragile site, once thought to be no more than a useful diagnostic criterion, may have clinical consequences for females who inherit chromosomes that express this site. This review will cover what is currently known about the mechanisms responsible for repeat instability, for the repeat-mediated epigenetic changes that affect expression of the FMR1 gene, and for chromosome fragility. It will also touch on what current and future options are for ameliorating some of these effects. PMID:25101111
Rescue of Synaptic Phenotypes and Spatial Memory in Young Fragile X Mice.
Sun, Miao-Kun; Hongpaisan, Jarin; Alkon, Daniel L
2016-05-01
Fragile X syndrome (FXS) is characterized by synaptic immaturity, cognitive impairment, and behavioral changes. The disorder is caused by transcriptional shutdown in neurons of thefragile X mental retardation 1gene product, fragile X mental retardation protein. Fragile X mental retardation protein is a repressor of dendritic mRNA translation and its silencing leads to dysregulation of synaptically driven protein synthesis and impairments of intellect, cognition, and behavior, and FXS is a disorder that currently has no effective therapeutics. Here, young fragile X mice were treated with chronic bryostatin-1, a relatively selective protein kinase Cεactivator, which induces synaptogenesis and synaptic maturation/repair. Chronic treatment with bryostatin-1 rescues young fragile X mice from the disorder phenotypes, including normalization of most FXS abnormalities in 1) hippocampal brain-derived neurotrophic factor expression, 2) postsynaptic density-95 levels, 3) transformation of immature dendritic spines to mature synapses, 4) densities of the presynaptic and postsynaptic membranes, and 5) spatial learning and memory. The therapeutic effects were achieved without downregulation of metabotropic glutamate receptor (mGluR) 5 in the hippocampus and are more dramatic than those of a late-onset treatment in adult fragile X mice. mGluR5 expression was in fact lower in fragile X mice and its expression was restored with the bryostatin-1 treatment. Our results show that synaptic and cognitive function of young FXS mice can be normalized through pharmacological treatment without downregulation of mGluR5 and that bryostatin-1-like agents may represent a novel class of drugs to treat fragile X mental retardation at a young age and in adults. Copyright © 2016 by The American Society for Pharmacology and Experimental Therapeutics.
Sawicka, Kirsty; Pyronneau, Alexander; Chao, Miranda; Bennett, Michael V L; Zukin, R Suzanne
2016-10-11
Fragile X syndrome (FXS) is the most common heritable cause of intellectual disability and a leading genetic form of autism. The Fmr1 KO mouse, a model of FXS, exhibits elevated translation in the hippocampus and the cortex. ERK (extracellular signal-regulated kinase) and mTOR (mechanistic target of rapamycin) signaling regulate protein synthesis by activating downstream targets critical to translation initiation and elongation and are known to contribute to hippocampal defects in fragile X. Here we show that the effect of loss of fragile X mental retardation protein (FMRP) on these pathways is brain region specific. In contrast to the hippocampus, ERK (but not mTOR) signaling is elevated in the neocortex of fragile X mice. Phosphorylation of ribosomal protein S6, typically a downstream target of mTOR, is elevated in the neocortex, despite normal mTOR activity. This is significant in that S6 phosphorylation facilitates translation, correlates with neuronal activation, and is altered in neurodevelopmental disorders. We show that in fragile X mice, S6 is regulated by ERK via the "alternative" S6 kinase p90-ribosomal S6 kinase (RSK), as evidenced by the site of elevated phosphorylation and the finding that ERK inhibition corrects elevated RSK and S6 activity. These findings indicate that signaling networks are altered in the neocortex of fragile X mice such that S6 phosphorylation receives aberrant input from ERK/RSK. Importantly, an RSK inhibitor reduces susceptibility to audiogenic seizures in fragile X mice. Our findings identify RSK as a therapeutic target for fragile X and suggest the therapeutic potential of drugs for the treatment of FXS may vary in a brain-region-specific manner.
Advances in the Treatment of Fragile X Syndrome
Hagerman, Randi J.; Berry-Kravis, Elizabeth; Kaufmann, Walter E.; Ono, Michele Y.; Tartaglia, Nicole; Lachiewicz, Ave; Kronk, Rebecca; Delahunty, Carol; Hessl, David; Visootsak, Jeannie; Picker, Jonathan; Gane, Louise; Tranfaglia, Michael
2010-01-01
The FMR1 mutations can cause a variety of disabilities, including cognitive deficits, attention-deficit/hyperactivity disorder, autism, and other socioemotional problems, in individuals with the full mutation form (fragile X syndrome) and distinct difficulties, including primary ovarian insufficiency, neuropathy and the fragile X-associated tremor/ataxia syndrome, in some older premutation carriers. Therefore, multigenerational family involvement is commonly encountered when a proband is identified with a FMR1 mutation. Studies of metabotropic glutamate receptor 5 pathway antagonists in animal models of fragile X syndrome have demonstrated benefits in reducing seizures, improving behavior, and enhancing cognition. Trials of metabotropic glutamate receptor 5 antagonists are beginning with individuals with fragile X syndrome. Targeted treatments, medical and behavioral interventions, genetic counseling, and family supports are reviewed here. PMID:19117905
Global Identification of Disease Associated Genes in Fragile X Cells
2016-08-01
for this study listed as follows: 1) Validate the co-localized R-loop formation and chromosome fragility in Fragile X cells, particularly at the brain ...retardation protein February 2016, NGS Data Analysis & Informatics Conference, San Diego, California (Poster presentation) Title: Global detection
Reversing the Effects of Fragile X Syndrome
ERIC Educational Resources Information Center
Ogren, Marilee P.; Lombroso, Paul J.
2008-01-01
A research on how synaptic plasticity is abnormally regulated in fragile X syndrome and how this abnormality can be reversed by therapeutic interventions is presented. Fragile X syndrome is a disorder of synaptic plasticity that contributes to abnormal development and interferes with normal learning and memory.
Resolution of spatial and temporal visual attention in infants with fragile X syndrome.
Farzin, Faraz; Rivera, Susan M; Whitney, David
2011-11-01
Fragile X syndrome is the most common cause of inherited intellectual impairment and the most common single-gene cause of autism. Individuals with fragile X syndrome present with a neurobehavioural phenotype that includes selective deficits in spatiotemporal visual perception associated with neural processing in frontal-parietal networks of the brain. The goal of the current study was to examine whether reduced resolution of spatial and/or temporal visual attention may underlie perceptual deficits related to fragile X syndrome. Eye tracking was used to psychophysically measure the limits of spatial and temporal attention in infants with fragile X syndrome and age-matched neurotypically developing infants. Results from these experiments revealed that infants with fragile X syndrome experience drastically reduced resolution of temporal attention in a genetic dose-sensitive manner, but have a spatial resolution of attention that is not impaired. Coarse temporal attention could have significant knock-on effects for the development of perceptual, cognitive and motor abilities in individuals with the disorder.
Resolution of spatial and temporal visual attention in infants with fragile X syndrome
Rivera, Susan M.; Whitney, David
2011-01-01
Fragile X syndrome is the most common cause of inherited intellectual impairment and the most common single-gene cause of autism. Individuals with fragile X syndrome present with a neurobehavioural phenotype that includes selective deficits in spatiotemporal visual perception associated with neural processing in frontal–parietal networks of the brain. The goal of the current study was to examine whether reduced resolution of spatial and/or temporal visual attention may underlie perceptual deficits related to fragile X syndrome. Eye tracking was used to psychophysically measure the limits of spatial and temporal attention in infants with fragile X syndrome and age-matched neurotypically developing infants. Results from these experiments revealed that infants with fragile X syndrome experience drastically reduced resolution of temporal attention in a genetic dose-sensitive manner, but have a spatial resolution of attention that is not impaired. Coarse temporal attention could have significant knock-on effects for the development of perceptual, cognitive and motor abilities in individuals with the disorder. PMID:22075522
Degraded speech sound processing in a rat model of fragile X syndrome
Engineer, Crystal T.; Centanni, Tracy M.; Im, Kwok W.; Rahebi, Kimiya C.; Buell, Elizabeth P.; Kilgard, Michael P.
2014-01-01
Fragile X syndrome is the most common inherited form of intellectual disability and the leading genetic cause of autism. Impaired phonological processing in fragile X syndrome interferes with the development of language skills. Although auditory cortex responses are known to be abnormal in fragile X syndrome, it is not clear how these differences impact speech sound processing. This study provides the first evidence that the cortical representation of speech sounds is impaired in Fmr1 knockout rats, despite normal speech discrimination behavior. Evoked potentials and spiking activity in response to speech sounds, noise burst trains, and tones were significantly degraded in primary auditory cortex, anterior auditory field and the ventral auditory field. Neurometric analysis of speech evoked activity using a pattern classifier confirmed that activity in these fields contains significantly less information about speech sound identity in Fmr1 knockout rats compared to control rats. Responses were normal in the posterior auditory field, which is associated with sound localization. The greatest impairment was observed in the ventral auditory field, which is related to emotional regulation. Dysfunction in the ventral auditory field may contribute to poor emotional regulation in fragile X syndrome and may help explain the observation that later auditory evoked responses are more disturbed in fragile X syndrome compared to earlier responses. Rodent models of fragile X syndrome are likely to prove useful for understanding the biological basis of fragile X syndrome and for testing candidate therapies. PMID:24713347
ERIC Educational Resources Information Center
Schwarte, Andrea R.
2008-01-01
This article provides an overview of current research on Fragile X Syndrome, and how that knowledge can be used to guide successful intervention. The genetic etiology of Fragile X is reviewed and the physical, cognitive, adaptive, behavioral, and emotional phenotypes of children with the disorder are described, highlighting the differences in…
Ungprasert, P; Crowson, C S; Matteson, E L
2018-05-01
Incidence of fragility fracture of a population-based cohort of 345 patients with sarcoidosis was compared with age- and sex-matched comparators. The incidence of fragility fracture was higher among patients with sarcoidosis with a hazard ratio (HR) of 2.18.
Newborn Screening for Fragile X Syndrome
ERIC Educational Resources Information Center
Bailey, Donald B., Jr.
2004-01-01
Newborn screening for fragile X syndrome (FXS) is technically possible, and in the relatively near future accurate and inexpensive screening technologies are likely to be available. When that happens, will America's public health system adopt newborn screening for fragile X syndrome? This article addresses this issue by first placing screening for…
Dopamine transporter imaging study in parkinsonism occurring in fragile X premutation carriers.
Ceravolo, R; Antonini, A; Volterrani, D; Rossi, C; Goldwurm, S; Di Maria, E; Kiferle, L; Bonuccelli, U; Murri, L
2005-12-27
The authors studied four patients with parkinsonism carrying the fragile X premutation using SPECT with ([23)I]FP-CIT. They found evidence of preserved presynaptic nigrostriatal function, suggesting that parkinsonism in the X fragile premutation might be related to postsynaptic dopaminergic changes or different neurotransmitter alterations.
A Broader Definition of Fragility: The Communities and Schools of Brazil's "Favelas"
ERIC Educational Resources Information Center
Straubhaar, Rolf
2012-01-01
Though the existing literature on the "favelas" (or shantytowns) of Brazil thoroughly documents the chaotic and violent nature of life within them, few connections have been made between the literature on "favelas", fragility and small states, particularly with regard to the fragile state of educational institutions in…
The Medically Fragile Child in the School Setting. Second Edition.
ERIC Educational Resources Information Center
American Federation of Teachers, Washington, DC.
This guide for teachers whose classes include a medically fragile child considers roles and responsibilities of teachers with these students, teachers' rights as school employees, and possible solutions and protections for local unions to pursue. Chapter 1 provides an overview. It defines "medically fragile," summarizes legal…
Attentional Set-Shifting in Fragile X Syndrome
ERIC Educational Resources Information Center
Van der Molen, M. J. W.; Van der Molen, M. W.; Ridderinkhof, K. R.; Hamel, B. C. J.; Curfs, L. M. G.; Ramakers, G. J. A.
2012-01-01
The ability to flexibly adapt to the changing demands of the environment is often reported as a core deficit in fragile X syndrome (FXS). However, the cognitive processes that determine this attentional set-shifting deficit remain elusive. The present study investigated attentional set-shifting ability in fragile X syndrome males with the…
Academic Skills of Boys With Fragile X Syndrome: Profiles and Predictors
ERIC Educational Resources Information Center
Roberts, Jane E.; Schaaf, Jennifer M.; Skinner, Martie; Wheeler, Anne; Hooper, Stephen; Hatton, Deborah D.; Bailey, Donald B., Jr.
2005-01-01
The academic achievement of boys with fragile X syndrome and the relation between several predictive factors and academic performance are reported. Boys with fragile X syndrome displayed significant deficits in all academic skill areas. Relative strengths were observed in general knowledge, reflecting the ability to integrate experiential…
Speech Fluency in Fragile X Syndrome
ERIC Educational Resources Information Center
Van Borsel, John; Dor, Orianne; Rondal, Jean
2008-01-01
The present study investigated the dysfluencies in the speech of nine French speaking individuals with fragile X syndrome. Type, number, and loci of dysfluencies were analysed. The study confirms that dysfluencies are a common feature of the speech of individuals with fragile X syndrome but also indicates that the dysfluency pattern displayed is…
Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS)
ERIC Educational Resources Information Center
Hagerman, Paul J.; Hagerman, Randi J.
2004-01-01
Carriers of fragile X mental retardation 1 ("FMR1") premutation alleles (55 to 200 CGG repeats) are generally spared the more serious neurodevelopmental problems associated with the full-mutation carriers (greater than 200 repeats) of fragile X syndrome. However, some adult male premutation carriers (55-200 repeats) develop a neurological syndrome…
Neurosteroids Reverse Tonic Inhibition Deficits in Fragile X Syndrome
2016-08-01
AWARD NUMBER: W81XWH-15-1-0190 TITLE: Neurosteroids Reverse Tonic Inhibition Deficits in Fragile X Syndrome PRINCIPAL INVESTIGATOR: Dr. Paul...AND SUBTITLE 5a. CONTRACT NUMBER Neurosteroids Reverse Tonic Inhibition Deficits in Fragile X Syndrome 5b. GRANT NUMBER 5c. PROGRAM ELEMENT...Appendices……………………………………………………………11 2 1. Introduction Fragile X syndrome (FXS) is the most common form of inherited intellectual disability. In addition
Reanalysis of the fragility of glycerol at very high pressures using new Tg data
NASA Astrophysics Data System (ADS)
Lyon, Kevin; Oliver, William
Direct measurements of the glass transition temperature of glycerol between 1 atm and 6.7 GPa from our lab allow reanalysis of high-pressure viscosity data, which were limited to approximately 107 poise. Previous attempts to determine Tg (P) and fragility by extrapolation of the viscosity data by many orders of magnitude led to inconclusive results. Tg (P) data constrain the value of viscosity at the glass transition providing for more accurate determinations of isobaric fragilities. Over most of the pressure range, a constant fragility is found in agreement with analysis of high-pressure dielectric data by Paluch et al.. Discrepancies in the pressure dependence of the fragility of glycerol at very low pressures exist in the literature and will also be discussed.
Greenberg, Jan; Seltzer, Marsha; Baker, Jason; Smith, Leann; Warren, Steven F; Brady, Nancy; Hong, Jinkuk
2012-07-01
We examine how the family environment is associated with aspects of the Fragile X syndrome phenotype during childhood, adolescence, and adulthood. Mothers of children (n = 48), adolescents (n = 85), and adults (n = 34) with Fragile X syndrome participated in a multisite study. For children and adults with Fragile X syndrome, the presence of warmth and positivity and the absence of criticism were associated with fewer behavior problems. Although a higher level of criticism was significantly associated with greater behavior problems, there were only trend-level associations between levels of warmth and positivity and behavior problems during the adolescent years. The provision of family psychoeducation programs, which can reduce parental criticism, would likely benefit both the individual with Fragile X syndrome and the family.
Greenberg, Jan S.; Seltzer, Marsha Mailick; Baker, Jason K.; Smith, Leann E.; Warren, Steven F.; Brady, Nancy; Hong, Jinkuk
2012-01-01
We examine how the family environment is associated with aspects of the Fragile X syndrome phenotype during childhood, adolescence, and adulthood. Mothers of children (n = 48), adolescents (n = 85), and adults (n = 34) with Fragile X syndrome participated in a multisite study. For children and adults with Fragile X syndrome, the presence of warmth and positivity and the absence of criticism were associated with fewer behavior problems. Although a higher level of criticism was significantly associated with greater behavior problems, there were only trend-level associations between levels of warmth and positivity and behavior problems during the adolescent years. The provision of family psychoeducation programs, which can reduce parental criticism, would likely benefit both the individual with Fragile X syndrome and the family. PMID:22809078
Manipulations of attention dissociate fragile visual short-term memory from visual working memory.
Vandenbroucke, Annelinde R E; Sligte, Ilja G; Lamme, Victor A F
2011-05-01
People often rely on information that is no longer in view, but maintained in visual short-term memory (VSTM). Traditionally, VSTM is thought to operate on either a short time-scale with high capacity - iconic memory - or a long time scale with small capacity - visual working memory. Recent research suggests that in addition, an intermediate stage of memory in between iconic memory and visual working memory exists. This intermediate stage has a large capacity and a lifetime of several seconds, but is easily overwritten by new stimulation. We therefore termed it fragile VSTM. In previous studies, fragile VSTM has been dissociated from iconic memory by the characteristics of the memory trace. In the present study, we dissociated fragile VSTM from visual working memory by showing a differentiation in their dependency on attention. A decrease in attention during presentation of the stimulus array greatly reduced the capacity of visual working memory, while this had only a small effect on the capacity of fragile VSTM. We conclude that fragile VSTM is a separate memory store from visual working memory. Thus, a tripartite division of VSTM appears to be in place, comprising iconic memory, fragile VSTM and visual working memory. Copyright © 2011 Elsevier Ltd. All rights reserved.
Lieb-Lundell, Cornelia C E
2016-11-01
Fragile X syndrome (FXS) is the first of 3 syndromes identified as a health condition related to fragile X mental retardation (FMR1) gene dysfunction. The other 2 syndromes are fragile X-associated primary ovarian insufficiency syndrome (FXPOI) and fragile X-associated tremor/ataxia syndrome (FXTAS), which together are referred to as fragile X-associated disorders (FXDs). Collectively, this group comprises the 3 faces of fragile X. Even though the 3 conditions share a common genetic defect, each one is a separate health condition that results in a variety of body function impairments such as motor delay, musculoskeletal issues related to low muscle tone, coordination limitations, ataxia, tremor, undefined muscle aches and pains, and, for FXTAS, a late-onset neurodegeneration. Although each FXD condition may benefit from physical therapy intervention, available evidence as to the efficacy of intervention appropriate to FXDs is lacking. This perspective article will discuss the genetic basis of FMR1 gene dysfunction and describe health conditions related to this mutation, which have a range of expressions within a family. Physical therapy concerns and possible assessment and intervention strategies will be introduced. Understanding the intergenerational effect of the FMR1 mutation with potential life-span expression is a key component to identifying and treating the health conditions related to this specific genetic condition. © 2016 American Physical Therapy Association.
Freedenberg, D L; Gane, L W; Richards, C S; Lampe, M; Hills, J; O'Connor, R; Manchester, D; Taylor, A; Tassone, F; Hulseberg, D; Hagerman, R J; Patil, S R
1999-07-30
We report on an individual with developmental delays, short stature, skeletal abnormalities, normal pubertal development, expansion of the fragile X triplet repeat, as well as an isodicentric X chromosome. S is a 19-year-old woman who presented for evaluation of developmental delay. Pregnancy was complicated by a threatened miscarriage. She was a healthy child with intellectual impairment noted in infancy. Although she had global delays, speech was noted to be disproportionately delayed with few words until age 3.5 years. Facial appearance was consistent with fragile X syndrome. Age of onset of menses was 11 years with normal breast development. A maternal male second cousin had been identified with fragile X syndrome based on DNA studies. The mother of this child (S's maternal first cousin) and the grandfather (S's maternal uncle) were both intellectually normal but were identified as carrying triplet expansions in the premutation range. S's mother had some school difficulties but was not identified as having global delays. Molecular analysis of S's fragile X alleles noted an expansion of more than 400 CGG repeats in one allele. Routine cytogenetic studies of peripheral blood noted the presence of an isodicentric X in 81of 86 cells scored. Five of 86 cells were noted to be 45,X. Cytogenetic fra(X) studies from peripheral blood showed that the structurally normal chromosome had the fragile site in approximately 16% of the cells. Analysis of maternal fragile X alleles identified an allele with an expansion to approximately 110 repeats. FMRP studies detected the expression of the protein in 24% of cells studied. To our knowledge, this is the first patient reported with an isodicentric X and fragile X syndrome. Whereas her clinical phenotype is suggestive of fragile X syndrome, her skeletal abnormalities may represent the presence of the isodicentric X. Treatment of S with 20 mg/day of Prozac improved her behavior. In the climate of cost con trol, this individual reinforces the recommendation of obtaining chromosomes on individuals with developmental delay even with a family history of fragile X syndrome. Copyright 1999 Wiley-Liss, Inc.
Why many polymers are so fragile: A new perspective
Dalle-Ferrier, C.; Kisliuk, A.; Hong, L.; ...
2016-10-21
Many polymers exhibit much steeper temperature dependence of their structural relaxation time (higher fragility) than liquids of small molecules, and the mechanism of this unusually high fragility in polymers remains a puzzle. To reveal additional hints for understanding the underlying mechanism, we analyzed correlation of many properties of polymers to their fragility on example of model polymer polystyrene with various molecular weights (MWs). Here, we demonstrate that these correlations work for short chains (oligomers), but fail progressively with increase in MW. Our surprising discovery is that the steepness of the temperature dependence (fragility) of the viscosity that is determined bymore » chain relaxation follows the correlations at all molecular weights. These results suggest that the molecular level relaxation still follows the behavior usual for small molecules even in polymers, and its fragility (chain fragility) falls in the range usual for molecular liquids. It is the segmental relaxation that has this unusually high fragility. We also speculate that many polymers cannot reach an ergodic state on the time scale of segmental dynamics due to chain connectivity and rigidity. This leads to sharper decrease in accessible configurational entropy upon cooling and results in steeper temperature dependence of segmental relaxation. Our proposed scenario provides a new important insight into the specifics of polymer dynamics: the role of ergodicity time and length scale. At the end, we suggest that a similar scenario can be applicable also to other molecular systems with slow intra-molecular degrees of freedom and to chemically complex systems where the time scale of chemical fluctuations can be longer than the time scale of structural relaxation.« less
Why many polymers are so fragile: A new perspective
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dalle-Ferrier, C.; Kisliuk, A.; Hong, L.
Many polymers exhibit much steeper temperature dependence of their structural relaxation time (higher fragility) than liquids of small molecules, and the mechanism of this unusually high fragility in polymers remains a puzzle. To reveal additional hints for understanding the underlying mechanism, we analyzed correlation of many properties of polymers to their fragility on example of model polymer polystyrene with various molecular weights (MWs). Here, we demonstrate that these correlations work for short chains (oligomers), but fail progressively with increase in MW. Our surprising discovery is that the steepness of the temperature dependence (fragility) of the viscosity that is determined bymore » chain relaxation follows the correlations at all molecular weights. These results suggest that the molecular level relaxation still follows the behavior usual for small molecules even in polymers, and its fragility (chain fragility) falls in the range usual for molecular liquids. It is the segmental relaxation that has this unusually high fragility. We also speculate that many polymers cannot reach an ergodic state on the time scale of segmental dynamics due to chain connectivity and rigidity. This leads to sharper decrease in accessible configurational entropy upon cooling and results in steeper temperature dependence of segmental relaxation. Our proposed scenario provides a new important insight into the specifics of polymer dynamics: the role of ergodicity time and length scale. At the end, we suggest that a similar scenario can be applicable also to other molecular systems with slow intra-molecular degrees of freedom and to chemically complex systems where the time scale of chemical fluctuations can be longer than the time scale of structural relaxation.« less
Aberrant face and gaze habituation in fragile x syndrome.
Bruno, Jennifer Lynn; Garrett, Amy S; Quintin, Eve-Marie; Mazaika, Paul K; Reiss, Allan L
2014-10-01
The authors sought to investigate neural system habituation to face and eye gaze in fragile X syndrome, a disorder characterized by eye-gaze aversion, among other social and cognitive deficits. Participants (ages 15-25 years) were 30 individuals with fragile X syndrome (females, N=14) and a comparison group of 25 individuals without fragile X syndrome (females, N=12) matched for general cognitive ability and autism symptoms. Functional MRI (fMRI) was used to assess brain activation during a gaze habituation task. Participants viewed repeated presentations of four unique faces with either direct or averted eye gaze and judged the direction of eye gaze. Four participants (males, N=4/4; fragile X syndrome, N=3) were excluded because of excessive head motion during fMRI scanning. Behavioral performance did not differ between the groups. Less neural habituation (and significant sensitization) in the fragile X syndrome group was found in the cingulate gyrus, fusiform gyrus, and frontal cortex in response to all faces (direct and averted gaze). Left fusiform habituation in female participants was directly correlated with higher, more typical levels of the fragile X mental retardation protein and inversely correlated with autism symptoms. There was no evidence for differential habituation to direct gaze compared with averted gaze within or between groups. Impaired habituation and accentuated sensitization in response to face/eye gaze was distributed across multiple levels of neural processing. These results could help inform interventions, such as desensitization therapy, which may help patients with fragile X syndrome modulate anxiety and arousal associated with eye gaze, thereby improving social functioning.
Inaba, Yoshimi; Herlihy, Amy S; Schwartz, Charles E; Skinner, Cindy; Bui, Quang M; Cobb, Joanna; Shi, Elva Z; Francis, David; Arvaj, Alison; Amor, David J; Pope, Kate; Wotton, Tiffany; Cohen, Jonathan; Hewitt, Jacqueline K; Hagerman, Randi J; Metcalfe, Sylvia A; Hopper, John L; Loesch, Danuta Z; Slater, Howard R; Godler, David E
2013-04-01
We show that a novel fragile X-related epigenetic element 2 FMR1 methylation test can be used along with a test for sex-determining region Y (SRY) to provide the option of combined fragile X syndrome and sex chromosome aneuploidy newborn screening. Fragile X-related epigenetic element 2, SRY, and FMR1 CGG repeat analyses were performed on blood and saliva DNA, and in adult and newborn blood spots. The cohort consisted of 159 controls (CGG <40), 187 premutation (CGG 56-170), and 242 full-mutation (CGG ~200-2,000) males and females, 106 sex chromosome aneuploidy individuals, and 151 cytogenetically normal controls. At the 0.435 threshold, fragile X-related epigenetic element 2 analysis in males was robust on both blood DNA and newborn blood spots, with specificity and sensitivity of ~100% for full-mutation genotype. In females, the specificity was 99%, whereas half of full-mutation females were above the 0.435 threshold in both blood DNA and newborn blood spots. Furthermore, at this threshold, the test could not differentiate individuals with Klinefelter syndrome from female controls without using the SRY marker. When combined with SRY analysis, the test was consistent with most results for sex chromosome aneuploidies from karyotyping. Setting specific thresholds for fragile X-related epigenetic element 2 analysis and including the SRY marker provides the option to either include or exclude detection of sex chromosome aneuploidies as part of fragile X syndrome newborn screening.
Finiteness Marking in Boys with Fragile X Syndrome
ERIC Educational Resources Information Center
Sterling, Audra M.; Rice, Mabel L.; Warren, Steven F.
2012-01-01
Purpose: The current study investigated finiteness marking (e.g., he walk "s", he walk "ed") in boys with fragile X syndrome (FXS); the boys were grouped based on receptive vocabulary (i.e., borderline, impaired). Method: Twenty-one boys with the full mutation of fragile X, between the ages of 8 and 16 years participated. The…
International Fragile X Conference Proceedings (3rd, Snowmass/Aspen, Colorado, 1992).
ERIC Educational Resources Information Center
Hagerman, Randi Jenssen, Ed.; McKenzie, Pamela, Ed.
This proceedings document presents the texts or summaries of 52 papers given at a 1992 conference on Fragile X syndrome. Preliminary information includes names and institutional affiliations of conference faculty, information about the National Fragile X Foundation, awards presented at the conference, and a list of resource centers (by state).…
Behavioral Intervention for Problem Behavior in Children with Fragile X Syndrome
ERIC Educational Resources Information Center
Moskowitz, Lauren J.; Carr, Edward G.; Durand, V. Mark
2011-01-01
Parents and professionals typically report problem behavior as a significant concern for children with fragile X syndrome. In the present study, the authors explored whether behaviorally based interventions would result in a reduction in problem behavior and an improvement in quality of life for 3 children with fragile X syndrome and their…
Examining the Function of Problem Behavior in Fragile X Syndrome: Preliminary Experimental Analysis
ERIC Educational Resources Information Center
Langthorne, Paul; McGill, Peter; O'Reilly, Mark F.; Lang, Russell; Machalicek, Wendy; Chan, Jeffrey Michael; Rispoli, Mandy
2011-01-01
Fragile X syndrome is the most common inherited cause of intellectual and developmental disability. The influence of environmental variables on behaviors associated with the syndrome has received only scant attention. The current study explored the function served by problem behavior in fragile X syndrome by using experimental functional analysis…
Memory Skills of Boys with Fragile X Syndrome
ERIC Educational Resources Information Center
Ornstein, Peter A.; Schaaf, Jennifer M.; Hooper, Stephen R.; Hatton, Deborah D.; Mirrett, Penny; Bailey, Donald B., Jr.
2008-01-01
Multiple aspects of memory were examined in 42 boys with fragile X syndrome and a comparison group of 42 typically developing boys matched on MA. Working memory, incidental memory, and deliberate memory were assessed with a battery that included both free-recall and recognition tasks. Findings indicated that boys with fragile X syndrome performed…
Fragile X Syndrome in Males: Diagnostic, Behavioral, and Educational Implications.
ERIC Educational Resources Information Center
Bellinger, Diane; And Others
This paper reviews the research on fragile X syndrome, the second most common cause of mental retardation related to chromosomal anomaly. It notes that far more males than females are affected by the fragile X syndrome, which typically results in craniofacial changes, delays in growth and development, speech/language difficulties, and cognitive…
Resolution of Spatial and Temporal Visual Attention in Infants with Fragile X Syndrome
ERIC Educational Resources Information Center
Farzin, Faraz; Rivera, Susan M.; Whitney, David
2011-01-01
Fragile X syndrome is the most common cause of inherited intellectual impairment and the most common single-gene cause of autism. Individuals with fragile X syndrome present with a neurobehavioural phenotype that includes selective deficits in spatiotemporal visual perception associated with neural processing in frontal-parietal networks of the…
Fragile X Syndrome. Early Developments. Volume 8, Number 2, Summer 2004
ERIC Educational Resources Information Center
Manuel, John
2004-01-01
Eleven years ago, FPG Child Development Institute (FPG) launched a longitudinal study of a little known form of mental retardation known as fragile X syndrome (FXS). The Carolina Fragile X Project has since grown into a multidisciplinary team studying diverse aspects of the condition, ranging from early identification to school performance. The…
Visual Pathway Deficit in Female Fragile X Premutation Carriers: A Potential Endophenotype
ERIC Educational Resources Information Center
Keri, Szabolcs; Benedek, Gyorgy
2009-01-01
Previous studies indicated impaired magnocellular (M) and relatively spared parvocellular (P) visual pathway functioning in patients with fragile X syndrome. In this study, we assessed M and P pathways in 22 female fragile X premutation carriers with normal intelligence and in 20 healthy non-carrier controls. Testing procedure included visual…
Management of Medically Fragile Infants.
ERIC Educational Resources Information Center
Ueda, Dawn; Caulfield, Rick
2001-01-01
Discusses the role of the Child Life Specialist in helping to meet the special needs of medically fragile children. Argues that since many child care professionals may come into contact with medically fragile children at some point in their careers, it is important to examine child life as a specialization in the health care profession. (SD)
Ocular Motor Indicators of Executive Dysfunction in Fragile X and Turner Syndromes
ERIC Educational Resources Information Center
Lasker, Adrian G.; Mazzocco, Michele M. M.; Zee, David S.
2007-01-01
Fragile X and Turner syndromes are two X-chromosome-related disorders associated with executive function and visual spatial deficits. In the present study, we used ocular motor paradigms to examine evidence that disruption to different neurological pathways underlies these deficits. We tested 17 females with fragile X, 19 females with Turner…
An Investigation of Narrative Ability in Boys with Autism and Fragile X Syndrome
ERIC Educational Resources Information Center
Hogan-Brown, Abigail L.; Losh, Molly; Martin, Gary E.; Mueffelmann, Deborah J.
2013-01-01
Whereas pragmatic language difficulties are characteristic of both autism and Fragile X syndrome, it is unclear whether such deficits are qualitatively similar or whether certain skills are differentially affected. This study compared narrative competence in boys with autism, Fragile X syndrome, Down syndrome, and typical development. Results…
Social Behavior and Cortisol Reactivity in Children with Fragile X Syndrome
ERIC Educational Resources Information Center
Hessl, David; Glaser, Bronwyn; Dyer-Friedman, Jennifer; Reiss, Allan L.
2006-01-01
Objective: To examine the association between limbic-hypothalamic-pituitary-adrenal (L-HPA) axis reactivity and social behavior in children with fragile X syndrome (FXS). Method: Salivary cortisol changes and concurrent anxiety-related behaviors consistent with the behavioral phenotype of FXS were measured in 90 children with the fragile X full…
NASA Astrophysics Data System (ADS)
Saini, Manoj K.; Jin, Xiao; Wu, Tao; Liu, Yingdan; Wang, Li-Min
2018-03-01
We have investigated the enthalpic and dielectric relaxations of four groups of quinoline analogs having similar structural properties (i.e., rigidity, stiffness, and bulkiness) but a different steric character and the nature of intermolecular interactions and flexibility. The dielectric fragility index (md) and the enthalpic one (mH), determined by the Tool-Narayanaswamy-Moynihan-Hodge formalism, are comparable. Generally, for the four sets of molecules of similar structures, both the interactions and flexibility are found to be critical in making the large span of fragility (i.e., from 59 to 131) and glass forming ability. By contrast, individual impacts of the interaction and flexibility can only explain fragility partly among each group of isomers. We found that the molecules with high fragility are of relatively low liquid density, reflecting the joint impact of the interactions and flexibility. An interesting result is observed among the isomers that the molecules which are fragile have enhanced glass forming ability. The results are unveiling the joint impacts of molecular structure (flexibility) and intermolecular interaction on the molecular dynamics.
Howell, Peter
2008-02-01
Van Borsel, Dor, and Rondal (2007) examined the speech of seven boys and two young male adults with fragile X syndrome and considered whether their speech was comparable to that reported in the developmental stuttering literature. They listed five criteria which led them to conclude that the speech patterns of speakers with fragile X syndrome differed from those observed in developmental stuttering. The differences noted were: 1) distribution of type of dysfluency; 2) the class of word on which dysfluency occurred; 3) whether word length affected dysfluency; 4) number of times words and phrases were repeated; and 5) whether there were influences of material type on fluency (spontaneous speech, repeated material etc.). They concluded that the speech of speakers with fragile X syndrome differed from developmental stuttering. The comparisons that van Borsel et al. (2007) made between participant groups were not for speakers of comparable ages. Comparisons with groups of corresponding ages support the opposite conclusion, namely the young speakers with fragile X syndrome show patterns similar to developmental stuttering.
Fragility of chalcogenide glass in relation to characteristic temperature T0/Tg
NASA Astrophysics Data System (ADS)
Shaker, A. M.; Shanker Rao, T.; Lilly Shanker Rao, T.; Venkataraman, K.
2018-03-01
The present study reports the mutual relationship between the fragility index m and the characteristic temperature T0/Tg. The fragility of the chalcogenide amorphous glass of Ge10Se50Te40 is calculated by utilizing glass transition temperature (Tg) measured by DSC (Differential Scanning Calorimetry) at different heating rates (β) in the range 5 to 20 K/min. Vogel-Fulcher-Tammann (VFT) equation is fitted to the data of Tg. In addition to the VFT method, three other methods are also used to evaluate m. The fragility index m of the Ge10Se50Te40 system showed the trend of decrease with increasing heating rate but remained stable around 22 for the heating rate 10 K/min. The value of m for the glass is near the lower limit (m ≈ 16) this indicates the alloy is a strong glass forming material in accordance of Angell’s interpretation of fragility. The calculated values of characteristic temperature T0/Tg is very close to 1 which also indicates that clearly the system is most fragile.
Flooding Fragility Experiments and Prediction
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, Curtis L.; Tahhan, Antonio; Muchmore, Cody
2016-09-01
This report describes the work that has been performed on flooding fragility, both the experimental tests being carried out and the probabilistic fragility predictive models being produced in order to use the text results. Flooding experiments involving full-scale doors have commenced in the Portal Evaluation Tank. The goal of these experiments is to develop a full-scale component flooding experiment protocol and to acquire data that can be used to create Bayesian regression models representing the fragility of these components. This work is in support of the Risk-Informed Safety Margin Characterization (RISMC) Pathway external hazards evaluation research and development.
Role for metabotropic glutamate receptor 5 (mGluR5) in the pathogenesis of fragile X syndrome.
Dölen, Gül; Bear, Mark F
2008-03-15
Metabotropic glutamate receptors (mGluRs) have been implicated in a diverse variety of neuronal functions. Studies reviewed here indicate that exaggerated signalling through mGluR5 can account for multiple cognitive and syndromic features of fragile X syndrome, the most common inherited form of mental retardation and autism. Since a reduction of mGluR5 signalling can reverse fragile X phenotypes, these studies provide a compelling rationale for the use of mGluR5 antagonists for the treatment of fragile X and related disorders.
Effects of hyperoxia and caffeine on the expression of fragile site at Xq27.3
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rafi, S.K.; Surana, R.B.; Christopher, K.L.
1996-02-02
To enhance the cytogenetic expression of the fragile X chromosome, we studied the effects of hyperoxia and caffeine on the induction of fragile Xq27.3. A lymphoblastoid cell line (GM 06912) derived from a fragile X male proband was cultured in RPMI 1640 containing 16% dialyzed fetal calf serum. The cells were synchronously subjected to one of 3 different atmospheric oxygen tensions (21%, 21.3 kPa, hyperoxic) during the last 24 hours of the 72 hour culture, immediately after the addition of 2{prime}-deoxy-5-fluorouridine (FUdR) at 25 ng/ml. To study the enhancing effect of caffeine, with or without hyperoxia, a second set ofmore » cultures was additionally subjected to caffeine (2.5 mM) during the last 6 hours of the culture. When the fragility of hyperoxic cells (38.1 kPa dissolved oxygen) was compared to that of normoxic control cells (13.3 kPa dissolved oxygen), the difference was significant (P < 0.05). These data suggest that there is a mean increase in the fragile Xq27.3 expressivity as the dissolved oxygen tension increases. Additionally, we observed that caffeine, with or without hyperoxia, significantly (P <0.05) suppressed the expression of the fragile X site in this lymphoblastoid cell line. 34 refs., 2 tabs.« less
Babies at Double Jeopardy: Medically Fragile Infants and Child Neglect
ERIC Educational Resources Information Center
Fullar, Suzanne A.
2008-01-01
Medically fragile infants, those born prematurely or with other complex medical or genetic problems, are at risk of long-term health and developmental problems. When a medically fragile infant comes home to a family with significant social problems such as domestic violence, mental illness, or substance abuse, the infant is at double jeopardy--at…
Self-Injurious Behavior and Fragile X Syndrome: Findings from the National Fragile X Survey
ERIC Educational Resources Information Center
Symons, Frank J.; Byiers, Breanne J.; Raspa, Melissa; Bishop, Ellen; Bailey, Donald B., Jr.
2010-01-01
We used National Fragile X Survey data in order to examine reported self-injurious behavior (SIB) to (a) generate lifetime and point prevalence estimates, (b) document detailed features of SIB (frequency, types, location, severity) in relation to gender, and (c) compare comorbid conditions between matched pairs (SIB vs. no SIB). Results indicate…
ERIC Educational Resources Information Center
Kover, Sara T.
2012-01-01
Fragile X syndrome is the leading inherited cause of intellectual disability. Most boys with fragile X syndrome have impaired cognition and language deficits, with significant within-syndrome variability. Syntax may be especially delayed relative to nonverbal cognition; however, little is known about the specificity of delay, the sources of that…
The Fragile X Continuum: New Advances and Perspectives
ERIC Educational Resources Information Center
Cornish, K.; Turk, J.; Hagerman, R.
2008-01-01
Fragile X syndrome is the world's most common hereditary cause of intellectual disability in men and to a lesser extent in women. The disorder is caused by the silencing of a single gene on the X chromosome, the Fragile X Mental Retardation Gene-1. A substantial body of research across the disciplines of molecular genetics, child psychiatry and…
Expressive Language during Conversational Speech in Boys with Fragile X Syndrome
ERIC Educational Resources Information Center
Roberts, Joanne E.; Hennon, Elizabeth A.; Price, Johanna R.; Dear, Elizabeth; Anderson, Kathleen; Vandergrift, Nathan A.
2007-01-01
We compared the expressive syntax and vocabulary skills of 35 boys with fragile X syndrome and 27 younger typically developing boys who were at similar nonverbal mental levels. During a conversational speech sample, the boys with fragile X syndrome used shorter, less complex utterances and produced fewer different words than did the typically…
The Trajectory of Mathematics Skills and Working Memory Thresholds in Girls with Fragile X Syndrome
ERIC Educational Resources Information Center
Murphy, Melissa M.; Mazzocco, Michele M. M.
2009-01-01
Fragile X syndrome is a common genetic disorder associated with executive function deficits and poor mathematics achievement. In the present study, we examined changes in math performance during the elementary and middle school years in girls with fragile X syndrome, changes in the working memory loads under which children could complete a…
Adaptive Skills, Behavior Problems, and Parenting Stress in Mothers of Boys with Fragile X Syndrome
ERIC Educational Resources Information Center
Sarimski, Klaus
2010-01-01
The relationship of temperament, atypical behaviors, and adaptive behavior of young boys with Fragile X syndrome on mothers' parenting stress was analyzed. Twenty-six boys with Fragile X syndrome (30-88 months of age) participated. The overall development of the participants was significantly delayed with a specific profile of adaptive behaviors…
ERIC Educational Resources Information Center
Goodrich-Hunsaker, Naomi J.; Wong, Ling M.; McLennan, Yingratana; Srivastava, Siddharth; Tassone, Flora; Harvey, Danielle; Rivera, Susan M.; Simon, Tony J.
2011-01-01
The high frequency of the fragile X premutation in the general population and its emerging neurocognitive implications highlight the need to investigate the effects of the premutation on lifespan cognitive development. Until recently, cognitive function in fragile X premutation carriers (fXPCs) was presumed to be unaffected by the mutation. Here…
ERIC Educational Resources Information Center
Turk, Jeremy; Patton, Michael
2000-01-01
Eighteen boys with fragile X syndrome were compared with 42 with idiopathic intellectual disability, and 45 with Down syndrome. Boys with Down syndrome had more sensory problems and smaller head circumferences than normal. Head circumferences of boys with fragile X syndrome and with idiopathic intellectual disability were larger than normal.…
The Perception of Biological and Mechanical Motion in Female Fragile X Premutation Carriers
ERIC Educational Resources Information Center
Keri, Szabolcs; Benedek, Gyorgy
2010-01-01
Previous studies reported impaired visual information processing in patients with fragile x syndrome and in premutation carriers. In this study, we assessed the perception of biological motion (a walking point-light character) and mechanical motion (a rotating shape) in 25 female fragile x premutation carriers and in 20 healthy non-carrier…
The Fragile X Syndrome: From Molecular Genetics to Neurobiology
ERIC Educational Resources Information Center
Willemsen, Rob; Oostra, Ben A.; Bassell, Gary J.; Dictenberg, Jason
2004-01-01
Since the identification of the FMR1 gene basic research has been focused on the molecular characterization of the FMR1 gene product, the fragile X mental retardation protein (FMRP). Recent developments in fragile X research have provided new insights and knowledge about the physiological function of FMRP in the cell and the nerve cell in…
Behavioral Assessment of Social Anxiety in Females with Turner or Fragile X Syndrome.
ERIC Educational Resources Information Center
Lesniak-Karpiak, Katarzyna; Mazzocco, Michele M. M.; Ross, Judith L.
2003-01-01
This study compared 29 females with Turner syndrome and 21 females with fragile X syndrome (ages 6-22) on a videotaped role-play interaction with 34 females in a comparison group. Three of eight behavioral measures of social skills differentiated the participant groups. Fragile-X subjects required more time to initiate interactions and Turner…
Early White-Matter Abnormalities of the Ventral Frontostriatal Pathway in Fragile X Syndrome
ERIC Educational Resources Information Center
Haas, Brian W.; Barnea-Goraly, Naama; Lightbody, Amy A.; Patnaik, Swetapadma S.; Hoeft, Fumiko; Hazlett, Heather; Piven, Joseph; Reiss, Allan L.
2009-01-01
Aim: Fragile X syndrome is associated with cognitive deficits in inhibitory control and with abnormal neuronal morphology and development. Method: In this study, we used a diffusion tensor imaging (DTI) tractography approach to reconstruct white-matter fibers in the ventral frontostriatal pathway in young males with fragile X syndrome (n = 17;…
Male-Female Characteristics of Fragile X Syndrome.
ERIC Educational Resources Information Center
Caron, Jackie
Fragile X syndrome is the most common cause of mental retardation next to Down syndrome. The syndrome is more prevalent in males because they only have one X chromosome, where the gene for fragile X is carried, while women have two X chromosomes and the normal gene can compensate for the affected chromosome. Certain physical features are…
Fragile X Mental Retardation Protein Regulates Heterosynaptic Plasticity in the Hippocampus
ERIC Educational Resources Information Center
Connor, Steven A.; Hoeffer, Charles A.; Klann, Eric; Nguyen, Peter V.
2011-01-01
Silencing of a single gene, FMR1, is linked to a highly prevalent form of mental retardation, characterized by social and cognitive impairments, known as fragile X syndrome (FXS). The FMR1 gene encodes fragile X mental retardation protein (FMRP), which negatively regulates translation. Knockout of Fmr1 in mice results in enhanced long-term…
Predictors of Stress in Mothers and Fathers of Children with Fragile X Syndrome
ERIC Educational Resources Information Center
McCarthy, Annette; Cuskelly, Monica; van Kraayenoord, Christina E.; Cohen, Jonathan
2006-01-01
This study examined parental and family stress and functioning where there is a child with fragile X syndrome. Mothers and fathers in 40 families were asked about their child with fragile X syndrome, family supports, their psychological stress, the marital relationship, and their family stress. Results indicate parents were well adjusted in terms…
Linguistic and Cognitive Functioning and Autism Symptoms in Young Children with Fragile X Syndrome
ERIC Educational Resources Information Center
Philofsky, Amy; Hepburn, Susan L.; Hayes, Athena; Hagerman, Randi; Rogers, Sally J.
2004-01-01
Linguistic and cognitive profiles were examined in 18 children with autism and 18 children with fragile X syndrome (mean ages = 34 months). State-of-the-art diagnostic procedures for autism symptom identification were administered. Eight children with fragile X met criteria for autism. Comparison of linguistic and cognitive profiles (autism,…
Iron accumulation and dysregulation in the putamen in fragile X-associated tremor/ataxia syndrome.
Ariza, Jeanelle; Rogers, Hailee; Hartvigsen, Anna; Snell, Melissa; Dill, Michael; Judd, Derek; Hagerman, Paul; Martínez-Cerdeño, Verónica
2017-04-01
Fragile X-associated tremor/ataxia syndrome is an adult-onset disorder associated with premutation alleles of the FMR1 gene. This disorder is characterized by progressive action tremor, gait ataxia, and cognitive decline. Fragile X-associated tremor/ataxia syndrome pathology includes dystrophic white matter and intranuclear inclusions in neurons and astrocytes. We previously demonstrated that the transport of iron into the brain is altered in fragile X-associated tremor/ataxia syndrome; therefore, we also expect an alteration of iron metabolism in brain areas related to motor control. Iron is essential for cell metabolism, but uncomplexed iron leads to oxidative stress and contributes to the development of neurodegenerative diseases. We investigated a potential iron modification in the putamen - a structure that participates in motor learning and performance - in fragile X-associated tremor/ataxia syndrome. We used samples of putamen obtained from 9 fragile X-associated tremor/ataxia syndrome and 9 control cases to study iron localization using Perl's method, and iron-binding proteins using immunostaining. We found increased iron deposition in neuronal and glial cells in the putamen in fragile X-associated tremor/ataxia syndrome. We also found a generalized decrease in the amount of the iron-binding proteins transferrin and ceruloplasmin, and decreased number of neurons and glial cells that contained ceruloplasmin. However, we found increased levels of iron, transferrin, and ceruloplasmin in microglial cells, indicating an attempt by the immune system to remove the excess iron. Overall, found a deficit in proteins that eliminate extra iron from the cells with a concomitant increase in the deposit of cellular iron in the putamen in Fragile X-associated tremor/ataxia syndrome. © 2017 International Parkinson and Movement Disorder Society. © 2017 International Parkinson and Movement Disorder Society.
Isolation of the human chromosomal band Xq28 within somatic cell hybrids by fragile X site breakage.
Warren, S T; Knight, S J; Peters, J F; Stayton, C L; Consalez, G G; Zhang, F P
1990-01-01
The chromosomal fragile-site mapping to Xq27.3 is associated with a frequent form of mental retardation and is prone to breakage after induced deoxyribonucleotide pool perturbation. The human hypoxanthine phosphoribosyltransferase (HPRT) and glucose-6-phosphate dehydrogenase (G6PD) genes flank the fragile X chromosome site and can be used to monitor integrity of the site in human-hamster somatic cell hybrids deficient in the rodent forms of these activities. After induction of the fragile X site, negative selection for HPRT and positive enrichment for G6PD resulted in 31 independent colonies of HPRT-,G6PD+ phenotype. Southern blot analysis demonstrated the loss of all tested markers proximal to the fragile X site with retention of all tested human Xq28 loci in a majority of the hybrids. In situ hybridization with a human-specific probe demonstrated the translocation of a small amount of human DNA to rodent chromosomes in these hybrids, suggesting chromosome breakage at the fragile X site and the subsequent translocation of Xq28. Southern blot hybridization of hybrid-cell DNA, resolved by pulsed-field gel electrophoresis, for human-specific repetitive sequences revealed abundant CpG-islands within Xq28, consistent with its known gene density. The electrophoretic banding patterns of human DNA among the hybrids were remarkably consistent, suggesting that fragile X site breakage is limited to a relatively small region in Xq27-28. These somatic cell hybrids, containing Xq27.3-qter as the sole human DNA, will aid the search for DNA associated with the fragile X site and will augment the high resolution genomic analysis of Xq28, including the identification of candidate genes for genetic-disease loci mapping to this region. Images PMID:2339126
Age-dependent cognitive impairment in a Drosophila fragile X model and its pharmacological rescue.
Choi, Catherine H; McBride, Sean M J; Schoenfeld, Brian P; Liebelt, David A; Ferreiro, David; Ferrick, Neal J; Hinchey, Paul; Kollaros, Maria; Rudominer, Rebecca L; Terlizzi, Allison M; Koenigsberg, Eric; Wang, Yan; Sumida, Ai; Nguyen, Hanh T; Bell, Aaron J; McDonald, Thomas V; Jongens, Thomas A
2010-06-01
Fragile X syndrome afflicts 1 in 2,500 individuals and is the leading heritable cause of mental retardation worldwide. The overriding clinical manifestation of this disease is mild to severe cognitive impairment. Age-dependent cognitive decline has been identified in Fragile X patients, although it has not been fully characterized nor examined in animal models. A Drosophila model of this disease has been shown to display phenotypes bearing similarity to Fragile X symptoms. Most notably, we previously identified naive courtship and memory deficits in young adults with this model that appear to be due to enhanced metabotropic glutamate receptor (mGluR) signaling. Herein we have examined age-related cognitive decline in the Drosophila Fragile X model and found an age-dependent loss of learning during training. We demonstrate that treatment with mGluR antagonists or lithium can prevent this age-dependent cognitive impairment. We also show that treatment with mGluR antagonists or lithium during development alone displays differential efficacy in its ability to rescue naive courtship, learning during training and memory in aged flies. Furthermore, we show that continuous treatment during aging effectively rescues all of these phenotypes. These results indicate that the Drosophila model recapitulates the age-dependent cognitive decline observed in humans. This places Fragile X in a category with several other diseases that result in age-dependent cognitive decline. This demonstrates a role for the Drosophila Fragile X Mental Retardation Protein (dFMR1) in neuronal physiology with regard to cognition during the aging process. Our results indicate that misregulation of mGluR activity may be causative of this age onset decline and strengthens the possibility that mGluR antagonists and lithium may be potential pharmacologic compounds for counteracting several Fragile X symptoms.
Epilepsy in fragile-X-syndrome mimicking panayiotopoulos syndrome: Description of three patients.
Bonanni, Paolo; Casellato, Susanna; Fabbro, Franco; Negrin, Susanna
2017-10-01
Fragile-X-syndrome is the most common cause of inherited intellectual disability. Epilepsy is reported to occur in 10-20% of individuals with Fragile-X-syndrome. A frequent seizure/electroencephalogram (EEG) pattern resembles that of benign rolandic epilepsy. We describe the clinical features, EEG findings and evolution in three patients affected by Fragile-X-syndrome and epilepsy mimicking Panayiotopoulos syndrome. Age at seizure onset was between 4 and about 7 years. Seizures pattern comprised a constellation of autonomic symptoms with unilateral deviation of the eyes and ictal syncope. Duration of the seizures could be brief or lengthy. Interictal EEGs revealed functional multifocal abnormalities. The evolution was benign in all patients with seizures remission before the age of 14. This observation expands the spectrum of benign epileptic phenotypes present in Fragile-X-syndrome and may be quite helpful in guiding anticonvulsant management and counseling families as to expectations regarding seizure remission. © 2017 Wiley Periodicals, Inc.
Foote, Molly M; Careaga, Milo; Berman, Robert F
2016-08-01
To describe in this review how research using mouse models developed to study the Fragile X premutation (PM) and Fragile X-associated tremor/ataxia syndrome (FXTAS) have contributed to understanding these disorders. PM carriers bear an expanded CGG trinucleotide repeat on the Fragile X Mental Retardation 1 (FMR1) gene, and are at risk for developing the late onset neurodegenerative disorder FXTAS. Much has been learned about these genetic disorders from the development and study of mouse models. This includes new insights into the early cellular and molecular events that occur in PM carriers and in FXTAS, the presence of multiorgan pathology beyond the CNS, immunological dysregulation, unexpected synthesis of a potentially toxic peptide in FXTAS (i.e., FMRpolyG), and evidence that the disease process may be halted or reversed by appropriate molecular therapies given early in the course of disease.
Uniform Laser Excitation And Detection In Capillary Array Electrophoresis System And Method.
Li, Qingbo; Zhou, Songsan; Liu, Changsheng
2003-10-07
A capillary electrophoresis system comprises capillaries positioned in parallel to each other forming a plane. The capillaries are configured to allow samples to migrate. A light source is configured to illuminate the capillaries and the samples therein. This causes the samples to emit light. A lens is configured to receive the light emitted by the samples and positioned directly over a first group of the capillaries and obliquely over a second group of the capillaries. The light source is further configured to illuminate the second group of capillaries more than the first group of the capillaries such that amount of light received by the lens from the first group of capillaries is substantially identical to amount of light received from the second group of capillaries when an identical amount of the samples is migrating through the first and second group capillaries.
Cellular Basis for Learning Impairment in Fragile X Syndrome
2015-08-01
the leading cause of inherited intellectual disability and results in cognitive impairment, hyperactivity , attention deficits , seizure disorders ...impairment, hyperactivity , attention deficits and seizure disorders . Previous studies using a mouse model for FXS (Fmr1- KO) have described impairments in...neurogenesis in adult fragile X mice, test fragile X mice for learning deficits in hippocampal-independent tasks, and determine how synaptic
Brief Report: Autism of the Asperger Type Associated with an Autosomal Fragile Site.
ERIC Educational Resources Information Center
Saliba, Joseph R.; Griffiths, Mike
1990-01-01
This case study describes a 12-year-old boy with autism in association with the folate-sensitive fragile site fra(2)(q13). Cytogenetic results of blood analysis are described, and two possibilities are discussed: the fragile site may be a coincidental finding unrelated to the autism, or may represent an area of potential gene damage. (JDD)
ERIC Educational Resources Information Center
Cornish, Kim; Cole, Victoria; Longhi, Elena; Karmiloff-Smith, Annette; Scerif, Gaia
2012-01-01
Basic attentional processes and their impact on developmental trajectories in fragile X syndrome were assessed in a 3-year prospective study. Although fragile X syndrome is a monogenic X-linked disorder, there is striking variability in outcomes even in young boys with the condition. Attention is a key factor constraining interactions with the…
Discourse Skills of Boys with Fragile X Syndrome in Comparison to Boys with Down Syndrome
ERIC Educational Resources Information Center
Roberts, Joanne; Martin, Gary E.; Moskowitz, Lauren; Harris, Adrianne A.; Foreman, Jamila; Nelson, Lauren
2007-01-01
Purpose: This study compared the conversational discourse skills of boys who have fragile X syndrome with and without autism spectrum disorder (ASD) with those of boys with Down syndrome and boys who are typically developing. Method: Participants were boys who have fragile X syndrome with (n = 26) and without (n = 28) ASD, boys with Down syndrome…
ERIC Educational Resources Information Center
Patton, Lori D.; Jordan, Jodi L.
2017-01-01
This case centers on a Black woman school administrator and efforts to disrupt Whiteness among an urban elementary school teaching staff. The case details the resistance she encounters while encouraging teachers to confront "White fragility" and consider how their fragile perspectives on race and racism shape how they educate Black…
ERIC Educational Resources Information Center
Lewis, P.; Abbeduto, L.; Murphy, M.; Richmond, E.; Giles, N.; Bruno, L.; Schroeder, S.; Anderson, J.; Orsmond, G.
2006-01-01
Background: Research on parental well-being has focused largely on Down syndrome and autism; however, fragile X syndrome is likely to pose different challenges for parents compared with these other diagnostic conditions. Moreover, there is considerable variability among youth with fragile X syndrome; for example, 25% to 33% of affected youth meet…
ERIC Educational Resources Information Center
Kover, Sara T.; McDuffie, Andrea; Abbeduto, Leonard; Brown, W. Ted
2012-01-01
Purpose: In this study, the authors examined the impact of sampling context on multiple aspects of expressive language in male participants with fragile X syndrome in comparison to male participants with Down syndrome or typical development. Method: Participants with fragile X syndrome (n = 27), ages 10-17 years, were matched groupwise on…
ERIC Educational Resources Information Center
Martin, Gary E.; Roberts, Joanne E.; Helm-Estabrooks, Nancy; Sideris, John; Vanderbilt, Jacqueline; Moskowitz, Lauren
2012-01-01
Verbal perseveration is a frequently reported language characteristic of males with Fragile X syndrome and may be a defining feature or hallmark of the syndrome. We compared the verbal perseveration of boys with Fragile X syndrome with (n = 29) and without (n = 30) autism spectrum disorder, boys with Down syndrome (n = 27), and typically…
Role of microRNA Pathway in Mental Retardation
Qurashi, Abrar; Chang, Shuang; Jin, Peng
2007-01-01
Deficits in cognitive functions lead to mental retardation (MR). Understanding the genetic basis of inherited MR has provided insights into the pathogenesis of MR. Fragile X syndrome is one of the most common forms of inherited MR, caused by the loss of functional Fragile X Mental Retardation Protein (FMRP). MicroRNAs (miRNAs) are endogenous, single-stranded RNAs between 18 and 25 nucleotides in length, which have been implicated in diversified biological pathways. Recent studies have linked the miRNA pathway to fragile X syndrome. Here we review the role of the miRNA pathway in fragile X syndrome and discuss its implication in MR in general. PMID:17982588
Interferon-γ Drives Treg Fragility to Promote Anti-tumor Immunity.
Overacre-Delgoffe, Abigail E; Chikina, Maria; Dadey, Rebekah E; Yano, Hiroshi; Brunazzi, Erin A; Shayan, Gulidanna; Horne, William; Moskovitz, Jessica M; Kolls, Jay K; Sander, Cindy; Shuai, Yongli; Normolle, Daniel P; Kirkwood, John M; Ferris, Robert L; Delgoffe, Greg M; Bruno, Tullia C; Workman, Creg J; Vignali, Dario A A
2017-06-01
Regulatory T cells (T regs ) are a barrier to anti-tumor immunity. Neuropilin-1 (Nrp1) is required to maintain intratumoral T reg stability and function but is dispensable for peripheral immune tolerance. T reg -restricted Nrp1 deletion results in profound tumor resistance due to T reg functional fragility. Thus, identifying the basis for Nrp1 dependency and the key drivers of T reg fragility could help to improve immunotherapy for human cancer. We show that a high percentage of intratumoral NRP1 + T regs correlates with poor prognosis in melanoma and head and neck squamous cell carcinoma. Using a mouse model of melanoma where Nrp1-deficient (Nrp1 -/- ) and wild-type (Nrp1 +/+ ) T regs can be assessed in a competitive environment, we find that a high proportion of intratumoral Nrp1 -/- T regs produce interferon-γ (IFNγ), which drives the fragility of surrounding wild-type T regs , boosts anti-tumor immunity, and facilitates tumor clearance. We also show that IFNγ-induced T reg fragility is required for response to anti-PD1, suggesting that cancer therapies promoting T reg fragility may be efficacious. Copyright © 2017 Elsevier Inc. All rights reserved.
Jacobs, S; Cheng, C; Doering, L C
2016-06-02
Astrocytes are now recognized as key players in the neurobiology of neurodevelopmental disorders such as Fragile X syndrome. However, the nature of Fragile X astrocyte-mediated control of dendrite development in subtypes of hippocampal neurons is not yet known. We used a co-culture procedure in which wildtype primary hippocampal neurons were cultured with astrocytes from either a wildtype or Fragile X mouse, for either 7, 14 or 21 days. The neurons were processed for immunocytochemistry with the dendritic marker MAP2, classified by morphological criteria into one of five neuronal subtypes, and subjected to Sholl analyses. Both linear and semi-log methods of Sholl analyses were applied to the neurons in order to provide an in depth analysis of the dendritic arborizations. We found that Fragile X astrocytes affect the development of dendritic arborization of all subtypes of wildtype hippocampal neurons. Furthermore, we show that hippocampal neurons with spiny stellate neuron morphology exhibit the most pervasive developmental delays, with significant dendritic arbor alterations persisting at 21 days in culture. The results further dictate the critical role astrocytes play in governing neuronal morphology including altered dendrite development in Fragile X. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.
Chromosome fragility at FRAXA in human cleavage stage embryos at risk for fragile X syndrome.
Verdyck, Pieter; Berckmoes, Veerle; De Vos, Anick; Verpoest, Willem; Liebaers, Inge; Bonduelle, Maryse; De Rycke, Martine
2015-10-01
Fragile X syndrome (FXS), the most common inherited intellectual disability syndrome, is caused by expansion and hypermethylation of the CGG repeat in the 5' UTR of the FMR1 gene. This expanded repeat, also known as the rare fragile site FRAXA, causes X chromosome fragility in cultured cells from patients but only when induced by perturbing pyrimidine synthesis. We performed preimplantation genetic diagnosis (PGD) on 595 blastomeres biopsied from 442 cleavage stage embryos at risk for FXS using short tandem repeat (STR) markers. In six blastomeres, from five embryos an incomplete haplotype was observed with loss of all alleles telomeric to the CGG repeat. In all five embryos, the incomplete haplotype corresponded to the haplotype carrying the CGG repeat expansion. Subsequent analysis of additional blastomeres from three embryos by array comparative genomic hybridization (aCGH) confirmed the presence of a terminal deletion with a breakpoint close to the CGG repeat in two blastomeres from one embryo. A blastomere from another embryo showed the complementary duplication. We conclude that a CGG repeat expansion at FRAXA causes X chromosome fragility in early human IVF embryos at risk for FXS. © 2015 Wiley Periodicals, Inc.
The developmental switch in GABA polarity is delayed in fragile X mice.
He, Qionger; Nomura, Toshihiro; Xu, Jian; Contractor, Anis
2014-01-08
Delays in synaptic and neuronal development in the cortex are key hallmarks of fragile X syndrome, a prevalent neurodevelopmental disorder that causes intellectual disability and sensory deficits and is the most common known cause of autism. Previous studies have demonstrated that the normal progression of plasticity and synaptic refinement during the critical period is altered in the cortex of fragile X mice. Although the disruptions in excitatory synapses are well documented in fragile X, there is less known about inhibitory neurotransmission during the critical period. GABAergic transmission plays a crucial trophic role in cortical development through its early depolarizing action. At the end of cortical critical period, response properties of GABA transform into their mature hyperpolarizing type due to developmental changes in intracellular chloride homeostasis. We found that the timing of the switch from depolarizing to hyperpolarizing GABA is delayed in the cortex of fragile X mice and there is a concurrent alteration in the expression of the neuronal chloride cotransporter NKCC1 that promotes the accumulation of intracellular chloride. Disruption of the trophic effects of GABA during cortical development could contribute to the altered trajectory of synaptic maturation in fragile X syndrome.
Gupta, M J; Shah, S; Peterson, S; Baim, S
2018-06-04
In spite of being a public health problem of pandemic proportions, osteoporosis continues to be underdiagnosed and undertreated especially in older adults with fragility fractures. Confirmation of this hypothesis resulted in the development of a novel Fracture Liaison Service (Rush FLS). Results of the first 12 months of operation revealed that patients with confirmed fragility fracture do not have a timely diagnosis at fracture occurrence or treatment of their disease. The Rush FLS is an effective fracture liaison model. Determining the prevalence of undiagnosed and untreated osteoporosis in fragility fracture patients, either admitted to an academic tertiary care center or treated and discharged from the center's emergency department to be followed in the endocrinology bone clinic, using an innovative, educational, low-cost, physician-run Fracture Liaison Service (FLS). An automated alert was integrated into the electronic medical record at Rush University Medical Center (RUMC), triggered by historical and/or acute fracture(s) in patients 50 years or older, in patients that were either admitted to the hospital or in patients evaluated in the emergency department and discharged to be followed in the endocrinology bone clinic. We report the results of the first 12 months of operation in patients admitted to the hospital. First acute fragility fracture(s) were identified in 36% (80/223), only historical fragility fracture(s) in 28% (63/223) and both acute and historical fragility fracture(s) in 36% (80/223). The cumulative subgroup with historical fragility fractures with/without new fractures included 67% (96/143) without a previous diagnosis of osteoporosis. First acute fragility fracture group included 83.8% (67/80) without a previous diagnosis of osteoporosis. Rush FLS "captured missed opportunities" in 73.1% (163/223) of previously undiagnosed and 77.1% (172/223) of previously untreated osteoporosis patients. Dual-energy x-ray absorptiometry (DXA) prior to FLS consult was confirmed in 30% (67/223). Vitamin D deficiency (25-hydroxy vitamin D < 20 ng/ml) in 41.9% (78/186) including undetectable levels in 16.6% (31/186) and secondary hyperparathyroidism in 43.3% (78/180) were the most common laboratory confirmed secondary etiologies for bone loss. This study reported undiagnosed, uninvestigated, and untreated osteoporosis in the majority of fragility fracture patients seen by the Rush FLS in the first 12 months of operation.
Capillary electrophoresis electrospray ionization mass spectrometry interface
Smith, Richard D.; Severs, Joanne C.
1999-01-01
The present invention is an interface between a capillary electrophoresis separation capillary end and an electrospray ionization mass spectrometry emitter capillary end, for transporting an anolyte sample from a capillary electrophoresis separation capillary to a electrospray ionization mass spectrometry emitter capillary. The interface of the present invention has: (a) a charge transfer fitting enclosing both of the capillary electrophoresis capillary end and the electrospray ionization mass spectrometry emitter capillary end; (b) a reservoir containing an electrolyte surrounding the charge transfer fitting; and (c) an electrode immersed into the electrolyte, the electrode closing a capillary electrophoresis circuit and providing charge transfer across the charge transfer fitting while avoiding substantial bulk fluid transfer across the charge transfer fitting. Advantages of the present invention have been demonstrated as effective in providing high sensitivity and efficient analyses.
Tirilazad mesylate protects stored erythrocytes against osmotic fragility.
Epps, D E; Knechtel, T J; Bacznskyj, O; Decker, D; Guido, D M; Buxser, S E; Mathews, W R; Buffenbarger, S L; Lutzke, B S; McCall, J M
1994-12-01
The hypoosmotic lysis curve of freshly collected human erythrocytes is consistent with a single Gaussian error function with a mean of 46.5 +/- 0.25 mM NaCl and a standard deviation of 5.0 +/- 0.4 mM NaCl. After extended storage of RBCs under standard blood bank conditions the lysis curve conforms to the sum of two error functions instead of a possible shift in the mean and a broadening of a single error function. Thus, two distinct sub-populations with different fragilities are present instead of a single, broadly distributed population. One population is identical to the freshly collected erythrocytes, whereas the other population consists of osmotically fragile cells. The rate of generation of the new, osmotically fragile, population of cells was used to probe the hypothesis that lipid peroxidation is responsible for the induction of membrane fragility. If it is so, then the antioxidant, tirilazad mesylate (U-74,006f), should protect against this degradation of stored erythrocytes. We found that tirilazad mesylate, at 17 microM (1.5 mol% with respect to membrane lecithin), retards significantly the formation of the osmotically fragile RBCs. Concomitantly, the concentration of free hemoglobin which accumulates during storage is markedly reduced by the drug. Since the presence of the drug also decreases the amount of F2-isoprostanes formed during the storage period, an antioxidant mechanism must be operative. These results demonstrate that tirilazad mesylate significantly decreases the number of fragile erythrocytes formed during storage in the blood bank.
Lozano, Reymundo; Rosero, Carolina Alba; Hagerman, Randi J
2014-11-01
The fragile X mental retardation 1 gene (FMR1), which codes for the fragile X mental retardation 1 protein (FMRP), is located at Xp27.3. The normal allele of the FMR1 gene typically has 5 to 40 CGG repeats in the 5' untranslated region; abnormal alleles of dynamic mutations include the full mutation (> 200 CGG repeats), premutation (55-200 CGG repeats) and the gray zone mutation (45-54 CGG repeats). Premutation carriers are common in the general population with approximately 1 in 130-250 females and 1 in 250-810 males, whereas the full mutation and Fragile X syndrome (FXS) occur in approximately 1 in 4000 to 1 in 7000. FMR1 mutations account for a variety of phenotypes including the most common monogenetic cause of inherited intellectual disability (ID) and autism (FXS), the most common genetic form of ovarian failure, the fragile X-associated primary ovarian insufficiency (FXPOI, premutation); and fragile X-associated tremor/ataxia syndrome (FXTAS, premutation). The premutation can also cause developmental problems including ASD and ADHD especially in boys and psychopathology including anxiety and depression in children and adults. Some premutation carriers can have a deficit of FMRP and some unmethylated full mutation individuals can have elevated FMR1 mRNA that is considered a premutation problem. Therefore the term "Fragile X Spectrum Disorder" (FXSD) should be used to include the wide range of overlapping phenotypes observed in affected individuals with FMR1 mutations. In this review we focus on the phenotypes and genotypes of children with FXSD.
Bourgeois, James A
2016-08-01
Clinical neuropsychologists benefit from clinical currency in recently ascertained neuropsychiatric illness, such as fragile X premutation (FXPM) disorders. The author reviewed the clinical literature through 2016 for neuropsychiatric phenotypes in FXPM disorders, including patients with fragile X-associated tremor/ataxia syndrome (FXTAS). A PubMed search using the search terms 'Fragile X,' 'Premutation,' 'Carriers,' 'Psychiatric,' 'Dementia,' 'Mood,' and 'Anxiety' for citations in the clinical literature through 2016 was reviewed for studies specifically examining the neuropsychiatric phenotype in FXPM patients. The relevant articles were classified according to specific neuropsychiatric syndromes, including child onset, adult onset with and without FXTAS, as well as common systemic comorbidities in FXPM patients. Eighty-six articles were reviewed for the neuropsychiatric and other phenotypes in FXPM patients. The neuropsychiatric phenotype in FXPM patients is distinct from that of full mutation (Fragile X Syndrome) patients. FXTAS is associated with a specific cortical-subcortical major or mild neurocognitive disorder (NCD). FXPM patients are at risk for neuropsychiatric illness. In addition, FXPM patients are at risk for other systemic conditions that should raise suspicion for FXPM-associated illnesses. Clinicians should consider a diagnosis of FXPM-associated neuropsychiatric illness when patients with specific clinical scenarios are encountered; especially in patient pedigrees consistent with a typical (often multigenerational) presentation of fragile X-associated conditions, confirmatory genetic testing should be considered. Clinical management should take into account the psychological challenges of a multigenerational genetic neuropsychiatric illness with a variable CNS and systemic clinical phenotype.
NASA Astrophysics Data System (ADS)
Tournier, Robert F.
2014-12-01
An undercooled liquid is unstable. The driving force of the glass transition at Tg is a change of the undercooled-liquid Gibbs free energy. The classical Gibbs free energy change for a crystal formation is completed including an enthalpy saving. The crystal growth critical nucleus is used as a probe to observe the Laplace pressure change Δp accompanying the enthalpy change -Vm×Δp at Tg where Vm is the molar volume. A stable glass-liquid transition model predicts the specific heat jump of fragile liquids at T≤Tg, the Kauzmann temperature TK where the liquid entropy excess with regard to crystal goes to zero, the equilibrium enthalpy between TK and Tg, the maximum nucleation rate at TK of superclusters containing magic atom numbers, and the equilibrium latent heats at Tg and TK. Strong-to-fragile and strong-to-strong liquid transitions at Tg are also described and all their thermodynamic parameters are determined from their specific heat jumps. The existence of fragile liquids quenched in the amorphous state, which do not undergo liquid-liquid transition during heating preceding their crystallization, is predicted. Long ageing times leading to the formation at TK of a stable glass composed of superclusters containing up to 147 atom, touching and interpenetrating, are evaluated from nucleation rates. A fragile-to-fragile liquid transition occurs at Tg without stable-glass formation while a strong glass is stable after transition.
Global Identification of Disease-Associated Genes in Fragile X Cells
2017-03-01
identify those specific gene substrates of FMRP, particularly those expressed in the brain , that are implicated in FXS progression. Moreover, we use...the co-localized R-loop formation and chromosome fragility in Fragile X cells, particularly at the brain -expressed genes, by ChIP-seq (detecting...X mental retardation protein February 2016, NGS Data Analysis & Informatics Conference, San Diego, California (Poster presentation) Title: Global
ERIC Educational Resources Information Center
Mazzocco, Michele M. M.
2001-01-01
This study examined whether indicators of math learning disability were observed in 35 5- and 6-year-olds with either neurofibromatosis, Turner Syndrome, or fragile X syndrome and compared to controls. Findings indicate that girls with fragile X or Turner syndrome but not neurofibromatosis are significantly more likely to have specific math…
ERIC Educational Resources Information Center
Murphy, Melissa M.; Mazzocco, Michele M. M.
2008-01-01
The present study focuses on math and related skills among 32 girls with fragile X (n = 14) or Turner (n = 18) syndrome during late elementary school. Performance in each syndrome group was assessed relative to Full Scale IQ-matched comparison groups of girls from the general population (n = 32 and n = 89 for fragile X syndrome and Turner…
ERIC Educational Resources Information Center
Moss, Joanna; Oliver, Chris; Nelson, Lisa; Richards, Caroline; Hall, Scott
2013-01-01
An atypical presentation of autism spectrum disorder is noted in Cornelia de Lange and Fragile X syndromes, but there are few detailed empirical descriptions. Participants in this study were individuals with Cornelia de Lange syndrome (n = 130, M age = 17.19), Fragile X syndrome (n = 182, M age = 16.94), and autism spectrum disorder (n = 142, M…
ERIC Educational Resources Information Center
Brazendale, Allison; Adlof, Suzanne; Klusek, Jessica; Roberts, Jane
2015-01-01
Clinical Question: Would a child with fragile X syndrome benefit more from phonemic awareness and phonics instruction or whole-word training to increase reading skills? Method: Systematic review. Study Sources: PsycINFO. Search Terms: fragile X OR Down syndrome OR cognitive impairment OR cognitive deficit OR cognitive disability OR intellectual…
NASA Astrophysics Data System (ADS)
Gangopadhyay, A. K.; Pueblo, C. E.; Dai, R.; Johnson, M. L.; Ashcraft, R.; Van Hoesen, D.; Sellers, M.; Kelton, K. F.
2017-04-01
The thermal expansion coefficients, structure factors, and viscosities of twenty-five equilibrium and supercooled metallic liquids have been measured using an electrostatic levitation (ESL) facility. The structure factor was measured at the Advanced Photon Source, Argonne, using the ESL. A clear connection between liquid fragility and structural and volumetric changes at high temperatures is established; the observed changes are larger for the more fragile liquids. It is also demonstrated that the fragility of metallic liquids is determined to a large extent by the cohesive energy and is, therefore, predictable. These results are expected to provide useful guidance in the future design of metallic glasses.
Fragility and glass transition for binary mixtures of 1,2-propanediol and LiBF4
NASA Astrophysics Data System (ADS)
Terashima, Y.; Mori, M.; Sugimoto, N.; Takeda, K.
2014-04-01
The fragility and glass transition for binary mixtures of 1,2-propanediol and LiBF4 were investigated by measuring the heating rate dependence of glass transition temperature (Tg) using differential scanning calorimetry. With increasing LiBF4 mole fraction, x, up to 0.25, fragility, m, increased rapidly from 53 to 85, and then remained approximately unchanged for x > 0.25. The concentration dependences of Tg and heat capacity jump at Tg also showed anomalies around x = 0.25. We suggest this mixture transformed from a moderate to quite fragile liquid at x = 0.25 because of a structural change from a hydrogen-bonding- to ionic-interaction-dominant system.
DNA Secondary Structure at Chromosomal Fragile Sites in Human Disease
Thys, Ryan G; Lehman, Christine E; Pierce, Levi C. T; Wang, Yuh-Hwa
2015-01-01
DNA has the ability to form a variety of secondary structures that can interfere with normal cellular processes, and many of these structures have been associated with neurological diseases and cancer. Secondary structure-forming sequences are often found at chromosomal fragile sites, which are hotspots for sister chromatid exchange, chromosomal translocations, and deletions. Structures formed at fragile sites can lead to instability by disrupting normal cellular processes such as DNA replication and transcription. The instability caused by disruption of replication and transcription can lead to DNA breakage, resulting in gene rearrangements and deletions that cause disease. In this review, we discuss the role of DNA secondary structure at fragile sites in human disease. PMID:25937814
Nesina, I P; Polishchuk, L Z; Oliĭnichenko, P I
2000-01-01
Results of comparative study of spontaneous and 5-bromdeoxyuridine-induced fragility of peripheral blood lymphocytes chromosomes in 9 patients with colorectal adenocarcinoma were presented. It was shown the increase of average spontaneous level of chromosomal fragility in patients with tumor aggregation in family as well as without it to 4.5 +/- 1.0 and 5.3 +/- 1.1 per 100 tested cells, accordingly. The increase of average level of damaged chromosomes in spectrum of rare sites to 12.5 +/- 2.6 in the patients with tumor aggregation in pedigree comparing to the patients without oncopathology in family 8.0 +/- 1.7 was observed. The most number of rare fragile sites was observed in 1q21 site of the chromosome 1. Possible connection between fragile sites of chromosomes in normal cells and malignant processes in the patients with colorectal cancer is discussed.
Local variation of fragility and glass transition temperature of ultra-thin supported polymer films.
Hanakata, Paul Z; Douglas, Jack F; Starr, Francis W
2012-12-28
Despite extensive efforts, a definitive picture of the glass transition of ultra-thin polymer films has yet to emerge. The effect of film thickness h on the glass transition temperature T(g) has been widely examined, but this characterization does not account for the fragility of glass-formation, which quantifies how rapidly relaxation times vary with temperature T. Accordingly, we simulate supported polymer films of a bead-spring model and determine both T(g) and fragility, both as a function of h and film depth. We contrast changes in the relaxation dynamics with density ρ and demonstrate the limitations of the commonly invoked free-volume layer model. As opposed to bulk polymer materials, we find that the fragility and T(g) do not generally vary proportionately. Consequently, the determination of the fragility profile--both locally and for the film as a whole--is essential for the characterization of changes in film dynamics with confinement.
Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS) Motor Dysfunction Modeled in Mice.
Foote, Molly; Arque, Gloria; Berman, Robert F; Santos, Mónica
2016-10-01
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder that affects some carriers of the fragile X premutation (PM). In PM carriers, there is a moderate expansion of a CGG trinucleotide sequence (55-200 repeats) in the fragile X gene (FMR1) leading to increased FMR1 mRNA and small to moderate decreases in the fragile X mental retardation protein (FMRP) expression. The key symptoms of FXTAS include cerebellar gait ataxia, kinetic tremor, sensorimotor deficits, neuropsychiatric changes, and dementia. While the specific trigger(s) that causes PM carriers to progress to FXTAS pathogenesis remains elusive, the use of animal models has shed light on the underlying neurobiology of the altered pathways involved in disease development. In this review, we examine the current use of mouse models to study PM and FXTAS, focusing on recent advances in the field. Specifically, we will discuss the construct, face, and predictive validities of these PM mouse models, the insights into the underlying disease mechanisms, and potential treatments.
Developing ShakeCast statistical fragility analysis framework for rapid post-earthquake assessment
Lin, K.-W.; Wald, D.J.
2012-01-01
When an earthquake occurs, the U. S. Geological Survey (USGS) ShakeMap estimates the extent of potentially damaging shaking and provides overall information regarding the affected areas. The USGS ShakeCast system is a freely-available, post-earthquake situational awareness application that automatically retrieves earthquake shaking data from ShakeMap, compares intensity measures against users’ facilities, sends notifications of potential damage to responsible parties, and generates facility damage assessment maps and other web-based products for emergency managers and responders. We describe notable improvements of the ShakeMap and the ShakeCast applications. We present a design for comprehensive fragility implementation, integrating spatially-varying ground-motion uncertainties into fragility curves for ShakeCast operations. For each facility, an overall inspection priority (or damage assessment) is assigned on the basis of combined component-based fragility curves using pre-defined logic. While regular ShakeCast users receive overall inspection priority designations for each facility, engineers can access the full fragility analyses for further evaluation.
Laser illumination of multiple capillaries that form a waveguide
Dhadwal, Harbans S.; Quesada, Mark A.; Studier, F. William
1998-08-04
A system and method are disclosed for efficient laser illumination of the interiors of multiple capillaries simultaneously, and collection of light emitted from them. Capillaries in a parallel array can form an optical waveguide wherein refraction at the cylindrical surfaces confines side-on illuminating light to the core of each successive capillary in the array. Methods are provided for determining conditions where capillaries will form a waveguide and for assessing and minimizing losses due to reflection. Light can be delivered to the arrayed capillaries through an integrated fiber optic transmitter or through a pair of such transmitters aligned coaxially at opposite sides of the array. Light emitted from materials within the capillaries can be carried to a detection system through optical fibers, each of which collects light from a single capillary, with little cross talk between the capillaries. The collection ends of the optical fibers can be in a parallel array with the same spacing as the capillary array, so that the collection fibers can all be aligned to the capillaries simultaneously. Applicability includes improving the efficiency of many analytical methods that use capillaries, including particularly high-throughput DNA sequencing and diagnostic methods based on capillary electrophoresis.
Laser illumination of multiple capillaries that form a waveguide
Dhadwal, H.S.; Quesada, M.A.; Studier, F.W.
1998-08-04
A system and method are disclosed for efficient laser illumination of the interiors of multiple capillaries simultaneously, and collection of light emitted from them. Capillaries in a parallel array can form an optical waveguide wherein refraction at the cylindrical surfaces confines side-on illuminating light to the core of each successive capillary in the array. Methods are provided for determining conditions where capillaries will form a waveguide and for assessing and minimizing losses due to reflection. Light can be delivered to the arrayed capillaries through an integrated fiber optic transmitter or through a pair of such transmitters aligned coaxially at opposite sides of the array. Light emitted from materials within the capillaries can be carried to a detection system through optical fibers, each of which collects light from a single capillary, with little cross talk between the capillaries. The collection ends of the optical fibers can be in a parallel array with the same spacing as the capillary array, so that the collection fibers can all be aligned to the capillaries simultaneously. Applicability includes improving the efficiency of many analytical methods that use capillaries, including particularly high-throughput DNA sequencing and diagnostic methods based on capillary electrophoresis. 35 figs.
Rangelia vitalii in a free-ranging maned wolf (Chrysocyon brachyurus) and co-infections.
Silveira, Julia Angélica Gonçalves; D'Elia, Mirella Lauria; de Oliveira Avelar, Isabela; de Almeida, Lara Ribeiro; Dos Santos, Hudson Andrade; de Magalhães Soares, Danielle Ferreira; Ribeiro, Múcio Flávio Barbosa; Dos Santos Lima, Walter; Ecco, Roselene
2016-12-01
An adult free-ranged female maned wolf was rescued from a periurban area subject to anthropogenic disturbances in the Minas Gerais, Brazil. The animal presented poor body condition and anemia. The clinical condition rapidly deteriorated culminating in dead and a necropsy was performed. The main gross lesions were marked anemia and blood content in the intestines accompanied by many types of parasites. The protozoa Rangelia vitalii was identified by histopathological analysis predominantly within the cytoplasm of endothelial cells of capillaries of the small intestine. The lymph nodes, spleen, bone marrow, dermis, lungs and kidney had similar protozoal forms but with mild or moderate intensity. Rangelia vitalii was confirmed by molecular assays. Hepatozoon sp., Leishmania sp., and Entamoeba spp., apparently not related to the clinical signs were also detected. The myriad parasites found in the intestines included nematodes ( Ancylostoma caninum , A . braziliensis ,, Molineus sp., Pterygodermatites sp., and Trichuris sp.), cestodes ( Spirometra sp.) and (acanthocephalans. To our knowledge, R . vitalii was identified in C . brachyurus for the first time. These findings emphasize the fragility of Brazilian ecosystems, especially in disturbed areas, reinforcing the necessity of efforts to preserve these areas and wild carnivores, some of which are threatened with extinction, such as the maned wolf.
TOPICAL REVIEW: Self-assembly from milli- to nanoscales: methods and applications
NASA Astrophysics Data System (ADS)
Mastrangeli, M.; Abbasi, S.; Varel, C.; Van Hoof, C.; Celis, J.-P.; Böhringer, K. F.
2009-08-01
The design and fabrication techniques for microelectromechanical systems (MEMS) and nanodevices are progressing rapidly. However, due to material and process flow incompatibilities in the fabrication of sensors, actuators and electronic circuitry, a final packaging step is often necessary to integrate all components of a heterogeneous microsystem on a common substrate. Robotic pick-and-place, although accurate and reliable at larger scales, is a serial process that downscales unfavorably due to stiction problems, fragility and sheer number of components. Self-assembly, on the other hand, is parallel and can be used for device sizes ranging from millimeters to nanometers. In this review, the state-of-the-art in methods and applications for self-assembly is reviewed. Methods for assembling three-dimensional (3D) MEMS structures out of two-dimensional (2D) ones are described. The use of capillary forces for folding 2D plates into 3D structures, as well as assembling parts onto a common substrate or aggregating parts to each other into 2D or 3D structures, is discussed. Shape matching and guided assembly by magnetic forces and electric fields are also reviewed. Finally, colloidal self-assembly and DNA-based self-assembly, mainly used at the nanoscale, are surveyed, and aspects of theoretical modeling of stochastic assembly processes are discussed.
Kaplinsky, C; Kenet, G; Seligsohn, U; Rechavi, G
1998-05-01
A bleeding tendency manifested by petechiae and ecchymoses is one of the most common causes for referral of patients to haematology clinics. Vessel wall pathology is not usually considered to be a cause for deranged haemostasis, although coexistence of increased capillary fragility and joint hypermobility have been reported. We determined the frequency of thumb hyperextensibility and scored the findings in a series of 44 patients referred because of ecchymoses and petechiae, as well as 261 control children and their mothers. All 44 patients had normal coagulation studies. Thumb flexibility score was +4 in 30 patients, +3 in eight patients, +2 in five patients and +1 in one of the index patients. In the control group, only one of 261 had a +4, and three had a +3 score, and two of 260 mothers had a +4 score. Ecchymoses were not observed in any of these subjects, nor in the +1 patients. Based on clinical presentation and normal coagulation studies, we suggest that our patients had an underlying subtype of Ehlers-Danlos syndrome. In view of the dramatically high occurrence of thumb hyperextensibility in patients with unexplained mild bleeding tendency, costly haemostatic and coagulation studies on such patients may not be necessary.
Self-assembly from milli- to nanoscales: methods and applications
Mastrangeli, M; Abbasi, S; Varel, C; Van Hoof, C; Celis, J-P; Böhringer, K F
2009-01-01
The design and fabrication techniques for microelectromechanical systems (MEMS) and nanodevices are progressing rapidly. However, due to material and process flow incompatibilities in the fabrication of sensors, actuators and electronic circuitry, a final packaging step is often necessary to integrate all components of a heterogeneous microsystem on a common substrate. Robotic pick-and-place, although accurate and reliable at larger scales, is a serial process that downscales unfavorably due to stiction problems, fragility and sheer number of components. Self-assembly, on the other hand, is parallel and can be used for device sizes ranging from millimeters to nanometers. In this review, the state-of-the-art in methods and applications for self-assembly is reviewed. Methods for assembling three-dimensional (3D) MEMS structures out of two-dimensional (2D) ones are described. The use of capillary forces for folding 2D plates into 3D structures, as well as assembling parts onto a common substrate or aggregating parts to each other into 2D or 3D structures, is discussed. Shape matching and guided assembly by magnetic forces and electric fields are also reviewed. Finally, colloidal self-assembly and DNA-based self-assembly, mainly used at the nanoscale, are surveyed, and aspects of theoretical modeling of stochastic assembly processes are discussed. PMID:20209016
Device to improve detection in electro-chromatography
Garguilo, Michael G.; Paul, Phillip H.; Rakestraw, David J.
2000-01-01
Apparatus and method for improving the resolution of non-pressure driven capillary chromatographic systems, and particularly for capillary electrochromatography (CEC) systems. By reducing the cross-sectional area of a packed capillary column by means of a second open capillary contiguous with the outlet end of a packed capillary column, where the packed capillary column has a cross sectional area of between about 2 and 5 times that of the open capillary column, the phenomenon of band broadening in the transition region between the open capillary and the packed capillary column, where the individual components of the mixture are analyzed, can be eliminated, thereby providing for a significant improvement in resolution and more accurate detection and analysis.
Device to improve detection in electro-chromatography
Garguilo, Michael G.; Paul, Phillip H.; Rakestraw, David J.
2002-01-01
Apparatus and method for improving the resolution of non-pressure driven capillary chromatographic systems, and particularly for capillary electrochromatography (CEC) systems. By reducing the cross-sectional area of a packed capillary column by means of a second open capillary contiguous with the outlet end of a packed capillary column, where the packed capillary column has a cross sectional area of between about 2 and 5 times that of the open capillary column, the phenomenon of band broadening in the transition region between the open capillary and the packed capillary column, where the individual components of the mixture are analyzed, can be eliminated, thereby providing for a significant improvement in resolution and more accurate detection and analysis.
ERIC Educational Resources Information Center
Kogan, Cary S.; Cornish, Kim M.
2010-01-01
Fragile X Syndrome is a neurodevelopmental disorder that is caused by the silencing of a single gene on the X chromosome, the Fragile X Mental Retardation 1 ("FMR1") gene. In recent years, the premutation ("carrier") status has received considerable attention and there is now an emerging consensus that despite intellectual functioning being within…
Application of Hybrid Geo-Spatially Granular Fragility Curves to Improve Power Outage Predictions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fernandez, Steven J; Allen, Melissa R; Omitaomu, Olufemi A
2014-01-01
Fragility curves depict the relationship between a weather variable (wind speed, gust speed, ice accumulation, precipitation rate) and the observed outages for a targeted infrastructure network. This paper describes an empirical study of the county by county distribution of power outages and one minute weather variables during Hurricane Irene with the objective of comparing 1) as built fragility curves (statistical approach) to engineering as designed (bottom up) fragility curves for skill in forecasting outages during future hurricanes; 2) county specific fragility curves to find examples of significant deviation from average behavior; and 3) the engineering practices of outlier counties tomore » suggest future engineering studies of robustness. Outages in more than 90% of the impacted counties could be anticipated through an average or generic fragility curve. The remaining counties could be identified and handled as exceptions through geographic data sets. The counties with increased or decreased robustness were characterized by terrain more or less susceptible to persistent flooding in areas where above ground poles located their foundations. Land use characteristics of the area served by the power distribution system can suggest trends in the as built power grid vulnerabilities to extreme weather events that would be subjects for site specific studies.« less
Hoyos, Luis R; Thakur, Mili
2017-03-01
Fragile X premutation carriers have 55-200 CGG repeats in the 5' untranslated region of the FMR1 gene. Women with this premutation face many physical and emotional challenges in their life. Approximately 20% of these women will develop fragile X-associated primary ovarian insufficiency (FXPOI). In addition, they suffer from increased rates of menstrual dysfunction, diminished ovarian reserve, reduction in age of menopause, infertility, dizygotic twinning, and risk of having an offspring with a premutation or full mutation. Consequent chronic hypoestrogenism may result in impaired bone health and increased cardiovascular risk. Neuropsychiatric issues include risk of developing fragile X-associated tremor/ataxia syndrome, neuropathy, musculoskeletal problems, increased prevalence of anxiety, depression, and sleep disturbances independent of the stress of raising an offspring with fragile X syndrome and higher risk of postpartum depression. Some studies have reported a higher prevalence of thyroid abnormalities and hypertension in these women. Reproductive health providers play an important role in the health supervision of women with fragile X premutation. Awareness of these risks and correlation of the various manifestations could help in early diagnosis and coordination of care and services for these women and their families. This paper reviews current evidence regarding the possible conditions that may present in women with premutation-sized repeats beyond FXPOI.
Sengupta, Avery; Ghosh, Mahua
2014-01-01
Hypercholesterolemia is a major cause of coronary heart disease. Erythrocyte membrane is affected during hypercholesterolemia. The effect of EPA-DHA rich sterol ester and ALA rich sterol ester on erythrocyte membrane composition, osmotic fragility in normal and hypercholesterolemic rats and changes in antioxidant status of erythrocyte membrane were studied. Erythrocyte membrane composition, osmotic fragility of the membrane and antioxidant enzyme activities was analyzed. Osmotic fragility data suggested that the erythrocyte membrane of hypercholesterolemia was relatively more fragile than that of the normal rats' membrane which could be reversed with the addition of sterol esters in the diet. The increased plasma cholesterol in hypercholesterolemic rats could also be lowered by the sterol ester administration. There was also marked changes in the antioxidant enzyme activities of the erythrocyte membrane. Antioxidant enzyme levels decreased in the membrane of the hypercholesterolemic subjects were increased with the treatment of the sterol esters. The antioxidative activity of ALA rich sterol ester was better in comparison to EPA-DHA rich sterol ester. In conclusion, rat erythrocytes appear to be deformed and became more fragile in cholesterol rich blood. This deformity and fragility was partially reversed by sterol esters by virtue of their ability to lower the extent of hypercholesterolemia.
Development of "fragility" in relaxor ferroelectrics
NASA Astrophysics Data System (ADS)
Wang, Yi-zhen; Chen, Lan; Wang, Hai-yan; Frank Zhang, X.; Fu, Jun; Xiong, Xiao-min; Zhang, Jin-xiu
2014-02-01
Relaxor ferroelectrics (RFs), a special class of the disordered crystals or ceramics, exhibit a pronounced slowdown of their dynamics upon cooling as glass-forming liquids, called the "Super-Arrhenius (SA)" relaxation. Despite great progress in glass-forming liquids, the "fragility" property of the SA relaxation in RFs remains unclear so far. By measuring the temperature-dependent dielectric relaxation in the typical relaxor Pb(Mg1/3Nb2/3)O3-x%PbTiO3 (PMN - x%PT) with 0 ≤ x ≤ 20.0, we in-depth study the "fragility" properties of the SA relaxation in PMN - x%PT. Such fascinating issues as the mechanism of the "fragility" at an atomic scale, the roles of the systematic configurational entropy change and interaction among relaxing units (RUs, including polar nanoregions and free dipoles) and the relation between "fragility" and ferroelectric order are investigated. Our results show that both the "fragility" of the temperature-dependent SA relaxation and ferroelectric order in the PMN - x%PT systems investigated arise thermodynamically from the configurational-entropy loss due to the attractive interaction among RUs, and develops as a power law, possibly diverging at the finite critical temperature Tc. A reasonable physical scenario, based on our "configurational-entropy-loss" theory and Nowick's "stress-induced-ordering" theory, was proposed.
Fragile X mental retardation protein participates in non-coding RNA pathways.
Li, En-Hui; Zhao, Xin; Zhang, Ce; Liu, Wei
2018-02-20
Fragile X syndrome is one of the most common forms of inherited intellectual disability. It is caused by mutations of the Fragile X mental retardation 1(FMR1) gene, resulting in either the loss or abnormal expression of the Fragile X mental retardation protein (FMRP). Recent research showed that FMRP participates in non-coding RNA pathways and plays various important roles in physiology, thereby extending our knowledge of the pathogenesis of the Fragile X syndrome. Initial studies showed that the Drosophila FMRP participates in siRNA and miRNA pathways by interacting with Dicer, Ago1 and Ago2, involved in neural activity and the fate determination of the germline stem cells. Subsequent studies showed that the Drosophila FMRP participates in piRNA pathway by interacting with Aub, Ago1 and Piwi in the maintenance of normal chromatin structures and genomic stability. More recent studies showed that FMRP is associated with lncRNA pathway, suggesting a potential role for the involvement in the clinical manifestations. In this review, we summarize the novel findings and explore the relationship between FMRP and non-coding RNA pathways, particularly the piRNA pathway, thereby providing critical insights on the molecular pathogenesis of Fragile X syndrome, and potential translational applications in clinical management of the disease.
Kover, Sara T.; McDuffie, Andrea; Abbeduto, Leonard; Brown, W. Ted
2012-01-01
Purpose This study examined the impact of sampling context on multiple aspects of expressive language in males with fragile X syndrome in comparison to males with Down syndrome or typical development. Method Participants with fragile X syndrome (n = 27), ages 10 to 17 years, were matched groupwise on nonverbal mental age to adolescents with Down syndrome (n = 15) and typically developing 3- to 6-year-olds (n = 15). Language sampling contexts were an interview-style conversation and narration of a wordless book, with scripted examiner behavior. Language was assessed in terms of amount of talk, MLU of communication unit (MLCU), lexical diversity, fluency, and intelligibility. Results Participants with fragile X syndrome had lower MLCU and lexical diversity than participants with typical development. Participants with Down syndrome produced yet lower MLCU. A differential effect of context among those with fragile X syndrome, Down syndrome, and typical development emerged for the number of attempts per minute, MLCU, and fluency. For participants with fragile X syndrome, autism symptom severity related to the number of utterances produced in conversation. Aspects of examiner behavior related to participant performance. Conclusions Sampling context characteristics should be considered when assessing expressive language in individuals with neurodevelopmental disabilities. PMID:22232386
Murphy, Melissa M; Mazzocco, Michèle M M
2008-01-01
The present study focuses on math and related skills among 32 girls with fragile X (n = 14) or Turner (n = 18) syndrome during late elementary school. Performance in each syndrome group was assessed relative to Full Scale IQ-matched comparison groups of girls from the general population (n = 32 and n = 89 for fragile X syndrome and Turner syndrome, respectively). Differences between girls with fragile X and their comparison group emerged on untimed arithmetic calculations, mastery of counting skills, and arithmetic problem verification accuracy. Relative to girls in the comparison group, girls with Turner syndrome did not differ on untimed arithmetic calculations or problem verification accuracy, but they had limited mastery of counting skills and longer response times to complete the problem verification task. Girls with fragile X or Turner syndrome also differed from their respective comparison groups on math-related abilities, including visual-spatial, working memory, and reading skills, and the associations between math and those related skills. Together, these findings support the notion that difficulty with math and related skills among girls with fragile X or Turner syndrome continues into late elementary school and that the profile of math and related skill difficulty distinguishes the two syndrome groups from each other.
Sheathless interface for coupling capillary electrophoresis with mass spectrometry
Wang, Chenchen; Tang, Keqi; Smith, Richard D.
2014-06-17
A sheathless interface for coupling capillary electrophoresis (CE) with mass spectrometry is disclosed. The sheathless interface includes a separation capillary for performing CE separation and an emitter capillary for electrospray ionization. A portion of the emitter capillary is porous or, alternatively, is coated to form an electrically conductive surface. A section of the emitter capillary is disposed within the separation capillary, forming a joint. A metal tube, containing a conductive liquid, encloses the joint.
Biancalana, Valérie; Glaeser, Dieter; McQuaid, Shirley; Steinbach, Peter
2015-01-01
Different mutations occurring in the unstable CGG repeat in 5' untranslated region of FMR1 gene are responsible for three fragile X-associated disorders. An expansion of over ∼200 CGG repeats when associated with abnormal methylation and inactivation of the promoter is the mutation termed ‘full mutation' and is responsible for fragile X syndrome (FXS), a neurodevelopmental disorder described as the most common cause of inherited intellectual impairment. The term ‘abnormal methylation' is used here to distinguish the DNA methylation induced by the expanded repeat from the ‘normal methylation' occurring on the inactive X chromosomes in females with normal, premutation, and full mutation alleles. All male and roughly half of the female full mutation carriers have FXS. Another anomaly termed ‘premutation' is characterized by the presence of 55 to ∼200 CGGs without abnormal methylation, and is the cause of two other diseases with incomplete penetrance. One is fragile X-associated primary ovarian insufficiency (FXPOI), which is characterized by a large spectrum of ovarian dysfunction phenotypes and possible early menopause as the end stage. The other is fragile X-associated tremor/ataxia syndrome (FXTAS), which is a late onset neurodegenerative disorder affecting males and females. Because of the particular pattern and transmission of the CGG repeat, appropriate molecular testing and reporting is very important for the optimal genetic counselling in the three fragile X-associated disorders. Here, we describe best practice guidelines for genetic analysis and reporting in FXS, FXPOI, and FXTAS, including carrier and prenatal testing. PMID:25227148
Lozano, Reymundo; Rosero, Carolina Alba; Hagerman, Randi J
2014-01-01
Summary The fragile X mental retardation 1 gene (FMR1), which codes for the fragile X mental retardation 1 protein (FMRP), is located at Xp27.3. The normal allele of the FMR1 gene typically has 5 to 40 CGG repeats in the 5′ untranslated region; abnormal alleles of dynamic mutations include the full mutation (> 200 CGG repeats), premutation (55–200 CGG repeats) and the gray zone mutation (45–54 CGG repeats). Premutation carriers are common in the general population with approximately 1 in 130–250 females and 1 in 250–810 males, whereas the full mutation and Fragile X syndrome (FXS) occur in approximately 1 in 4000 to 1 in 7000. FMR1 mutations account for a variety of phenotypes including the most common monogenetic cause of inherited intellectual disability (ID) and autism (FXS), the most common genetic form of ovarian failure, the fragile X-associated primary ovarian insufficiency (FXPOI, premutation); and fragile X-associated tremor/ataxia syndrome (FXTAS, premutation). The premutation can also cause developmental problems including ASD and ADHD especially in boys and psychopathology including anxiety and depression in children and adults. Some premutation carriers can have a deficit of FMRP and some unmethylated full mutation individuals can have elevated FMR1 mRNA that is considered a premutation problem. Therefore the term “Fragile X Spectrum Disorder” (FXSD) should be used to include the wide range of overlapping phenotypes observed in affected individuals with FMR1 mutations. In this review we focus on the phenotypes and genotypes of children with FXSD. PMID:25606363
Iolascon, Giovanni; Moretti, Antimo; Giamattei, Maria Teresa; Migliaccio, Silvia; Gimigliano, Francesca
2015-10-01
Fragility fractures are a major burden for health and social care in elderly people. In order to identify earlier the "frail elders", new concepts of "dysmobility syndrome" and skeletal muscle function deficit (SMFD), including sarcopenia, osteoporosis, obesity, and mobility limitation, leading to a higher risk of fractures, have been recently introduced. There are very few studies investigating the association between fragility fractures and both the dysmobility syndrome and the SMFD. The objective of our study is to investigate the role of previous fragility fractures as a risk factor in determining the dysmobility syndrome and/or the SMFD in post-menopausal women. In this case-control study, we retrospectively examined data from the medical records of post-menopausal women aged 50 or older. We divided the study population in two groups. The first group includes women with a previous fragility fracture (cases) and the other group includes women without any previous osteoporotic fracture (controls). We identified the subjects with "dysmobility syndrome", "dynapenic SMFD", "sarcopenic SMFD", and "mixed SMFD" in both groups. Data collected refer to a 6-month period. We retrieved data of 121 post-menopausal women, 77 (63.64%) had already sustained a fragility fracture at any site (cases). The risk for dysmobility syndrome was significantly higher (adjusted OR for age and serum 25-OH vitamin D3 of 2.46) in the cases compared with the controls. An early diagnosis of conditions limiting mobility, including dysmobility syndrome, might be useful to identify, among patients with osteoporotic fractures, those who might have a higher risk of a new fragility fracture.
Design of Capillary Flows with Spatially Graded Porous Films
NASA Astrophysics Data System (ADS)
Joung, Young Soo; Figliuzzi, Bruno Michel; Buie, Cullen
2013-11-01
We have developed a new capillary tube model, consisting of multi-layered capillary tubes oriented in the direction of flow, to predict capillary speeds on spatially graded porous films. Capillary flows through thin porous media have been widely utilized for small size liquid transport systems. However, for most media it is challenging to realize arbitrary shapes and spatially functionalized micro-structures with variable flow properties. Therefore, conventional media can only be used for capillary flows obeying Washburn's equation and the modifications thereof. Given this background, we recently developed a method called breakdown anodization (BDA) to produce highly wetting porous films. The resulting surfaces show nearly zero contact angles and fast water spreading speed. Furthermore, capillary pressure and spreading diffusivity can be expressed as functions of capillary height when customized electric fields are used in BDA. From the capillary tube model, we derived a general capillary flow equation of motion in terms of capillary pressure and spreading diffusivity. The theoretical model shows good agreement with experimental capillary flows. The study will provide novel design methodologies for paper-based microfluidic devices.
Iliff, Adam J.; Renoux, Abigail J.; Krans, Amy; Usdin, Karen; Sutton, Michael A.; Todd, Peter K.
2013-01-01
Fragile X premutation-associated disorders, including Fragile X-associated Tremor Ataxia Syndrome, result from unmethylated CGG repeat expansions in the 5′ untranslated region (UTR) of the FMR1 gene. Premutation-sized repeats increase FMR1 transcription but impair rapid translation of the Fragile X mental retardation protein (FMRP), which is absent in Fragile X Syndrome (FXS). Normally, FMRP binds to RNA and regulates metabotropic glutamate receptor (mGluR)-mediated synaptic translation, allowing for dendritic synthesis of several proteins. FMRP itself is also synthesized at synapses in response to mGluR activation. However, the role of activity-dependent translation of FMRP in synaptic plasticity and Fragile X-premutation-associated disorders is unknown. To investigate this question, we utilized a CGG knock-in mouse model of the Fragile X premutation with 120–150 CGG repeats in the mouse Fmr1 5′ UTR. These mice exhibit increased Fmr1 mRNA production but impaired FMRP translational efficiency, leading to a modest reduction in basal FMRP expression. Cultured hippocampal neurons and synaptoneurosomes derived from CGG KI mice demonstrate impaired FMRP translation in response to the group I mGluR agonist 3,5-dihydroxyphenylglycine. Electrophysiological analysis reveals enhanced mGluR-mediated long-term depression (mGluR-LTD) at CA3–CA1 synapses in acute hippocampal slices prepared from CGG KI mice relative to wild-type littermates, similar to Fmr1 knockout mice. However, unlike mGluR-LTD in mice completely lacking FMRP, mGluR-LTD in CGG knock-in mice remains dependent on new protein synthesis. These studies demonstrate partially overlapping synaptic plasticity phenotypes in mouse models of FXS and Fragile X premutation disorders and support a role for activity-dependent synthesis of FMRP in enduring forms of synaptic plasticity. PMID:23250915
Fragile X checklists: A meta-analysis and development of a simplified universal clinical checklist.
Lubala, Toni Kasole; Lumaka, Aimé; Kanteng, Gray; Mutesa, Léon; Mukuku, Olivier; Wembonyama, Stanislas; Hagerman, Randi; Luboya, Oscar Numbi; Lukusa Tshilobo, Prosper
2018-04-06
Clinical checklists available have been developed to assess the risk of a positive Fragile X syndrome but they include relatively small sample sizes. Therefore, we carried out a meta-analysis that included statistical pooling of study results to obtain accurate figures on the prevalence of clinical predictors of Fragile X syndrome among patients with intellectual disability, thereby helping health professionals to improve their referrals for Fragile X testing. All published studies consisting of cytogenetic and/or molecular screening for fragile X syndrome among patients with intellectual disability, were eligible for the meta-analysis. All patients enrolled in clinical checklists trials of Fragile X syndrome were eligible for this review, with no exclusion based on ethnicity or age. Odds ratio values, with 95% confidence intervals as well as Cronbach coefficient alpha, was reported to assess the frequency of clinical characteristics in subjects with intellectual disability with and without the fragile X mutation to determine the most discriminating. The following features were strongly associated with Fragile X syndrome: skin soft and velvety on the palms with redundancy of skin on the dorsum of hand [OR: 16.85 (95% CI 10.4-27.3; α:0.97)], large testes [OR: 7.14 (95% CI 5.53-9.22; α: 0.80)], large and prominent ears [OR: 18.62 (95% CI 14.38-24.1; α: 0.98)], pale blue eyes [OR: 8.97 (95% CI 4.75-16.97; α: 0.83)], family history of intellectual disability [OR: 3.43 (95% CI 2.76-4.27; α: 0.81)] as well as autistic-like behavior [OR: 3.08 (95% CI 2.48-3.83; α: 0.77)], Flat feet [OR: 11.53 (95% CI 6.79-19.56; α:0.91)], plantar crease [OR: 3.74 (95% CI 2.67-5.24; α: 0.70)]. We noted a weaker positive association between transverse palmar crease [OR: 2.68 (95% CI 1.70-4.18; α: 0.51)], elongated face [OR: 3.69 (95% CI 2.84-4.81; α: 0.63)]; hyperextensible metacarpo-phalangeal joints [OR: 2.68 (95% CI 2.15-3.34; α: 0.57)] and the Fragile X syndrome. This study has identified the highest risk features for patients with Fragile X syndrome that have been used to design a universal clinical checklist. © 2018 The Authors. Molecular Genetics & Genomic Medicine published by Wiley Periodicals, Inc.
Glancy, Brian; Hsu, Li-Yueh; Dao, Lam; Bakalar, Matthew; French, Stephanie; Chess, David J.; Taylor, Joni L.; Picard, Martin; Aponte, Angel; Daniels, Mathew P.; Esfahani, Shervin; Cushman, Samuel; Balaban, Robert S.
2013-01-01
Objective To provide insight into mitochondrial function in vivo, we evaluated the 3D spatial relationship between capillaries, mitochondria, and muscle fibers in live mice. Methods 3D volumes of in vivo murine Tibialis anterior muscles were imaged by multi-photon microscopy (MPM). Muscle fiber type, mitochondrial distribution, number of capillaries, and capillary-to-fiber contact were assessed. The role of myoglobin-facilitated diffusion was examined in myoglobin knockout mice. Distribution of GLUT4 was also evaluated in the context of the capillary and mitochondrial network. Results MPM revealed that 43.6 ± 3.3% of oxidative fiber capillaries had ≥ 50% of their circumference embedded in a groove in the sarcolemma, in vivo. Embedded capillaries were tightly associated with dense mitochondrial populations lateral to capillary grooves and nearly absent below the groove. Mitochondrial distribution, number of embedded capillaries, and capillary-to-fiber contact were proportional to fiber oxidative capacity and unaffected by myoglobin knockout. GLUT4 did not preferentially localize to embedded capillaries. Conclusions Embedding capillaries in the sarcolemma may provide a regulatory mechanism to optimize delivery of oxygen to heterogeneous groups of muscle fibers. We hypothesize that mitochondria locate to paravascular regions due to myofibril voids created by embedded capillaries, not to enhance the delivery of oxygen to the mitochondria. PMID:25279425
Targeted Upregulation of FMRP Expression as an Approach to the Treatment of Fragile X Syndrome
2016-10-01
Fragile X syndrome (FXS), the most common heritable form of intellectual disability and most common single-gene form of autism , is caused by partial...15. SUBJECT TERMS Fragile X, autism , FMR1, FXTAS, CGG repeat, epilepsy, seizures, FMRP, PTSD, premutation, iPSC, progenitor, calcium regulation...the most common heritable form of intellectual disability, the most common single-gene form of autism , and a relatively common cause of epilepsy
2013-04-01
epilepsy, autism , anxiety and mood disorders. Fragile X syndrome (FXS), another form of inherited mental retardation and autism , shares many of the...therapeutic intervention for several of the deficits observed in TSC. 15. SUBJECT TERMS autism , Tuberous Sclerosis Complex, Fragile X Syndrome...clinical features being mental retardation, epilepsy, autism , anxiety and mood disorders (Prather & de Vries, 2004). Fragile X syndrome (FXS
Germline mosaicism at the fragile X locus
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prior, T.W.; Papp, A.C.; Snyder, P.J.
We have identified a fragile X syndrome pedigree where the disorder is associated with a molecular deletion. The deletion was present in the DNA of 2 sons but was absent in the mother`s somatic cell (lymphocyte) DNA. The results are consistent with the deletion arising as a postzygotic event in the mother, who therefore is germinally mosaic. This finding has important implications for counseling fragile X families with deletion mutations. 13 refs., 2 figs.
ERIC Educational Resources Information Center
Santos, Ana Rita; Kanellopoulos, Alexandros K.; Bagni, Claudia
2014-01-01
The Fragile X syndrome (FXS) is the most frequent form of inherited mental disability and is considered a monogenic cause of autism spectrum disorder. FXS is caused by a triplet expansion that inhibits the expression of the "FMR1" gene. The gene product, the Fragile X Mental Retardation Protein (FMRP), regulates mRNA metabolism in brain…
ERIC Educational Resources Information Center
Richardson, Lolita Lisa
2010-01-01
This study investigated the relationship between repetitive behaviors and sensory behavior to the parenting stress of mothers of boys with fragile X syndrome and mothers of boys with autism. Participants consisted of two groups: 51 mothers with boys diagnosed with fragile X syndrome (M = 71.3, SD = 56.5) and 30 mothers with boys diagnosed with…
Chen, Xingguo; Fazal, Md. Abul; Dovichi, Norman J.
2007-01-01
Two-dimensional capillary electrophoresis was used for the separation of proteins and biogenic amines from the mouse AtT-20 cell line. The first-dimension capillary contained a TRIS-CHES-SDS-dextran buffer to perform capillary sieving electrophoresis, which is based on molecular weight of proteins. The second-dimension capillary contained a TRIS-CHES-SDS buffer for micel1ar electrokinetic capillary chromatography. After a 61 seconds preliminary separation, fractions from the first-dimension capillary were successively transferred to the second-dimension capillary, where they further separated by MECC. The two-dimensional separation required 60 minutes. PMID:17637850
Mettyas, Tamer; Carpenter, Clare
2013-12-01
Osteoporosis is one of the commonest bone diseases in which bone fragility is increased. Over 300,000 patients present to hospitals in the UK with fragility fractures each year, with medical and social care costs - most of which relate to hip fracture care - at around £2 billion. The number of these fractures rises by 2% a year. The 30 days mortality is 10% and 30% at 1 year. The purpose of this study is to review the current practice according to NICE and BOA guidelines of secondary prevention of osteoporosis and to suggest changes to these guidelines. Patients over 50 years old admitted as inpatients to our facility with non-neck-of-femur (NOF) fragility fractures in March and September 2008 were studied. Retrospectively (March), looking for risk factors and if treated or not, then prospectively (September), after introducing the new trauma admission sheet. Also cross-sectional study was performed by comparing the services provided for NOF and non-NOF fragility fractures in September. Two-sample t test is used to compare between percentages. Twenty-nine percent of fragility fractures are non-NOF fractures with a mean age of 70 years, while the remaining 71% are NOF fractures with a mean age of 80 years. There is a great difference in the care provided to these patients: non-NOF fragility fractures got less attention for assessment of osteoporosis (25%) and obtained less interest in investigations by medical staff (11%) and, finally, less intentions to treat osteoporosis (35%), compared to NOF fractures in which 35% of cases were assessed, 47% were investigated and 71% were treated for osteoporosis. Twenty-five percent of NOF fracture patients were found to have previous fragility fractures in the preceding years, while only 6% were on osteoporosis treatment before the fracture. Osteoporosis (a new epidemic) is the most common disease of the bone and its incidence is rising rapidly as the population ages. Though treatable, it is often left untreated. We believe that treating patients with non-NOF fragility fractures from osteoporosis before proceeding to NOF fractures would improve their quality of life and reduce the burden on hospital services and funding.
Milovanovic, Petar; Vukovic, Zorica; Antonijevic, Djordje; Djonic, Danijela; Zivkovic, Vladimir; Nikolic, Slobodan; Djuric, Marija
2017-05-01
Bone is a remarkable biological nanocomposite material showing peculiar hierarchical organization from smaller (nano, micro) to larger (macro) length scales. Increased material porosity is considered as the main feature of fragile bone at larger length-scales. However, there is a shortage of quantitative information on bone porosity at smaller length-scales, as well as on the distribution of pore sizes in healthy vs. fragile bone. Therefore, here we investigated how healthy and fragile bones differ in pore volume and pore size distribution patterns, considering a wide range of mostly neglected pore sizes from nano to micron-length scales (7.5 to 15000 nm). Cortical bone specimens from four young healthy women (age: 35 ± 6 years) and five women with bone fracture (age: 82 ± 5 years) were analyzed by mercury porosimetry. Our findings showed that, surprisingly, fragile bone demonstrated lower pore volume at the measured scales. Furtnermore, pore size distribution showed differential patterns between healthy and fragile bones, where healthy bone showed especially high proportion of pores between 200 and 15000 nm. Therefore, although fragile bones are known for increased porosity at macroscopic level and level of tens or hundreds of microns as firmly established in the literature, our study with a unique assessment range of nano-to micron-sized pores reveal that osteoporosis does not imply increased porosity at all length scales. Our thorough assessment of bone porosity reveals a specific distribution of porosities at smaller length-scales and contributes to proper understanding of bone structure which is important for designing new biomimetic bone substitute materials.
Usala, Rachel L; Fernandez, Stephen J; Mete, Mihriye; Cowen, Laura; Shara, Nawar M; Barsony, Julianna; Verbalis, Joseph G
2015-08-01
The significance of studies suggesting an increased risk of bone fragility fractures with hyponatremia through mechanisms of induced bone loss and increased falls has not been demonstrated in large patient populations with different types of hyponatremia. This matched case-control study evaluated the effect of hyponatremia on osteoporosis and fragility fractures in a patient population of more than 2.9 million. Osteoporosis (n = 30 517) and fragility fracture (n = 46 256) cases from the MedStar Health database were matched on age, sex, race, and patient record length with controls without osteoporosis (n = 30 517) and without fragility fractures (n = 46 256), respectively. Cases without matched controls or serum sodium (Na(+)) data or with Na(+) with a same-day blood glucose greater than 200 mg/dL were excluded. Incidence of diagnosis of osteoporosis and fragility fractures of the upper or lower extremity, pelvis, and vertebrae were the outcome measures. Multivariate conditional logistic regression models demonstrated that hyponatremia was associated with osteoporosis and/or fragility fractures, including chronic [osteoporosis: odds ratio (OR) 3.97, 95% confidence interval (CI) 3.59-4.39; fracture: OR 4.61, 95% CI 4.15-5.11], recent (osteoporosis: OR 3.06, 95% CI 2.81-3.33; fracture: OR 3.05, 95% CI 2.83-3.29), and combined chronic and recent hyponatremia (osteoporosis: OR 12.09, 95% CI 9.34-15.66; fracture: OR 11.21, 95% CI 8.81-14.26). Odds of osteoporosis or fragility fracture increased incrementally with categorical decrease in median serum Na(+). These analyses support the hypothesis that hyponatremia is a risk factor for osteoporosis and fracture. Additional studies are required to evaluate whether correction of hyponatremia will improve patient outcomes.
de Boer, Michiel P; Meijer, Rick I; Newman, John; Stehouwer, Coen D A; Eringa, Etto C; Smulders, Yvo M; Serné, Erik H
2014-07-01
Insulin-induced capillary recruitment is considered a significant regulator of overall insulin-stimulated glucose uptake. Insulin's action to recruit capillaries has been hypothesized to involve insulin-induced changes in vasomotion. Data directly linking vasomotion to capillary perfusion, however, are presently lacking. We, therefore, investigated whether insulin's actions on capillary recruitment and vasomotion were interrelated in a group of healthy individuals. We further assessed the role of capillary recruitment in the association between vasomotion and insulin-mediated glucose uptake. Changes in vasomotion and capillary density were determined by LDF and capillary videomicroscopy in skin, respectively, before and during a hyperinsulinemic euglycemic clamp in 19 healthy volunteers. Insulin-induced increase in the neurogenic vasomotion domain was positively related to insulin-augmented capillary recruitment (r = 0.51, p = 0.04), and both parameters were related to insulin-mediated glucose uptake (r = 0.47, p = 0.06 and r = 0.73, p = 0.001, respectively). The change in insulin-augmented capillary recruitment could, at least statistically, largely explain the association between the neurogenic domain and insulin-mediated glucose uptake. Insulin-induced changes in vasomotion and capillary recruitment are associated in healthy volunteers. These data suggest that insulin's action to recruit capillaries may in part involve action on the neurogenic vasomotion domain, thereby enhancing capillary perfusion and glucose uptake. © 2014 John Wiley & Sons Ltd.
Translation of Novel Serotonin 5-HT7 Agonist Drug Candidates in Rodent Models of Fragile X Syndrome
2016-09-01
President of DELSIA (Delivering Science Innovation for Autism ) and Vice President, Innovative Technologies at Autism Speaks, Daniel Smith, who...in autism and Fragile X syndrome. Notably, there are no 9 pharmacotherapies approved for core symptoms of autism or Fragile X syndrome, thus, our...HT1A partial agonist for autism . 6th Cisbio HTRF symposium (Brewster, MA), September 14-17, 2015. Acknowledged DOD funding. Teaching Lectures. 10
NASA Astrophysics Data System (ADS)
Zhang, Lanhe; Elupula, Ravinder; Grayson, Scott; Torkelson, John
Cyclic or ring polymers represent an exciting class of topologically distinctive polymers. The influence of ``end-to-end'' tethering and the unusual conformational properties associated with cyclic topologies have led to polymer dynamics significantly different from the linear counterpart. Bulk cyclic polystyrene (c-PS) exhibits very weak Tg- and fragility-molecular weight (MW) dependences compared to linear PS. In stark contrast to the substantial Tg-confinement effects in linear PS, a nearly completely suppressed confinement effect is discovered in low MW c-PS. The cyclic topology strongly restricts polymer-substrate interactions. Therefore, the near elimination of the Tg-confinement effect in c-PS originates mainly from a very weak perturbation to Tg near the free surface. Upon nanoscale confinement, linear PS films have been shown to have significantly reduced fragility compared to bulk. Despite having similar bulk fragility as high MW linear PS, low MW c-PS films show major suppression in fragility reduction with decreasing thickness. Due to a lack of chain ends, properties associated with the ring structure are not prone to be perturbed by either MW reduction or confinement. This result indicates a strong correlation between the susceptibility of fragility perturbation and the susceptibility of Tg perturbation, caused by chain topology and/or by confinement. This work was supported by The Dow Chemical Company, a McCormick School of Engineering Fellowship, and the NSF.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Adichtchev, S. V.; Malinovsky, V. K.; Surovtsev, N. V., E-mail: lab21@iae.nsk.su
Low-frequency (down to 30 GHz) inelastic light scattering is studied in a multicomponent glass ZBLAN (ZrF{sub 4}-BaF{sub 2}-LaF{sub 3}-AlF{sub 3}-NaF) in a wide temperature range. The contributions of the THz vibrational spectrum (boson peak) and of the fast relaxation are extracted and analyzed. It is shown that the fast relaxation spectrum is described by a distribution of relaxation times leading to a power-law ν{sup α} dependence in the frequency range 30–300 GHz. Temperature dependence of α(T) is well described by the Gilroy-Phillips model, while the integrated intensity of the fast relaxation increases significantly with the temperature. This feature distinguishes themore » fast relaxation in ZBLAN from the case of most single-component glasses. Thermodynamic and kinetic fragility indexes are significantly different for the ZBLAN glass. The correlations between the boson peak intensity, elastic moduli, and fragility index, found earlier for single-component glasses, are fulfilled for the thermodynamic fragility index of ZBLAN. In contrast, the correlation between the fast relaxation intensity at T{sub g} and the fragility holds better for the kinetic fragility index of ZBLAN. We propose that thermodynamic and kinetic fragilities reflect different aspects of glassy dynamics in the case of glass formers with the complex chemical composition and structure topology: the former correlates with the elastic properties and the boson peak, the latter with the relaxation.« less
Why glass elasticity affects the thermodynamics and fragility of supercooled liquids
Yan, Le; Düring, Gustavo; Wyart, Matthieu
2013-01-01
Supercooled liquids are characterized by their fragility: The slowing down of the dynamics under cooling is more sudden and the jump of specific heat at the glass transition is generally larger in fragile liquids than in strong ones. Despite the importance of this quantity in classifying liquids, explaining what aspects of the microscopic structure controls fragility remains a challenge. Surprisingly, experiments indicate that the linear elasticity of the glass—a purely local property of the free energy landscape—is a good predictor of fragility. In particular, materials presenting a large excess of soft elastic modes, the so-called boson peak, are strong. This is also the case for network liquids near the rigidity percolation, known to affect elasticity. Here we introduce a model of the glass transition based on the assumption that particles can organize locally into distinct configurations that are coupled spatially via elasticity. The model captures the mentioned observations connecting elasticity and fragility. We find that materials presenting an abundance of soft elastic modes have little elastic frustration: Energy is insensitive to most directions in phase space, leading to a small jump of specific heat. In this framework strong liquids turn out to lie the closest to a critical point associated with a rigidity or jamming transition, and their thermodynamic properties are related to the problem of number partitioning and to Hopfield nets in the limit of small memory. PMID:23576746
Why glass elasticity affects the thermodynamics and fragility of supercooled liquids.
Yan, Le; Düring, Gustavo; Wyart, Matthieu
2013-04-16
Supercooled liquids are characterized by their fragility: The slowing down of the dynamics under cooling is more sudden and the jump of specific heat at the glass transition is generally larger in fragile liquids than in strong ones. Despite the importance of this quantity in classifying liquids, explaining what aspects of the microscopic structure controls fragility remains a challenge. Surprisingly, experiments indicate that the linear elasticity of the glass--a purely local property of the free energy landscape--is a good predictor of fragility. In particular, materials presenting a large excess of soft elastic modes, the so-called boson peak, are strong. This is also the case for network liquids near the rigidity percolation, known to affect elasticity. Here we introduce a model of the glass transition based on the assumption that particles can organize locally into distinct configurations that are coupled spatially via elasticity. The model captures the mentioned observations connecting elasticity and fragility. We find that materials presenting an abundance of soft elastic modes have little elastic frustration: Energy is insensitive to most directions in phase space, leading to a small jump of specific heat. In this framework strong liquids turn out to lie the closest to a critical point associated with a rigidity or jamming transition, and their thermodynamic properties are related to the problem of number partitioning and to Hopfield nets in the limit of small memory.
Repeat-mediated epigenetic dysregulation of the FMR1 gene in the fragile X-related disorders.
Usdin, Karen; Kumari, Daman
2015-01-01
The fragile X-related disorders are members of the Repeat Expansion Diseases, a group of genetic conditions resulting from an expansion in the size of a tandem repeat tract at a specific genetic locus. The repeat responsible for disease pathology in the fragile X-related disorders is CGG/CCG and the repeat tract is located in the 5' UTR of the FMR1 gene, whose protein product FMRP, is important for the proper translation of dendritic mRNAs in response to synaptic activation. There are two different pathological FMR1 allele classes that are distinguished only by the number of repeats. Premutation alleles have 55-200 repeats and confer risk of fragile X-associated tremor/ataxia syndrome and fragile X-associated primary ovarian insufficiency. Full mutation alleles on the other hand have >200 repeats and result in fragile X syndrome, a disorder that affects learning and behavior. Different symptoms are seen in carriers of premutation and full mutation alleles because the repeat number has paradoxical effects on gene expression: Epigenetic changes increase transcription from premutation alleles and decrease transcription from full mutation alleles. This review will cover what is currently known about the mechanisms responsible for these changes in FMR1 expression and how they may relate to other Repeat Expansion Diseases that also show repeat-mediated changes in gene expression.
Rajan-Babu, Indhu-Shree; Lian, Mulias; Cheah, Felicia S H; Chen, Min; Tan, Arnold S C; Prasath, Ethiraj B; Loh, Seong Feei; Chong, Samuel S
2017-07-19
Fragile X mental retardation 1 (FMR1) full-mutation expansion causes fragile X syndrome. Trans-generational fragile X syndrome transmission can be avoided by preimplantation genetic diagnosis (PGD). We describe a robust PGD strategy that can be applied to virtually any couple at risk of transmitting fragile X syndrome. This novel strategy utilises whole-genome amplification, followed by triplet-primed polymerase chain reaction (TP-PCR) for robust detection of expanded FMR1 alleles, in parallel with linked multi-marker haplotype analysis of 13 highly polymorphic microsatellite markers located within 1 Mb of the FMR1 CGG repeat, and the AMELX/Y dimorphism for gender identification. The assay was optimised and validated on single lymphoblasts isolated from fragile X reference cell lines, and applied to a simulated PGD case and a clinical in vitro fertilisation (IVF)-PGD case. In the simulated PGD case, definitive diagnosis of the expected results was achieved for all 'embryos'. In the clinical IVF-PGD case, delivery of a healthy baby girl was achieved after transfer of an expansion-negative blastocyst. FMR1 TP-PCR reliably detects presence of expansion mutations and obviates reliance on informative normal alleles for determining expansion status in female embryos. Together with multi-marker haplotyping and gender determination, misdiagnosis and diagnostic ambiguity due to allele dropout is minimised, and couple-specific assay customisation can be avoided.
Comparison of main-shock and aftershock fragility curves developed for New Zealand and US buildings
Uma, S.R.; Ryu, H.; Luco, N.; Liel, A.B.; Raghunandan, M.
2011-01-01
Seismic risk assessment involves the development of fragility functions to express the relationship between ground motion intensity and damage potential. In evaluating the risk associated with the building inventory in a region, it is essential to capture 'actual' characteristics of the buildings and group them so that 'generic building types' can be generated for further analysis of their damage potential. Variations in building characteristics across regions/countries largely influence the resulting fragility functions, such that building models are unsuitable to be adopted for risk assessment in any other region where a different set of building is present. In this paper, for a given building type (represented in terms of height and structural system), typical New Zealand and US building models are considered to illustrate the differences in structural model parameters and their effects on resulting fragility functions for a set of main-shocks and aftershocks. From this study, the general conclusion is that the methodology and assumptions used to derive basic capacity curve parameters have a considerable influence on fragility curves.
Seismic fragility curves of bridge piers accounting for ground motions in Korea
NASA Astrophysics Data System (ADS)
Nguyen, Duy-Duan; Lee, Tae-Hyung
2018-04-01
Korea is located in a slight-to-moderate seismic zone. Nevertheless, several studies pointed that the peak earthquake magnitude in the region can be reached to approximately 6.5. Accordingly, a seismic vulnerability evaluation of the existing structures accounting for ground motions in Korea is momentous. The purpose of this paper is to develop seismic fragility curves for bridge piers of a steel box girder bridge equipped with and without base isolators based on a set of ground motions recorded in Korea. A finite element simulation platform, OpenSees, is utilized to perform nonlinear time history analyses of the bridges. A series of damage states is defined based on a damage index which is expressed in terms of the column displacement ductility ratio. The fragility curves based on Korean motions were thereafter compared with the fragility curves generated using worldwide earthquakes to assess the effect of the two ground motion groups on the seismic fragility curves of the bridge piers. The results reveal that both non- and base-isolated bridge piers are less vulnerable during the Korean ground motions than that under worldwide earthquakes.
Hippocampal dysfunction and cognitive impairment in Fragile-X Syndrome.
Bostrom, Crystal; Yau, Suk-Yu; Majaess, Namat; Vetrici, Mariana; Gil-Mohapel, Joana; Christie, Brian R
2016-09-01
Fragile-X Syndrome (FXS) is the most common form of inherited intellectual disability and the leading genetic cause of autism spectrum disorder. FXS is caused by transcriptional silencing of the Fragile X Mental Retardation 1 (Fmr1) gene due to a CGG repeat expansion, resulting in the loss of Fragile X Mental Retardation Protein (FMRP). FMRP is involved in transcriptional regulation and trafficking of mRNA from the nucleus to the cytoplasm and distal sites both in pre- and post-synaptic terminals. Consequently, FXS is a multifaceted disorder associated with impaired synaptic plasticity. One region of the brain that is significantly impacted by the loss of FMRP is the hippocampus, a structure that plays a critical role in the regulation of mood and cognition. This review provides an overview of the neuropathology of Fragile-X Syndrome, highlighting how structural and synaptic deficits in hippocampal subregions, including the CA1 exhibiting exaggerated metabotropic glutamate receptor dependent long-term depression and the dentate gyrus displaying hypofunction of N-methyl-d-aspartate receptors, contribute to cognitive impairments associated with this neurodevelopmental disorder. Copyright © 2016 Elsevier Ltd. All rights reserved.
Chavassieux, P; Seeman, E; Delmas, P D
2007-04-01
Minimal trauma fractures in bone diseases are the result of bone fragility. Rather than considering bone fragility as being the result of a reduced amount of bone, we recognize that bone fragility is the result of changes in the material and structural properties of bone. A better understanding of the contribution of each component of the material composition and structure and how these interact to maintain whole bone strength is obtained by the study of metabolic bone diseases. Disorders of collagen (osteogenesis imperfecta and Paget's disease of bone), mineral content, composition and distribution (fluorosis and osteomalacia); diseases of high remodeling (postmenopausal osteoporosis, hyperparathyroidism, and hyperthyroidism) and low remodeling (osteopetrosis, pycnodysostosis); and other diseases (idiopathic male osteoporosis, corticosteroid-induced osteoporosis) produce abnormalities in the material composition and structure that lead to bone fragility. Observations in patients and in animal models provide insights on the biomechanical consequences of these illnesses and the nature of the qualities of bone that determine its strength.
Mathematics learning disability in girls with Turner syndrome or fragile X syndrome.
Murphy, Melissa M; Mazzocco, Michèle M M; Gerner, Gwendolyn; Henry, Anne E
2006-07-01
Two studies were carried out to examine the persistence (Study 1) and characteristics (Study 2) of mathematics learning disability (MLD) in girls with Turner syndrome or fragile X during the primary school years (ages 5-9 years). In Study 1, the rate of MLD for each syndrome group exceeded the rate observed in a grade-matched comparison group, although the likelihood of MLD persisting through the primary school years was comparable for all three groups. In Study 2, formal and informal math skills were compared across the syndrome groups, a normative group, and children from the normative group who had MLD. Few differences were observed between the Turner syndrome and normative groups. Despite having rote counting and number representation skills comparable to those in the normative group, girls with fragile X had difficulty with counting rules (e.g., cardinality, number constancy). However, this difficulty did not distingush them from the MLD group. Overall, counting skills appear to distinguish the Turner syndrome and fragile X groups, suggesting that the specificity of math deficits emerges earlier for fragile X than Turner syndrome.
Effect of Capillary Tube’s Shape on Capillary Rising Regime for Viscos Fluids
NASA Astrophysics Data System (ADS)
Soroush, F.; Moosavi, A.
2018-05-01
When properties of the displacing fluid are considered, the rising profile of the penetrating fluid in a capillary tube deviates from its classical Lucas-Washburn profile. Also, shape of capillary tube can affect the rising profile in different aspects. In this article, effect of capillary tube’s shape on the vertical capillary motion in presence of gravity is investigated by considering the properties of the displacing fluid. According to the fact that the differential equation of the capillary rising for a non-simple wall type is very difficult to solve analytically, a finite element simulation model is used for this study. After validation of the simulation model with an experiment that has been done with a simple capillary tube, shape of the capillary tube’s wall is changed in order to understand its effects on the capillary rising and different motion regimes that may appear according to different geometries. The main focus of this article is on the sinusoidal wall shapes and comparing them with a simple wall.
Yeung, Edward S.; Kuhr, Werner G.
1996-02-20
A means and method for capillary zone electrphoresis with laser-induced indirect fluorescence detection. A detector is positioned on the capillary tube of a capillary zone electrophoresis system. The detector includes a laser which generates a laser beam which is imposed upon a small portion of the capillary tube. Fluorescence of the elutant electromigrating through the capillary tube is indirectly detected and recorded.
Yeung, Edwards; Kuhr, Werner G.
1991-04-09
A means and method for capillary zone electrphoresis with laser-induced indirect fluorescence detection. A detector is positioned on the capillary tube of a capillary zone electrophoresis system. The detector includes a laser which generates a laser beam which is imposed upon a small portion of the capillary tube. Fluorescence of the elutant electromigrating through the capillary tube is indirectly detected and recorded.
Enhancing separation in short-capillary electrophoresis via pressure-driven backflow.
Tian, Miaomiao; Wang, Yujia; Mohamed, Amara Camara; Guo, Liping; Yang, Li
2015-07-01
We present a novel easy-to-operate and efficient method to improve the separation efficiency in short-capillary electrophoresis by introducing steady backflow to counterbalance electro-osmotic flow without the use of any external pressure. The backflow was easily generated by tapering the capillary end, which was achieved by heating a straight capillary and stretching it with a constant force. We investigated the net fluidic transport rate under different tip lengths and separation voltages. Good run-to-run repeatability and capillary-to-capillary reproducibility of the present method were obtained with RSD less than 1.5%, indicating the stability of the fluid transport rate in the tapered capillary, which ensures the quantification and repeatability of capillary zone electrophoresis (CZE) analysis. Enhanced separation of the tapered short capillary electrophoresis was demonstrated by CZE analyzing amino acids and positional isomers. Baseline separations were achieved in less than 60 s using a tapered capillary with the effective length of 5 cm, while no separation was achieved using a normal capillary without a tapered tip. The present study provides a promising method to use pressure-driven backflow to enhance separation efficiency in short-capillary electrophoresis, which would be of potential value in a wide application for fast analysis of complex samples. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Quantitative fine structure of capillaries in subregions of the rat subfornical organ.
Shaver, S W; Sposito, N M; Gross, P M
1990-04-01
The differentiated cytology across subregions of the rat subfornical organ (SFO) prompted our hypothesis that ultrastructural features of capillary endothelial cells would vary topographically and quantitatively within this small nucleus. We used electron microscopic and computer-based morphometric methods to assess fine structural dimensions of the capillary endothelium in four distinct subregions of the SFO from Long-Evans and homozygous Brattleboro rats. Three types of capillary were present. Type III capillaries (resembling those of endocrine glands) had an average wall thickness of 0.17 microns, 54% thinner than those of Type I and II capillaries. Pericapillary spaces around Type III capillaries measured 56 microns2, 100% larger than for Type I vessels (resembling those of skeletal muscle). Only Type III capillaries contained fenestrations (9 per microns2 of endothelial cell) and were the predominant type of capillary in central and caudal subregions of the SFO. Type I capillaries, prevalent in the transitional subregion between the central and rostral parts of the SFO, had 10 cytoplasmic vesicles per micron2 of endothelial cell area, a number not different from that of Type III capillaries but 3x the frequency found in Type II vessels. Type II capillaries (those typical of "blood-brain barrier" endothelium) had low vesicular density (3 per microns2), no fenestrations, and no pericapillary spaces. Luminal diameters and the densities of mitochondria and intercellular junctions were not different among capillary types or subregions in the SFO. Furthermore, there were no morphometric differences for any capillary dimensions between Long-Evans and Brattleboro rats.(ABSTRACT TRUNCATED AT 250 WORDS)
Measurement of Capillary Radius and Contact Angle within Porous Media.
Ravi, Saitej; Dharmarajan, Ramanathan; Moghaddam, Saeed
2015-12-01
The pore radius (i.e., capillary radius) and contact angle determine the capillary pressure generated in a porous medium. The most common method to determine these two parameters is through measurement of the capillary pressure generated by a reference liquid (i.e., a liquid with near-zero contact angle) and a test liquid. The rate of rise technique, commonly used to determine the capillary pressure, results in significant uncertainties. In this study, we utilize a recently developed technique for independently measuring the capillary pressure and permeability to determine the equivalent minimum capillary radii and contact angle of water within micropillar wick structures. In this method, the experimentally measured dryout threshold of a wick structure at different wicking lengths is fit to Darcy's law to extract the maximum capillary pressure generated by the test liquid. The equivalent minimum capillary radii of different wick geometries are determined by measuring the maximum capillary pressures generated using n-hexane as the working fluid. It is found that the equivalent minimum capillary radius is dependent on the diameter of pillars and the spacing between pillars. The equivalent capillary radii of micropillar wicks determined using the new method are found to be up to 7 times greater than the current geometry-based first-order estimates. The contact angle subtended by water at the walls of the micropillars is determined by measuring the capillary pressure generated by water within the arrays and the measured capillary radii for the different geometries. This mean contact angle of water is determined to be 54.7°.
Behavioral intervention for problem behavior in children with fragile X syndrome.
Moskowitz, Lauren J; Carr, Edward G; Durand, V Mark
2011-11-01
Parents and professionals typically report problem behavior as a significant concern for children with fragile X syndrome. In the present study, the authors explored whether behaviorally based interventions would result in a reduction in problem behavior and an improvement in quality of life for 3 children with fragile X syndrome and their families. A multiple baseline design was used to demonstrate intervention effects for specific high-priority contexts (i.e., bedtime, running errands, and toileting). A multicomponent intervention plan was developed to teach the parents and child to effectively cope with the particular context. After intervention, there were substantial improvements in problem behavior and family quality of life within the given contexts. Results of this study demonstrated the effectiveness of behavioral intervention for children with fragile X syndrome.
Lack of significant association between spina bifida and the fragile X syndrome
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schiano, C.M.; Demb, H.B.; Brown, W.T.
1995-12-04
Folic acid is involved in two common disorders associated with developmental disabilities. Spina bifida is a malformation that may be associated with mental retardation, learning disabilities, and epilepsy. Its incidence can be reduced by the ingestion of folic acid before, and at the time of, conception. The fragile X syndrome is a genetic disorder which is the most common form of inherited mental retardation. This disorder can be diagnosed by the induction of fragile sites on the X chromosome which is cultured in a medium deficient in folic acid. In several studies, folic acid was reported to alleviate some ofmore » the developmental and behavioral manifestations associated in the fragile X syndrome, while in others, it has no effect. 9 refs.« less
An Investigation of Narrative Ability in Boys with Autism and Fragile X Syndrome
Hogan-Brown, Abigail L.; Losh, Molly; Martin, Gary E.; Mueffelmann, Deborah J.
2012-01-01
Whereas pragmatic language difficulties are characteristic of both autism and Fragile X syndrome, it is unclear whether such deficits are qualitatively similar or whether certain skills are differentially affected. This study compared narrative competence in boys with autism, Fragile X syndrome, Down syndrome, and typical development. Results revealed that an interaction between diagnosis and nonverbal mental age predicted narrative microstructure (e.g., complex syntax) but not macrostructure (e.g., thematic maintenance). Correlations with FMR1-related variation were investigated in children with Fragile X syndrome. While CGG repeat length was associated with many language characteristics, nonverbal IQ appeared to mediate these relationships. These findings are an important step toward understanding narrative abilities in boys with and without the FMR1 mutation. PMID:23464607
The Pathophysiology of Fragile X (and What It Teaches Us about Synapses)
Bhakar, Asha L.; Dölen, Gül; Bear, Mark F.
2014-01-01
Fragile X is the most common known inherited cause of intellectual disability and autism, and it typically results from transcriptional silencing of FMR1 and loss of the encoded protein, FMRP (fragile X mental retardation protein). FMRP is an mRNA-binding protein that functions at many synapses to inhibit local translation stimulated by metabotropic glutamate receptors (mGluRs) 1 and 5. Recent studies on the biology of FMRP and the signaling pathways downstream of mGluR1/5 have yielded deeper insight into how synaptic protein synthesis and plasticity are regulated by experience. This new knowledge has also suggested ways that altered signaling and synaptic function can be corrected in fragile X, and human clinical trials based on this information are under way. PMID:22483044
The pathophysiology of fragile X (and what it teaches us about synapses).
Bhakar, Asha L; Dölen, Gül; Bear, Mark F
2012-01-01
Fragile X is the most common known inherited cause of intellectual disability and autism, and it typically results from transcriptional silencing of FMR1 and loss of the encoded protein, FMRP (fragile X mental retardation protein). FMRP is an mRNA-binding protein that functions at many synapses to inhibit local translation stimulated by metabotropic glutamate receptors (mGluRs) 1 and 5. Recent studies on the biology of FMRP and the signaling pathways downstream of mGluR1/5 have yielded deeper insight into how synaptic protein synthesis and plasticity are regulated by experience. This new knowledge has also suggested ways that altered signaling and synaptic function can be corrected in fragile X, and human clinical trials based on this information are under way.
Mechanism-based approaches to treating fragile X.
Dölen, Gül; Carpenter, Randall L; Ocain, Timothy D; Bear, Mark F
2010-07-01
Fragile X is the leading inherited cause of mental retardation and autism. Recent advances in our mechanistic understanding of the disease have led to the identification of the metabotropic glutamate receptor (mGluR) as a therapeutic target for the disease. These studies have revealed that core defects in multiple animal models can be corrected by down regulation of mGluR5 signaling. Although it remains to be seen if mGluR5 antagonists or related approaches will succeed in humans with fragile X, the progress in fragile X stands as a strong testament to the power of applying knowledge of basic neurobiology to understand pathophysiology in a genetically validated model of human psychiatric disease. These breakthroughs and several of the resulting drug development efforts are reviewed. (c) 2010 Elsevier Inc. All rights reserved.
Race and the Fragility of the Legal Distinction between Juveniles and Adults
Rattan, Aneeta; Levine, Cynthia S.; Dweck, Carol S.; Eberhardt, Jennifer L.
2012-01-01
Legal precedent establishes juvenile offenders as inherently less culpable than adult offenders and thus protects juveniles from the most severe of punishments. But how fragile might these protections be? In the present study, simply bringing to mind a Black (vs. White) juvenile offender led participants to view juveniles in general as significantly more similar to adults in their inherent culpability and to express more support for severe sentencing. Indeed, these differences in participants’ perceptions of this foundational legal precedent distinguishing between juveniles and adults accounted for their greater support for severe punishment. These results highlight the fragility of protections for juveniles when race is in play. Furthermore, we suggest that this fragility may have broad implications for how juveniles are seen and treated in the criminal justice system. PMID:22649496
Race and the fragility of the legal distinction between juveniles and adults.
Rattan, Aneeta; Levine, Cynthia S; Dweck, Carol S; Eberhardt, Jennifer L
2012-01-01
Legal precedent establishes juvenile offenders as inherently less culpable than adult offenders and thus protects juveniles from the most severe of punishments. But how fragile might these protections be? In the present study, simply bringing to mind a Black (vs. White) juvenile offender led participants to view juveniles in general as significantly more similar to adults in their inherent culpability and to express more support for severe sentencing. Indeed, these differences in participants' perceptions of this foundational legal precedent distinguishing between juveniles and adults accounted for their greater support for severe punishment. These results highlight the fragility of protections for juveniles when race is in play. Furthermore, we suggest that this fragility may have broad implications for how juveniles are seen and treated in the criminal justice system.
Ion guiding in macro-size insulating capillaries: straight, tapered, and curved shapes
NASA Astrophysics Data System (ADS)
Kojima, Takao M.
2018-02-01
When keV energy ions are injected into a tilted insulating capillary, a certain fraction of the injected ions are transported through the tilt angle of the capillary. This ion guiding phenomenon is considered to be caused by a self-organizing charge distribution, where the inner wall of the capillary becomes charged by initial incoming ions. The charge distribution, which is formed, can guide following ions toward the exit of the capillary. Since the initial discovery of this effect, studies of ion guiding by insulating capillaries have been extended to various materials, and different sizes and shapes of capillaries. In recent years, some investigations of the guiding effect of macro-size curved capillaries have also been reported. In this review, relevant studies in a history of ion guiding in curved capillaries are discussed and future directions in this field are considered.
High-speed video capillaroscopy method for imaging and evaluation of moving red blood cells
NASA Astrophysics Data System (ADS)
Gurov, Igor; Volkov, Mikhail; Margaryants, Nikita; Pimenov, Aleksei; Potemkin, Andrey
2018-05-01
The video capillaroscopy system with high image recording rate to resolve moving red blood cells with velocity up to 5 mm/s into a capillary is considered. Proposed procedures of the recorded video sequence processing allow evaluating spatial capillary area, capillary diameter and central line with high accuracy and reliability independently on properties of individual capillary. Two-dimensional inter frame procedure is applied to find lateral shift of neighbor images in the blood flow area with moving red blood cells and to measure directly the blood flow velocity along a capillary central line. The developed method opens new opportunities for biomedical diagnostics, particularly, due to long-time continuous monitoring of red blood cells velocity into capillary. Spatio-temporal representation of capillary blood flow is considered. Experimental results of direct measurement of blood flow velocity into separate capillary as well as capillary net are presented and discussed.
Automated Parallel Capillary Electrophoretic System
Li, Qingbo; Kane, Thomas E.; Liu, Changsheng; Sonnenschein, Bernard; Sharer, Michael V.; Kernan, John R.
2000-02-22
An automated electrophoretic system is disclosed. The system employs a capillary cartridge having a plurality of capillary tubes. The cartridge has a first array of capillary ends projecting from one side of a plate. The first array of capillary ends are spaced apart in substantially the same manner as the wells of a microtitre tray of standard size. This allows one to simultaneously perform capillary electrophoresis on samples present in each of the wells of the tray. The system includes a stacked, dual carousel arrangement to eliminate cross-contamination resulting from reuse of the same buffer tray on consecutive executions from electrophoresis. The system also has a gel delivery module containing a gel syringe/a stepper motor or a high pressure chamber with a pump to quickly and uniformly deliver gel through the capillary tubes. The system further includes a multi-wavelength beam generator to generate a laser beam which produces a beam with a wide range of wavelengths. An off-line capillary reconditioner thoroughly cleans a capillary cartridge to enable simultaneous execution of electrophoresis with another capillary cartridge. The streamlined nature of the off-line capillary reconditioner offers the advantage of increased system throughput with a minimal increase in system cost.
Fluid Delivery System For Capillary Electrophoretic Applications.
Li, Qingbo; Liu, Changsheng; Kane, Thomas E.; Kernan, John R.; Sonnenschein, Bernard; Sharer, Michael V.
2002-04-23
An automated electrophoretic system is disclosed. The system employs a capillary cartridge having a plurality of capillary tubes. The cartridge has a first array of capillary ends projecting from one side of a plate. The first array of capillary ends are spaced apart in substantially the same manner as the wells of a microtitre tray of standard size. This allows one to simultaneously perform capillary electrophoresis on samples present in each of the wells of the tray. The system includes a stacked, dual carrousel arrangement to eliminate cross-contamination resulting from reuse of the same buffer tray on consecutive executions from electrophoresis. The system also has a gel delivery module containing a gel syringe/a stepper motor or a high pressure chamber with a pump to quickly and uniformly deliver gel through the capillary tubes. The system further includes a multi-wavelength beam generator to generate a laser beam which produces a beam with a wide range of wavelengths. An off-line capillary reconditioner thoroughly cleans a capillary cartridge to enable simultaneous execution of electrophoresis with another capillary cartridge. The streamlined nature of the off-line capillary reconditioner offers the advantage of increased system throughput with a minimal increase in system cost.
Intention tremor, parkinsonism, and generalized brain atrophy in male carriers of fragile X.
Hagerman, R J; Leehey, M; Heinrichs, W; Tassone, F; Wilson, R; Hills, J; Grigsby, J; Gage, B; Hagerman, P J
2001-07-10
The authors report five elderly men with the fragile X premutation who had a progressive action tremor associated with executive function deficits and generalized brain atrophy. These individuals had elevated fragile X mental retardation 1 gene (FMR1) messenger RNA and normal or borderline levels of FMR1 protein. The authors propose that elevations of FMR1 messenger RNA may be causative for a neurodegenerative syndrome in a subgroup of elderly men with the FMR1 premutation.
Agricultural Fragility Estimates Subjected to Volcanic Ash Fall Hazards
NASA Astrophysics Data System (ADS)
Ham, H. J.; Lee, S.; Choi, S. H.; Yun, W. S.
2015-12-01
Agricultural Fragility Estimates Subjected to Volcanic Ash Fall Hazards Hee Jung Ham1, Seung-Hun Choi1, Woo-Seok Yun1, Sungsu Lee2 1Department of Architectural Engineering, Kangwon National University, Korea 2Division of Civil Engineering, Chungbuk National University, Korea ABSTRACT In this study, fragility functions are developed to estimate expected volcanic ash damages of the agricultural sector in Korea. The fragility functions are derived from two approaches: 1) empirical approach based on field observations of impacts to agriculture from the 2006 eruption of Merapi volcano in Indonesia and 2) the FOSM (first-order second-moment) analytical approach based on distribution and thickness of volcanic ash observed from the 1980 eruption of Mt. Saint Helens and agricultural facility specifications in Korea. Fragility function to each agricultural commodity class is presented by a cumulative distribution function of the generalized extreme value distribution. Different functions are developed to estimate production losses from outdoor and greenhouse farming. Seasonal climate influences vulnerability of each agricultural crop and is found to be a crucial component in determining fragility of agricultural commodities to an ash fall. In the study, the seasonality coefficient is established as a multiplier of fragility function to consider the seasonal vulnerability. Yields of the different agricultural commodities are obtained from Korean Statistical Information Service to create a baseline for future agricultural volcanic loss estimation. Numerically simulated examples of scenario ash fall events at Mt. Baekdu volcano are utilized to illustrate the application of the developed fragility functions. Acknowledgements This research was supported by a grant 'Development of Advanced Volcanic Disaster Response System considering Potential Volcanic Risk around Korea' [MPSS-NH-2015-81] from the Natural Hazard Mitigation Research Group, Ministry of Public Safety and Security of Korea. References Nimlos, T. J. and Hans, Z., The Distribution and Thickness of Volcanic Ash in Montana, Northwest Science, Vol. 56, No. 3, 1982. Wilson, T., Kaye, G., Stewart, C., and Cole, J., Impacts of the 2006 Eruption of Merapi Volcano, Indonesia, on Agriculture and Infrastructure, GNS Science Report, 2007.
Early changes in fiber profile and capillary density in long-term stimulated muscles.
Hudlická, O; Dodd, L; Renkin, E M; Gray, S D
1982-10-01
Predominantly fast skeletal muscles of rabbits [tibialis anterior (TA), extensor digitorum longus (EDL)] were stimulated at a frequency naturally occurring in nerves to slow muscles (10 Hz continuously) for 8 h/day for 2--4 days. Such stimulation is known to convert all glycolytic fibers to oxidative and to increase capillary density. Our aim was to study early stages of conversion to investigate the factors responsible for the changes. Staining of quick-frozen sections for myosin ATPase, succinic dehydrogenase, and alkaline phosphatase was used to study the distribution of different fiber types and to measure fiber cross-sectional areas, capillaries per square millimeter, and capillary-to-fiber ratios in each fiber category. TA but not EDL showed conversion of fast glycolytic to fast oxidative fibers after 2 days, more after 4 days of stimulation. In both muscles, the largest fast glycolytic fibers were diminished in number after stimulation. There was significant increase in total capillaries per square millimeter after 4 days and some increase after 2 days of stimulation. The increase in capillaries per square millimeter exceeded the increase in the number of fibers per square millimeter, and since there was no change in mean fiber area, the increase is attributed to capillary growth. In EDL, there was an increase in the number of capillaries supplying both fast glycolytic and fast oxidative fibers, suggesting that capillary growth precedes fiber type conversion. In TA, the number of capillaries supplying fast oxidative fibers was increased but that to fast glycolytic fibers, was not. This is consistent with capillary growth simultaneous with or following fiber conversion. In both TA and EDL the number of capillaries perfused after contraction was higher in stimulated muscles, suggesting that increased capillary flow contributed to capillary growth.
Quantitative analysis of nailfold capillary morphology in patients with fibromyalgia
Choi, Dug-Hyun
2015-01-01
Background/Aims Nailfold capillaroscopy (NFC) has been used to examine morphological and functional microcirculation changes in connective tissue diseases. It has been demonstrated that NFC patterns reflect abnormal microvascular dynamics, which may play a role in fibromyalgia (FM) syndrome. The aim of this study was to determine NFC patterns in FM, and their association with clinical features of FM. Methods A total of 67 patients with FM, and 30 age- and sex-matched healthy controls, were included. Nailfold capillary patterns were quantitatively analyzed using computerized NFC. The parameters of interest were as follows: number of capillaries within the central 3 mm, deletion score, apical limb width, capillary width, and capillary dimension. Capillary dimension was determined by calculating the number of capillaries using the Adobe Photoshop version 7.0. Results FM patients had a lower number of capillaries and higher deletion scores on NFC compared to healthy controls (17.3 ± 1.7 vs. 21.8 ± 2.9, p < 0.05; 2.2 ± 0.9 vs. 0.7 ± 0.6, p < 0.05, respectively). Both apical limb width (µm) and capillary width (µm) were significantly decreased in FM patients (1.1 ± 0.2 vs. 3.7 ± 0.6; 5.4 ± 0.5 vs. 7.5 ± 1.4, respectively), indicating that FM patients have abnormally decreased digital capillary diameter and density. Interestingly, there was no difference in capillary dimension between the two groups, suggesting that the length or tortuosity of capillaries in FM patients is increased to compensate for diminished microcirculation. Conclusions FM patients had altered capillary density and diameter in the digits. Diminished microcirculation on NFC may alter capillary density and increase tortuosity. PMID:26161020
Castello, Lucía V; Galetto, Leonardo
2013-01-01
Tillandsia capillaris Ruiz & Pav., which belongs to the subgenus Diaphoranthema is distributed in Ecuador, Peru, Bolivia, northern and central Argentina, and Chile, and includes forms that are difficult to circumscribe, thus considered to form a complex. The entities of this complex are predominantly small-sized epiphytes, adapted to xeric environments. The most widely used classification defines 5 forms for this complex based on few morphological reproductive traits: Tillandsia capillaris Ruiz & Pav. f. capillaris, Tillandsia capillaris f. incana (Mez) L.B. Sm., Tillandsia capillaris f. cordobensis (Hieron.) L.B. Sm., Tillandsia capillaris f. hieronymi (Mez) L.B. Sm. and Tillandsia capillaris f. virescens (Ruiz & Pav.) L.B. Sm. In this study, 35 floral and vegetative characters were analyzed with a multivariate approach in order to assess and discuss different proposals for classification of the Tillandsia capillaris complex, which presents morphotypes that co-occur in central and northern Argentina. To accomplish this, data of quantitative and categorical morphological characters of flowers and leaves were collected from herbarium specimens and field collections and were analyzed with statistical multivariate techniques. The results suggest that the last classification for the complex seems more comprehensive and three taxa were delimited: Tillandsia capillaris (=Tillandsia capillaris f. incana-hieronymi), Tillandsia virescens s. str. (=Tillandsia capillaris f. cordobensis) and Tillandsia virescens s. l. (=Tillandsia capillaris f. virescens). While Tillandsia capillaris and Tillandsia virescens s. str. co-occur, Tillandsia virescens s. l. is restricted to altitudes above 2000 m in Argentina. Characters previously used for taxa delimitation showed continuous variation and therefore were not useful. New diagnostic characters are proposed and a key is provided for delimiting these three taxa within the complex.
Castello, Lucía V.; Galetto, Leonardo
2013-01-01
Abstract Tillandsia capillaris Ruiz & Pav., which belongs to the subgenus Diaphoranthema is distributed in Ecuador, Peru, Bolivia, northern and central Argentina, and Chile, and includes forms that are difficult to circumscribe, thus considered to form a complex. The entities of this complex are predominantly small-sized epiphytes, adapted to xeric environments. The most widely used classification defines 5 forms for this complex based on few morphological reproductive traits: Tillandsia capillaris Ruiz & Pav. f. capillaris, Tillandsia capillaris f. incana (Mez) L.B. Sm., Tillandsia capillaris f. cordobensis (Hieron.) L.B. Sm., Tillandsia capillaris f. hieronymi (Mez) L.B. Sm. and Tillandsia capillaris f. virescens (Ruiz & Pav.) L.B. Sm. In this study, 35 floral and vegetative characters were analyzed with a multivariate approach in order to assess and discuss different proposals for classification of the Tillandsia capillaris complex, which presents morphotypes that co-occur in central and northern Argentina. To accomplish this, data of quantitative and categorical morphological characters of flowers and leaves were collected from herbarium specimens and field collections and were analyzed with statistical multivariate techniques. The results suggest that the last classification for the complex seems more comprehensive and three taxa were delimited: Tillandsia capillaris (=Tillandsia capillaris f. incana-hieronymi), Tillandsia virescens s. str. (=Tillandsia capillaris f. cordobensis) and Tillandsia virescens s. l. (=Tillandsia capillaris f. virescens). While Tillandsia capillaris and Tillandsia virescens s. str. co-occur, Tillandsia virescens s. l. is restricted to altitudes above 2000 m in Argentina. Characters previously used for taxa delimitation showed continuous variation and therefore were not useful. New diagnostic characters are proposed and a key is provided for delimiting these three taxa within the complex. PMID:23805053
Capillary Structures for Exploration Life Support (Capillary Structures)
2017-07-10
iss052e013146 (July 10, 2017) --- Astronaut Jack Fischer is photographed during setup of hardware for the Capillary Structures for Exploration Life Support (Capillary Structures) two sorbent demonstrations. The Capillary Structures for Exploration Life Support (Capillary Structures) investigation studies a new method using structures of specific shapes to manage fluid and gas mixtures. The investigation studies water recycling and carbon dioxide removal, benefiting future efforts to design lightweight, more reliable life support systems for future space missions.
Learning about Fragile X Syndrome
... Physical problems that have been seen include eye, orthopedic, heart and skin problems. Girls who have the ... to their sons. Top of page NHGRI Clinical Research on Fragile X Syndrome Currently, NHGRI is not ...
... POI. For example, women Fragile X syndrome or Turner syndrome are at higher risk. Certain diseases, such as ... Genetic disorders such as Fragile X syndrome and Turner syndrome A low number of follicles Autoimmune diseases, including ...
NASA Astrophysics Data System (ADS)
Palakurthi, Nikhil Kumar; Ghia, Urmila; Comer, Ken
2013-11-01
Capillary penetration of liquid through fibrous porous media is important in many applications such as printing, drug delivery patches, sanitary wipes, and performance fabrics. Historically, capillary transport (with a distinct liquid propagating front) in porous media is modeled using capillary-bundle theory. However, it is not clear if the capillary model (Washburn equation) describes the fluid transport in porous media accurately, as it assumes uniformity of pore sizes in the porous medium. The present work investigates the limitations of the applicability of the capillary model by studying liquid penetration through virtual fibrous media with uniform and non-uniform pore-sizes. For the non-uniform-pore fibrous medium, the effective capillary radius of the fibrous medium was estimated from the pore-size distribution curve. Liquid penetration into the 3D virtual fibrous medium at micro-scale was simulated using OpenFOAM, and the numerical results were compared with the Washburn-equation capillary-model predictions. Preliminary results show that the Washburn equation over-predicts the height rise in the early stages (purely inertial and visco-inertial stages) of capillary transport.
Dickerson, Jane A.; Ramsay, Lauren M.; Dada, Oluwatosin O.; Cermak, Nathan
2011-01-01
Capillary isoelectric focusing and capillary zone electrophoresis are coupled with laser-induced fluorescence detection to create an ultrasensitive two-dimensional separation method for proteins. In this method, two capillaries are joined through a buffer filled interface. Separate power supplies control the potential at the injection end of the first capillary and at the interface; the detector is held at ground potential. Proteins are labeled with the fluorogenic reagent Chromeo P503, which preserves the isoelectric point of the labeled protein. The labeled proteins were mixed with ampholytes and injected into the first dimension capillary. A focusing step was performed with the injection end of the capillary at high pH and the interface at low pH. To mobilize components, the interface was filled with a high pH buffer, which was compatible with the second dimension separation. A fraction was transferred to the second dimension capillary for separation. The process of fraction transfer and second dimension separation was repeated two dozen times. The separation produced a spot capacity of 125. PMID:20603830
Capillarics: pre-programmed, self-powered microfluidic circuits built from capillary elements.
Safavieh, Roozbeh; Juncker, David
2013-11-07
Microfluidic capillary systems employ surface tension effects to manipulate liquids, and are thus self-powered and self-regulated as liquid handling is structurally and chemically encoded in microscale conduits. However, capillary systems have been limited to perform simple fluidic operations. Here, we introduce complex capillary flow circuits that encode sequential flow of multiple liquids with distinct flow rates and flow reversal. We first introduce two novel microfluidic capillary elements including (i) retention burst valves and (ii) robust low aspect ratio trigger valves. These elements are combined with flow resistors, capillary retention valves, capillary pumps, and open and closed reservoirs to build a capillary circuit that, following sample addition, autonomously delivers a defined sequence of multiple chemicals according to a preprogrammed and predetermined flow rate and time. Such a circuit was used to measure the concentration of C-reactive protein. This work illustrates that as in electronics, complex capillary circuits may be built by combining simple capillary elements. We define such circuits as "capillarics", and introduce symbolic representations. We believe that more complex circuits will become possible by expanding the library of building elements and formulating abstract design rules.
Particle sizer and DNA sequencer
Olivares, Jose A.; Stark, Peter C.
2005-09-13
An electrophoretic device separates and detects particles such as DNA fragments, proteins, and the like. The device has a capillary which is coated with a coating with a low refractive index such as Teflon.RTM. AF. A sample of particles is fluorescently labeled and injected into the capillary. The capillary is filled with an electrolyte buffer solution. An electrical field is applied across the capillary causing the particles to migrate from a first end of the capillary to a second end of the capillary. A detector light beam is then scanned along the length of the capillary to detect the location of the separated particles. The device is amenable to a high throughput system by providing additional capillaries. The device can also be used to determine the actual size of the particles and for DNA sequencing.
Fragile X-Associated Primary Ovarian Insufficiency (FXPOI)
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Fragile X syndrome: from molecular genetics to therapy.
D'Hulst, C; Kooy, R F
2009-09-01
Fragile X syndrome, the main cause of inherited mental retardation, is caused by transcriptional silencing of the fragile X mental retardation gene, FMR1. Absence of the associated protein FMRP leads to the dysregulation of many genes creating a phenotype of ADHD, anxiety, epilepsy and autism. The core aim of this review is to summarise two decades of molecular research leading to the characterisation of cellular and molecular pathways involved in the pathology of this disease and as a consequence to the identification of two new promising targets for rational therapy of fragile X syndrome, namely the group 1 metabotrope glutamate receptors (Gp1 mGluRs) and the gamma-amino butyric acid A receptors (GABA(A)Rs). As no current clinical treatments are directed specifically at the underlying neuronal defect due to absence of FMRP, this might open new powerful therapeutic strategies.
Targeted pharmacological treatment of autism spectrum disorders: fragile X and Rett syndromes
Wang, Hansen; Pati, Sandipan; Pozzo-Miller, Lucas; Doering, Laurie C.
2015-01-01
Autism spectrum disorders (ASDs) are genetically and clinically heterogeneous and lack effective medications to treat their core symptoms. Studies of syndromic ASDs caused by single gene mutations have provided insights into the pathophysiology of autism. Fragile X and Rett syndromes belong to the syndromic ASDs in which preclinical studies have identified rational targets for drug therapies focused on correcting underlying neural dysfunction. These preclinical discoveries are increasingly translating into exciting human clinical trials. Since there are significant molecular and neurobiological overlaps among ASDs, targeted treatments developed for fragile X and Rett syndromes may be helpful for autism of different etiologies. Here, we review the targeted pharmacological treatment of fragile X and Rett syndromes and discuss related issues in both preclinical studies and clinical trials of potential therapies for the diseases. PMID:25767435
Clinical, molecular, and pharmacological aspects of FMR1 related disorders.
Pugin, A; Faundes, V; Santa María, L; Curotto, B; Aliaga, S; Salas, I; Soto, P; Bravo, P; Peña, M I; Alliende, M A
2017-05-01
Fragile X syndrome, the most common inherited cause of intellectual disability, is associated with a broad spectrum of disorders across different generations of a single family. This study reviews the clinical manifestations of fragile X-associated disorders as well as the spectrum of mutations of the fragile X mental retardation 1 gene (FMR1) and the neurobiology of the fragile X mental retardation protein (FMRP), and also provides an overview of the potential therapeutic targets and genetic counselling. This disorder is caused by expansion of the CGG repeat (>200 repeats) in the 5 prime untranslated region of FMR1, resulting in a deficit or absence of FMRP. FMRP is an RNA-binding protein that regulates the translation of several genes that are important in synaptic plasticity and dendritic maturation. It is believed that CGG repeat expansions in the premutation range (55 to 200 repeats) elicit an increase in mRNA levels of FMR1, which may cause neuronal toxicity. These changes manifest clinically as developmental problems such as autism and learning disabilities as well as neurodegenerative diseases including fragile X-associated tremor/ataxia syndrome (FXTAS). Advances in identifying the molecular basis of fragile X syndrome may help us understand the causes of neuropsychiatric disorders, and they will probably contribute to development of new and specific treatments. Copyright © 2014 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.
Lan, Hong; Chen, Chun-Li; Miao, Yin; Yu, Chang-Xiu; Guo, Wen-Wu; Xu, Qiang; Deng, Xiu-Xin
2016-01-01
Citrus sinensis chromosomes present a morphological differentiation of bands after staining by the fluorochromes CMA and DAPI, but there is still little information on its chromosomal characteristics. In this study, the chromosomes in ‘Valencia’ C. sinensis were analyzed by fluorescence in situ hybridization (FISH) using telomere DNA and the 45S rDNA gene as probes combining CMA/DAPI staining, which showed that there were two fragile sites in sweet orange chromosomes co-localizing at distended 45S rDNA regions, one proximally locating on B-type chromosome and the other subterminally locating on D-type chromosome. While the chromosomal CMA banding and 45S rDNA FISH mapping in the doubled haploid line of ‘Valencia’ C. sinensis indicated six 45S rDNA regions, four were identified as fragile sites as doubled comparing its parental line, which confirmed the cytological heterozygosity and chromosomal heteromorphisms in sweet orange. Furthermore, Ag-NOR identified two distended 45S rDNA regions to be active nucleolar organizing regions (NORs) in diploid ‘Valencia’ C. sinensis. The occurrence of quadrivalent in meiosis of pollen mother cells (PMCs) in ‘Valencia’ sweet orange further confirmed it was a chromosomal reciprocal translocation line. We speculated this chromosome translocation was probably related to fragile sites. Our data provide insights into the chromosomal characteristics of the fragile sites in ‘Valencia’ sweet orange and are expected to facilitate the further investigation of the possible functions of fragile sites. PMID:26977938
Lan, Hong; Chen, Chun-Li; Miao, Yin; Yu, Chang-Xiu; Guo, Wen-Wu; Xu, Qiang; Deng, Xiu-Xin
2016-01-01
Citrus sinensis chromosomes present a morphological differentiation of bands after staining by the fluorochromes CMA and DAPI, but there is still little information on its chromosomal characteristics. In this study, the chromosomes in 'Valencia' C. sinensis were analyzed by fluorescence in situ hybridization (FISH) using telomere DNA and the 45S rDNA gene as probes combining CMA/DAPI staining, which showed that there were two fragile sites in sweet orange chromosomes co-localizing at distended 45S rDNA regions, one proximally locating on B-type chromosome and the other subterminally locating on D-type chromosome. While the chromosomal CMA banding and 45S rDNA FISH mapping in the doubled haploid line of 'Valencia' C. sinensis indicated six 45S rDNA regions, four were identified as fragile sites as doubled comparing its parental line, which confirmed the cytological heterozygosity and chromosomal heteromorphisms in sweet orange. Furthermore, Ag-NOR identified two distended 45S rDNA regions to be active nucleolar organizing regions (NORs) in diploid 'Valencia' C. sinensis. The occurrence of quadrivalent in meiosis of pollen mother cells (PMCs) in 'Valencia' sweet orange further confirmed it was a chromosomal reciprocal translocation line. We speculated this chromosome translocation was probably related to fragile sites. Our data provide insights into the chromosomal characteristics of the fragile sites in 'Valencia' sweet orange and are expected to facilitate the further investigation of the possible functions of fragile sites.
Multiple capillary biochemical analyzer
Dovichi, N.J.; Zhang, J.Z.
1995-08-08
A multiple capillary analyzer allows detection of light from multiple capillaries with a reduced number of interfaces through which light must pass in detecting light emitted from a sample being analyzed, using a modified sheath flow cuvette. A linear or rectangular array of capillaries is introduced into a rectangular flow chamber. Sheath fluid draws individual sample streams through the cuvette. The capillaries are closely and evenly spaced and held by a transparent retainer in a fixed position in relation to an optical detection system. Collimated sample excitation radiation is applied simultaneously across the ends of the capillaries in the retainer. Light emitted from the excited sample is detected by the optical detection system. The retainer is provided by a transparent chamber having inward slanting end walls. The capillaries are wedged into the chamber. One sideways dimension of the chamber is equal to the diameter of the capillaries and one end to end dimension varies from, at the top of the chamber, slightly greater than the sum of the diameters of the capillaries to, at the bottom of the chamber, slightly smaller than the sum of the diameters of the capillaries. The optical system utilizes optic fibers to deliver light to individual photodetectors, one for each capillary tube. A filter or wavelength division demultiplexer may be used for isolating fluorescence at particular bands. 21 figs.
Progression of Diabetic Capillary Occlusion: A Model
Gens, John Scott; Glazier, James A.; Burns, Stephen A.; Gast, Thomas J.
2016-01-01
An explanatory computational model is developed of the contiguous areas of retinal capillary loss which play a large role in diabetic maculapathy and diabetic retinal neovascularization. Strictly random leukocyte mediated capillary occlusion cannot explain the occurrence of large contiguous areas of retinal ischemia. Therefore occlusion of an individual capillary must increase the probability of occlusion of surrounding capillaries. A retinal perifoveal vascular sector as well as a peripheral retinal capillary network and a deleted hexagonal capillary network are modelled using Compucell3D. The perifoveal modelling produces a pattern of spreading capillary loss with associated macular edema. In the peripheral network, spreading ischemia results from the progressive loss of the ladder capillaries which connect peripheral arterioles and venules. System blood flow was elevated in the macular model before a later reduction in flow in cases with progression of capillary occlusions. Simulations differing only in initial vascular network structures but with identical dynamics for oxygen, growth factors and vascular occlusions, replicate key clinical observations of ischemia and macular edema in the posterior pole and ischemia in the retinal periphery. The simulation results also seem consistent with quantitative data on macular blood flow and qualitative data on venous oxygenation. One computational model applied to distinct capillary networks in different retinal regions yielded results comparable to clinical observations in those regions. PMID:27300722
Multiple capillary biochemical analyzer
Dovichi, Norman J.; Zhang, Jian Z.
1995-01-01
A multiple capillary analyzer allows detection of light from multiple capillaries with a reduced number of interfaces through which light must pass in detecting light emitted from a sample being analyzed, using a modified sheath flow cuvette. A linear or rectangular array of capillaries is introduced into a rectangular flow chamber. Sheath fluid draws individual sample streams through the cuvette. The capillaries are closely and evenly spaced and held by a transparent retainer in a fixed position in relation to an optical detection system. Collimated sample excitation radiation is applied simultaneously across the ends of the capillaries in the retainer. Light emitted from the excited sample is detected by the optical detection system. The retainer is provided by a transparent chamber having inward slanting end walls. The capillaries are wedged into the chamber. One sideways dimension of the chamber is equal to the diameter of the capillaries and one end to end dimension varies from, at the top of the chamber, slightly greater than the sum of the diameters of the capillaries to, at the bottom of the chamber, slightly smaller than the sum of the diameters of the capillaries. The optical system utilizes optic fibres to deliver light to individual photodetectors, one for each capillary tube. A filter or wavelength division demultiplexer may be used for isolating fluorescence at particular bands.
Luna-Ramos, Gissel Karelly; Pedraza-Zárate, Miguel Ángel; Franco-Álvarez, Nubia; González-Velázquez, Felipe
2016-01-01
The elderly patients with fragility show different physiological changes, so they are given polymeric diets to maintain and/or alter their nutritional status. The aim of this paper is to demonstrate the effect of changing a standard polymeric diet and a standard diet on nutritional status in elderly patients with fragility. Clinical randomized controlled trial in 23 elderly patients, 70 years of age or older, with fragility, hospitalized in a Internal Medicine Unity in a period from July to December 2014. Nutritional status was determined through Minimum Nutritional Consulting (MNA) and body mass index (BMI). Descriptive statistics, Chi square, Student t test and McNemar. In the G1: 12 patients were in the G2 and 11, a positive change was observed in the nutritional status G1 initially being 14.00 (malnutrition) and end 22.75 (risk of malnutrition). According to BMI (kg/m2) was evident at the beginning 25 % of patients (3) with mild malnutrition, but the final results show figures with a zero percentage of malnourished patients. The use of standard polymeric diet increases body weight, BMI and nutritional status in elderly patients with fragility.
A Comparison of Pragmatic Language in Boys with Autism and Fragile X Syndrome
Klusek, Jessica; Martin, Gary E.; Losh, Molly
2014-01-01
Purpose Impaired pragmatic language (i.e., language use for social interaction) is a hallmark feature of both autism spectrum disorder (ASD) and fragile X syndrome (FXS), the most common known monogenic disorder associated with ASD. However, few cross-population comparisons of ASD and FXS have been conducted, and it is unclear whether pragmatic language profiles in these conditions overlap. Method This study used semi-naturalistic and standardized assessment methods to characterize pragmatic language abilities of 29 school-aged boys with idiopathic ASD, 38 with FXS and comorbid ASD, 16 with FXS without ASD, 20 with Down syndrome and 20 with typical development. Results Similar severity of pragmatic language deficits was observed in both of the groups with ASD (idiopathic and fragile X-associated). ASD comorbidity had a detrimental effect on the pragmatic language skills of boys with FXS. Some different patterns emerged across the two pragmatic assessment tools, with more robust group differences observed in pragmatics assessed in a semi-naturalistic conversational context. Conclusions These findings have implications for pragmatic language assessment and intervention, as well as for understanding the potential role of the fragile X gene, Fragile X Mental Retardation-1, in the pragmatic language phenotype of ASD. PMID:24686468
Bogoch, Earl R.; Snowden, Elizabeth
2008-01-01
Objective The orthopedic community is in a unique position to initiate and provide osteoporosis care in fragility fracture patients to prevent future hip fractures in a high-risk population. The attitudes and intentions of Canadian orthopedic surgeons in the domain of osteoporosis care are unknown. Our objective was to identify current attitudes and osteoporosis management practices and to determine their overall willingness to participate in osteoporosis care for fragility fracture patients. Methods A real-time interactive polling session was conducted at the 58th Annual Meeting of the Canadian Orthopaedic Association. Results Of the orthopedic surgeons who responded, 90.4% agreed that the current emphasis on osteoporosis in orthopedic practice is appropriate; 85.2% of surgeons indicated that they currently refer or personally investigate for osteoporosis, or both, in fragility fracture patients. Conclusion Most of the Canadian orthopedic surgeons sampled consider themselves to be currently engaged or ready to engage in osteoporosis care for fragility fracture patients. Focus should now shift from education and persuasion to program support through provision of resources and system modification that will enable Canadian orthopedic surgeons to effectively manage osteoporosis in their fracture patients. PMID:18248700
Autism Is Associated with the Fragile-X Syndrome.
ERIC Educational Resources Information Center
Brown, W. Ted.; And Others
1982-01-01
The authors describe their methods for establishing the presence or absence of the fragile-X chromosome and discuss some of the clinical implications of their findings in relation to the clinical diagnosis of autism. (SW)
Genetics Home Reference: fragile XE syndrome
... are so mild that the individuals function normally. Learning disabilities are the most common sign of impaired cognitive function in people with fragile XE syndrome . The learning disabilities are likely a result of communication and behavioral ...
Hall, Stephen H.
1996-01-01
The present invention is a reference half-cell electrode wherein intermingling of test fluid with reference fluid does not affect the performance of the reference half-cell over a long time. This intermingling reference half-cell may be used as a single or double junction submersible or surface reference electrode. The intermingling reference half-cell relies on a capillary tube having a first end open to reference fluid and a second end open to test fluid wherein the small diameter of the capillary tube limits free motion of fluid within the capillary to diffusion. The electrode is placed near the first end of the capillary in contact with the reference fluid. The method of operation of the present invention begins with filling the capillary tube with a reference solution. After closing the first end of the capillary, the capillary tube may be fully submerged or partially submerged with the second open end inserted into test fluid. Since the electrode is placed near the first end of the capillary, and since the test fluid may intermingle with the reference fluid through the second open end only by diffusion, this intermingling capillary reference half-cell provides a stable voltage potential for long time periods.
Hall, S.H.
1996-02-13
The present invention is a reference half-cell electrode wherein intermingling of test fluid with reference fluid does not affect the performance of the reference half-cell over a long time. This intermingling reference half-cell may be used as a single or double junction submersible or surface reference electrode. The intermingling reference half-cell relies on a capillary tube having a first end open to reference fluid and a second end open to test fluid wherein the small diameter of the capillary tube limits free motion of fluid within the capillary to diffusion. The electrode is placed near the first end of the capillary in contact with the reference fluid. The method of operation of the present invention begins with filling the capillary tube with a reference solution. After closing the first end of the capillary, the capillary tube may be fully submerged or partially submerged with the second open end inserted into test fluid. Since the electrode is placed near the first end of the capillary, and since the test fluid may intermingle with the reference fluid through the second open end only by diffusion, this intermingling capillary reference half-cell provides a stable voltage potential for long time periods. 11 figs.
Electrphoretic Sample Excitation Light Assembly.
Li, Qingbo; Liu, Changsheng
2002-04-02
An automated electrophoretic system is disclosed. The system employs a capillary cartridge having a plurality of capillary tubes. The cartridge has a first array of capillary ends projecting from one side of a plate. The first array of capillary ends are spaced apart in substantially the same manner as the wells of a microtitre tray of standard size. This allows one to simultaneously perform capillary electrophoresis on samples present in each of the wells of the tray. The system includes a stacked, dual carrousel arrangement to eliminate cross-contamination resulting from reuse of the same buffer tray on consecutive executions from electrophoresis. The system also has a gel delivery module containing a gel syringe/a stepper motor or a high pressure chamber with a pump to quickly and uniformly deliver gel through the capillary tubes. The system further includes a multi-wavelength beam generator to generate a laser beam which produces a beam with a wide range of wavelengths. An off-line capillary reconditioner thoroughly cleans a capillary cartridge to enable simultaneous execution of electrophoresis with another capillary cartridge. The streamlined nature of the off-line capillary reconditioner offers the advantage of increased system throughput with a minimal increase in system cost.
Motorized Positioning Apparatus Having Coaxial Carrousels.
Li, Qingbo; Kane, Thomas E.; Liu, Changsheng; Sonnenschein, Bernard; Sharer, Michael V.; Kernan, John R.
2002-04-02
An automated electrophoretic system is disclosed. The system employs a capillary cartridge having a plurality of capillary tubes. The cartridge has a first array of capillary ends projecting from one side of a plate. The first array of capillary ends are spaced apart in substantially the same manner as the wells of a microtitre tray of standard size. This allows one to simultaneously perform capillary electrophoresis on samples present in each of the wells of the tray. The system includes a stacked, dual carrousel arrangement to eliminate cross-contamination resulting from reuse of the same buffer tray on consecutive executions from electrophoresis. The system also has a gel delivery module containing a gel syringe/a stepper motor or a high pressure chamber with a pump to quickly and uniformly deliver gel through the capillary tubes. The system further includes a multi-wavelength beam generator to generate a laser beam which produces a beam with a wide range of wavelengths. An off-line capillary reconditioner thoroughly cleans a capillary cartridge to enable simultaneous execution of electrophoresis with another capillary cartridge. The streamlined nature of the off-line capillary reconditioner offers the advantage of increased system throughput with a minimal increase in system cost.
Li, Qiang; Pu, Xiaoyun
2013-07-20
A method for measuring the refractive index (RI) of a small volume of liquid and a capillary wall is presented in this paper. A transparent capillary filled with liquid is used as a cylindrical positive lens; subsequently, the focal length of the lens is derived through the base of paraxial approximation, which is recorded as a function of the RIs of the liquid and capillary wall. With the RI of a capillary wall known, the RI of the liquid can be obtained by measuring the focal length of the lens, which is characterized by a microquantity liquid, spatial resolution, and easy operation. The RI of the capillary wall can be calculated without ruining the capillary if the capillary is filled with a standard liquid (RI is known), the deviation of which is less than 0.003 RIU. The factors affecting accuracy of the measurement, for instance, the depth of a field (DOF) in a reading microscope system and the outer and inner diameters of a capillary are analyzed, while illustrating that the effective DOF plays an essential role in accurate measurement.
Sarin, Hemant
2010-08-11
Much of our current understanding of microvascular permeability is based on the findings of classic experimental studies of blood capillary permeability to various-sized lipid-insoluble endogenous and non-endogenous macromolecules. According to the classic small pore theory of microvascular permeability, which was formulated on the basis of the findings of studies on the transcapillary flow rates of various-sized systemically or regionally perfused endogenous macromolecules, transcapillary exchange across the capillary wall takes place through a single population of small pores that are approximately 6 nm in diameter; whereas, according to the dual pore theory of microvascular permeability, which was formulated on the basis of the findings of studies on the accumulation of various-sized systemically or regionally perfused non-endogenous macromolecules in the locoregional tissue lymphatic drainages, transcapillary exchange across the capillary wall also takes place through a separate population of large pores, or capillary leaks, that are between 24 and 60 nm in diameter. The classification of blood capillary types on the basis of differences in the physiologic upper limits of pore size to transvascular flow highlights the differences in the transcapillary exchange routes for the transvascular transport of endogenous and non-endogenous macromolecules across the capillary walls of different blood capillary types. The findings and published data of studies on capillary wall ultrastructure and capillary microvascular permeability to lipid-insoluble endogenous and non-endogenous molecules from the 1950s to date were reviewed. In this study, the blood capillary types in different tissues and organs were classified on the basis of the physiologic upper limits of pore size to the transvascular flow of lipid-insoluble molecules. Blood capillaries were classified as non-sinusoidal or sinusoidal on the basis of capillary wall basement membrane layer continuity or lack thereof. Non-sinusoidal blood capillaries were further sub-classified as non-fenestrated or fenestrated based on the absence or presence of endothelial cells with fenestrations. The sinusoidal blood capillaries of the liver, myeloid (red) bone marrow, and spleen were sub-classified as reticuloendothelial or non-reticuloendothelial based on the phago-endocytic capacity of the endothelial cells. The physiologic upper limit of pore size for transvascular flow across capillary walls of non-sinusoidal non-fenestrated blood capillaries is less than 1 nm for those with interendothelial cell clefts lined with zona occludens junctions (i.e. brain and spinal cord), and approximately 5 nm for those with clefts lined with macula occludens junctions (i.e. skeletal muscle). The physiologic upper limit of pore size for transvascular flow across the capillary walls of non-sinusoidal fenestrated blood capillaries with diaphragmed fenestrae ranges between 6 and 12 nm (i.e. exocrine and endocrine glands); whereas, the physiologic upper limit of pore size for transvascular flow across the capillary walls of non-sinusoidal fenestrated capillaries with open 'non-diaphragmed' fenestrae is approximately 15 nm (kidney glomerulus). In the case of the sinusoidal reticuloendothelial blood capillaries of myeloid bone marrow, the transvascular transport of non-endogenous macromolecules larger than 5 nm into the bone marrow interstitial space takes place via reticuloendothelial cell-mediated phago-endocytosis and transvascular release, which is the case for systemic bone marrow imaging agents as large as 60 nm in diameter. The physiologic upper limit of pore size in the capillary walls of most non-sinusoidal blood capillaries to the transcapillary passage of lipid-insoluble endogenous and non-endogenous macromolecules ranges between 5 and 12 nm. Therefore, macromolecules larger than the physiologic upper limits of pore size in the non-sinusoidal blood capillary types generally do not accumulate within the respective tissue interstitial spaces and their lymphatic drainages. In the case of reticuloendothelial sinusoidal blood capillaries of myeloid bone marrow, however, non-endogenous macromolecules as large as 60 nm in diameter can distribute into the bone marrow interstitial space via the phago-endocytic route, and then subsequently accumulate in the locoregional lymphatic drainages of tissues following absorption into the lymphatic drainage of periosteal fibrous tissues, which is the lymphatic drainage of myeloid bone marrow. When the ultrastructural basis for transcapillary exchange across the capillary walls of different capillary types is viewed in this light, it becomes evident that the physiologic evidence for the existence of aqueous large pores ranging between 24 and 60 nm in diameter in the capillary walls of blood capillaries, is circumstantial, at best.
On the fragility of fractional-order PID controllers for FOPDT processes.
Padula, Fabrizio; Visioli, Antonio
2016-01-01
This paper analyzes the fragility issue of fractional-order proportional-integral-derivative controllers applied to integer first-order plus-dead-time processes. In particular, the effects of the variations of the controller parameters on the achieved control system robustness and performance are investigated. Results show that this kind of controllers is more fragile with respect to the standard proportional-integral-derivative controllers and therefore a significant attention should be paid by the user in their tuning. Copyright © 2015 ISA. Published by Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kubota, Jun; Tsunemura, Mami; Amano, Shigeko
1997-05-15
Two brothers with multiple visceral artery aneurysms or dilatations and diffuse connective tissue fragility who did not have clinical features of Marfan syndrome are reported. One presented with retroperitoneal hemorrhage during angiography, and idiopathic medionecrosis was proved by resection of the aneurysms. These cases belong to the heterogeneous group of Marfan syndrome. The angiographical features (multiple dilation of visceral arteries) suggests fragility of connective tissue and is predictive of hazards during and after a catheterization and operation.
Thermalization as an invisibility cloak for fragile quantum superpositions
NASA Astrophysics Data System (ADS)
Hahn, Walter; Fine, Boris V.
2017-07-01
We propose a method for protecting fragile quantum superpositions in many-particle systems from dephasing by external classical noise. We call superpositions "fragile" if dephasing occurs particularly fast, because the noise couples very differently to the superposed states. The method consists of letting a quantum superposition evolve under the internal thermalization dynamics of the system, followed by a time-reversal manipulation known as Loschmidt echo. The thermalization dynamics makes the superposed states almost indistinguishable during most of the above procedure. We validate the method by applying it to a cluster of spins ½.
Method of making tapered capillary tips with constant inner diameters
Kelly, Ryan T [West Richland, WA; Page, Jason S [Kennewick, WA; Tang, Keqi [Richland, WA; Smith, Richard D [Richland, WA
2009-02-17
Methods of forming electrospray ionization emitter tips are disclosed herein. In one embodiment, an end portion of a capillary tube can be immersed into an etchant, wherein the etchant forms a concave meniscus on the outer surface of the capillary. Variable etching rates in the meniscus can cause an external taper to form. While etching the outer surface of the capillary wall, a fluid can be flowed through the interior of the capillary tube. Etching continues until the immersed portion of the capillary tube is completely etched away.
Chemical microreactor and method thereof
Morse, Jeffrey D [Martinez, CA; Jankowski, Alan [Livermore, CA
2011-08-09
A method for forming a chemical microreactor includes forming at least one capillary microchannel in a substrate having at least one inlet and at least one outlet, integrating at least one heater into the chemical microreactor, interfacing the capillary microchannel with a liquid chemical reservoir at the inlet of the capillary microchannel, and interfacing the capillary microchannel with a porous membrane near the outlet of the capillary microchannel, the porous membrane being positioned beyond the outlet of the capillary microchannel, wherein the porous membrane has at least one catalyst material imbedded therein.
Kumari, Daman; Swaroop, Manju; Southall, Noel; Huang, Wenwei; Zheng, Wei; Usdin, Karen
2015-07-01
: Fragile X syndrome (FXS), the most common form of inherited cognitive disability, is caused by a deficiency of the fragile X mental retardation protein (FMRP). In most patients, the absence of FMRP is due to an aberrant transcriptional silencing of the fragile X mental retardation 1 (FMR1) gene. FXS has no cure, and the available treatments only provide symptomatic relief. Given that FMR1 gene silencing in FXS patient cells can be partially reversed by treatment with compounds that target repressive epigenetic marks, restoring FMRP expression could be one approach for the treatment of FXS. We describe a homogeneous and highly sensitive time-resolved fluorescence resonance energy transfer assay for FMRP detection in a 1,536-well plate format. Using neural stem cells differentiated from an FXS patient-derived induced pluripotent stem cell (iPSC) line that does not express any FMRP, we screened a collection of approximately 5,000 known tool compounds and approved drugs using this FMRP assay and identified 6 compounds that modestly increase FMR1 gene expression in FXS patient cells. Although none of these compounds resulted in clinically relevant levels of FMR1 mRNA, our data provide proof of principle that this assay combined with FXS patient-derived neural stem cells can be used in a high-throughput format to identify better lead compounds for FXS drug development. In this study, a specific and sensitive fluorescence resonance energy transfer-based assay for fragile X mental retardation protein detection was developed and optimized for high-throughput screening (HTS) of compound libraries using fragile X syndrome (FXS) patient-derived neural stem cells. The data suggest that this HTS format will be useful for the identification of better lead compounds for developing new therapeutics for FXS. This assay can also be adapted for FMRP detection in clinical and research settings. ©AlphaMed Press.
Senay, A; Delisle, J; Raynauld, J P; Morin, S N; Fernandes, J C
2016-04-01
We determined if nurses can manage osteoporotic fractures in a fracture liaison service by asking a rheumatologist and an internist to assess their clinical decisions. Experts agreed on more than 94 % of all nurses' actions for 525 fragility fracture patients, showing that their management is efficient and safe. A major care gap exists in the investigation of bone fragility and initiation of treatment for individuals who have sustained a fragility fracture. The implementation of a fracture liaison service (FLS) managed by nurses could be the key in resolving this problem. The aim of this project was to obtain agreement between physicians' and nurses' clinical decisions and evaluate if the algorithm of care is efficient and reliable for the management of a FLS. Clinical decisions of nurses for 525 subjects in a fracture liaison service between 2010 and 2013 were assessed by two independent physicians with expertise in osteoporosis treatment. Nurses succeeded in identifying all patients at risk and needed to refer 27 % of patients to an MD. Thereby, they managed autonomously 73 % of fragility fracture patients. No needless referrals were made according to assessing physicians. Agreement between each evaluator and nurses was of >97 %. Physicians' decisions were the same in >96 %, and Gwet AC11 coefficient was of >0.960 (almost perfect level of agreement). All major comorbidities were adequately managed. High agreement between nurses' and physicians' clinical decisions indicate that the independent management by nurses of a fracture liaison service is safe and should strongly be recommended in the care of patients with a fragility fracture. This kind of intervention could help resolve the existing care gap in bone fragility care as well as the societal economic burden associated with prevention and treatment of fragility fractures.
Clinicians' experiences with the fragile X clinical and research consortium.
Liu, Jessica A; Hagerman, Randi J; Miller, Robert M; Craft, Lisa T; Finucane, Brenda; Tartaglia, Nicole; Berry-Kravis, Elizabeth M; Sherman, Stephanie L; Kidd, Sharon A; Cohen, Jeffrey
2016-12-01
The objectives of the study were to assess the attitudes and experiences of clinicians involved in a consortium of clinics serving people with fragile X-associated disorders to gauge satisfaction with the consortium and its efforts to improve quality of life for patients and the community. An internet survey was sent to 26 fragile X (FX) clinic directors participating in the Fragile X Clinical and Research Consortium (FXCRC). Respondents were asked to complete 19 questions on consortium performance and outcomes relevant for their own clinic. The response rate was 84% (22/26), with two surveys providing incomplete data. Assistance with clinic establishment, opportunities for research collaborations, and access to colleagues and information were highly valued. Approximately 76% of clinicians reported improvements in patient care and 60% reported an increase in patient services. There was a 57% increase in participation in a FX-related clinical trial among clinics since joining the FXCRC (24% vs. 81%). Overall, respondents reported primarily positive experiences from participation in the FXCRC. Common suggestions for improvement included additional financial support and increased utilization of collected patient data for research purposes. Additionally, a Clinic Services Checklist was administered annually to examine changes in services offered over time. There were several important changes regarding the provision of services by clinics, often with multiple clinics changing with respect to a service. In conclusion, the FXCRC has led to the establishment and sustainment of fragile X clinics in the U.S., fostered cooperation among fragile X clinicians, and provided clinics with a platform to share recommendations and best practices to maximize quality of life for their patients and the overall fragile X community. The results from the survey and checklist also provide suggestions to strengthen the FXCRC and enhance future collaborations among FXCRC members. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.
Laws of physics help explain capillary non-perfusion in diabetic retinopathy.
Stefánsson, E; Chan, Y K; Bek, T; Hardarson, S H; Wong, D; Wilson, D I
2018-02-01
The purpose is to use laws of physics to elucidate the mechanisms behind capillary non-perfusion in diabetic retinopathy. In diabetic retinopathy, loss of pericytes weakens capillary walls and the vessel dilates. A dilated capillary has reduced resistance to flow, therefore increased flow in that vessel and decreased in adjoining capillaries. A preferential shunt vessel is thus formed from the dilated capillary and the adjacent capillaries become non-perfused. We apply the laws of Laplace and Hagen-Poiseuille to better understand the phenomena that lead to capillary non-perfusion. These laws of physics can give a foundation for physical or mathematical models to further elucidate this field of study. The law of Laplace predicts that a weaker vessel wall will dilate, assuming constant transmural pressure. The Hagen-Poiseuille equation for flow and the Ostwald-de Waele relationship for viscosity predict that a dilated vessel will receive a higher portion of the fluid flow than the adjoining capillaries. Viscosity will decrease in the dilated vessel, furthering the imbalance and resulting in a patch of non-perfused capillaries next to the dilated 'preferential' shunt vessel. Physical principles support or inspire novel hypotheses to explain poorly understood phenomena in ophthalmology. This thesis of pericyte death and capillary remodelling, which was first proposed by Cogan and Kuwabara, already agrees with histological and angiographical observations in diabetic retinopathy. We have shown that it is also supported by classical laws of physics.
Fragile X-Associated Tremor and Ataxia Syndrome (FXTAS)
... Director NIH awards $35 Million for Centers for Collaborative Research in Fragile X Men’s Health is the Focus in ... Safe to Sleep® National Child & Maternal Health Education Program RELATED WEBSITES NIH.gov HHS.gov USA. ...
DaWalt, Leann Smith; Usher, Lauren V; Greenberg, Jan S; Mailick, Marsha R
2017-12-01
Friendships and social participation are key domains of quality of life for individuals with intellectual disabilities. This study examined the friendships, social and recreational activities, and family social networks of individuals with intellectual disabilities from two distinct diagnostic groups: individuals diagnosed with fragile X syndrome (n = 81) compared with those diagnosed with autistic disorder (n = 226). Within each diagnostic group, individuals in two developmental stages were compared: adolescence and adulthood. Quality of life in friendships and social participation domains was notably low for individuals with fragile X and those with autism. Individuals with fragile X had more friendships and a less negative social impact on the family than individuals with autism. Across both groups, adolescents spent less time with friends and neighbors, and more time in exercising, than did adults.
Fragile X syndrome: A review of clinical management
Lozano, Reymundo; Azarang, Atoosa; Wilaisakditipakorn, Tanaporn; Hagerman, Randi J
2016-01-01
Summary The fragile X mental retardation 1 gene, which codes for the fragile X mental retardation 1 protein, usually has 5 to 40 CGG repeats in the 5′ untranslated promoter. The full mutation is the almost always the cause of fragile X syndrome (FXS). The prevalence of FXS is about 1 in 4,000 to 1 in 7,000 in the general population although the prevalence varies in different regions of the world. FXS is the most common inherited cause of intellectual disability and autism. The understanding of the neurobiology of FXS has led to many targeted treatments, but none have cured this disorder. The treatment of the medical problems and associated behaviors remain the most useful intervention for children with FXS. In this review, we focus on the non-pharmacological and pharmacological management of medical and behavioral problems associated with FXS as well as current recommendations for follow-up and surveillance. PMID:27672537
Repurposing available drugs for neurodevelopmental disorders: The fragile X experience.
Tranfaglia, Michael R; Thibodeaux, Clare; Mason, Daniel J; Brown, David; Roberts, Ian; Smith, Richard; Guilliams, Tim; Cogram, Patricia
2018-05-04
Many available drugs have been repurposed as treatments for neurodevelopmental disorders. In the specific case of fragile X syndrome, many clinical trials of available drugs have been conducted with the goal of disease modification. In some cases, detailed understanding of basic disease mechanisms has guided the choice of drugs for clinical trials, and several notable successes in fragile X clinical trials have led to common use of drugs such as minocycline in routine medical practice. Newer technologies like Disease-Gene Expression Matching (DGEM) may allow for more rapid identification of promising repurposing candidates. A DGEM study predicted that sulindac could be therapeutic for fragile X, and subsequent preclinical validation studies have shown promising results. The use of combinations of available drugs and nutraceuticals has the potential to greatly expand the options for repurposing, and may even be a viable business strategy. Copyright © 2018 Elsevier Ltd. All rights reserved.
Fragile Families in the American Welfare State
Garfinkel, Irwin; Zilanawala, Afshin
2016-01-01
The proportion of children born out of wedlock is now over 40 percent. At birth, about half of these parents are co-habiting. This paper examines data from the Fragile Families and Child Wellbeing study (N = 4,271) to describe for the first time the role of welfare state benefits in the economic lives of married, cohabiting, and single parent families with young children. Surprisingly, total welfare state benefits received by the three family types are relatively similar. Nearly half of the full incomes of fragile families come from welfare state transfers. For single parent families the proportion is slightly more than two thirds. Though aggregate welfare state transfers are approximately equal across family type and thus change very little as marital status changes, these transfers and the taxes required to finance them cushion family status changes and substantially narrow the gap in full income between married and fragile families. PMID:27114616
Multiplexed fluorescence detector system for capillary electrophoresis
Yeung, E.S.; Taylor, J.A.
1996-03-12
A fluorescence detection system for capillary electrophoresis is provided wherein the detection system can simultaneously excite fluorescence and substantially simultaneously monitor separations in multiple capillaries. This multiplexing approach involves laser irradiation of a sample in a plurality of capillaries through optical fibers that are coupled individually with the capillaries. The array is imaged orthogonally through a microscope onto a charge-coupled device camera for signal analysis. 14 figs.
Multiplexed fluorescence detector system for capillary electrophoresis
Yeung, E.S.; Taylor, J.A.
1994-06-28
A fluorescence detection system for capillary electrophoresis is provided wherein the detection system can simultaneously excite fluorescence and substantially simultaneously monitor separations in multiple capillaries. This multiplexing approach involves laser irradiation of a sample in a plurality of capillaries through optical fibers that are coupled individually with the capillaries. The array is imaged orthogonally through a microscope onto a charge-coupled device camera for signal analysis. 14 figures.
Multiplexed fluorescence detector system for capillary electrophoresis
Yeung, Edward S.; Taylor, John A.
1996-03-12
A fluorescence detection system for capillary electrophoresis is provided wherein the detection system can simultaneously excite fluorescence and substantially simultaneously monitor separations in multiple capillaries. This multiplexing approach involves laser irradiation of a sample in a plurality of capillaries through optical fibers that are coupled individually with the capillaries. The array is imaged orthogonally through a microscope onto a charge-coupled device camera for signal analysis.
Multiplexed fluorescence detector system for capillary electrophoresis
Yeung, Edward S.; Taylor, John A.
1994-06-28
A fluorescence detection system for capillary electrophoresis is provided wherein the detection system can simultaneously excite fluorescence and substantially simultaneously monitor separations in multiple capillaries. This multiplexing approach involves laser irradiation of a sample in a plurality of capillaries through optical fibers that are coupled individually with the capillaries. The array is imaged orthogonally through a microscope onto a charge-coupled device camera for signal analysis.
NASA Astrophysics Data System (ADS)
Comanns, Philipp; Winands, Kai; Pothen, Mario; Bott, Raya A.; Wagner, Hermann; Baumgartner, Werner
2016-04-01
Moisture-harvesting lizards, such as the Texas horned lizard Phrynosoma cornutum, have remarkable adaptations for inhabiting arid regions. Special skin structures, in particular capillary channels in between imbricate overlapping scales, enable the lizard to collect water by capillarity and to transport it to the snout for ingestion. This fluid transport is passive and directional towards the lizard's snout. The directionality is based on geometric principles, namely on a periodic pattern of interconnected half-open capillary channels that narrow and widen. Following a biomimetic approach, these principles were transferred to technical prototype design and manufacturing. Capillary structures, 50 μm to 300 μm wide and approx. 70 μm deep, were realized by use of a pulsed picosecond laser in hot working tool steel, hardened to 52 HRC. In order to achieve highest functionality, strategies were developed to minimize potential structural inaccuracies, which can occur at the bottom of the capillary structures caused by the laser process. Such inaccuracies are in the range of 10 μm to 15 μm and form sub-capillary structures with greater capillary forces than the main channels. Hence, an Acceleration Compensation Algorithm was developed for the laser process to minimize or even avoid these inaccuracies. The capillary design was also identified to have substantial influence; by a hexagonal capillary network of non-parallel capillaries potential influences of sub-capillaries on the functionality were reduced to realize a robust passive directional capillary transport. Such smart surface structures can lead to improvements of technical systems by decreasing energy consumption and increasing the resource efficiency.
Nailfold capillaroscopy in diabetes mellitus.
Maldonado, G; Guerrero, R; Paredes, C; Ríos, C
2017-07-01
Diabetes mellitus (DM) is characterized by chronic hyperglycemia states and the development of specific microvascular disorders such as retinopathy and nephropathy. Conventional methods are used to study the vascular compromise of this entity, however, the use of capillaroscopy for the evaluation of capillary microarchitecture is not frequently used. Observational and descriptive study of 65 patients with an established diagnosis of DM and a control group that underwent an initial capillaroscopy examination. The parameters considered were: Capillary diameter (ectasia and giant capillaries), cross-linked, tortuous, arborified capillaries, avascular zones, haemorrhages, dominant morphology, visibility of the subpapillary venous plexus (SPVP), cuticulitis and SD pattern. Capillaroscopy was performed in 65 patients, the findings were: tortous capillaries (63%), crosslinked capillaries (59%), avascular areas (48%), ectasias (39%), giant capillaries (11%). The capillaroscopic findings were evident in the majority of the studied population, 83%, compared to 17% who did not have capillaroscopic alterations. Significant capillaroscopic changes were demonstrated in patients with DM, in turn, we described a specific pattern consisting of: capillary dilatation, avascular zones and tortuous capillaries. Patients with more comorbidities and evolution of the disease showed greater microvascular damage. Copyright © 2017 Elsevier Inc. All rights reserved.
Lu, Joann J.; Wang, Shili; Li, Guanbin; Wang, Wei; Pu, Qiaosheng; Liu, Shaorong
2012-01-01
In this report, we introduce a chip-capillary hybrid device to integrate capillary isoelectric focusing (CIEF) with parallel capillary sodium dodecyl sulfate – polyacrylamide gel electrophoresis (SDS-PAGE) or capillary gel electrophoresis (CGE) toward automating two-dimensional (2D) protein separations. The hybrid device consists of three chips that are butted together. The middle chip can be moved between two positions to re-route the fluidic paths, which enables the performance of CIEF and injection of proteins partially resolved by CIEF to CGE capillaries for parallel CGE separations in a continuous and automated fashion. Capillaries are attached to the other two chips to facilitate CIEF and CGE separations and to extend the effective lengths of CGE columns. Specifically, we illustrate the working principle of the hybrid device, develop protocols for producing and preparing the hybrid device, and demonstrate the feasibility of using this hybrid device for automated injection of CIEF-separated sample to parallel CGE for 2D protein separations. Potentials and problems associated with the hybrid device are also discussed. PMID:22830584
ESR evidence for 2 coexisting liquid phases in deeply supercooled bulk water
Banerjee, D.; Bhat, S. N.; Bhat, S. V.; Leporini, D.
2009-01-01
Using electron spin resonance spectroscopy (ESR), we measure the rotational mobility of probe molecules highly diluted in deeply supercooled bulk water and negligibly constrained by the possible ice fraction. The mobility increases above the putative glass transition temperature of water, Tg = 136 K, and smoothly connects to the thermodynamically stable region by traversing the so called “no man's land” (the range 150–235 K), where it is believed that the homogeneous nucleation of ice suppresses the liquid water. Two coexisting fractions of the probe molecules are evidenced. The 2 fractions exhibit different mobility and fragility; the slower one is thermally activated (low fragility) and is larger at low temperatures below a fragile-to-strong dynamic cross-over at ≈225 K. The reorientation of the probe molecules decouples from the viscosity below ≈225 K. The translational diffusion of water exhibits a corresponding decoupling at the same temperature [Chen S-H, et al. (2006) The violation of the Stokes–Einstein relation in supercooled water. Proc Natl Acad Sci USA 103:12974–12978]. The present findings are consistent with key issues concerning both the statics and the dynamics of supercooled water, namely the large structural fluctuations [Poole PH, Sciortino F, Essmann U, Stanley HE (1992) Phase behavior of metastable water. Nature 360:324–328] and the fragile-to-strong dynamic cross-over at ≈228 K [Ito K, Moynihan CT, Angell CA (1999) Thermodynamic determination of fragility in liquids and a fragile-to-strong liquid transition in water. Nature 398:492–494]. PMID:19556546
TARGETED TREATMENTS IN AUTISM AND FRAGILE X SYNDROME
Gürkan, C. Kağan; Hagerman, Randi J.
2012-01-01
Autism is a neurodevelopmental disorder consisting of a constellation of symptoms that sometimes occur as part of a complex disorder characterized by impairments in social interaction, communication and behavioral domains. It is a highly disabling disorder and there is a need for treatment targeting the core symptoms. Although autism is accepted as highly heritable, there is no genetic cure at this time. Autism is shown to be linked to several genes and is a feature of some complex genetic disorders, including fragile X syndrome (FXS), fragile X premutation involvement, tuberous sclerosis and Rett syndrome. The term autism spectrum disorders (ASDs) covers autism, Asperger syndrome and pervasive developmental disorders (PDD-NOS) and the etiologies are heterogeneous. In recent years, targeted treatments have been developed for several disorders that have a known specific genetic cause leading to autism. Since there are significant molecular and neurobiological overlaps among disorders, targeted treatments developed for a specific disorder may be helpful in ASD of unknown etiology. Examples of this are two drug classes developed to treat FXS, Arbaclofen, a GABAB agonist, and mGluR5 antagonists, and both may be helpful in autism without FXS. The mGluR5 antagonists are also likely to have a benefit in the aging problems of fragile X premutation carriers, the fragile X –associated tremor ataxia syndrome (FXTAS) and the Parkinsonism that can occur in aging patients with fragile X syndrome. Targeted treatments in FXS which has a well known genetic etiology may lead to new targeted treatments in autism. PMID:23162607
Martin-Bell syndrome; Marker X syndrome ... Fragile X syndrome is caused by a change in a gene called FMR1 . A small part of the gene ... repeated several times in one area of the X chromosome. The more repeats, the more likely the ...
NASA Astrophysics Data System (ADS)
Suppasri, A.; Charvet, I.; Leelawat, N.; Fukutani, Y.; Muhari, A.; Futami, T.; Imamura, F.
2014-12-01
This study focused in turn on detailed data of buildings and boats damage caused by the 2011 tsunami in order to understand its main causes and provide damage probability estimates. Tsunami-induced building damage data was collected from field surveys, and includes inundation depth, building material, number of stories and occupancy type for more than 80,000 buildings. Numerical simulations with high resolution bathymetry and topography data were conducted to obtain characteristic tsunami measures such as flow velocity. These data were analyzed using advanced statistical methods, ordinal regression analysis to create not only empirical 2D tsunami fragility curves, but also 3D tsunami fragility surfaces for the first time. The effect of floating debris was also considered, by using a binary indicator of debris impact based on the proximity of a structure from a debris source (i.e. washed away building). Both the 2D and 3D fragility analyses provided results for each different building damage level, and different topography. While 2D fragility curves provide easily interpretable results relating tsunami flow depth to damage probability for different damage levels, 3D fragility surfaces allow for several influential tsunami parameters to be taken into account thus reduce uncertainty in the probability estimations. More than 20,000 damaged boats were used in the analysis similar to the one carried out on the buildings. Detailed data for each boat comprises information on the damage ratio (paid value over insured value), tonnage, engine type, material type and damage classification. The 2D and 3D fragility analyses were developed using representative tsunami heights for each port obtained from field surveys and flow velocities obtained from the aforementioned simulations. The results are currently being adapted for practical disaster mitigation. They are being integrated with the probabilistic tsunami hazard analysis, in order to create offshore and onshore probabilistic hazard maps. Through the GPS and embedded calculation function based on the aforementioned fragility results, these applications can be used in the field for a quick estimation of possible building damage, as well as a decision support system for fishermen (whether or not they should move their boats to the deep sea upon tsunami arrival).
Bresciani, Francesca; Pietra, Marco; Corradini, Sara; Giunti, Massimo; Fracassi, Federico
2014-01-01
In human medicine, diagnosis of diabetic ketoacidosis (DKA) is usually based on measurement of capillary 3-β-hydroxybutyrate (3-HB) with a hand held ketone sensor. This study was conducted to determine if measurement of capillary 3-HB could be useful for the diagnosis and monitoring of canine DKA. Fifteen dogs with diabetic ketosis and 10 with DKA were evaluated. Paired measurements of 3-HB of capillary and venous blood samples were analysed by the electrochemical sensor and reference method. Use of capillary 3-HB measurement during DKA management was then evaluated through simultaneous measurements of capillary 3-HB, urinary AcAc and venous blood gas analysis. Good agreement between capillary and venous 3-HB measurement was detected by the electrochemical sensor and reference method. Monitoring treatment of DKA revealed a significant correlation between capillary 3-HB and acidosis markers, while no significant correlation was observed between AcAc and acidosis markers. A cut-off value of capillary blood 3-HB > 3.8 mmol/L for diagnosis of DKA resulted in 70% and 92% sensitivity and specificity. The electrochemical sensor accurately measures 3-HB concentration in both capillary and venous blood samples, is accurate in diagnosing canine DKA, and appears to reflect the patient's metabolic status during DKA treatment.
Capillary leak syndrome: etiologies, pathophysiology, and management.
Siddall, Eric; Khatri, Minesh; Radhakrishnan, Jai
2017-07-01
In various human diseases, an increase in capillary permeability to proteins leads to the loss of protein-rich fluid from the intravascular to the interstitial space. Although sepsis is the disease most commonly associated with this phenomenon, many other diseases can lead to a "sepsis-like" syndrome with manifestations of diffuse pitting edema, exudative serous cavity effusions, noncardiogenic pulmonary edema, hypotension, and, in some cases, hypovolemic shock with multiple-organ failure. The term capillary leak syndrome has been used to describe this constellation of disease manifestations associated with an increased capillary permeability to proteins. Diseases other than sepsis that can result in capillary leak syndrome include the idiopathic systemic capillary leak syndrome or Clarkson's disease, engraftment syndrome, differentiation syndrome, the ovarian hyperstimulation syndrome, hemophagocytic lymphohistiocytosis, viral hemorrhagic fevers, autoimmune diseases, snakebite envenomation, and ricin poisoning. Drugs including some interleukins, some monoclonal antibodies, and gemcitabine can also cause capillary leak syndrome. Acute kidney injury is commonly seen in all of these diseases. In addition to hypotension, cytokines are likely to be important in the pathophysiology of acute kidney injury in capillary leak syndrome. Fluid management is a critical part of the treatment of capillary leak syndrome; hypovolemia and hypotension can cause organ injury, whereas capillary leakage of administered fluid can worsen organ edema leading to progressive organ injury. The purpose of this article is to discuss the diseases other than sepsis that produce capillary leak and review their collective pathophysiology and treatment. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.
[The diagnostic significance of nailfold video-capillaroscopy in systemic sclerosis].
Li, Lin-Guang; Zhang, Jiang-Lin; Liu, Xiu-Hua; Huang, Feng
2012-05-01
To observe nailfold capillary changes in a cohort of connective tissue disease (CTD) with Raynaud's phenomenon (RP) and to explore the diagnostic value of nailfold video-capillaroscopy (NVC) in systemic sclerosis (SSc). Sixty CTD patients with RP divided into SSc group (n = 36) and non-SSc group (n = 24) were referred to an experienced operator for NVC. The patients had decreased capillary loops in SSc group with the capillary diameter more enlarged in SSc group than non-SSc group. The number of patients in SSc group with giant capillaries was 14, while 3 in non-SSc group. There were 23 patients with haemorrhages in SSc group and 9 in non-SSc group. The number of patients with severe effusion was 15 in SSc group, while 2 in non-SSc group. By using the ROC curves, indexes with AUC at least 0.7 of the input capillary diameter, the output capillary diameter, the middle capillary diameter, blood color and effusion for the diagnostic cutoff points were 18.5 µm, 24.5 µm, 19.5µm, deep red and severe effusion. With at least 2 out of the top 3 indexes, the diagnostic sensitivity and specificity of SSc were higher. CTD Patients with RP of SSc have less capillary loops, more enlarged capillaries, more giant capillaries, more severe effusion and more haemorrhages than non-SSc patients. The characteristics of nailfold capillary changes in SSc patients with RP can be helpful for the diagnosis and the differential diagnosis of SSc.
Capillary Flows Along Open Channel Conduits: The Open-Star Section
NASA Technical Reports Server (NTRS)
Weislogel, Mark; Geile, John; Chen, Yongkang; Nguyen, Thanh Tung; Callahan, Michael
2014-01-01
Capillary rise in tubes, channels, and grooves has received significant attention in the literature for over 100 years. In yet another incremental extension of such work, a transient capillary rise problem is solved for spontaneous flow along an interconnected array of open channels forming what is referred to as an 'open-star' section. This geometry possesses several attractive characteristics including passive phase separations and high diffusive gas transport. Despite the complex geometry, novel and convenient approximations for capillary pressure and viscous resistance enable closed form predictions of the flow. As part of the solution, a combined scaling approach is applied that identifies unsteady-inertial-capillary, convective-inertial-capillary, and visco-capillary transient regimes in a single parameter. Drop tower experiments are performed employing 3-D printed conduits to corroborate all findings.
Microfluidic PMMA interfaces for rectangular glass capillaries
NASA Astrophysics Data System (ADS)
Evander, Mikael; Tenje, Maria
2014-02-01
We present the design and fabrication of a polymeric capillary fluidic interface fabricated by micro-milling. The design enables the use of glass capillaries with any kind of cross-section in complex microfluidic setups. We demonstrate two different designs of the interface; a double-inlet interface for hydrodynamic focusing and a capillary interface with integrated pneumatic valves. Both capillary interfaces are presented together with examples of practical applications. This communication shows the design optimization and presents details of the fabrication process. The capillary interface opens up for the use of complex microfluidic systems in single-use glass capillaries. They also enable simple fabrication of glass/polymer hybrid devices that can be beneficial in many research fields where a pure polymer chip negatively affects the device's performance, e.g. acoustofluidics.
Capillary pumped loop body heat exchanger
NASA Technical Reports Server (NTRS)
Swanson, Theodore D. (Inventor); Wren, deceased, Paul (Inventor)
1998-01-01
A capillary pumped loop for transferring heat from one body part to another body part, the capillary pumped loop comprising a capillary evaporator for vaporizing a liquid refrigerant by absorbing heat from a warm body part, a condenser for turning a vaporized refrigerant into a liquid by transferring heat from the vaporized liquid to a cool body part, a first tube section connecting an output port of the capillary evaporator to an input of the condenser, and a second tube section connecting an output of the condenser to an input port of the capillary evaporator. A wick may be provided within the condenser. A pump may be provided between the second tube section and the input port of the capillary evaporator. Additionally, an esternal heat source or heat sink may be utilized.
Capillary density: An important parameter in nailfold capillaroscopy.
Emrani, Zahra; Karbalaie, Abdolamir; Fatemi, Alimohammad; Etehadtavakol, Mahnaz; Erlandsson, Björn-Erik
2017-01-01
Nailfold capillaroscopy is one of the various noninvasive bioengineering methods used to investigate skin microcirculation. It is an effective examination for assessing microvascular changes in the peripheral circulation; hence it has a significant role for the diagnosis of Systemic sclerosis with the classic changes of giant capillaries as well as the decline in capillary density with capillary dropout. The decline in capillary density is one of microangiopathic features existing in connective tissue disease. It is detectable with nailfold capillaroscopy. This parameter is assessed by applying quantitative measurement. In this article, we reviewed a common method for calculating the capillary density and the relation between the number of capillaries as well as the existence of digital ulcers, pulmonary arterial hypertension, autoantibodies, scleroderma patterns and different scoring system. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Bulanov, Stepan; Bagdasarov, Gennadiy; Bobrova, Nadezhda; Boldarev, Alexey; Olkhovskaya, Olga; Sasorov, Pavel; Gasilov, Vladimir; Barber, Samuel; Gonsalves, Anthony; Schroeder, Carl; van Tilborg, Jeroen; Esarey, Eric; Leemans, Wim; Levato, Tadzio; Margarone, Daniele; Korn, Georg; Kando, Masaki; Bulanov, Sergei
2017-10-01
A novel method for asymmetric focusing of electron beams is proposed. The scheme is based on the active lensing technique, which takes advantage of the strong inhomogeneous magnetic field generated inside the capillary discharge plasma to focus the ultrarelativistic electrons. The plasma and magnetic field parameters inside a capillary discharge are described theoretically and modeled with dissipative MHD simulations to enable analysis of capillaries of oblong rectangle cross-sections implying that large aspect ratio rectangular capillaries can be used to form flat electron bunches. The effect of the capillary cross-section on the electron beam focusing properties were studied using the analytical methods and simulation- derived magnetic field map showing the range of the capillary discharge parameters required for producing the high quality flat electron beams.
Montaser, Akbar; Westphal, Craig S.; Kahen, Kaveh; Rutkowski, William F.; Acon, Billy W.
2006-12-05
A nebulizer adapted for adjusting a position of a capillary tube contained within the nebulizer is provided. The nebulizer includes an elongated tubular shell having a gas input port and a gas output port, a capillary adjustment adapter for displacing the capillary tube in a lateral direction via a rotational force, and a connector for connecting the elongated tubular shell, the capillary adjustment adapter and the capillary tube.
A Zero Dimensional Time-Dependent Model of High-Pressure Ablative Capillary Discharge (Preprint)
2008-06-01
comprehensive model of capillary discharge is important to understand the physics and engineering aspects of the capillary discharge thruster. A schematic...investigators since the mid-1980s see 1-11 and references therein, satisfy both of these conditions well. These studies investigated the dynamics of high...is a comprehensive description of the radiative heat transfer in the capillary discharge. It is worth noting that in other types of capillary
DOT National Transportation Integrated Search
2016-09-01
the ISSUE : the RESEARCH : Earthquake Fragility : Assessment of Curved : and Skewed Bridges in : Mountain West Region : Reinforced concrete bridges with both skew and curvature are common in areas with complex terrains. : These bridges are irregular ...
Fragile X Syndrome: Genetic Predisposition to Psychopathology.
ERIC Educational Resources Information Center
Bregman, Joel D.; And Others
1988-01-01
Psychiatric evaluation of 14 males (ages 3-27 years) with the fragile X syndrome found pervasive hyperactivity, impulsivity, and attentional deficits, and a significant degree of anxiety. However, diagnostic criteria for persistent pervasive developmental disorder and autism were not met. (Author/DB)
Federal Register 2010, 2011, 2012, 2013, 2014
2011-03-14
... Announcement (FOA) DD11-004, and Pilot Longitudinal Data Collection to Inform Public Health--Fragile X Syndrome... Collection to Inform Public Health--Fragile X Syndrome, FOA DD11-007.'' Contact Person for More Information...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-17
... Collection To Inform Public Health--Fragile X Syndrome, DD11-007, Initial Review In accordance with Section... Collection to Inform Public Health--Fragile X Syndrome, DD11-007, initial review.'' Contact Person for More...
Jaiswal, Kishor
2013-01-01
This memo lays out a procedure for the GEM software to offer an available vulnerability function for any acceptable set of attributes that the user specifies for a particular building category. The memo also provides general guidelines on how to submit the vulnerability or fragility functions to the GEM vulnerability repository, stipulating which attributes modelers must provide so that their vulnerability or fragility functions can be queried appropriately by the vulnerability database. An important objective is to provide users guidance on limitations and applicability by providing the associated modeling assumptions and applicability of each vulnerability or fragility function.
Tuning the fragility of a glass-forming liquid by curving space.
Sausset, François; Tarjus, Gilles; Viot, Pascal
2008-10-10
We investigate the influence of space curvature, and of the associated frustration, on the dynamics of a model glass former: a monatomic liquid on the hyperbolic plane. We find that the system's fragility, i.e., the sensitivity of the relaxation time to temperature changes, increases as one decreases the frustration. As a result, curving space provides a way to tune fragility and make it as large as wanted. We also show that the nature of the emerging "dynamic heterogeneities", another distinctive feature of slowly relaxing systems, is directly connected to the presence of frustration-induced topological defects.
Clinical aspects of the fragile X syndrome.
Brown, W Ted
2012-01-01
Fragile X syndrome patients express a wide array of cognitive and other gender-specific phenotypic features. These manifestations result not only from molecular mechanisms that are altered as a result of the expansion of a CGG-repeat region in the FMR1 promoter, but also genetic factors such as founder effects and mosaicism. In this chapter, I will summarize the many and varied features of fragile X syndrome as they present themselves in a clinical setting and describe the procedures that are used to diagnose patients. Finally, I will briefly touch on recent developments that will affect patient screening in the future.
Basilici Zannetti, Emanuela; D'Agostino, Fabio; Cittadini, Noemi; Feola, Maurizio; Pennini, Annalisa; Rao, Cecilia; Vellone, Ercole; Tarantino, Umberto; Alvaro, Rosaria
2017-01-01
Osteoporosis has a significant impact on affected patients. Healthcare providers should encourage postmenopausal women to improve self-care maintenance behaviors and quality of life following a fragility fracture. The aims of this study were to a) develop two new instruments for measuring, respectively, self-care maintenance and quality of life, in postmenopausal women with osteoporosis; b) evaluate the effectiveness of a tailored educational intervention to improve self-care maintenance and quality of life after a fragility fracture in postmenopausal women. For the first aim, a cross-sectional study will be performed; for the second aim, a multicenter, quasi-experimental, interventional design will be used. A convenience sample of postmenopausal women admitted to 44 hospitals in Italy with a diagnosis of bone fragility fracture will be enrolled and surveyed at 7, 30, 60 and 180 days after discharge. Trained nurses will conduct the educational intervention. The new instruments will allow the measurement of self-care and quality of life in postmenopausal women following a fragility fracture. Through tailored educational interventions, women can be helped to take their medications correctly, adopt a healthy lifestyle, reduce the occurrence of bone fractures, and have a better quality of life.
Development of hazard-compatible building fragility and vulnerability models
Karaca, E.; Luco, N.
2008-01-01
We present a methodology for transforming the structural and non-structural fragility functions in HAZUS into a format that is compatible with conventional seismic hazard analysis information. The methodology makes use of the building capacity (or pushover) curves and related building parameters provided in HAZUS. Instead of the capacity spectrum method applied in HAZUS, building response is estimated by inelastic response history analysis of corresponding single-degree-of-freedom systems under a large number of earthquake records. Statistics of the building response are used with the damage state definitions from HAZUS to derive fragility models conditioned on spectral acceleration values. Using the developed fragility models for structural and nonstructural building components, with corresponding damage state loss ratios from HAZUS, we also derive building vulnerability models relating spectral acceleration to repair costs. Whereas in HAZUS the structural and nonstructural damage states are treated as if they are independent, our vulnerability models are derived assuming "complete" nonstructural damage whenever the structural damage state is complete. We show the effects of considering this dependence on the final vulnerability models. The use of spectral acceleration (at selected vibration periods) as the ground motion intensity parameter, coupled with the careful treatment of uncertainty, makes the new fragility and vulnerability models compatible with conventional seismic hazard curves and hence useful for extensions to probabilistic damage and loss assessment.
Mosaicism for the FMR1 gene influences adaptive skills development in fragile X-affected males
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cohen, I.L.; Sudhalter, V.; Nolin, S.L.
Fragile X syndrome is one of the most common forms of inherited mental retardation, and the first of a new class of genetic disorders associated with expanded trinucleotide repeats. Previously, we found that about 41% of affected males are mosaic for this mutation in that some of their blood cells have an active fragile X gene and others do not. It has been hypothesized that these mosaic cases should show higher levels of functioning than those who have only the inactive full mutation gene, but previous studies have provided negative or equivocal results. In the present study, the cross-sectional developmentmore » of communication, self-care, socialization, and motor skills was studied in 46 males with fragile X syndrome under age 20 years as a function of two variables: age and the presence or absence of mosaicism. The rate of adaptive skills development was 2-4 times as great in mosaic cases as in full mutation cases. There was also a trend for cases with autism to be more prevalent in the full-mutation group. These results have implications for prognosis, for the utility of gene or protein replacement therapies for this disorder, and for understanding the association between mental retardation, developmental disorders, and fragile X syndrome. 21 refs., 3 figs.« less
Soares, Julio C M; Folmer, Vanderlei; Da Rocha, João B T; Nogueira, Cristina W
2014-05-01
Diabetic status is associated with an increase on oxidative stress markers in humans and animal models. We have investigated the in vitro effects of high concentrations of glucose on the profile of oxidative stress and osmotic fragility of blood from control and diabetic patients; we considered whether its antioxidant properties could afford some protection against glucose-induced osmotic fragility, and whether ebselen could act as an inhibitor of hemoglobin glycation. Raising blood glucose to 5-100 mmol/L resulted in a concentration-dependent increase of glycated hemoglobin (HbA1c; P < 0.001) and thiobarbituric acid reactive species (TBA-RS) content (P < 0.004). Non-protein SH groups (NPSH) also increased significantly as the concentration of glucose increased up to 30 mmol/L (P < 0.001). The osmotic fragility was more pronounced in blood of uncontrolled diabetic patients than in these non-diabetic subjects. Ebselen significantly reduced the glucose-induced increase in osmotic fragility and inhibited HbA1c formation (P < 0.0001). These results indicate that blood from patients with uncontrolled diabetes are more sensitive to osmotic shock than from patients with controlled diabetes and control subjects in relation to increased production of free radicals in vivo. © 2014 International Federation for Cell Biology.
NASA Astrophysics Data System (ADS)
Ravindren, Sriram; Gunasekera, Kapila; Boolchand, Punit; Micoulaut, Matthieu
2014-03-01
The kinetics of homogenization of binary AsxSe100-x melts in the As concentration range 0%
Gruss, M; Braun, K
2001-01-01
The Fragile X syndrome, a common form of mental retardation in humans, is caused by silencing the fragile X mental retardation (FMR1) gene leading to the absence of the encoded fragile X mental retardation protein 1 (FMRP). We describe morphological and behavioral abnormalities for both affected humans and Fmr1 knockout mice, a putative animal model for the human Fragile X syndrome. The aim of the present study was to identify possible neurochemical abnormalities in Fmr1 knockout mice, with particular focus on neurotransmission. Significant region-specific differences of basal neurotransmitter and metabolite levels were found between wildtype and Fmr1 knockout animals, predominantly in juveniles (post-natal days 28 to 31). Adults (postnatal days 209 to 221) showed only few abnormalities as compared with the wildtype. In juvenile knockout mice, aspartate and taurine were especially increased in cortical regions, striatum, hippocampus, cerebellum, and brainstem. In addition, juveniles showed an altered balance between excitatory and inhibitory amino acids in the caudal cortex, hippocampus, and brainstem. We detected very few differences in monoamine turnover in both age stages. The results presented here provide the first evidence that lack of FMRP expression in FMRP knockout mice is accompanied by age-dependent, region-specific alterations in neurotransmission.
Klusek, Jessica; McGrath, Sara E; Abbeduto, Leonard; Roberts, Jane E
2016-02-01
Pragmatic language difficulties have been documented as part of the FMR1 premutation phenotype, yet the interplay between these features in mothers and the language outcomes of their children with fragile X syndrome is unknown. This study aimed to determine whether pragmatic language difficulties in mothers with the FMR1 premutation are related to the language development of their children. Twenty-seven mothers with the FMR1 premutation and their adolescent/young adult sons with fragile X syndrome participated. Maternal pragmatic language violations were rated from conversational samples using the Pragmatic Rating Scale (Landa et al., 1992). Children completed standardized assessments of vocabulary, syntax, and reading. Maternal pragmatic language difficulties were significantly associated with poorer child receptive vocabulary and expressive syntax skills, with medium effect sizes. This work contributes to knowledge of the FMR1 premutation phenotype and its consequences at the family level, with the goal of identifying modifiable aspects of the child's language-learning environment that may promote the selection of treatments targeting the specific needs of families affected by fragile X. Findings contribute to our understanding of the multifaceted environment in which children with fragile X syndrome learn language and highlight the importance of family-centered intervention practices for this group.
Geometry-induced phase transition in fluids: Capillary prewetting
NASA Astrophysics Data System (ADS)
Yatsyshin, Petr; Savva, Nikos; Kalliadasis, Serafim
2013-02-01
We report a new first-order phase transition preceding capillary condensation and corresponding to the discontinuous formation of a curved liquid meniscus. Using a mean-field microscopic approach based on the density functional theory we compute the complete phase diagram of a prototypical two-dimensional system exhibiting capillary condensation, namely that of a fluid with long-ranged dispersion intermolecular forces which is spatially confined by a substrate forming a semi-infinite rectangular pore exerting long-ranged dispersion forces on the fluid. In the T-μ plane the phase line of the new transition is tangential to the capillary condensation line at the capillary wetting temperature Tcw. The surface phase behavior of the system maps to planar wetting with the phase line of the new transition, termed capillary prewetting, mapping to the planar prewetting line. If capillary condensation is approached isothermally with T>Tcw, the meniscus forms at the capping wall and unbinds continuously, making capillary condensation a second-order phenomenon. We compute the corresponding critical exponent for the divergence of adsorption.
NASA Astrophysics Data System (ADS)
Kuroda, S.; Ishii, N.; Morii, T.
2017-12-01
Capillary barriers have been known as the method to protect subsurface regions against infiltration from soil surface. It is caused by essentially heterogeneous structure in permeability or soil physical property and produce non-uniform infiltration process then, in order to estimate the actual situation of the capillary barrier effect, the site-characterization with imaging technique like geophysical prospecting is effective. In this study, we examine the applicability of GPR to characterization for capillary barriers. We built a sand box with 90x340x90cm in which a thin high-permeable gravel layer was embedded as a capillary barrier. We conducted an infiltration test in the sand box using porous tube array for irrigation. It is expected to lead to non-uniform flow of soil water induced by capillary barrier effects. We monitored this process by various types of GPR measurements, including time-lapsed common offset profiling (COP) with multi- frequency antenna and transmission measurements like cross-borehole radar. At first, we conducted GPR common-offset survey. It could show the depth of capillary barrier in sand box. After that we conducted the infiltration test and GPR monitoring for infiltration process. GPR profiles can detect the wetting front and estimate water content change in the soil layer above the capillary barrier. From spatial change in these results we can estimate the effect of capillary barrier and the zone where the break through occur or not. Based on these results, we will discuss the applicability of GPR for monitoring the phenomena around the capillary barrier of soil. At first, we conducted GPR common-offset survey. It could show the depth of capillary barrier in sand box. After that we conducted the infiltration test and GPR monitoring for infiltration process. GPR profiles can detect the wetting front and estimate water content change in the soil layer above the capillary barrier. From spatial change in these results we can estimate the effect of capillary barrier and the zone where the break through occur. Based on these results, we will discuss the applicability of GPR for monitoring the phenomena around the capillary barrier of soil.
Noise suppressing capillary separation system
Yeung, Edward S.; Xue, Yongjun
1996-07-30
A noise-suppressing capillary separation system for detecting the real-time presence or concentration of an analyte in a sample is provided. The system contains a capillary separation means through which the analyte is moved, a coherent light source that generates a beam which is split into a reference beam and a sample beam that irradiate the capillary, and a detector for detecting the reference beam and the sample beam light that transmits through the capillary. The laser beam is of a wavelength effective to be absorbed by a chromophore in the capillary. The system includes a noise suppressing system to improve performance and accuracy without signal averaging or multiple scans.
Gas sampling system for a mass spectrometer
Taylor, Charles E; Ladner, Edward P
2003-12-30
The present invention relates generally to a gas sampling system, and specifically to a gas sampling system for transporting a hazardous process gas to a remotely located mass spectrometer. The gas sampling system includes a capillary tube having a predetermined capillary length and capillary diameter in communication with the supply of process gas and the mass spectrometer, a flexible tube surrounding and coaxial with the capillary tube intermediate the supply of process gas and the mass spectrometer, a heat transfer tube surrounding and coaxial with the capillary tube, and a heating device in communication the heat transfer tube for substantially preventing condensation of the process gas within the capillary tube.
Noise suppressing capillary separation system
Yeung, E.S.; Xue, Y.
1996-07-30
A noise-suppressing capillary separation system for detecting the real-time presence or concentration of an analyte in a sample is provided. The system contains a capillary separation means through which the analyte is moved, a coherent light source that generates a beam which is split into a reference beam and a sample beam that irradiate the capillary, and a detector for detecting the reference beam and the sample beam light that transmits through the capillary. The laser beam is of a wavelength effective to be absorbed by a chromophore in the capillary. The system includes a noise suppressing system to improve performance and accuracy without signal averaging or multiple scans. 13 figs.
Wu, Nan; Wang, Siming; Yang, Ye; Song, Jiayi; Su, Ping; Yang, Yi
2018-07-01
A novel type of trypsin capillary microreactor was developed based on a DNA-directed immobilization (DDI) technique applied to a fused-silica capillary modified with polyamidoamine (PAMAM) dendrimers. Trypsin binding to the inner wall of the capillary was confirmed by confocal laser scanning microscopy. The properties of the trypsin-DNA conjugated, PAMAM-modified capillary microreactor were investigated by monitoring hydrolysis of Nα-benzoyl- L -arginine ethyl ester. Through the hybridization and dehybridization of the DNA, the inner wall of the capillary functionalized with trypsin can be regenerated, thus indicating the renewability of this enzyme microreactor. In addition, these results demonstrated that introduction of PAMAM enabled higher amounts of trypsin to be immobilized, markedly improving the enzymolysis efficiency, compared with traditional modified capillaries. The digestion performance of the trypsin capillary microreactor was further evaluated by digesting cytochrome C, and a peptide numbers of 8, and a sequence coverage of 59% were obtained. This renewable and efficient immobilized trypsin capillary microreactor combines advantages of both DDI technology and PAMAM, and is potentially adaptable to high-throughput enzyme assays in biochemical and clinical research. Copyright © 2018. Published by Elsevier B.V.
Xu, Liang; Cui, Pengfei; Wang, Dongmei; Tang, Cheng; Dong, Linyi; Zhang, Can; Duan, Hongquan; Yang, Victor C
2014-01-03
In this study, poly(glycidyl methacrylate) (PGMA) nanoparticles (NPs) were prepared and chemically immobilized for the first time onto a capillary inner wall for open tubular capillary electrochromatography (OTCEC). The immobilization of PGMA NPs onto the capillary was attained by a ring-opening reaction between the NPs and an amino-silylated fused capillary inner surface. Scanning electron micrographs clearly demonstrated that the NPs were bound to the capillary inner surface in a dense monolayer. The PGMA NP-coated column was then functionalized by lysine (Lys). After fuctionalization, the capillary can afford strong anodic electroosmotic flow, especially in acidic running buffers. Separations of three amino acids (including tryptophan, tyrosine and phenylalanine) were performed in NP-modified, monolayer Lys-functionalized and bare uncoated capillaries. Results indicated that the NP-coated column can provide more retention and higher resolution for analytes due to the hydrophobic interaction between analytes and the NP-coating. Run-to-run and column-to-column reproducibilities in the separation of the amino acids using the NP-modified column were also demonstrated. Copyright © 2013 Elsevier B.V. All rights reserved.
Anders, H; Sigl, T; Schattenkirchner, M
2001-01-01
BACKGROUND—Nailfold capillary microscopy is a routine procedure in the investigation of patients with Raynaud's phenomenon (RP). As a standard method, nailfold capillary morphology is inspected with a stereomicroscope to look for capillary abnormalities such as giant loops, avascular areas, and bushy capillaries, which have all been found to be associated with certain connective tissue diseases. AIM—To investigate prospectively whether nailfold capillary inspection using an ophthalmoscope is of equivalent diagnostic value to standard nailfold capillary microscopy. METHOD—All the fingers of 26 patients with RP were examined in a blinded fashion and compared with the final diagnosis one month later. RESULTS—All giant loops, large avascular areas, and bushy capillaries were identified by both methods. The correlation for moderate avascular areas and crossed capillaries was 0.93 and 0.955 respectively. The correlation for minor abnormalities that do not contribute to the differentiation between primary and secondary RP was 0.837 and 0.861 respectively. All patients were classified identically by the two methods. CONCLUSION—For the evaluation of patients with RP, nailfold capillary morphology can reliably be assessed with an ophthalmoscope. PMID:11247874
Spectrometer capillary vessel and method of making same
Linehan, John C.; Yonker, Clement R.; Zemanian, Thomas S.; Franz, James A.
1995-01-01
The present invention is an arrangement of a glass capillary tube for use in spectroscopy. In particular, the invention is a capillary arranged in a manner permitting a plurality or multiplicity of passes of a sample material through a spectroscopic measurement zone. In a preferred embodiment, the multi-pass capillary is insertable within a standard NMR sample tube. The present invention further includes a method of making the multi-pass capillary tube and an apparatus for spinning the tube.
NASA Astrophysics Data System (ADS)
Kang, Dong Hun; Yun, Tae Sup
2018-02-01
We propose a new outflow boundary condition to minimize the capillary end effect for a pore-scale CO2 displacement simulation. The Rothman-Keller lattice Boltzmann method with multi-relaxation time is implemented to manipulate a nonflat wall and inflow-outflow boundaries with physically acceptable fluid properties in 2-D microfluidic chip domain. Introducing a mean capillary pressure acting at CO2-water interface to the nonwetting fluid at the outlet effectively prevents CO2 injection pressure from suddenly dropping upon CO2 breakthrough such that the continuous CO2 invasion and the increase of CO2 saturation are allowed. This phenomenon becomes most pronounced at capillary number of logCa = -5.5, while capillary fingering and massive displacement of CO2 prevail at low and high capillary numbers, respectively. Simulations with different domain length in homogeneous and heterogeneous domains reveal that capillary pressure and CO2 saturation near the inlet are reproducible compared with those with a proposed boundary condition. The residual CO2 saturation uniquely follows the increasing tendency with increasing capillary number, corroborated by experimental evidences. The determination of the mean capillary pressure and its sensitivity are also discussed. The proposed boundary condition is commonly applicable to other pore-scale simulations to accurately capture the spatial distribution of nonwetting fluid and corresponding displacement ratio.
Tibirica, Eduardo; Rodrigues, Elba; Cobas, Roberta; Gomes, Marilia B.
2007-01-01
Microvascular function in patients with type 1 diabetes without chronic complications was assessed using skin capillary recruitment during post-occlusive reactive hyperemia (PORH). Structural (maximal) capillary density was evaluated during venous occlusion. The study included 48 consecutive outpatients aged 26.3 ± 10.8 years with type 1 diabetes (duration of 9.5 years) without chronic complications and 34 control subjects. Intravital capillary video-microscopy was used in the dynamic study of skin capillaries in the dorsum of the fingers and toes. Capillary recruitment during PORH (% increase in mean capillary density, MCD) was significantly higher in the controls than the patients in both the fingers (p < 0.001) and toes (p < 0.001). During venous occlusion, MCD increase was also higher in the controls than the patients in both the fingers (p < 0.05) and toes (p < 0.0001). In patients, no difference was found between MCD at baseline and after venous occlusion in the fingers but a decrease was observed in the toes (p < 0.001). It is concluded that skin capillary function is significantly impaired in both fingers and toes of patients with type 1 diabetes without chronic complications. Moreover, capillary density during venous occlusion did not increase in either extremity in the patients, suggesting that their capillaries at rest are already maximally recruited. PMID:17823692
Kabasakal, Y; Elvins, D M; Ring, E F; McHugh, N J
1996-01-01
OBJECTIVE: To describe and quantify the morphological characteristics of nailfold capillaries that distinguish different forms of connective tissue disease from healthy controls. METHODS: A CCD video microscope with fibreoptic illumination and PC based image processing was used to visualise nailfold capillaries and to quantify findings in 23 patients with systemic sclerosis (SSc), 22 patients with systemic lupus erythematosus (SLE), 21 patients with undifferentiated connective tissue disease (UCTD), and 38 healthy controls. RESULTS: Capillary density was reduced in SSc (5.2 (SD 1.3) capillaries/mm) compared with other patient groups and controls. The average number of enlarged capillaries/finger was high in all disease groups (5.5-6.6) compared with controls (2). However, giant capillaries were most frequent in SSc (43%) and were not present in controls. Mild and moderate avascular areas were present in all groups (35%-68%), but severe avascularity was most frequent in SSc (44%) compared with other patients (18%-19%) and controls (0%). The greatest frequency of extensive haemorrhage was in SSc (35%). CONCLUSIONS: There is a range of abnormal capillary findings in patients with connective tissue disease and healthy controls. However, certain abnormalities such as a reduced number of capillaries, severe avascularity, giant capillaries, and haemorrhage are most commonly associated with SSc. Videomicroscopy with image processing offers many technical advantages that can be exploited in further studies of nailfold capillaries. Images PMID:8774177
Surface sampling concentration and reaction probe
Van Berkel, Gary J; Elnaggar, Mariam S
2013-07-16
A method of analyzing a chemical composition of a specimen is described. The method can include providing a probe comprising an outer capillary tube and an inner capillary tube disposed co-axially within the outer capillary tube, where the inner and outer capillary tubes define a solvent capillary and a sampling capillary in fluid communication with one another at a distal end of the probe; contacting a target site on a surface of a specimen with a solvent in fluid communication with the probe; maintaining a plug volume proximate a solvent-specimen interface, wherein the plug volume is in fluid communication with the probe; draining plug sampling fluid from the plug volume through the sampling capillary; and analyzing a chemical composition of the plug sampling fluid with an analytical instrument. A system for performing the method is also described.
Surface sampling concentration and reaction probe with controller to adjust sampling position
Van Berkel, Gary J.; ElNaggar, Mariam S.
2016-07-19
A method of analyzing a chemical composition of a specimen is described. The method can include providing a probe comprising an outer capillary tube and an inner capillary tube disposed co-axially within the outer capillary tube, where the inner and outer capillary tubes define a solvent capillary and a sampling capillary in fluid communication with one another at a distal end of the probe; contacting a target site on a surface of a specimen with a solvent in fluid communication with the probe; maintaining a plug volume proximate a solvent-specimen interface, wherein the plug volume is in fluid communication with the probe; draining plug sampling fluid from the plug volume through the sampling capillary; and analyzing a chemical composition of the plug sampling fluid with an analytical instrument. A system for performing the method is also described.
Svobodová, Jana; Kofroňová, Olga; Benada, Oldřich; Král, Vladimír; Mikšík, Ivan
2017-09-29
The aim of this article is to study the modification of an inner capillary wall with sol-gel coating (pure silica sol-gel or silica sol-gel containing porphyrin-brucine conjugate) and determine its influence on the separation process using capillary electrophoresis/electrochromatography method. After modification of the inner capillary surface the separation of analytes was performed using two different phosphate buffers (pH 2.5 and 9.0) and finally the changes in electrophoretic mobilities of various samples were calculated. To confirm that the modification of the inner capillary surface was successful, the parts of the inner surfaces of capillaries were observed using scanning electron microscopy. The analytes used as testing samples were oligopeptides, nucleosides, nucleobases and finally nucleotides. Copyright © 2017 Elsevier B.V. All rights reserved.
Egu, K; Kinata-Bambino, S; Mounadi, M; Rachid El Maaqili, M; El Abbadi, N
2016-04-01
Capillary hemangiomas are benign endothelial cell neoplasms that are believed to be hamartomatous proliferations of vascular endothelial cells. The occurrence of spinal epidural capillary hemangiomas is exceedingly rare. Only 8 epidurally located cases of capillary hemangiomas in the spinal canal have been reported in the literature. We report for the first time, to our knowledge, a case of lumbosacral epidural capillary hemangioma revealed by S1 back pain and radicular pain in a 60-year-old patient, caused by an L5-S1 epidural capillary hemangioma. The neurological symptoms of the patient improved after surgery. Spinal epidural capillary hemangioma is exceedingly rare. These lesions are benign and can mimic dumbbell-shaped neurinoma. Total removal by surgery is curative. Copyright © 2015 Elsevier Masson SAS. All rights reserved.
Structure of Particle Networks in Capillary Suspensions with Wetting and Nonwetting Fluids
2016-01-01
The mechanical properties of a suspension can be dramatically altered by adding a small amount of a secondary fluid that is immiscible with the bulk phase. The substantial changes in the strength of these capillary suspensions arise due to the capillary force inducing a percolating particle network. Spatial information on the structure of the particle networks is obtained using confocal microscopy. It is possible, for the first time, to visualize the different types of percolating structures of capillary suspensions in situ. These capillary networks are unique from other types of particulate networks due to the nature of the capillary attraction. We investigate the influence of the three-phase contact angle on the structure of an oil-based capillary suspension with silica microspheres. Contact angles smaller than 90° lead to pendular networks of particles connected with single capillary bridges or clusters comparable to the funicular state in wet granular matter, whereas a different clustered structure, the capillary state, forms for angles larger than 90°. Particle pair distribution functions are obtained by image analysis, which demonstrate differences in the network microstructures. When porous particles are used, the pendular conformation also appears for apparent contact angles larger than 90°. The complex shear modulus can be correlated to these microstructural changes. When the percolating structure is formed, the complex shear modulus increases by nearly three decades. Pendular bridges lead to stronger networks than the capillary state network conformations, but the capillary state clusters are nevertheless much stronger than pure suspensions without the added liquid. PMID:26807651
21 CFR 864.6150 - Capillary blood collection tube.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Capillary blood collection tube. 864.6150 Section... blood collection tube. (a) Identification. A capillary blood collection tube is a plain or heparinized glass tube of very small diameter used to collect blood by capillary action. (b) Classification. Class I...
21 CFR 864.6150 - Capillary blood collection tube.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Capillary blood collection tube. 864.6150 Section... blood collection tube. (a) Identification. A capillary blood collection tube is a plain or heparinized glass tube of very small diameter used to collect blood by capillary action. (b) Classification. Class I...
21 CFR 864.6150 - Capillary blood collection tube.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Capillary blood collection tube. 864.6150 Section... blood collection tube. (a) Identification. A capillary blood collection tube is a plain or heparinized glass tube of very small diameter used to collect blood by capillary action. (b) Classification. Class I...
21 CFR 864.6150 - Capillary blood collection tube.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Capillary blood collection tube. 864.6150 Section... blood collection tube. (a) Identification. A capillary blood collection tube is a plain or heparinized glass tube of very small diameter used to collect blood by capillary action. (b) Classification. Class I...
21 CFR 864.6150 - Capillary blood collection tube.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Capillary blood collection tube. 864.6150 Section... blood collection tube. (a) Identification. A capillary blood collection tube is a plain or heparinized glass tube of very small diameter used to collect blood by capillary action. (b) Classification. Class I...
Navarro, Ronald A; Greene, Denise F; Burchette, Raoul; Funahashi, Tadashi; Dell, Richard
2011-07-01
Ethnic disparities in care have been documented with a number of musculoskeletal disorders including osteoporosis. We suggest a systems approach for ensuring osteoporosis care can minimize potential ethnic disparities in care. We evaluated variations in osteoporosis treatment by age, sex, and race/ethnicity by (1) measuring the rates of patients after a fragility fracture who had been evaluated by dual-energy xray absorptiometry and/or in whom antiosteoporosis treatment had been initiated and (2) determining the rates of osteoporosis treatment in patients who subsequently had a hip fracture. We implemented an integrated osteoporosis prevention program in a large health plan. Continuous screening of electronic medical records identified patients who met the criteria for screening for osteoporosis, were diagnosed with osteoporosis, or sustained a fragility fracture. At-risk patients were referred to care managers and providers to complete practice guidelines to close care gaps. Race/ethnicity was self-reported. Treatment rates after fragility fracture or osteoporosis treatment failures with later hip fracture were calculated. Data for the years 2008 to 2009 were stratified by age, sex, and race/ethnicity. Women (92.1%) were treated more often than men (75.2%) after index fragility fracture. The treatment rate after fragility fracture was similar among race/ethnic groups in either sex (women 87.4%-93.4% and men 69.3%-76.7%). Osteoporotic treatment before hip fracture was more likely in white men and women and Hispanic men than other race/ethnic and gender groups. Racial variation in osteoporosis care after fragility fracture in race/ethnic groups in this healthcare system was low when using the electronic medical record identifying care gaps, with continued reminders to osteoporosis disease management care managers and providers until those care gaps were closed.
Pathways for diffusion in the potential energy landscape of the network glass former SiO2
NASA Astrophysics Data System (ADS)
Niblett, S. P.; Biedermann, M.; Wales, D. J.; de Souza, V. K.
2017-10-01
We study the dynamical behaviour of a computer model for viscous silica, the archetypal strong glass former, and compare its diffusion mechanism with earlier studies of a fragile binary Lennard-Jones liquid. Three different methods of analysis are employed. First, the temperature and time scale dependence of the diffusion constant is analysed. Negative correlation of particle displacements influences transport properties in silica as well as in fragile liquids. We suggest that the difference between Arrhenius and super-Arrhenius diffusive behaviour results from competition between the correlation time scale and the caging time scale. Second, we analyse the dynamics using a geometrical definition of cage-breaking transitions that was proposed previously for fragile glass formers. We find that this definition accurately captures the bond rearrangement mechanisms that control transport in open network liquids, and reproduces the diffusion constants accurately at low temperatures. As the same method is applicable to both strong and fragile glass formers, we can compare correlation time scales in these two types of systems. We compare the time spent in chains of correlated cage breaks with the characteristic caging time and find that correlations in the fragile binary Lennard-Jones system persist for an order of magnitude longer than those in the strong silica system. We investigate the origin of the correlation behaviour by sampling the potential energy landscape for silica and comparing it with the binary Lennard-Jones model. We find no qualitative difference between the landscapes, but several metrics suggest that the landscape of the fragile liquid is rougher and more frustrated. Metabasins in silica are smaller than those in binary Lennard-Jones and contain fewer high-barrier processes. This difference probably leads to the observed separation of correlation and caging time scales.
Fragility and hysteretic creep in frictional granular jamming.
Bandi, M M; Rivera, M K; Krzakala, F; Ecke, R E
2013-04-01
The granular jamming transition is experimentally investigated in a two-dimensional system of frictional, bidispersed disks subject to quasistatic, uniaxial compression without vibrational disturbances (zero granular temperature). Three primary results are presented in this experimental study. First, using disks with different static friction coefficients (μ), we experimentally verify numerical results that predict jamming onset at progressively lower packing fractions with increasing friction. Second, we show that the first compression cycle measurably differs from subsequent cycles. The first cycle is fragile-a metastable configuration with simultaneous jammed and unjammed clusters-over a small packing fraction interval (φ(1)<φ<φ(2)) and exhibits simultaneous exponential rise in pressure and exponential decrease in disk displacements over the same packing fraction interval. This fragile behavior is explained through a percolation mechanism of stressed contacts where cluster growth exhibits spatial correlation with disk displacements and contributes to recent results emphasizing fragility in frictional jamming. Control experiments show that the fragile state results from the experimental incompatibility between the requirements for zero friction and zero granular temperature. Measurements with several disk materials of varying elastic moduli E and friction coefficients μ show that friction directly controls the start of the fragile state but indirectly controls the exponential pressure rise. Finally, under repetitive loading (compression) and unloading (decompression), we find the system exhibits pressure hysteresis, and the critical packing fraction φ(c) increases slowly with repetition number. This friction-induced hysteretic creep is interpreted as the granular pack's evolution from a metastable to an eventual structurally stable configuration. It is shown to depend on the quasistatic step size Δφ, which provides the only perturbative mechanism in the experimental protocol, and the friction coefficient μ, which acts to stabilize the pack.
NASA Astrophysics Data System (ADS)
Renuka, C.; Viswanatha, R.; Reddy, C. Narayana
2017-02-01
A simple, clean and energy efficient microwave heating route is used to prepare glasses in the systems xMnO-33(0.09PbCl2:0.91PbO)-(67-x) NaPO3 and xPbCl2-33PbO-(67-x) NaPO3 where 0.1 ≤ x ≤ 4 (mol%). Thermal data extracted from differential scanning calorimetry (DSC) thermograms are used to study the composition dependence of glass transition temperature (Tg), heat capacity, thermal stability and fragility. The decrease in glass transition temperature with modifier oxide (Na2O + MnO) content can be ascribed to network degradation and the volume increasing effect caused by PbCl2. The change in heat capacity of MnPb glass being greater than that of PbNP glass, suggests that MnPb glasses are more covalent than PbNP glasses. DSC thermograms taken at different heating rates (φ) reveal the dependence of Tg on φ, and the thermal stability of the glass increases due to MnO addition. Fragility aspects have also been studied by calculating the fragility functions ( {{Δ {{C}}_{{p}} }/{{{C}_{{pl}} }}{{and}}{[ {{NBO}} ]}/{{{V}_{{m}}3 {{T}}_{{g}} }}} ). Results obtained from both the fragility functions compare well and reveal the dependence of fragility functions on modifier content and PbCl2 mol%. Further, the decrease in Tg and Hv are suggested to be due to the increase in the number of non-bridging oxygens, which results in the lowering of stiffness and rigidity of the glass network. Analysis of the infrared spectra confirms that the glassy matrix is composed of P-O-P, P-O-Pb, P=O and P-O- bonding.
Fragile X mental retardation protein controls ion channel expression and activity.
Ferron, Laurent
2016-10-15
Fragile X-associated disorders are a family of genetic conditions resulting from the partial or complete loss of fragile X mental retardation protein (FMRP). Among these disorders is fragile X syndrome, the most common cause of inherited intellectual disability and autism. FMRP is an RNA-binding protein involved in the control of local translation, which has pleiotropic effects, in particular on synaptic function. Analysis of the brain FMRP transcriptome has revealed hundreds of potential mRNA targets encoding postsynaptic and presynaptic proteins, including a number of ion channels. FMRP has been confirmed to bind voltage-gated potassium channels (K v 3.1 and K v 4.2) mRNAs and regulates their expression in somatodendritic compartments of neurons. Recent studies have uncovered a number of additional roles for FMRP besides RNA regulation. FMRP was shown to directly interact with, and modulate, a number of ion channel complexes. The sodium-activated potassium (Slack) channel was the first ion channel shown to directly interact with FMRP; this interaction alters the single-channel properties of the Slack channel. FMRP was also shown to interact with the auxiliary β4 subunit of the calcium-activated potassium (BK) channel; this interaction increases calcium-dependent activation of the BK channel. More recently, FMRP was shown to directly interact with the voltage-gated calcium channel, Ca v 2.2, and reduce its trafficking to the plasma membrane. Studies performed on animal models of fragile X syndrome have revealed links between modifications of ion channel activity and changes in neuronal excitability, suggesting that these modifications could contribute to the phenotypes observed in patients with fragile X-associated disorders. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.
Surgical treatment for medically refractory focal epilepsy in a patient with fragile X syndrome.
Kenmuir, Cynthia; Richardson, Mark; Ghearing, Gena
2015-10-01
Medication resistant temporal lobe epilepsy occurs in a small population of patients with fragile X syndrome. We present the case of a 24-year-old man with medically refractory temporal lobe epilepsy and fragile X syndrome who underwent left anterior temporal lobectomy resulting in cessation of seizures. Our patient was diagnosed with fragile X syndrome with a fully mutated, fully methylated FMR1 gene resulting in 572 CGG repeats. He developed seizures initially controlled with Depakote monotherapy, but progressed to become medically refractive to combination treatment with Depakote, lamotrigine and zonisamide. Prolonged video EEG monitoring revealed interictal left temporal sharp waves and slowing as well as subclinical and clinical seizures, each with left temporal onset. 3T MRI was consistent with left mesial temporal sclerosis. After discussing the case in our multidisciplinary surgical epilepsy conference, he was referred for presurgical evaluation including neuropsychological testing and Wada testing. He underwent an asleep left anterior temporal lobectomy, sparing the superior temporal gyrus. Pathology showed neuronal loss and gliosis in the hippocampus and amygdala. Twelve months after surgery, the patient has not experienced a seizure. He is described by his parents as less perseverative and less restless. We have presented the case of a 24 year-old-man with fragile X syndrome who underwent successful left anterior temporal lobectomy for the treatment of medically refractory epilepsy who is now seizure free without further functional impairment. This case report demonstrates the feasibility of surgical treatment for a patient with comorbid fragile X syndrome and mesial temporal sclerosis. Copyright © 2015 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.
Cheng, Y Ky; Lin, C Sw; Kwok, Y Ky; Chan, Y M; Lau, T K; Leung, T Y; Choy, K W
2017-04-01
There is significant morbidity associated with fragile X syndrome. Unfortunately, most maternal carriers are clinically silent during their reproductive years. Because of this, many experts have put forward the notion of preconception or prenatal fragile X carrier screening for females. This study aimed to determine the prevalence of fragile X syndrome pre-mutation and asymptomatic full-mutation carriers in a Chinese pregnant population, and the distribution of cytosine-guanine-guanine (CGG) repeat numbers using a robust fragile X mental retardation 1 (FMR1) polymerase chain reaction assay. This was a cross-sectional survey in prospectively recruited pregnant women from a university hospital in Hong Kong. Chinese pregnant women without a family history of fragile X syndrome were recruited between April 2013 and May 2015. A specific FMR1 polymerase chain reaction assay was performed on peripheral blood to determine the CGG repeat number of the FMR1 gene. Prenatal counselling was offered to full-mutation and pre-mutation carriers. In 2650 Chinese pregnant women, two individuals with pre-mutation alleles (0.08%, one in 1325) and one asymptomatic woman with full-mutation (0.04%, one in 2650) alleles were identified. The overall prevalence of pre-mutation and full-mutation alleles was 0.11% (1 in 883). Furthermore, 30 (1.1%) individuals with intermediate alleles were detected. In the 2617 women with normal CGG repeats, the most common CGG repeat allele was 30. The overall prevalence of pre-mutation and asymptomatic full-mutation carriers in the Chinese pregnant population was one in 883, detected by a new FMR1 polymerase chain reaction assay.
Abnormal neural precursor cell regulation in the early postnatal Fragile X mouse hippocampus.
Sourial, Mary; Doering, Laurie C
2017-07-01
The regulation of neural precursor cells (NPCs) is indispensable for a properly functioning brain. Abnormalities in NPC proliferation, differentiation, survival, or integration have been linked to various neurological diseases including Fragile X syndrome. Yet, no studies have examined NPCs from the early postnatal Fragile X mouse hippocampus despite the importance of this developmental time point, which marks the highest expression level of FMRP, the protein missing in Fragile X, in the rodent hippocampus and is when hippocampal NPCs have migrated to the dentate gyrus (DG) to give rise to lifelong neurogenesis. In this study, we examined NPCs from the early postnatal hippocampus and DG of Fragile X mice (Fmr1-KO). Immunocytochemistry on neurospheres showed increased Nestin expression and decreased Ki67 expression, which collectively indicated aberrant NPC biology. Intriguingly, flow cytometric analysis of the expression of the antigens CD15, CD24, CD133, GLAST, and PSA-NCAM showed a decreased proportion of neural stem cells (GLAST + CD15 + CD133 + ) and an increased proportion of neuroblasts (PSA-NCAM + CD15 + ) in the DG of P7 Fmr1-KO mice. This was mirrored by lower expression levels of Nestin and the mitotic marker phospho-histone H3 in vivo in the P9 hippocampus, as well as a decreased proportion of cells in the G 2 /M phases of the P7 DG. Thus, the absence of FMRP leads to fewer actively cycling NPCs, coinciding with a decrease in neural stem cells and an increase in neuroblasts. Together, these results show the importance of FMRP in the developing hippocampal formation and suggest abnormalities in cell cycle regulation in Fragile X. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.
High functioning male with fragile X syndrome and fragile X-associated tremor/ataxia syndrome.
Basuta, Kirin; Schneider, Andrea; Gane, Louise; Polussa, Jonathan; Woodruff, Bryan; Pretto, Dalyir; Hagerman, Randi; Tassone, Flora
2015-09-01
Fragile X syndrome (FXS) affects individuals with more than 200 CGG repeats (full mutation) in the fragile X mental retardation 1 (FMR1) gene. Those born with FXS experience cognitive and social impairments, developmental delays, and some features of autism spectrum disorders. Carriers of a premutation (55-200 CGG repeats) are generally not severely affected early in life; however, are at high risk of developing the late onset neurodegenerative disorder, Fragile X-associated Tremor/Ataxia Syndrome (FXTAS), or Fragile X-associated Primary Ovarian Insufficiency (FXPOI), and may have other medical conditions such as developmental delay, autism spectrum disorders, hypertension, anxiety, and immune-mediated disorders. Here we present a case of a 58-year-old man with a borderline IQ, average memory skills, and executive function deficits. He met criteria for multiple psychiatric diagnoses and presented with tremor and ataxia, meeting criteria for FXTAS. Molecular testing unveiled a completely unmethylated FMR1 full mutation in peripheral blood mononucleated cells with elevated FMR1 mRNA and premutation alleles of different sizes in two other tissues (primary fibroblasts and sperm), indicating the presence of allele instability based on both inter- and intra-tissue mosaicism. The observation of FXTAS in this case of a full mutation mosaic man suggests that the pathogenic mechanism underlying this disorder is not observed exclusively in premutation carriers as it was originally thought. The concomitant presence of features of FXS and late onset neurological deterioration with probable FXTAS likely result from a combined molecular pathology of elevated FMR1 mRNA levels, a molecular hallmark of FXTAS and low FMRP expression that leads to FXS. © 2015 Wiley Periodicals, Inc.
Dysregulation of mTOR signaling in fragile X syndrome.
Sharma, Ali; Hoeffer, Charles A; Takayasu, Yukihiro; Miyawaki, Takahiro; McBride, Sean M; Klann, Eric; Zukin, R Suzanne
2010-01-13
Fragile X syndrome, the most common form of inherited mental retardation and leading genetic cause of autism, is caused by transcriptional silencing of the Fmr1 gene. The fragile X mental retardation protein (FMRP), the gene product of Fmr1, is an RNA binding protein that negatively regulates translation in neurons. The Fmr1 knock-out mouse, a model of fragile X syndrome, exhibits cognitive deficits and exaggerated metabotropic glutamate receptor (mGluR)-dependent long-term depression at CA1 synapses. However, the molecular mechanisms that link loss of function of FMRP to aberrant synaptic plasticity remain unclear. The mammalian target of rapamycin (mTOR) signaling cascade controls initiation of cap-dependent translation and is under control of mGluRs. Here we show that mTOR phosphorylation and activity are elevated in hippocampus of juvenile Fmr1 knock-out mice by four functional readouts: (1) association of mTOR with regulatory associated protein of mTOR; (2) mTOR kinase activity; (3) phosphorylation of mTOR downstream targets S6 kinase and 4E-binding protein; and (4) formation of eukaryotic initiation factor complex 4F, a critical first step in cap-dependent translation. Consistent with this, mGluR long-term depression at CA1 synapses of FMRP-deficient mice is exaggerated and rapamycin insensitive. We further show that the p110 subunit of the upstream kinase phosphatidylinositol 3-kinase (PI3K) and its upstream activator PI3K enhancer PIKE, predicted targets of FMRP, are upregulated in knock-out mice. Elevated mTOR signaling may provide a functional link between overactivation of group I mGluRs and aberrant synaptic plasticity in the fragile X mouse, mechanisms relevant to impaired cognition in fragile X syndrome.
Fragile X and autism: Intertwined at the molecular level leading to targeted treatments.
Hagerman, Randi; Hoem, Gry; Hagerman, Paul
2010-09-21
Fragile X syndrome (FXS) is caused by an expanded CGG repeat (> 200 repeats) in the 5' untranslated portion of the fragile mental retardation 1 gene (FMR1), leading to deficiency or absence of the FMR1 protein (FMRP). FMRP is an RNA carrier protein that controls the translation of several other genes that regulate synaptic development and plasticity. Autism occurs in approximately 30% of FXS cases, and pervasive developmental disorder, not otherwise specified (PDD-NOS) occurs in an additional 30% of cases. Premutation repeat expansions (55 to 200 CGG repeats) may also give rise to autism spectrum disorders (ASD), including both autism and PDD-NOS, through a different molecular mechanism that involves a direct toxic effect of the expanded CGG repeat FMR1 mRNA. RNA toxicity can also lead to aging effects including tremor, ataxia and cognitive decline, termed fragile X-associated tremor ataxia syndrome (FXTAS), in premutation carriers in late life. In studies of mice bearing premutation expansions, there is evidence of early postnatal neuronal cell toxicity, presenting as reduced cell longevity, decreased dendritic arborization and altered synaptic morphology. There is also evidence of mitochondrial dysfunction in premutation carriers. Many of the problems with cellular dysregulation in both premutation and full mutation neurons also parallel the cellular abnormalities that have been documented in autism without fragile X mutations. Research regarding dysregulation of neurotransmitter systems in FXS, including the metabotropic glutamate receptor (mGluR)1/5 pathway and γ aminobutyric acid (GABA)A pathways, have led to new targeted treatments for FXS. Preliminary evidence suggests that these new targeted treatments will also be beneficial in non-fragile X forms of autism.
Wirojanan, Juthamas; Jacquemont, Sebastien; Diaz, Rafael; Bacalman, Susan; Anders, Thomas F.; Hagerman, Randi J.; Goodlin-Jones, Beth L.
2009-01-01
Study Objective: To determine the efficacy of melatonin on sleep problems in children with autistic spectrum disorder (ASD) and fragile X syndrome (FXS). Methods: A 4-week, randomized, double blind, placebo-controlled, crossover design was conducted following a 1-week baseline period. Either melatonin, 3 mg, or placebo was given to participants for 2 weeks and then alternated for another 2 weeks. Sleep variables, including sleep duration, sleep-onset time, sleep-onset latency time, and the number of night awakenings, were recorded using an Actiwatch and from sleep diaries completed by parents. All participants had been thoroughly assessed for ASD and also had DNA testing for the diagnosis of FXS. Results: Data were successfully obtained from the 12 of 18 subjects who completed the study (11 males, age range 2 to 15.25 years, mean 5.47, SD 3.6). Five participants met diagnostic criteria for ASD, 3 for FXS alone, 3 for FXS and ASD, and 1 for fragile X premutation. Eight out of 12 had melatonin first. The conclusions from a nonparametric repeated-measures technique indicate that mean night sleep duration was longer on melatonin than placebo by 21 minutes (p = .02), mean sleep-onset latency was shorter by 28 minutes (p = .0001), and mean sleep-onset time was earlier by 42 minutes (p = .02). Conclusion: The results of this study support the efficacy and tolerability of melatonin treatment for sleep problems in children with ASD and FXS. Citation: Wirojanan J; Jacquemont S; Diaz R; Bacalman S; Anders TF; Hagerman RJ; Goodlin-Jones BL. The Efficacy of Melatonin for Sleep Problems in Children with Autism, Fragile X Syndrome, or Autism and Fragile X Syndrome. J Clin Sleep Med 2009;5(2):145-150. PMID:19968048
Lifetime prevalence of mood and anxiety disorders in fragile X premutation carriers.
Bourgeois, James A; Seritan, Andreea L; Casillas, E Melina; Hessl, David; Schneider, Andrea; Yang, Ying; Kaur, Inderjeet; Cogswell, Jennifer B; Nguyen, Danh V; Hagerman, Randi J
2011-02-01
The authors studied the lifetime prevalence of DSM-IV-TR psychiatric disorders in a population of adults with the fragile X premutation. The Structured Clinical Interview for DSM-IV was conducted, from 2007-2008, in 85 individuals with the fragile X premutation, 47 with the fragile X-associated tremor/ataxia syndrome (FXTAS; 33 male, 14 female; mean age = 66 years) and 38 without FXTAS (16 male, 22 female; mean age = 52 years). Lifetime prevalence for mood and anxiety disorders among carriers with and without FXTAS was compared to available age-specific population estimates from the National Comorbidity Survey Replication (NCS-R). Among participants with FXTAS, 30 (65%) met lifetime DSM-IV-TR criteria for a mood disorder; 24 (52%) met lifetime DSM-IV-TR criteria for an anxiety disorder. Among the non-FXTAS participants, there were 15 instances of lifetime mood disorder (42%) and 18 of lifetime anxiety disorder (47%). When compared to age-specific NCS-R data, the lifetime prevalences of any mood disorder (P < .0001), major depressive disorder (P < .0001), any anxiety disorder (P < .0001), panic disorder (P = .006), specific phobia (P = .0003), and posttraumatic stress disorder (P = .004) were significantly higher in participants with FXTAS. The lifetime rates of social phobia in individuals with the premutation without FXTAS were significantly higher than NCS-R data (P = .001). This sample of carriers of the fragile X premutation had a notably high lifetime risk of mood and anxiety disorders. Mood and anxiety disorders may be part of the clinical phenotype of the fragile X premutation conditions, especially in carriers with FXTAS. Clinicians encountering these patients are advised to consider FXTAS as a neuropsychiatric syndrome as well as a neurologic disorder. © Copyright 2011 Physicians Postgraduate Press, Inc.
Martinez-Laguna, Daniel; Soria-Castro, Alberto; Carbonell-Abella, Cristina; Orozco-López, Pilar; Estrada-Laza, Pilar; Nogues, Xavier; Díez-Perez, Adolfo; Prieto-Alhambra, Daniel
2017-11-28
Electronic medical records databases use pre-specified lists of diagnostic codes to identify fractures. These codes, however, are not specific enough to disentangle traumatic from fragility-related fractures. We report on the proportion of fragility fractures identified in a random sample of coded fractures in SIDIAP. Patients≥50 years old with any fracture recorded in 2012 (as per pre-specified ICD-10 codes) and alive at the time of recruitment were eligible for this retrospective observational study in 6 primary care centres contributing to the SIDIAP database (www.sidiap.org). Those with previous fracture/s, non-responders, and those with dementia or a serious psychiatric disease were excluded. Data on fracture type (traumatic vs fragility), skeletal site, and basic patient characteristics were collected. Of 491/616 (79.7%) patients with a registered fracture in 2012 who were contacted, 331 (349 fractures) were included. The most common fractures were forearm (82), ribs (38), and humerus (32), and 225/349 (64.5%) were fragility fractures, with higher proportions for classic osteoporotic sites: hip, 91.7%; spine, 87.7%; and major fractures, 80.5%. This proportion was higher in women, the elderly, and patients with a previously coded diagnosis of osteoporosis. More than 4 in 5 major fractures recorded in SIDIAP are due to fragility (non-traumatic), with higher proportions for hip (92%) and vertebral (88%) fracture, and a lower proportion for fractures other than major ones. Our data support the validity of SIDIAP for the study of the epidemiology of osteoporotic fractures. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.
Paschalis, Eleftherios P; Gamsjaeger, Sonja; Dempster, David; Jorgetti, Vanda; Borba, Victoria; Boguszewski, Cesar L; Klaushofer, Klaus; Moreira, Carolina A
2017-01-01
Chronic obstructive pulmonary disease (COPD) is associated with low areal bone mineral density (aBMD) by dual-energy X-ray absorptiometry (DXA) and altered microstructure by bone histomorphometry and micro-computed tomography. Nevertheless, not all COPD patients sustain fragility fractures. In the present study, we used Raman microspectroscopic analysis to determine bone compositional properties at actively forming trabecular surfaces (based on double fluorescent labels) in iliac crest biopsies from 19 postmenopausal COPD patients (aged 62.1 ± 7.3 years). Additionally, we analyzed trabecular geometrical centers, representing tissue much older than the forming surfaces. Eight of the patients had sustained fragility fractures, and 13 had received treatment with inhaled glucocorticoids. None of the patients had taken oral glucocorticoids. The monitored parameters were mineral/matrix ratio (MM), nanoporosity, and relative glycosaminoglycan (GAG), lipid, and pyridinoline contents (PYD). There were no significant differences between the glucocorticoid-treated patients and those who did not receive any. On the other hand, COPD patients sustaining fragility fractures had significantly lower nanoporosity and higher MM and PYD values compared with COPD patients without fragility fractures. To the best of our knowledge, this is the first study to discriminate between fracture and non-fracture COPD patients based on differences in the material properties of bone matrix. Given that these bone material compositional differences are evident close to the cement line (a major bone interface), they may contribute to the inferior bone toughness and coupled with the lower lumbar spine bone mineral density values result in the fragility fractures prevalent in these patients. © 2016 American Society for Bone and Mineral Research. © 2016 American Society for Bone and Mineral Research.
Fragility non-hip fracture patients are at risk.
Gosch, M; Druml, T; Nicholas, J A; Hoffmann-Weltin, Y; Roth, T; Zegg, M; Blauth, M; Kammerlander, C
2015-01-01
Fragility fractures are a growing worldwide health care problem. Hip fractures have been clearly associated with poor outcomes. Fragility fractures of other bones are common reasons for hospital admission and short-term disability, but specific long-term outcome studies of non-hip fragility fractures are rare. The aim of our trial was to evaluate the 1-year outcomes of non-hip fragility fracture patients. This study is a retrospective cohort review of 307 consecutive older inpatient non-hip fracture patients. Patient data for analysis included fracture location, comorbidity prevalence, pre-fracture functional status, osteoporosis treatments and sociodemographic characteristics. The main outcomes evaluated were 1-year mortality and post-fracture functional status. As compared to the expected mortality, the observed 1-year mortality was increased in the study group (17.6 vs. 12.2 %, P = 0.005). After logistic regression, three variables remained as independent risk factors for 1-year mortality among non-hip fracture patients: malnutrition (OR 3.3, CI 1.5-7.1), Charlson comorbidity index (CCI) (OR 1.3, CI 1.1-1.5) and the Parker Mobility Score (PMS) (OR 0.85, CI 0.74-0.98). CCI and PMS were independent risk factors for a high grade of dependency after 1 year. Management of osteoporosis did not significantly improve after hospitalization due to a non-hip fragility fracture. The outcomes of older non-hip fracture patients are comparable to the poor outcomes of older hip fracture patients, and appear to be primarily related to comorbidities, pre-fracture function and nutritional status. The low rate of patients on osteoporosis medications likely reflects the insufficient recognition of the importance of osteoporosis assessment and treatment in non-hip fracture patients. Increased clinical and academic attention to non-hip fracture patients is needed.
Spectrometer capillary vessel and method of making same
Linehan, J.C.; Yonker, C.R.; Zemanian, T.S.; Franz, J.A.
1995-11-21
The present invention is an arrangement of a glass capillary tube for use in spectroscopy. In particular, the invention is a capillary arranged in a manner permitting a plurality or multiplicity of passes of a sample material through a spectroscopic measurement zone. In a preferred embodiment, the multi-pass capillary is insertable within a standard NMR sample tube. The present invention further includes a method of making the multi-pass capillary tube and an apparatus for spinning the tube. 13 figs.
Capillaries for use in a multiplexed capillary electrophoresis system
Yeung, Edward S.; Chang, Huan-Tsang; Fung, Eliza N.
1997-12-09
The invention provides a side-entry optical excitation geometry for use in a multiplexed capillary electrophoresis system. A charge-injection device is optically coupled to capillaries in the array such that the interior of a capillary is imaged onto only one pixel. In Sanger-type 4-label DNA sequencing reactions, nucleotide identification ("base calling") is improved by using two long-pass filters to split fluorescence emission into two emission channels. A binary poly(ethyleneoxide) matrix is used in the electrophoretic separations.
Capillaries for use in a multiplexed capillary electrophoresis system
Yeung, E.S.; Chang, H.T.; Fung, E.N.
1997-12-09
The invention provides a side-entry optical excitation geometry for use in a multiplexed capillary electrophoresis system. A charge-injection device is optically coupled to capillaries in the array such that the interior of a capillary is imaged onto only one pixel. In Sanger-type 4-label DNA sequencing reactions, nucleotide identification (``base calling``) is improved by using two long-pass filters to split fluorescence emission into two emission channels. A binary poly(ethyleneoxide) matrix is used in the electrophoretic separations. 19 figs.
Capillary-Condenser-Pumped Heat-Transfer Loop
NASA Technical Reports Server (NTRS)
Silverstein, Calvin C.
1989-01-01
Heat being transferred supplies operating power. Capillary-condenser-pumped heat-transfer loop similar to heat pipe and to capillary-evaporator-pumped heat-transfer loop in that heat-transfer fluid pumped by evaporation and condensation of fluid at heat source and sink, respectively. Capillary condenser pump combined with capillary evaporator pump to form heat exchanger circulating heat-transfer fluids in both loops. Transport of heat more nearly isothermal. Thermal stress in loop reduced, and less external surface area needed in condenser section for rejection of heat to heat sink.
Social Approach and Emotion Recognition in Fragile X Syndrome
ERIC Educational Resources Information Center
Williams, Tracey A.; Porter, Melanie A.; Langdon, Robyn
2014-01-01
Evidence is emerging that individuals with Fragile X syndrome (FXS) display emotion recognition deficits, which may contribute to their significant social difficulties. The current study investigated the emotion recognition abilities, and social approachability judgments, of FXS individuals when processing emotional stimuli. Relative to…
21 CFR 864.6600 - Osmotic fragility test.
Code of Federal Regulations, 2011 CFR
2011-04-01
... test. (a) Identification. An osmotic fragility test is a device used to determine the resistance of red blood cells to hemolysis (destruction) in varying concentrations of hypotonic saline solutions. (b) Classification. Class I (general controls). This device is exempt from the premarket notification procedures in...
21 CFR 864.6600 - Osmotic fragility test.
Code of Federal Regulations, 2012 CFR
2012-04-01
... test. (a) Identification. An osmotic fragility test is a device used to determine the resistance of red blood cells to hemolysis (destruction) in varying concentrations of hypotonic saline solutions. (b) Classification. Class I (general controls). This device is exempt from the premarket notification procedures in...
21 CFR 864.6600 - Osmotic fragility test.
Code of Federal Regulations, 2014 CFR
2014-04-01
... test. (a) Identification. An osmotic fragility test is a device used to determine the resistance of red blood cells to hemolysis (destruction) in varying concentrations of hypotonic saline solutions. (b) Classification. Class I (general controls). This device is exempt from the premarket notification procedures in...
21 CFR 864.6600 - Osmotic fragility test.
Code of Federal Regulations, 2013 CFR
2013-04-01
... test. (a) Identification. An osmotic fragility test is a device used to determine the resistance of red blood cells to hemolysis (destruction) in varying concentrations of hypotonic saline solutions. (b) Classification. Class I (general controls). This device is exempt from the premarket notification procedures in...
21 CFR 864.6600 - Osmotic fragility test.
Code of Federal Regulations, 2010 CFR
2010-04-01
... test. (a) Identification. An osmotic fragility test is a device used to determine the resistance of red blood cells to hemolysis (destruction) in varying concentrations of hypotonic saline solutions. (b) Classification. Class I (general controls). This device is exempt from the premarket notification procedures in...
Salmon theology: Return to traditional reasoning
Joseph Clair
2007-01-01
When beauty and utility are divorced in the loss of wonder, beauty begins to perish. Salmon go extinct. The fragility of beauty is the fragility of wilderness. It does not perish due to weakness but from the generosity and vulnerability that are bound up with its usefulness.
Thermal and fragility studies on microwave synthesized K2O-B2O3-V2O5 glasses
NASA Astrophysics Data System (ADS)
Harikamalasree, Reddy, M. Sudhakara; Viswanatha, R.; Reddy, C. Narayana
2016-05-01
Glasses with composition xK2O-60B2O3-(40-x) V2O5 (15 ≤ x ≤ 39 mol %) was prepared by an energy efficient microwave method. The heat capacity change (ΔCp) at glass transition (Tg), width of glass transition (ΔTg), heat capacities in the glassy (Cpg) and liquid (Cpl) state for the investigated glasses were extracted from Modulated Differential Scanning Calorimetry (MDSC) thermograms. The width of glass transition is less than 30°C, indicating that these glasses belongs to fragile category. Fragility functions [NBO]/(Vm3Tg) and (ΔCp/Cpl)increases with increasing modifier oxide concentration. Increase in fragility is attributed to the increasing coordination of boron. Further, addition of K2O creates NBOs and the flow mechanism involves bond switching between BOs and NBOs. Physical properties exhibit compositional dependence and these properties increase with increasing K2O concentration. The observed variations are qualitatively analyzed.
Cribb, Peter H.; Olfert, Ernest A.; Reynolds, F. Barry
1986-01-01
A Doberman-German Shepherd cross-bred male dog, previously diagnosed as malignant hyperthermia susceptible, was mated to an unrelated nonsusceptible German Shepherd cross-bred female. The resultant litter was subjected to hematological, biochemical and erythrocyte osmotic fragility testing in an endeavor to predict the susceptibility of individuals to malignant hyperthermia. Laboratory evaluations were repeated at one year of age and the litter subjected to the halothane challenge test. No significant difference in erythrocyte osmotic fragility was found between malignant hyperthermia susceptible and nonsusceptible siblings at six weeks or at one year of age. Erythrocyte osmotic fragility, in both malignant hyperthermia susceptible and nonsusceptible animals, increased between six weeks and one year of age. Dantrolene sodium was an effective treatment for malignant hyperthermia in the dog when administered early in an episode and in adequate dosage. The initial sign of a malignant hyperthermia episode was a very rapid increase in end tidal partial pressure of carbon dioxide. This finding reinforces the value of capnographic monitoring in anesthesia. PMID:17422730
Significant difference in the dynamics between strong and fragile glass formers.
Furukawa, Akira; Tanaka, Hajime
2016-11-01
Glass-forming liquids are often classified into strong glass formers with nearly Arrhenius behavior and fragile ones with super-Arrhenius behavior. We reveal a significant difference in the dynamics between these two types of glass formers through molecular dynamics simulations: In strong glass formers, the relaxation dynamics of density fluctuations is nondiffusive, whereas in fragile glass formers it exhibits diffusive behavior. We demonstrate that this distinction is a direct consequence of the fundamental difference in the underlying elementary relaxation process between these two dynamical classes of glass formers. For fragile glass formers, a density-exchange process proceeds the density relaxation, which takes place locally at the particle level in normal states but is increasingly cooperative and nonlocal as the temperature is lowered in supercooled states. On the other hand, in strong glass formers, such an exchange process is not necessary for density relaxation due to the presence of other local relaxation channels. Our finding provides a novel insight into Angell's classification scheme from a hydrodynamic perspective.
A Guide to Improving the Care of Patients with Fragility Fractures, Edition 2
Mears, Simon C.
2015-01-01
Over the past 4 decades, much has been learned about the pathophysiology and treatment of osteoporosis, the prevention of fragility fractures, and the perioperative management of patients who have these debilitating injuries. However, the volume of published literature on this topic is staggering and far too voluminous for any clinician to review and synthesize by him or herself. This manuscript thoroughly summarizes the latest research on fragility fractures and provides the reader with valuable strategies to optimize the prevention and management of these devastating injuries. The information contained in this article will prove invaluable to any health care provider or health system administrator who is involved in the prevention and management of fragility hip fractures. As providers begin to gain a better understanding of the principles espoused in this article, it is our hope that they will be able to use this information to optimize the care they provide for elderly patients who are at risk of or who have osteoporotic fractures. PMID:26246957
Fragile X Syndrome and Targeted Treatment Trials
Lauterborn, Julie; Au, Jacky; Berry-Kravis, Elizabeth
2014-01-01
Work in recent years has revealed an abundance of possible new treatment targets for fragile X syndrome (FXS). The use of animal models, including the fragile X knockout mouse which manifests a phenotype very similar to FXS in humans, has resulted in great strides in this direction of research. The lack of Fragile X Mental Retardation Protein (FMRP) in FXS causes dysregulation and usually overexpression of a number of its target genes, which can cause imbalances of neurotransmission and deficits in synaptic plasticity. The use of metabotropic glutamate receptor (mGluR) blockers and gamma amino-butyric acid (GABA) agonists have been shown to be efficacious in reversing cellular and behavioral phenotypes, and restoring proper brain connectivity in the mouse and fly models. Proposed new pharmacological treatments and educational interventions are discussed in this chapter. In combination, these various targeted treatments show promising preliminary results in mitigating or even reversing the neurobiological abnormalities caused by loss of FMRP, with possible translational applications to other neurodevelopmental disorders including autism. PMID:22009360
Molecular Advances Leading to Treatment Implications for Fragile X Premutation Carriers
Polussa, Jonathan; Schneider, Andrea; Hagerman, Randi
2014-01-01
Fragile X syndrome (FXS) is the most common single gene cause of intellectual disability and it is characterized by a CGG expansion of more than 200 repeats in the FMR1 gene, leading to methylation of the promoter and gene silencing. The fragile X premutation, characterized by a 55 to 200 CGG repeat expansion, causes health problems and developmental difficulties in some, but not all, carriers. The premutation causes primary ovarian insufficiency in approximately 20% of females, psychiatric problems (including depression and/or anxiety) in approximately 50% of carriers and a neurodegenerative disorder, the fragile X-associated tremor ataxia syndrome (FXTAS), in approximately 40% of males and 16% of females later in life. Recent clinical studies in premutation carriers have expanded the health problems that may be seen. Advances in the molecular pathogenesis of the premutation have shown significant mitochondrial dysfunction and oxidative stress in neurons which may be amenable to treatment. Here we review the clinical problems of carriers and treatment recommendations. PMID:25436181
Fragile X syndrome and targeted treatment trials.
Hagerman, Randi; Lauterborn, Julie; Au, Jacky; Berry-Kravis, Elizabeth
2012-01-01
Work in recent years has revealed an abundance of possible new treatment targets for fragile X syndrome (FXS). The use of animal models, including the fragile X knockout mouse which manifests a phenotype very similar to FXS in humans, has resulted in great strides in this direction of research. The lack of Fragile X Mental Retardation Protein (FMRP) in FXS causes dysregulation and usually overexpression of a number of its target genes, which can cause imbalances of neurotransmission and deficits in synaptic plasticity. The use of metabotropic glutamate receptor (mGluR) blockers and gamma amino-butyric acid (GABA) agonists have been shown to be efficacious in reversing cellular and behavioral phenotypes, and restoring proper brain connectivity in the mouse and fly models. Proposed new pharmacological treatments and educational interventions are discussed in this chapter. In combination, these various targeted treatments show promising preliminary results in mitigating or even reversing the neurobiological abnormalities caused by loss of FMRP, with possible translational applications to other neurodevelopmental disorders including autism.
Robust-yet-fragile nature of interdependent networks
NASA Astrophysics Data System (ADS)
Tan, Fei; Xia, Yongxiang; Wei, Zhi
2015-05-01
Interdependent networks have been shown to be extremely vulnerable based on the percolation model. Parshani et al. [Europhys. Lett. 92, 68002 (2010), 10.1209/0295-5075/92/68002] further indicated that the more intersimilar networks are, the more robust they are to random failures. When traffic load is considered, how do the coupling patterns impact cascading failures in interdependent networks? This question has been largely unexplored until now. In this paper, we address this question by investigating the robustness of interdependent Erdös-Rényi random graphs and Barabási-Albert scale-free networks under either random failures or intentional attacks. It is found that interdependent Erdös-Rényi random graphs are robust yet fragile under either random failures or intentional attacks. Interdependent Barabási-Albert scale-free networks, however, are only robust yet fragile under random failures but fragile under intentional attacks. We further analyze the interdependent communication network and power grid and achieve similar results. These results advance our understanding of how interdependency shapes network robustness.
Pannunzio, Nicholas R; Lieber, Michael R
2017-12-07
DNA double-strand breaks (DSBs) occurring within fragile zones of less than 200 base pairs account for the formation of the most common human chromosomal translocations in lymphoid malignancies, yet the mechanism of how breaks occur remains unknown. Here, we have transferred human fragile zones into S. cerevisiae in the context of a genetic assay to understand the mechanism leading to DSBs at these sites. Our findings indicate that a combination of factors is required to sensitize these regions. Foremost, DNA strand separation by transcription or increased torsional stress can expose these DNA regions to damage from either the expression of human AID or increased oxidative stress. This damage causes DNA lesions that, if not repaired quickly, are prone to nuclease cleavage, resulting in DSBs. Our results provide mechanistic insight into why human neoplastic translocation fragile DNA sequences are more prone to enzymes or agents that cause longer-lived DNA lesions. Copyright © 2017 Elsevier Inc. All rights reserved.
Lee, Hye Young; Jan, Lily Yeh
2012-10-01
Fragile X syndrome (FXS) is a common form of mental disability and one of the known causes of autism. The mutation responsible for FXS is a large expansion of the trinucleotide CGG repeats that leads to DNA methylation of the fragile X mental retardation gene 1 (FMR1) and transcriptional silencing, resulting in the absence of fragile X mental retardation protein (FMRP), an mRNA binding protein. Although it is widely known that FMRP is critical for metabotropic glutamate receptor (mGluR)-dependent long-term depression (LTD), which has provided a general theme for developing pharmacological drugs for FXS, specific downstream targets of FMRP may also be of therapeutic value. Since alterations in potassium channel expression level or activity could underlie neuronal network defects in FXS, here we describe recent findings on how these channels might be altered in mouse models of FXS and the possible therapeutic avenues for treating FXS. Copyright © 2012 Elsevier Ltd. All rights reserved.
RTEL1 Inhibits Trinucleotide Repeat Expansions and Fragility
Frizzell, Aisling; Nguyen, Jennifer H.G.; Petalcorin, Mark I.R.; Turner, Katherine D.; Boulton, Simon J.; Freudenreich, Catherine H.; Lahue, Robert S.
2018-01-01
SUMMARY Human RTEL1 is an essential, multifunctional helicase that maintains telomeres, regulates homologous recombination, and helps prevent bone marrow failure. Here, we show that RTEL1 also blocks trinucleotide repeat expansions, the causal mutation for 17 neurological diseases. Increased expansion frequencies of (CTG·CAG) repeats occurred in human cells following knockdown of RTEL1, but not the alternative helicase Fbh1, and purified RTEL1 efficiently unwound triplet repeat hairpins in vitro. The expansion-blocking activity of RTEL1 also required Rad18 and HLTF, homologs of yeast Rad18 and Rad5. These findings are reminiscent of budding yeast Srs2, which inhibits expansions, unwinds hairpins, and prevents triplet-repeat-induced chromosome fragility. Accordingly, we found expansions and fragility were suppressed in yeast srs2 mutants expressing RTEL1, but not Fbh1. We propose that RTEL1 serves as a human analog of Srs2 to inhibit (CTG·CAG) repeat expansions and fragility, likely by unwinding problematic hairpins. PMID:24561255
RTEL1 inhibits trinucleotide repeat expansions and fragility.
Frizzell, Aisling; Nguyen, Jennifer H G; Petalcorin, Mark I R; Turner, Katherine D; Boulton, Simon J; Freudenreich, Catherine H; Lahue, Robert S
2014-03-13
Human RTEL1 is an essential, multifunctional helicase that maintains telomeres, regulates homologous recombination, and helps prevent bone marrow failure. Here, we show that RTEL1 also blocks trinucleotide repeat expansions, the causal mutation for 17 neurological diseases. Increased expansion frequencies of (CTG⋅CAG) repeats occurred in human cells following knockdown of RTEL1, but not the alternative helicase Fbh1, and purified RTEL1 efficiently unwound triplet repeat hairpins in vitro. The expansion-blocking activity of RTEL1 also required Rad18 and HLTF, homologs of yeast Rad18 and Rad5. These findings are reminiscent of budding yeast Srs2, which inhibits expansions, unwinds hairpins, and prevents triplet-repeat-induced chromosome fragility. Accordingly, we found expansions and fragility were suppressed in yeast srs2 mutants expressing RTEL1, but not Fbh1. We propose that RTEL1 serves as a human analog of Srs2 to inhibit (CTG⋅CAG) repeat expansions and fragility, likely by unwinding problematic hairpins. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.
Molecular Abnormalities Underlying Bone Fragility in Chronic Kidney Disease
Iwasaki, Yoshiko; Kazama, Junichiro James
2017-01-01
Prevention of bone fractures is one goal of therapy for patients with chronic kidney disease-mineral and bone disorder (CKD-MBD), as indicated by the Kidney Disease: Improving Global Outcomes guidelines. CKD patients, including those on hemodialysis, are at higher risk for fractures and fracture-related death compared to people with normal kidney function. However, few clinicians focus on this issue as it is very difficult to estimate bone fragility. Additionally, uremia-related bone fragility has a more complicated pathological process compared to osteoporosis. There are many uremia-associated factors that contribute to bone fragility, including severe secondary hyperparathyroidism, skeletal resistance to parathyroid hormone, and bone mineralization disorders. Uremia also aggravates bone volume loss, disarranges microarchitecture, and increases the deterioration of material properties of bone through abnormal bone cells or excess oxidative stress. In this review, we outline the prevalence of fractures, the interaction of CKD-MBD with osteoporosis in CKD patients, and discuss possible factors that exacerbate the mechanical properties of bone. PMID:28421193
Light propagation in the micro-size capillary injected by high temperature liquid
NASA Astrophysics Data System (ADS)
Li, Yan-jun; Li, Edward; Xiao, Hai
2016-11-01
The high temperature liquid is injected into the micro-size capillary and its light propagation behavior is investigated. We focus on two different liquid pumping methods. The first method can pump the high temperature liquid tin into the micro-size capillary by using a high pressure difference system. After pumping, a single mode fiber (SMF) connected with the optical carrier based microwave interferometry (OCMI) system is used to measure different liquid tin levels in the micro-size capillary. The second method can pump the room temperature engine oil into the capillary by using a syringe pump. This method can avoid the air bubbles when the liquids are pumped into the capillary.
NASA Astrophysics Data System (ADS)
Schlicker, Lukas; Doran, Andrew; Schneppmüller, Peter; Gili, Albert; Czasny, Mathias; Penner, Simon; Gurlo, Aleksander
2018-03-01
This work describes a device for time-resolved synchrotron-based in situ and operando X-ray powder diffraction measurements at elevated temperatures under controllable gaseous environments. The respective gaseous sample environment is realized via a gas-tight capillary-in-capillary design, where the gas flow is achieved through an open-end 0.5 mm capillary located inside a 0.7 mm capillary filled with a sample powder. Thermal mass flow controllers provide appropriate gas flows and computer-controlled on-the-fly gas mixing capabilities. The capillary system is centered inside an infrared heated, proportional integral differential-controlled capillary furnace allowing access to temperatures up to 1000 °C.
Paper Capillary Enables Effective Sampling for Microfluidic Paper Analytical Devices.
Shangguan, Jin-Wen; Liu, Yu; Wang, Sha; Hou, Yun-Xuan; Xu, Bi-Yi; Xu, Jing-Juan; Chen, Hong-Yuan
2018-06-06
Paper capillary is introduced to enable effective sampling on microfluidic paper analytical devices. By coupling mac-roscale capillary force of paper capillary and microscale capillary forces of native paper, fluid transport can be flexibly tailored with proper design. Subsequently, a hybrid-fluid-mode paper capillary device was proposed, which enables fast and reliable sampling in an arrayed form, with less surface adsorption and bias for different components. The resulting device thus well supports high throughput, quantitative, and repeatable assays all by hands operation. With all these merits, multiplex analysis of ions, proteins, and microbe have all been realized on this platform, which has paved the way to level-up analysis on μPADs.
Wang, Siming; Su, Ping; Hongjun, E; Yang, Yi
2010-10-15
Polyamidoamine dendrimer (PAMAM) is one of a number of dendritic polymers with precise molecular structure, highly geometric symmetry, and a large number of terminal groups. In this study, different generations of PAMAM (G0-G4) were introduced onto the inner wall of fused-silica capillaries by microwave irradiation and a new type of glucose oxidase (GOx) capillary enzyme microreactor was developed based on enzyme immobilization in the prepared PAMAM-grafted fused-silica capillaries. The optimal enzymolysis conditions for beta-d-glucose in the microreactor were evaluated by capillary zone electrophoresis. In addition, the enzymolysis efficiencies of different generations of PAMAM-GOx capillary enzyme microreactor were compared. The results indicate that enzymolysis efficiency increased with increasing generations of PAMAM. The experimental results provide the possibility for the development and application of an online immobilized capillary enzyme microreactor. Crown Copyright 2010. Published by Elsevier Inc. All rights reserved.
Wojcik, Roza; Vannatta, Michael
2010-01-01
Diagonal capillary electrophoresis is a form of two-dimensional capillary electrophoresis that employs identical separation modes in each dimension. The distal end of the first capillary incorporates an enzyme-based microreactor. Analytes that are not modified by the reactor will have identical migration times in the two capillaries and will generate spots that fall on the diagonal in a reconstructed two-dimensional electropherogram. Analytes that undergo enzymatic modification in the reactor will have a different migration time in the second capillary and will generate spots that fall off the diagonal in the electropherogram. We demonstrate the system with immobilized alkaline phosphatase to monitor the phosphorylation status of a mixture of peptides. This enzyme-based diagonal capillary electrophoresis assay appears to be generalizable; any post-translational modification can be detected as long as an immobilized enzyme is available that reacts with the modification under electrophoretic conditions. PMID:20099889
Khairallah, Moncef; Kahloun, Rim; Gargouri, Salma; Jelliti, Bechir; Sellami, Dorra; Ben Yahia, Salim; Feki, Jamel
2017-08-01
A 65-year-old man with diabetes and a history of fever of unknown origin 2 weeks earlier complained of sudden decreased vision in the left eye. The patient was diagnosed with bilateral West Nile virus (WNV) chorioretinitis associated with occlusive retinal vasculitis in the left eye. Swept-source optical coherence tomography angiography (SS-OCTA) of the left eye showed extensive, well-delineated, hypointense non-perfusion areas and perifoveal capillary arcade disruption in the superficial capillary plexus, as well as larger non-perfusion areas, capillary rarefaction, and diffuse capillary network attenuation and disorganization in the deep capillary plexus. OCTA may be a valuable tool for noninvasively assessing occlusive retinal vasculitis associated with WNV infection. It allows an accurate detection and precise delineation of areas of retinal capillary nonperfusion in both the superficial and deep capillary plexuses. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:672-675.]. Copyright 2017, SLACK Incorporated.
Alarcon-Martinez, Luis; Yilmaz-Ozcan, Sinem; Yemisci, Muge; Schallek, Jesse; Kılıç, Kıvılcım; Can, Alp; Di Polo, Adriana; Dalkara, Turgay
2018-03-21
Recent evidence suggests that capillary pericytes are contractile and play a crucial role in the regulation of microcirculation. However, failure to detect components of the contractile apparatus in capillary pericytes, most notably α-smooth muscle actin (α-SMA), has questioned these findings. Using strategies that allow rapid filamentous-actin (F-actin) fixation (i.e. snap freeze fixation with methanol at -20°C) or prevent F-actin depolymerization (i.e. with F-actin stabilizing agents), we demonstrate that pericytes on mouse retinal capillaries, including those in intermediate and deeper plexus, express α-SMA. Junctional pericytes were more frequently α-SMA-positive relative to pericytes on linear capillary segments. Intravitreal administration of short interfering RNA (α-SMA-siRNA) suppressed α-SMA expression preferentially in high order branch capillary pericytes, confirming the existence of a smaller pool of α-SMA in distal capillary pericytes that is quickly lost by depolymerization. We conclude that capillary pericytes do express α-SMA, which rapidly depolymerizes during tissue fixation thus evading detection by immunolabeling. © 2018, Alarcon-Martinez et al.
Modeling capillary bridge dynamics and crack healing between surfaces of nanoscale roughness
NASA Astrophysics Data System (ADS)
Soylemez, Emrecan; de Boer, Maarten P.
2017-12-01
Capillary bridge formation between adjacent surfaces in humid environments is a ubiquitous phenomenon. It strongly influences tribological performance with respect to adhesion, friction and wear. Only a few studies, however, assess effects due to capillary dynamics. Here we focus on how capillary bridge evolution influences crack healing rates. Experimental results indicated a logarithmic decrease in average crack healing velocity as the energy release rate increases. Our objective is to model that trend. We assume that capillary dynamics involve two mechanisms: capillary bridge growth and subsequently nucleation followed by growth. We show that by incorporating interface roughness details and the presence of an adsorbed water layer, the behavior of capillary force dynamics can be understood quantitatively. We identify three important regimes that control the healing process, namely bridge growth, combined bridge growth and nucleation, and finally bridge nucleation. To fully capture the results, however, the theoretical model for nucleation time required an empirical modification. Our model enables significant insight into capillary bridge dynamics, with a goal of attaining a predictive capability for this important microelectromechanical systems (MEMS) reliability failure mechanism.
NASA Astrophysics Data System (ADS)
Punia, Sanjeev Singh; Singh, Jagdev
2015-11-01
This paper presents an experimental investigation for the flow of liquefied petroleum gas (LPG) as a refrigerant inside an adiabatic helically coiled capillary tube in vapour compression refrigeration system. The effect of various geometric parameters and operating conditions like capillary tube inner diameter, length of capillary tube, coil diameter and different inlet subcoolings on the mass flow rate of LPG through the helical coiled capillary tube geometry has been investigated. It has been established that the coil diameter significantly influences the mass flow rate of LPG through the adiabatic helical capillary tube. It has been concluded that the effect of coiling of capillary tube reduces the mass flow rate by 5-12 % as compared to those of the straight capillary tube operating under similar conditions. The data obtained from the experiments are analyzed and a dimensionless correlation has been developed. The proposed correlation predicts that more than 90 % of experimental data which is in agreement with measured data in an error band of ±10 %.
Two classes of capillary optical fibers: refractive and photonic
NASA Astrophysics Data System (ADS)
Romaniuk, Ryszard S.
2008-11-01
This paper is a digest tutorial on some properties of capillary optical fibers (COF). Two basic types of capillary optical fibers are clearly distinguished. The classification is based on propagation mechanism of optical wave. The refractive, singlemode COF guides a dark hollow beam of light (DHB) with zero intensity on fiber axis. The photonic, singlemode COF carries nearly a perfect axial Gaussian beam with maximum intensity on fiber axis. A subject of the paper are these two basic kinds of capillary optical fibers of pure refractive and pure photonic mechanism of guided wave transmission. In a real capillary the wave may be transmitted by a mixed mechanism, refractive and photonic, with strong interaction of photonic and refractive guided wave modes. Refractive capillary optical fibers are used widely for photonic instrumentation applications, while photonic capillary optical fibers are considered for trunk optical communications. Replacement of classical, single mode, dispersion shifted, 1550nm optimized optical fibers for communications with photonic capillaries would potentially cause a next serious revolution in optical communications. The predictions say that such a revolution may happen within this decade. This dream is however not fulfilled yet. The paper compares guided modes in both kinds of optical fiber capillaries: refractive and photonic. The differences are emphasized indicating prospective application areas of these fibers.
Preserved Entropy, quantum criticality and fragile magnetism
NASA Astrophysics Data System (ADS)
Canfield, Paul
A large swath of strongly correlated electron systems can be associated with the phenomenon of preserved entropy and fragile magnetism. In this talk I will present our thoughts and plans for the discovery and development of lanthanide and transition metal based, strongly correlated systems that are revealed by suppressed, fragile magnetism or grow out of preserved entropy. This talk is based on work published in This work was supported by the U.S. Dept. of Energy, Basic Energy Science, Division of Materials Sciences and Engineering under Contract No. DE-AC02-07CH11358 as well as by the Gordon and Betty Moore Foundations EPiQS Initiative through Grant GBMF4411.
Structure and Liquid Fragility in Sodium Carbonate.
Wilson, Mark; Ribeiro, Mauro C C; Wilding, Martin C; Benmore, Chris; Weber, J K R; Alderman, Oliver; Tamalonis, Anthony; Parise, J B
2018-02-01
The relationship between local structure and dynamics is explored for molten sodium carbonate. A flexible fluctuating-charge model, which allows for changes in the shape and charge distribution of the carbonate molecular anion, is developed. The system shows the evolution of highly temperature-dependent complex low-dimensional structures which control the dynamics (and hence the liquid fragility). By varying the molecular anion charge distribution, the key interactions responsible for the formation of these structures can be identified and rationalized. An increase in the mean charge separation within the carbonate ions increases the connectivity of the emerging structures and leads to an increase in the system fragility.
Non-fragile multivariable PID controller design via system augmentation
NASA Astrophysics Data System (ADS)
Liu, Jinrong; Lam, James; Shen, Mouquan; Shu, Zhan
2017-07-01
In this paper, the issue of designing non-fragile H∞ multivariable proportional-integral-derivative (PID) controllers with derivative filters is investigated. In order to obtain the controller gains, the original system is associated with an extended system such that the PID controller design can be formulated as a static output-feedback control problem. By taking the system augmentation approach, the conditions with slack matrices for solving the non-fragile H∞ multivariable PID controller gains are established. Based on the results, linear matrix inequality -based iterative algorithms are provided to compute the controller gains. Simulations are conducted to verify the effectiveness of the proposed approaches.
Modeling oxygen transport in human placental terminal villi.
Gill, J S; Salafia, C M; Grebenkov, D; Vvedensky, D D
2011-12-21
Oxygen transport from maternal blood to fetal blood is a primary function of the placenta. Quantifying the effectiveness of this exchange remains key in identifying healthy placentas because of the great variability in capillary number, caliber and position within the villus-even in placentas deemed clinically "normal". By considering villous membrane to capillary membrane transport, stationary oxygen diffusion can be numerically solved in terminal villi represented by digital photomicrographs. We aim to provide a method to determine whether and if so to what extent diffusional screening may operate in placental villi. Segmented digital photomicrographs of terminal villi from the Pregnancy, Infection and Nutrition study in North Carolina 2002 are used as a geometric basis for solving the stationary diffusion equation. Constant maternal villous oxygen concentration and perfect fetal capillary membrane absorption are assumed. System efficiency is defined as the ratio of oxygen flux into a villus and the sum of the capillary areas contained within. Diffusion screening is quantified by comparing numerical and theoretical maximum oxygen fluxes. A strong link between various measures of villous oxygen transport efficiency and the number of capillaries within a villus is established. The strength of diffusional screening is also related to the number of capillaries within a villus. Our measures of diffusional efficiency are shown to decrease as a function of the number of capillaries per villus. This low efficiency, high capillary number relationship supports our hypothesis that diffusional screening is present in this system. Oxygen transport per capillary is reduced when multiple capillaries compete for diffusing oxygen. A complete picture of oxygen fluxes, capillary and villus areas is obtainable and presents an opportunity for future work. Copyright © 2011 Elsevier Ltd. All rights reserved.
Irradiation of orderly multiline spectra from linear plasma formed by vacuum discharge capillary
NASA Astrophysics Data System (ADS)
Sato, Eiichi; Hayasi, Yasuomi; Germer, Rudolf; Ojima, Hidenori; Takayama, Kazuyoshi; Ido, Hideaki
2005-03-01
The fundamental experiments for measuring soft x-ray characteristics from the vacuum capillary are described. These experiments are primarily performed in order to generate intense soft x rays. The generator consists of a high-voltage power supply, a polarity-inversion ignitron pulse generator, a turbomolecular pump, and a radiation tube with a capillary. A high-voltage condenser of 200 nF in the pulse generator is charged up to 20 kV by the power supply, and the electric charges in the condenser are discharged to the capillary in the tube after closing the ignitron. During the discharge, weakly ionized plasma forms on the inner and outer sides of a capillary. In the present work, the pump evacuates air from the tube with a pressure of about 1 mPa, and a demountable capillary was developed in order to measure x-ray spectra according to changes in the capillary length. In this capillary, the anode (target) and cathode elements can be changed corresponding to the objectives. The capillary diameter is 2.0 mm, and the length is adjusted from 1 to 50 mm. When a capillary with aluminum anode and cathode electrodes was employed, both the cathode voltage and the discharge current almost displayed damped oscillations. The peak values of the voltage and current increased when the charging voltage was increased, and their maximum values were -11.5 kV and 4.7 kA, respectively. The x-ray durations observed by a 1.6 μm aluminum filter were less than 30 μs. In the spectrum measurement, we observed orderly multi-line spectra. The line photon energies seldom varied according to changes in the condenser charging voltage and to changes in the electrode element. The line number decreased with corresponding decreases in the capillary length.
Jillani, Shehzada Muhammad Sajid; Alhooshani, Khalid
2018-03-30
Sol-gel urea functionalized-[bis(hydroxyethyl)amine] terminated polydimethylsiloxane coating was developed for capillary microextraction-high performance liquid chromatographic analysis from aqueous samples. A fused silica capillary is coated from the inside with surface bonded coating material and is created through in-situ sol-gel reaction. The urea-functionalized coating was immobilized to the inner surface of the capillary by the condensation reaction of silanol groups of capillary and sol-solution. The characterization of the coating material was successfully done by using X-ray photoelectron spectroscopy, thermogravimetric analysis, field emission scanning electron microscope, and energy dispersive X-ray spectrometer. To make a setup of online capillary microextraction-high performance liquid chromatography, the urea functionalized capillary was installed in the HPLC manual injection port. The analytes of interest were pre-concentrated in the coated sampling loop, desorbed by the mobile phase, chromatographically separated on C-18 column, and analyzed by UV detector. Sol-gel coated capillaries were used for online extraction and high-performance liquid chromatographic analysis of phenols, ketones, aldehydes, and polyaromatic hydrocarbons. This newly developed coating showed excellent extraction for a variety of analytes ranging from highly polar to non-polar in nature. The analysis using sol-gel coating showed excellent overall sensitivity in terms of lower detection limits (S/N = 3) for the analytes (0.10 ng mL -1 -14.29 ng mL -1 ) with acceptable reproducibility that is less than 12.0%RSD (n = 3). Moreover, the capillary to capillary reproducibility of the analysis was also tested by changing the capillary of the same size. This provided excellent%RSD of less than 10.0% (n = 3). Copyright © 2018 Elsevier B.V. All rights reserved.
A comparison of capillary hydraulic conductivities in postural and locomotor muscle.
McDonagh, P F; Gore, R W
1982-09-01
In a comparative skeletal muscle study Folkow and Halicka (Microvasc. Res. 1: 1-14, 1968) reported that the capillary filtration coefficient (CFC) of postural (red) muscle was two times the CFC of locomotor (white) muscle. It was concluded that the twofold difference in CFC was due solely to a difference in the perfused capillary surface areas (Sf) of red vs. white muscle. However, CFC is the product of capillary hydraulic conductivity (LP) and Sf. Hence their conclusion assumed that the average LP of red muscle capillaries is exactly equal to the average LP of white muscle capillaries. The following study was undertaken to test the validity of this assumption. The microocclusion procedures and analytical model described by Lee et al. (Circ. Res. 28: 358-370, 1971) and Gore [Am. J. Physiol. 242 (Heart Circ. Physiol. 11): H268-H287, 1982] were used to determine LP. Independent measurements of LP were recorded from single capillaries in red, anterior latissimus dorsi (ALD) and white, posterior latissimus dorsi (PLD) muscles of chickens anesthetized with L.A. Thesia. We found that the mean capillary hydraulic conductivity in postural muscle [(LP)ALD = 0.20 +/- 0.06 (SE) micrometers . s-1 . cmH2O-1 (n = 11)] was significantly different from the mean capillary hydraulic conductivity in locomotor muscle [(LP)PLD = 0.061 +/- 0.01 micrometers . s-1 . cmH2O-1 (n = 14)] (P less than 0.05). These results provide direct evidence that observed differences in red vs. white muscle CFC's may not be due solely to different perfused capillary surface areas but may also be due to differences in capillary hydraulic conductivity.
Balaratnasingam, Chandrakumar; An, Dong; Sakurada, Yoichi; Lee, Cecilia S; Lee, Aaron Y; McAllister, Ian L; Freund, K Bailey; Sarunic, Marinko; Yu, Dao-Yi
2018-05-01
To use the capillary-free zone along retinal arteries, a physiologic area of superficial avascularization, as an anatomic paradigm to investigate the reliability of optical coherence tomography angiography (OCTA) for visualizing the deep retinal circulation. Validity analysis and laboratory investigation. Five normal human donor eyes (mean age 69.8 years) were perfusion-labeled with endothelial antibodies and the capillary networks of the perifovea were visualized using confocal scanning laser microscopy. Regions of the capillary-free zone along the retinal artery were imaged using OCTA in 16 normal subjects (age range 24-51 years). Then, 3 × 3-mm scans were acquired using the RTVue XR Avanti (ver. 2016.1.0.26; Optovue, Inc, Fremont, California, USA), PLEX Elite 9000 (ver. 1.5.0.15909; Zeiss Meditec, Inc, Dublin, California, USA), Heidelberg Spectralis OCT2 (Family acquisition module 6.7.21.0; Heidelberg Engineering, Heidelberg, Germany), and DRI-OCT Triton (Ver. 1.1.1; Topcon Corp, Tokyo, Japan). Images of the superficial plexus, deep vascular plexus, and a slab containing all vascular plexuses were generated using manufacturer-recommended default settings. Comparisons between histology and OCTA were performed. Histologic analysis revealed that the capillary-free zone along the retinal artery was confined to the plane of the superficial capillary plexus and did not include the intermediate and deep capillary plexuses. Images derived from OCTA instruments demonstrated a prominent capillary-free zone along the retinal artery in slabs of the superficial plexus, deep plexus, and all capillary plexuses. The number of deep retinal capillaries seen in the capillary-free zone was significantly greater on histology than on OCTA (P < .001). Using the capillary-free zone as an anatomic paradigm, we show that the deep vascular beds of the retina are not completely visualized using OCTA. This may be a limitation of current OCTA techniques. Copyright © 2018 Elsevier Inc. All rights reserved.
Du, Haiqin; Zhang, Chong; Mao, Ke; Wang, Yanmei
2017-08-01
In this work, an antifouling capillary modified with star-shaped poly(2-methyl-2-oxazoline)-based copolymer was used to study the interaction between acetaminophen (APAP) and bovine serum albumin (BSA) by frontal analysis capillary electrophoresis (FACE). The star-shaped copolymer, poly(ethylene imine)-graft-poly(2-methyl-2-oxazoline) (PEI-g-PMOXA), was immobilized onto the fused-silica capillary inner wall via dopamine-assisted co-deposition strategy, yielding a PEI-g-PMOXA/polydopamine (PDA)-coated antifouling capillary, i.e., an antifouling capillary coated with the PEI-g-PMOXA/PDA co-deposited film. Electroosmotic flow (EOF) mobility of the PEI-g-PMOXA/PDA-coated capillary was almost zero in a wide pH range (3.0-10.0), while the EOF mobility of bare capillary was much larger and increased significantly with pH increasing. When the PEI-g-PMOXA/PDA-coated capillary was exploited to separate a protein mixture including cytochrome c, lysozyme, ribonuclease A and α-chymotrypsinogen A, the theoretical plate numbers were of five orders of magnitude which were about ten-fold higher over those obtained with bare capillary; in addition, the RSD values of migration time were mostly less than 0.7% (30 consecutive runs) which were much smaller than those of bare capillary (c.a. 5.7%). The protein-resistant PEI-g-PMOXA/PDA-coated capillary was then used to investigate the interaction between APAP and BSA by FACE, the binding constant and number of binding sites at 25°C and pH 7.4 (Tris/HCl buffer of 25mM) were 1.39×10 4 M -1 and 1.08, respectively, which were comparable to the results determined by fluorescence spectroscopic measurement (3.18×10 4 M -1 and 1.19, respectively). Copyright © 2017 Elsevier B.V. All rights reserved.
Shavit, Itai; Brant, Rollin; Nijssen-Jordan, Cheri; Galbraith, Roger; Johnson, David W
2006-12-01
Assessment of dehydration in young children currently depends on clinical judgment, which is relatively inaccurate. By using digital videography, we developed a way to assess capillary-refill time more objectively. Our goal was to determine whether digitally measured capillary-refill time assesses the presence of significant dehydration (> or = 5%) in young children with gastroenteritis more accurately than conventional capillary refill and overall clinical assessment. We prospectively enrolled children with gastroenteritis, 1 month to 5 years of age, who were evaluated in a tertiary-care pediatric emergency department and judged by a triage nurse to be at least mildly dehydrated. Before any treatment, we measured the weight and digitally measured capillary-refill time of these children. Pediatric emergency physicians determined capillary-refill time by using conventional methods and degree of dehydration by overall clinical assessment by using a 7-point Likert scale. Postillness weight gain was used to estimate fluid deficit; beginning 48 hours after assessment, children were reweighed every 24 hours until 2 sequential weights differed by no more than 2%. We compared the accuracy of digitally measured capillary-refill time with conventional capillary refill and overall clinical assessment by determining sensitivities, specificities, likelihood ratios, and area under the receiver operator characteristic curves. A total of 83 patients were enrolled and had complete follow-up; 13 of these patients had significant dehydration (> or = 5% of body weight). The area under the receiver operator characteristic curves for digitally measured capillary-refill time and overall clinical assessment relative to fluid deficit (< 5% vs > or = 5%) were 0.99 and 0.88, respectively. Positive likelihood ratios were 11.7 for digitally measured capillary-refill time, 4.5 for conventional capillary refill, and 4.1 for overall clinical assessment. Results of this prospective cohort study suggest that digitally measured capillary-refill time more accurately predicts significant dehydration (> or = 5%) in young children with gastroenteritis than overall clinical assessment.
Treatment of Fragile X Syndrome with a Neuroactive Steroid
2015-08-01
in the fragile X mouse model and the Drosophila (fruit fly) models of FXS that the GABAA system, including multiple receptors, is dramatically down... Drosophila (fruit fly) models of FXS that the GABAA system, including multiple receptors, is dramatically down-regulated. Ganaxolone is a drug that
Introduction--Understanding Education, Fragility and Conflict
ERIC Educational Resources Information Center
Buchert, Lene
2013-01-01
This Introduction discusses approaches to and perspectives on analyzing the complex relationship between education, fragility, and conflict and its underlying causes and dynamics. It argues for the need for contextual and time-bound multi-level analyses of interlinked societal dimensions in order to address the ultimate purposes of education…
Marriage and Fatherhood Programs
ERIC Educational Resources Information Center
Cowan, Phillip A.; Cowan, Carolyn Pape; Knox, Virginia
2010-01-01
To improve the quality and stability of couple and father-child relationships in fragile families, researchers are beginning to consider how to tailor existing couple-relationship and father-involvement interventions, which are now targeted on married couples, to the specific needs of unwed couples in fragile families. The goal, explain Philip…
Fragile X Syndrome--From Genes to Cognition
ERIC Educational Resources Information Center
Schneider, A.; Hagerman, R. J.; Hessl, D.
2009-01-01
Fragile X syndrome (FXS), a single gene disorder with an expanded CGG allele on the X chromosome, is the most common form of inherited cognitive impairment. The cognitive deficit ranges from mild learning disabilities to severe intellectual disability. The phenotype includes hyperactivity, short attention span, emotional problems including…
Intellectual Functioning in Fragile X Syndrome School Children.
ERIC Educational Resources Information Center
Bromham, Susan; Jupp, James
1991-01-01
Aspects of intellectual function were investigated in a school age sample of 17 Fragile X individuals, employing the Wechsler Intelligence Scale for Children (Revised). The general ability of the sample was substantially below normative average because of the significantly poorer performance by males than females. (Author/DB)
Parental Relationships in Fragile Families
ERIC Educational Resources Information Center
McLanahan, Sara; Beck, Audrey N.
2010-01-01
As nonmarital childbearing escalated in the United States over the past half century, fragile families--defined as unmarried couples with children--drew increased interest from researchers and policy makers. Sara McLanahan and Audrey Beck discuss four aspects of parental relationships in these families: the quality of parents' intimate…
Migration And Entrapment Of Mercury In The Subsurface
NASA Astrophysics Data System (ADS)
M, D.; Nambi, I. M.
2009-12-01
Elemental mercury is an immiscible liquid with high density and high surface tension. The movement of mercury in the saturated subsurface region is therefore considered a case of two phase flow involving mercury and water and is expected to be governed by gravity, viscous and capillary forces. Fundamental investigation into the migration and capillary entrapment of mercury in the subsurface was done by controlled laboratory capillary pressure saturation experiments using mercury and water as non wetting and wetting fluid respectively. Residual mercury saturation and van Genuchten’s capillary entrapment parameters were determined independently for different sizes of porous media. Based on the experimental data, theoretical investigations were done on the role of the three predominant forces and their influence on mercury migration and entrapment. The effects of fluid density and interfacial tension and the influence of Capillary and Bond number on mercury entrapment were analyzed with the help of similar capillary pressure - saturation experiments using Tetrachloroethylene (PCE)-water fluid pair. Mercury-water systems exhibited a low residual saturation of 0.02 and 0.07 as compared to 0.16 and 0.27 for PCE-water systems. Less residual mercury saturation, lack of apparent hysteresis in capillary pressure saturation curves and large variation in van Genuchten’s parameters 'α'(inverse of displacement pressure) and ‘n’ (pore size distribution index) for mercury-water systems compared to PCE-water systems were observed. These anomalies between the two systems elucidate that the capillary trapping is equally dependent on the fluid characteristics especially for high density immiscible fluids. Gravity force nevertheless a predominant controlling factor in the migration of highly dense mercury, is counteracted by not less trivial capillary force which was 1.22x104 times higher than gravity force. The capillary forces thus surmount the gravity forces and cause entrapment of mercury in the soil pores even in homogeneous porous medium system. Bond number (Bond number relates gravity and capillary forces) for mercury-water system was found to 2.5 times higher than PCE-water systems. Large density differences between mercury and water lead to high Bond number and thus less residual saturation. Capillary number (Capillary number relates viscous and capillary forces) was found to be less for mercury-water systems. Literature review unveils that low Capillary number does not influence non wetting residual saturation. But for high density mercury with natural infiltration, even low Capillary number influences residual saturation. With the alarming increase in number of mercury spill sites, results of this study showed a better understanding of the capillary entrapment phenomena and the extent of influence of each predominant force during displacement of highly dense mercury. The fundamental inputs to NAPL entrapment models were generated in this study for mercury for the first time. This data will be used to assess the distribution of mercury in contaminated sites and design suitable remedial alternatives.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Holden, J.J.A.; Julien-Inalsingh, C.; Wing, M.
Sib, twin, and family studies have shown that a genetic cause exists in many cases of autism, with a portion of cases associated with a fragile X chromosome. Three folate-sensitive fragile sites in the Xq27{r_arrow}Xq28 region have been cloned and found to have polymorphic trinucleotide repeats at the respective sites; these repeats are amplified and methylated in individuals who are positive for the different fragile sites. We have tested affected boys and their mothers from 19 families with two autistic/PDD boys for amplification and/or instability of the triplet repeats at these loci and concordance of inheritance of alleles by affectedmore » brothers. In all cases, the triplet repeat numbers were within the normal range, with no individuals having expanded or premutation-size alleles. For each locus, there was no evidence for an increased frequency of concordance, indicating that mutations within these genes are unlikely to be responsible for the autistic/PDD phenotypes in the affected boys. Thus, we think it is important to retest those autistic individuals who were cytogenetically positive for a fragile X chromosome, particularly cases where there is no family history of the fragile X syndrome, using the more accurate DNA-based testing procedures. 29 refs., 1 fig., 1 tab.« less
McGrath, Sara E.; Abbeduto, Leonard; Roberts, Jane E.
2016-01-01
Purpose Pragmatic language difficulties have been documented as part of the FMR1 premutation phenotype, yet the interplay between these features in mothers and the language outcomes of their children with fragile X syndrome is unknown. This study aimed to determine whether pragmatic language difficulties in mothers with the FMR1 premutation are related to the language development of their children. Method Twenty-seven mothers with the FMR1 premutation and their adolescent/young adult sons with fragile X syndrome participated. Maternal pragmatic language violations were rated from conversational samples using the Pragmatic Rating Scale (Landa et al., 1992). Children completed standardized assessments of vocabulary, syntax, and reading. Results Maternal pragmatic language difficulties were significantly associated with poorer child receptive vocabulary and expressive syntax skills, with medium effect sizes. Conclusions This work contributes to knowledge of the FMR1 premutation phenotype and its consequences at the family level, with the goal of identifying modifiable aspects of the child's language-learning environment that may promote the selection of treatments targeting the specific needs of families affected by fragile X. Findings contribute to our understanding of the multifaceted environment in which children with fragile X syndrome learn language and highlight the importance of family-centered intervention practices for this group. PMID:26895548
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lachiewicz, A.M.; Spiridigliozzi, G.A.; McConkie-Rosell, A.
1996-08-09
Fragile X DNA studies were carried out on all obligate carriers of a large fragile X family with 10 mentally retarded individuals. One 64-year-old carrier man with an altered FMR-1 allele was not described as being mentally retarded or as having any limitations in function. He was married, raised 8 children, and worked as an auto mechanic. On examination, he had macrocephaly and mild macroorchidism but few of the other typical physical findings of males with fragile X syndrome. His Full Scale IQ is 73, and his Vineland Adaptive Behavior Composite is 73. On the Woodcock-Johnson Psycho-Educational Battery-Revised, he achievedmore » standard scores of 64 in Reading, 55 in Math, and 83 in Knowledge. His DNA findings showed a broad smear on Southern blot analysis of 100-500 CGG repeats and no methylation at the EagI site upstream of the FMR-1 protein coding region. His FMR-1 protein production is 12% of normal. His daughters all have large premutations, with somatic instability in the size of the CGG repeat lengths. They all have evidence of academic underachievement and 2 have physical characteristics frequently described in individuals with fragile X. 21 refs., 3 figs.« less
Biochemical markers of bone turnover in children with clinical bone fragility.
Bowden, Sasigarn A; Akusoba, Chiazor I; Hayes, John R; Mahan, John D
2016-06-01
The role of biochemical bone turnover markers (BTMs) in assessing low bone mass and monitoring bisphosphonate treatment in pediatric patients with clinical bone fragility is not well established. The aim of the study was to examine the correlations of BTMs and the bone mineral density (BMD), and evaluate the effects of bisphosphonates therapy on BTMs in children with clinical bone fragility. Clinical data of 115 patients with clinical bone fragility (mean age 9.7±5.8 years), 102 of whom received bisphosphonates, were studied. Serum alkaline phosphatase (ALP), osteocalcin (OC), urine pyridinoline (PD) and deoxypyridinoline (DPD), BMD at baseline and subsequent years were analyzed. There was a significant negative correlation between urine PD and lumbar BMD (slope=-0.29, p<0.001). There were no correlations between BTMs and lumbar BMD Z-score. There was a significant positive correlation between serum OC and serum ALP, urine PD and DPD (p<0.001). Serum OC, urine PD and DPD index, as expressed as measured value/upper limit of normal value for age, decreased during the first 3 years of bisphosphonate therapy. In children with clinical bone fragility, BTMs correlated with each other, but not with lumbar BMD Z-score. While they were not reliable predictors of degree of low BMD, the bone markers showed suppression during bisphosphonate therapy and may be helpful in monitoring the response to therapy.
Wehbe, Ramsey M.; Spiridigliozzi, Gail A.; Melvin, Elizabeth; Dawson, Deborah V.; McConkie-Rosell, Allyn
2009-01-01
We report here our findings from adolescent and young adult females (ages 14–25) with a family history of fragile X syndrome regarding their perceptions of the optimal ages for 1) learning fragile X is inherited, 2) learning one could be a carrier for fragile X, and 3) offering carrier testing for fragile X. Three groups were enrolled: those who knew they were carriers or noncarriers and those who knew only they were at-risk to be a carrier. Only two of the 53 participants felt that offering carrier testing should be delayed until the age of 18 years. Participants who knew only that they were at-risk to be a carrier provided older optimal ages for offering carrier testing than those who knew their actual carrier status. Participants did not express regret or negative emotions about the timing of the disclosure of genetic risk information regarding their own experiences. Participants’ reasoning behind reported ages for informing about genetic risk and offering carrier testing varied depending on what type of information was being disclosed, which carrier status group the participant belonged to, and the preferred age for learning the information. Study findings suggest that decisions regarding the timing to inform about genetic risk and offer testing should be tailored to the individual needs of the child and his/her family. PMID:19449413
Monyak, R E; Emerson, D; Schoenfeld, B P; Zheng, X; Chambers, D B; Rosenfelt, C; Langer, S; Hinchey, P; Choi, C H; McDonald, T V; Bolduc, F V; Sehgal, A; McBride, S M J; Jongens, T A
2017-08-01
Fragile X syndrome (FXS) is an undertreated neurodevelopmental disorder characterized by low intelligence quotent and a wide range of other symptoms including disordered sleep and autism. Although FXS is the most prevalent inherited cause of intellectual disability, its mechanistic underpinnings are not well understood. Using Drosophila as a model of FXS, we showed that select expression of dfmr1 in the insulin-producing cells (IPCs) of the brain was sufficient to restore normal circadian behavior and to rescue the memory deficits in the fragile X mutant fly. Examination of the insulin signaling (IS) pathway revealed elevated levels of Drosophila insulin-like peptide 2 (Dilp2) in the IPCs and elevated IS in the dfmr1 mutant brain. Consistent with a causal role for elevated IS in dfmr1 mutant phenotypes, the expression of dfmr1 specifically in the IPCs reduced IS, and genetic reduction of the insulin pathway also led to amelioration of circadian and memory defects. Furthermore, we showed that treatment with the FDA-approved drug metformin also rescued memory. Finally, we showed that reduction of IS is required at different time points to rescue circadian behavior and memory. Our results indicate that insulin misregulation underlies the circadian and cognitive phenotypes displayed by the Drosophila fragile X model, and thus reveal a metabolic pathway that can be targeted by new and already approved drugs to treat fragile X patients.
Molecular medicine of fragile X syndrome: based on known molecular mechanisms.
Luo, Shi-Yu; Wu, Ling-Qian; Duan, Ran-Hui
2016-02-01
Extensive research on fragile X mental retardation gene knockout mice and mutant Drosophila models has largely expanded our knowledge on mechanism-based treatment of fragile X syndrome (FXS). In light of these findings, several clinical trials are now underway for therapeutic translation to humans. Electronic literature searches were conducted using the PubMed database and ClinicalTrials.gov. The search terms included "fragile X syndrome", "FXS and medication", "FXS and therapeutics" and "FXS and treatment". Based on the publications identified in this search, we reviewed the neuroanatomical abnormalities in FXS patients and the potential pathogenic mechanisms to monitor the progress of FXS research, from basic studies to clinical trials. The pathological mechanisms of FXS were categorized on the basis of neuroanatomy, synaptic structure, synaptic transmission and fragile X mental retardation protein (FMRP) loss of function. The neuroanatomical abnormalities in FXS were described to motivate extensive research into the region-specific pathologies in the brain responsible for FXS behavioural manifestations. Mechanism-directed molecular medicines were classified according to their target pathological mechanisms, and the most recent progress in clinical trials was discussed. Current mechanism-based studies and clinical trials have greatly contributed to the development of FXS pharmacological therapeutics. Research examining the extent to which these treatments provided a rescue effect or FMRP compensation for the developmental impairments in FXS patients may help to improve the efficacy of treatments.
Compaction of Ductile and Fragile Grains
NASA Astrophysics Data System (ADS)
Creissac, S.; Pouliquen, O.; Dalloz-Dubrujeaud, B.
2009-06-01
The compaction of powders into tablets is widely used in several industries (cosmetics, food, pharmaceutics…). In all these industries, the composition of the initial powder is complex, and the behaviour under compaction is not well known, also the mechanical behaviour of the tablets. The aim of this paper is to understand the behaviour (pressure vs density) of a simplified media made of fragile and ductile powders, varying the relative ratio of each powder. Some compaction experiments were carried out with glass beads (fragile) and Polyethylen Glycol powder (ductile). We observe two typical behaviours, depending on the relative volumic fraction of each component. A transition is pointed out, observing the evolution of the slope of the curve pressure/density. This transition is explained by geometrical considerations during compaction. A model is proposed, based on the assumption that the studied media can be compare to a diphasic material with a continuous phase (the ductile powder) and a discrete phase (the fragile powder). The result of this model is compare to the experimental results of compaction, and give a good prediction of the behaviour of the different mixing, knowing the behaviour of the ductile and the fragile phase separately. These results were also interpreted in terms of Heckel parameter which characterizes the ability of the powder to deform plastically under compaction. Some mechanical tests were also performed to compare the mechanical resitance of the obtained tablets.
Osteoporotic fragility fractures in African Americans: under-recognized and undertreated.
Alam, Neelofar M.; Archer, Juanita A.; Lee, Euni
2004-01-01
PURPOSE: To determine the frequency of diagnosing and treating osteoporosis in patients with fragility fractures. METHODOLOGY: Retrospective review of medical records from January 1992 to December 2002 at Howard University Hospital, an urban tertiary care teaching hospital with a predominantly African-American population. Men 50 years old and women 45 years old with fractures caused by low impact falls (fragility fractures) were included. The diagnosis of osteoporosis was based on history, x-rays and pathology reports as indicated by ICD-9 codes (733.00-733.09) and review of medical records. MAIN FINDINGS: Of 58,841 patients who were admitted during the study period, 1,248 patients (2.1%) had fractures. There were 323 patients (65%) who had fractures secondary to low-impact falls. However, only 29 (8.9%) of these had a diagnosis of osteoporosis. Of these, only five (19%) patients were discharged on antiosteoporotic medications, and only one patient was discharged with a bisphosphonate therapy. No patient had DXA scans. CONCLUSIONS: In the population studied, osteoporosis was missed in the majority of the patients as an underlying cause for fragility fractures in African Americans. These results strongly suggest that physicians should be more aware of osteoporosis as an essential cause of fragility fractures. Early recognition and treatment in African Americans and other ethnic groups can significantly decrease the morbidity, mortality and the healthcare costs. PMID:15624249
Jones, Peter J; Raeini-Sarjaz, Mahmoud; Jenkins, David J A; Kendall, Cyril W C; Vidgen, Edward; Trautwein, Elke A; Lapsley, Karen G; Marchie, Augustine; Cunnane, Stephen C; Connelly, Philip W
2005-02-01
Plant sterols, soy proteins, viscous fibers, and nuts are advised for cholesterol reduction, but their combined effect on plant sterol absorption has never been tested. We assessed their combined action on serum sterols in hyperlipidemic subjects who were following low-saturated fat diets before starting the study and who returned to these diets post-test. The 1-mon test (combination) diet was high in plant sterols (1 g/1,000 kcal), soy protein (23 g/1,000 kcal), viscous fiber (9 g/1,000 kcal), and almonds (14 g/1000 kcal). Fasting blood was obtained for serum lipids and sterols, and erythrocytes were obtained for fragility prior to and at 2-wk intervals during the study. The combination diet raised serum campesterol concentrations by 50% and beta-sitosterol by 27%, although these changes were not significant after Bonferroni correction; near-maximal rises were found by the end of the first week, but no change was found in red cell fragility despite a 29% reduction in the LDL cholesterol level. No significant associations were observed between changes in red cell fragility and blood lipids or sterols. We conclude that plant sterols had a minimal impact on serum sterol concentrations or red cell fragility in hyperlipidemic subjects on diets that greatly reduced their serum lipids.
Capillary Structures for Exploration Life Support (Capillary Structures)
2017-07-10
iss052e013081 (7/10/2017) --- The Capillary Structures for Exploration Life Support (Capillary Structures) investigation studies a new method using structures of specific shapes to manage fluid and gas mixtures. The investigation studies water recycling and carbon dioxide removal, benefiting future efforts to design lightweight, more reliable life support systems for future space missions.
Thermal modulation for gas chromatography
NASA Technical Reports Server (NTRS)
Waite, J. Hunter (Inventor); Libardoni, Mark (Inventor); Stewart, Kristine (Inventor); Block, Bruce P. (Inventor); Sacks, Richard D. (Inventor); Hasselbrink, Ernest F. (Inventor)
2007-01-01
A thermal modulator device for gas chromatography and associated methods. The thermal modulator device includes a recirculating fluid cooling member, an electrically conductive capillary in direct thermal contact with the cooling member, and a power supply electrically coupled to the capillary and operable for controlled resistive heating of the capillary. The capillary can include more than one separate thermally modulated sections.
Liu, Shaorong; Gao, Lin; Pu, Qiaosheng; Lu, Joann J; Wang, Xingjia
2006-02-01
We have recently developed a new process to create cross-linked polyacrylamide (CPA) coatings on capillary walls to suppress protein-wall interactions. Here, we demonstrate CPA-coated capillaries for high-efficiency (>2 x 10(6) plates per meter) protein separations by capillary zone electrophoresis (CZE). Because CPA virtually eliminates electroosmotic flow, positive and negative proteins cannot be analyzed in a single run. A "one-sample-two-separation" approach is developed to achieve a comprehensive protein analysis. High throughput is achieved through a multiplexed CZE system.
Construction of stable capillary networks using a microfluidic device.
Sudo, Ryo
2015-01-01
Construction of stable capillary networks is required to provide sufficient oxygen and nutrients to the deep region of thick tissues, which is important in the context of 3D tissue engineering. Although conventional in vitro culture models have been used to investigate the mechanism of capillary formation, recent advances in microfluidics technologies allowed us to control biophysical and biochemical culture environments more precisely, which led to the construction of functional and stable capillary networks. In this study, endothelial cells and mesenchymal stem cells were co-cultured in microfluidic devices to construct stable capillary networks, which resulted in the construction of luminal structures covered by pericytes. Interactions between endothelial cells and mesenchymal stem cells are also discussed in the context of capillary formation.
Extreme-UV electrical discharge source
Fornaciari, Neal R.; Nygren, Richard E.; Ulrickson, Michael A.
2002-01-01
An extreme ultraviolet and soft x-ray radiation electric capillary discharge source that includes a boron nitride housing defining a capillary bore that is positioned between two electrodes one of which is connected to a source of electric potential can generate a high EUV and soft x-ray radiation flux from the capillary bore outlet with minimal debris. The electrode that is positioned adjacent the capillary bore outlet is typically grounded. Pyrolytic boron nitride, highly oriented pyrolytic boron nitride, and cubic boron nitride are particularly suited. The boron nitride capillary bore can be configured as an insert that is encased in an exterior housing that is constructed of a thermally conductive material. Positioning the ground electrode sufficiently close to the capillary bore outlet also reduces bore erosion.
Weng, Kuo-Yao; Chou, Nien-Jen; Cheng, Jya-Wei
2008-07-01
An innovative vacuum capillary pneumatic actuation concept that can be used for point-of-care testing has been investigated. The vacuum glass capillaries are encapsulated within a laminated pouch and incorporated into the fluidic card. Vacuum glass capillaries broken by external force such as finger pressure, generate the pneumatic forces to induce liquid flow in the fluidic system. The sizes of vacuum capillary play a vital role in the pumping and metering functions of the system. The luteinizing hormone (LH) chromatographic immunoassay performances in the fluidic cards show consistency comparable to that obtained by manual micropipetting. The vacuum capillary pneumatic actuation will be applied in other complex handling step bioassays and lab-on-a-chip devices.
Phenotypic Variation and FMRP Levels in Fragile X
ERIC Educational Resources Information Center
Loesch, Danuta Z.; Huggins, Richard M.; Hagerman, Randi J.
2004-01-01
Data on the relationships between cognitive and physical phenotypes, and a deficit of fragile X mental retardation 1 (FMR1) gene-specific protein product, FMRP, are presented and discussed in context with earlier findings. The previously unpublished results obtained, using standard procedures of regression and correlations, showed highly…
Social Cognition in Adolescent Girls with Fragile X Syndrome
ERIC Educational Resources Information Center
Turkstra, Lyn S.; Abbeduto, Leonard; Meulenbroek, Peter
2014-01-01
This study aimed to characterize social cognition, executive functions (EFs), and everyday social functioning in adolescent girls with fragile X syndrome, and identify relationships among these variables. Participants were 20 girls with FXS and 20 age-matched typically developing peers. Results showed significant between-groups differences in…
Attention and Language in Fragile X
ERIC Educational Resources Information Center
Cornish, Kim; Sudhalter, Vicki; Turk, Jeremy
2004-01-01
Fragile X syndrome (FXS) is a well-recognized cause of mental retardation and developmental delay in males. Alongside the well-documented clinical characteristics of the condition, recent advances in technology and methodology have begun to define FXS at a number of different levels: genetic, brain structure and function, cognition, and behavior.…
Emotion Potentiated Startle in Fragile X Syndrome
ERIC Educational Resources Information Center
Ballinger, Elizabeth C.; Cordeiro, Lisa; Chavez, Alyssa D.; Hagerman, Randi J.; Hessl, David
2014-01-01
Social avoidance and anxiety are prevalent in fragile X syndrome (FXS) and are potentially mediated by the amygdala, a brain region critical for social behavior. Unfortunately, functional brain resonance imaging investigation of the amygdala in FXS is limited by the difficulties experienced by intellectually impaired and anxious participants. We…
Capacity Development for Education Systems in Fragile Contexts. Working Paper
ERIC Educational Resources Information Center
Davies, Lynn
2009-01-01
This paper examines fragility, capacity development and education and the links between these by analysing relevant research and policy literature. It proposes ways forward for action and reflection at national, regional and international levels. An important element of capacity development in education systems is the establishment of education…
Intergenerational Relationships and Union Stability in Fragile Families
ERIC Educational Resources Information Center
Hognas, Robin S.; Carlson, Marcia J.
2010-01-01
Using data from the Fragile Families and Child Wellbeing Study (N = 2,656), we examined the association between intergenerational relationships and parents' union stability 5 years after a baby's birth. Results showed that more amiable relationships between parents and each partner's parents, and children's spending more time with paternal…
Burgeson, Duane A.
1977-01-01
A package for fragile objects such as radioactive fusion pellets of micron size shipped in mounted condition or unmounted condition with a frangible inner container which is supported in a second inner container which in turn is supported in a final outer container, the second inner container having recesses for supporting alternate design inner containers.
Phonological Awareness and Reading in Boys with Fragile X Syndrome
ERIC Educational Resources Information Center
Adlof, Suzanne M.; Klusek, Jessica; Shinkareva, Svetlana V.; Robinson, Marissa L.; Roberts, Jane E.
2015-01-01
Background: Reading delays are well documented in children with fragile X syndrome (FXS), but few studies have examined linguistic precursors of reading in this population. This study examined the longitudinal development of phonological awareness and its relationship with basic reading in boys with FXS. Individual differences in genetic,…
The Neuroanatomy and Neuroendocrinology of Fragile X Syndrome
ERIC Educational Resources Information Center
Hessl, David; Rivera, Susan M.; Reiss, Allan L.
2004-01-01
Fragile X syndrome (FXS), caused by a single gene mutation on the X chromosome, offers a unique opportunity for investigation of gene-brain-behavior relationships. Recent advances in molecular genetics, human brain imaging, and behavioral studies have started to unravel the complex pathways leading to the cognitive, psychiatric, and physical…
On Using Vernier Acuity to Assess Magnocellular Sensitivity
ERIC Educational Resources Information Center
Skottun, Bernt C.; Skoyles, John R.
2010-01-01
A recent study [Keri, S., & Benedek, G. (2009). Visual pathway deficit in female fragile x premutation carriers: A potential endophenotype. "Brain and Cognition", 69, 291-295] has found Vernier acuity deficiencies together with contrast sensitivity defects consistent with a magnocellular deficit in female fragile x premutation carriers. This may…
ERIC Educational Resources Information Center
Frolli, A.; Piscopo, S.; Conson, M.
2015-01-01
Background: Individuals with fragile-X syndrome exhibit developmental delay, hyperexcitation and social anxiety; they also show lack of attention and hyperactivity. Few studies have investigated whether levels of functioning change with increasing age. Here, we explored developmental changes across adolescence in the cognitive and behavioural…
Multipartnered Fertility and Depression among Fragile Families
ERIC Educational Resources Information Center
Turney, Kristin; Carlson, Marcia J.
2011-01-01
We used data from the Fragile Families and Child Wellbeing Study to examine the association between multipartnered fertility (MPF)--when parents have children with more than one partner--and depression. Random-effects models suggested that MPF is associated with a greater likelihood of depression, net of family structure and other covariates.…
Inter-state Variation in the Burden of Fragility Fractures
USDA-ARS?s Scientific Manuscript database
Demographic differences may produce inter-state variation in the burden of osteoporosis. The objective of this study was to estimate the burden of fragility fractures by race/ethnicity, age, sex, and service site across 5 diverse and populous states. State inpatient databases for 2000 were used to ...
The Expressed Emotion of Mothers of Children with Fragile X Syndrome
ERIC Educational Resources Information Center
Coleman, Jeanine M.
2010-01-01
A review of the literature revealed that mothers with children with fragile X syndrome (FXS) face many challenges, including managing their child's behavior which is a defining characteristic of children with FXS (Epstein, Riley, & Sobesky, 2002). Parents and professionals have become increasingly aware through research and everyday experiences…
Medically Fragile Students and the Law: Supreme Court Rules.
ERIC Educational Resources Information Center
Brown, Frank
1999-01-01
In March 1999, the U.S. Supreme Court ruled that the Individuals with Disabilities Education Act regulations defining "related services" for disabled children meant paying nursing costs for Garret Frey, a medically fragile student enrolled in the Cedar Rapids (Idaho) Community School District. However, physicians' services are not…
2014-01-01
Fragile and Conflict Affected States present difficult contexts to achieve health system outcomes and are neglected in health systems research. This report presents key debates from the Consultation of the Collaboration for Applied Health Research and Delivery, Liverpool, June, 2014.
Fragile X Syndrome: An Aging Perspective
ERIC Educational Resources Information Center
Schneider, Andrea; Ligsay, Andrew; Hagerman, Randi J.
2013-01-01
Cognitive and behavioral correlates of molecular variations related to the FMR1 gene have been studied rather extensively, but research about the long-term outcome in individuals with fragile X spectrum disorders remains sparse. In this review, we present an overview of aging research and recent findings in regard to cellular and clinical…
Psychopharmacology in Fragile X Syndrome--Present and Future
ERIC Educational Resources Information Center
Berry-Kravis, Elizabeth; Potanos, Kristina
2004-01-01
In addition to cognitive disability, fragile X syndrome (FXS) is associated with behavioral problems that are often functionally limiting. There are few controlled trials to guide treatment; however, available information does suggest that medications can be quite helpful for a number of categories of behavioral disturbance in FXS. Specifically,…
Strengthening Fragile Families through Research and Practice
ERIC Educational Resources Information Center
Bembry, James X.
2011-01-01
Almost one third of all children in the United States are born to unmarried parents. This figure is even higher among poor and minority populations. Because of their heightened risk for economic and social problems and family dissolution, disadvantaged, unmarried parents have been called "fragile families." In 2002 the Bush administration…
Open-Label Memantine in Fragile X Syndrome
ERIC Educational Resources Information Center
Erickson, Craig A.; Mullett, Jennifer E.; McDougle, Christopher J.
2009-01-01
Glutamatergic dysfunction is implicated in the pathophysiology of fragile X syndrome (FXS). The purpose of this pilot study was to examine the effectiveness and tolerability of memantine for a number of target symptoms associated with FXS. Medical records describing open-label treatment with memantine in 6 patients with FXS and a comorbid…
Imitation in Fragile X Syndrome: Implications for Autism
ERIC Educational Resources Information Center
Macedoni-Luksic, Marta; Greiss-Hess, Laura; Rogers, Sally J.; Gosar, David; Lemons-Chitwood, Kerrie; Hagerman, Randi
2009-01-01
To address the specific impairment of imitation in autism, the imitation abilities of 22 children with fragile X syndrome (FXS) with and without autism were compared. Based on previous research, we predicted that children with FXS and autism would have significantly more difficulty with non-meaningful imitation tasks. After controlling for…
Hinderdael, Michaël; Strantza, Maria; De Baere, Dieter; Devesse, Wim; De Graeve, Iris; Terryn, Herman; Guillaume, Patrick
2017-01-01
Additive manufacturing (AM) of metals offers new possibilities for the production of complex structures. Up to now, investigations on the mechanical response of AM metallic parts show a significant spread and unexpected failures cannot be excluded. In this work, we focus on the detection of fatigue cracks through the integration of a Structural Health Monitoring (SHM) system in Ti-6Al-4V specimens. The working principle of the presented system is based on the integration of small capillaries that are capable of detecting fatigue cracks. Four-point bending fatigue tests have been performed on Ti-6Al-4V specimens with integrated capillaries and compared to the reference specimenswithout capillaries. Specimens were produced by conventional subtractive manufacturing of wrought material and AM, using the laser based Directed Energy Deposition (DED) process. In this study, we investigated the effect of the presence of the capillary on the fatigue strength and fatigue initiation location. Finite element (FEM) simulations were performed to validate the experimental test results. The presence of a drilled capillary in the specimens did not alter the fatigue initiation location. However, the laser based DED production process introduced roughness on the capillary surface that altered the fatigue initiation location to the capillary surface. The fatigue performance was greatly reduced when considering a printed capillary. It is concluded that the surface quality of the integrated capillary is of primary importance in order not to influence the structural integrity of the component to be monitored. PMID:28841186
Antonios, Tarek F T; Nama, Vivek; Wang, Duolao; Manyonda, Isaac T
2013-09-01
Preeclampsia is a major cause of maternal and neonatal mortality and morbidity. The incidence of preeclampsia seems to be rising because of increased prevalence of predisposing disorders, such as essential hypertension, diabetes, and obesity, and there is increasing evidence to suggest widespread microcirculatory abnormalities before the onset of preeclampsia. We hypothesized that quantifying capillary rarefaction could be helpful in the clinical prediction of preeclampsia. We measured skin capillary density according to a well-validated protocol at 5 consecutive predetermined visits in 322 consecutive white women, of whom 16 subjects developed preeclampsia. We found that structural capillary rarefaction at 20-24 weeks of gestation yielded a sensitivity of 0.87 with a specificity of 0.50 at the cutoff of 2 capillaries/field with the area under the curve of the receiver operating characteristic value of 0.70, whereas capillary rarefaction at 27-32 weeks of gestation yielded a sensitivity of 0.75 and a higher specificity of 0.77 at the cutoff of 8 capillaries/field with area under the curve of the receiver operating characteristic value of 0.82. Combining capillary rarefaction with uterine artery Doppler pulsatility index increased the sensitivity and specificity of the prediction. Multivariable analysis shows that the odds of preeclampsia are increased in women with previous history of preeclampsia or chronic hypertension and in those with increased uterine artery Doppler pulsatility index, but the most powerful and independent predictor of preeclampsia was capillary rarefaction at 27-32 weeks. Quantifying structural rarefaction of skin capillaries in pregnancy is a potentially useful clinical marker for the prediction of preeclampsia.
Nerve injury affects the capillary supply in rat slow and fast muscles differently.
Cebasek, Vita; Radochová, Barbora; Ribaric, Samo; Kubínová, Lucie; Erzen, Ida
2006-02-01
The goal of this study was to determine the acute effects of permanent denervation on the length density of the capillary network in rat slow soleus (SOL) and fast extensor digitorum longus (EDL) muscles and the effect of short-lasting reinnervation in slow muscle only. Denervation was performed by cutting the sciatic nerve. Both muscles were excised 2 weeks later. Reinnervation was studied 4 weeks after nerve crush in SOL muscle only. Capillaries and muscle fibres were visualised by triple immunofluorescent staining with antibodies against CD31 and laminin and with fluorescein-labelled Griffonia (Bandeira) simplicifolia lectin. A recently developed stereological approach allowing the estimation of the length of capillaries adjacent to each individual fibre (Lcap/Lfib) was employed. Three-dimensional virtual test grids were applied to stacks of optical images captured with a confocal microscope and their intersections with capillaries and muscle fibres were counted. Interrelationships among capillaries and muscle fibres were demonstrated with maximum intensity projection of the acquired stacks of optical images. The course of capillaries in EDL seemed to be parallel to the fibre axes, whereas in SOL, their preferential direction deviated from the fibre axes and formed more cross-connections among neighbouring capillaries. Lcap/Lfib was clearly reduced in denervated SOL but remained unchanged in EDL, although the muscle fibres significantly atrophied in both muscle types. When soleus muscle was reinnervated, capillary length per unit fibre length was completely restored. The physiological background for the different responses of the capillary network in slow and fast muscle is discussed.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hinderdael, Michaël; Strantza, Maria; De Baere, Dieter
Additive manufacturing (AM) of metals offers new possibilities for the production of complex structures. Up to now, investigations on the mechanical response of AM metallic parts show a significant spread and unexpected failures cannot be excluded. In this work, we focus on the detection of fatigue cracks through the integration of a Structural Health Monitoring (SHM) system in Ti-6Al-4V specimens. The working principle of the presented system is based on the integration of small capillaries that are capable of detecting fatigue cracks. Four-point bending fatigue tests have been performed on Ti-6Al-4V specimens with integrated capillaries and compared to the referencemore » specimenswithout capillaries. Specimens were produced by conventional subtractive manufacturing of wrought material and AM, using the laser based Directed Energy Deposition (DED) process. In this study, we investigated the effect of the presence of the capillary on the fatigue strength and fatigue initiation location. Finite element (FEM) simulations were performed to validate the experimental test results. The presence of a drilled capillary in the specimens did not alter the fatigue initiation location. However, the laser based DED production process introduced roughness on the capillary surface that altered the fatigue initiation location to the capillary surface. The fatigue performance was greatly reduced when considering a printed capillary. It is concluded that the surface quality of the integrated capillary is of primary importance in order not to influence the structural integrity of the component to be monitored.« less
Hinderdael, Michaël; Strantza, Maria; De Baere, Dieter; ...
2017-08-25
Additive manufacturing (AM) of metals offers new possibilities for the production of complex structures. Up to now, investigations on the mechanical response of AM metallic parts show a significant spread and unexpected failures cannot be excluded. In this work, we focus on the detection of fatigue cracks through the integration of a Structural Health Monitoring (SHM) system in Ti-6Al-4V specimens. The working principle of the presented system is based on the integration of small capillaries that are capable of detecting fatigue cracks. Four-point bending fatigue tests have been performed on Ti-6Al-4V specimens with integrated capillaries and compared to the referencemore » specimenswithout capillaries. Specimens were produced by conventional subtractive manufacturing of wrought material and AM, using the laser based Directed Energy Deposition (DED) process. In this study, we investigated the effect of the presence of the capillary on the fatigue strength and fatigue initiation location. Finite element (FEM) simulations were performed to validate the experimental test results. The presence of a drilled capillary in the specimens did not alter the fatigue initiation location. However, the laser based DED production process introduced roughness on the capillary surface that altered the fatigue initiation location to the capillary surface. The fatigue performance was greatly reduced when considering a printed capillary. It is concluded that the surface quality of the integrated capillary is of primary importance in order not to influence the structural integrity of the component to be monitored.« less
Noninvasive imaging of human foveal capillary network using dual-conjugate adaptive optics.
Popovic, Zoran; Knutsson, Per; Thaung, Jörgen; Owner-Petersen, Mette; Sjöstrand, Johan
2011-04-22
To demonstrate noninvasive imaging of human foveal capillary networks with a high-resolution, wide-field, dual-conjugate adaptive optics (DCAO) imaging instrument. The foveal capillary networks of five healthy subjects with no previous history of ocular or neurologic disease or surgery were imaged with a novel high-resolution, wide-field DCAO instrument. The foveal avascular zone (FAZ) in each image was defined using a manual procedure. An automated algorithm based on publicly available and custom-written software was used to identify vessels and extract morphologic FAZ and vessel parameters. Capillary densities were calculated in two annular regions of interest (ROIs) outside the FAZ (500 μm and 750 μm outer radius from the foveal center) and in the superior, inferior, temporal, and nasal quadrants within the two ROIs. Mean FAZ area was 0.302 ± 0.100 mm(2), and mean capillary density (length/area) in the inner ROI was 38.0 ± 4.0 mm(-1) and 36.4 ± 4.0 mm(-1) in the outer ROI. The difference in ROI capillary density was not significant. There was no significant difference in quadrant capillary density within the two ROIs or between quadrants irrespective of ROI. The authors have demonstrated a technique for noninvasive imaging and semiautomated detection and analysis of foveal capillaries. In comparison with other studies, their method yielded lower capillary densities than histology but similar results to the current clinical gold standard, fluorescein angiography. The increased field of view of the DCAO instrument opens up new possibilities for high-resolution noninvasive clinical imaging of foveal capillaries.
Lücker, Adrien; Secomb, Timothy W.; Weber, Bruno; Jenny, Patrick
2018-01-01
Capillary dysfunction impairs oxygen supply to parenchymal cells and often occurs in Alzheimer's disease, diabetes and aging. Disturbed capillary flow patterns have been shown to limit the efficacy of oxygen extraction and can be quantified using capillary transit time heterogeneity (CTH). However, the transit time of red blood cells (RBCs) through the microvasculature is not a direct measure of their capacity for oxygen delivery. Here we examine the relation between CTH and capillary outflow saturation heterogeneity (COSH), which is the heterogeneity of blood oxygen content at the venous end of capillaries. Models for the evolution of hemoglobin saturation heterogeneity (HSH) in capillary networks were developed and validated using a computational model with moving RBCs. Two representative situations were selected: a Krogh cylinder geometry with heterogeneous hemoglobin saturation (HS) at the inflow, and a parallel array of four capillaries. The heterogeneity of HS after converging capillary bifurcations was found to exponentially decrease with a time scale of 0.15–0.21 s due to diffusive interaction between RBCs. Similarly, the HS difference between parallel capillaries also drops exponentially with a time scale of 0.12–0.19 s. These decay times are substantially smaller than measured RBC transit times and only weakly depend on the distance between microvessels. This work shows that diffusive interaction strongly reduces COSH on a small spatial scale. Therefore, we conclude that CTH influences COSH yet does not determine it. The second part of this study will focus on simulations in microvascular networks from the rodent cerebral cortex. Actual estimates of COSH and CTH will then be given. PMID:29755365
Govoni, Virginia; Sanders, Thomas A B; Reidlinger, Dianne P; Darzi, Julia; Berry, Sarah E E; Goff, Louise M; Seed, Paul T; Chowienczyk, Philip J; Hall, Wendy L
2017-04-01
Healthy microcirculation is important to maintain the health of tissues and organs, most notably the heart, kidney and retina. Single components of the diet such as salt, lipids and polyphenols may influence microcirculation, but the effects of dietary patterns that are consistent with current dietary guidelines are uncertain. It was hypothesized that compliance to UK dietary guidelines would have a favourable effect on skin capillary density/recruitment compared with a traditional British diet (control diet). A 12-week randomized controlled trial in men and women aged 40-70 years was used to test whether skin microcirculation, measured by skin video-capillaroscopy on the dorsum of the finger, influenced functional capillary density (number of capillaries perfused under basal conditions), structural capillary density (number of anatomical capillaries perfused during finger cuff inflation) and capillary recruitment (percentage difference between structural and functional capillary density). Microvascular measures were available for 137 subjects out of the 165 participants randomized to treatment. There was evidence of compliance to the dietary intervention, and participants randomized to follow dietary guidelines showed significant falls in resting supine systolic, diastolic and mean arterial pressure of 3.5, 2.6 and 2.9 mmHg compared to the control diet. There was no evidence of differences in capillary density, but capillary recruitment was 3.5 % (95 % CI 0.2, 6.9) greater (P = 0.04) on dietary guidelines compared with control. Adherence to dietary guidelines may help maintain a healthy microcirculation in middle-aged men and women. This study is registered at www.isrctn.com as ISRCTN92382106.
Capillary Rise: Validity of the Dynamic Contact Angle Models.
Wu, Pingkeng; Nikolov, Alex D; Wasan, Darsh T
2017-08-15
The classical Lucas-Washburn-Rideal (LWR) equation, using the equilibrium contact angle, predicts a faster capillary rise process than experiments in many cases. The major contributor to the faster prediction is believed to be the velocity dependent dynamic contact angle. In this work, we investigated the dynamic contact angle models for their ability to correct the dynamic contact angle effect in the capillary rise process. We conducted capillary rise experiments of various wetting liquids in borosilicate glass capillaries and compared the model predictions with our experimental data. The results show that the LWR equations modified by the molecular kinetic theory and hydrodynamic model provide good predictions on the capillary rise of all the testing liquids with fitting parameters, while the one modified by Joos' empirical equation works for specific liquids, such as silicone oils. The LWR equation modified by molecular self-layering model predicts well the capillary rise of carbon tetrachloride, octamethylcyclotetrasiloxane, and n-alkanes with the molecular diameter or measured solvation force data. The molecular self-layering model modified LWR equation also has good predictions on the capillary rise of silicone oils covering a wide range of bulk viscosities with the same key parameter W(0), which results from the molecular self-layering. The advantage of the molecular self-layering model over the other models reveals the importance of the layered molecularly thin wetting film ahead of the main meniscus in the energy dissipation associated with dynamic contact angle. The analysis of the capillary rise of silicone oils with a wide range of bulk viscosities provides new insights into the capillary dynamics of polymer melts.
Hinderdael, Michaël; Strantza, Maria; De Baere, Dieter; Devesse, Wim; De Graeve, Iris; Terryn, Herman; Guillaume, Patrick
2017-08-25
Additive manufacturing (AM) of metals offers new possibilities for the production of complex structures. Up to now, investigations on the mechanical response of AM metallic parts show a significant spread and unexpected failures cannot be excluded. In this work, we focus on the detection of fatigue cracks through the integration of a Structural Health Monitoring (SHM) system in Ti-6Al-4V specimens. The working principle of the presented system is based on the integration of small capillaries that are capable of detecting fatigue cracks. Four-point bending fatigue tests have been performed on Ti-6Al-4V specimens with integrated capillaries and compared to the reference specimenswithout capillaries. Specimens were produced by conventional subtractive manufacturing of wrought material and AM, using the laser based Directed Energy Deposition (DED) process. In this study, we investigated the effect of the presence of the capillary on the fatigue strength and fatigue initiation location. Finite element (FEM) simulations were performed to validate the experimental test results. The presence of a drilled capillary in the specimens did not alter the fatigue initiation location. However, the laser based DED production process introduced roughness on the capillary surface that altered the fatigue initiation location to the capillary surface. The fatigue performance was greatly reduced when considering a printed capillary. It is concluded that the surface quality of the integrated capillary is of primary importance in order not to influence the structural integrity of the component to be monitored.
Lücker, Adrien; Secomb, Timothy W; Weber, Bruno; Jenny, Patrick
2018-01-01
Capillary dysfunction impairs oxygen supply to parenchymal cells and often occurs in Alzheimer's disease, diabetes and aging. Disturbed capillary flow patterns have been shown to limit the efficacy of oxygen extraction and can be quantified using capillary transit time heterogeneity (CTH). However, the transit time of red blood cells (RBCs) through the microvasculature is not a direct measure of their capacity for oxygen delivery. Here we examine the relation between CTH and capillary outflow saturation heterogeneity (COSH), which is the heterogeneity of blood oxygen content at the venous end of capillaries. Models for the evolution of hemoglobin saturation heterogeneity (HSH) in capillary networks were developed and validated using a computational model with moving RBCs. Two representative situations were selected: a Krogh cylinder geometry with heterogeneous hemoglobin saturation (HS) at the inflow, and a parallel array of four capillaries. The heterogeneity of HS after converging capillary bifurcations was found to exponentially decrease with a time scale of 0.15-0.21 s due to diffusive interaction between RBCs. Similarly, the HS difference between parallel capillaries also drops exponentially with a time scale of 0.12-0.19 s. These decay times are substantially smaller than measured RBC transit times and only weakly depend on the distance between microvessels. This work shows that diffusive interaction strongly reduces COSH on a small spatial scale. Therefore, we conclude that CTH influences COSH yet does not determine it. The second part of this study will focus on simulations in microvascular networks from the rodent cerebral cortex. Actual estimates of COSH and CTH will then be given.
A many-body dissipative particle dynamics study of forced water-oil displacement in capillary.
Chen, Chen; Zhuang, Lin; Li, Xuefeng; Dong, Jinfeng; Lu, Juntao
2012-01-17
The forced water-oil displacement in capillary is a model that has important applications such as the groundwater remediation and the oil recovery. Whereas it is difficult for experimental studies to observe the displacement process in a capillary at nanoscale, the computational simulation is a unique approach in this regard. In the present work, the many-body dissipative particle dynamics (MDPD) method is employed to simulate the process of water-oil displacement in capillary with external force applied by a piston. As the property of all interfaces involved in this system can be manipulated independently, the dynamic displacement process is studied systematically under various conditions of distinct wettability of water in capillary and miscibility between water and oil as well as of different external forces. By analyzing the dependence of the starting force on the properties of water/capillary and water/oil interfaces, we find that there exist two different modes of the water-oil displacement. In the case of stronger water-oil interaction, the water particles cannot displace those oil particles sticking to the capillary wall, leaving a low oil recovery efficiency. To minimize the residual oil content in capillary, enhancing the wettability of water and reducing the external force will be beneficial. This simulation study provides microscopic insights into the water-oil displacement process in capillary and guiding information for relevant applications. © 2011 American Chemical Society
Capillary flow enhancement in rectangular polymer microchannels with a deformable wall.
Anoop, R; Sen, A K
2015-07-01
We report the capillary flow enhancement in rectangular polymer microchannels, when one of the channel walls is a deformable polymer membrane. We provide detailed insight into the physics of elastocapillary interaction between the capillary flow and elastic membrane, which leads to significant improvements in capillary flow performance. As liquid flows by capillary action in such channels, the deformable wall deflects inwards due to the Young-Laplace pressure drop across the liquid meniscus. This, in turn, decreases the radius of curvature of the meniscus and increases the driving capillary pressure. A theoretical model is proposed to predict the resultant increase in filling speed and rise height, respectively, in deformable horizontal and vertical microchannels having large aspect ratios. A non-dimensional parameter J, which represents the ratio of the capillary force to the mechanical restoring force, is identified to quantify the elastocapillary effects in terms of the improvement in filling speed (for J>0.238) and the condition for channel collapse (J>1). The theoretical predictions show good agreement with experimental data obtained using deformable rectangular poly(dimethylsiloxane) microchannels. Both model predictions and experimental data show that over 15% improvement in the Washburn coefficient in horizontal channels, and over 30% improvement in capillary rise height in vertical channels, are possible prior to channel collapse. The proposed technique of using deformable membranes as channel walls is a viable method for capillary flow enhancement in microfluidic devices.
Stress failure of pulmonary capillaries: role in lung and heart disease
NASA Technical Reports Server (NTRS)
West, J. B.; Mathieu-Costello, O.
1992-01-01
Pulmonary capillaries have extremely thin walls to allow rapid exchange of respiratory gases across them. Recently it has been shown that the wall stresses become very large when the capillary pressure is raised, and in anaesthetised rabbits, ultrastructural damage to the walls is seen at pressures of 40 mm Hg and above. The changes include breaks in the capillary endothelial layer, alveolar epithelial layer, and sometimes all layers of the wall. The strength of the thin part of the capillary wall can be attributed to the type IV collagen in the extracellular matrix. Stress failure of pulmonary capillaries results in a high-permeability form of oedema, or even frank haemorrhage, and is apparently the mechanism of neurogenic pulmonary oedema and high-altitude pulmonary oedema. It also explains the exercise-induced pulmonary haemorrhage that occurs in all racehorses. Several features of mitral stenosis are consistent with stress failure. Overinflation of the lung also leads to stress failure, a common cause of increased capillary permeability in the intensive care environment. Stress failure also occurs if the type IV collagen of the capillary wall is weakened by autoantibodies as in Goodpasture's syndrome. Neutrophil elastase degrades type IV collagen and this may be the starting point of the breakdown of alveolar walls that is characteristic of emphysema. Stress failure of pulmonary capillaries is a hitherto overlooked and potentially important factor in lung and heart disease.
Guo, Heying; Niu, Xiaoying; Pan, Congjie; Yi, Tao; Chen, Hongli; Chen, Xingguo
2017-06-01
Inspired by the chiral recognition ability of β-cyclodextrin and the natural adhesive properties of polydopamine under alkaline conditions, in this study, a rapid and in situ modification strategy was developed to fabricate β-cyclodextrin/polydopamine composite material coated-capillary columns for open tubular capillary electrochromatography. The results of scanning electron microscopy, FTIR spectroscopy, streaming potential, and electro-osmotic flow studies indicated that β-cyclodextrin/polydopamine was successfully fixed on the inner wall of the capillary column. This coating can be achieved within 1 h affording a greatly reduced capillary preparation time. The performance of the β-cyclodextrin/polydopamine-coated capillary was validated by the analysis of seven pairs of chiral analytes, namely epinephrine, norepinephrine, isoprenaline, terbutaline, verapamil, tryptophane, carvedilol. Good enantioseparation efficiencies were achieved for all. For three consecutive runs, the relative standard deviations for the migration times of the analytes for intraday, interday, and column-to-column repeatability were in the range of 0.41-1.74, 1.03-4.18, and 1.66-8.24%, respectively. Moreover, the separation efficiency of the β-cyclodextrin/polydopamine-coated capillary column did not decrease obviously over 90 runs. The strategy should also be feasible to introduce and immobilize other chiral selectors on the inner walls surface of capillary columns. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Bao, Tao; Zhang, Juan; Zhang, Wenpeng; Chen, Zilin
2015-02-13
Much attention is being paid to applying metal-organic frameworks (MOFs) as stationary phases in chromatography because of their fascinating properties, such as large surface-to-volume ratios, high levels of porosity, and selective adsorption. HKUST-1 is one of the best-studied face-centered-cubic MOF containing nano-sized channels and side pockets for film growth. However, growth of HKUST-1 framework inside capillary column as stationary phase for capillary electrochromatography is a challenge work. In this work, we carry out the growth of HKUST-1 on the inner wall of capillary by using liquid-phase epitaxy process at room temperature. The fabricated HKUST-1@capillary can be successfully used for the separation of substituted benzene including methylbenzene, ethylbenzene, styrene, chlorobenzene, bromobenzene, o-dichlorobenzene, benzene series, phenolic acids, and benzoic acids derivates. High column efficiency of 1.5×10(5) N/m for methylbenzene was achieved. The formation of HKUST-1 grown in the capillary was confirmed and characterized by scanning electron microscopy images, Fourier transform infrared spectra and X-ray diffraction. The column showed long lifetime and excellent stability. The relative standard deviations for intra-day and inter-day repeatability of the HKUST-1@capillary were lower than 7%. Copyright © 2015 Elsevier B.V. All rights reserved.
Application of CHESS single-bounce capillaries at synchrotron beamlines
NASA Astrophysics Data System (ADS)
Huang, R.; Szebenyi, T.; Pfeifer, M.; Woll, A.; Smilgies, D.-M.; Finkelstein, K.; Dale, D.; Wang, Y.; Vila-Comamala, J.; Gillilan, R.; Cook, M.; Bilderback, D. H.
2014-03-01
Single-bounce capillaries are achromatic X-ray focusing optics that can provide efficient and high demagnification focusing with large numerical apertures. Capillary fabrication at CHESS can be customized according to specific application requirements. Exemplary applications are reviewed in this paper, as well as recent progress on condensers for high-resolution transmission X-ray microscopy and small focal size capillaries.
A simulation model of the oxygen alveolo-capillary exchange in normal and pathological conditions.
Brighenti, Chiara; Gnudi, Gianni; Avanzolini, Guido
2003-05-01
This paper presents a mathematical model of the oxygen alveolo-capillary exchange to provide the capillary oxygen partial pressure profile in normal and pathological conditions. In fact, a thickening of the blood-gas barrier, heavy exercise or a low oxygen partial pressure (PO2) in the alveolar space can reduce the O2 alveolo-capillary exchange. Since the reversible binding between haemoglobin and oxygen makes it impossible to determine the closed form for the mathematical description of the PO2 profile along the pulmonary capillaries, an approximate analytical solution of the capillary PO2 profile is proposed. Simulation results are compared with the capillary PO2 profile obtained by numerical integration and by a piecewise linear interpolation of the oxyhaemoglobin dissociation curve. Finally, the proposed model is evaluated in a large range of physiopathological diffusive conditions. The good fit to numerical solutions in all experimental conditions seems to represent a substantial improvement with respect to the approach based on a linear approximation of the oxyhaemoglobin dissociation curve, and makes this model a candidate to be incorporated into the integrated descriptions of the entire respiratory system, where the datum of primary interest is the value of end capillary PO2.
Cerebral capillary velocimetry based on temporal OCT speckle contrast.
Choi, Woo June; Li, Yuandong; Qin, Wan; Wang, Ruikang K
2016-12-01
We propose a new optical coherence tomography (OCT) based method to measure red blood cell (RBC) velocities of single capillaries in the cortex of rodent brain. This OCT capillary velocimetry exploits quantitative laser speckle contrast analysis to estimate speckle decorrelation rate from the measured temporal OCT speckle signals, which is related to microcirculatory flow velocity. We hypothesize that OCT signal due to sub-surface capillary flow can be treated as the speckle signal in the single scattering regime and thus its time scale of speckle fluctuations can be subjected to single scattering laser speckle contrast analysis to derive characteristic decorrelation time. To validate this hypothesis, OCT measurements are conducted on a single capillary flow phantom operating at preset velocities, in which M-mode B-frames are acquired using a high-speed OCT system. Analysis is then performed on the time-varying OCT signals extracted at the capillary flow, exhibiting a typical inverse relationship between the estimated decorrelation time and absolute RBC velocity, which is then used to deduce the capillary velocities. We apply the method to in vivo measurements of mouse brain, demonstrating that the proposed approach provides additional useful information in the quantitative assessment of capillary hemodynamics, complementary to that of OCT angiography.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hopper, Kenneth D.; Grenko, Ronald T.; Fisher, Alicia I.
1996-09-15
Purpose: To test the value of the nonaspiration, or capillary, biopsy technique by experimental comparison with the conventional fine-needle aspiration technique using various needle gauges and lengths. Methods: On fresh hepatic and renal tissue from five autopsies, multiple biopsy specimens were taken with 20, 22, and 23-gauge Chiba needles of 5, 10, 15, and 20-cm length, using the aspiration technique and the capillary technique. The resultant specimens were graded on the basis of a grading scheme by a cytopathologist who was blinded to the biopsy technique. Results: The capillary technique obtained less background blood or clot which could obscure diagnosticmore » tissue, although not significantly different from the aspiration technique (p= 0.2). However, for the amount of cellular material obtained, retention of appropriate architecture, and mean score, the capillary technique performed statistically worse than aspiration biopsy (p < 0.01). In addition, with decreasing needle caliber (increasing needle gauge) and increasing length, the capillary biopsy was inferior to the aspiration biopsy. Conclusion: The capillary biopsy technique is inferior to the aspiration technique according to our study. When the capillary technique is to be applied, preference should be given to larger caliber, shorter needles.« less
Capillary electrophoresis: principles and applications in illicit drug analysis.
Tagliaro, F; Turrina, S; Smith, F P
1996-02-09
Capillary electrophoresis, which appeared in the early 1980s, is now rapidly expanding into many scientific disciplines, including analytical chemistry, biotechnology and biomedical and pharmaceutical sciences. In capillary electrophoresis,electrokinetic separations are carried out in tiny capillaries at high voltages (10-30 kV), thus obtaining high efficiencies (N > 10(5)) and excellent mass sensitivities (down to 10(-18)-10(-20) moles). The main features of capillary electrophoresis are: versatility of application (from inorganic ions to large DNA fragments), use of different separation modes with different selectivity, extremely low demands on sample volume, negligible running costs, possibility of interfacing with different detection systems, ruggedness and simplicity of instrumentation. Capillary electrophoresis applications in forensic sciences have appeared only recently, but are now rapidly growing, particularly in forensic toxicology. The present paper briefly describes the basic principles of capillary electrophoresis, from both the instrumental and analytical points of view. Furthermore, the main applications in the analysis of illicit/controlled drugs in both illicit preparations and biological samples are presented and discussed (43 references). It is concluded that the particular separation mechanism and the high complementarity of this technique to chromatography makes capillary electrophoresis a new powerful tool of investigation in the hands of forensic toxicologists.
[Structure of newly formed capillaries of the rabbit cornea (electron microscopic study)].
Gurina, O Iu; Karaganov, Ia L
1984-08-01
Owing to a complex application of topical analysis and tracer technique, it is possible to carry out a light optic and electron microscopic investigation of newly formed capillaries growing in the rabbit cornea after its chemical burn. The ultrastructural analysis demonstrates certain polymorphism of morphological organization of endotheliocyte in the newly formed capillaries. There is a rather elevated amount of free ribosomes, mitochondria, microtubules and microfilaments in cytoplasm. The granular endoplasmic reticulum and Golgi complex are hypertrophied. Weibel--Palade bodies appear. Taking into account certain morpho-functional peculiarities of endothelial cells along the course of the growing capillaries, on the 8th day of growth three zone are distinguished: 1--area of nondifferentiated endothelium (apex of the capillary), 2--transitional zone, 3--zone of relatively differentiated endothelium situating in the place where the capillary gets off the parental vessel. According to the zones distinguished, the ways of trans-endothelial transport of molecules are investigated. In formation of the capillary barrier-transport function an important role belongs to polymorphism of the endothelial cells along the course of the growing capillary which is determined by differentiation degree of these cells depending on their participation in permeability.
Instability of the capillary bridge
NASA Astrophysics Data System (ADS)
Pare, Gounseti; Hoepffner, Jerome
2014-11-01
Capillary adhesion is a physical mechanism that maintains two bodies in contact by capillarity through a liquid ligament. The capillary bridge is an idealization of this capillary adhesion. In this study we first focus on the classical case of the stability of the capillary bridge. Secondly we study a slightly more complex configuration, imagining a flow in the capillary bridge as in the case of the dynamics of the neck of a liquid ligament, in its withdrawal under the effect of capillarity. Inspired by the experiments on soap films of Plateau, the configuration analyzed consists of an initially axisymmetric, mass of fluid held by surface tension forces between two parallel, coaxial, solid pipes of the same diameter. The results presented are obtained by numerical simulations using the free software, Gerris Flow Solver. We first focus on the capillary Venturi. In the static configuration the stability diagram of the capillary bridge obtained is in perfect agreement with the results of Lev A. Slobozhanin. In the dynamic case we develop a matlab code based on the one dimensional equations of Eggers and Dupont. The comparison of the bifurcation diagram obtained and the numerical simulations shows a good agreement.
Influence of the capillary on the ignition of the transient spark discharge
NASA Astrophysics Data System (ADS)
Gerling, T.; Hoder, T.; Brandenburg, R.; Bussiahn, R.; Weltmann, K.-D.
2013-04-01
A self-pulsing negative dc discharge in argon generated in a needle-to-plane geometry at open atmosphere is investigated. Additionally, the needle electrode can be surrounded by a quartz capillary. It is shown that the relative position of the capillary end to the needle tip strongly influences the discharge inception and its spatio-temporal dynamics. Without the capillary for the selected working parameters a streamer corona is ignited, but when the capillary surrounds the needle, the transient spark (TS) discharge is ignited after a pre-streamer (PS) occurs. The time between PS and TS discharge depends on the relative capillary end position. The existence of the PS is confirmed by electro-optical characterization. Furthermore, spectrally and spatio-temporally resolved cross-correlation spectroscopy is applied to show the most active region of pre-phase emission activity as indicators for high local electric field strength. The results indicate that with a capillary in place, the necessary energy input of the pre-phase into the system is mainly reduced by additional electrical fields at the capillary edge. Even such a small change as a shift of dielectric surface close to the plasma largely changes the energy balance in the system.
Capillary Contact Angle in a Completely Wet Groove
NASA Astrophysics Data System (ADS)
Parry, A. O.; Malijevský, A.; Rascón, C.
2014-10-01
We consider the phase equilibria of a fluid confined in a deep capillary groove of width L with identical side walls and a bottom made of a different material. All walls are completely wet by the liquid. Using density functional theory and interfacial models, we show that the meniscus separating liquid and gas phases at two phase capillary coexistence meets the bottom capped end of the groove at a capillary contact angle θcap(L) which depends on the difference between the Hamaker constants. If the bottom wall has a weaker wall-fluid attraction than the side walls, then θcap>0 even though all the isolated walls are themselves completely wet. This alters the capillary condensation transition which is now first order; this would be continuous in a capped capillary made wholly of either type of material. We show that the capillary contact angle θcap(L) vanishes in two limits, corresponding to different capillary wetting transitions. These occur as the width (i) becomes macroscopically large, and (ii) is reduced to a microscopic value determined by the difference in Hamaker constants. This second wetting transition is characterized by large scale fluctuations and essential critical singularities arising from marginal interfacial interactions.
A model for capillary rise in micro-tube restrained by a sticky layer
NASA Astrophysics Data System (ADS)
Shen, Anqi; Xu, Yun; Liu, Yikun; Cai, Bo; Liang, Shuang; Wang, Fengjiao
2018-06-01
Fluid transport in a microscopic capillary under the effects of a sticky layer was theoretically investigated. A model based on the classical Lucas-Washburn (LW) model is proposed for the meniscus rise with the sticky layer present. The sticky layer consists of two parts: a fixed (located at the wall) and a movable part (located on the inside of the capillary), affecting the micro-capillary flow in different ways. Within our model, the movable layer is defined by the capillary radius and pressure gradient. From the model it follows that the fixed sticky layer leads to a decrease of capillary radius, while the movable sticky layer increases flow resistance. The movable layer thickness varies with the pressure gradient, which in turn varies with the rising of the meniscus. The results of our theoretical calculation also prove that the capillary radius has a greater effect on the meniscus height, rather than the additional resistance caused by the movable layer. Moreover, the fixed sticky layer, which affects the capillary radius, has a greater influence than the movable sticky layer. We conclude that the sticky layer causes a lower imbibition height than the LW model predicts.
Hall, Aaron C.; Hosking, F. Michael ,; Reece, Mark
2003-06-24
A capillary test specimen, method, and system for visualizing and quantifying capillary flow of liquids under realistic conditions, including polymer underfilling, injection molding, soldering, brazing, and casting. The capillary test specimen simulates complex joint geometries and has an open cross-section to permit easy visual access from the side. A high-speed, high-magnification camera system records the location and shape of the moving liquid front in real-time, in-situ as it flows out of a source cavity, through an open capillary channel between two surfaces having a controlled capillary gap, and into an open fillet cavity, where it subsequently forms a fillet on free surfaces that have been configured to simulate realistic joint geometries. Electric resistance heating rapidly heats the test specimen, without using a furnace. Image-processing software analyzes the recorded images and calculates the velocity of the moving liquid front, fillet contact angles, and shape of the fillet's meniscus, among other parameters.
Determining bruise etiology in muscle tissue using finite element analysis.
Tang, Kevin; Sharpe, Wyatt; Schulz, Alexandra; Tam, Edric; Grosse, Ian; Tis, John; Cullinane, Dennis
2014-03-01
Bruising, the result of capillary failure, is a common physical exam finding due to blunt trauma and, depending on location and severity, a potential indicator of abuse. Despite its clinical relevance, few studies have investigated the etiology of capillary failure. The goal of this study was to determine whether capillaries primarily fail under shear stress or hydraulic-induced tensile stress. An arteriole bifurcating into four capillaries was modeled using ANSYS 14.0 (®) . The capillaries were embedded in muscle tissue and a pressure of 20.4 kPa was applied. Any tensile stress exceeding 8.4 × 10(4) Pa was considered failure. Results showed that failure occurred directly under the impact zone and where capillaries bifurcated, rather than along the line of greatest shear stress, indicating that internal tensile stress is likely the primary mode of capillary failure in bruising. These results are supported by the concept that bruising can occur via blunt trauma in which no shearing lacerations occur. © 2013 American Academy of Forensic Sciences.
Desiderio, C; Fanali, S
2000-10-20
In this study capillary electrochromatography (CEC) was utilized for the separation of ten non-steroidal anti-inflammatory drugs (NSAIDs). Experiments were carried out in a commercially available CE instrument using a packed capillary with RP-18 silica particles where the stationary phase completely filled the capillary. The mobile phase consisted of a mixture of ammonium formate buffer pH 2.5 and acetonitrile. Selectivity and resolution were studied changing the pH and the concentration of the buffer, the acetonitrile content mobile phase and the capillary temperature. The optimum experimental conditions for CEC separation of the studied drug mixture were found using 50 mM ammonium formate pH 2.5-acetonitrile (40:60) at 25 degrees C. The CEC capillary was coupled to an electrospray mass spectrometer for the characterization of the NSAIDs. A mobile phase composed by the same buffer but with a higher concentration of acetonitrile (90%) was used in order to speed up the separation of analytes.
Laser beam coupling with capillary discharge plasma for laser wakefield acceleration applications
NASA Astrophysics Data System (ADS)
Bagdasarov, G. A.; Sasorov, P. V.; Gasilov, V. A.; Boldarev, A. S.; Olkhovskaya, O. G.; Benedetti, C.; Bulanov, S. S.; Gonsalves, A.; Mao, H.-S.; Schroeder, C. B.; van Tilborg, J.; Esarey, E.; Leemans, W. P.; Levato, T.; Margarone, D.; Korn, G.
2017-08-01
One of the most robust methods, demonstrated to date, of accelerating electron beams by laser-plasma sources is the utilization of plasma channels generated by the capillary discharges. Although the spatial structure of the installation is simple in principle, there may be some important effects caused by the open ends of the capillary, by the supplying channels etc., which require a detailed 3D modeling of the processes. In the present work, such simulations are performed using the code MARPLE. First, the process of capillary filling with cold hydrogen before the discharge is fired, through the side supply channels is simulated. Second, the simulation of the capillary discharge is performed with the goal to obtain a time-dependent spatial distribution of the electron density near the open ends of the capillary as well as inside the capillary. Finally, to evaluate the effectiveness of the beam coupling with the channeling plasma wave guide and of the electron acceleration, modeling of the laser-plasma interaction was performed with the code INF&RNO.
Kuchin, Igor V; Starov, Victor M
2016-05-31
A theory of contact angle hysteresis of a meniscus inside thin capillaries with smooth, homogeneous solid walls is developed in terms of surface forces (disjoining/conjoining pressure isotherm) using a quasi-equilibrium approach. The disjoining/conjoining pressure isotherm includes electrostatic, intermolecular, and structural components. The values of the static receding θr, advancing θa, and equilibrium θe contact angles in thin capillaries were calculated on the basis of the shape of the disjoining/conjoining pressure isotherm. It was shown that both advancing and receding contact angles depend on the capillary radius. The suggested mechanism of the contact angle hysteresis has a direct experimental confirmation: the process of receding is accompanied by the formation of thick β-films on the capillary walls. The effect of the transition from partial to complete wetting in thin capillaries is predicted and analyzed. This effect takes place in very thin capillaries, when the receding contact angle decreases to zero.
Effects of anesthesia on the cerebral capillary blood flow in young and old mice
NASA Astrophysics Data System (ADS)
Moeini, Mohammad; Tabatabaei, Maryam S.; Bélanger, Samuel; Avti, Pramod; Castonguay, Alexandre; Pouliot, Philippe; Lesage, Frédéric
2015-03-01
Despite recent findings on the possible role of age-related cerebral microvasculature changes in cognition decline, previous studies of capillary blood flow in aging (using animal models) are scarce and limited to anesthetized conditions. Since anesthesia can have different effects in young and old animals, it may introduce a confounding effect in aging studies. The present study aimed to eliminate the potential confound introduced by anesthesia by measuring capillary blood flow parameters in both awake conditions and under isoflurane anesthesia. We used 2-photon laser scanning fluorescence microscopy to measure capillary diameter, red blood cell velocity and flux, hematocrit and capillary volumetric flow in individual capillaries in the barrel cortex of 6- and 24-month old C57Bl/6 mice. It was observed that microvascular properties are significantly affected by anesthesia leading to different trends in capillary blood flow parameters with aging when measured under awake or anesthetized conditions. The findings in this study suggest taking extra care in interpreting aging studies from anesthetized animals.
Kubán, Pavel; Kubán, Petr; Kubán, Vlastimil; Hauser, Peter C; Bocek, Petr
2008-05-09
In this paper capillary electrochromatography of alkali and alkaline-earth metal cations in open tubular capillary columns is described. Capillary columns are prepared by coating fused silica capillaries of 75 microm I.D. with poly(butadiene-maleic acid) copolymer (PBMA) in multiple layers. Thermally initiated radical polymerization is used to crosslink the stationary phase. Capillary columns with different number of stationary phase layers can be prepared and allow for the adjustment of separation selectivity in the electrochromatographic mode. Fast and sensitive separations of common inorganic cations are achieved in less than 6 min in a 60 cm capillary column with on-column capacitively coupled contactless conductivity detector. Limits of detection (S/N=3) for the determination of alkali and alkaline-earth metal cations range from 0.3 to 2.5 microM and repeatability is better than 0.5, 4.5 and 6.1% for migration times, peak heights and peak areas, respectively.
Fatal Primary Capillary Leak Syndrome in a Late Preterm Newborn.
Kulihova, Katarina; Prochazkova, Martina; Semberova, Jana; Janota, Jan
2016-10-01
Primary capillary leak syndrome is a rare disease of unknown etiology, characterized by episodes of vascular collapse and plasma extravasation, which may lead to multiple organ failure. Primary capillary leak is extremely rare in children. The authors report a case of a late preterm newborn with fatal capillary leak syndrome of unknown etiology, manifesting as hypotension unresponsive to treatment, extravasation leading to generalised edema, disseminated intravascular coagulation and finally, multiple organ dysfunction syndrome. Aggressive volumotherapy and a combination of inotropes and high doses of terlipressin did not influence systemic vascular collapse and plasma extravasation. The newborn developed multiple organ failure and died on day 27 of life. Investigations performed failed to reveal any specific cause of capillary leak. This is the first report of a fatal primary capillary leak syndrome in a newborn.
Intradural Extramedullary Capillary Hemangioma in the Upper Cervical Spine: First Report.
Bouali, Sofiene; Maatar, Nidhal; Bouhoula, Asma; Abderrahmen, Khansa; Kallel, Jalel; Jemel, Hafedh
2016-08-01
The occurrence of intradural extramedullary capillary hemangiomas is exceedingly rare. To date, only 39 cases of intradural extramedullary capillary hemangiomas have been reported in the English literature, and all of these cases have been described at the lumbar and thoracic spinal levels. To our knowledge, this report is the first case of capillary hemangiomas of the cervical spine in the literature. In general, this entity is misdiagnosed preoperatively as a neoplasm. A 29-year-old man presented with neck pain and progressive gait disturbance, and was diagnosed with an intradural extramedullary capillary hemangioma in the cervical region. Although rare, our case demonstrates that capillary hemangioma should be considered in the differential diagnosis of intradural extramedullary tumor of the cervical spine. Copyright © 2016 Elsevier Inc. All rights reserved.
Managment of superficial infantile capillary hemangiomas with topical timolol maleate solution.
Rizvi, Syed Ali Raza; Yusuf, Faraz; Sharma, Rajeev; Rizvi, Syed Wajahat Ali
2015-01-01
Capillary hemangioma is the most common benign tumor of eyelids and orbit in children. Recently, a topical beta blocker has been reported as an effective treatment for superficial capillary hemangiomas. We present a case report of two children having large capillary hemangiomas who responded well to topical treatment by 0.5% timolol maleate solution. After 12 months of treatment, the lesion has significantly reduced in size, thickness, and color in both cases. Thus, we conclude that long-term use of topical 0.5% timolol maleate solution is safe and effective in treating superficial capillary hemangiomas.
Delannoy, Joachim; de Maleprade, Hélène; Clanet, Christophe; Quéré, David
2018-05-31
A superhydrophobic capillary tube immersed in water and brought in contact with the bath surface will be invaded by air, owing to its aerophilicity. We discuss this phenomenon where the ingredients of classical capillary rise are inverted, which leads to noticeable dynamical features. (1) The main regime of air invasion is linear in time, due to the viscous resistance of water. (2) Menisci in tubes with millimetre-size radii strongly oscillate before reaching their equilibrium depth, a consequence of inertia. On the whole, capillary descent provides a broad variety of dynamics where capillary effects, viscous friction and liquid inertia all play a role.
Yamaguchi, Toru
2012-09-01
Drug treatment for osteoporosis is intended to prevent osteoporotic fractures. Physicians should assess fracture risk in patients with diabetes not only by measuring bone mineral density (BMD) but also by taking a fracture history and evaluating prior vertebral fractures using spinal X-rays when starting drug therapy. Accumulating evidence shows that patients with diabetes (DM) have a high risk for fragility fractures independent of BMD. Thus, when DM patients have osteopenia, fracture risk could become higher than non-DM counterparts, and drug therapy should be considered to prevent fragility fractures. The criteria for starting drug treatment to prevent fragility fractures in DM patients, albeit tentative, are shown in this article.
Fragile X--a challenge to models of the mind and to best clinical practice.
Hay, David A
2008-06-01
Cornish et al. (2008, this issue) provide an excellent review of Fragile X a common but very complex cause of intellectual disability. They report on a cohort of such males of normal intelligence quotient (IQ) and socioeconomic status (SES), but who have deficits in selective attention and growing impairment in response inhibition. This paper has theoretical views for our models of the mind and clinical implications for families where Fragile X may never have been considered as a possible cause of some of the problems in male and female family members and possibly as well for other disorders such as attention deficit hyperactivity disorder (ADHD) and autism.
Fragile X mental retardation protein: A paradigm for translational control by RNA-binding proteins.
Chen, Eileen; Joseph, Simpson
2015-07-01
Translational control is a common mechanism used to regulate gene expression and occur in bacteria to mammals. Typically in translational control, an RNA-binding protein binds to a unique sequence in the mRNA to regulate protein synthesis by the ribosomes. Alternatively, a protein may bind to or modify a translation factor to globally regulate protein synthesis by the cell. Here, we review translational control by the fragile X mental retardation protein (FMRP), the absence of which causes the neurological disease, fragile X syndrome (FXS). Copyright © 2015 Elsevier B.V. and Société française de biochimie et biologie Moléculaire (SFBBM). All rights reserved.
Human pluripotent stem cell models of Fragile X syndrome.
Bhattacharyya, Anita; Zhao, Xinyu
2016-06-01
Fragile X syndrome (FXS) is the most common inherited cause of intellectual disability and autism. The causal mutation in FXS is a trinucleotide CGG repeat expansion in the FMR1 gene that leads to human specific epigenetic silencing and loss of Fragile X Mental Retardation Protein (FMRP) expression. Human pluripotent stem cells (PSCs), including human embryonic stem cells (ESCs) and particularly induced PSCs (iPSCs), offer a model system to reveal cellular and molecular events underlying human neuronal development and function in FXS. Human FXS PSCs have been established and have provided insight into the epigenetic silencing of the FMR1 gene as well as aspects of neuronal development. Copyright © 2015 Elsevier Inc. All rights reserved.
Rehm, Roberta S; Rohr, Julie A
2002-10-01
Few studies have focused on school activities of children who are medically fragile/technology-dependent. This article reports on an exploratory, interpretive study that examined the perceptions of parents, nurses, and educators with regard to their school concerns and strategies for ensuring the safety and health of these students. Informants all believed that attending school provided benefits to most children who are medically fragile/technology-dependent, including opportunities for skill acquisition, socialization, and respite care for families. However, they also perceived that there were real risks involved, including obtaining appropriate care, exposure to infection, and social isolation or teasing. Copyright 2002, Elsevier Science (USA). All rights reserved.
Belardi, Katie; Watson, Linda R; Faldowski, Richard A; Hazlett, Heather; Crais, Elizabeth; Baranek, Grace T; McComish, Cara; Patten, Elena; Oller, D Kimbrough
2017-04-01
An infant's vocal capacity develops significantly during the first year of life. Research suggests early measures of pre-speech development, such as canonical babbling and volubility, can differentiate typical versus disordered development. This study offers a new contribution by comparing early vocal development in 10 infants with Fragile X syndrome and 14 with typical development. Results suggest infants with Fragile X syndrome produce fewer syllables and have significantly lower canonical babbling ratios compared to infants who are typically developing. Furthermore, the particular measures of babbling were strong predictors of group membership, adding evidence regarding the possible utility of these markers in early identification.
Preserved entropy and fragile magnetism
Canfield, Paul C.; Bud’ko, Sergey L.
2016-07-05
Here, a large swath of quantum critical and strongly correlated electron systems can be associated with the phenomena of preserved entropy and fragile magnetism. In this overview we present our thoughts and plans for the discovery and development of lanthanide and transition metal based, strongly correlated systems that are revealed by suppressed, fragile magnetism, quantum criticality, or grow out of preserved entropy. We will present and discuss current examples such as YbBiPt, YbAgGe, YbFe 2Zn 20, PrAg 2In, BaFe 2As 2, CaFe 2As 2, LaCrSb 3 and LaCrGe 3 as part of our motivation and to provide illustrative examples.
Development of a Specific Impulse Balance for a Pulsed Capillary Discharge (Preprint)
2008-06-13
thrust stand [rad/s] I. Introduction A capillary discharge based coaxial , electrothermal pulsed plasma thruster (PPT) is currently under...20-23 July 2008. 14. ABSTRACT A capillary discharge based pulsed plasma thruster is currently under development at the Air Force Research...Edwards AFB, CA 93524 A capillary discharge based pulsed plasma thruster is currently under development at the Air Force Research Laboratory. A
Characteristics of a capillary-discharge flash x-ray generator
NASA Astrophysics Data System (ADS)
Sato, Eiichi; Hayasi, Yasuomi; Usuki, Tatsumi; Sato, Koetsu; Takayama, Kazuyoshi; Ido, Hideaki
2002-11-01
The fundamental experiments for measuring soft x-ray characteristics from the vacuum capillary are described. These experiments are primarily performed in order to generate line spectra such as x-ray lasers. The generator consists of a high-voltage power supply, a polarity-inversion ignitron pulse generator, a turbo-molecular pump, and a radiation tube with a capillary. A high-voltage condenser of 0.2 μF in the pulse generator is charged up to 20 kV by the power supply, and the electric charges in the condenser are discharged to the capillary in the tube after closing the ignitron. During the discharge, weakly ionized plasma forms on the inner and outer sides of a capillary. In the present work, the pump evacuates air from the tube with a pressure of about 1 mPa, and a demountable capillary was developed in order to measure x-ray spectra according to changes in the capillary length. In this capillary, the anode (target) and cathode elements can be changed corresponding to the objectives. The capillary diameter is 2.0 mm, and the length is adjusted from 1 to 50 mm. When a capillary with aluminum anode and cathode electrodes was employed, both the cathode voltage and the discharge current almost displayed damp oscillations. The peak values of the voltage and current increased when the charging voltage was increased and their maximum values were -10.8 kV and 4.7 kV, respectively. The x-ray durations observed by a 1.6 μm aluminum filter were less than 30 μs, and we detected the aluminum characteristic x-ray intensity using a 6.8 μm aluminum filter. In the spectrum measurement, two sets of aluminum and titanium electrodes were employed, and we observed multi-line spectra. The line photon energies seldom varied according to changes in teh condenser charging voltage and to changes in the electrode element. In the case where the titanium electrode was employed, the line number decreased with corresponding decreases in the capillary length. Compared with incoherent visible light, these rays from the capillary were diffracted greatly after pass through two slits.
ERIC Educational Resources Information Center
Dissanayake, Cheryl; Bui, Quang; Bulhak-Paterson, Danuta; Huggins, Richard; Loesch, Danuta Z.
2009-01-01
Background: In order to better understand the underlying biological mechanism/s involved in autism, it is important to investigate the cognitive and behavioural phenotypes associated with idiopathic autism (autism without a known cause) and comorbid autism (autism associated with known genetic/biological disorders such as fragile X syndrome).…
ERIC Educational Resources Information Center
Estigarribia, Bruno; Martin, Gary E.; Roberts, Joanne E.
2012-01-01
Purpose: To examine which cognitive, environmental, and speech-language variables predict expressive syntax in boys with fragile X syndrome (FXS), boys with Down syndrome (DS), and typically developing (TD) boys, and whether predictive relationships differed by group. Method: We obtained Index of Productive Syntax ( Scarborough, 1990) scores for…
Mothers' Economic Conditions and Sources of Support in Fragile Families
ERIC Educational Resources Information Center
Kalil, Ariel; Ryan, Rebecca M.
2010-01-01
Rising rates of nonmarital childbirth in the United States have resulted in a new family type, the fragile family. Such families, which include cohabiting couples as well as single mothers, experience significantly higher rates of poverty and material hardship than their married counterparts. Ariel Kalil and Rebecca Ryan summarize the economic…