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Find video protocols related to scientific articles indexed in Pubmed.
The Relationship Between Colonoscopy Procedure Order and Adenoma Detection Rates: A Prospective Study.
J. Clin. Gastroenterol.
PUBLISHED: 10-17-2014
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The aim of this study was to prospectively assess the effects of the order of colonoscopic procedures and other possible factors on the adenoma detection rate (ADR).
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Two-year outcome after combination therapy for polypoidal choroidal vasculopathy: comparison with photodynamic monotherapy and anti-vascular endothelial growth factor monotherapy.
Ophthalmologica
PUBLISHED: 09-17-2014
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To compare treatment outcomes of photodynamic therapy (PDT), anti-vascular endothelial growth factor (VEGF) therapy and PDT combined with anti-VEGF therapy for polypoidal choroidal vasculopathy (PCV).
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MemStar: a one-shot Escherichia coli-based approach for high-level bacterial membrane protein production.
FEBS Lett.
PUBLISHED: 08-28-2014
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Optimising membrane protein production yields in Escherichiacoli can be time- and resource-consuming. Here, we present a simple and effective Membrane protein Single shot amplification recipe: MemStar. This one-shot amplification recipe is based on the E. coli strain Lemo21(DE3), the PASM-5052 auto-induction medium and, contradictorily, an IPTG induction step. Using MemStar, production yields for most bacterial membrane proteins tested were improved to reach an average of 5 mg L(-1) per OD600 unit, which is significantly higher than yields obtained with other common production strategies. With MemStar, we have been able to obtain new structural information for several transporters, including the sodium/proton antiporter NapA.
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Factors that determine prolonged cecal intubation time during colonoscopy: impact of visceral adipose tissue.
Scand. J. Gastroenterol.
PUBLISHED: 08-21-2014
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Various factors including age, sex, body mass index (BMI) and history of operation have been linked to the colonoscopic intubation time. The aims of this study were to identify the factors predicting cecal intubation time (CIT) and to evaluate the effect of the visceral adipose tissue (VAT) area on CIT.
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Structural effects of PrP polymorphisms on intra- and interspecies prion transmission.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 07-17-2014
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Understanding the molecular parameters governing prion propagation is crucial for controlling these lethal, proteinaceous, and infectious neurodegenerative diseases. To explore the effects of prion protein (PrP) sequence and structural variations on intra- and interspecies transmission, we integrated studies in deer, a species naturally susceptible to chronic wasting disease (CWD), a burgeoning, contagious epidemic of uncertain origin and zoonotic potential, with structural and transgenic (Tg) mouse modeling and cell-free prion amplification. CWD properties were faithfully maintained in deer following passage through Tg mice expressing cognate PrP, and the influences of naturally occurring PrP polymorphisms on CWD susceptibility were accurately reproduced in Tg mice or cell-free systems. Although Tg mice also recapitulated susceptibility of deer to sheep prions, polymorphisms that provided protection against CWD had distinct and varied influences. Whereas substitutions at residues 95 and 96 in the unstructured region affected CWD propagation, their protective effects were overridden during replication of sheep prions in Tg mice and, in the case of residue 96, deer. The inhibitory effects on sheep prions of glutamate at residue 226 in elk PrP, compared with glutamine in deer PrP, and the protective effects of the phenylalanine for serine substitution at the adjacent residue 225, coincided with structural rearrangements in the globular domain affecting interaction between ?-helix 3 and the loop between ?2 and ?-helix 2. These structure-function analyses are consistent with previous structural investigations and confirm a role for plasticity of this tertiary structural epitope in the control of PrP conversion and strain propagation.
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Fascia wrapping technique: a modified method for the treatment of cubital tunnel syndrome.
ScientificWorldJournal
PUBLISHED: 07-02-2014
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Variations of the anterior transposition of the ulnar nerve for cubital tunnel syndrome include subcutaneous, submuscular, intramuscular, and subfascial methods. We introduce a modification of subfascial transposition, which is designed to facilitate nerve gliding by wrapping the nerve with fascia. Twenty patients with wrapping surgery following the diagnosis of cubital tunnel syndrome were reviewed retrospectively. Preoperative electrodiagnostic studies were performed in all patients and all of them were rechecked postoperatively. The preoperative mean value of motor conduction velocity (MCV) was 37.1 ± 6.7?m/s within the elbow segment and this result showed a decrease compared to the result of MCV with 53.9 ± 6.9?m/s in the below the elbow-wrist segment with statistical significance (P < 0.05). Postoperative mean values of MCV were improved in all of 20 patients to 47.6 ± 5.5?m/s (P < 0.05). 19 patients of 20 (95%) reported good or excellent clinical outcomes according to a modified Bishop scoring system. The surgical treatment methods for cubital tunnel syndrome have their own advantages and disadvantages, and the preferred method differs depending on the surgeon. The wrapping method of anterior transposition is a newly designed alternative method modified from subfascial transposition. This method could be an alternative option to treat cubital tunnel syndrome.
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Parental somatic mosaicism is underrecognized and influences recurrence risk of genomic disorders.
Am. J. Hum. Genet.
PUBLISHED: 05-15-2014
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New human mutations are thought to originate in germ cells, thus making a recurrence of the same mutation in a sibling exceedingly rare. However, increasing sensitivity of genomic technologies has anecdotally revealed mosaicism for mutations in somatic tissues of apparently healthy parents. Such somatically mosaic parents might also have germline mosaicism that can potentially cause unexpected intergenerational recurrences. Here, we show that somatic mosaicism for transmitted mutations among parents of children with simplex genetic disease is more common than currently appreciated. Using the sensitivity of individual-specific breakpoint PCR, we prospectively screened 100 families with children affected by genomic disorders due to rare deletion copy-number variants (CNVs) determined to be de novo by clinical analysis of parental DNA. Surprisingly, we identified four cases of low-level somatic mosaicism for the transmitted CNV in DNA isolated from parental blood. Integrated probabilistic modeling of gametogenesis developed in response to our observations predicts that mutations in parental blood increase recurrence risk substantially more than parental mutations confined to the germline. Moreover, despite the fact that maternally transmitted mutations are the minority of alleles, our model suggests that sexual dimorphisms in gametogenesis result in a greater proportion of somatically mosaic transmitting mothers who are thus at increased risk of recurrence. Therefore, somatic mosaicism together with sexual differences in gametogenesis might explain a considerable fraction of unexpected recurrences of X-linked recessive disease. Overall, our results underscore an important role for somatic mosaicism and mitotic replicative mutational mechanisms in transmission genetics.
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Reconstructing the evolutionary origins and phylogeography of hantaviruses.
Trends Microbiol.
PUBLISHED: 04-17-2014
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Rodents have long been recognized as the principal reservoirs of hantaviruses. However, with the discovery of genetically distinct and phylogenetically divergent lineages of hantaviruses in multiple species of shrews, moles, and insectivorous bats from widely separated geographic regions, a far more complex landscape of hantavirus host distribution, evolution, and phylogeography is emerging. Detailed phylogenetic analyses, based on partial and full-length genomes of previously described rodent-borne hantaviruses and newly detected non-rodent-borne hantaviruses, indicate an Asian origin and support the emerging concept that ancestral non-rodent mammals may have served as the hosts of primordial hantaviruses.
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Expanded host diversity and geographic distribution of hantaviruses in sub-Saharan Africa.
J. Virol.
PUBLISHED: 04-16-2014
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The recent discovery of hantaviruses in shrews and bats in West Africa suggests that other genetically distinct hantaviruses exist in East Africa. Genetic and phylogenetic analyses of newfound hantaviruses, detected in archival tissues from the Geata mouse shrew (Myosorex geata) and Kilimanjaro mouse shrew ( Myosorex zinki) captured in Tanzania, expands the host diversity and geographic distribution of hantaviruses and suggests that ancestral shrews and/or bats may have served as the original mammalian hosts of primordial hantaviruses.
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Long-term progression of retinal vasculitis in Behçet patients using a fluorescein angiography scoring system.
Graefes Arch. Clin. Exp. Ophthalmol.
PUBLISHED: 04-07-2014
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To evaluate the long-time progression of retinal vasculitis in Behçet patients using the fluorescein angiography (FA) scoring system.
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Quinacrine promotes replication and conformational mutation of chronic wasting disease prions.
Proc. Natl. Acad. Sci. U.S.A.
PUBLISHED: 04-07-2014
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Quinacrine's ability to reduce levels of pathogenic prion protein (PrP(Sc)) in mouse cells infected with experimentally adapted prions led to several unsuccessful clinical studies in patients with prion diseases, a 10-y investment to understand its mechanism of action, and the production of related compounds with expectations of greater efficacy. We show here, in stark contrast to this reported inhibitory effect, that quinacrine enhances deer and elk PrP(Sc) accumulation and promotes propagation of prions causing chronic wasting disease (CWD), a fatal, transmissible, neurodegenerative disorder of cervids of uncertain zoonotic potential. Surprisingly, despite increased prion titers in quinacrine-treated cells, transmission of the resulting prions produced prolonged incubation times and altered PrP(Sc) deposition patterns in the brains of diseased transgenic mice. This unexpected outcome is consistent with quinacrine affecting the intrinsic properties of the CWD prion. Accordingly, quinacrine-treated CWD prions were comprised of an altered PrP(Sc) conformation. Our findings provide convincing evidence for drug-induced conformational mutation of prions without the prerequisite of generating drug-resistant variants of the original strain. More specifically, they show that a drug capable of restraining prions in one species/strain setting, and consequently used to treat human prion diseases, improves replicative ability in another and therefore force reconsideration of current strategies to screen antiprion compounds.
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Dopaminergic neuron destruction reduces hippocampal serotonin 1A receptor uptake of trans-[(18)F]Mefway.
Appl Radiat Isot
PUBLISHED: 03-25-2014
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The purpose of the present study is to investigate the relationship between dopaminergic neuron destruction and 5-HT system changes in a hemiparkinsonian rat model. We performed PET imaging studies with trans-[(18)F]Mefway in a hemiparkinsonian model of unilateral 6-hydroxydopamine (6-OHDA) rats. Region-of-interests (ROIs) were drawn in the hippocampus (HP) and cerebellum (CB). HP uptake, the ratios of specific binding to non-specific binding in the HP, and non-displaceable binding potential (BPND) in the HP were compared between 6-OHDA and control rats. As a result, unilateral 6-OHDA-lesioned rats exhibited significant bilateral reduction of HP uptake and trans-[(18)F]Mefway BPND compared to the intact control group. Therefore, the results demonstrate that destruction of the dopaminergic system causes the reduction of the serotonergic system.
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Visual outcome and prognostic factors after surgery for a secondary epiretinal membrane associated with branch retinal vein occlusion.
Graefes Arch. Clin. Exp. Ophthalmol.
PUBLISHED: 03-18-2014
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To assess the visual outcome and prognostic factors after surgery for a secondary epiretinal membrane (ERM) due to branch retinal vein occlusion (BRVO).
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6q22.1 microdeletion and susceptibility to pediatric epilepsy.
Eur. J. Hum. Genet.
PUBLISHED: 03-04-2014
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Genomic copy-number variations (CNVs) constitute an important cause of epilepsies and other human neurological disorders. Recent advancement of technologies integrating genome-wide CNV mapping and sequencing is rapidly expanding the molecular field of pediatric neurodevelopmental disorders. In a previous study, a novel epilepsy locus was identified on 6q16.3q22.31 by linkage analysis in a large pedigree. Subsequent array comparative genomic hybridization (array CGH) analysis of four unrelated cases narrowed this region to ?5?Mb on 6q22.1q22.31. We sought to further narrow the critical region on chromosome 6q22. Array CGH analysis was used in genome-wide screen for CNVs of a large cohort of patients with neurological abnormalities. Long-range PCR and DNA sequencing were applied to precisely map chromosomal deletion breakpoints. Finally, real-time qPCR was used to estimate relative expression in the brain of the candidate genes. We identified six unrelated patients with overlapping microdeletions within 6q22.1q22.31 region, three of whom manifested seizures. Deletions were found to be de novo in 5/6 cases, including all subjects presenting with seizures. We sequenced the deletion breakpoints in four patients and narrowed the critical region to a ?250-kb segment at 6q22.1 that includes NUS1, several expressed sequence tags (ESTs) that are highly expressed in the brain, and putative regulatory sequences of SLC35F1. Our findings indicate that dosage alteration in particular, of NUS1, EST AI858607, or SLC35F1 are important contributors to the neurodevelopmental phenotype associated with 6q22 deletion, including epilepsy and tremors.European Journal of Human Genetics advance online publication, 14 May 2014; doi:10.1038/ejhg.2014.75.
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Reversal of early central retinal vein occlusion by alleviating optic nerve edema with an intravitreal dexamethasone implant.
Korean J Ophthalmol
PUBLISHED: 02-06-2014
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This case describes the reversal of early central retinal vein occlusion (CRVO) with disc swelling after intravitreal dexamethasone implant (Ozurdex) injection. A 44-year-old female presented with sudden-onset intermittent blurred vision in her left eye. Fundus examination revealed multiple retinal hemorrhages without macular edema (ME). Two weeks later, an increased number of retinal hemorrhages with severe disc swelling were noted with still no sign of ME. An intravitreal dexamethasone implant was injected. Five days later, there were improvements in disc swelling and retinal hemorrhage. One month later, her subjective visual symptoms were completely improved, and fundus examination revealed marked improvement along with almost complete resolution of disc swelling. Intravitreal dexamethasone implant injection may potentially change the natural course of CRVO progression and its various subsequent complications.
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Acute physical stress induces the alteration of the serotonin 1A receptor density in the hippocampus.
Synapse
PUBLISHED: 02-05-2014
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Stress affects the serotonergic system, which is associated with depression. Previous research has showed that chronic stress causes the deactivation of the limbic system. However, the influence of the acute physical stress on the serotonergic system in vivo was primarily unclear. The purpose of this research is to elucidate the effects of the acute physical stress in vivo using PET. For quantification of the 5-HT1A receptors in the brain, we measured [(18)F]Mefway uptake in the two experiment groups (control and despair rats). The despair group was subjected to the external stressful situation (i.e., forced swimming) and total duration time of immobility, refers to the despair severity, and was analyzed. In the intercomparison experiment, the resulting PET images of [(18)F]Mefway in the despair rat displayed a significant reduction of radioactivity in the hippocampus (HP) compared with the control. The nondisplaceable binding potential (BPND ) refers to the ratio of the concentration of radioligand in the receptor-rich region (i.e., HP) to the concentration of that in the receptor-free region (i.e., cerebellum). The hippocampal uptake and the BPND in the despair group were respectively about 25 and 18% lower than those of the control group. The ratio of specific binding to nonspecific binding in the despair group was 18% lower than that of the control. In the intracomparison experiments, the BPND and immobility in the despair group showed a strong negative correlation. Taken together, the data illustrates that an acute physical stress induces the change in the serotonergic system that correlates with the behavioral despair.
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Delineation of candidate genes responsible for structural brain abnormalities in patients with terminal deletions of chromosome 6q27.
Eur. J. Hum. Genet.
PUBLISHED: 01-29-2014
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Patients with terminal deletions of chromosome 6q present with structural brain abnormalities including agenesis of corpus callosum, hydrocephalus, periventricular nodular heterotopia, and cerebellar malformations. The 6q27 region harbors genes that are important for the normal development of brain and delineation of a critical deletion region for structural brain abnormalities may lead to a better genotype-phenotype correlation. We conducted a detailed clinical and molecular characterization of seven unrelated patients with deletions involving chromosome 6q27. All patients had structural brain abnormalities. Using array comparative genomic hybridization, we mapped the size, extent, and genomic content of these deletions. The smallest region of overlap spans 1.7?Mb and contains DLL1, THBS2, PHF10, and C6orf70 (ERMARD) that are plausible candidates for the causation of structural brain abnormalities. Our study reiterates the importance of 6q27 region in normal development of brain and helps identify putative genes in causation of structural brain anomalies.European Journal of Human Genetics advance online publication, 16 April 2014; doi:10.1038/ejhg.2014.51.
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Relaxin augments BMP-2-induced osteoblast differentiation and bone formation.
J. Bone Miner. Res.
PUBLISHED: 01-26-2014
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Relaxin (Rln), a polypeptide hormone of the insulin superfamily, is an ovarian peptide hormone that is involved in a diverse range of physiological and pathological reactions. In this study, we investigated the effect of Rln on bone morphogenetic protein 2 (BMP-2)-induced osteoblast differentiation and bone formation. Expression of Rln receptors was examined in the primary mouse bone marrow stem cells (BMSCs) and mouse embryonic fibroblast cell line C3H/10T1/2 cells by RT-PCR and Western blot during BMP-2-induced osteoblast differentiation. The effect of Rln on osteoblast differentiation and mineralization was evaluated by measuring the alkaline phosphatase activity, osteocalcin production, and Alizarin red S staining. For the in vivo evaluation, BMP-2 and/or Rln were administered with type I collagen into the back of mice, and after 3 weeks, bone formation was analyzed by micro-computed tomography (µCT). Western blot was performed to determine the effect of Rln on osteoblast differentiation-related signaling pathway. Expression of Rxfp 1 in BMSCs and C3H/10T1/2 cells was significantly increased by BMP-2. In vitro, Rln augmented BMP-2-induced alkaline phosphatase expression, osteocalcin production, and matrix mineralization in BMSCs and C3H/10T1/2 cells. In addition, in vivo administration of Rln enhanced BMP-2-induced bone formation in a dose-dependent manner. Interestingly, Rln synergistically increased and sustained BMP-2-induced Smad, p38, and transforming growth factor-? activated kinase (TAK) 1 phosphorylation. BMP-2-induced Runx 2 expression and activity were also significantly augmented by Rln. These results show that Rln enhanced synergistically BMP-2-induced osteoblast differentiation and bone formation through its receptor, Rxfp 1, by augmenting and sustaining BMP-2-induced Smad and p38 phosphorylation, which upregulate Runx 2 expression and activity. These results suggest that Rln might be useful for therapeutic application in destructive bone diseases.
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Subfoveal choroidal thickness as a potential predictor of visual outcome and treatment response after intravitreal ranibizumab injections for typical exudative age-related macular degeneration.
Am. J. Ophthalmol.
PUBLISHED: 01-21-2014
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To investigate the prognostic implication of subfoveal choroidal thickness on treatment outcome after intravitreal ranibizumab injections for typical exudative age-related macular degeneration (AMD).
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A slow-forming isopeptide bond in the structure of the major pilin SpaD from Corynebacterium diphtheriae has implications for pilus assembly.
Acta Crystallogr. D Biol. Crystallogr.
PUBLISHED: 01-20-2014
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The Gram-positive organism Corynebacterium diphtheriae, the cause of diphtheria in humans, expresses pili on its surface which it uses for adhesion and colonization of its host. These pili are covalent protein polymers composed of three types of pilin subunit that are assembled by specific sortase enzymes. A structural analysis of the major pilin SpaD, which forms the polymeric backbone of one of the three types of pilus expressed by C. diphtheriae, is reported. Mass-spectral and crystallographic analysis shows that SpaD contains three internal Lys-Asn isopeptide bonds. One of these, shown by mass spectrometry to be located in the N-terminal D1 domain of the protein, only forms slowly, implying an energy barrier to bond formation. Two crystal structures, of the full-length three-domain protein at 2.5 Å resolution and of a two-domain (D2-D3) construct at 1.87 Å resolution, show that each of the three Ig-like domains contains a single Lys-Asn isopeptide-bond cross-link, assumed to give mechanical stability as in other such pili. Additional stabilizing features include a disulfide bond in the D3 domain and a calcium-binding loop in D2. The N-terminal D1 domain is more flexible than the others and, by analogy with other major pilins of this type, the slow formation of its isopeptide bond can be attributed to its location adjacent to the lysine used in sortase-mediated polymerization during pilus assembly.
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Clinical and spectral-domain optical coherence tomography findings in patients with focal choroidal excavation.
Ophthalmology
PUBLISHED: 01-16-2014
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To describe the clinical and spectral-domain optical coherence tomography (SD-OCT) findings in patients with focal choroidal excavation (FCE).
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Differential regulation of estrogen receptor ? expression in breast cancer cells by metastasis-associated protein 1.
Cancer Res.
PUBLISHED: 01-10-2014
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Metastasis-associated protein 1 (MTA1) is a component of the nucleosome remodeling and histone deacetylase (HDAC) complex, which plays an important role in progression of breast cancer. Although MTA1 is known as a repressor of the transactivation function of estrogen receptor ? (ER?), its involvement in the epigenetic control of transcription of the ER? gene ESR1 has not been studied. Here, we show that silencing of MTA1 reduced the level of expression of ER? in ER?-positive cells but increased it in ER?-negative cells. In both MCF7 and MDA-MB-231, MTA1 was recruited to the region +146 to +461 bp downstream of the transcription start site of ESR1 (ERpro315). Proteomics analysis of the MTA1 complex that was pulled down by an oligonucleotide encoding ERpro315 revealed that the transcription factor AP-2? (TFAP2C) and the IFN-?-inducible protein 16 (IFI16) were components of the complex. Interestingly, in MCF7, TFAP2C activated the reporter encoding ERpro315 and the level of ER? mRNA. By contrast, in MDA-MB-231, IFI16 repressed the promoter activity and silencing of MTA1 increased expression of ER?. Importantly, class II HDACs are involved in the MTA1-mediated differential regulation of ER?. Finally, an MDA-MB-231-derived cell line that stably expressed shIFI16 or shMTA1 was more susceptible to tamoxifen-induced growth inhibition in in vitro and in vivo experiments. Taken together, our findings suggest that the MTA1-TFAP2C or the MTA1-IFI16 complex may contribute to the epigenetic regulation of ESR1 expression in breast cancer and may determine the chemosensitivity of tumors to tamoxifen therapy in patients with breast cancer.
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Hantaviruses: rediscovery and new beginnings.
Virus Res.
PUBLISHED: 01-08-2014
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Virus and host gene phylogenies, indicating that antigenically distinct hantaviruses (family Bunyaviridae, genus Hantavirus) segregate into clades, which parallel the molecular evolution of rodents belonging to the Murinae, Arvicolinae, Neotominae and Sigmodontinae subfamilies, suggested co-divergence of hantaviruses and their rodent reservoirs. Lately, this concept has been vigorously contested in favor of preferential host switching and local host-specific adaptation. To gain insights into the host range, spatial and temporal distribution, genetic diversity and evolutionary origins of hantaviruses, we employed reverse transcription-polymerase chain reaction to analyze frozen, RNAlater(®)-preserved and ethanol-fixed tissues from 1546 shrews (9 genera and 47 species), 281 moles (8 genera and 10 species) and 520 bats (26 genera and 53 species), collected in Europe, Asia, Africa and North America during 1980-2012. Thus far, we have identified 24 novel hantaviruses in shrews, moles and bats. That these newfound hantaviruses are geographically widespread and genetically more diverse than those harbored by rodents suggests that the evolutionary history of hantaviruses is far more complex than previously conjectured. Phylogenetic analyses indicate four distinct clades, with the most divergent comprising hantaviruses harbored by the European mole and insectivorous bats, with evidence for both co-divergence and host switching. Future studies will provide new knowledge about the transmission dynamics and pathogenic potential of these newly discovered, still-orphan, non-rodent-borne hantaviruses.
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Somatic mosaicism detected by exon-targeted, high-resolution aCGH in 10,362 consecutive cases.
Eur. J. Hum. Genet.
PUBLISHED: 01-08-2014
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Somatic chromosomal mosaicism arising from post-zygotic errors is known to cause several well-defined genetic syndromes as well as contribute to phenotypic variation in diseases. However, somatic mosaicism is often under-diagnosed due to challenges in detection. We evaluated 10,362 patients with a custom-designed, exon-targeted whole-genome oligonucleotide array and detected somatic mosaicism in a total of 57 cases (0.55%). The mosaicism was characterized and confirmed by fluorescence in situ hybridization (FISH) and/or chromosome analysis. Different categories of abnormal cell lines were detected: (1) aneuploidy, including sex chromosome abnormalities and isochromosomes (22 cases), (2) ring or marker chromosomes (12 cases), (3) single deletion/duplication copy number variations (CNVs) (11 cases), (4) multiple deletion/duplication CNVs (5 cases), (5) exonic CNVs (4 cases), and (6) unbalanced translocations (3 cases). Levels of mosaicism calculated based on the array data were in good concordance with those observed by FISH (10-93%). Of the 14 cases evaluated concurrently by chromosome analysis, mosaicism was detected solely by the array in 4 cases (29%). In summary, our exon-targeted array further expands the diagnostic capability of high-resolution array comparative genomic hybridization in detecting mosaicism for cytogenetic abnormalities as well as small CNVs in disease-causing genes.
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Unrelated donor cord blood transplantation for non-malignant disorders in children and adolescents.
Pediatr Transplant
PUBLISHED: 11-22-2013
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This study analyzes the data reported to the Korean Cord Blood Registry between 1994 and 2008, involving children and adolescents with non-malignant diseases. Sixty-five patients were evaluated in this study: SAA (n = 24), iBMFS, (n = 16), and primary immune deficiency/inherited metabolic disorder (n = 25). The CI of neutrophil recovery was 73.3% on day 42. By day 100, the CI of acute grade II-IV graft-versus-host disease was 32.3%. At a median follow-up of 71 months, five-yr OS was 50.7%. The survival rate (37.5%) and CI of neutrophil engraftment (37.5%) were lowest in patients with iBMFS. Deaths were mainly due to infection, pulmonary complications, and hemorrhage. In a multivariate analysis, the presence of >3.91 × 10(5) /kg of infused CD34 +  cells was the only factor consistently identified as significantly associated with neutrophil engraftment (p = 0.04) and OS (p = 0.03). UCBT using optimal cell doses appears to be a feasible therapy for non-malignant diseases in children and adolescents for whom there is no appropriate HLA-matched related donor. Strategies to reduce transplant-related toxicities would improve the outcomes of UCBT in non-malignant diseases.
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Epigenetic dominance of prion conformers.
PLoS Pathog.
PUBLISHED: 10-01-2013
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Although they share certain biological properties with nucleic acid based infectious agents, prions, the causative agents of invariably fatal, transmissible neurodegenerative disorders such as bovine spongiform encephalopathy, sheep scrapie, and human Creutzfeldt Jakob disease, propagate by conformational templating of host encoded proteins. Once thought to be unique to these diseases, this mechanism is now recognized as a ubiquitous means of information transfer in biological systems, including other protein misfolding disorders such as those causing Alzheimers and Parkinsons diseases. To address the poorly understood mechanism by which host prion protein (PrP) primary structures interact with distinct prion conformations to influence pathogenesis, we produced transgenic (Tg) mice expressing different sheep scrapie susceptibility alleles, varying only at a single amino acid at PrP residue 136. Tg mice expressing ovine PrP with alanine (A) at (OvPrP-A136) infected with SSBP/1 scrapie prions propagated a relatively stable (S) prion conformation, which accumulated as punctate aggregates in the brain, and produced prolonged incubation times. In contrast, Tg mice expressing OvPrP with valine (V) at 136 (OvPrP-V136) infected with the same prions developed disease rapidly, and the converted prion was comprised of an unstable (U), diffusely distributed conformer. Infected Tg mice co-expressing both alleles manifested properties consistent with the U conformer, suggesting a dominant effect resulting from exclusive conversion of OvPrP-V136 but not OvPrP-A136. Surprisingly, however, studies with monoclonal antibody (mAb) PRC5, which discriminates OvPrP-A136 from OvPrP-V136, revealed substantial conversion of OvPrP-A136. Moreover, the resulting OvPrP-A136 prion acquired the characteristics of the U conformer. These results, substantiated by in vitro analyses, indicated that co-expression of OvPrP-V136 altered the conversion potential of OvPrP-A136 from the S to the otherwise unfavorable U conformer. This epigenetic mechanism thus expands the range of selectable conformations that can be adopted by PrP, and therefore the variety of options for strain propagation.
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Cost-effectiveness of Koreas National Cervical Cancer Screening Program.
Asian Pac. J. Cancer Prev.
PUBLISHED: 09-03-2013
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Cervical cancer, which is common in developing countries, is also a major health issue in Korea. Our aim was to evaluate the cost-effectiveness of Koreas National Cancer Screening Program (NCSP), implemented in 1999.
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Fusion of large-scale genomic knowledge and frequency data computationally prioritizes variants in epilepsy.
PLoS Genet.
PUBLISHED: 09-01-2013
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Curation and interpretation of copy number variants identified by genome-wide testing is challenged by the large number of events harbored in each personal genome. Conventional determination of phenotypic relevance relies on patterns of higher frequency in affected individuals versus controls; however, an increasing amount of ascertained variation is rare or private to clans. Consequently, frequency data have less utility to resolve pathogenic from benign. One solution is disease-specific algorithms that leverage gene knowledge together with variant frequency to aid prioritization. We used large-scale resources including Gene Ontology, protein-protein interactions and other annotation systems together with a broad set of 83 genes with known associations to epilepsy to construct a pathogenicity score for the phenotype. We evaluated the score for all annotated human genes and applied Bayesian methods to combine the derived pathogenicity score with frequency information from our diagnostic laboratory. Analysis determined Bayes factors and posterior distributions for each gene. We applied our method to subjects with abnormal chromosomal microarray results and confirmed epilepsy diagnoses gathered by electronic medical record review. Genes deleted in our subjects with epilepsy had significantly higher pathogenicity scores and Bayes factors compared to subjects referred for non-neurologic indications. We also applied our scores to identify a recently validated epilepsy gene in a complex genomic region and to reveal candidate genes for epilepsy. We propose a potential use in clinical decision support for our results in the context of genome-wide screening. Our approach demonstrates the utility of integrative data in medical genomics.
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Lack of Polypoidal Lesions in Patients with Myopic Choroidal Neovascularization as Evaluated by Indocyanine Green Angiography.
Am. J. Ophthalmol.
PUBLISHED: 07-14-2013
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To investigate the prevalence of polypoidal choroidal vasculopathy (PCV) in patients with myopic choroidal neovascularization (CNV) using indocyanine green angiography (ICGA).
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Comparison of detection and miss rates of narrow band imaging, flexible spectral imaging chromoendoscopy and white light at screening colonoscopy: a randomised controlled back-to-back study.
Gut
PUBLISHED: 07-12-2013
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Virtual chromoendoscopy (CE) is expected to enhance adenoma yield and reduce variation in performance between colonoscopists. This study aimed to compare the efficacy of narrow band imaging (NBI), flexible spectral imaging CE (FICE) and white light (WL) colonoscopy and their impact for less experienced endoscopists.
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Characteristics of rhegmatogenous retinal detachment after refractive surgery: Comparison with myopic eyes with retinal detachment.
Am. J. Ophthalmol.
PUBLISHED: 07-11-2013
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To evaluate the characteristics of rhegmatogenous retinal detachment (RD) in patients with previous laser in-situ keratomileusis (LASIK) and compared them to RD in patients with previous laser assisted sub-epithelial keratomileusis (LASEK) and myopic patients with no previous refractive surgery.
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Combined photodynamic therapy with intravitreal bevacizumab injections for polypoidal choroidal vasculopathy: long-term visual outcome.
Am. J. Ophthalmol.
PUBLISHED: 07-11-2013
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To evaluate the long-term visual outcome after combination therapy of photodynamic therapy (PDT) with intravitreal bevacizumab injections for polypoidal choroidal vasculopathy (PCV).
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Ankle neurothekeoma: a case report.
J Foot Ankle Surg
PUBLISHED: 06-18-2013
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Neurothekeoma is a rare, benign, cutaneous tumor of nerve sheath origin that is also termed benign nerve sheath myxoma. This tumor is usually asymptomatic and grows slowly. Neurothekeoma is typically found in young adults and seldom occurs in children. It is most commonly located in the head, neck, and upper extremity and extremely rarely found in the lower leg. We report a rare case of ankle neurothekeoma in a child, with a review of the related published data.
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A case of esophageal candidiasis in an adolescent who had frequently received budesonide nebulizing therapy.
Pediatr Gastroenterol Hepatol Nutr
PUBLISHED: 06-16-2013
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Corticosteroid (budesonide) nebulizer therapy is commonly performed. Its side effects have been considered as being safe or ignorable. The authors present a case of esophageal candidiasis in a healthy female adolescent who was treated with budesonide nebulizer therapy a few times for a cough during the previous winter season. This child presented with dysphagia and epigastric pain for 1 month. Esophageal endoscopy showed a whitish creamy pseudomembrane and erosions on the esophageal mucosa. Pathologic findings showed numerous candidal hyphae. She did not show any evidence of immunodeficiency, clinically and historically. The esophageal lesion did not resolve naturally. The esophageal lesion completely improved with the antifungal therapy for 2 weeks; the symptoms disappeared, and the patient returned to normal health. It is important that frequent esophageal exposure to topical corticosteroids application can cause unexpected side effects.
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Cost-effectiveness outcomes of the national gastric cancer screening program in South Korea.
Asian Pac. J. Cancer Prev.
PUBLISHED: 06-04-2013
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Although screening is necessary where gastric cancer is particularly common in Asia, the performance outcomes of mass screening programs have remained unclear. This study was conducted to evaluate cost-effectiveness outcomes of the national cancer screening program (NCSP) for gastric cancer in South Korea.
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The National Cancer Screening Program for breast cancer in the Republic of Korea: is it cost-effective?
Asian Pac. J. Cancer Prev.
PUBLISHED: 05-18-2013
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This goal of this research was to evaluate the cost-effectiveness of the National Cancer Screening Program (NCSP) for breast cancer in the Republic of Korea from a government expenditure perspective. In 2002-2003 (baseline), a total of 8,724,860 women aged 40 years or over were invited to attend breast cancer screening by the NCSP. Those who attended were identified using the NCSP database, and women were divided into two groups, women who attended screening at baseline (screened group) and those who did not (non-screened group). Breast cancer diagnosis in both groups at baseline, and during 5-year follow-up was identified using the Korean Central Cancer Registry. The effectiveness of the NCSP for breast cancer was estimated by comparing 5-year survival and life years saved (LYS) between the screened and the unscreened groups, measured using mortality data from the Korean National Health Insurance Corporation and the National Health Statistical Office. Direct screening costs, indirect screening costs, and productivity costs were considered in different combinations in the model. When all three of these costs were considered together, the incremental cost to save one life year of a breast cancer patient was 42,305,000 Korean Won (KW) (1 USD=1,088 KW) for the screened group compared to the non-screened group. In sensitivity analyses, reducing the false-positive rate of the screening program by half was the most cost-effective (incremental cost-effectiveness ratio, ICER=30,110,852 KW/LYS) strategy. When the upper age limit for screening was set at 70 years, it became more cost-effective (ICER=39,641,823 KW/LYS) than when no upper age limit was set. The NCSP for breast cancer in Korea seems to be accepted as cost-effective as ICER estimates were around the Gross Domestic Product. However, cost-effectiveness could be further improved by increasing the sensitivity of breast cancer screening and by setting appropriate age limits.
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NAHR-mediated copy-number variants in a clinical population: mechanistic insights into both genomic disorders and Mendelizing traits.
Genome Res.
PUBLISHED: 05-08-2013
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We delineated and analyzed directly oriented paralogous low-copy repeats (DP-LCRs) in the most recent version of the human haploid reference genome. The computationally defined DP-LCRs were cross-referenced with our chromosomal microarray analysis (CMA) database of 25,144 patients subjected to genome-wide assays. This computationally guided approach to the empirically derived large data set allowed us to investigate genomic rearrangement relative frequencies and identify new loci for recurrent nonallelic homologous recombination (NAHR)-mediated copy-number variants (CNVs). The most commonly observed recurrent CNVs were NPHP1 duplications (233), CHRNA7 duplications (175), and 22q11.21 deletions (DiGeorge/velocardiofacial syndrome, 166). In the ?25% of CMA cases for which parental studies were available, we identified 190 de novo recurrent CNVs. In this group, the most frequently observed events were deletions of 22q11.21 (48), 16p11.2 (autism, 34), and 7q11.23 (Williams-Beuren syndrome, 11). Several features of DP-LCRs, including length, distance between NAHR substrate elements, DNA sequence identity (fraction matching), GC content, and concentration of the homologous recombination (HR) hot spot motif 5-CCNCCNTNNCCNC-3, correlate with the frequencies of the recurrent CNVs events. Four novel adjacent DP-LCR-flanked and NAHR-prone regions, involving 2q12.2q13, were elucidated in association with novel genomic disorders. Our study quantitates genome architectural features responsible for NAHR-mediated genomic instability and further elucidates the role of NAHR in human disease.
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Expression of semaphorin 3A and neuropilin 1 in asthma.
J. Korean Med. Sci.
PUBLISHED: 05-07-2013
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Neuropilin 1 (NP1) is a part of essential receptor complexes mediating both semaphorin3A (SEMA3A) and vascular endothelial growth factor (VEGF) which is one of important mediators involved in the pathogenesis of asthma. Therefore, it is possible that SEMA3A plays a role in the pathogenesis of asthma through attenuation of VEGF-mediated effects. In the present study, we aimed to evaluate expression levels of SEMA3A and NP1 using induced sputum of asthmatics and a murine model of asthma. Firstly, SEMA3A and NP1 expressions in induced sputum of asthmatics and SEMA3A and NP1 expression on bronchoalveolar lavage (BAL) cells and lung homogenates of asthmatic mice were determined. Then we evaluated the immunolocalization of VEGF receptor 1 (VEGFR1), VEGF receptor 2 (VEGFR2), and NP1 expressions on asthmatic mice lung tissue and their subcellular distributions using fibroblast and BEAS2B cell lines. Sputum SEMA3A and NP1 expressions were significantly higher in asthmatics than controls. Similarly, SEMA3A and NP1 expressions on BAL cells and lung homogenates were significantly elevated in asthmatic mice compared to control mice. Immunohistochemical analysis showed that VEGFR1, VEGFR2, and NP1 expressions were also uniformly increased in asthmatic mice. Our observations suggest that SEMA3A and NP1 may play important roles in the pathogenesis of asthma.
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An arm-swapped dimer of the Streptococcus pyogenes pilin specific assembly factor SipA.
J. Struct. Biol.
PUBLISHED: 04-26-2013
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Streptococcus pyogenes (group A streptococcus [GAS]) is a major human pathogen. Attachment of GAS to host cells depends in large part on pili. These assemblies are built from multiple covalently linked subunits of a backbone protein (FctA), which forms the shaft of the pilus, and two minor pilin proteins, FctB anchoring the pilus to the cell wall and Cpa functioning as the adhesin at the tip. Polymerisation of the pilin subunits is mediated by a specific sortase, which catalyzes the formation of peptide bonds linking successive subunits. An additional gene, SipA, is also essential for GAS pilus polymerisation, but its function remains undefined. Here we report the crystal structure of a truncated SipA protein from GAS, determined at 1.67Å resolution. The structure reveals that SipA has the same core fold as the Escherichia coli type-I signal peptidase (SPase-I), but has a much smaller non-catalytic domain. The truncated protein, which lacks 9 N-terminal residues, forms an arm-swapped dimer in which the C-terminal ?-strand of each monomer crosses over to interact with an N-terminal strand from the other monomer. In addition, there is no peptide binding cleft and significant differences in the putative membrane association region.
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Focal adhesion linker proteins expression of fibroblast related to adhesion in response to different transmucosal abutment surfaces.
J Adv Prosthodont
PUBLISHED: 04-24-2013
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To evaluate adherence of human gingival fibroblasts (HGFs) to transmucosal abutment of dental implant with different surface conditions with time and to investigate the roles of focal adhesion linker proteins (FALPs) involved in HGFs adhesion to abutment surfaces.
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Ocular risk factors for recurrence of myopic choroidal neovascularization: long-term follow-up study.
Retina (Philadelphia, Pa.)
PUBLISHED: 04-18-2013
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To investigate factors associated with long-term recurrence of myopic choroidal neovascularization (CNV) after treatment with photodynamic therapy (PDT) and/or intravitreal antivascular endothelial growth factor injections.
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Molecular cloning and functional characterization of an endo-?-1,3-glucanase from Streptomyces matensis ATCC 23935.
Food Chem
PUBLISHED: 03-26-2013
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A gene encoding an endo-?-1,3-glucanase from Streptomyces matensis ATCC 23935 (Sm?G) was characterised by cloning and expressing it in Escherichiacoli. The purified enzyme produced ?-1,3-glucooligosaccharides, mainly laminaripentaose, from insoluble curdlan. The optimum pH and temperature were 6.0 and 55°C, respectively. Sm?G inhibited the growth of Candida albicans, which indicates that this enzyme could be potentially used as an anti-fungal agent to control invasive Candida infections. The results suggest that Sm?G may be a useful bioavailable ?-1,3-glucanase.
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Boginia virus, a newfound hantavirus harbored by the Eurasian water shrew (Neomys fodiens) in Poland.
Virol. J.
PUBLISHED: 03-03-2013
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Guided by decades-old reports of hantaviral antigens in the Eurasian common shrew (Sorex araneus) and the Eurasian water shrew (Neomys fodiens) in European Russia, we employed RT-PCR to analyze lung tissues of soricine shrews, captured in Boginia, Huta D?utowska and Kurowice in central Poland during September 2010, 2011 and 2012.
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Long-term visual outcome and prognostic factors after intravitreal ranibizumab injections for polypoidal choroidal vasculopathy.
Am. J. Ophthalmol.
PUBLISHED: 02-27-2013
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To evaluate long-term visual outcome and investigate the prognostic factors after anti-vascular endothelial growth factor (VEGF) therapy for polypoidal choroidal vasculopathy (PCV).
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A two-domain elevator mechanism for sodium/proton antiport.
Nature
PUBLISHED: 02-04-2013
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Sodium/proton (Na(+)/H(+)) antiporters, located at the plasma membrane in every cell, are vital for cell homeostasis. In humans, their dysfunction has been linked to diseases, such as hypertension, heart failure and epilepsy, and they are well-established drug targets. The best understood model system for Na(+)/H(+) antiport is NhaA from Escherichia coli, for which both electron microscopy and crystal structures are available. NhaA is made up of two distinct domains: a core domain and a dimerization domain. In the NhaA crystal structure a cavity is located between the two domains, providing access to the ion-binding site from the inward-facing surface of the protein. Like many Na(+)/H(+) antiporters, the activity of NhaA is regulated by pH, only becoming active above pH?6.5, at which point a conformational change is thought to occur. The only reported NhaA crystal structure so far is of the low pH inactivated form. Here we describe the active-state structure of a Na(+)/H(+) antiporter, NapA from Thermus thermophilus, at 3?Å resolution, solved from crystals grown at pH?7.8. In the NapA structure, the core and dimerization domains are in different positions to those seen in NhaA, and a negatively charged cavity has now opened to the outside. The extracellular cavity allows access to a strictly conserved aspartate residue thought to coordinate ion binding directly, a role supported here by molecular dynamics simulations. To alternate access to this ion-binding site, however, requires a surprisingly large rotation of the core domain, some 20° against the dimerization interface. We conclude that despite their fast transport rates of up to 1,500?ions?per second, Na(+)/H(+) antiporters operate by a two-domain rocking bundle model, revealing themes relevant to secondary-active transporters in general.
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Combined array CGH plus SNP genome analyses in a single assay for optimized clinical testing.
Eur. J. Hum. Genet.
PUBLISHED: 01-28-2013
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In clinical diagnostics, both array comparative genomic hybridization (array CGH) and single nucleotide polymorphism (SNP) genotyping have proven to be powerful genomic technologies utilized for the evaluation of developmental delay, multiple congenital anomalies, and neuropsychiatric disorders. Differences in the ability to resolve genomic changes between these arrays may constitute an implementation challenge for clinicians: which platform (SNP vs array CGH) might best detect the underlying genetic cause for the disease in the patient? While only SNP arrays enable the detection of copy number neutral regions of absence of heterozygosity (AOH), they have limited ability to detect single-exon copy number variants (CNVs) due to the distribution of SNPs across the genome. To provide comprehensive clinical testing for both CNVs and copy-neutral AOH, we enhanced our custom-designed high-resolution oligonucleotide array that has exon-targeted coverage of 1860 genes with 60?000 SNP probes, referred to as Chromosomal Microarray Analysis - Comprehensive (CMA-COMP). Of the 3240 cases evaluated by this array, clinically significant CNVs were detected in 445 cases including 21 cases with exonic events. In addition, 162 cases (5.0%) showed at least one AOH region >10?Mb. We demonstrate that even though this array has a lower density of SNP probes than other commercially available SNP arrays, it reliably detected AOH events >10?Mb as well as exonic CNVs beyond the detection limitations of SNP genotyping. Thus, combining SNP probes and exon-targeted array CGH into one platform provides clinically useful genetic screening in an efficient manner.
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Helicobacter pylori seropositivity in diabetic patients is associated with microalbuminuria.
World J. Gastroenterol.
PUBLISHED: 01-18-2013
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To investigate the relationship between Helicobacter pylori (H. pylori) seropositivity and the presence of microalbuminuria.
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Expanding the genotype-phenotype correlation in subtelomeric 19p13.3 microdeletions using high resolution clinical chromosomal microarray analysis.
Am. J. Med. Genet. A
PUBLISHED: 01-09-2013
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Structural rearrangements of chromosome 19p are rare, and their resulting phenotypic consequences are not well defined. This is the first study to report a cohort of eight patients with subtelomeric 19p13.3 microdeletions, identified using clinical chromosomal microarray analysis (CMA). The deletion sizes ranged from 0.1 to 0.86?Mb. Detailed analysis of the patients clinical features has enabled us to define a constellation of clinical abnormalities that include growth delay, multiple congenital anomalies, global developmental delay, learning difficulties, and dysmorphic facial features. There are eight genes in the 19p13.3 region that may potentially contribute to the clinical phenotype via haploinsufficiency. Moreover, in silico genomic analysis of 19p13.3 microdeletion breakpoints revealed numerous highly repetitive sequences, suggesting LINEs/SINEs-mediated events in generating these microdeletions. Thus, subtelomeric 19p13.3 appears important for normal embryonic and childhood development. The clinical description of patients with deletions in this genomic interval will assist clinicians to identify and treat individuals with similar deletions. © 2013 Wiley Periodicals, Inc.
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Breaking the barriers in membrane protein crystallography.
Int. J. Biochem. Cell Biol.
PUBLISHED: 01-03-2013
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As we appreciate the importance of stabilising membrane proteins, the barriers towards their structure determination are being broken down. This change in mindset comes hand-in-hand with more effort placed on developing methods focused at screening for membrane proteins which are naturally stable in detergent solution or improving those that are not so. In practice, however, it is not easy to decide the best strategy to monitor and improve detergent stability, requiring a decision-making process that can be even more difficult for those new to the field. In this review we outline the importance of membrane protein stability with discussions of the stabilisation strategies applied in context with the use of crystallisation scaffolds and the different types of crystallisation methods themselves. Where possible we also highlight areas that we think could push this field forward with emerging technologies, such as X-ray free electron lasers (X-feL), which could have a big impact on the membrane protein structural biology community. We hope this review will serve as a useful guide for those striving to solve structures of both pro- and eukaryotic membrane proteins.
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Hantaan virus surveillance targeting small mammals at Dagmar North Training Area, Gyeonggi Province, Republic of Korea, 2001-2005.
J. Vector Ecol.
PUBLISHED: 12-02-2011
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In response to a hemorrhagic fever with renal syndrome case in November 2000, a seasonal rodent-borne disease surveillance program was initiated at Dagmar North Training Area (DNTA), Gyeonggi Province, Republic of Korea. From April 2001-December 2005, 1,848 small mammals were captured. Apodemus agrarius accounted for 92.5%, followed by Mus musculus (3.6%), Crocidura lasiura (2.1%), and Microtus fortis (1.1%). Three species of rodents were found to be antibody-positive (Ab+) for Hantaan virus (HTNV): A. agrarius (22.3%), M. musculus (9.1%), and M. fortis (5.0%). Ab+ rates for A. agrarius increased with increasing weight (age), except for those weighing <10 g. The peak HTNV transmission period in Korea coincided with the peak reproductive potential of A. agrarius during the fall (August/September) surveys. HTNV strains from DNTA were distinct from HTNV strains from the Peoples Republic of China. From these studies, more accurate risk assessments can be developed to better protect personnel from rodent-borne diseases.
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Differential expression of cyclophilin A and EMMPRIN in developing molars of rats.
Anat Rec (Hoboken)
PUBLISHED: 09-14-2011
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A complex and intricate cascade of gene expression is essential for late stage tooth development. This study was performed to detect molecules involved in dental hard tissue formation and tooth eruption by comparing gene expression in cap stage molar germs (before eruptive movement and dental hard tissue formation) with that in root formation stage molar germs (after eruptive movement and dental hard tissue formation). DD-PCR revealed that cyclophilin A (Cyp-A), a potent chemoattractant for monocytes as well as a ligand for extracellular matrix metalloproteinase inducer (EMMPRIN) was expressed differentially in the two stages molar germs. The levels of Cyp-A and EMMPRIN mRNA were significantly higher at the root formation stage than at the cap and crown stages of the molar germs. Immunofluorescence showed that Cyp-A and EMMPRIN were expressed strongly in the follicular cells overlaying the occlusal region of the molar germs at the root formation stage. In contrast, their immunoreactivity was weak in the follicular tissues and was not region-specific in molar germs at the cap stage. In addition, the MCP-1 and CSF-1 mRNA levels increased in parallel to that of Cyp-A mRNA and the increased number of osteoclasts at the occlusal region. Immunoreactivity against Cyp-A and EMMPRIN was also observed in the fully differentiated ameloblasts and odontoblasts. This study suggests that Cyp-A and EMMPRIN play roles in the maturation of dental hard tissue and the formation of an eruption pathway.
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Short report: Genetic diversity of Thottapalayam virus, a Hantavirus harbored by the Asian house shrew (Suncus murinus) in Nepal.
Am. J. Trop. Med. Hyg.
PUBLISHED: 09-08-2011
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Despite the recent discovery of genetically divergent hantaviruses in shrews of multiple species in widely separated geographic regions, data are unavailable about the genetic diversity and phylogeography of Thottapalayam virus (TPMV), a hantavirus originally isolated from an Asian house shrew (Suncus murinus) captured in southern India more than four decades ago. To bridge this knowledge gap, the S, M, and L segments of hantavirus RNA were amplified by reverse transcription polymerase chain reaction from archival lung tissues of Asian house shrews captured in Nepal from January to September 1996. Pair-wise alignment and comparison revealed approximately 80% nucleotide and > 94% amino acid sequence similarity to prototype TPMV. Phylogenetic analyses, generated by maximum likelihood and Bayesian methods, showed geographic-specific clustering of TPMV, similar to that observed for rodent- and soricid-borne hantaviruses. These findings confirm that the Asian house shrew is the natural reservoir of TPMV and suggest a long-standing virus-host relationship.
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A case of pediatric idiopathic intracranial hypertension presenting with divergence insufficiency.
Korean J Ophthalmol
PUBLISHED: 07-22-2011
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An 11-year-old female presenting diplopia only at distance was found to have comitant esotropia of 20 prism diopters (PD) at distance and normal alignment at nearer proximity. Other ocular movement, including abduction, was normal and a thorough neurologic examination was also normal. The deviation angle of esotropia was increased to 35 PD in 6 months, and a brain magnetic resonance imaging with venogram at that time demonstrated no intracranial lesion. A lumbar puncture showed increased opening pressure but the cerebrospinal fluid composition was normal. The patient was diagnosed as having idiopathic intracranial hypertension and treated with oral acetazolamide. Three months after treatment, the deviation angle decreased to 10 PD. This is a case report of divergence insufficiency in pediatric idiopathic intracranial hypertension, with an increasing deviation angle of esotropia. Although sixth cranial nerve palsy is a common neurologic manifestation in intracranial hypertension, clinicians should be aware of the possibility of divergence insufficiency. Also, ophthalmoparesis may not be apparent and typical at first presentation, as seen in this case, and therefore ophthalmologists should be aware of this fact, while conducting careful and proper evaluation, follow-up, and intervention.
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Late-onset Citrobacter koseri endophthalmitis with suture exposure after secondary intraocular lens implantation.
Korean J Ophthalmol
PUBLISHED: 07-22-2011
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A 54-year-old male patient was seen in clinic for ocular pain and decreased vision in the right eye with duration of two days. He underwent a cataract operation for his right eye 12 years ago, then a sclera-fixated secondary intraocular implantation and pars plana vitrectomy three years ago due to intraocular lens dislocation. At the initial visit, his visual acuity was restricted to the perception of hand motion. An edematous cornea, cells, flare with hypopyon, and exposed suture material at were observed at the six oclock direction by slit lamp. Vitreous opacity was noted from B-scan ultrasonography. The patient was diagnosed with late-onset endophthalmitis and an intravitreal cocktail injection was done. On the next day, the hypopyon was aggravated, and therefore a pars plana vitrectomy was performed. A vitreous culture tested positive for Citrobacter koseri. After 12 weeks, the best corrected visual acuity of the right eye improved to 0.7 and a fundus examination revealed a relatively normal optic disc and retinal vasculature. We herein report the first case of endophthalmitis caused by Citrobacter koseri in Korea. Exposed suture material was suspected as the source of infection in this case and prompt surgical intervention resulted in a relatively good visual outcome.
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Molecular evolution of Azagny virus, a newfound hantavirus harbored by the West African pygmy shrew (Crocidura obscurior) in Côte dIvoire.
Virol. J.
PUBLISHED: 06-22-2011
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Tanganya virus (TGNV), the only shrew-associated hantavirus reported to date from sub-Saharan Africa, is harbored by the Thereses shrew (Crocidura theresae), and is phylogenetically distinct from Thottapalayam virus (TPMV) in the Asian house shrew (Suncus murinus) and Imjin virus (MJNV) in the Ussuri white-toothed shrew (Crocidura lasiura). The existence of myriad soricid-borne hantaviruses in Eurasia and North America would predict the presence of additional hantaviruses in sub-Saharan Africa, where multiple shrew lineages have evolved and diversified.
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Ecological surveillance of small mammals at Dagmar North Training Area, Gyeonggi Province, Republic of Korea, 2001-2005.
J. Vector Ecol.
PUBLISHED: 06-04-2011
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A seasonal rodent-borne disease surveillance program was established at Dagmar North Training Area located near the demilitarized zone, Republic of Korea, from 2001 through 2005. Selected habitats surveyed included earthen banks separating rice paddies, fighting positions along a 5 m rock-faced earthen berm, and extensive tall grasses with various degrees of herbaceous and scrub vegetation associated with dirt roads, rice paddies, ditches, ponds, or the Imjin River. Of the nine species of small mammals captured, the striped field mouse (Apodemus agrarius), the primary reservoir for Hantaan virus, was the most frequently collected, representing 92.5% of the 1,848 small mammals captured. Males were captured similarly to females during the spring and summer seasons but were captured less frequently during the fall and winter seasons. Gravid rates were highest in the fall (25.5-57.3%) with the lowest rates during the summer (0.0-2.2%). Capture rates were the lowest along earthen banks separating rice paddies (5.5%) and highest in unmanaged tall grasses and crawling vegetation (15.3-43.5%). An increased knowledge of ecological factors that impact the abundance and distribution of small mammals and the associated ectoparasites and pathogens they harbor is critical for developing accurate disease risk assessments and mitigation strategies for preventing vector- and rodent-borne diseases among soldiers training in field environments.
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Shared ancestry between a newfound mole-borne hantavirus and hantaviruses harbored by cricetid rodents.
J. Virol.
PUBLISHED: 06-01-2011
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Discovery of genetically distinct hantaviruses in multiple species of shrews (order Soricomorpha, family Soricidae) and moles (family Talpidae) contests the conventional view that rodents (order Rodentia, families Muridae and Cricetidae) are the principal reservoir hosts and suggests that the evolutionary history of hantaviruses is far more complex than previously hypothesized. We now report on Rockport virus (RKPV), a hantavirus identified in archival tissues of the eastern mole (Scalopus aquaticus) collected in Rockport, TX, in 1986. Pairwise comparison of the full-length S, M, and L genomic segments indicated moderately low sequence similarity between RKPV and other soricomorph-borne hantaviruses. Phylogenetic analyses, using maximum-likelihood and Bayesian methods, showed that RKPV shared a most recent common ancestor with cricetid-rodent-borne hantaviruses. Distributed widely across the eastern United States, the fossorial eastern mole is sympatric and syntopic with cricetid rodents known to harbor hantaviruses, raising the possibility of host-switching events in the distant past. Our findings warrant more-detailed investigations on the dynamics of spillover and cross-species transmission of present-day hantaviruses within communities of rodents and moles.
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Recurrent deletions and reciprocal duplications of 10q11.21q11.23 including CHAT and SLC18A3 are likely mediated by complex low-copy repeats.
Hum. Mutat.
PUBLISHED: 05-17-2011
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We report 24 unrelated individuals with deletions and 17 additional cases with duplications at 10q11.21q21.1 identified by chromosomal microarray analysis. The rearrangements range in size from 0.3 to 12 Mb. Nineteen of the deletions and eight duplications are flanked by large, directly oriented segmental duplications of >98% sequence identity, suggesting that nonallelic homologous recombination (NAHR) caused these genomic rearrangements. Nine individuals with deletions and five with duplications have additional copy number changes. Detailed clinical evaluation of 20 patients with deletions revealed variable clinical features, with developmental delay (DD) and/or intellectual disability (ID) as the only features common to a majority of individuals. We suggest that some of the other features present in more than one patient with deletion, including hypotonia, sleep apnea, chronic constipation, gastroesophageal and vesicoureteral refluxes, epilepsy, ataxia, dysphagia, nystagmus, and ptosis may result from deletion of the CHAT gene, encoding choline acetyltransferase, and the SLC18A3 gene, mapping in the first intron of CHAT and encoding vesicular acetylcholine transporter. The phenotypic diversity and presence of the deletion in apparently normal carrier parents suggest that subjects carrying 10q11.21q11.23 deletions may exhibit variable phenotypic expressivity and incomplete penetrance influenced by additional genetic and nongenetic modifiers.
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Chromosome catastrophes involve replication mechanisms generating complex genomic rearrangements.
Cell
PUBLISHED: 05-17-2011
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Complex genomic rearrangements (CGRs) consisting of two or more breakpoint junctions have been observed in genomic disorders. Recently, a chromosome catastrophe phenomenon termed chromothripsis, in which numerous genomic rearrangements are apparently acquired in one single catastrophic event, was described in multiple cancers. Here, we show that constitutionally acquired CGRs share similarities with cancer chromothripsis. In the 17 CGR cases investigated, we observed localization and multiple copy number changes including deletions, duplications, and/or triplications, as well as extensive translocations and inversions. Genomic rearrangements involved varied in size and complexities; in one case, array comparative genomic hybridization revealed 18 copy number changes. Breakpoint sequencing identified characteristic features, including small templated insertions at breakpoints and microhomology at breakpoint junctions, which have been attributed to replicative processes. The resemblance between CGR and chromothripsis suggests similar mechanistic underpinnings. Such chromosome catastrophic events appear to reflect basic DNA metabolism operative throughout an organisms life cycle.
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High frequency of known copy number abnormalities and maternal duplication 15q11-q13 in patients with combined schizophrenia and epilepsy.
BMC Med. Genet.
PUBLISHED: 05-04-2011
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Many copy number variants (CNVs) are documented to be associated with neuropsychiatric disorders, including intellectual disability, autism, epilepsy, schizophrenia, and bipolar disorder. Chromosomal deletions of 1q21.1, 3q29, 15q13.3, 22q11.2, and NRXN1 and duplications of 15q11-q13 (maternal), 16p11, and 16p13.3 have the strongest association with schizophrenia. We hypothesized that cases with both schizophrenia and epilepsy would have a higher frequency of disease-associated CNVs and would represent an enriched sample for detection of other mutations associated with schizophrenia.
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Gene expression pattern in transmitochondrial cytoplasmic hybrid cells harboring type 2 diabetes-associated mitochondrial DNA haplogroups.
PLoS ONE
PUBLISHED: 03-23-2011
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Decreased mitochondrial function plays a pivotal role in the pathogenesis of type 2 diabetes mellitus (T2DM). Recently, it was reported that mitochondrial DNA (mtDNA) haplogroups confer genetic susceptibility to T2DM in Koreans and Japanese. Particularly, mtDNA haplogroup N9a is associated with a decreased risk of T2DM, whereas haplogroups D5 and F are associated with an increased risk. To examine functional consequences of these haplogroups without being confounded by the heterogeneous nuclear genomic backgrounds of different subjects, we constructed transmitochondrial cytoplasmic hybrid (cybrid) cells harboring each of the three haplogroups (N9a, D5, and F) in a background of a shared nuclear genome. We compared the functional consequences of the three haplogroups using cell-based assays and gene expression microarrays. Cell-based assays did not detect differences in mitochondrial functions among the haplogroups in terms of ATP generation, reactive oxygen species production, mitochondrial membrane potential, and cellular dehydrogenase activity. However, differential expression and clustering analyses of microarray data revealed that the three haplogroups exhibit a distinctive nuclear gene expression pattern that correlates with their susceptibility to T2DM. Pathway analysis of microarray data identified several differentially regulated metabolic pathways. Notably, compared to the T2DM-resistant haplogroup N9a, the T2DM-susceptible haplogroup F showed down-regulation of oxidative phosphorylation and up-regulation of glycolysis. These results suggest that variations in mtDNA can affect the expression of nuclear genes regulating mitochondrial functions or cellular energetics. Given that impaired mitochondrial function caused by T2DM-associated mtDNA haplogroups is compensated by the nuclear genome, we speculate that defective nuclear compensation, under certain circumstances, might lead to the development of T2DM.
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Delineation of a less than 200 kb minimal deleted region for cardiac malformations on chromosome 7p22.
Am. J. Med. Genet. A
PUBLISHED: 03-20-2011
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Cardiac malformations are commonly seen in individuals with terminal and interstitial deletions involving chromosome band 7p22. Although these malformations represent a significant cause of morbidity, the dosage-sensitive gene(s) that underlie these defects have yet to be identified. In this report, we describe a 16-month-old male with tetralogy of Fallot, bilateral second branchial arch remnants, and mild dysmorphic features. Array comparative genomic hybridization analysis revealed a less than 400 kb interstitial deletion on chromosome 7p22. The deletion was confirmed by real-time quantitative PCR and FISH analyses and was not detected in samples obtained from the childs parents. Molecular data from this de novo deletion, in combination with data from other isolated 7p deletions in the literature, can be used to define a less than 200 kb minimal deleted region for cardiac malformations on 7p22. This minimal deleted region spans all, or portions, of the coding regions of four known genes-MAD1L1, FTSJ2, NUDT1, and SNX8-and may include upstream regulatory elements of EIF3B. It is likely that one or more of these five genes, alone or in combination, plays an important, yet previously uncharacterized, role in cardiac development.
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Relaxin is up-regulated in the rat ovary by orthodontic tooth movement.
Eur. J. Oral Sci.
PUBLISHED: 03-18-2011
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Relaxin (Rln) is an ovarian hormone that stimulates osteoclastic and osteoblastic activities and connective tissue turnover. To investigate the expression of Rln during orthodontic tooth movement, rats were implanted with orthodontic appliances that connected a spring from the upper incisors to the first molar with a 70 cN force. Rats in each group were killed 6, 48, and 144 h after activating the appliance, and the levels of Rln1 and Rln3 expression in the ovary were determined by real-time RT-PCR, northern blots, western blots, and immunofluorescence analyses. The amount of tooth movement induced by the orthodontic force increased in a time-dependent manner. The levels of Rln1 mRNA increased by 12-, 41-, and 263-fold at 6, 48, and 144 h, respectively, after orthodontic tooth movement. The time-dependent increase in the concentration of Rln 1 protein in the ovary was also confirmed by western blotting. Rln 1 was localized in the granulosa cells of the ovarian follicles, and the immunoreactivity against Rln 1 was increased by the movement. In contrast, the concentration of Rln 3 was below the level of detection. The results of this study suggest that local changes in periodontal tissues induced by orthodontic tooth movement may affect Rln1 expression in the ovary. However, further studies are needed to decipher the mechanisms involved and the possible contribution of the increased level of expression of Rln 1 to the tooth movement.
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Concordant or discordant? Imaging-pathology correlation in a sonography-guided core needle biopsy of a breast lesion.
Korean J Radiol
PUBLISHED: 03-03-2011
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An imaging-guided core needle biopsy has been proven to be reliable and accurate for the diagnosis of both benign and malignant diseases of the breast, and has replaced surgical biopsy. However, the possibility of a false-negative biopsy still remains. Imaging-pathology correlation is of critical importance in imaging-guided breast biopsies to detect such a possible sampling error and avoid a delay in diagnosis. We will review five possible categories and corresponding management after performing an imaging-pathology correlation in a sonography-guided core needle biopsy of a breast lesion, as well as illustrate the selected images for each category in conjunction with the pathologic finding. Radiologists should be familiar with the imaging features of various breast pathologies and be able to appropriately correlate imaging findings with pathologic results after a core needle biopsy.
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In vitro amplification of misfolded prion protein using lysate of cultured cells.
PLoS ONE
PUBLISHED: 02-18-2011
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Protein misfolding cyclic amplification (PMCA) recapitulates the prion protein (PrP) conversion process under cell-free conditions. PMCA was initially established with brain material and then with further simplified constituents such as partially purified and recombinant PrP. However, availability of brain material from some species or brain material from animals with certain mutations or polymorphisms within the PrP gene is often limited. Moreover, preparation of native PrP from mammalian cells and tissues, as well as recombinant PrP from bacterial cells, involves time-consuming purification steps. To establish a convenient and versatile PMCA procedure unrestricted to the availability of substrate sources, we attempted to conduct PMCA with the lysate of cells that express cellular PrP (PrP(C)). PrP(Sc) was efficiently amplified with lysate of rabbit kidney epithelial RK13 cells stably transfected with the mouse or Syrian hamster PrP gene. Furthermore, PMCA was also successful with lysate of other established cell lines of neuronal or non-neuronal origins. Together with the data showing that the abundance of PrP(C) in cell lysate was a critical factor to drive efficient PrP(Sc) amplification, our results demonstrate that cell lysate in which PrP(C) is present abundantly serves as an excellent substrate source for PMCA.
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Genetic diversity of Imjin virus in the Ussuri white-toothed shrew (Crocidura lasiura) in the Republic of Korea, 2004-2010.
Virol. J.
PUBLISHED: 02-08-2011
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Recently, Imjin virus (MJNV), a genetically distinct hantavirus, was isolated from lung tissues of the Ussuri white-toothed shrew (Crocidura lasiura) captured near the demilitarized zone in the Republic of Korea. To clarify the genetic diversity of MJNV, partial M- and L-segment sequences were amplified from lung tissues of 12 of 37 (32.4%) anti-MJNV IgG antibody-positive Ussuri white-toothed shrews captured between 2004 and 2010. A 531-nucleotide region of the M segment (coordinates 2,255 to 2,785) revealed that the 12 MJNV strains differed by 0-12.2% and 0-2.3% at the nucleotide and amino acid levels, respectively. A similar degree of nucleotide (0.2-11.9%) and amino acid (0-3.8%) difference was found in a 632-nucleotide length of the L segment (coordinates 962 to 1,593) of nine MJNV strains. Phylogenetic analyses, based on the partial M and L segments of MJNV strains generated by the neighbor-joining and maximum likelihood methods, showed geographic-specific clustering, akin to the phylogeography of rodent-borne hantaviruses.
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A retained lens fragment induced anterior uveitis and corneal edema 15 years after cataract surgery.
Korean J Ophthalmol
PUBLISHED: 01-17-2011
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A 60-year-old male was referred to the ophthalmologic clinic with aggravated anterior uveitis and corneal edema despite the use of topical and systemic steroids. He had undergone cataract surgery in both eyes 15 years previous. Slit lamp examinations revealed a retained lens fragment in the inferior angle of the anterior chamber, with severe corneal edema and mild anterior uveitis. The corneal edema and uveitis subsided following surgical extraction of the lens fragment. That a retained lens fragment caused symptomatic anterior uveitis with corneal edema 15 years after an uneventful cataract surgery is unique. A retained lens fragment should be considered as one of the causes of anterior uveitis in a pseudophakic patient.
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Crystal structure of Spy0129, a Streptococcus pyogenes class B sortase involved in pilus assembly.
PLoS ONE
PUBLISHED: 01-11-2011
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Sortase enzymes are cysteine transpeptidases that mediate the covalent attachment of substrate proteins to the cell walls of gram-positive bacteria, and thereby play a crucial role in virulence, infection and colonisation by pathogens. Many cell-surface proteins are anchored by the housekeeping sortase SrtA but other more specialised sortases exist that attach sub-sets of proteins or function in pilus assembly. The sortase Spy0129, or SrtC1, from the M1 SF370 strain of Streptococcus pyogenes is responsible for generating the covalent linkages between the pilin subunits in the pili of this organism. The crystal structure of Spy0129 has been determined at 2.3 Å resolution (R?=?20.4%, Rfree ?=?26.0%). The structure shows that Spy0129 is a class B sortase, in contrast to other characterised pilin polymerases, which belong to class C. Spy0129 lacks a flap believed to function in substrate recognition in class C enzymes and instead has an elaborated ?6/?7 loop. The two independent Spy0129 molecules in the crystal show differences in the positions and orientations of the catalytic Cys and His residues, Cys221 and His126, correlated with movements of the ?7/?8 and ?4/?5 loops that respectively follow these residues. Bound zinc ions stabilise these alternative conformations in the crystal. This conformational variability is likely to be important for function although there is no evidence that zinc is involved in vivo.
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Observation and prediction of recurrent human translocations mediated by NAHR between nonhomologous chromosomes.
Genome Res.
PUBLISHED: 01-06-2011
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Four unrelated families with the same unbalanced translocation der(4)t(4;11)(p16.2;p15.4) were analyzed. Both of the breakpoint regions in 4p16.2 and 11p15.4 were narrowed to large ?359-kb and ?215-kb low-copy repeat (LCR) clusters, respectively, by aCGH and SNP array analyses. DNA sequencing enabled mapping the breakpoints of one translocation to 24 bp within interchromosomal paralogous LCRs of ?130 kb in length and 94.7% DNA sequence identity located in olfactory receptor gene clusters, indicating nonallelic homologous recombination (NAHR) as the mechanism for translocation formation. To investigate the potential involvement of interchromosomal LCRs in recurrent chromosomal translocation formation, we performed computational genome-wide analyses and identified 1143 interchromosomal LCR substrate pairs, >5 kb in size and sharing >94% sequence identity that can potentially mediate chromosomal translocations. Additional evidence for interchromosomal NAHR mediated translocation formation was provided by sequencing the breakpoints of another recurrent translocation, der(8)t(8;12)(p23.1;p13.31). The NAHR sites were mapped within 55 bp in ?7.8-kb paralogous subunits of 95.3% sequence identity located in the ?579-kb (chr 8) and ?287-kb (chr 12) LCR clusters. We demonstrate that NAHR mediates recurrent constitutional translocations t(4;11) and t(8;12) and potentially many other interchromosomal translocations throughout the human genome. Furthermore, we provide a computationally determined genome-wide "recurrent translocation map."
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What is Visualize?

JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.