bluuebunny/crossref_metadata_2025 huggingface dataset:
Fifteen years and 382 extended right grafts from in situ split livers in a multicenter study: Are these still extended criteria liver grafts?
Authors: Maggi Umberto , De Feo Tullia M. , Andorno Enzo , Cillo Umberto , De Carlis Luciano , Colledan Michele , Burra Patrizia , De Fazio Nicola , Rossi Giorgio ,   on behalf of the Liver Transplantation and Intestine North Italy Transplant Study Group
Published: December 2014

In situ split liver extended right grafts (SL‐ERGs) are still considered marginal grafts. Our aim was to verify this statement at the present time. From 1997 to 2011, a multicenter, retrospective study based on a prospective database was performed at 9 liver transplantation (LT) centers in northern Italy; it included 382 in situ SL‐ERG transplants in adults. There were 358 primary LTs and 24 retransplantations (RETXs). The 1‐, 3‐, and 5‐year overall graft survival rate for LT with in situ SL‐ERGs were 73.5%, 63.3%, and 60.7%, respectively, from 1997 to 2004 and 83.5%, 80.3%, and 80.3%, respectively, thereafter (P = 0.0001). A shorter total ischemia time and fewer RETX grafts were the main differences between the characteristics of the 2 periods. From 1997 to 2011, the 1‐, 3‐, and 5‐year graft survival rates showed a significant difference between the 358 primary LT in situ SL‐ERGs and the 24 RETX in situ SL‐ERGs (P < 0.001). In a multivariate analysis, the main prognostic factor for 60‐day graft survival was a total ischemia time < 8 hours for the 358 primary in situ SL‐ERGs. From 2005 to 2011, in 2473 LTs, the 5‐year graft survival for 184 in situ SL‐ERGs and 2289 whole grafts was 75% and 80% (P = 0.3), respectively. Univariate and multivariate studies alike failed to indicate that the type of graft was a prognostic factor for graft survival. A donor age > 60 years, RETX grafts, and urgency were the main prognostic factors for failure for all of the grafts. Although caution should be taken regarding the choice of appropriate donors, in situ SL‐ERGs should no longer be considered marginal grafts for experienced LT centers. SL‐ERGs should not be used in RETX settings, and when SL‐ERGs are used as primary grafts, the total ischemia time should be less than 8 hours. Liver Transpl 21:500‐511, 2015. © 2015 AASLD.
Morusin inhibits glioblastoma stem cell growth in vitro and in vivo through stemness attenuation, adipocyte transdifferentiation, and apoptosis induction
Authors: Guo Huijie , Liu Chuanlan , Yang Liuqi , Dong Lihua , Wang Li , Wang Qiaoping , Li Haiyan , Zhang Jie , Lin Ping , Wang Xiujie
Published: December 2014

Glioblastoma multiforme (GBM) cancer stem cells (GSCs) are responsible for the progression and recurrence of GBM after conventional therapy. Morusin possesses anti‐cancer activity in vitro. The purpose of this study is to confirm the growth inhibition effect of morusin on human GSCs growth in vitro and in vivo and to explore the possible mechanism of its activity. Human GSCs were enriched under nonadhesive culture system, and characterized through neurosphere formation, toluidine blue staining, immunofluorescence staining, Western blotting analysis of stemness markers of CD133, nestin, Sox2 and Oct4, and tumorigenecity in vivo; the growth inhibition effect of morusin on human GSCs in vitro and in vivo were tested by cell cytotoxicity, neurosphere formation inhibition, adipogenic differentiation, apoptosis induction, and tumor growth inhibition in vivo assays. The potential molecular mechanisms underlying the growth inhibition effect of morusin on GSCs in vitro and in vivo were investigated with Western blotting evaluation of stemness, adipogenic, and apoptotic proteins in morusin treated GSCs and tumor tissues. GSCs enriched under nonadhesive culture system possess stemness characterstics; Morusin inhibited GSCs growth in vitro and in vivo, it reduced stemness of GSCs, induced them adipocyte‐like transdifferention and apoptosis. Morusin has the potential to inhibit human GSCs growth in vitro and in vivo through stemness attenuation, adipocyte transdifferentiation, and apoptosis induction. © 2014 Wiley Periodicals, Inc.
A 7.5‐Mb duplication at chromosome 11q21‐11q22.3 is associated with a novel spastic ataxia syndrome
Authors: Johnson Janel O. , Stevanin Giovanni , van de Leemput Joyce , Hernandez Dena G. , Arepalli Sampath , Forlani Sylvie , Zonozi Reza , Gibbs J. Raphael , Brice Alexis , Durr Alexandra , Singleton Andrew B.
Published: December 2014

Background

The autosomal dominant spinocerebellar ataxias are most commonly caused by nucleotide repeat expansions followed by base‐pair changes in functionally important genes. Structural variation has recently been shown to underlie spinocerebellar ataxia types 15 and 20.

Methods

We applied single‐nucleotide polymorphism (SNP) genotyping to determine whether structural variation causes spinocerebellar ataxia in a family from France.

Results

We identified an approximately 7.5‐megabasepair duplication on chromosome 11q21‐11q22.3 that segregates with disease. This duplication contains an estimated 44 genes. Duplications at this locus were not found in control individuals.

Conclusions

We have identified a new spastic ataxia syndrome caused by a genomic duplication, which we have denoted as spinocerebellar ataxia type 39. Finding additional families with this phenotype will be important to identify the genetic lesion underlying disease. © 2014 International Parkinson and Movement Disorder Society
Parkinson's disease correlates with promoter methylation in the α‐synuclein gene
Authors: Pihlstrøm Lasse , Berge Victoria , Rengmark Aina , Toft Mathias
Published: December 2014

Background

Genome‐wide association studies have demonstrated association between SNCA variability and susceptibility to Parkinson's disease, but causal mechanisms are unclear. We hypothesized that risk variants affect methylation of a putative promoter in SNCA intron 1, previously highlighted in epigenetic studies of Parkinson's disease.

Methods

We analyzed sample sets from blood (n = 72) and cerebral cortex (n = 24) in Parkinson's disease patients and healthy controls. We genotyped SNCA single‐nucleotide polymorphisms, examined messenger RNA (mRNA) expression and assessed intron 1 methylation levels by methylation‐sensitive restriction enzyme digestion and quantitative polymerase chain reaction (PCR).

Results

Patients showed significant hypomethylation as compared with controls in the blood sample set. In addition, rs3756063 was associated with SNCA methylation level in both blood (P = 5.9 × 10−5) and brain (P = 0.023).

Conclusions

Our findings support a link between SNCA variability, promoter methylation, and Parkinson's disease risk and indicate that methylation patterns in brain are mirrored in the blood. SNCA methylation warrants further investigation as a potential biomarker. © 2014 International Parkinson and Movement Disorder Society
Abnormal functional connectivity of the amygdala is associated with depression in Parkinson's disease
Authors: Hu Xiao , Song Xiaopeng , Yuan Yonggui , Li Erfeng , Liu Jiajia , Liu Weiguo , Liu Yijun
Published: December 2014

Depressive symptoms are common in Parkinson's disease (PD), but the pathophysiology and neural basis underlying depression in PD is not well understood. Abnormal functional connectivity of the amygdala with various cortical and subcortical areas has been observed in major depressive disorder, indicating that dysfunction of the corticolimbic network may be involved in the pathogenesis of major depressive disorder. However, little is known about alterations of amygdala functional connectivity in depressed PD patients. In the present study, 20 depressed PD patients, 40 nondepressed PD patients, and 43 matched healthy controls underwent neuropsychological tests and resting‐state functional MRI scanning. Between‐group differences in amygdala functional connectivity network were examined using t tests. Compared to the nondepressed PD patients, depressed PD patients showed increased left amygdala functional connectivity with the bilateral mediodorsal thalamus, right amygdala functional connectivity with the left superior temporal gyrus, and left calcarine gyrus. Compared to the healthy controls, the depressed PD group also showed increased left amygdala functional connectivity with the bilateral mediodorsal thalamus, but decreased left amygdala functional connectivity with the left putamen, left inferior frontal gyrus, and the right cerebellum, as well as decreased right amygdala functional connectivity with the left inferior orbitofrontal gyrus, the left gyrus rectus, and the right putamen. The increased connectivity between limbic regions and decreased connectivity between the corticolimbic networks may reflect impaired high‐order cortical regulatory effects on the emotion‐related limbic areas, which may lead to mood dysregulation. Our study should advance the understanding of neural mechanisms underlying depression in PD. © 2014 International Parkinson and Movement Disorder Society
A population‐based study on combined markers for early Parkinson's disease
Authors: Tunc Sinem , Graf Julia , Tadic Vera , Brüggemann Norbert , Schmidt Alexander , Al‐Khaled Mohamed , Wolff Simone , Vollstedt Eva‐Juliane , Lorwin Anne , Hampf Jennie , Piskol Linda , Klein Christine , Hagenah Johann , Kasten Meike
Published: December 2014

The prerequisite for an earlier diagnosis of Parkinson's disease (PD) are markers that are both sensitive and specific for clinically definite PD and its prediagnosic phases. Promising candidates include enlarged hyperechogenicity of the substantia nigra (SN+) on transcranial sonography (TCS) and hyposmia. However, despite good sensitivity and specificity, both markers have yet failed to yield reliable predictions. We pursue the possibility of combined use in an ongoing population‐based cohort. Subjects were recruited from 10,000 inhabitants of Luebeck/Germany aged 50 to 79 years and additional PD patients from our outpatient clinic. After neurological examination, 715 subjects were grouped into clinically definite PD (n = 106), possible prediagnostic PD (ppPD; n = 73), and a control group subdivided into healthy individuals (n = 283) and controls with diseases other than PD (n = 253). Subjects underwent TCS and smell testing. Sensitivity and specificity of SN+ and hyposmia were good for PD; however, positive predictive values (PPV) of both SN+ (5.2%) and olfaction (2.5%) were low. At least one positive/both positive markers were present in 33%/1% of healthy controls, 33%/2% of diseased controls, 62%/7% of ppPD, and 94%/51% of PD. When combining SN+ and hyposmia, PPV increased to 17.6%, with a sensitivity of 51% and a specificity of 98%. Both SN+ and hyposmia offer good enrichment towards PD and ppPD, are stable against other diseases, and the combination of markers highly increases specificity. However, if the combination of SN+ and hyposmia were used as criterion for PD diagnosis, almost half of clinically definite PD and more than 90% of ppPD would have been missed. © 2014 International Parkinson and Movement Disorder Society
The significance of motor (A)symmetry in Parkinson's disease
Authors: Marinus Johan , van Hilten Jacobus J.
Published: December 2014

This study was undertaken to evaluate whether the predominant motor distribution pattern (ie, symmetric or asymmetric) observed in patients with Parkinson's disease (PD) contributes independently to disease severity and progression. We further examine whether this pattern is stable over time, and whether a potential change in pattern affects the course of the disease. We used data from the longitudinal PROPARK study (N > 400) to examine the association of the predominant motor distribution pattern with motor, cognitive, depressive, psychotic, and autonomic symptoms, and with excessive daytime sleepiness. We found that a symmetrical distribution of motor features was associated with poorer performance on nearly all domains, but that this was entirely explained by confounding, in particular by higher age and longer disease duration. We also found that greater asymmetry was associated with younger age, younger age at onset, and shorter disease duration. We further observed a clear tendency to develop a more symmetric distribution pattern as the disease advanced. Conversion to a symmetric pattern was associated with more severe disease, but this conversion did not contribute independently to the less favorable disease course. With increasing age and disease duration comes a clear tendency to develop a more symmetric distribution of motor features in PD. Although this change in distribution pattern is associated with more severe disease as compared with nonconvertors, this pattern change did not contribute independently to the less favorable course. We discuss these findings in light of the evidence from the literature. © 2014 International Parkinson and Movement Disorder Society
Progression of gait dysfunction in incident Parkinson's disease: Impact of medication and phenotype
Authors: Galna Brook , Lord Sue , Burn David J. , Rochester Lynn
Published: December 2014

Gait impairment in Parkinson's disease (PD) persists despite the use of dopaminergic therapy. Motor phenotype associated with greater postural instability and gait difficulty is related to a greater risk of motor decline and may be influenced by non‐dopaminergic pathology. This study documents the progression of gait impairment over 18 months in an incident cohort of PD with regard to phenotype and medication. Gait characteristics were measured in 121 PD and 184 controls, and 18 months later in 108 PD participants. Sixteen gait characteristics were examined with respect to five broad domains for PD and motor phenotype. Correlations between change in levodopa (l‐dopa) equivalent daily dose and gait were used to identify dopa‐responsive and nonresponsive characteristics. Pace and rhythm deteriorated over 18 months in people with PD, with other gait domains remaining stable. People with a postural instability and gait difficulty phenotype had more impaired gait at baseline compared with a tremor‐dominant phenotype, which was most evident in temporal characteristics. In contrast, pace and variability deteriorated over the subsequent 18 months in the tremor‐dominant phenotype only. Weak but statistically significant correlations were found between increased l‐dopa medication and less deterioration in pace and asymmetry. Significant gait impairment is evident in very early disease despite optimal medication. Change over 18 months is subtle and discrete, and is more pronounced in the tremor‐dominant phenotype. Some features of gait are refractory to dopaminergic therapy, implicating a non‐dopaminergic contribution. This may explain more temporal gait disturbance in the postural instability and gait difficulty phenotype. © 2014 International Parkinson and Movement Disorder Society
Is the Parkinson anxiety scale comparable across raters?
Authors: Forjaz Maria João , Ayala Alba , Martinez‐Martin Pablo , Dujardin Kathy , Pontone Gregory M. , Starkstein Sergio E. , Weintraub Daniel , Leentjens Albert F. G.
Published: December 2014

The Parkinson Anxiety Scale is a new scale developed to measure anxiety severity in Parkinson's disease specifically. It consists of three dimensions: persistent anxiety, episodic anxiety, and avoidance behavior. This study aimed to assess the measurement properties of the scale while controlling for the rater (self‐ vs. clinician‐rated) effect. The Parkinson Anxiety Scale was administered to a cross‐sectional multicenter international sample of 362 Parkinson's disease patients. Both patients and clinicians rated the patient's anxiety independently. A many‐facet Rasch model design was applied to estimate and remove the rater effect. The following measurement properties were assessed: fit to the Rasch model, unidimensionality, reliability, differential item functioning, item local independency, interrater reliability (self or clinician), and scale targeting. In addition, test–retest stability, construct validity, precision, and diagnostic properties of the Parkinson Anxiety Scale were also analyzed. A good fit to the Rasch model was obtained for Parkinson Anxiety Scale dimensions A and B, after the removal of one item and rescoring of the response scale for certain items, whereas dimension C showed marginal fit. Self versus clinician rating differences were of small magnitude, with patients reporting higher anxiety levels than clinicians. The linear measure for Parkinson Anxiety Scale dimensions A and B showed good convergent construct with other anxiety measures and good diagnostic properties. Parkinson Anxiety Scale modified dimensions A and B provide valid and reliable measures of anxiety in Parkinson's disease that are comparable across raters. Further studies are needed with dimension C. © 2014 International Parkinson and Movement Disorder Society
Stem cell reprogramming: Basic implications and future perspective for movement disorders
Authors: Brändl Björn , Schneider Susanne A. , Loring Jeanne F. , Hardy John , Gribbon Philip , Müller Franz‐Josef
Published: December 2014

The introduction of stem cell‐associated molecular factors into human patient‐derived cells allows for their reprogramming in the laboratory environment. As a result, human induced pluripotent stem cells (hiPSC) can now be reprogrammed epigenetically without disruption of their overall genomic integrity. For patients with neurodegenerative diseases characterized by progressive loss of functional neurons, the ability to reprogram any individual's cells and drive their differentiation toward susceptible neuronal subtypes holds great promise. Apart from applications in regenerative medicine and cell replacement–based therapy, hiPSCs are increasingly used in preclinical research for establishing disease models and screening for drug toxicities. The rapid developments in this field prompted us to review recent progress toward the applications of stem cell technologies for movement disorders. We introduce reprogramming strategies and explain the critical steps in the differentiation of hiPSCs to clinical relevant subtypes of cells in the context of movement disorders. We summarize and discuss recent discoveries in this field, which, based on the rapidly expanding basic science literature as well as upcoming trends in personalized medicine, will strongly influence the future therapeutic options available to practitioners working with patients suffering from such disorders. © 2014 International Parkinson and Movement Disorder Society
Selective changes of ocular vestibular myogenic potentials in Parkinson's disease
Authors: Pötter‐Nerger Monika , Govender Sendhil , Deuschl Günther , Volkmann Jens , Colebatch J.G.
Published: December 2014

Background

Vestibular evoked myogenic potentials represent electrophysiological tools to measure vestibular reflex actions at different levels of the brainstem in Parkinson's disease.

Objective

To investigate cervical and ocular vestibular myogenic potentials in Parkinsonian patients with mild disability.

Methods

In 13 Parkinsonian patients and 13 age‐matched healthy controls, cervical and ocular vestibular myogenic potentials were recorded after unilateral air‐conducted tone bursts and bone‐conducted stimuli delivered at the forehead or mastoids.

Results

In contrast to relatively preserved cervical vestibular evoked myogenic potentials, ocular vestibular evoked myogenic potentials were significantly delayed and of reduced amplitude, particularly after impulsive stimulation in Parkinsonian patients. Levodopa had no significant effect on either type of response.

Conclusion

In mild to moderate Parkinson's disease, altered ocular vestibular myogenic potentials may indicate early functional involvement of the upper brainstem, in contrast to preserved lower brainstem function as reflected by normal cervical vestibular myogenic potentials. © 2014 International Parkinson and Movement Disorder Society
A de novoADCY5 mutation causes early‐onset autosomal dominant chorea and dystonia
Authors: Carapito Raphael , Paul Nicodème , Untrau Meiggie , Le Gentil Marion , Ott Louise , Alsaleh Ghada , Jochem Pierre , Radosavljevic Mirjana , Le Caignec Cédric , David Albert , Damier Philippe , Isidor Bertrand , Bahram Seiamak
Published: December 2014

Importance

Apart from Huntington's disease, little is known of the genetics of autosomal dominant chorea associated with dystonia. Here we identify adenylate cyclase 5 (ADCY5) as a likely new causal gene for early‐onset chorea and dystonia.

Observations

Whole exome sequencing in a three‐generation family affected with autosomal dominant chorea associated with dystonia identified a single de novo mutation—c.2088+1G>A in a 5' donor splice‐site of ADCY5—segregating with the disease. This mutation seeming leads to RNA instability and therefore ADCY5 haploinsufficiency.

Conclusions and Relevance

Our finding confirms the genetic/clinical heterogeneity of the disorder; corroborated by previous identification of ADCY5 mutations in one family with dyskinesia‐facial myokymia and in two unrelated sporadic cases of paxoysmal choreic/dystonia‐facial myokymia; ADCY5's high expression in the striatum and movement disorders in ADCY5‐deficient mice. Hence ADCY5 genetic analyses may be relevant in the diagnostic workup of unexplained early‐onset hyperkinetic movement disorders. © 2014 International Parkinson and Movement Disorder Society
Vitamin D from different sources is inversely associated with Parkinson disease
Authors: Wang Liyong , Evatt Marian L. , Maldonado Lizmarie G. , Perry William R. , Ritchie James C. , Beecham Gary W. , Martin Eden R. , Haines Jonathan L. , Pericak‐Vance Margaret A. , Vance Jeffery M. , Scott William K.
Published: December 2014

An inverse association between Parkinson disease (PD) and total vitamin D levels has been reported, but whether vitamin D from different sources, that is, 25(OH)D2 (from diet and supplements) and 25(OH)D3 (mainly from sunlight exposure), all contribute to the association is unknown. Plasma total 25(OH)D, 25(OH)D2, and 25(OH)D3 levels were measured by liquid chromatography–tandem mass spectrometry in PD patients (n = 478) and controls (n = 431). Total 25(OH)D was categorized by clinical insufficiency or deficiency; 25(OH)D2 and 25(OH)D3 were analyzed in quartiles. Vitamin D deficiency (total 25[OH]D < 20 ng/mL) and vitamin D insufficiency (total 25[OH]D < 30 ng/mL) are associated with PD risk (odds ratio [OR] = 2.6 [deficiency] and 2.1 [insufficiency]; P < 0.0001), adjusting for age, sex, and sampling season. Both 25(OH)D2 and 25(OH)D3 levels are inversely associated with PD (Ptrend < 0.0001). The association between 25(OH)D2 and PD risk is largely confined to individuals with low 25(OH)D3 levels (Ptrend = 0.0008 and 0.12 in individuals with 25[OH]D3 < 20 ng/mL and 25[OH]D3 ≥ 20 ng/mL, respectively). Our data confirm the association between vitamin D deficiency and PD, and for the first time demonstrate an inverse association of 25(OH)D2 with PD. Given that 25(OH)D2 concentration is independent of sunlight exposure, this new finding suggests that the inverse association between vitamin D levels and PD is not simply attributable to lack of sunlight exposure in PD patients with impaired mobility. The current study, however, cannot exclude the possibility that gastrointestinal dysfunction, a non‐motor PD symptom, contributes to the lower vitamin D2 levels in PD patients. © 2014 International Parkinson and Movement Disorder Society
Olfactory dysfunction in Parkinson's disease: Positive effect of cigarette smoking
Authors: Sharer James D. , Leon‐Sarmiento Fidias E. , Morley James F. , Weintraub Daniel , Doty Richard L.
Published: December 2014

Background

There is compelling evidence from over 60 epidemiological studies that smoking significantly reduces the risk of Parkinson's disease (PD). In general, those who currently smoke cigarettes, as well as those with a past history of such smoking, have a reduced risk of PD compared to those who have never smoked. Recently it has been suggested that a cardinal nonmotor sensory symptom of PD, olfactory dysfunction, may be less severe in PD patients who smoke than in PD patients who do not, in contrast to the negative effect of smoking on olfaction described in the general population.

Methods

We evaluated University of Pennsylvania Smell Identification Test (UPSIT) scores from 323 PD patients and 323 controls closely matched individually on age, sex, and smoking history (never, past, or current).

Results

Patients exhibited much lower UPSIT scores than did the controls (P < 0.0001). The relative decline in dysfunction of the current PD smokers was less than that of the never‐ and past‐PD smokers (respective Ps = 0.0005 and 0.0019). Female PD patients outperformed their male counterparts by a larger margin than did the female controls (3.66 vs. 1.07 UPSIT points; respective Ps < 0.0001 and 0.06). Age‐related declines in UPSIT scores were generally present (P < 0.0001). No association between the olfactory measure and smoking dose, as indexed by pack‐years, was evident.

Conclusions

PD patients who currently smoke do not exhibit the smoking‐related decline in olfaction observed in non‐PD control subjects who currently smoke. The physiological basis of this phenomenon is yet to be defined. © 2014 International Parkinson and Movement Disorder Society
Ultrasound‐based motion analysis demonstrates bilateral arm hypokinesia during gait in heterozygous PINK1 mutation carriers
Authors: Nürnberger Lucas , Klein Christine , Baudrexel Simon , Roggendorf Julia , Hildner Marcel , Chen Shu , Kang Jun‐Suk , Hilker Rüdiger , Hagenah Johann
Published: December 2014

Carriers of a single heterozygous PINK1 (PTEN‐induced putative kinase 1) gene mutation provide an ideal opportunity to study the development of parkinsonian motor signs from the very beginning. Measuring tools that reliably represent mild motor symptoms could also facilitate the assessment of future neuroprotective therapies and early diagnosis of Parkinson's disease (PD). We investigated nine family members carrying a heterozygous PINK1 mutation in comparison with 25 age‐matched healthy controls. Arm kinematics were quantified during treadmill walking at four different speeds using ultrasound‐based motion analysis. Heterozygous PINK1 mutation carriers showed a bilateral reduction of arm swing amplitudes (P = 0.003) and arm anteversion (P = 0.001), which was more pronounced on the predominantly affected body side but also was present, albeit to a lesser degree, contralaterally (amplitude P = 0.01, anteversion P = 0.002, repeated measures analysis of covariance [rmANCOVA]). Single post‐hoc comparisons revealed similar results for all speeds on both body sides (P < 0.05) except for 2.0 km/h on the less affected side. A single heterozygous mutation in the PINK1 gene is associated with a bilateral dopaminergic dysfunction in this family. Ultrasound‐based three‐dimensional motion analysis of arm swing during gait is a suitable tool to quantify even subtle hypokinesia in mildly affected PINK1 mutation carriers, which tends to be easily overlooked on the less affected body side during clinical examination. Therefore, this technique is a promising application in early stage PD and in at‐risk populations for the disease. © 2014 International Parkinson and Movement Disorder Society
H‐ABC syndrome and DYT4: Variable expressivity or pleiotropy of TUBB4 mutations?
Authors: Erro Roberto , Hersheson Joshua , Ganos Christos , Mencacci Niccoló E. , Stamelou Maria , Batla Amit , Thust Stefanie Catherine , Bras Jose M. , Guerreiro Rita J. , Hardy John , Quinn Niall P. , Houlden Henry , Bhatia Kailash P.
Published: December 2014

Recently, mutations in the TUBB4A gene have been found to underlie hypomyelination with atrophy of the basal ganglia and cerebellum (H‐ABC) syndrome, a rare neurodegenerative disorder of infancy and childhood. TUBB4A mutations also have been described as causative of DYT4 (“hereditary whispering dysphonia”). However, in DYT4, brain imaging has been reported to be normal and, therefore, H‐ABC syndrome and DYT4 have been construed to be different disorders, despite some phenotypic overlap. Hence, the question of whether these disorders reflect variable expressivity or pleiotropy of TUBB4A mutations has been raised. We report four unrelated patients with imaging findings either partially or totally consistent with H‐ABC syndrome, who were found to have TUBB4A mutations. All four subjects had a relatively homogenous phenotype characterized by severe generalized dystonia with superimposed pyramidal and cerebellar signs, and also bulbar involvement leading to complete aphonia and swallowing difficulties, even though one of the cases had an intermediate phenotype between H‐ABC syndrome and DYT4. Genetic analysis of the TUBB4A gene showed one previously described and two novel mutations (c.941C>T; p.Ala314Val and c.900G>T; p.Met300Ile) in the exon 4 of the gene. While expanding the genetic spectrum of H‐ABC syndrome, we confirm its radiological heterogeneity and demonstrate that phenotypic overlap with DYT4. Moreover, reappraisal of previously reported cases would also argue against pleiotropy of TUBB4A mutations. We therefore suggest that H‐ABC and DYT4 belong to a continuous phenotypic spectrum associated with TUBB4A mutations. © 2014 International Parkinson and Movement Disorder Society
Studying macromolecular complex stoichiometries by peptide‐based mass spectrometry
Authors: Wohlgemuth Ingo , Lenz Christof , Urlaub Henning
Published: December 2014

A majority of cellular functions are carried out by macromolecular complexes. A host of biochemical and spectroscopic methods exists to characterize especially protein/protein complexes, however there has been a lack of a universal method to determine protein stoichiometries. Peptide‐based MS, especially as a complementary method to the MS analysis of intact protein complexes, has now been developed to a point where it can be employed to assay protein stoichiometries in a routine manner. While the experimental demands are still significant, peptide‐based MS has been successfully applied to analyze stoichiometries for a variety of protein complexes from very different biological backgrounds. In this review, we discuss the requirements especially for targeted MS acquisition strategies to be used in this context, with a special focus on the interconnected experimental aspects of sample preparation, protein digestion, and peptide stability. In addition, different strategies for the introduction of quantitative peptide standards and their suitability for different scenarios are compared.
C‐terminal juxtamembrane region of full‐length M2 protein forms a membrane surface associated amphipathic helix
Authors: Huang Shenstone , Green Bryan , Thompson Megan , Chen Richard , Thomaston Jessica , DeGrado William F. , Howard Kathleen P.
Published: December 2014

The influenza A M2 protein is a 97‐residue integral membrane protein involved in viral budding and proton conductance. Although crystal and NMR structures exist of truncated constructs of the protein, there is disagreement between models and only limited structural data are available for the full‐length protein. Here, the structure of the C‐terminal juxtamembrane region (sites 50–60) is investigated in the full‐length M2 protein using site‐directed spin‐labeling electron paramagnetic resonance (EPR) spectroscopy in lipid bilayers. Sites 50–60 were chosen for study because this region has been shown to be critical to the role the M2 protein plays in viral budding. Continuous wave EPR spectra and power saturation data in the presence of paramagnetic membrane soluble oxygen are consistent with a membrane surface associated amphipathic helix. Comparison between data from the C‐terminal juxtamembrane region in full‐length M2 protein with data from a truncated M2 construct demonstrates that the line shapes and oxygen accessibilities are remarkably similar between the full‐length and truncated form of the protein.
Structure, activity, and stability of metagenome‐derived glycoside hydrolase family 9 endoglucanase with an N‐terminal Ig‐like domain
Authors: Okano Hiroyuki , Kanaya Eiko , Ozaki Masashi , Angkawidjaja Clement , Kanaya Shigenori
Published: December 2014

A metagenome‐derived glycoside hydrolase family 9 enzyme with an N‐terminal immunoglobulin‐like (Ig‐like) domain, leaf‐branch compost (LC)‐CelG, was characterized and its crystal structure was determined. LC‐CelG did not hydrolyze p‐nitrophenyl cellobioside but hydrolyzed CM‐cellulose, indicating that it is endoglucanase. LC‐CelG exhibited the highest activity at 70°C and >80% of the maximal activity at a broad pH range of 5–9. Its denaturation temperature was 81.4°C, indicating that LC‐CelG is a thermostable enzyme. The structure of LC‐CelG resembles those of CelD from Clostridium thermocellum (CtCelD), Cel9A from Alicyclobacillus acidocaldarius (AaCel9A), and cellobiohydrolase CbhA from C. thermocellum (CtCbhA), which show relatively low (29–31%) amino acid sequence identities to LC‐CelG. Three acidic active site residues are conserved as Asp194, Asp197, and Glu558 in LC‐CelG. Ten of the thirteen residues that form the substrate binding pocket of AaCel9A are conserved in LC‐CelG. Removal of the Ig‐like domain reduced the activity and stability of LC‐CelG by 100‐fold and 6.3°C, respectively. Removal of the Gln40‐ and Asp99‐mediated interactions between the Ig‐like and catalytic domains destabilized LC‐CelG by 5.0°C without significantly affecting its activity. These results suggest that the Ig‐like domain contributes to the stabilization of LC‐CelG mainly due to the Gln40‐ and Asp99‐mediated interactions. Because the LC‐CelG derivative lacking the Ig‐like domain accumulated in Escherichia coli cells mostly in an insoluble form and this derivative accumulated in a soluble form exhibited very weak activity, the Ig‐like domain may be required to make the conformation of the active site functional and prevent aggregation of the catalytic domain.
Synthesizing Environmental Flow Needs Data for Water Management in a Water‐Scarce State: The Arizona Environmental Water Demands Database
Authors: Mott Lacroix K. E. , Xiu B. C. , Nadeau J. B. , Megdal S. B.
Published: December 2014

Water rights for environmental flows are not universal, and oftentimes, legal tools used to incorporate the environment into water management only require new users to consider their impact. It can be difficult to include the needs of riparian and aquatic ecosystems in new plans when relevant information is not always available, especially when other existing uses already outstrip available supplies. There is a need for easily accessible and understandable science on the water requirements for riparian and aquatic species, so managers can make informed decisions about whether or not to include riparian and aquatic species in their community's water management future. In this paper, we describe the current understanding of the link between hydrology and Arizona's riparian and aquatic ecosystems through the creation of a geospatial Environmental Water Demands database that can be used to determine the water needs to maintain habitat. Analysis of 121 studies reveals that there are very few analyses of the surface water and groundwater requirements for intermittent or ephemeral river systems, and there are only limited generalizable data for aquatic species. Except for a few species, such as Cottonwood (Populous fremontii) and Willow (Salix gooddingii), few data are available on the flow requirements for vegetation. The Environmental Water Demands database can be used to identify critical geographic and topical knowledge gaps where further research is needed, as well as serve as a single place for water and land managers to assess and use the most currently available information to make more informed management decisions and recommendations. Copyright © 2014 John Wiley & Sons, Ltd.
Signalling Through Retinoic Acid Receptors is Required for Reprogramming of Both Mouse Embryonic Fibroblast Cells and Epiblast Stem Cells to Induced Pluripotent Stem Cells
Authors: Yang Jian , Wang Wei , Ooi Jolene , Campos Lia S. , Lu Liming , Liu Pentao
Published: December 2014

We previously demonstrated that coexpressing retinoic acid (RA) receptor gamma and liver receptor homolog-1 (LRH1 or NR5A2) with OCT4, MYC, KLF4, and SOX2 (4F) rapidly reprograms mouse embryonic fibroblast cells (MEFs) into induced pluripotent stem cells (iPSCs). Here, we further explore the role of RA in reprogramming and report that the six factors (6F) efficiently and directly reprogram MEFs into integration-free iPSCs in defined medium (N2B27) in the absence of feeder cells. Through genetic and chemical approaches, we find that RA signalling is essential, in a highly dose-sensitive manner, for MEF reprogramming. The removal of exogenous RA from N2B27, the inhibition of endogenous RA synthesis or the expression of a dominant-negative form of RARA severely impedes reprogramming. By contrast, supplementing N2B27 with various retinoids substantially boosts reprogramming. In addition, when coexpressed with LRH1, RA receptors (RARs) can promote reprogramming in the absence of both exogenous and endogenously synthesized RA. Remarkably, the reprogramming of epiblast stem cells into embryonic stem cell-like cells also requires low levels of RA, which can modulate Wnt signalling through physical interactions of RARs with β-catenin. These results highlight the important functions of RA signalling in reprogramming somatic cells and primed stem cells to naïve pluripotency. Stem Cells  2015;33:1390–1404
Contrasting Roles for C/EBPα and Notch in Irradiation-Induced Multipotent Hematopoietic Progenitor Cell Defects
Authors: Fleenor Courtney Jo , Rozhok Andrii Ivan , Zaberezhnyy Vadym , Mathew Divij , Kim Jihye , Tan Aik-Choon , Bernstein Irwin David , DeGregori James
Published: December 2014

Ionizing radiation (IR) is associated with reduced hematopoietic function and increased risk of hematopoietic malignancies, although the mechanisms behind these relationships remain poorly understood. Both effects of IR have been commonly attributed to the direct induction of DNA mutations, but evidence supporting these hypotheses is largely lacking. Here we demonstrate that IR causes long-term, somatically heritable, cell-intrinsic reductions in hematopoietic stem cell (HSC) and multipotent hematopoietic progenitor cell (mHPC) self-renewal that are mediated by C/EBPα and reversed by Notch. mHPC from previously irradiated (>9 weeks prior), homeostatically restored mice exhibit gene expression profiles consistent with their precocious differentiation phenotype, including decreased expression of HSC-specific genes and increased expression of myeloid program genes (including C/EBPα). These gene expression changes are reversed by ligand-mediated activation of Notch. Loss of C/EBPα expression is selected for within previously irradiated HSC and mHPC pools and is associated with reversal of IR-dependent precocious differentiation and restoration of self-renewal. Remarkably, restoration of mHPC self-renewal by ligand-mediated activation of Notch prevents selection for C/EBPα loss of function in previously irradiated mHPC pools. We propose that environmental insults prompt HSC to initiate a program limiting their self-renewal, leading to loss of the damaged HSC from the pool while allowing this HSC to temporarily contribute to differentiated cell pools. This “programmed mediocrity” is advantageous for the sporadic genotoxic insults animals have evolved to deal with but becomes tumor promoting when the entire HSC compartment is damaged, such as during total body irradiation, by increasing selective pressure for adaptive oncogenic mutations. Stem Cells  2015;33:1345–1358
Hematopoietic Stem/Progenitor Cells Directly Contribute to Arteriosclerotic Progression via Integrin β2
Authors: Wang Xuhong , Gao Mingming , Schouteden Sarah , Roebroek Anton , Eggermont Kristel , van Veldhoven Paul P. , Liu George , Peters Thorsten , Scharffetter-Kochanek Karin , Verfaillie Catherine M. , Feng Yingmei
Published: December 2014

Recent studies described the association between hematopoietic stem/progenitor cell (HSPC) expansion in the bone marrow (BM), leukocytosis in the peripheral blood, and accelerated atherosclerosis. We hypothesized that circulating HSPC may home to inflamed vessels, where they might contribute to inflammation and neointima formation. We demonstrated that Lin− Sca-1+ cKit+ (LSK cells) in BM and peripheral blood of LDLr−/− mice on high fat diet expressed significantly more integrin β2, which was responsible for LSK cell adhesion and migration toward ICAM-1 in vitro, and homing to injured arteries in vivo, all of which were blocked with an anti-CD18 blocking antibody. When homed LSK cells were isolated from ligated artery and injected to irradiated recipients, they resulted in BM reconstitution. Injection of CD18+/+ LSK cells to immunodeficient Balb/C Rag2− ɣC−/− recipients resulted in more severe inflammation and reinforced neointima formation in the ligated carotid artery, compared to mice injected with PBS and CD18−/− LSK cells. Hypercholesterolemia stimulated ERK phosphorylation (pERK) in LSK cells of LDLr−/− mice in vivo. Blockade of pERK reduced ARF1 expression, leading to decreased integrin β2 function on HSPC. In addition, integrin β2 function could be regulated via ERK-independent LRP1 pathway. Integrin β2 expression on HSPC is regulated by hypercholesterolemia, specifically LDL, in pERK-dependent and -independent manners, leading to increased homing and localization of HSPC to injured arteries, which is highly correlated with arteriosclerosis. Stem Cells  2015;33:1230–1240
The RUNX1 +24 Enhancer and P1 Promoter Identify a Unique Subpopulation of Hematopoietic Progenitor Cells Derived from Human Pluripotent Stem Cells
Authors: Ferrell Patrick I. , Xi Jiafei , Ma Chao , Adlakha Mitali , Kaufman Dan S.
Published: December 2014

Derivation of hematopoietic stem cells (HSCs) from human pluripotent stem cells remains a key goal for the fields of developmental biology and regenerative medicine. Here, we use a novel genetic reporter system to prospectively identify and isolate early hematopoietic cells derived from human embryonic stem cells (hESCs) and human induced pluripotent cells (iPSCs). Cloning the human RUNX1c P1 promoter and +24 enhancer to drive expression of tdTomato (tdTom) in hESCs and iPSCs, we demonstrate that tdTom expression faithfully enriches for RUNX1c-expressing hematopoietic progenitor cells. Time-lapse microscopy demonstrated the tdTom+ hematopoietic cells to emerge from adherent cells. Furthermore, inhibition of primitive hematopoiesis by blocking Activin/Nodal signaling promoted the expansion and/or survival of the tdTom+ population. Notably, RUNX1c/tdTom+ cells represent only a limited subpopulation of the CD34+CD45+ and CD34+CD43+ cells with a unique genetic signature. Using gene array analysis, we find significantly lower expression of Let-7 and mir181a microRNAs in the RUNX1c/tdTom+ cell population. These phenotypic and genetic analyses comparing the RUNX1c/tdTom+ population to CD34+CD45+ umbilical cord blood and fetal liver demonstrate several key differences that likely impact the development of HSCs capable of long-term multilineage engraftment from hESCs and iPSCs. Stem Cells  2015;33:1130–1141
Ciliary Neurotrophic Factor Promotes the Activation of Corneal Epithelial Stem/Progenitor Cells and Accelerates Corneal Epithelial Wound Healing
Authors: Zhou Qingjun , Chen Peng , Di Guohu , Zhang Yangyang , Wang Yao , Qi Xia , Duan Haoyun , Xie Lixin
Published: December 2014

Ciliary neurotrophic factor (CNTF), a well-known neuroprotective cytokine, has been found to play an important role in neurogenesis and functional regulations of neural stem cells. As one of the most innervated tissue, however, the role of CNTF in cornea epithelium remains unclear. This study was to explore the roles and mechanisms of CNTF in the activation of corneal epithelial stem/progenitor cells and wound healing of both normal and diabetic mouse corneal epithelium. In mice subjecting to mechanical removal of corneal epithelium, the corneal epithelial stem/progenitor cell activation and wound healing were promoted by exogenous CNTF application, while delayed by CNTF neutralizing antibody. In cultured corneal epithelial stem/progenitor cells, CNTF enhanced the colony-forming efficiency, stimulated the mitogenic proliferation, and upregulated the expression levels of corneal epithelial stem/progenitor cell-associated transcription factors. Furthermore, the promotion of CNTF on the corneal epithelial stem/progenitor cell activation and wound healing was mediated by the activation of STAT3. Moreover, in diabetic mice, the content of CNTF in corneal epithelium decreased significantly when compared with that of normal mice, and the supplement of CNTF promoted the diabetic corneal epithelial wound healing, accompanied with the advanced activation of corneal epithelial stem/progenitor cells and the regeneration of corneal nerve fibers. Thus, the capability of expanding corneal epithelial stem/progenitor cells and promoting corneal epithelial wound healing and nerve regeneration indicates the potential application of CNTF in ameliorating limbal stem cell deficiency and treating diabetic keratopathy. Stem Cells  2015;33:1566–1576
Inexpensive, Clean, Reliable Energy Will Require Engineered Systems
Authors: Pavlak Alex
Published: December 2014

Although small emission reductions are easy, large reductions will demand engineered systems. Classical system engineering (SE) development begins with ultimate goals such as big (>90%) reductions in greenhouse gas emissions. The first SE phase, concept development, consists of system tradeoffs to clarify feasible concepts and focus development efforts. These system studies begin with simple concept models and then build complexity in stages to elucidate principles, interfaces, and requirements. The concept definition phase is classically concluded with a critical review followed by a management decision, a value choice. Overall, classical SE starts with the ultimate goals, then works backward to allocate requirements and figure out how to get there from here. Contrast this with today's forward migration approach. Migrating forward without a clear path to an ultimate goal runs the risk of dead end development, stuck with concepts that cannot reach the ultimate goal. This paper illustrates concept development needs for both wind systems and for civilian nuclear power.
Selective element fission approach for fast FEM simulation of incremental sheet forming based on dual-mesh system
Authors: Zhang M. H. , Lu B. , Chen J. , Long H. , Ou H.
Published: December 2014

Incremental sheet forming (ISF) is a highly versatile and flexible process for producing low batches of sheet metal parts. Although finite element (FE) method is a key approach in the study of material deformation in metal forming processes, the application of FE in ISF process is still limited. This is due to the enormous simulation time required for ISF processes. Focusing on this problem, this paper presents a new selective element fission (SEF) approach for simulation of ISF process based on LS-DYNA. In the approach, the computational efficiency is improved by reducing the unnecessary calculations of elements outside the localized deformation zone in the ISF process. The introduction of a background mesh for simulation data storage and a separate simulation mesh with varied mesh density for simulation ensures both the efficiency of computation and accuracy of results. To verify the proposed SEF method, two ISF case problems including a hyperbolic cone part and a pyramid part are studied by comparing to the conventional FE approach and the H-adaptive approach in terms of the CPU time, the forming load, the final part profile, and thickness distribution. The influence of two key factors: element size ratio and toolpath segment length is also studied. The results suggested that the developed SEF approach can save the CPU time by up to 74 % with satisfactory accuracy as compared to conventional FE method, which demonstrates both the effectiveness and robustness of the developed SEF approach.