bluuebunny/crossref_metadata_2025_split huggingface dataset:
Functional Analysis of PilT from the Toxic Cyanobacterium
Microcystis aeruginosa
PCC 7806
Authors: Nakasugi Kenlee , Alexova Ralitza , Svenson Charles J. , Neilan Brett A. 
Published: December 2006

ABSTRACT

The evolution of the microcystin toxin gene cluster in phylogenetically distant cyanobacteria has been attributed to recombination, inactivation, and deletion events, although gene transfer may also be involved. Since the microcystin-producing
Microcystis aeruginosa
PCC 7806 is naturally transformable, we have initiated the characterization of its type IV pilus system, involved in DNA uptake in many bacteria, to provide a physiological focus for the influence of gene transfer in microcystin evolution. The type IV pilus genes
pilA
,
pilB
,
pilC
, and
pilT
were shown to be expressed in
M. aeruginosa
PCC 7806. The purified PilT protein yielded a maximal ATPase activity of 37.5 ± 1.8 nmol P
i
min
−1
mg protein
−1
, with a requirement for Mg
2+
. Heterologous expression indicated that it could complement the
pilT
mutant of
Pseudomonas aeruginosa
, but not that of the cyanobacterium
Synechocystis
sp. strain PCC 6803, which was unexpected. Differences in two critical residues between the
M. aeruginosa
PCC 7806 PilT (7806 PilT) and the
Synechocystis
sp. strain PCC 6803 PilT proteins affected their theoretical structural models, which may explain the nonfunctionality of 7806 PilT in its cyanobacterial counterpart. Screening of the
pilT
gene in toxic and nontoxic strains of
Microcystis
was also performed.
In Vitro Analysis of Rates and Spectra of Mutations in a Polymorphic Region of the Rv0746 PE_PGRS Gene of
Mycobacterium tuberculosis
Authors: Machowski Edith E. , Barichievy Samantha , Springer Burkhard , Durbach Steven I. , Mizrahi Valerie 
Published: December 2006

ABSTRACT

An assay modeled on a known polymorphism in the PE_PGRS9 gene of
Mycobacterium tuberculosis
was designed to assess the mutability of a sequence containing interspersed PGRS repeats. Application of the assay in
Mycobacterium smegmatis
revealed sequence plasticity: in addition to recapitulating the mutation on which it was based, other mutations likely mediated by replication slippage between PGRS repeats were detected. However, the mutation rates argued against marked hypermutability of such sequences in mycobacteria.
Physiologic Effects of Forced Down-Regulation of
dnaK
and
groEL
Expression in
Streptococcus mutans
Authors: Lemos José A. , Luzardo Yaima , Burne Robert A. 
Published: December 2006

ABSTRACT

Strains of
Streptococcus mutans
lacking DnaK or GroEL appear not to be isolable. To better distinguish the roles played by these chaperones/chaperonins in the physiology of
S. mutans
, we created a knockdown strategy to lower the levels of DnaK by over 95% in strain SM12 and the level of GroEL about 80% in strain SM13. Interestingly, GroEL levels were approximately twofold higher in SM12 than in the parent strain, but the levels of DnaK were not altered in the GroEL knockdown strain. Both SM12 and SM13 grew slower than the parent strain, had a strong tendency to aggregate in broth culture, and showed major changes in their proteomes. Compared with the wild-type strain, SM12 and SM13 had impaired biofilm-forming capacities when grown in the presence of glucose. The SM12 strain was impaired in its capacity to grow at 44°C or at pH 5.0 and was more susceptible to H
2
O
2
, whereas SM13 behaved like the wild-type strain under these conditions. Phenotypical reversions were noted for both mutants when cells were grown in continuous culture at a low pH, suggesting the occurrence of compensatory mutations. These results demonstrate that DnaK and GroEL differentially affect the expression of key virulence traits, including biofilm formation and acid tolerance, and support that these chaperones have evolved to accommodate unique roles in the context of this organism and its niche.
SequentialWT1andCTNNB1mutations and alterations of β-catenin localisation in intralobar nephrogenic rests and associated Wilms tumours: two case studies
Authors: Fukuzawa Ryuji , Heathcott Rosemary W , More Helen E , Reeve Anthony E 
Published: December 2006

Background:Intralobar nephrogenic rests (ILNRs) are precursor lesions for Wilms tumours and are associated withWT1gene mutations. ILNR-associated Wilms tumours have a co-clustering ofWT1and β-catenin (CTNNB1) mutations and unique histological features characterised by a stromal-predominant histology.Aim:To determine the order in whichWT1andCTNNB1mutations occur to understand the ILNR–Wilms tumour sequence.Methods:Of nine Wilms tumours withWT1andCTNNB1mutations, three ILNRs lesions in two Wilms tumours were available for analysis ofWT1andCTNNB1mutations using microdissection. Immunohistochemistry was also performed to investigate how the mutations in β-catenin alter the localisation in Wilms tumour development.Results:WT1mutations were present in the ILNRs, howeverCTNNB1mutations were absent. Immunohistochemistry for WT1 confirmed inactivation of WT1 in both ILNRs and Wilms tumours. Both the ILNRs and the associated Wilms tumours had similar immunostaining patterns for β-catenin in the blastemal and epithelial components. Although rhabdomyoblasts were not included in ILNRs, the associated Wilms tumours showed rhabdomyogenic differentiation with a positive β-catenin nuclear staining.Conclusions:The results suggest thatCTNNB1mutation is a later event in Wilms tumourigenesis.CTNNB1mutations might be associated with rhabdomyogenesis.
Recurrence in Levinas Recurrence in Levinas
Authors: Smith Michael 
Published: December 2006

AbstractThe article differentiates between the manifestation of recurrence qua consciousness and an underlying recurrence elaborated by Levinas in subjectivity beyond being. The movement of recurrence is traced in its relation to creation. Ethics is the language in which the selfless can be expressed, where value obtains in lieu of being. The philosophical problem to which recurrence is a response is posited as ipseity versus identiy. The self imposed obstacles to extracting a moral doctrine from the levinasian corpus are discussed, followed by suggestions on the difference a levinasian view might make in our understanding and undertaking of every day life.
Juan Luis Vives' Conception of Freedom of the Will and Its Scholastic Background
Authors: Casini Lorenzo 
Published: December 2006

AbstractThe aim of the present paper is to approach Juan Luis Vives' conception of freedom of the will in light of scholastic discussions on will and free choice, and point to some interesting similarities with the analysis of free choice contained in Jean Buridan's Quaestiones super decem libros Ethicorum Aristotelis ad Nicomachum.
Mnemonic modes in Emily Nasrallah's A House not her own (Bayt Laysa Lahā)
Authors: Suyoufie Fadia 
Published: December 2006

AbstractThis study traces the various modes in which memory is represented in this collection of short stories by the Lebanese writer, Emily Nasrallah. By placing the processes of remembering in these stories against the background of violence and "dismemberment" which prevailed in Beirut during the civil war, the study reveals the sense of dislocation and estrangement from "home" which is at the heart of Nasrallah's work. It also dismantles the strategies and techniques that Nasrallah utilizes to give a voice to the "voiceless" victims and survivors of this war.Whether partly recuperative or absolutely tyrannical in its effects, memory functions as an essential medium for the reclamation of the past and the protestation against the dehumanizing effects of war. For the woman writer herself, writing about or remembering the war grants her the chance to sublimate suffering into artistic creativity which finds expression in the act of storytelling itself.
A Qasīdah by Ibn Muqbil the deeper reaches of lyricism and experience in a Mukhadram poem: An essay in three steps
Authors: Stetkevych Jaroslav 
Published: December 2006

AbstractIn his Tabaqāt Fuhūl al-Shu'arā', the 3rd/9th century literary critic al-Jumahī cites two lines from a poem by the Mukhadram (bridging the Jāhiliyyah and Islam) poet, Ibn Muqbil, which, he claims, express through the traditional image of weeping at the ruined abodes the poet's nostalgia for the pre-Islamic age. The present essay expands upon al-Jumahī's observation by placing the two lines he cites within the context of the full original qasīdah of fifty lines. In doing so, it demonstrates that the entire qasīdah in its themes and motifs is to be interpreted as an expression of nostalgia for the lost age of the Jāhiliyyah. Above all, the structure of the poem constitutes a dramatic inversion of the traditional qasīdah structure. The effect of this inversion is to replace the normal temporal and affective trajectory of the poem from past to present, with a reversed trajectory from present to past. Whereas al-Jumahī expresses puzzlement over how a Muslim could feel longing for the pagan past, this essay turns to the full text of the poem to uncover the nostalgic counter-current that accompanied the massive cultural transition from the Jāhiliyyah to Islam. It shows how Ibn Muqbil manipulates the traditional themes, motifs, and structures of the pre-Islamic qasīdah to express his political resentment at the destruction of his way of life.
How Bargaining Alters Outcomes: Bilateral Trade Negotiations and Bargaining Strategies
Authors: Elms Deborah 
Published: December 2006

AbstractThis article considers bargaining strategies used by government negotiators in the context of bilateral trade disputes. I argue that trade officials reach the most durable agreements by using an integrative, or value-creating, strategy and avoiding the use of threats. By contrast, a highly distributive, value-claiming strategy coupled with loud public threats is unlikely to result in a durable agreement and frequently leads to deadlocked negotiations. The irony, however, is that American officials use the latter approach more frequently than the former in bilateral trade disputes. These strategies are usually chosen unconsciously in response to perceptions of losses that drive negotiators to select risky approaches to resolve disputes.By examining bargaining strategies in the U.S. disputes with Japan and South Korea over automobiles and auto parts in the 1990s, this article identifies shifts in negotiation strategies. These shifts in approach closely track the outcomes in these two deeply contentious disputes. After protracted and contentious negotiations with Japan, the final outcome represented a failure to achieve the Americans' most important goals. A less confrontational strategy with South Korea ultimately resulted in greater market opening.
Regulation of Genetic and Other Health Information in a Comparative Perspective
Authors: Gerards Janneke , Janssen Heleen 
Published: December 2006

AbstractIn the present article, the authors provide a general overview of the academic and legal debate on the regulation of access to and use of genetic information by non-medical actors. Their aim is to give some insight in the academic views on the need to introduce specific genetics legislation and on the balance that might be struck between the various interests concerned. Furthermore, by analyzing relevant legislation and policy measures in the US and in Europe, they identify the issues that are deemed relevant in considering and, eventually, introducing regulative measures with respect to genetic information.
Perceptions and correlates of peer‐victimization and bullying
Authors: Hunter Simon C. , Boyle James M. E. , Warden David. 
Published: December 2006

Background. The experiences of peer‐victimization and bullying are often treated empirically as though they are conceptually indistinct. Both involve repeated aggression, but definitions of bullying additionally emphasize the importance of aggressor intent and imbalance of power between the aggressor and the victim (Olweus, 1978; Whitney & Smith, 1993).Aims. The present study aimed to examine the extent to which peer‐victimization and bullying are empirically similar.Sample. The sample comprised 1,429 pupils (50.2% male) aged between 8 and 13 years attending mainstream Scottish schools.Method. Self‐report questionnaire assessing peer‐victimization and bullying, coping strategy use (WCCL: Hunter, 2000), situational appraisal and depressive symptomatology (Birleson, 1981).Results. Almost one‐third (30.7%) of pupils reported experiencing peer‐victimization, and of these 38.1% (11.7% of whole sample) were categorized as victims of bullying. Victims of bullying perceived higher levels of threat and lower levels of perceived control. They also reported using more Wishful Thinking and Social Support coping strategies, but did not differ on Problem Focused coping. Bullied pupils also reported higher levels of depressive symptomatology.Conclusions. Peer‐victimization and bullying appear to be qualitatively different experiences for children and adolescents, with bullying being the more serious phenomenon.
Nuchal cystic hygroma in five fetuses from 1819 to 1826 in the Meckel‐anatomical collections at the University of Halle, Germany
Authors: Göbbel Luminita , Schultka Rüdiger , Klunker Rudyard , Stock Karsten , Helm Jürgen , Olsson Lennart , Opitz John M. , Gerlach Antje , Tönnies Holger 
Published: December 2006

AbstractThe Anatomical collection of the Department of Anatomy and Cell Biology, Medical School of the University of Halle, Germany, comprises more than 8,000 specimens. Around 600 of them show congenital anomalies. The collection of abnormal human and animal fetuses began as the private collection of Johann Friedrich Meckel the Elder (1724–1774), his son Philipp Friedrich Theodor Meckel (1755–1803) and his grandson Johann Friedrich Meckel the Younger (1781–1833). Meckel the Younger founded the systematic science of developmental pathology. Radiographical techniques, computer tomographic (CT) methods, magnetic resonance imaging (MRI), and comparative genomic hybridization (CGH) were used to diagnose abnormal human fetuses in the Meckel‐anatomical collections. Cystic hygroma colli was found in five of the human fetuses originally described by JF Meckel the Younger in 1826 and one of his students in 1819 [Hencke, 1819]. CGH analyses were used to test whether the observed cystic hygroma colli could be caused by chromosomal aneuploidies. CGH‐ratio profiles of all chromosomes were apparently normal. PCR‐based sex determination tests on ancient DNA were used to determine the fetal gonosomal constitution. It is likely that the Meckel specimens are among the oldest fetuses in which Ullrich–Turner “phenotype” has been diagnosed. © 2006 Wiley‐Liss, Inc.
Autosomal‐recessive syndrome with alopecia, hypogonadism, progressive extra‐pyramidal disorder, white matter disease, sensory neural deafness, diabetes mellitus, and low IGF1
Authors: Al‐Semari Abdulaziz , Bohlega Saeed 
Published: December 2006

AbstractWe explored the manifestations of an autosomal‐recessive multisystemic disorder in several Saudi families. Recognized causes of progressive extra‐pyramidal disorder and white matter disease were excluded and the neurological, imaging, endocrine, and skin manifestations of this syndrome described. The onset of these symptoms in these patients began in early adolescence and progressed more rapidly in males. All affected patients had total or partial alopecia, clinical and chemical evidence of hypogonadism (low levels of estradiol and testosterone); females had clear evidence of hypogonadism (streak or absent ovaries), and some patients had diabetes mellitus and/or sensorineural deafness. The constant biochemical abnormality was the low IGF‐1. The neurological manifestations included moderate to severe intellectual decline and abnormality of muscle tone and posture with choreo‐athetoid and dystonic movements resulting in gait difficulty, dysarthria, difficulty swallowing, and scoliosis. The MRI of brain demonstrated white matter involving cerebellum, brain stem, and cerebral structures, as well as abnormal decreased signal intensity in the basal ganglia with involvement of the substantia nigra. We conclude that the association of hypogonadism, alopecia, and persistent low IGF‐1 is a significant autosomal recessive syndrome; it is prevalent in Saudi Arabia. We also demonstrate that the progressive extra‐pyramidal disorder, white matter disease, and abnormal signals of the basal ganglia are common features of this syndrome. Sensorineural deafness and diabetes mellitus were recognized features. © 2006 Wiley‐Liss, Inc.
Linkage of schizophrenia with chromosome 1q32 in Korean multiplex families'
Authors: Jang Yong Lee , Kim Jong Won , Lee Yu‐Sang , Park Dong Yeon , Cho Eun‐Young , Jeun Hyun Ok , Lee Dongsoo , Hong Kyung Sue 
Published: December 2006

AbstractChromosome 1q contains a few loci for which modest evidence of linkage with schizophrenia has been reported in several independent studies. However, markers showing the peak linkage signal are dispersed over a large chromosomal region. In addition, inconsistent findings have been generated from different populations or different subgroups of the same populations. The purpose of the current study is to determine whether those loci are linked to schizophrenia in the Korean population. We investigated 46 Korean multiplex schizophrenia families, initially using 11 microsatellite markers spanning around 91 cM region of 1p22∼42. In a non‐parametric linkage analysis, D1S249 located on 1q32.1 showed statistical evidence suggestive of linkage. At the second stage analysis for narrowing down the region, four additional nearby markers were genotyped. In the single point analysis, we found another suggestive linkage signal at D1S2891. The highest NPL score of 2.67 (P = 0.0039) was obtained in the multi‐point analysis. This study provides supportive evidence for linkage of chromosome 1q32 with schizophrenia. © 2006 Wiley‐Liss, Inc.
Association analysis of the protein phosphatase 1 regulatory subunit 1B (PPP1R1B) gene with nicotine dependence in European‐ and African‐American smokers
Authors: Beuten Joke , Ma Jennie Z. , Lou Xiang‐Yang , Payne Thomas J. , Li Ming D. 
Published: December 2006

AbstractThe protein phosphatase 1 regulatory subunit 1B gene (PPP1R1B; also known as dopamine and cAMP‐regulated phosphoprotein; DARPP32) is a target for the actions of dopamine. Because the mesolimbic dopaminergic system is implicated in the reinforcing effects of many drugs, including nicotine,PPP1R1Bis considered a plausible candidate for involvement in the development of vulnerability to nicotine dependence (ND). Further, this gene is located within a region on chromosome 17 that demonstrated “suggestive linkage” to ND in our previous genome‐wide scan. In the present study, we analyzed six single nucleotide polymorphisms (SNPs) withinPPP1R1Bfor association with three ND measures: smoking quantity (SQ), the heaviness of smoking index (HSI), and the Fagerström Test for ND (FTND) score. Our sample consisted of 602 nuclear families of African‐American (AA) or European‐American (EA) origin. No significant associations were found for single SNPs after correction for multiple testing. However, haplotype analysis indicated that in the EA sample, the C‐T‐G‐C haplotype formed by rs2271309‐rs907094‐rs3764352‐rs3817160 with a frequency of 32.0% was significantly associated with SQ (Z = 2.50;P = 0.01), even after Bonferroni correction. No significant associations with haplotypes were found in the AA sample. In summary, our findings provide the first evidence for the potential involvement ofPPP1R1Bin the etiology of ND and further investigation is thus warranted. © 2006 Wiley‐Liss, Inc.
Sequence variants within exon 1 of MECP2 occur in females with mental retardation
Authors: Harvey Chris G. , Menon Sailesh D. , Stachowiak Beata , Noor Abdul , Proctor Adam , Mensah Albert K. , Mnatzakanian Gevork N. , Alfred Simon E. , Guo Ray , Scherer Stephen W. , Kennedy James L. , Roberts Wendy , Srivistava Anand K. , Minassian Berge A. , Vincent John B. 
Published: December 2006

AbstractA new splice variant of the Rett syndrome gene, MECP2, was recently identified, that includes coding sequence from exon 1, and is the predominant transcript in the central nervous system. This sequence encodes polyalanine and polyglycine stretches within the N‐terminal portion of MeCP2, and may confer novel functional properties to the protein. We screened autism, mental retardation (MR), and control populations for sequence variation within this region, and identified variation in ∼1% of MR cases screened (N = 1,410). No variants were identified in the autism sample (N = 401). Most of these variants occur within a trinucleotide repeat region and result in change in number of alanine or glycine residues within the repeat stretches. We suggest some of these variants may be a relatively frequent cause of non‐specific MR or developmental delay. © 2006 Wiley‐Liss, Inc.
Oligodendroglial transcription factor (OLIG1 and OLIG2) mutations are not associated with Pelizaeus–Merzbacher‐like leukodystrophy
Authors: Ruf Nico , Martelli Mara , Weschke Bernhard , Uhlenberg Birgit 
Published: December 2006

AbstractThe human phenotype with primarily impaired myelination is represented by hypomyelinating leukodystrophies. The most frequent form is Pelizaeus–Merzbacher disease, which is due to alterations in the PLP1 gene encoding the major myelin protein. Another form, Pelizaeus–Merzbacher‐like disease, is partly associated with mutations in the GJA12 gene encoding gap junction protein alpha 12, but seems to be heterogeneous. Olig1 and Olig2 are transcription factors in oligodendrocyte development. We postulated that disturbed oligodendroglial maturation could be associated with primary hypomyelination in humans and analyzed the coding sequence of OLIG1 and OLIG2 in 13 patients from 12 unrelated families which were thoroughly characterized with regard to phenotype and magnetic resonance imaging results. From our findings we conclude that mutations in OLIG1 and OLIG2 are not likely to be associated with this subgroup of hypomyelinating disorders. © 2006 Wiley‐Liss, Inc.
Cyclooxygenase‐2 polymorphisms in Parkinson's disease
Authors: Håkansson Anna , Bergman Olle , Chrapkowska Cecilia , Westberg Lars , Belin Andrea Carmine , Sydow Olof , Johnels Bo , Olson Lars , Holmberg Björn , Nissbrandt Hans 
Published: December 2006

AbstractAccumulating evidence indicate that cyclooxygenase‐2 (COX‐2) is of pathophysiological importance for the neurodegeneration in Parkinson's disease (PD). For example, in a large epidemiological study, use of NSAIDs was associated with a lower risk of PD. Genetic variants of the COX‐2 gene might therefore influence the risk of developing the disease. The genotype distribution of four common single nucleotide polymorphisms (SNPs) in the COX‐2 gene (rs689466:A496G, rs20417:G926C, rs5277:G3050C, rs5275:C8473T) was analyzed in PD patients and control subjects in a Swedish population. No differences could be seen between the PD‐patient and controls regarding the A496G, G926C, and G3050C SNPs, but the allele frequency of the C8473T SNP was found to differ when male patients were compared to controls (P = 0.007). In females no difference could be seen between PD‐patients and controls. In conclusion, the results suggest a possible influence of the COX‐2 C8473T SNP in PD, although it only seems to be of importance in men. © 2006 Wiley‐Liss, Inc.