bluuebunny/crossref_metadata_2025_split huggingface dataset:
It takes two DNA translocases to untangle chromosomes from the division septum
Authors: Wu Ling Juan 
Published: September 2009

SummaryThe DNA translocase function of Bacillus subtilis SpoIIIE is essential for spore development and is important during vegetative growth for moving trapped chromosomal DNA away from division septa. Two papers in this issue of Molecular Microbiology, from the teams of Peter Graumann and William Burkholder, have characterized a second SpoIIIE/FtsK‐like protein in B. subtilis, SftA. This protein lacks any recognizable transmembrane domain possessed by the other characterized members of the family, yet the protein is shown to be associated with the division septum and, like SpoIIIE, is required for clearing DNA from the septum. However, SftA and SpoIIIE act at different stages of septation and together they ensure maximum fidelity in chromosome segregation.
The Bacillus subtilis SftA (YtpS) and SpoIIIE DNA translocases play distinct roles in growing cells to ensure faithful chromosome partitioning
Authors: Biller Steven J. , Burkholder William F. 
Published: September 2009

SummaryIn several bacterial species, the faithful completion of chromosome partitioning is known to be promoted by a conserved family of DNA translocases that includes Escherichia coli FtsK and Bacillus subtilis SpoIIIE. FtsK localizes at nascent division sites during every cell cycle and stimulates chromosome decatenation and the resolution of chromosome dimers formed by recA‐dependent homologous recombination. In contrast, SpoIIIE localizes at sites where cells have divided and trapped chromosomal DNA in the membrane, which happens during spore development and under some conditions when DNA replication is perturbed. SpoIIIE completes chromosome segregation post‐septationally by translocating trapped DNA across the membrane. Unlike E. coli, B. subtilis contains a second uncharacterized FtsK/SpoIIIE‐like protein, SftA (formerly YtpS). We report that SftA plays a role similar to FtsK during each cell cycle but cannot substitute for SpoIIIE in rescuing trapped chromosomes. SftA colocalizes with FtsZ at nascent division sites but not with SpoIIIE at sites of chromosome trapping. SftA mutants divide over unsegregated chromosomes more frequently than wild‐type unless recA is inactivated, suggesting that SftA, like FtsK, stimulates chromosome dimer resolution. Having two FtsK/SpoIIIE paralogues is not conserved among endospore‐forming bacteria, but is highly conserved within several groups of soil‐ and plant‐associated bacteria.
Two NDR kinase–MOB complexes function as distinct modules during septum formation and tip extension in Neurospora crassa
Authors: Maerz Sabine , Dettmann Anne , Ziv Carmit , Liu Yi , Valerius Oliver , Yarden Oded , Seiler Stephan 
Published: September 2009

SummaryNDR kinases are important for growth and differentiation and require interaction with MOB proteins for activity and function. We characterized the NDR kinases and MOB activators in Neurospora crassa and identified two NDR kinases (COT1 and DBF2) and four MOB proteins (MOB1, MOB2A, MOB2B and MOB3/phocein) that form two functional NDR–MOB protein complexes. The MOB1–DBF2 complex is not only essential for septum formation in vegetative cells and during conidiation, but also functions during sexual fruiting body development and ascosporogenesis. The two MOB2‐type proteins interact with both COT1 isoforms and control polar tip extension and branching by regulating COT1 activity. The conserved region directly preceding the kinase domain of COT1 is sufficient for the formation of COT1–MOB2 heterodimers, but also for kinase homodimerization. An additional N‐terminal extension that is poorly conserved, but present in most fungal NDR kinases, is required for further stabilization of both types of interactions and for stimulating COT1 activity. COT1 lacking this region is degraded in a mob‐2 background. We propose a specific role of MOB3/phocein during vegetative cell fusion, fruiting body development and ascosporogenesis that is unrelated to the three other MOB proteins and NDR kinase signalling.
Ras1 and Ras2 play antagonistic roles in regulating cellular cAMP level, stationary‐phase entry and stress response in Candida albicans
Authors: Zhu Yong , Fang Hao‐Ming , Wang Yan‐Ming , Zeng Gui‐Sheng , Zheng Xin‐De , Wang Yue 
Published: September 2009

SummaryThe GTPase Ras1 activates the yeast‐to‐hypha transition in Candida albicans by activating cAMP synthesis. Here, we have characterized Ras2. Ras2 belongs to a group of atypical Ras proteins in some fungal species that share poor identity with other Ras GTPases with many variations in conserved motifs thought to be crucial for Ras‐associated activities. We find that recombinant Ras2 is enzymatically as active as Ras1. However, only RAS1 can rescue the lethality of the Saccharomyces cerevisiae ras1 ras2 mutant, suggesting functional divergence of the two genes. ras2Δ is normal in hyphal growth, but deleting RAS2 in the ras1Δ background greatly aggravates the hyphal defect, indicating that Ras2 also has a role in hyphal development. Strikingly, while RAS1 deletion causes a ∼20‐fold decrease in cellular cAMP, further deletion of RAS2 restores it to ∼30% of the wild‐type level. Consistently, while the ras1Δ mutant enters the stationary phase prematurely, the double mutant does so normally. Moreover, ras1Δ cells exhibit increased resistance to H2O2 and higher sensitivity to the heavy metal Co2+, whereas ras2Δ cells show the opposite phenotypes. Together, our data reveal a novel regulatory mechanism by which two antagonizing Ras GTPases balance each other in regulating multiple cellular processes in C. albicans.
In vitro detection and characterization of drug hypersensitivity using flow cytometry
Authors: Martin M. , Wurpts G. , Ott H. , Baron J. M. , Erdmann S. , Merk H. F. , Sachs B. 
Published: October 2009

AbstractBackground:  The lymphocyte transformation test (LTT) is the only in vitro test for detecting drug sensitization at the cellular level irrespective of the reaction’s phenotype. However, the LTT includes working with radioactive substances and is considered impracticable for routine laboratory investigation.Objective:  The aim of this study was to assess drug‐specific cytokine production by means of flow cytometry as an alternative nonradioactive approach which may be more appropriate for routine testing and may provide in addition more information about the pathophysiology of the reaction than proliferation‐based assays, like the LTT.Method:  Peripheral blood mononuclear cells of 19 patients were incubated with culprit drugs (n = 28) or irrelevant antigens (n = 10). Ten healthy persons served as controls for all different drugs (n = 15). Intracellular interleukin (IL)‐5, interferon (IFN)‐γ and IL‐10 production was investigated using flow cytometry. Accuracy of the flow cytometry test system was confirmed using different statistical tests, i.e. receiver operating characteristic curve and Mann–Whitney rank test. In addition, drug‐specific secretion of IL‐5, IL‐2 and IFN‐γ were analysed using enzyme‐linked immunosorbent assay (ELISA).Results:  Drug‐specific cytokine production could be demonstrated in 75% of the patients using flow cytometry and in 79% using ELISA respectively. Combining ELISA and flow cytometry increased the sensitivity to 100%. Analysis of involved T‐cell subsets [e.g. CD4+ or CD8+; T helper (TH) 1 or TH 2] allowed characterization of the in vitro lymphocyte reactivity pattern.Conclusions:  Analysis of drug‐specific cytokine production by means of flow cytometry proved a useful and reliable approach for the in vitro detection and characterization of drug hypersensitivities.
Functional analysis of CYP1B1 mutations and association of heterozygous hypomorphic alleles with primary open‐angle glaucoma
Authors: López‐Garrido M‐P , Blanco‐Marchite C , Sánchez‐Sánchez F , López‐Sánchez E , Chaqués‐Alepuz V , Campos‐Mollo E , Salinas‐Sánchez AS , Escribano J 
Published: September 2009

López‐Garrido M‐P, Blanco‐Marchite C, Sánchez‐Sánchez F, López‐Sánchez E, Chaqués‐Alepuz V, Campos‐Mollo E, Salinas‐Sánchez AS, Escribano J. Functional analysis of CYP1B1 mutations and association of heterozygous hypomorphic alleles with primary open‐angle glaucoma.Glaucoma is an inherited complex and heterogeneous disease, and one of the most prevalent causes of definitive blindness in the world. Recent reports have indicated that heterozygous mutations of the CYTOCHOROME P4501B1 (CYP1B1) gene are present in 4–10% of patients with primary open‐angle glaucoma (POAG). To further evaluate the role of CYP1B1 mutations in POAG we extended our previous association study and carried out a functional analysis of the mutations identified by polymerase chain reaction (PCR) DNA sequencing of the three exons of the gene in a total of 245 unrelated Spanish patients and 326 control subjects. Eight of nine different mutations identified in these patients were cloned and functionally assessed by measuring ethoxyresorufin O‐deethylation activity and CYP1B1 stability in transiently transfected HEK‐293T cells. All these mutants showed reduced catalytic activity, ranging from 20% to 60% of wild‐type and/or decreased protein stability and, therefore, they were classified as hypomorphic alleles. No null alleles were identified in these patients. We found heterozygous hypomorphic CYP1B1 mutations in 17 (6.7%) patients and in seven controls (2.1%) showing that these mutations are associated with an increased risk of POAG (p = 0.005; odds ratio = 3.2; 95% confidence interval = 1.30–9.19). Our data suggest that hypomorphic CYP1B1 mutations are, to date, the main known genetic risk factor in POAG.
Allometry and performance: the evolution of skull form and function in felids
Authors: SLATER G. J. , VAN VALKENBURGH B. 
Published: September 2009

AbstractAllometric patterns of skull‐shape variation can have significant impacts on cranial mechanics and feeding performance, but have received little attention in previous studies. Here, we examine the impacts of allometric skull‐shape variation on feeding capabilities in the cat family (Felidae) with linear morphometrics and finite element analysis. Our results reveal that relative bite force diminishes slightly with increasing skull size, and that the skulls of the smallest species undergo the least strain during biting. However, larger felids are able to produce greater gapes for a given angle of jaw opening, and they have overall stronger skulls. The two large felids in this study achieved increased cranial strength by increasing skull bone volume relative to surface area. Allometry of skull geometry in large felids reflects a trade‐off between the need to increase gape to access larger prey while maintaining the ability to resist unpredictable loading when taking large, struggling prey.
Spatiotemporal frequency and speed tuning in the owl visual wulst
Authors: Pinto Lucas , Baron Jerome 
Published: September 2009

AbstractThe avian visual wulst is hodologically equivalent to the mammalian primary visual cortex (V1). In contrast to most birds, owls have a massive visual wulst, which shares striking functional similarities with V1. To provide a better understanding of how motion is processed within this area, we used sinusoidal gratings to characterize the spatiotemporal frequency and speed tuning profiles of 131 neurones recorded from awake burrowing owls. Cells were found to be clearly tuned to both spatial and temporal frequencies, and in a way that is similar to what has been reported in the striate cortex of primates and carnivores. Our results also suggest the presence of spatial frequency tuning domains in the wulst. Speed tuning was assessed by several methods devised to measure the degree of dependence between spatial and temporal frequency tuning. Although many neurones were found to be independently tuned, a significant proportion of cells showed at least some degree of dependence, compatible with the idea that some kind of initial transformation towards an explicit representation of speed is being carried out by the owl wulst. Interestingly, under certain constraints, a higher incidence of spatial frequency‐invariant speed tuned profiles was obtained by combining our experimentally measured responses using a recent cortical model of speed tuning. Overall, our findings reinforce the notion that, like V1, the owl wulst is an important initial stage for motion processing, a function that is usually attributed to areas of the tectofugal pathway in lateral‐eyed birds.
Lateral habenula projections to dopamine and GABA neurons in the rat ventral tegmental area
Authors: Omelchenko Natalia , Bell Roland , Sesack Susan R. 
Published: September 2009

AbstractVentral tegmental area (VTA) dopamine (DA) neurons and their forebrain projections are critically involved in reward processing and cognitive functions. Descending projections from the lateral habenula (LHb) play a central role in inhibiting DA cell activity in response to the absence of expected rewards. As LHb efferents are reportedly glutamatergic, their ability to inhibit DA cells would theoretically require a disynaptic connection involving VTA GABA neurons and their local collateral inputs to DA cells. We therefore used anterograde tract‐tracing from the LHb to investigate the relative selectivity of LHb synapses onto GABA versus DA VTA neurons. LHb axons were visualized using immunoperoxidase, and DA and GABA cells were marked by immunogold‐silver labeling for tyrosine hydroxylase (TH) or GABA, respectively. By ultrastructural analysis, 16% of LHb axons were observed to form synaptic contacts in the VTA, and most of these were of an intermediate morphological type that did not exhibit definitive asymmetric or symmetric character. LHb axons synaptically targeted TH‐ and GABA‐labeled dendrites to a comparable extent (45 and 52% observed incidence, respectively). Pre‐embedding immunogold labeling for the vesicular glutamate transporter type 2 and post‐embedding immunogold staining for GABA confirmed that approximately 85% of LHb terminals were glutamatergic and not GABAergic. These results suggest that the robust inhibition of DA cells evoked by the LHb is unlikely to arise from a selective innervation of VTA GABA neurons. Moreover, the LHb may mediate a direct excitation of DA cells that is over‐ridden by indirect inhibition originating from an extrinsic source.
The turnover of medium‐chain‐length polyhydroxyalkanoates in Pseudomonas putida KT2442 and the fundamental role of PhaZ depolymerase for the metabolic balance
Authors: De Eugenio Laura Isabel , Escapa Isabel F. , Morales Valle , Dinjaski Nina , Galán Beatriz , García José Luis , Prieto María A. 
Published: September 2009

SummaryPolyhydroxyalkanoates (PHAs) are biodegradable polymers produced by a wide range of bacteria, including Pseudomonads. These polymers are accumulated in the cytoplasm as carbon and energy storage materials when culture conditions are unbalanced and hence, they have been classically considered to act as sinks for carbon and reducing equivalents when nutrients are limited. Bacteria facing carbon excess and nutrient limitation store the extra carbon as PHAs through the PHA polymerase (PhaC). Thereafter, under starvation conditions, PHA depolymerase (PhaZ) degrades PHA and releases R‐hydroxyalkanoic acids, which can be used as carbon and energy sources. To study the influence of a deficient PHA metabolism in the growth of Pseudomonas putida KT2442 we have constructed two mutant strains defective in PHA polymerase (phaC1)‐ and PHA depolymerase (phaZ)‐coding genes respectively. By using these mutants we have demonstrated that PHAs play a fundamental role in balancing the stored carbon/biomass/number of cells as function of carbon availability, suggesting that PHA metabolism allows P. putida to adapt the carbon flux of hydroxyacyl‐CoAs to cellular demand. Furthermore, we have established that the coordination of PHA synthesis and mobilization pathways configures a functional PHA turnover cycle in P. putida KT2442. Finally, a new strain able to secrete enantiomerically pure R‐hydroxyalkanoic acids to the culture medium during cell growth has been engineering by redirecting the PHA cycle to biopolymer hydrolysis.
Deep sequencing reveals exceptional diversity and modes of transmission for bacterial sponge symbionts
Authors: Webster Nicole S. , Taylor Michael W. , Behnam Faris , Lücker Sebastian , Rattei Thomas , Whalan Stephen , Horn Matthias , Wagner Michael 
Published: September 2009

SummaryMarine sponges contain complex bacterial communities of considerable ecological and biotechnological importance, with many of these organisms postulated to be specific to sponge hosts. Testing this hypothesis in light of the recent discovery of the rare microbial biosphere, we investigated three Australian sponges by massively parallel 16S rRNA gene tag pyrosequencing. Here we show bacterial diversity that is unparalleled in an invertebrate host, with more than 250 000 sponge‐derived sequence tags being assigned to 23 bacterial phyla and revealing up to 2996 operational taxonomic units (95% sequence similarity) per sponge species. Of the 33 previously described ‘sponge‐specific’ clusters that were detected in this study, 48% were found exclusively in adults and larvae – implying vertical transmission of these groups. The remaining taxa, including ‘Poribacteria’, were also found at very low abundance among the 135 000 tags retrieved from surrounding seawater. Thus, members of the rare seawater biosphere may serve as seed organisms for widely occurring symbiont populations in sponges and their host association might have evolved much more recently than previously thought.
Narrow‐band imaging cystoscopy to evaluate the response to bacille Calmette‐Guérin therapy: preliminary results
Authors: Herr Harry W. 
Published: September 2009

Study Type – Diagnostic (exploratory cohort) Level of Evidence 2bOBJECTIVETo evaluate whether narrow‐band imaging cystoscopy (NBIC) can identify bladder tumour suspected on follow‐up white‐light cystoscopy (WLC) after intravesical bacille Calmette‐Guérin (BCG) therapy, as BCG causes an intense reaction in the bladder, appearing as red lesions on WLC, which might be residual tumour or BCG‐induced inflammation.PATIENTS AND METHODSSixty‐one patients with high‐risk non‐muscle‐invasive bladder tumours were evaluated 3 months after starting induction BCG therapy. All patients had abnormal erythematous lesions on WLC, suspected to be residual carcinoma in situ. After WLC, they were evaluated by NBIC, urine cytology and biopsy, followed by transurethral resection of all visible lesions.RESULTSOf the 61 patients, 22 (36%) had residual tumour. NBIC correctly identified tumour in 21 patients, but another 10 had unnecessary biopsy (NBIC positive, negative biopsy). Only one of 30 patients who had negative NBIC findings had tumour. NBIC outperformed urine cytology in detecting residual tumour after BCG therapy.CONCLUSIONNBIC appears to better identify patients who have suspected residual tumour on follow‐up WLC at 3 months after BCG therapy.
Transabdominal ultrasonography of detrusor wall thickness in women with overactive bladder
Authors: Chung Shiu‐Dong , Chiu Bin , Kuo Hann‐Chorng , Chuang Yao‐Chi , Wang Chung‐Cheng , Guan Zhonghong , Chancellor Michael B. 
Published: September 2009

Study Type – Diagnostic (case series) Level of Evidence 4OBJECTIVETo determine the clinical usefulness of measuring detrusor wall thickness (DWT) as a noninvasive test in women with overactive bladder (OAB).PATIENTS, SUBJECTS AND METHODSWe prospectively enrolled 122 women with dry OAB, wet OAB, and women with no OAB symptoms (control group). A 3‐day voiding diary was used to differentiate between wet and dry OAB. Transabdominal ultrasonography (TAUS) measurements of DWT were taken at bladder volumes of 250–300 mL and the maximal bladder capacity by both catheter‐ and natural‐filling. Video‐urodynamic studies (VUDS) were used to classify bladder dysfunction in 88 of the women.RESULTSThe mean (range) age of the women was 58 (20–94) years. There were 39 ‘normal’ controls, 44 women had dry OAB, and 39 had wet OAB. Of the 88 women who had VUDS, 28 had a ‘normal’ test, 30 had increased bladder sensation (IBS), and 30 had detrusor overactivity (DO). The mean DWT at 250–300 mL among three symptomatic subgroups or urodynamic subgroups showed no significant difference by either catheter‐ or natural‐filling methods. The women with wet OAB had significantly greater DWTs than the controls at maximal bladder volume. The maximal bladder capacity was significantly greater in ‘normal’ women than in those with OAB. If we corrected maximal bladder volume to 250 mL, DWT at corrected 250 mL showed no significant difference among three symptomatic subgroups.CONCLUSIONSDWT measured by TAUS in women with OAB and without OAB was not different and did not differ with urodynamic status. Thus, TAUS measurement of DWT is not recommended as a useful diagnostic test for DO in women with OAB.
Brain activation during upright and inverted encoding of own‐ and other‐age faces: ERP evidence for an own‐age bias
Authors: Melinder Annika , Gredebäck Gustaf , Westerlund Alissa , Nelson Charles A. 
Published: September 2009

AbstractWe investigated the neural processing underlying own‐age versus other‐age faces among 5‐year‐old children and adults, as well as the effect of orientation on face processing. Upright and inverted faces of 5‐year‐old children, adults, and elderly adults (> 75 years of age) were presented to participants while ERPs and eye tracking patterns were recorded concurrently. We found evidence for an own‐age bias in children, as well as for predicted delayed latencies and larger amplitudes for inverted faces, which replicates earlier findings. Finally, we extend recent reports about an expert‐sensitive component (P2) to other‐race faces to account for similar effects in regard to other‐age faces. We conclude that differences in neural activity are strongly related to the amount and quality of experience that participants have with faces of various ages. Effects of orientation are discussed in relation to the holistic hypothesis and recent data that compromise this view.
Social categories guide young children’s preferences for novel objects
Authors: Shutts Kristin , Banaji Mahzarin R. , Spelke Elizabeth S. 
Published: September 2009

AbstractTo whom do children look when deciding on their own preferences? To address this question, 3‐year‐old children were asked to choose between objects or activities that were endorsed by unfamiliar people who differed in gender, race (White, Black), or age (child, adult). In Experiment 1, children demonstrated robust preferences for objects and activities endorsed by children of their own gender, but less consistent preferences for objects and activities endorsed by children of their own race. In Experiment 2, children selected objects and activities favored by people of their own gender and age. In neither study did most children acknowledge the influence of these social categories. These findings suggest that gender and age categories are encoded spontaneously and influence children’s preferences and choices. For young children, gender and age may be more powerful guides to preferences than race.