Black Squares Research Articles

An Intersubunit Interaction between S4-S5 Linker and S6 Is Responsible for the Slow Off-gating Component in Shaker K+ Channels

Voltage-gated ion channels are controlled by the membrane potential, which is sensed by peripheral, positively charged voltage sensors. The movement of the charged residues in the voltage sensor may be detected as gating currents. In Shaker K(+) channels, the gating currents are asymmetric; although the on-gating currents are fast, the off-gating currents contain a slow component. This slow component is caused by a stabilization of the activated state of the voltage sensor and has been suggested to be linked to ion permeation or C-type inactivation. The molecular determinants responsible for the stabilization, however, remain unknown. Here, we identified an interaction between Arg-394, Glu-395, and Leu-398 on the C termini of the S4-S5 linker and Tyr-485 on the S6 of the neighboring subunit, which is responsible for the development of the slow off-gating component. Mutation of residues involved in this intersubunit interaction modulated the strength of the associated interaction. Impairment of the interaction still led to pore opening but did not exhibit slow gating kinetics. Development of this interaction occurs under physiological ion conduction and is correlated with pore opening. We, thus, suggest that the above residues stabilize the channel in the open state.

PW01-174 - Impaired fear conditioning to thermal pain stimuli in fibromyalgia patients - an experimental study

ObjectivePain is a complex experience that normally signals actual or potential tissue damage. Anticipatory anxiety to an unpredictable danger increases pain intensity and unpleasantness in healthy subjects. This study addressed the impact of anticipatory anxiety on pain perception in patients with chronic pain conditions for the first time.Method28 female subjects with chronic pain (14 fibromyalgia (FM), 14 rheumatoid arthritis (RA)) and 14 age-matched healthy controls (HC) underwent differential Pavlovian delay conditioning. Conditioned stimuli included visual stimuli (simple black squares and triangles) and were paired with thermal stimuli of low temperatures (CS-), and in a pseudorandomized way in the other half of the trials with high (CS+paired) or low temperatures (CS+unpaired) of 6 sec duration. The conditioned response was measured by pain/anxiety self-rating and heart rate changes.ResultsSubjects of the RA and HC, but not the FM group, rated the pain intensity of the same stimulus (low temperature) significantly higher in the unpredictable condition (CS+unpaired) than in the predictable condition (CS-). Mixed models analyses yielded a significant group-CS interaction with regard to anxiety, pain and heart rate in RA and HC, but not in FMConclusionsResults support impaired fear conditioning in FM including higher pain and anxiety perception even in save conditions compared to RA and HC. Since anxiety and anxiety-related behaviour may substantially contribute to the development and maintenance of chronic pain in FM, the results of this research may provide clues for further research in psychophysiology and psychological treatment in patients with FM.

Bi-National Allegory: Israel–Palestine and the Art of Larry Abramson

Bi-National Allegory: Israel–Palestine and the Art of Larry Abramson W. J. T. Mitchell (bio) W. J. T. Mitchell University of Chicago W. J. T. Mitchell W. J. T. Mitchell is Professor of English and Art History at the University of Chicago, and editor in chief of Critical Inquiry. His recent books include Cloning Terror: The War of Images, 9-11 to the Present, Critical Terms for Media Studies (with Mark Hansen), and What Do Pictures Want?, which won the Lowell Prize of the Modern Language Association in 2007. He is finishing a new book Teachable Moments in Race and Media, under contract to Harvard UP. Footnotes 1. I have learned, however, that this blemish is a Duchampian accident, perhaps a flaw in the photographic reproduction in the catalogue in which I re-viewed this painting. However, Abramson tells me chat Malevich’s original is now developing cracks, just like the old masters, and that his current returns to the black square are consequently exploring the issue of cracks and flaws. Sometimes chance leads the way to design. 2. The artist, as quoted in Daniella Talmor, “Eventus Nocturnus,” Larry Abramson: Eventus Nocturnus, trans. Hanita Rosenbluth (Haifa Museum of Art, 2001) 100. See also Gannit Ankori, “Bodies of Knowledge: The Art of Larry Abramson,” Larry Abramson: Eventus Nocturnus (Haifa Museum of Art, 2001). 3. Elyakim Chalakim is a name invented by the Israeli licensees of The Garbage Pail Kids, an American series of trading cards released in 1985 by the Topps Company, depicting grossly deformed kids and designed to parody the Cabbage Patch Kids dolls. In the English original the character dubbed Elyakim Chalakim was called Second Hand Rose, or Trashed Tracy. As chance had it, the name Elyakim (literally, in Hebrew, meaning “God will raise up, resurrect”) Chalakim (in Hebrew “parts, pieces”) could be read: God will resurrect the pieces. Even though the Israeli translator was probably only looking for a first name to rhyme with Chalakim, the resultant Elyakim Chalakim brings to mind the Kabbalist notion of “tikkun,” the mending of the shattered vessels that contained the divine light. In 1990 Abramson allegorically proclaimed Elyakim Chalakim “the great artist of the future,” by virtue of his will to “raise himself out of the surrounding wilderness of refuse and rehabilitate himself as a new axis of vertical meaning,” as quoted in Gideon Ofrat, “The Death of Elyakim,” Larry Abramson: Eventus Nocturnus, trans. Peretz Hidron (Haifa Museum of Art, 2001) 102. 4. From e-mail correspondence with the artist, February 22, 2010. 5. I have many reasons for using the phrase “Israel-Palestine” (or “Palestine-Israel”) to designate a hyphenated country that, from one point of view, only exists in the utopian image of a bi-national state, but from another point of view actually exists, and has existed for over half a century as a single administrative, governmental entity in which a population resides in a condition of radical inequality. But this would require an essay in itself. 6. See Mark Twain, Innocents Abroad: or The New Pilgrim’s Progress, 1869. 7. Despite the large body of commentary on Abramson’s work by Israeli critics and art historians, there has been little attention to the centrality of the political in his “abstract” and symbolic works. The political meaning of the crescent, which has been part of his work for the last twenty five years, has “never been seriously regarded,” according to the artist. E-mail correspondence, February 6, 2010. 8. Fredric Jameson, “Third World Literature in the Era of Multinational Capitalism,” Social Text 15 (Autumn 1986); 65–88. 9. Abramson’s work tsooba, made in 1993–1994 and exhibited in 1995 at the Kibbutz Art Gallery in Tel Aviv, was a groundbreaking critical dialogue with the role of abstract painting in the erasure of Palestinian memory from the landscape and its representations, tsooba included 38 25 × 25 cm oil on canvas landscape paintings after a photograph of the site of a deserted Palestinian village, 38 impressions of the wet landscape paintings on newspaper, and 13 still life paintings after samples of flora taken from the site. 10. When Golda Meir notoriously claimed that “there is no such thing...

Brain perfusion heterogeneity measurement based on Random Walk algorithm: Choice and influence of inner parameters

A Random Walk (RW) algorithm was designed to quantify the level of diffuse heterogeneous perfusion in brain SPECT images in patients suffering from systemic brain disease or from drug-induced therapy. The goal of the present paper is to understand the behavior of the RW method on different kinds of images (extrinsic parameters) and also to understand how to choose the right parameters of the RW (intrinsic parameters) depending on the image characteristics (i.e. SPECT images). “Extrinsic parameters” are related to the image characteristics (level/size of defect and diffuse heterogeneity) and “intrinsic” parameters are related to the parameters of the method (number ( N rw ) and length of walk ( L rw ), temperature ( T) and slowing parameter ( S)). Two successive studies were conducted to test the influence of these parameters on the RW result. In the first study, calibrated checkerboard images are used to test the influence of “extrinsic parameters” (i.e. image characteristics) on the RW result ( R-value). The R-value was tested as a function of (i) the size of black & white (B&W) squares simulating the size of a cortical defect, (ii) the intensity level gaps between the B&W squares simulating the intensity of the cortical defect and (iii) intensity (=variance) of noise, simulating the diffuse heterogeneity. The second study was constructed with simulated representative brain SPECT images, to test the “intrinsic” parameters. The R-value was tested regarding the influence of four parameters: S, T, N rw and L rw . The third study is constructed so as to see if the classification by diffuse heterogeneity of real brain SPECT images is the same if it's made by senior clinicians or by RW algorithm. Results Study 1: the RW was strongly influenced by all the characteristics of the images. Moreover, these characteristics interact with each other. The RW is influenced most by diffuse heterogeneity, then by intensity and finally by the size of a defect. Study 2: N rw and L rw values of 1000 give an optimal reproducibility of the measurement (mean standard deviation < 0.1), a fast computation time (time < 0.5 s/image) and have a maximum difference in terms of R-value between the two extreme images corresponding to the range of the population studied. The best S and T values for SPECT images are 3 and 15, respectively. Study 3: A significant correlation was found between RW ranking and the physicians’ consensus ( ρ = 0.789; p < 0.0001). Conclusion This study confirms that the RW method is able to measure the heterogeneity of brain SPECT images even in the presence of a large defect. However, the result of the method is strongly influenced by the “intrinsic” parameters, so the program should be calibrated for each different type of image.

Automatic Food Documentation and Volume Computation Using Digital Imaging and Electronic Transmission

Capturing accurate food intake data from participants enrolled in nutrition studies is essential for understanding relationships between diet and chronic disease (1). Numerous methods are employed to assess dietary intake such as food records, 24-hour recalls, or food frequency questionnaires. While each of these techniques is valuable, the error associated with each is unique. The food record requires a motivated participant, is tedious for some, places attention on the act of eating thus altering intake and is difficult for subjects with low literacy skills (2). Interviewing subjects about the previous day’s intake avoids the reactivity involved when recording current intake, but also requires the individual reporting intake to have good recall skills, knowledge of food names and ability to estimate amounts eaten; and requires a well-trained interviewer which makes this a costly process (2, 3). Food frequency questionnaires are limited by food lists and lack of detail regarding food preparation, and require respondents to summarize past intake over many months or the past year. Such instruments are known to contain significant measurement error (4). While all these methods provide valuable information about dietary intake, improving methodology even modestly would advance our knowledge about the influence of food intake on health. FIVR (Food Intake Visual and voice Recognizer), a subproject of the Genes, Environment, and Health Initiative from the National Institutes of Health (RFA-CA-07-032 at www.gei.nih.gov/index.asp), is designed to use new digital photographing technology to reduce measurement error associated with a food record. The intent is to create a tool that would both increase accuracy of intake records and reduce the recording burden for respondents. Using a mobile phone with a camera (Figure 1), the participant will photograph foods both before and after eating. In this way initial portion size is recorded as well as portions left uneaten. The photographs would be used to identify both the types and amounts of foods consumed. This paper briefly describes the technology and techniques involved. Figure 1 Typical Mobile Phone Interface showing (a). operator instruction screen, (b) menu of activities available and (c) camera poised to record meal. Creating sufficiently detailed images Capturing images of meals using a mobile phone presents its own unique challenges. Identifying foods from a picture requires a clear image; the automatic calculation of the amount eaten (volume) requires three or more clear images to be taken by the mobile phone user. Since a single image will not support estimation of food volume, rather 3-dimensional objects must be viewed at more than one angle (5, 6). The three images in Figure 2 are captured from 3 slightly different angles. A calibration object is also required in the images for determination of 3-dimensional size (see Figure 2). The calibration object (fiduciary marker) included in the images in Figure 2 is a card with black and white squares of known size. However, a standard credit card can be used to establish the relationship between size in image pixels and actual size of the object in milliliters. Images are also required before and after the meal is eaten to document the volume of food consumed. Figure 2 Three images captured by moving the camera using the FIVR mobile phone system. Quality of the image hinges on several factors including resolution (roughly indicated by number of pixels per image). Higher resolution (more pixels per image) creates larger files, which makes transferring images slower and more subject to failure, thus testing and refinement of the image details is integral to developing a successful system. Camera focus is critical since the best volumetric estimation is obtained when the three images are in focus and taken with the plate at the same distance from the camera. With fixed focus cameras, the images will be blurred if not taken at the right distance (which is often too great). With auto-focus cameras, the focusing is assured but the distance still must be maintained by the user. Ways to adjust the image to correct for small variations in distance are still being explored.

Enforcing temporal control of maternal mRNA translation during oocyte cell-cycle progression

Meiotic cell-cycle progression in progesterone-stimulated Xenopus oocytes requires that the translation of pre-existing maternal mRNAs occur in a strict temporal order. Timing of translation is regulated through elements within the mRNA 3' untranslated region (3' UTR), which respond to cell cycle-dependant signalling. One element that has been previously implicated in the temporal control of mRNA translation is the cytoplasmic polyadenylation element (CPE). In this study, we show that the CPE does not direct early mRNA translation. Rather, early translation is directed through specific early factors, including the Musashi-binding element (MBE) and the MBE-binding protein, Musashi. Our findings indicate that although the cyclin B5 3' UTR contains both CPEs and an MBE, the MBE is the critical regulator of early translation. The cyclin B2 3' UTR contains CPEs, but lacks an MBE and is translationally activated late in maturation. Finally, utilizing antisense oligonucleotides to attenuate endogenous Musashi synthesis, we show that Musashi is critical for the initiation of early class mRNA translation and for the subsequent activation of CPE-dependant mRNA translation.

In this issue

AbstractHsst! Histones rock!pp. 5437–5445Histones were a nuisance to molecular biologists in the early days – they were small, very basic, and did not do anything except neutralizing the charge on DNA. Then nucleosomes were discovered. Containing two sets of histones and a discrete chunk of DNA, they gave us structure. And now they give us targets. Transcriptional accessibility to DNA is regulated, in part, through the addition or removal of acetyl groups on histones. The work reported here by Naldi et al. examines the specificity and kinetics of drugs targeted at the histone deacetylases. This is complicated by the existence of three classes of HDACs: class I‐specific, class II‐specific, and non‐specific types of inhibitors. Each has a different pattern of effectiveness judged by hyperacetylation due to blocking of deacetylation. Over certain ranges of concentration, the inhibitors also affect cell progress through the cell cycle at specific transition points. magnified imageRound and round we go: Listeria monocytogenes in cells and outpp. 5484–5496Listeria monocytogenes has been recognized as a food‐borne pathogen for some time but is still not understood in a detailed proteomic fashion. Enter Van de Velde et al., with cultures stirring and centrifuges spinning, 2‐D DIGE gels running and MALDI power pulsing, asking “where?” and “how?” After identifying ∼400 spots out of ∼1600 resolved, some ∼200 answers have become at least partially visible. Of those, 60 were under‐expressed, with functions including stress defense and transport systems reduced. Over‐expressed were synthesis of cell envelope lipids, fatty acids, and glyceraldehyde‐3‐phosphate. A decrease in expression of D‐alanyl‐D‐alanine ligase reduced the thickness of the cell wall and rendered the cell wall more susceptible to ampicillin, an interesting potential opportunity for new drug. magnified imageCheckers anyone? (or draughts)pp. 5562–5566It seems that there is noise and there is noise – and then there is microarray noise. Structural noise, procedural noise, biological noise, and instrumental noise all contribute to the cacophony. To discern a change of 10% in levels of prostate‐specific antigen by conventional means required Anderson et al. to run 37 replicates. The power of the statistics increased dramatically when samples and controls were arrayed as checkers (samples on the red, controls on the black squares). As a result of the assay changes, CVs improved by 68% and required only two replicates for a 40% change and six replicates for a 10% change. It looks like they may deserve a king or two. magnified image

Cover Picture: Proteomics 24'09

AbstractHsst! Histones rock!Histones were a nuisance to molecular biologists in the early days – they were small, very basic, and did not do anything except neutralizing the charge on DNA. Then nucleosomes were discovered. Containing two sets of histones and a discrete chunk of DNA, they gave us structure. And now they give us targets. Transcriptional accessibility to DNA is regulated, in part, through the addition or removal of acetyl groups on histones. The work reported here by Naldi et al. examines the specificity and kinetics of drugs targeted at the histone deacetylases. This is complicated by the existence of three classes of HDACs: class I‐specific, class II‐specific, and non‐specific types of inhibitors. Each has a different pattern of effectiveness judged by hyperacetylation due to blocking of deacetylation. Over certain ranges of concentration, the inhibitors also affect cell progress through the cell cycle at specific transition points.Naldi, M. et al., Proteomics 2009, 9, 5437–5445.Round and round we go: Listeria monocytogenes in cells and outListeria monocytogenes has been recognized as a food‐borne pathogen for some time but is still not understood in a detailed proteomic fashion. Enter Van de Velde et al., with cultures stirring and centrifuges spinning, 2‐D DIGE gels running and MALDI power pulsing, asking “where?” and “how?” After identifying ∼400 spots out of ∼1600 resolved, some ∼200 answers have become at least partially visible. Of those, 60 were under‐expressed, with functions including stress defense and transport systems reduced. Over‐expressed were synthesis of cell envelope lipids, fatty acids, and glyceraldehyde‐3‐phosphate. A decrease in expression of D‐alanyl‐D‐alanine ligase reduced the thickness of the cell wall and rendered the cell wall more susceptible to ampicillin, an interesting potential opportunity for new drug.Van de Velde, S. et al., Proteomics 2009, 9, 5484–5496.Checkers anyone? (or draughts)It seems that there is noise and there is noise – and then there is microarray noise. Structural noise, procedural noise, biological noise, and instrumental noise all contribute to the cacophony. To discern a change of 10% in levels of prostate‐specific antigen by conventional means required Anderson et al. to run 37 replicates. The power of the statistics increased dramatically when samples and controls were arrayed as checkers (samples on the red, controls on the black squares). As a result of the assay changes, CVs improved by 68% and required only two replicates for a 40% change and six replicates for a 10% change. It looks like they may deserve a king or two.Anderson, T. et al., Proteomics 2009, 9, 5562–5566.

Retinal HDR images: Intraocular glare and object size

Abstract— Starting from measured scene luminances, the retinal images of high‐dynamic‐range (HDR) test targets were calculated. These test displays contain 40 gray squares with a 50% average surround. In order to approximate a natural scene, the surround area was made up of half‐white and half‐black squares of different sizes. In this display, the spatial‐frequency distribution approximates a 1/f function of energy vs. spatial frequency. Images with 2.7 and 5.4 optical density ranges were compared. Although the target luminances are very different, after computing the retinal image according to the CIE scatter glare formula, it was found that the retinal ranges are very similar. Intraocular glare strongly restricts the range of the retinal image. Furthermore, uniform, equiluminant target patches are spatially transformed to different gradients with unequal retinal luminances. The usable dynamic range of the display correlates with the range on the retina. Observers report that appearances of white and black squares are constant and uniform, despite the fact that the retinal stimuli are variable and non‐uniform. Human vision uses complex spatial processing to calculate appearance from retinal arrays. Spatial image processing increases apparent contrast with increased white area in the surround. Post‐retinal spatial vision counteracts glare.

Cargo surface hydrophobicity is sufficient to overcome the nuclear pore complex selectivity barrier

To fulfil their function, nuclear pore complexes (NPCs) must discriminate between inert proteins and nuclear transport receptors (NTRs), admitting only the latter. This specific permeation is thought to depend on interactions between hydrophobic patches on NTRs and phenylalanine-glycine (FG) or related repeats that line the NPC. Here, we tested this premise directly by conjugating different hydrophobic amino-acid analogues to the surface of an inert protein and examining its ability to cross NPCs unassisted by NTRs. Conjugation of as few as four hydrophobic moieties was sufficient to enable passage of the protein through NPCs. Transport of the modified protein proceeded with rates comparable to those measured for the innate protein when bound to an NTR and was relatively insensitive both to the nature and density of the amino acids used to confer hydrophobicity. The latter observation suggests a non-specific, small, and plant interaction network between cargo and FG repeats.

His Pupils' Nature

Natura Rochester Contemporary Art Center Rochester, New York February 6-March 22, 2009 John Pfahl's work is a tireless investigation of our perceptions, encompassing a variety of approaches but always with a keen awareness of the interaction of vision, images, and nature. His series Permutations on the Picturesque (1993-99) challenged the pixel's view of the landscape at a time when digital photography was just breaking through the soil, while his series Picture Windows (1978-81) framed the way we likely spend the most time seeing nature: gazing through panes of glass. An instructor at the Rochester Institute of Technology (RIT) from 1968 through 1985, Pfahl presided over the development of hundreds of imagemakers. Co-curated by Pfahl and RIT's Therese Mulligan, this exhibition is the latest installment in Rochester Contemporary Art Center's Maker/Mentor series and features Pfahl's work alongside that of fifteen former students, many of whom are now teachers themselves. Nonetheless, their works bear the indelible influence of Pfahl and his fascination with the intersection of images and nature. [ILLUSTRATION OMITTED] A selection of tall, narrow prints from Pfahl's current Scrolls series (2006) sets the tone of the exhibition. His latest landscape alterations feature vistas digitally stretched to a shape resembling long, vertical, Asian scrolls. In the process, elements of the scene are lengthened, taking on new shapes and associations. In twilight in the wilderness (adirondacks) (2006), an elongated cloud pours down through the blue sky, oddly exhibiting a visual heft not seen in the diminutive and distant mountain range. Reeds in the placid swamp of autumn lagoon, braddock bay (2007) have the plasticity of pulled taffy when seen individually; when tightly packed, these wispy strands of grass read as rock solid. In Pfahl's hands, images of jagged peaks and scarlet sunsets--scenes commonly offered as simple celebrations of seeing--become a challenge to our methods of perception. The work of Pfahl's former students is a diverse lot that strongly declares its independent vision in a voice accented by the dialect of the teacher. Stances run the gamut: nature as a sanctuary, a slaughterhouse, a mystery, an oddity. The process of curious looking permeates the show, including commentary on the challenges of using the photographic machine to record the organic world. Grey Crawford's prints of flowers and foliage are confections of hardened sugar syrup, full of brash, squint-inducing color. Circular, lens-like shapes (all through his Blossoms #2 (2008) and Blossoms #5 (2008), focusing or blurring what lies beyond. Like Pfahl's Scrolls, Crawford reworks a worn photographic cliche--the close-up of the pretty flower--into a think piece on tools and processes. Following this thread, Jeannie Pierce's work presents head-and-shoulder shots of birds as if viewed through a sailor's collapsing scope. The round images float in a black square, reminding us that image technology corrals the natural, circular view of the lens into more aesthetically traditional squares and rectangles. Nature has long attracted collectors; two selections address the spoils of those likely to ignore the naturalist adage Take nothing but a picture. Alida Fish's series From the Cabinet of Curiosities (2007) shows us aquatic life whose now-waterless existence is devoted to amusing visitors to someone's Wunderkammer. Both the sea creatures and the photographs are beautiful objects; you'll become engrossed in the hard sponge texture of Horned Fish (2008) as rendered in the smooth, creamy grays of Fish's flawless tintypes. Silvia Lizama's work features marine dwellers that have become kitsch, are mounted to walls, or weigh down papers on a desk. Lizama hand-colors her gelatin silver prints--a method that generally ranges from distracting to worse. But her use of coral, seafoam, and other maritime hues are amazingly subtle, inspiring a double take upon realizing they are not, in fact, color photographs. …

Correction: The Burden of Mycobacterial Disease in Ethiopian Cattle: Implications for Public Health

The black square symbols in Table 4 appear incorrectly. Please view the correct Table 4 here:

A novel method for the identification of weave repeat through image processing

Conventionally, weave repeat is identified manually by extracting individual warp or weft yarns from the fabric. This process can be troublesome and time-consuming. Therefore, automatic methods capable of identifying woven fabric repeat can be very useful. This paper describes the application of a new algorithm using image processing techniques for the development of an automatic method, capable of identifying weave repeat. This method is based on scanning and obtaining a gray scale image of the original sample and enhancing it by morphological operations. The enhanced image is filtered by steerable vertical filters and then segmented into blocks showing either a warp or a weft point. The blocked image is divided into specific sub images, followed by operating sum over their columns and forming a matrix from them. A primary and secondary threshold is then defined giving rise to the formation of the weave pattern in the form of black and white squares. To identify the weave repeat, a matrix, replacing the black and white squares of the weave pattern by zero and one is produced. Then the first repeating row and column are found, showing the start of the next repeat vertically and horizontally, leading to the identification of weave repeat.

Critical Roles of Subunit NuoH (ND1) in the Assembly of Peripheral Subunits with the Membrane Domain of Escherichia coli NDH-1

The bacterial proton-translocating NADH:quinone oxidoreductase (NDH-1) consists of two domains, a peripheral arm and a membrane arm. NuoH is a counterpart of ND1, which is one of seven mitochondrially encoded hydrophobic subunits, and is considered to be involved in quinone/inhibitor binding. Sequence comparison in a wide range of species showed that NuoH is comprehensively conserved, particularly with charged residues in the cytoplasmic side loops. We have constructed 40 mutants of 27 conserved residues predicted to be in the cytoplasmic side loops of Escherichia coli NuoH by utilizing the chromosomal DNA manipulation technique and investigated roles of these residues. Mutants of Arg(37), Arg(46), Asp(63), Gly(134), Gly(145), Arg(148), Glu(220), and Glu(228) showed low deamino-NADH-K(3)Fe(CN)(6) reductase activity, undetectable NDH-1 in Blue Native gels, low contents of peripheral subunits (especially NuoB and NuoCD) bound to the membranes, and a significant loss of the membrane potential and proton-pumping function coupled to deamino-NADH oxidation. The results indicated that these conserved residues located in the cytoplasmic side loops are essential for the assembly of the peripheral subunits with the membrane arm. Implications for the involvement of NuoH (ND1) in maintaining the structure and function of NDH-1 are discussed.

HIV–host interactions: a map of viral perturbation of the host system

Since the 1980s, the rapid progression of the HIV/AIDS pandemic has prompted a major international research effort. As a result, the current knowledge on HIV biology, its evolution, and origins [1–5] exceeds that of many, if not all, other viruses. One of the most important areas of HIV research is the detailed understanding of HIV replication. As with all viruses, HIV must exploit the host’s cellular machinery and metabolism to copy its genetic material, synthesize viral proteins, and assemble new virions. The viral replication cycle is thus dependent on an intricate network of direct and indirect protein interactions: between the viral proteins, between the virus and the host, and ultimately between the various host proteins that constitute the subverted cellular systems. When we also take into account the host’s immune response and intrinsic antiviral factors, there are clearly a large number of host–pathogen relationships that are important to our full understanding of HIV biology. However, until recently [6], this valuable information has remained ‘locked’ in the published literature, making it time-consuming to study by individual researchers and inaccessible to computational analysis, thus hindering the progress of research. Here we highlight new developments in the area of host–pathogen systems biology that in our opinion will provide helpful insights to the HIVresearch community.

Visuoperceptual deficits in letter-by-letter reading?

A longstanding and controversial issue concerns the underlying mechanisms that give rise to letter-by-letter (LBL) reading: while some researchers propose a prelexical, perceptual basis for the disorder, others postulate a postlexical, linguistic source for the problem. To examine the nature of the deficit underlying LBL reading, in three experiments, we compare the performance of seven LBL readers, matched control participants and one brain-damaged patient, OL, with no reading impairment. Experiment 1 revealed that the LBL patients were impaired, relative to the controls and to OL, on a same/different matching task using checkerboards of black and white squares. Given that the perceptual impairment extends beyond abnormalities with alphanumeric stimuli, the findings are suggestive of a more general visual processing deficit. This interpretation was confirmed in Experiments 2 (matching words and symbol strings) and 3 (visual search of letter and symbol targets), which compared the processing of linguistic and non-linguistic written stimuli, matched for visual complexity. In both experiments, the LBL patients displayed qualitatively similar effects of length and left-to-right sequential ordering on linguistic and non-linguistic stimuli. Moreover, there was a clear association between the perceptual impairments on these tasks and the slope of the reading latency function for the LBL patients. Taken together, these findings are consistent with a significant visuoperceptual impairment in LBL that adversely affects reading performance as well as performance on other non-reading tasks.

Purinergic P2X7 Receptors Mediate ATP-induced Saliva Secretion by the Mouse Submandibular Gland

Salivary glands express multiple isoforms of P2X and P2Y nucleotide receptors, but their in vivo physiological roles are unclear. P2 receptor agonists induced salivation in an ex vivo submandibular gland preparation. The nucleotide selectivity sequence of the secretion response was BzATP >> ATP > ADP >> UTP, and removal of external Ca(2+) dramatically suppressed the initial ATP-induced fluid secretion ( approximately 85%). Together, these results suggested that P2X receptors are the major purinergic receptor subfamily involved in the fluid secretion process. Mice with targeted disruption of the P2X(7) gene were used to evaluate the role of the P2X(7) receptor in nucleotide-evoked fluid secretion. P2X(7) receptor protein and BzATP-activated inward cation currents were absent, and importantly, purinergic receptor agonist-stimulated salivation was suppressed by more than 70% in submandibular glands from P2X(7)-null mice. Consistent with these observations, the ATP-induced increases in [Ca(2+)](i) were nearly abolished in P2X(7)(-/-) submandibular acinar and duct cells. ATP appeared to also act through the P2X(7) receptor to inhibit muscarinic-induced fluid secretion. These results demonstrate that the ATP-sensitive P2X(7) receptor regulates fluid secretion in the mouse submandibular gland.

A Study on the Comparison of the Glam and Punk Make-up - Focused on the 1970s -

【Popular music unites people who have different genders, ages, locals, and values. Through the popular music, youth interchange their emotion and create their fashion. Fashion and music formed the twin pillars on which the first historically significant youth sub-culture was built. Glam rock and Punk rock which won popularity in the 1970s influenced the fashion of the times. The purpose of this study is to compare Glam and Punk make-up which appeared as a symbol of the rebel against an older generation. The methodology utilized in this study was the analysis of materials from the survey through the literature, internet sites, and visual references. The results of this study are as follows: In face make-up, Glam used a white base to appear cosmic; on the other hand, Punk used a white base to appear pale and horrid. In eye make-up, Glam used black, pink, and blue eye shadow, and accented the eye by using black eye lines. Punk used black eye shadow, and drew black circles or squares around eyes. In lip make-up, Glam used pink, purple, red, and black lip color and silver and pink lip gloss to glitter. Punk used red and black lip color to appear horrid. In body make-up, Glam used glitter powder to appear with a bright skin. Punk drew tattoos and horror patterns in their body. The common themes of Glam and Punk make-up were rebellion, androgyny, and the beauty of ugliness as well as a self-created persona.】

Diverting attention with tactile stimuli: an MMN study on audiovisual processing

Event Abstract Back to Event Diverting attention with tactile stimuli: an MMN study on audiovisual processing Hao T. Ho1*, D. T. Nguyen2, B. Pleger2 and S.A Kotz1 1 Max Planck Institute for Human Cognitive and Brain Sciences, Germany 2 Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences, Germany Audiovisual processing has recently received increased attention in neuropsychological research. Of particular interest is the question whether the binding of auditory and visual information can occur outside the focus of attention. In this context, the Mismatch Negativity (MMN) proves to be a useful measure as its elicitation has been shown to be mainly unaffected by attention. However, the mere elicitation of the MMN is insufficient to prove that a certain process occurs pre-attentively. In addition, participants’ attention must be directed away from the stimuli at test. This is usually achieved by asking the participants to perform a task in another modality, e.g. reading a book, while being stimulated auditorily. When investigating audiovisual processing, controlling participants' attentional state poses a problem, as conventional methods involve either the auditory or visual modality. Therefore, to divert participants’ attention in an audiovisual MMN experiment we employed tactile stimulation. The tactile stimuli were generated with a 4x4 Grid Braille-Module (ca. 70 mm2) consisting of 16 extendable plastic pins (width: ca. 1mm, height: up to 1.5 mm, not pointy). In four blocks the participants were presented (1) auditory (standards: 400 Hz, 600 Hz; deviants: 480 Hz, 680 Hz), (2) visual (standards: black square, black circle; deviants: grey square, grey circle), and (3-4) audiovisual stimuli (standards: black square + 400 Hz, black circle + 600 Hz; deviants: black square + 600 Hz, black circle + 400 Hz; standards and deviants were then switched) according to an oddball paradigm (85% standards, 15 % deviants). At the same time they performed a one-back task on tactile stimuli (vertical and horizontal lines presented in random order). The participants were instructed to respond as fast as possible whenever a horizontal or vertical line was repeated. In two additional blocks (5-6), the participants carried out a one-back task in the visual and auditory modality, while receiving stimulation in the auditory and visual modality respectively. Similar to the one-back task on tactile stimuli, they had to respond whenever a black square or a black circle was repeated in the case of the visual one-back task. For the auditory one-back task, the participants had to react whenever a tone (400 Hz or 600 Hz) was repeated. The successful diversion of participants’ attention through tactile stimulation may be a new venue for studies that want to explore the pre-attentive nature of audiovisual processing. Conference: MMN 09 Fifth Conference on Mismatch Negativity (MMN) and its Clinical and Scientific Applications, Budapest, Hungary, 4 Apr - 7 Apr, 2009. Presentation Type: Poster Presentation Topic: Poster Presentations Citation: Ho HT, Nguyen DT, Pleger B and Kotz S (2009). Diverting attention with tactile stimuli: an MMN study on audiovisual processing. Conference Abstract: MMN 09 Fifth Conference on Mismatch Negativity (MMN) and its Clinical and Scientific Applications. doi: 10.3389/conf.neuro.09.2009.05.103 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 26 Mar 2009; Published Online: 26 Mar 2009. * Correspondence: Hao T Ho, Max Planck Institute for Human Cognitive and Brain Sciences, Leipzig, Germany, htho@cbs.mpg.de Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Hao T Ho D. T Nguyen B. Pleger S.A Kotz Google Hao T Ho D. T Nguyen B. Pleger S.A Kotz Google Scholar Hao T Ho D. T Nguyen B. Pleger S.A Kotz PubMed Hao T Ho D. T Nguyen B. Pleger S.A Kotz Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

The Effect of Simulated Cataracts on Drivers’ Hazard Perception Ability

We investigated the extent to which simulated cataracts slow a driver's ability to anticipate potential traffic hazards, a skill that has been found to correlate with crash risk. In previous studies, we found a significant correlation between contrast sensitivity and hazard perception in a sample of older drivers. The present study allowed us to determine the causal direction of this relationship. This is important as it provides a better understanding of the mechanisms underlying the higher crash risk of drivers with cataracts. One hundred eighty-six drivers with normal vision completed a validated video-based hazard perception driving test, designed to measure hazard anticipation response times in dynamic scenes. They also completed a change detection task based on traffic hazards, which was designed to measure object detection times in static scenes. Participants undertook the tasks wearing either mild or moderate cataract simulation goggles, or wearing goggle frames without lenses. Participants wearing moderate simulated cataract goggles were slower than the control group in both the hazard perception test, t(98.50) = -3.71, p < 0.001, and the hazard change detection task, t(124) = -13.86, p < 0.001. Participants with the mild simulated cataract goggles were slower than the control group in the hazard change detection task, t(114) = -4.04, p < 0.001, but not the hazard perception test, t(114) = -1.33, p = 0.19. Moderate levels of simulated cataract slowed drivers' ability to detect and anticipate traffic hazards enough to warrant road safety concerns, despite the fact that the vision of participants wearing the cataract goggles still complied with the minimum legal standard required for driving.