FEBS JOURNAL, Issue 3 2002
Christoph Böhme
The structure of post-translational modifications of human heparin cofactor II isolated from human serum and from recombinant Chinese hamster ovary cells and their effects on heparin binding have been characterized. Oligosaccharide chains were found attached to all three potential N-glycosylation sites in both protein preparations. The carbohydrate structures of heparin cofactor II circulating in blood are complex-type diantennary and triantennary chains in a ratio of 6 : 1 with the galactose being > 90% sialylated with ,2,6 linked N-acetylneuraminic acid. About 50% of the triantennary structures contain one sLex motif. Proximal ,1,6 fucosylation of oligosacharides from Chinese hamster ovary cell-derived HCII was detected in >,90% of the diantennary and triantennary glycans, the latter being slightly less sialylated with exclusively ,2,3-linked N -acetylneuraminic acid units. Applying the ESI-MS/ MS-MS technique, we demonstrate that the tryptic peptides comprising tyrosine residues in positions 60 and 73 were almost completely sulfated irrespective of the protein's origin. Treatment of transfected Chinese hamster ovary cells with chlorate or tunicamycin resulted in the production of heparin cofactor II molecules that eluted with higher ionic strength from heparin,Sepharose, indicating that tyrosine sulfation and N-linked glycans may affect the inhibitor's interaction with glycosaminoglycans. [source]

Omalizumab decreases nonspecific airway hyperresponsiveness in vitro

ALLERGY, Issue 2 2007
P. Berger
Background:, In asthmatic patients, both symptoms and hyperresponsiveness are related to immunoglobulin E (IgE) concentration in serum. The anti-IgE monoclonal antibody omalizumab improved the control of asthma, but its effect on airway hyperresponsiveness is controversial. Passive sensitization reproduced in vitro a bronchial hyperresponsiveness, an increase in IgE bearing cells, and a mast cell degranulation. This study was designed to examine the effect of omalizumab on passive sensitization-induced hyperresponsiveness, alterations in IgE positive inflammatory cells and mast cell degranulation within the bronchial wall. Methods:, Proximal (3,5 mm diameter) and distal (0.5,1.5 mm diameter) human bronchi dissected out from 10 lung specimens were incubated in normal or asthmatic serum containing various concentrations of omalizumab. Contractile responses to histamine or Dermatophagoides pteronyssinus (D. pter) were recorded using an organ bath system and expressed as percentage of maximal contractile response to acetylcholine (ACh). Immunohistochemistry was performed using monoclonal antibodies directed against IgE or tryptase. Mast cells were classified as fully granulated (type I), partly (type II) or largely degranulated (type III). Results:, The specific bronchial hyperresponsiveness to D. pter and the nonspecific bronchial hyperresponsiveness to histamine following passive sensitization were significantly inhibited by omalizumab in both distal and proximal airways. Passive sensitization-induced increase in IgE positive cells was also abolished by omalizumab in a concentration dependent manner. Mast cell degranulation which was inhibited by omalizumab was positively correlated with the contractile response to D. pter. Conclusions:, Omalizumab blocks specific and nonspecific bronchial hyperresponsiveness. Anti-IgE also decreases IgE bearing cell number and mast cell degranulation. [source]

Proximal and uniform convergence on apartness spaces

MLQ- MATHEMATICAL LOGIC QUARTERLY, Issue 3 2003
Lumini, a Simona Vî
Abstract The main purpose of this paper is to investigate constructively the relationship between proximal convergence, uniform sequential convergence and uniform convergence for sequences of mappings between apartness spaces. It is also shown that if the second space satisfies the Efremovic axiom, then proximal convergence preserves strong continuity. [source]

The effect of mosapride citrate on proximal and distal colonic motor function in the guinea-pig in vitro

NEUROGASTROENTEROLOGY & MOTILITY, Issue 2 2008
H. S. Kim
Abstract, Mosapride citrate (mosapride), a substituted benzamide, is a selective 5-HT4 receptor agonist, and is known to have prokinetic properties on the stomach. However, it is unclear whether mosapride also has a prokinetic effect on the colon. We previously found that mosapride significantly shortened colonic transit time in the guinea-pig, an animal with a distribution of colonic 5-HT4 receptors similar to that of a human. So, we aimed to separately evaluate the effect of mosapride on proximal and distal colonic motor function in the guinea-pig. Proximal (approximately 8 cm from the ileocolic junction) and distal colon (approximately 8 cm from the anus) were removed. Both ends of the colon were connected to a chamber containing a Krebs-Henseleit solution. To measure colonic transit time, artificial faeces were inserted into the oral side of the lumen and moved towards the anal side by intraluminal perfusion via a peristaltic pump. A total of 6 cm of transit was observed and time was measured in 2 cm increments. A tissue bath study, using electrical stimulation, was performed to estimate the contractile activity of the circular musculature of the colon. Immunohistochemical staining for 5-HT4 receptors was performed in the myenteric plexus and circular muscle in both proximal and distal colon, and the stained area was measured using a microscope and computer software. Mosapride enhanced contraction at 10,9 to 10,7 mol L,1, coinciding with rapid transit both in proximal and distal colon. This pattern was more prominent in proximal colon. At the high dose (10,6 mol L,1) mosapride had little or no effect on colonic contraction. This stimulatory effect was attenuated by GR113808, atropine and tetrodotoxin. In the myenteric plexus, the density of 5-HT4 receptors was significantly greater in the proximal colon than in the distal colon, but in circular muscle the density was greater in the distal colon. Thus, mosapride accelerates transit through increased contraction in the proximal colon more than distal colon. The different distribution of neuronal and muscular 5-HT4 receptors may support these findings. Therefore, mosapride may be a useful alternative to tegaserod and cisapride for constipation. [source]

The genes encoding bovine SP-A, SP-D, MBL-A, conglutinin, CL-43 and CL-46 form a distinct collectin locus on Bos taurus chromosome 28 (BTA28) at position q.1.8,1.9

ANIMAL GENETICS, Issue 4 2004
M. Gjerstorff
Summary Collectins are a group of C-type lectins involved in the innate immune system, where they mediate and modulate clearance of pathogens. The health status of cattle is of major economical and ethical concern; therefore, the study of bovine collectins is of importance. The collectins conglutinin, CL-43 and CL-46 are only present in Bovidae and the characterization of their genes indicates that they are structural descendants of another collectin, lung surfactant protein D (SP-D). In this study, we assembled BAC clones into a contig spanning 330,1150 kb, which includes the bovine genes encoding the collectins SP-A (SFTPA), SP-D (SFTPD), mannan-binding lectin A (MBL1), CL-43 (COLEC9), CL-46 (COLEC13) and conglutinin (COLEC8). In the same contig, we also identified a gene that potentially encodes a novel conglutinin-like collectin (COLEC14). The arrangement of STFPA, SFTPD and MBL1 is homologous to the organization found in humans and mice, whereas the Bovidae-specific collectin genes, COLEC8, COLEC9 and COLEC13, extend from SFTPD. Proximal to the collectin locus at BTA28q1.8,1.9, and included in the contig, we found the microsatellite IDVGA8, which may be a valuable marker for tracking polymorphisms in the linked collectin genes. [source]

Outcome following bypass, and proximal and distal ligation of popliteal aneurysms

BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue 2 2007
B. Box
Background: The aim of this study was to describe early and late results of proximal and distal ligation for popliteal aneurysm (PA), combined with bypass, with particular reference to the fate of the excluded aneurysm. Methods: Of a cohort of 116 patients with PAs, 66 were treated with bypass and ligation. Graft patency was determined by duplex surveillance. In addition, 17 patients with bypassed PAs underwent a total of 33 duplex scans to determine flow within the aneurysm and change in size. Results: For initially patent PAs, 3-, 5- and 8-year primary bypass graft patency was 78, 78 and 51 per cent respectively. These rates were not statistically significantly different from those following bypass for thrombosed PA, 3- and 5-year primary patency being 72 and 65 per cent respectively. No PA produced further symptoms after bypass and ligation. No flow was seen in any aneurysm at follow-up. Only one showed an increase in size. Conclusion: Proximal and distal ligation with bypass produced satisfactory long-term patency with good exclusion of the PA. Copyright © 2006 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd. [source]

Intraductal carcinoma component as a favorable prognostic factor in biliary tract carcinoma

CANCER SCIENCE, Issue 1 2009
Hidenori Ojima
The aim of this study is to evaluate the prognostic impact of an intraductal carcinoma component and bile duct resection margin status in patients with biliary tract carcinoma. An intraductal carcinoma component was defined as carcinoma within the bile duct outside the main tumor nodule consisting of a subepithelial invasive component. Surgically resected materials from 214 patients were evaluated by histological observations. Seventy-nine patients (36.9%) with an intraductal carcinoma component infrequently developed large tumors and infrequently showed deep invasion and venous, lymphatic and perineural involvement in the main tumor nodule. An intraductal carcinoma component was inversely correlated with advanced clinical stage, and was shown to be a significantly favorable prognostic factor by both univariate and multivariate analyses. Proximal (hepatic) side bile duct resection margin status was categorized into negative for tumor cells, positive with only an intraductal carcinoma component [R1 (is)], and positive with a subepithelial invasive component (R1). Forty-five patients (21.0%) with an R1 resection margin had a poorer prognosis than 148 patients (69.2%) with a negative resection margin, whereas 21 patients (9.8%) with an R1 (is) resection margin did not. In patients with an R1 resection margin, the risk of anastomotic recurrence was higher, and the period until anastomotic recurrence was shorter, than in patients with an R1 (is) resection margin. Surgeons should not be persistent in trying to achieve a negative surgical margin when the intraoperative frozen section diagnosis is R1 (is), and can choose a safe surgical procedure to avoid postoperative complications. (Cancer Sci 2009; 100: 62,70) [source]

ChemInform Abstract: Substrate-Controlled Selective Proximal and Distal C,C Bond Cleavage via Lewis Acid Mediated O-Acylation of 2-(Arylmethylene)cyclopropylaldehyde: A Stereoselective Synthesis of Bifunctional Methylenecyclobutanes and 1,3-Conjugated Dienes.

CHEMINFORM, Issue 3 2009
Xian Huang
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

Protective mechanisms of the common fibular nerve in and around the fibular tunnel: A new concept

CLINICAL ANATOMY, Issue 6 2009
Ramadan M. El Gharbawy
Abstract The most frequent site at which the common fibular nerve is affected by compression, trauma, traction, masses, and surgery is within and around the fibular tunnel. The aim of this study was to determine whether there were protective mechanisms at this site that guard against compression of the nerve. Twenty-six lower limbs of 13 preserved adult cadavers (11 males and two females) were used. Proximal to the entrance of the tunnel, three anatomical configurations seemed to afford the required protection for the nerve: reinforcement of the deep fascia; tethering of the common fibular nerve to both the tendon of the biceps femoris and the reinforced fascia; and the particular arrangement of the deep fascia, fibular head, and soleus and gastrocnemius muscles. At the entrance of the tunnel, contraction of the first segment of fibularis longus muscle could afford the required protection. In the tunnel, contraction of the second and third segments of fibularis longus muscle could guard against compression of the nerve. The tough fascia on the surface of fibularis longus muscle and the fascial band within it, which have long been accused of compression of the nerve, may actually be elements of the protective mechanisms. We conclude that there are innate, anatomical protective mechanisms which should be taken into consideration when decompressing the common fibular nerve. To preserve these mechanisms whenever possible, the technique should be planned and varied according to the underlying etiology. Clin. Anat. 22:738,746, 2009. © 2009 Wiley-Liss, Inc. [source]

Cor Triatriatum Sinister with and without Left Ventricular Inflow Obstruction: Visualization of the Entire Supravalvular Membrane by Real-time Three-dimensional Echocardiography.

CONGENITAL HEART DISEASE, Issue 6 2006
Impact on Clinical Management of Individual Patient
ABSTRACT We present 4 cases of cor triatriatum in whom the diagnosis was correctly made by 2-dimensional transthoracic echocardiography, which showed the supravalvular left atrial membrane that divides the left atrium into 2 chambers. The pulmonary veins were connected normally to the proximal left atrial chamber and the left atrial appendage was connected to the distal left atrial chamber. In 1 patient there was evidence of severe pulmonary venous obstruction to the mitral valve by Doppler examination, while in the other three, there was no venous obstruction. Patients were then examined by real-time 3-dimensional echocardiography (RT3DE, using ×4 matrix array transducer connected to Sonos 7500 echocardiographic system Phillips, Andover, Mass, USA). This showed the exact morphology of the membrane and led to cancellation of planed surgical intervention in 1 case in which the membrane was only a broad band crossing the left atrial cavity. In addition to delineating the exact morphology of the intracavitary anomaly, this novel echocardiographic imaging modality should be an additive tool to better understand the natural history of these nonobstructive left atrial membranes via longitudinal follow-up of these patients. [source]

The heel and toe of the cell's foot: A multifaceted approach for understanding the structure and dynamics of focal adhesions

CYTOSKELETON, Issue 11 2009
Haguy Wolfenson
Abstract Focal adhesions (FAs) are large clusters of transmembrane receptors of the integrin family and a multitude of associated cytoplasmic "plaque" proteins, which connect the extracellular matrix-bound receptors with the actin cytoskeleton. The formation of nearly stationary FAs defines a boundary between the dense and highly dynamic actin network in lamellipodium and the sparser and more diverse cytoskeletal organization in the lamella proper, creating a template for the organization of the entire actin network. The major "mechanical" and "sensory" functions of FAs; namely, the nucleation and regulation of the contractile, myosin-II-containing stress fibers and the mechanosensing of external surfaces depend, to a major extent, on the dynamics of molecular components within FAs. A central element in FA regulation concerns the positive feedback loop, based on the most intriguing feature of FAs; that is, their dependence on mechanical tension developing by the growing stress fibers. FAs grow in response to such tension, and rapidly disassemble upon its relaxation. In this article, we address the mechanistic relationships between the process of FA development, maturation and dissociation and the dynamic molecular events, which take place in different regions of the FA, primarily in the distal end of this structure (the "toe") and the proximal "heel," and discuss the central role of local mechanical forces in orchestrating the complex interplay between FAs and the actin system. Cell Motil. Cytoskeleton 66: 1017,1029, 2009. © 2009 Wiley-Liss, Inc. [source]

Differential expression and localization of neuronal intermediate filament proteins within newly developing neurites in dissociated cultures of Xenopus laevis embryonic spinal cord

CYTOSKELETON, Issue 1 2001
Jayanthi Undamatla
Abstract The molecular subunit composition of neurofilaments (NFs) progressively changes during axon development. In developing Xenopus laevis spinal cord, peripherin emerges at the earliest stages of neurite outgrowth. NF-M and XNIF (an ,-internexin-like protein) appear later, as axons continue to elongate, and NF-L is expressed after axons contact muscle. Because NFs are the most abundant component of the vertebrate axonal cytoskeleton, we must understand why these changes occur before we can fully comprehend how the cytoskeleton regulates axon growth and morphology. Knowing where these proteins are localized within developing neurites and how their expression changes with cell contact is essential for this understanding. Thus, we examined by immunofluorescence the expression and localization of these NF subunits within dissociated cultures of newly differentiating spinal cord neurons. In young neurites, peripherin was most abundant in distal neuritic segments, especially near branch points and extending into the central domain of the growth cone. In contrast, XNIF and NF-M were usually either absent from very young neurites or exhibited a proximal to distal gradient of decreasing intensity. In older neurites, XNIF and NF-M expression increased, whereas that of peripherin declined. All three of these proteins became more evenly distributed along the neurites, with some branches staining more intensely than others. At 24 h, NF-L appeared, and in 48-h cultures, its expression, along with that of NF-M, was greater in neurites contacting muscle cells, arguing that the upregulation of these two subunits is dependent on contact with target cells. Moreover, this contact had no effect on XNIF or peripherin expression. Our findings are consistent with a model in which peripherin plays an important structural role in growth cones, XNIF and NF-M help consolidate the intermediate filament cytoskeleton beginning in the proximal neurite, and increased levels of NF-L and NF-M help further solidify the cytoskeleton of axons that successfully reach their targets. Cell Motil. Cytoskeleton 49:16,32, 2001. © 2001 Wiley-Liss, Inc. [source]

The "Modified" Winch Stitch

DERMATOLOGIC SURGERY, Issue 10 2001
J. Michael Casparian MD
Background. The methods described to achieve intraoperative tissue expansion have drawbacks. Objective. To report an intraoperative tissue expansion technique using standard suture material and hemostats to create a "modified" winch stitch. Methods. A continuous running suture is placed with both ends left free. A "fixed" hemostat is placed above the skin at one end. After pulling at the other end with a second hemostat, a third hemostat is placed proximal to this hemostat just above the skin, which is left in place to produce stretching. The second and third hemostats are then used in an alternating pulling and holding fashion. Results. This method produces significant tissue expansion. If the desired degree of approximation is achieved, the ends of the suture can be tied together, as in the previously described winch stitch. Conclusion. The modified winch stitch is a simple and inexpensive means to facilitate closure of wounds under a significant amount of tension. [source]

Involvement of canonical Wnt/Wingless signaling in the determination of the positional values within the leg segment of the cricket Gryllus bimaculatus

DEVELOPMENT GROWTH & DIFFERENTIATION, Issue 2 2007
Taro Nakamura
The cricket Gryllus bimaculatus is a hemimetabolous insect whose nymphs posses the ability to regenerate amputated legs. Previously, we showed that Gryllus orthologues of Drosophila hedgehog (Gb'hh), wingless (Gb'wg) and decapentaplegic (Gb'dpp) are expressed during leg regeneration and play essential roles in the establishment of the proximal-distal axis. Here, we examined their roles during intercalary regeneration: when a distally amputated tibia with disparate positional values is placed next to a proximally amputated host, intercalary growth occurs in order to regenerate the missing part. In this process, we examined expression patterns of Gb'hh and Gb'wg. We found that expressions of Gb'hh and Gb'wg were induced in a regenerate and the host proximal to the amputated region, but not in the grafted donor distal to the regenerate. This directional induction occurs even in the reversed intercalation. Because these results are consistent with a distal-to-proximal respecification of the regenerate, Gb'wg may be involved in the re-establishment of the positional values in the regenerate. Furthermore, we found that no regeneration occurs when Gb'armadillo (the orthologue of beta-catenin) was knocked down by RNA interference. These results indicate that the canonical Wnt/Wingless signaling pathway is involved in the process of leg regeneration and determination of positional information in the leg segment. [source]

Requirement for ,B1-crystallin promoter of Xenopus laevis in embryonic lens development and lens regeneration

DEVELOPMENT GROWTH & DIFFERENTIATION, Issue 3 2005
Nobuhiko Mizuno
Regulation of the lens-specific ,B1-crystallin promoter in Xenopus laevis was investigated using transgenic larvae and tadpoles. Comparison of the promoter sequence with that of chicken ,B1-crystallin gene indicates significant sequence similarity over a span of several hundred base pairs starting from the transcriptional start site. Remarkably, PL-1 and PL-2 sequences identified in the chicken promoter as essential binding sites of MAF, Pax6 and Prox1 transcription factors were conserved. Mutations of X (Xenopus) PL-1 and XPL-2 sequences eliminated the promoter activity, indicating a conserved mechanism regulating ,B1-crystallin promoter among vertebrate species. A stepwise deletion of the promoter sequence starting from 2800 bp indicated that the proximal 260 bp directly upstream of the transcription initiation site is sufficient for eliciting lens-specific expression, but the 150 bp promoter sequence is inactive despite it containing the XPL-1 and XPL-2 sequences, suggesting the presence of an additional and essential regulatory sequence located between ,150 and ,260 bp. Activity of the ,B1-crystallin promoter during lens regeneration from cornea was examined using transgenic tadpoles and found to have the same dependence on promoter regions as in embryonic lens development, indicating that gene regulation is largely shared by the two lens-generating processes. [source]

Molecular mechanisms and diagnosis of chromosome 22q11.2 rearrangements

DEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 1 2008
Beverly S. Emanuel
Abstract Several recurrent, constitutional genomic disorders are present on chromosome 22q. These include the translocations and deletions associated with DiGeorge and velocardiofacial syndrome and the translocations that give rise to the recurrent t(11;22) supernumerary der(22) syndrome (Emanuel syndrome). The rearrangement breakpoints on 22q cluster around the chromosome-specific segmental duplications of proximal 22q11, which are involved in the etiology of these disorders. While the deletions are the result of nonallelic homologous recombination (NAHR) between low copy repeats or segmental duplications within 22q11, the t(11;22) is the result of rearrangement between palindromic AT-rich repeats on 11q and 22q. Here we describe the mechanisms responsible for these recurrent rearrangements, discuss the recurrent deletion endpoints that are the result of NAHR between chromosome 22q specific low copy repeats as well as present current diagnostic approaches to deletion detection. © 2008 Wiley-Liss, Inc. Dev Disabil Res Rev 2008;14:11,18. [source]

Effects of activation of hedgehog signaling on patterning, growth, and differentiation in Xenopus froglet limb regeneration

DEVELOPMENTAL DYNAMICS, Issue 8 2009
Nayuta Yakushiji
Abstract Regenerating limbs of urodele amphibians and Xenopus tadpole are reconstructed along proximal,distal, anterior,posterior (AP), and dorsal,ventral axes. In contrast, a regenerated limb of the Xenopus froglet does not have digits, and only a simple cartilaginous structure referred to as a "spike" is formed. This suggests that repatterning along the AP axis is absent in the froglet blastema. Previous studies have shown that Shh and its target genes are not expressed in the froglet blastema. In this study, we activated Hedgehog signaling in the froglet blastema and found that target genes of Shh were inducible in the mesenchyme of limb blastema. Furthermore, we found that activation of the signaling had effects on blastema cell proliferation and chondrogenesis and resulted in the formation of multiple cartilaginous structures. These findings indicate that activation of signaling that is absent in the froglet blastema is effective for improvement of limb regeneration ability in the Xenopus froglet. Developmental Dynamics, 2009. © 2009 Wiley-Liss, Inc. [source]

Conditional gene inactivation reveals roles for Fgf10 and Fgfr2 in establishing a normal pattern of epithelial branching in the mouse lung

DEVELOPMENTAL DYNAMICS, Issue 8 2009
Lisa L. Abler
Abstract Fibroblast growth factor 10 (FGF10) signaling through FGF receptor 2 (FGFR2) is required for lung initiation. While studies indicate that Fgf10 and Fgfr2 are also important at later stages of lung development, their roles in early branching events remain unclear. We addressed this question through conditional inactivation of both genes in mouse subsequent to lung initiation. Inactivation of Fgf10 in lung mesenchyme resulted in smaller lobes with a reduced number of branches. Inactivation of Fgfr2 in lung epithelium resulted in disruption of lobes and small epithelial outgrowths that arose arbitrarily along the main bronchi. In both mutants, there was an increase in cell death. Also, the expression patterns of key signaling molecules implicated in branching morphogenesis were altered and a proximal lung marker was expanded distally. Our results indicate that both Fgf10 and Fgfr2 are required for a normal branching program and for proper proximal,distal patterning of the lung.Developmental Dynamics 238:1999,2013, 2009. © 2009 Wiley-Liss, Inc. [source]

Lower-extremity selective voluntary motor control in patients with spastic cerebral palsy: increased distal motor impairment

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 3 2010
EILEEN G FOWLER
Aim, Multiple impairments contribute to motor deficits in spastic cerebral palsy (CP). Selective voluntary motor control (SVMC), namely isolation of joint movement upon request, is important, but frequently overlooked. This study evaluated the proximal to distal distribution of SVMC impairment among lower extremity joints. Method, Using a recently developed tool, the Selective Control Assessment of the Lower Extremity (SCALE), we evaluated the SVMC of the hip, knee, ankle, subtalar joint, and toes in a cross-sectional, observational study of 47 participants with spastic, diplegic, hemiplegic, and quadriplegic CP (22 males, 25 females; mean age 11y 9mo, SD 4y 8mo; Gross Motor Function Classification System levels I,IV). Results, Statistically significant decreases in SCALE scores from hip to toes were found using the Page statistical test for trend (p<0.001). Statistically significant differences (p<0.05) were found between all joint pairs, except toes versus subtalar, toes versus ankle, and right ankle versus subtalar joints. Cross-tabulation of score frequencies for all pairs revealed that proximal joint scores were higher or equal to distal ones 81 to 100% of the time. Excluding toes versus subtalar joints, proximal scores exceeded distal ones 94 to 100% of the time. Interpretation, We confirmed increasing proximal to distal SVMC impairment, which may have implications for treatment and research. [source]

Activation of ADF/cofilin mediates attractive growth cone turning toward nerve growth factor and netrin-1

DEVELOPMENTAL NEUROBIOLOGY, Issue 8 2010
Bonnie M. Marsick
Abstract Proper neural circuitry requires that growth cones, motile tips of extending axons, respond to molecular guidance cues expressed in the developing organism. However, it is unclear how guidance cues modify the cytoskeleton to guide growth cone pathfinding. Here, we show acute treatment with two attractive guidance cues, nerve growth factor (NGF) and netrin-1, for embryonic dorsal root ganglion and temporal retinal neurons, respectively, results in increased growth cone membrane protrusion, actin polymerization, and filamentous actin (F-actin). ADF/cofilin (AC) family proteins facilitate F-actin dynamics, and we found the inactive phosphorylated form of AC is decreased in NGF- or netrin-1-treated growth cones. Directly increasing AC activity mimics addition of NGF or netrin-1 to increase growth cone protrusion and F-actin levels. Extracellular gradients of NGF, netrin-1, and a cell-permeable AC elicit attractive growth cone turning and increased F-actin barbed ends, F-actin accumulation, and active AC in growth cone regions proximal to the gradient source. Reducing AC activity blunts turning responses to NGF and netrin. Our results suggest that gradients of NGF and netrin-1 locally activate AC to promote actin polymerization and subsequent growth cone turning toward the side containing higher AC activity. © 2010 Wiley Periodicals, Inc. Develop Neurobiol 70: 565,588, 2010 [source]

Convergence of multisensory inputs in Xenopus tadpole tectum

DEVELOPMENTAL NEUROBIOLOGY, Issue 14 2009
Masaki Hiramoto
Abstract The integration of multisensory information takes place in the optic tectum where visual and auditory/mechanosensory inputs converge and regulate motor outputs. The circuits that integrate multisensory information are poorly understood. In an effort to identify the basic components of a multisensory integrative circuit, we determined the projections of the mechanosensory input from the periphery to the optic tectum and compared their distribution to the retinotectal inputs in Xenopus laevis tadpoles using dye-labeling methods. The peripheral ganglia of the lateral line system project to the ipsilateral hindbrain and the axons representing mechanosensory inputs along the anterior/posterior body axis are mapped along the ventrodorsal axis in the axon tract in the dorsal column of the hindbrain. Hindbrain neurons project axons to the contralateral optic tectum. The neurons from anterior and posterior hindbrain regions project axons to the dorsal and ventral tectum, respectively. While the retinotectal axons project to a superficial lamina in the tectal neuropil, the hindbrain axons project to a deep neuropil layer. Calcium imaging showed that multimodal inputs converge on tectal neurons. The layer-specific projections of the hindbrain and retinal axons suggest a functional segregation of sensory inputs to proximal and distal tectal cell dendrites, respectively. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2009 [source]

A succession of anesthetic endpoints in the Drosophila brain

DEVELOPMENTAL NEUROBIOLOGY, Issue 11 2006
Bruno van Swinderen
Abstract General anesthetics abolish behavioral responsiveness in all animals, and in humans this is accompanied by loss of consciousness. Whether similar target mechanisms and behavioral endpoints exist across species remains controversial, although model organisms have been successfully used to study mechanisms of anesthesia. In Drosophila, a number of key mutants have been characterized as hypersensitive or resistant to general anesthetics by behavioral assays. In order to investigate general anesthesia in the Drosophila brain, local field potential (LFP) recordings were made during incremental exposures to isoflurane in wild-type and mutant flies. As in higher animals, general anesthesia in flies was found to involve a succession of distinct endpoints. At low doses, isoflurane uncoupled brain activity from ongoing movement, followed by a sudden attenuation in neural correlates of perception. Average LFP activity in the brain was more gradually attenuated with higher doses, followed by loss of movement behavior. Among mutants, a strong correspondence was found between behavioral and LFP sensitivities, thereby suggesting that LFP phenotypes are proximal to the anesthetic's mechanism of action. Finally, genetic and pharmacological analysis revealed that anesthetic sensitivities in the fly brain are, like other arousal states, influenced by dopaminergic activity. These results suggest that volatile anesthetics such as isoflurane may target the same processes that sustain wakefulness and attention in the brain. LFP correlates of general anesthesia in Drosophila provide a powerful new approach to uncovering the nature of these processes. © 2006 Wiley Periodicals, Inc. J Neurobiol 66: 1195,1211, 2006 [source]

Ultrastructural changes in skeletal muscle of the tail of the lizard Hemidactylus mabouia immediately following autotomy

ACTA ZOOLOGICA, Issue 4 2010
Tomaz Henrique Araújo
Abstract Araújo, T.H., Faria, F.P., Katchburian, E. and Freymüller, E. (2009). Ultrastructural changes in skeletal muscle of the tail of the lizard Hemidactylus mabouia immediately following autotomy. ,Acta Zoologica (Stockholm) 91: 440,446. Although autotomy and subsequent regeneration of lizard tails has been extensively studied, there is little information available on ultrastructural changes that occur to the muscle fibers at the site of severance. Thus, in the present study, we examine the ultrastructure of the musculature of the remaining tail stump of the lizard Hemidactylus mabouia immediately after autotomy. Our results show that exposed portions of the skeletal muscle fibers of the stump that are unprotected by connective tissue bulge to produce large mushroom-like protrusions. These exposed portions show abnormal structure but suffer no leakage of cytoplasmic contents. Many small and large vesicular structures appeared between myofibrils in the interface at this disarranged region (distal) and the other portion of the fibers that remain unchanged (proximal). These vesicles coalesce, creating a gap that leads to the release of the mushroom-like protrusion. So, our results showed that after the macroscopic act of autotomy the muscular fibers release part of the sarcoplasm as if a second and microscopic set of autotomic events takes place immediately following the macroscopic act of autotomy. Presumably these changes pave the way for the formation of a blastema and the beginning of regeneration. [source]

Effect of pantoprazole in patients with chronic laryngitis and pharyngitis related to gastroesophageal reflux disease: clinical, proximal, and distal pH monitoring results

DISEASES OF THE ESOPHAGUS, Issue 4 2010
S. Karoui
SUMMARY Few studies had evaluated the results of proton pump inhibitors on distal and proximal pH recording using a dual-channel probe. The aim of this study was to determine the clinical and pH-metric effect of treatment with pantoprazole 80 mg for 8 weeks in patients with ear, nose, and throat (ENT) manifestations of gastroesophageal reflux disease associated with pathological proximal acid exposure. We conducted a prospective open study. Patients included had to have chronic pharyngitis or laryngitis, and a pathological gastroesophagopharyngeal reflux. All patients received treatment with pantoprazole 80 mg daily for 8 weeks. One week after the end treatment, patients had a second ENT examination and a 24-hour pH monitoring using dual-channel probe. We included 33 patients (11 men, 22 women). A pathological distal acid reflux was found in 30 patients (91%). After treatment, the improvement of ENT symptoms was found in 51.5% of patients. Normalization of 24-hour proximal esophageal pH monitoring was observed in 22 patients (66%). After treatment, the overall distal acid exposure, the number of distal reflux events, and the number of reflux during more than 5 minutes were significantly decreased (respectively: 19.4% vs 7.2% [P < 0.0001], 62.7 vs 28.4 [P < 0.0001], and 10.4 vs 3.9 [P < 0.0001] ). Similarly, in proximal level, the same parameters were significantly decreased after treatment (respectively: 6.8% vs 1.6% [P < 0.0001], 32.6 vs 8.1 [P < 0.0001], and 3.4 vs 0.6 [P= 0.005] ). Treatment with pantoprazole reduced the frequency and severity of gastroesophagopharyngeal acid reflux in patients with chronic pharyngitis and laryngitis. [source]

Diagnosis of eosinophilic esophagitis after fundoplication for ,refractory reflux': implications for preoperative evaluation

DISEASES OF THE ESOPHAGUS, Issue 3 2010
Evan S. Dellon
SUMMARY A small percentage of patients who carry the diagnosis of refractory gastroesophageal reflux disease (GERD) actually have eosinophilic esophagitis (EoE). The purpose of this study was to describe a series of patients who underwent fundoplication for presumed refractory GERD, but subsequently were found to have EoE. We performed a retrospective analysis of our EoE database. Patients diagnosed with EoE after Nissen were identified. Cases were defined according to recent consensus guidelines. Five patients underwent anti-reflux surgery for refractory GERD, but were subsequently diagnosed with EoE. None had esophageal biopsies prior to surgery, and in all subjects, symptoms persisted afterward, with no evidence of wrap failure. The diagnosis of EoE was typically delayed (range: 3,14 years), and when made, there were high levels of esophageal eosinophilia (range: 30,170 eos/hpf). A proportion of patients undergoing fundoplication for incomplete resolution of GERD symptoms will be undiagnosed cases of EoE. Given the rising prevalence of EoE, we recommend obtaining proximal and distal esophageal biopsies in such patients prior to performing anti-reflux surgery. [source]

Nonoperative treatment of four esophageal perforations with hemostatic clips

DISEASES OF THE ESOPHAGUS, Issue 5 2007
A. Fischer
SUMMARY., Spontaneous or iatrogenic esophageal perforations are despite advances of modern surgery and intensive care medicine still potentially life-threatening events with a considerable mortality rate. Recently, encouraging results on the sealing of esophageal perforations by placement of endoluminal prostheses were reported. However, if the perforation is very proximal (close to the larynx) or very distal (involving the cardia), the situation is to our experience unsuitable for stent therapy. In these special cases non-operative treatment is still possible by application of hemostatic metal clips. We present four cases unsuitable for stent therapy where the perforation was sealed by endoscopic clip application. All patients had an uneventful recovery. Non-operative treatment of esophageal perforations with hemostatic metal clips is feasible and safe in cases not treatable with self-expanding metal stents. [source]

Whole stomach with antro-pyloric nerve preservation as an esophageal substitute: an original technique

DISEASES OF THE ESOPHAGUS, Issue 2 2004
J.-M. Collard
SUMMARY., The paper describes an original technique of gastric tailoring in which the two-thirds of the lesser curvature proximal to the crow's foot are denuded flush with the gastric wall, leaving both nerves of Latarjet and the hepatic branches of the left vagus nerve intact. Maintenance of the vagal supply to the antro-pyloric segment in two patients resulted in the presence of peristaltic contractions sweeping over the antrum on simple observation of the antral wall at the end of the procedure and on both upper G-I series and intragastric manometry tracings 6 weeks postoperatively. Gastric exposure to bile on 24-h gastric bile monitoring was normal 6 weeks after the operation. Neither patient had any gastrointestinal symptoms with the exception of early sensations of postprandial fullness when overeating. [source]

Esophageal motility changes after endoscopic intravariceal sclerotherapy with absolute alcohol

DISEASES OF THE ESOPHAGUS, Issue 2 2000
Ghoshal
Endoscopic sclerotherapy (EST) leads to structural and motility changes in the esophagus; the former are thought to be commoner after EST with absolute alcohol (AA), which is a commonly used sclerosant in India as it is cheap and effective. There are no previous studies on changes in esophageal motility after EST with AA. Accordingly, we studied patients with portal hypertension before (n = 24) and after (n = 22) variceal obliteration by EST with AA using a water perfusion esophageal manometry system. Contraction amplitude in the distal esophagus was reduced in the post-EST group compared with the pre-EST group (63.4 ± 24.9 vs. 18.2 ± 14.3 mmHg, p < 0.01). Duration of esophageal contraction in both the proximal and distal esophagus became prolonged in the post-EST compared with the pre-EST group (3.3 ± 0.8 vs. 5.4 ± 2.6 and 4.3 ± 1.1 vs. 6.6 ± 2.3 s, p < 0.001 for both). Lower esophageal sphincter (LES) pressure was reduced in the post-EST compared with the pre-EST group, although the difference was not significant statistically. Abnormal contraction waveforms were more frequent in the post-EST group. One patient in the post-EST group had persistent dysphagia in the absence of endoscopically documented stricture at the time of manometric study. This study shows frequent occurrence of esophageal dysmotility after EST with AA; however, esophageal dysmotility after EST was infrequently associated with motor dysphagia. [source]

Appendicular skeleton in Bachia bicolor (Squamata: Gymnophthalmidae): osteology, limb reduction and postnatal skeletal ontogeny

ACTA ZOOLOGICA, Issue 1 2009
Adriana Jerez
Abstract The osteology of the appendicular skeleton and its postnatal development are described in Bachia bicolor, a serpentiform lizard with reduced limbs. The pectoral girdle is well developed and the forelimb consists of a humerus, ulna, radius, five carpal elements (ulnare, radiale, distal carpals 4,3, centrale), four metacarpals (II, III, IV, V) and phalanges (phalangeal formula X-2-2-2-2). In the hindlimb, the femur is small and slender, and articulates distally with a series of ossified amorphous and extremely reduced elements that correspond to a fibula, tibia and proximal and distal tarsals 4 and 3. The pelvic girdle consists of ischium, pubis and ilium, but its two halves are widely separated; the ilium is the least reduced element. We describe the ossification and development during postnatal skeletal ontogeny, especially of epiphyseal secondary centres, ossifications of carpal elements, apophyseal ossifications and sesamoids. Compared to other squamates, B. bicolor shows an overall reduction in limb size, an absence of skeletal elements, a fusion of carpal elements, an early differentiation of apophyseal centres, and a low number of sesamoids and apophyseal centres. These observations suggest that the reductions are produced by heterochronic changes during postnatal development and probably during embryonic development; therefore the appendicular skeleton exhibits a pattern of paedomorphic features. [source]

Ultrastructure of the spermatozoon of Apus apus (Linnaeus 1758), the common swift (Aves; Apodiformes; Apodidae), with phylogenetic implications

ACTA ZOOLOGICA, Issue 4 2005
Barrie G. M. Jamieson
Abstract The spermatozoon of Apus apus is typical of non-passerines in many respects. Features shared with palaeognaths and the Galloanserae are the conical acrosome, shorter than the nucleus; the presence of a proximal as well as distal centriole; the elongate midpiece with mitochondria grouped around an elongate distal centriole; and the presence of a fibrous or amorphous sheath around the principal piece of the axoneme. The perforatorium and endonuclear canal are lost in A. apus as in some other non-passerines. All non-passerines differ from palaeognaths in that the latter have a transversely ribbed fibrous sheath whereas in non-passerines it is amorphous, as in Apus, or absent. The absence of an annulus is an apomorphic but homoplastic feature of swift, psittaciform, gruiform and passerine spermatozoa. The long distal centriole, penetrating the entire midpiece, is a remarkably plesiomorphic feature of the swift spermatozoa, known elsewhere only in palaeognaths. The long centriole of Apus, if not a reversal, would be inconsistent with the former placement of the Apodiformes above the Psittaciformes from DNA,DNA hybridization. In contrast to passerines, in A. apus the microtubules in the spermatid are restricted to a transient single row encircling the cell. The form of the spermatozoon fully justifies the exclusion of swifts from the passerine family Hirundinidae. [source]