Peri

Distribution by Scientific Domains
Distribution within Medical Sciences


Selected Abstracts


Titelbild: Beton- und Stahlbetonbau 11/2009

BETON- UND STAHLBETONBAU, Issue 11 2009
Article first published online: 29 OCT 200
Im Rahmen der Anpassung an die neuen Reinigungsstandards gemäß europäischer Wasserrahmenrichtlinie, die bis 2015 umgesetzt werden müssen, entsteht zurzeit in Warschau die Großkläranlage Czajka. Mit einer Reinigungskapazität von ca. 450000 m3 pro Tag und einer Fläche von 600000 m2 wird Czajka die größte Kläranlage Polens und ist außerdem eine bedeutende Umweltschutzmaßnahme. Das Schalungs- und Gerüstkonzept zur Herstellung der insgesamt ca. 80000 m2 Wandflächen unterschiedlicher Größe und Form wurde von der Fa. PERI gemeinsam mit dem polnischen Baukonzern Warbud entwickelt. Es musste gleichzeitig hohe Anforderungen an die Arbeitssicherheit erfüllen und die termingerechte Fertigstellung der 120 Einzelbauwerke gewährleisten. (Foto: PERI) [source]


Titelbild: Beton- und Stahlbetonbau 10/2008

BETON- UND STAHLBETONBAU, Issue 10 2008
Article first published online: 6 OCT 200
Mit dem neuen Citytunnel Malmö soll die Eisenbahnverbindung zwischen Schweden und Dänemark noch schneller werden. Kernstücke des schwedischen Milliardenprojekts sind die 11 km lange Direktverbindung zwischen der Öresundbrücke und dem Zentralbahnhof Malmö und die neue unterirdische Bahnstation unmittelbar am bestehenden Bahnhof. Dabei entstehen auch zwei zusätzliche Bahnstationen in Innenstadtund Stadtrandlage, deren Fertigstellung für 2011 geplant ist. Für den Einfahrtsbereich im Süden und die Bahnhofserweiterung im Norden lieferte PERI eine Kombination aus baustellenspezifischer Schalwagenkonstruktion und mietfähigen Systemgeräten. (Foto: PERI) [source]


Imiquimod Treatment of Superficial and Nodular Basal Cell Carcinoma: 12-Week Open-Label Trial

DERMATOLOGIC SURGERY, Issue 3 2005
Ketty Peris MD
Background Imiquimod is an immune response modifier shown to be effective in basal cell carcinoma (BCC). Objective To evaluate the efficacy, tolerability, and response durability of imiquimod 5% cream in selected patients with superficial and/or nodular BCCs. Methods Seventy-five superficial and 19 nodular BCCs in 49 patients were treated with imiquimod once daily three times a week for up to 12 weeks. Results Of the 49 enrolled patients, 1 discontinued the study and 1 was lost to follow-up. After 12 weeks of treatment, a complete response occurred in 70 of 75 (93.3%) superficial BCCs and a partial response in 4 of 75 (5.3%) superficial BCCs. Ten of 19 (52.6%) nodular BCCs cleared after 12 weeks, whereas 7 (36.8%) showed partial remission. Adverse side effects were limited to local skin reactions. Recurrence was observed in 2 of 70 (2.9%) successfully treated superficial BCCs 6 and 8 months after treatment discontinuation. No recurrence was detected in 68 of 70 (97.1%) superficial BCCs and in 10 successfully treated nodular BCCs after 12 to 34 months of follow-up (mean 23 months). Conclusions In our patient population, treatment of superficial BCCs with topical imiquimod for 12 weeks produced an excellent clinical response overall, with complete remission maintained after a mean of 23 months. KETTY PERIS, MD, ELENA CAMPIONE, MD, TAMARA MICANTONIO, MD, GEORGIANA CLARE MARULLI, MD, MARIA CONCETTA FARGNOLI, MD, AND SERGIO CHIMENTI, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. [source]


Protein phosphatase 1, is required for murine lung growth and morphogenesis

DEVELOPMENTAL DYNAMICS, Issue 4 2004
Kadija-Kathy Hormi-Carver
Abstract Protein phosphatase 1 (PP1) plays important roles in cell cycle control and apoptosis, two processes that impinge on morphogenesis and differentiation. Following the precedent set by other molecules regulating the cell cycle and apoptosis, we hypothesized that PP1 may have context-specific roles in development. Therefore, we have studied the spatial and temporal expression of PP1, during murine lung development and determined the consequences of loss of PP1, function on branching morphogenesis. By using an immunohistochemical approach, we show here that PP1, was expressed throughout the epithelium and mesenchyme upon the emergence of the lung primordium on embryonic day 10, with immunostaining exclusively extranuclear. During the late pseudoglandular stage, PP1, was predominantly expressed in the distal lung epithelium, whereas the mesenchyme contained very little or no PP1, protein. Peri- and postnatally, PP1, immunostaining was mostly nuclear in apparently differentiated cells, as judged by colocalization with well-known markers for lung differentiation. Exposure of fetal lung explants to antisense oligodeoxynucleotides against PP1,, resulted in decreased overall size of the cultured lung, a defect in forming new airways, lack of expression of surfactant protein C, and histologic signs of poor differentiation. These data suggest that PP1, is required for branching morphogenesis and differentiation. Developmental Dynamics 229:791,801, 2004. © 2004 Wiley-Liss, Inc. [source]


A simple robust numerical integration algorithm for a power-law visco-plastic model under both high and low rate-sensitivity

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 1 2004
E. A. de Souza Neto
Abstract This note describes a simple and extremely robust algorithm for numerical integration of the power-law-type elasto-viscoplastic constitutive model discussed by Peri, (Int. J. Num. Meth. Eng. 1993; 36: 1365,1393). As the rate-independent limit is approached with increasing exponents, the evolution equations of power-law-type models are known to become stiff. Under such conditions, the solution of the implicitly discretized viscoplastic evolution equation cannot be easily obtained by standard root-finding algorithms. Here, a procedure which proves to be remarkably robust under stiff conditions is obtained by means of a simple logarithmic mapping of the basic backward Euler time-discrete equation for the incremental plastic multiplier. The logarithm-transformed equation is solved by the standard Newton,Raphson scheme combined with a simple bisection procedure which ensures that the iterative guesses for the equation unknown (the incremental equivalent plastic strain) remain within the domain where the transformed equation makes sense. The resulting implementation can handle small and large (up to order 106) power-law exponents equally. This allows its effective use under any situation of practical interest, ranging from high rate-sensitivity to virtually rate-independent conditions. The robustness of the proposed scheme is demonstrated by numerical examples. Copyright © 2003 John Wiley & Sons, Ltd. [source]


Laparoscopic management of urachal remnants in adulthood

INTERNATIONAL JOURNAL OF UROLOGY, Issue 12 2006
TAKATSUGU OKEGAWA
Background: The aim of this study was to investigate the outcome of laparoscopic excision of urachal remnants (LUR), and to compare the outcome with that of the traditional open excision of urachal remnants (OUR). Methods: Between February 2001 and December 2005, six patients with a mean age of 23.8 years who had a symptomatic urachal sinus underwent radical LUR. Using 12 mm and 5 mm ports, the caudal stump of the urachus was ligated with an absorbable clip and divided. The peritoneal and preperitoneal tissue between the medial umbilical ligaments was dissected free of the transversalis fascia. Dissection was carried out along the preperitoneal plane toward the umbilicus. The cephalic side of the lesion was ligated at the umbilicus with an endo-loop and divided. In addition, four patients who underwent a traditional OUR were included. Peri- and postoperative records were reviewed to assess morbidity, recovery, and outcome. Results: The operative duration was not significantly shorter for the LUR group than the OUR group, but there was generally a reduction in blood loss (mean 16.5 vs 68.3 mL), an earlier resumption of eating (mean 1.3 vs 2.5 days), and a shorter hospital stay (mean 5.3 vs 10.5 days). There were no intraoperative complications in either the LUR or the OUR group. Mean follow up was 5 (range 4,12) months. There were no postoperative complications. Conclusions: The results suggest that LUR can be safely and satisfactorily performed in adulthood. [source]


Fluid evolution and thermal structure in the rapidly exhuming gneiss complex of Namche Barwa,Gyala Peri, eastern Himalayan syntaxis

JOURNAL OF METAMORPHIC GEOLOGY, Issue 9 2005
D. CRAW
Abstract High-grade gneisses (amphibolite,granulite facies) of the Namche Barwa and Gyala Peri massifs, in the eastern Himalayan syntaxis, have been unroofed from metamorphic depths in the late Tertiary,Recent. Rapid exhumation (2,5 mm year,1) has resulted in a pronounced shallow conductive thermal anomaly beneath the massifs and the intervening Tsangpo gorge. The position of the 300 °C isotherm has been estimated from fluid inclusions using CO2,H2O immiscibility phase equilibria to be between 2.5 and 6.2 km depth below surface. Hence, the near-surface average thermal gradient exceeds 50 °C km,1 beneath valleys, although the thermal gradient is relatively lower beneath the high mountains. The original metamorphic fluid in the gneisses was >90% CO2. This fluid was displaced by incursion of brines from overlying marine sedimentary rocks that have since been largely removed by erosion. Brines can exceed 60 wt% dissolved salts, and include Ca, Na, K and Fe chlorides. These brines were remobilized during the earliest stages of uplift at >500 °C. During exhumation, incursion of abundant topography-driven surface waters resulted in widespread fracture-controlled hydrothermal activity and brine dilution down to the brittle,ductile transition. Boiling water was particularly common at shallow levels (<2.5 km) beneath the Yarlung Tsangpo valley, and numerous hot springs occur at the surface in this valley. Dry steam is not a major feature of the hydrothermal system in the eastern syntaxis (in contrast to the western syntaxis at Nanga Parbat), but some dry steam fluids may have developed locally. [source]


Laparoscopic radical prostatectomy: early safety and efficacy

ANZ JOURNAL OF SURGERY, Issue 12 2004
Liam C. Wilson
Background: To evaluate the initial results of laparoscopic radical prostatectomy at this institution. Methods: Between January 2000 and September 2003, 30 patients underwent laparoscopic radical prostatectomy. Peri- and postoperative data were accumulated prospectively and maintained in a database. All patients have a minimum of 6 month follow up. Results: There were no conversions to open surgery, and there were no re-operations. Mean operating time was 328 (195,490) min. There was one intraoperative rectal injury which was repaired laparoscopically. Three patients (10%) required blood transfusion. Postoperatively, there were two cases of respiratory depression, one case of haemoptysis and one upper gastrointestinal bleed. Two anastomotic leaks were successfully treated conservatively, one of which was the only readmission to hospital. There was one case of clot retention requiring manual irrigation of the bladder. Mean hospital stay was 2.75 (1,10) days, with six of the last 10 patients being discharged on the first postoperative day. Continence rates at 6 months are 83%. Positive surgical margins occurred in seven patients (23%). At 12 months of follow up, one patient (4.5%) has had biochemical recurrence. Conclusions: Our initial results are comparable to, or better than, the initial series in high volume centres. The procedure is feasible in appropriately selected cases in the Australasian environment. [source]


Validation of Serbian version of the disease-specific myasthenia gravis questionnaire

ACTA NEUROLOGICA SCANDINAVICA, Issue 2 2010
I. Basta
Basta I, Pekmezovi, T, Padua L, Stojanovi, V, Stevi, Z, Nikoli, A, Peri, S, Lavrni, D. Validation of Serbian version of the disease-specific myasthenia gravis questionnaire. Acta Neurol Scand: 2010: 122: 110,114. © 2009 The Authors Journal compilation © 2009 Blackwell Munksgaard. Aim,,, The aim of this study was to validate translated and cross-cultural adapted Italian version of myasthenia gravis-specific questionnaire (MGQ) in Serbian MG patients. Materials and Methods,,, The questionnaire was validated in 140 consecutive MG patients from Belgrade. In each patient association between the total MGQ score and form and severity of the disease was determined. Also, correlation between regional domain scores of MGQ and main clinical findings according to Besinger's clinical score was analyzed. Results,,, Patients' participation in the assessment was satisfactory with excellent internal consistency and reproducibility. Total MGQ score, as well as domain scores, correlated with highly significant inverse relationship with the disease severity and clinical status of patients at the moment of completing the questionnaire. Furthermore, the bulbar domain of the questionnaire appeared more specific and sensitive than clinical history and examination. Conclusion,,, We concluded that the Serbian version of the MGQ may be useful as a measure of clinical outcome in patients with MG. [source]


Peri and Regioselective Synthesis of New Heterocyclic Compounds from 1,5-Benzodiazepines.

CHEMINFORM, Issue 23 2003
S. Elhazazi
Abstract For Abstract see ChemInform Abstract in Full Text. [source]


ChemInform Abstract: Highly Peri-, Regio- and Diastereoselective 1,3-Dipolar Cycloaddition of Mesitonitrile Oxide to 1,7-Dimethyl-2,3-dihydro-1H-1,4-diazepines: Unexpected One-Step Formation of a New Triheterocyclic Framework.

CHEMINFORM, Issue 29 2002
Abdesselam Baouid
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 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]


Autism spectrum disorders in children with active epilepsy and learning disability: comorbidity, pre- and perinatal background, and seizure characteristics

DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 11 2003
Suzanne Steffenburg MD PhD
The aim of this study was to examine the comorbidity pattern, seizure characteristics, and aetiology in a representative group of children with a combination of autism spectrum disorder (ASD), active epilepsy, and learning disability. Ninety children (47 males, 43 females; mean age 11 years 2 months, range 8 to 16 years at the time of psychiatric examination) with active epilepsy and learning disability, identified in a population-based study in Göteborg, Sweden, were subdivided into those with and those without ASD and compared with respect to aetiology, additional neuroimpairments, and seizure characteristics. In addition, the cohorts were examined for trends of prevalence over a period of time. Results indicated that established aetiology was much more often present in the prenatal period than in the peri- or postnatal periods in the ASD group. Cerebral palsy and visual impairment were under-represented in the ASD group. Partial seizures tended to be more common and generalized seizures less common in the ASD group compared with the non-ASD group. Seizure onset was later in the ASD group. Many of the significant differences were accounted for by a large group of psychiatrically unclassifiable participants in the non-ASD group. There was no trend towards an increase of affected children over the 12-year period. There was no increase in the prevalence of active epilepsy and learning disability nor in the rate of autism with active epilepsy and learning disability in children born between 1981 and 1986 compared with those born from 1976 to 1980, indicating no statistical association with the general measles-mumps-rubella vaccination introduced in the early 1980s. [source]


Early brain lesions and face-processing development

DEVELOPMENTAL PSYCHOBIOLOGY, Issue 3 2005
Scania de Schonen
Abstract Studies of functional plasticity after pre- or perinatal brain damage can tell us whether the neural substrate normally involved in the development of a given ability is specific and, if so, when it becomes functionally specified and unique. Development of face processing was investigated in 5- to 17-year-old children who had a unilateral brain injury in the pre-, peri-, or postnatal period. In Studies 1 and 2, patients with a posterior injury involving the temporal regions exhibited a face-processing deficit that was independent of their age at test time. Even though differences were observed between the two hemispheres in face processing during infancy as well as in adults in cases of normal development, no clear differences between right and left injury were observed here in face-processing deficit. Poor postlesional face-processing plasticity seems to contrast with results of several studies on speech development after early unilateral injury. If the difference in the time window for postlesional plasticity between these two areas of competency is confirmed, it would suggest that the two kinds of abilities rely on neural cells which are sensitive to different plasticity factors. © 2005 Wiley Periodicals, Inc. Dev Psychobiol 46: 184,208, 2005. [source]


ENDOSCOPIC SUBMUCOSAL DISSECTION FOR ESOPHAGEAL SQUAMOUS CELL NEOPLASMS

DIGESTIVE ENDOSCOPY, Issue 2 2009
Mitsuhiro Fujishiro
Endoscopic submucosal dissection (ESD) has gradually gained acceptance as one of the standard treatments for early esophageal cancer, as well as for early gastric cancer in Japan, but standardization of the knowledge is still incomplete. The final goal to perform ESD is not to resect the lesion in an en bloc fashion, but to save the patient from esophageal cancer-related death. Thus, the indications should be considered based on the entire patient, not just the target lesion itself, and pre-, peri- and postoperative management of the patient is also very important, as well as technical aspects of ESD. In terms of the techniques of ESD, owing to refinement of the procedural strategy, invention of the devices, and the learning curve, acceptable safety and favorable middle-term efficacy have been obtained. We believe that ESD will become a standard treatment for early esophageal cancer not only in Japan but also worldwide in the near future. [source]


Diffusion-based magnetic resonance imaging and tractography in epilepsy

EPILEPSIA, Issue 2 2008
Mahinda Yogarajah
Summary Diffusion-based imaging is an advanced MRI technique that is sensitive to the movement of water molecules, providing additional information on the micro-structural arrangement of tissue. Qualitative and quantitative analysis of peri, post and interictal diffusion images can aid the localization of seizure foci. Diffusion tensor tractography is an extension of diffusion-based imaging, and can provide additional information about white matter pathways. Both techniques are able to increase understanding of the effects of epilepsy on the structural organization of the brain, and can be used to optimize presurgical planning of patients with epilepsy. This review focuses on the basis, applications, limitations, and future directions of diffusion imaging in epilepsy. Literature search strategy: We searched Pubmed using the terms "diffusion MRI or diffusion tensor MRI or tractography and epilepsy." [source]


1,8-Bis(dialkylamino)-4,5-dinitronaphthalenes and 4,5-Bis(dimethylamino)naphthalene-1,8-dicarbaldehyde as "Push,Pull" Proton Sponges: When and Why Formyl Groups Become Stronger ,-Electron Acceptors than Nitro Groups

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 8 2009
Valery A. Ozeryanskii
Abstract Single-crystal X-ray studies of four representatives of "push,pull" proton sponges, namely 1,8-bis(dimethylamino)-, 1,8-bis(diethylamino)-, 1,8-bis(dipropylamino)-4,5-dinitronaphthalenes and 4,5-bis(dimethylamino)naphthalene-1,8-dicarbaldehyde have been performed at low and ambient temperatures. The most interesting and unexpected result is that the formyl groups in the peri -dialdehyde display stronger ,-acceptor effects than the nitro groups. This phenomenon is ascribed to smaller steric demands of the CHO groups, their lower electrostatic repulsion, and specific packing forces. The naphthalene cores of all but one of the molecules are markedly twisted (21,26°) while that of the diethylamino derivative is not (<5°), providing different and somewhat unpredictable ways of resonance stabilization and steric relaxation. The through-conjugation in the above compounds is also discussed for gas and solution phases on the basis of theoretical calculations, UV/Vis and 1H NMR spectra.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source]


The Synthesis of the Dimethyl Ester of Quino[4,4a,5,6- efg]-Annulated 7-Demethyl-8-deethylmesoporphyrin and Three of Its Isomers with Unprecedented peri -Condensed Quinoline Porphyrin Structures.

EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 19 2004
Molecules with Outstanding Properties as Sensitizers for Photodynamic Therapy in the Far-Red Region of the Visible Spectrum
Abstract The mesoporphyrin dimethyl ester nickel complex has been formylated via the Vilsmeier method. The four possible mono meso-formyl derivatives were isolated and characterized. Wadsworth,Emmons coupling with the anion of (diethylphosphono)acetonitrile converted these aldehydes into the four novel meso acrylonitriles. Brief treatment of these acrylonitrile systems in hot trichloroacetic acid resulted in the formation of four achiral porphyrin derivatives with unprecedented nickel complexes of quino-fused porphyrins. Subsequent removal of the nickel gave four quino-porphyrin free bases: quino[4,4a,5,6- efg]-annulated 7-demethyl-8-deethylmesoporphyrin dimethyl ester 6a, 2,-(methoxycarbonyl)quino[4,4a,5,6- jkl]-annulated 12-demethyl-13-de[2,-(methoxycarbonyl)ethyl]mesoporphyrin dimethyl ester 6b, 2,-(methoxycarbonyl)quino[4,4a,5,6- qrs]-annulated 18-demethyl-17-de(2,-methoxycarbonylethyl)mesoporphyrin dimethyl ester 6c and quino[4,5,6,7- abt]-annulated 2-demethyl-3-deethylmesoporphyrin dimethyl ester 6d. The structures of these systems were unambiguously determined via mass spectroscopy and a plethora of NMR techniques. In the same way, etioporphyrin and octaethylporphyrin were converted into the corresponding peri -condensed quinoporphyrins as products, which shows that the formation of novel pericondensed quino-porphyrins is a general reaction in the porphyrin series and will have a wide scope in this field. Also, a plausible reaction mechanism for the formation of the quinoporphyrin systems was derived. As a first test for the use of these systems as sensitizers in far-red phototherapy, the quantum yield of singlet oxygen generation by 6a in toluene was studied. This quantum yield is 0.77, which is even higher than the singlet oxygen generation by sensitized meso-tetraphenylporphyrin. Secondly, when Chinese Hamster ovary (CHO) cells were incubated in medium which contained up to 15 ,g/ml of 6a, the survival rate of the cells in the dark is complete within experimental error, showing that under these conditions, 6a is not toxic to CHO cells. When CHO cells incubated in medium containing 6a in concentrations of 1 ,g/ml and higher were treated with white light of intensity 30 mW/cm2 for 15 minutes, complete cell death was observed. Based on these facts, we expect that all four achiral systems will show very promising properties to form the basis of a photodynamic therapy in far-red light. The fact that these systems are achiral is an additional bonus for medical applications. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source]


Hair growth inhibition by psychoemotional stress: a mouse model for neural mechanisms in hair growth control

EXPERIMENTAL DERMATOLOGY, Issue 1 2006
Eva M. J. Peters
Abstract:, Stress has long been discussed controversially as a cause of hair loss. However, solid proof of stress-induced hair growth inhibition had long been missing. If psychoemotional stress can affect hair growth, this must be mediated via definable neurorendocrine and/or neuroimmunological signaling pathways. Revisiting and up-dating relevant background data on neural mechanisms of hair growth control, we sketch essentials of hair follicle (HF) neurobiology and discuss the modulation of murine hair growth by neuropeptides, neurotransmitters, neurotrophins, and mast cells. Exploiting an established mouse model for stress, we summarize recent evidence that sonic stress triggers a cascade of molecular events including plasticity of the peptidergic peri- and interfollicular innervation and neuroimmune crosstalk. Substance P (SP) and NGF (nerve growth factor) are recruited as key mediators of stress-induced hair growth-inhibitory effects. These effects include perifollicular neurogenic inflammation, HF keratinocyte apoptosis, inhibition of proliferation within the HF epithelium, and premature HF regression (catagen induction). Intriguingly, most of these effects can be abrogated by treatment of stressed mice with SP-receptor neurokinin-1 receptor (NK-1) antagonists or NGF-neutralizing antibodies , as well as, surprisingly, by topical minoxidil. Thus there is now solid in vivo -evidence for the existence of a defined brain- HF axis. This axis can be utilized by psychoemotional and other stressors to prematurely terminate hair growth. Stress-induced hair growth inhibition can therefore serve as a highly instructive model for exploring the brain-skin connection and provides a unique experimental model for dissecting general principles of skin neuroendocrinology and neuroimmunology well beyond the HF. [source]


Solution Processable Fluorenyl Hexa- peri -hexabenzocoronenes in Organic Field-Effect Transistors and Solar Cells

ADVANCED FUNCTIONAL MATERIALS, Issue 6 2010
Wallace W. H. Wong
Abstract The organization of organic semiconductor molecules in the active layer of organic electronic devices has important consequences to overall device performance. This is due to the fact that molecular organization directly affects charge carrier mobility of the material. Organic field-effect transistor (OFET) performance is driven by high charge carrier mobility while bulk heterojunction (BHJ) solar cells require balanced hole and electron transport. By investigating the properties and device performance of three structural variations of the fluorenyl hexa- peri -hexabenzocoronene (FHBC) material, the importance of molecular organization to device performance was highlighted. It is clear from 1H NMR and 2D wide-angle X-ray scattering (2D WAXS) experiments that the sterically demanding 9,9-dioctylfluorene groups are preventing ,,, intermolecular contact in the hexakis-substituted FHBC 4. For bis-substituted FHBC compounds 5 and 6, ,,, intermolecular contact was observed in solution and hexagonal columnar ordering was observed in solid state. Furthermore, in atomic force microscopy (AFM) experiments, nanoscale phase separation was observed in thin films of FHBC and [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) blends. The differences in molecular and bulk structural features were found to correlate with OFET and BHJ solar cell performance. Poor OFET and BHJ solar cells devices were obtained for FHBC compound 4 while compounds 5 and 6 gave excellent devices. In particular, the field-effect mobility of FHBC 6, deposited by spin-casting, reached 2.8,×,10,3,cm2 V,1 s and a power conversion efficiency of 1.5% was recorded for the BHJ solar cell containing FHBC 6 and PC61BM. [source]


Self-Assembly of a Donor-Acceptor Dyad Across Multiple Length Scales: Functional Architectures for Organic Electronics

ADVANCED FUNCTIONAL MATERIALS, Issue 15 2009
Jeffrey M. Mativetsky
Abstract Molecular dyads based on polycyclic electron donor (D) and electron acceptor (A) units represent suitable building blocks for forming highly ordered, solution-processable, nanosegregated D-A domains for potential use in (opto)electronic applications. A new dyad, based on alkyl substituted hexa- peri -hexabenzocoronene (HBC) and perylene monoimide (PMI) separated by an ethinylene linker, is shown to have a high tendency to self-assemble into ordered supramolecular arrangements at multiple length scales: macroscopic extruded filaments display long-range crystalline order, nanofiber networks are produced by simple spin-coating, and monolayers with a lamellar packing are formed by physisorption at the solution-HOPG interface. Moreover, highly uniform mesoscopic ribbons bearing atomically flat facets and steps with single-molecule heights self-assemble upon solvent-vapor annealing. Electrical measurements of HBC-PMI films and mesoscopic ribbons in a transistor configuration exhibit ambipolar transport with well balanced p- and n-type mobilities. Owing to the increased level of order at the supramolecular level, devices based on ribbons show mobility increases of more than one order of magnitude. [source]


Carbon Nanotube/Hexa- peri -hexabenzocoronene Bilayers for Discrimination Between Nonpolar Volatile Organic Compounds of Cancer and Humid Atmospheres

ADVANCED MATERIALS, Issue 38 2010
Yael Zilberman
Cancer detection: The development of a cost-effective, portable and non-invasive diagnostic tool for detecting cancer from exhaled breath requires sensors that discriminate well between polar and nonpolar volatile organic compounds in highly humid atmospheres. Here we show that a chemiresistive bilayer comprised of a dense cap layer of discotic hexa-dodecyl-hexa-peri-hexabenzocoronene derivatives (hereby, HBC-C12) and a random network of carbon nanotubes (RN-CNT) as underlayer layer could fulfill these requirements. [source]


A Glass Hook Allows Fishing of Hexa- peri -hexabenzocoronene Graphitic Nanotubes: Fabrication of a Macroscopic Fiber with Anisotropic Electrical Conduction,

ADVANCED MATERIALS, Issue 10 2006
Y. Yamamoto
Fishing of graphitic nanotubes with a macroscopic glass hook: A ,30,mm long fiber (see figure and cover) is readily processed from a suspension of self-assembled nanotubes with one-handed helical chirality, formed from the (R)- or (S)-enantiomer of chiral amphiphile 2. The majority of the nanotubes in the fiber are unidirectionally oriented along the fiber axis. Upon doping with I2, the fiber displays an anisotropic electrical conduction along the fiber axis more than an order of magnitude greater than that across the fiber axis. [source]


Prophylactic steroids for paediatric open-heart surgery: a systematic review

INTERNATIONAL JOURNAL OF EVIDENCE BASED HEALTHCARE, Issue 4 2008
Suzi Robertson-Malt BHSc PhD
Background, The immune response to cardiopulmonary bypass in infants and children can lead to a series of post-operative morbidities and mortality, that is, hemodynamic instability, increased infection and tachyarrhythmias. Administration of prophylactic doses of corticosteroids is sometimes used to try and ameliorate this pro-inflammatory response. However, the clinical benefits and harms of this type of intervention in the paediatric patient remain unclear. Objectives, To systematically review the beneficial and harmful effects of the prophylactic administration of corticosteroids, compared with placebo, in paediatric open-heart surgery. Search strategy, The trials registry of the Cochrane Heart Group, the Cochrane Central Register of Controlled Trials in The Cochrane Library (Issue 4, 2006), MEDLINE (1966 to January 2007), EMBASE (1980 to January 2007) were searched. An additional hand-search of the EMRO database for Arabic literature was performed. Grey literature was searched, and experts in the field were contacted for any unpublished material. No language restrictions were applied. Selection criteria, All randomised and quasi-randomised controlled trials of open-heart surgery in the paediatric population that received corticosteroids pre-, peri- or post-operatively, with reported clinical outcomes in terms of morbidity and mortality. Data collection and analysis, Eligible studies were abstracted and evaluated by two independent reviewers. All meta-analyses were completed using RevMan4.2.8. Weighted mean difference (WMD) was the primary summary statistic with data pooled using a random-effects model. Main results, All cause mortality could not be assessed as the data reports were incomplete. There was weak evidence in favour of prophylactic corticosteroid administration for reducing intensive care unit stay, peak core temperature and duration of ventilation (WMD (95% confidence intervals) ,0.50 h (,1.41 to 0.41); ,0.20°C (,1.16 to 0.77) and ,0.63 h (,4.02 to 2.75) respectively). [source]


Peutz,Jeghers syndrome in a 14-year-old boy: case report and review of the literature

INTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 3 2005
C. M. PEREIRA
Summary., Peutz,Jeghers syndrome (PSJ) is a relatively rare but well-recognized condition, with a prevalence of approximately one in 120 000 births in the USA. It is generally inherited as an autosomal dominant trait, although 35% of cases are new mutations. This disorder is characterized by melanocytic macules on the hands, feet, peri,oral skin and oral mucosa, and multiple gastrointestinal hamartomatous polyps. People with PSJ have an increased risk for developing a variety of malignant tumours. The aim of the present study was to report one case of PSJ in a 14-year-old boy with mucocutaneous pigmentation associated with duodenal hamartomatous polyps. [source]


Expanding the Suzuki,Heck-Type Coupling Cascade: A New Indeno[1,2,3]-Annelation of Polycyclic Aromatic Hydrocarbons

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 7-8 2009
Jennifer
Abstract Fluoranthene derivatives can be constructed in a single operation by a palladium-catalyzed cascade reaction sequence, starting from a peri -dichloronaphthalene derivative and various arylboronic acids. [source]


Smoking May Impair the Bone Protective Effects of Nutritional Calcium: A Population-Based Approach,

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 6 2003
Joonas Sirola PhD
Abstract Postmenopausal women were randomly selected to investigate the effects of smoking on prevention of bone loss with nutritional calcium. DXA was performed twice, and smoking and calcium intake habits were inquired through the mail in 954 women. Smoking dampened the bone protective effects of nutritional calcium. This may reflect the pathophysiology underlying smoking-induced bone loss postmenopause. This study evaluated the effect of smoking on the bone protective properties of nutritional calcium. Of the random sample of 954 peri- and postmenopausal women selected from the Osteoporosis Risk Factor and Prevention (OSTPRE) study cohort (n = 13,100) in Kuopio, Finland, 182 had smoked at some time (ever smokers) and 772 had never smoked. Women were divided in tertiles according to self-reported dairy nutritional calcium intake (mg/day): <648 (1st), 648-927 (2nd), >927 (3rd). Bone mineral density at lumbar spine (LS) and femoral neck (FN) was measured with DXA at baseline in 1989-1991 and at the 5-year follow-up in 1994-1997. In a linear regression model, nutritional calcium intake did not predict annual bone loss in smokers. These results were similar in the subanalysis on 71 current smokers (at both baseline and 5-year measurements) and on 85 past smokers. In never smokers, a statistically significant linear trend was observed between calcium intake and annual bone loss at LS, but at FN only after adjustment for age, weight, hormone replacement therapy (HRT), and other covariates. In analysis of covariance (ANCOVA), no differences in bone loss rate were observed between calcium intake tertiles among smokers. In nonsmokers, the annual bone loss rate was lower in the second (,0.41%) and the third (,0.35%) tertile compared with the first tertile (,0.61%) at LS (p < 0.05) and lower in the third tertile (,0.55%) than in first tertile (,0.72%) at FN after adjustment for age, weight, HRT, and other covariates (p < 0.05). When smokers were added to the nonsmoker group, the differences in bone loss rate between calcium intake tertiles disappeared. In addition, in ANCOVA, the term of interaction between smoking and calcium intake was statistically significant at LS only. In conclusion, smoking seems to impair the bone protective effects of nutritional calcium in postmenopausal women, more clearly in LS than FN. [source]


Risk of hormone replacement therapy in stroke patients

JOURNAL OF CLINICAL PHARMACY & THERAPEUTICS, Issue 4 2000
Damczyk BSc
Hormone replacement therapy (HRT) (oestrogen with or without progestin) is often initiated with the onset of menopause to decrease symptoms of oestrogen deficiency, such as vasomotor instability (hot flashes) and urogenital effects ( 1,3). HRT can also prevent long-term consequences of oestrogen deficiency, such as osteoporosis and cardiovascular disease ( 1,3). The decision to start HRT in peri- and postmenopausal women is complicated by concerns of increased risk for thromboembolic events, uterine cancer and breast cancer ( 2,4). Thromboembolic stroke is a particular concern due to its association with the use of oral contraceptives with high oestrogen content ( 3, 4). However, for older women it has been suggested that HRT use decreases or has no effect on stroke risk ( 5,9). Should these findings apply to a women with a history of thromboembolism, in this case ischemic stroke? [source]


Endovascular Abdominal Aortic Aneurysm Repair by Interventional Cardiologists,A Community-Based Experience

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 5 2010
ABHIJEET BASOOR M.D.
Introduction:,Endovascular repair of abdominal aortic aneurysm (AAA) is a relatively recent technology. In comparison to the conventional open surgical treatment for AAA, endovascular AAA repair (EVAR) combines a less-invasive approach with lower morbidity and mortality. There have been few studies regarding the performance of this procedure in a community-based setting. We report our experience of EVAR performed primarily by interventional cardiologists in a community hospital. Methods:,In our community hospital setting, between September 2005 and November 2007, we included all patients who underwent EVAR by interventional cardiologists, with available on-site vascular surgical support. Clinical and serial computed angiographic imaging outcomes were followed by a retrospective chart review. Data collection tools included demographic and clinical characteristics, anatomical aneurysm features, length of stay, peri- and postprocedural complications, and mortality. Results:,A total of 71 consecutive patients had EVAR attempted. The endovascular stent placement was successful in 67 (93%) patients. Thirty-day mortality in this study was 1 of 71 (1.4%). All four procedural failures and the single periprocedural mortality occurred in women. Mean follow-up was 12 months. There were a total of six mortalities and among these four were women (P , 0.001); however, multivariate analysis revealed loss of significant difference in mortality (P = 0.16). Major complications following EVAR were noted in 10 of 71 (14%) patients. Conclusion:,EVAR can be successfully performed by experienced interventional cardiologists with vascular surgical support in a community-based setting. In our experience, there is acceptable rate of complications and mortality in a carefully selected patient population. (J Interven Cardiol 2010;23:485,490) [source]


Low-temperature bitumen stiffness and viscous paraffinic nano- and micro-domains by cryogenic AFM and PDM

JOURNAL OF MICROSCOPY, Issue 3 2007
J-F. MASSON
Summary In an effort to better understand the structure and behaviour of bitumen in low temperature, we describe the first use of cryogenic atomic force microscopy and phase detection microscopy to characterize bitumen nano- and micro-structures. The results were interpreted in light of glass transition temperatures (Tgs) for bitumen fractions. The domains visible by microscopy, the catana, peri and para phases, were attributed to domains rich in asphaltenes, naphthene and polar aromatics, and saturates, respectively. Between ,10°C and ,30°C, atomic force microscopy images revealed topographic features not visible in atomic force microscopy images acquired at room temperature. According to phase detection microscopy and Tgs, the features were assigned to viscous unfrozen saturates. Upon cooling to ,72°C, unfrozen domains of 20,400 nm were observed. These domains were found in the paraphase rich in saturates and in the periphase rich in naphthene aromatics and polar aromatics. The findings indicate that new viscous domains form upon cooling to low temperatures owing to phase segregation, and that some bitumens are never entirely rigid in low temperatures. [source]


Safety of Trans Vaginal Mesh procedure: Retrospective study of 684 patients

JOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 4 2008
Fréderic Caquant
Abstract Aim:, To study peri-surgical complications after cure of genital prolapse by vaginal route using interposition of synthetic prostheses Gynemesh Prolene Soft (Gynecare) following the Trans Vaginal Mesh (TVM) technique. Methods:, The present retrospective multicentered study comprised 684 patients who underwent surgery at seven French centers between October 2002 and December 2004. All patients had a genital prolapse ,3 (C3/H3/E3/R3) according to International continence society (ICS) classification. According to each case, prosthetic interposition was total, or anterior only or posterior only. Patients were systematically seen 6 weeks, 3 months and 6 months after surgery. Multivaried statistical analysis followed a model of logistic regression applied to each post-surgical complication. Results:, The mean age of patients was 63.5 years (30,94). The mean follow-up period was 3.6 months. 84.3% of patients were post-menopause, 24.3% had hysterectomy, 16.7% previous cure of prolapse, and 11.1% cure of stress urinary incontinence (SUI). During the procedure, hysterectomy was combined in 50.3% of cases, cervix amputation in 1.5%, and cure of SUI in 40.9%. 15.8% were treated for a cystocele only. 14.8% had only a rectocele +/, elytrocele and 69.4% had a prolapse touching both compartments, anterior and posterior. In peri-surgical complications, (2%) were five bladder wounds (0.7%), one rectal wound (0.15%) and seven hemorrhages greater that 200 mL (1%). Among early post-surgical complications (during the first month after surgery) (2.8%) were two pelvic abscesses (0.29%), 13 pelvic hematomas (1.9%), one pelvic cellulitis (0.15%), two vesicovaginal fistulas and one rectovaginal fistula (0.15%). Among late post-surgical complications (33.6%) there were 77 granulomas or prosthetic expositions (11.3% [6.7% in the vaginal anterior wall, 2.1% in the vaginal posterior wall and 4.8% in the fornix]), 80 prosthetic retractions (11.7%), 36 relapse of prolapse (6.9%) and 37 SUI de novo (5.4%). Multivaried analysis shows that previous history of hysterectomy or placing of an isolated anterior prosthesis increase the risk of peri-surgical complication; preserved uterus and isolated posterior prosthesis lessen the risk of granulomas and prosthetic retractions; and association of a Richter's intervention increases the rate of prosthetic retractions. Conclusion:, Cure of genital prolapse with synthetic prostheses interposed by vaginal route is now reliable and can be reproduced with a low rate of peri- and early post-surgical complications. However, our study shows a certain number of late post-surgical complications after insertion of strengthening synthetic vaginal implants (prosthetic expositions and prosthetic retractions). These retrospective results will soon be compared to a prospective study. [source]