974 resultados para CLASS-2 INTEGRONS
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Cellular responses to LPS, the major lipid component of the outer membrane of Gram-negative bacteria, are enhanced markedly by the LPS-binding protein (LBP), a plasma protein that transfers LPS to the cell surface CD14 present on cells of the myeloid lineage. LBP has been shown previously to potentiate the host response to LPS. However, experiments performed in mice with a disruption of the LBP gene have yielded discordant results. Whereas one study showed that LBP knockout mice were resistant to endotoxemia, another study did not confirm an important role for LBP in the response of mice challenged in vivo with low doses of LPS. Consequently, we generated rat mAbs to murine LBP to investigate further the contribution of LBP in experimental endotoxemia. Three classes of mAbs were obtained. Class 1 mAbs blocked the binding of LPS to LBP; class 2 mAbs blocked the binding of LPS/LBP complexes to CD14; class 3 mAbs bound LBP but did not suppress LBP activity. In vivo, class 1 and class 2 mAbs suppressed LPS-induced TNF production and protected mice from lethal endotoxemia. These results show that the neutralization of LBP accomplished by blocking either the binding of LPS to LBP or the binding of LPS/LBP complexes to CD14 protects the host from LPS-induced toxicity, confirming that LBP is a critical component of innate immunity.
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Catalase is an important virulence factor for survival in macrophages and other phagocytic cells. In Chlamydiaceae, no catalase had been described so far. With the sequencing and annotation of the full genomes of Chlamydia-related bacteria, the presence of different catalase-encoding genes has been documented. However, their distribution in the Chlamydiales order and the functionality of these catalases remain unknown. Phylogeny of chlamydial catalases was inferred using MrBayes, maximum likelihood, and maximum parsimony algorithms, allowing the description of three clade 3 and two clade 2 catalases. Only monofunctional catalases were found (no catalase-peroxidase or Mn-catalase). All presented a conserved catalytic domain and tertiary structure. Enzymatic activity of cloned chlamydial catalases was assessed by measuring hydrogen peroxide degradation. The catalases are enzymatically active with different efficiencies. The catalase of Parachlamydia acanthamoebae is the least efficient of all (its catalytic activity was 2 logs lower than that of Pseudomonas aeruginosa). Based on the phylogenetic analysis, we hypothesize that an ancestral class 2 catalase probably was present in the common ancestor of all current Chlamydiales but was retained only in Criblamydia sequanensis and Neochlamydia hartmannellae. The catalases of class 3, present in Estrella lausannensis and Parachlamydia acanthamoebae, probably were acquired by lateral gene transfer from Rhizobiales, whereas for Waddlia chondrophila they likely originated from Legionellales or Actinomycetales. The acquisition of catalases on several occasions in the Chlamydiales suggests the importance of this enzyme for the bacteria in their host environment.
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Peptide hormones within the secretin-glucagon family are expressed in endocrine cells of the pancreas and gastrointestinal epithelium and in specialized neurons in the brain, and subserve multiple biological functions, including regulation of growth, nutrient intake, and transit within the gut, and digestion, energy absorption, and energy assimilation. Glucagon, glucagon-like peptide-1, glucagon-like peptide-2, glucose-dependent insulinotropic peptide, growth hormone-releasing hormone and secretin are structurally related peptides that exert their actions through unique members of a structurally related G protein-coupled receptor class 2 family. This review discusses advances in our understanding of how these peptides exert their biological activities, with a focus on the biological actions and structural features of the cognate receptors. The receptors have been named after their parent and only physiologically relevant ligand, in line with the recommendations of the International Union of Pharmacology Committee on Receptor Nomenclature and Drug Classification (NC-IUPHAR).
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[cat] Una qüestió clau sobre la producció de salut relativament poc explorada es refereix a la influència dels factors socioeconòmics i mediambientals sobre el pes i l’obesitat. Aquesta problemàtica adquireix particular rellevància quan es comparen dos països Mediterranis com Itàlia i Espanya. És interessant adonar-se que l’obesitat a Espanya és 5 punts percentual més elevada al 2003 mentre que a l’any 1990 era aproximadament la mateixa en ambdós països. Aquesta article presenta una descomposició no lineal dels gaps o diferencials en taxes de sobrepès (índex de massa corporal – IMC- entre 25 i 29.9 9 kg/m2), obesitat classe 1 (IMC≥30 kg/m2) i classe 2 (IMC≥35 kg/m2) entre Espanya i Itàlia per gènere i grups d’edat. En explicar aquests gaps entre països aïllem les influències dels estils de vida, els efectes socioeconòmics i els mediambientals. Els nostres resultats indiquen que quan no es controla pels efectes mediambientals (efectes de grup o ‘peer effects’) els hàbits alimentaris i el nivell educatiu són els principals predictors del gaps totals entre països (36-52%), si bé aquests dos factors exerceixen un impacte diferenciat segons gènere i edat. Un tant paradoxalment, quan controlem pels efectes de grup aquests predictors perden la seva capacitat explicativa i els efectes de grup passen a explicar entre el 46-76% dels gaps en sobrepès i obesitat i mostren un patró creixent amb l’edat.
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With the implementation of the 2000 Q-MC specification, an incentive is provided to produce an optimized gradation to improve placement characteristics. Also, specifications for slip-formed barrier rail have changed to require an optimized gradation. Generally, these optimized gradations have been achieved by blending an intermediate aggregate with the coarse and fine aggregate. The demand for this intermediate aggregate has been satisfied by using crushed limestone chips developed from the crushing of the parent concrete stone. The availability, cost, and physical limitations of crushed limestone chips can be a concern. A viable option in addressing these concerns is the use of gravel as the intermediate aggregate. Unfortunately, gravels of Class 3I durability are limited to a small geographic area in Mississippi river sands north of the Rock River. Class 3 or Class 2 durability gravels are more widely available across the state. The durability classification of gravels is based on the amount and quality of the carbonate fraction of the material. At present, no service histories or research exists to assess the impact of using Class 3 or 2 durability gravels would have on the long-term durability of Portland cement concrete (PCC) pavement requiring Class 3I aggregate.
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BACKGROUND: We reviewed the current evidence on the benefit and harm of pre-hospital tracheal intubation and mechanical ventilation after traumatic brain injury (TBI). METHODS: We conducted a systematic literature search up to December 2007 without language restriction to identify interventional and observational studies comparing pre-hospital intubation with other airway management (e.g. bag-valve-mask or oxygen administration) in patients with TBI. Information on study design, population, interventions, and outcomes was abstracted by two investigators and cross-checked by two others. Seventeen studies were included with data for 15,335 patients collected from 1985 to 2004. There were 12 retrospective analyses of trauma registries or hospital databases, three cohort studies, one case-control study, and one controlled trial. Using Brain Trauma Foundation classification of evidence, there were 14 class 3 studies, three class 2 studies, and no class 1 study. Six studies were of adults, five of children, and three of both; age groups were unclear in three studies. Maximum follow-up was up to 6 months or hospital discharge. RESULTS: In 13 studies, the unadjusted odds ratios (ORs) for an effect of pre-hospital intubation on in-hospital mortality ranged from 0.17 (favouring control interventions) to 2.43 (favouring pre-hospital intubation); adjusted ORs ranged from 0.24 to 1.42. Estimates for functional outcomes after TBI were equivocal. Three studies indicated higher risk of pneumonia associated with pre-hospital (when compared with in-hospital) intubation. CONCLUSIONS: Overall, the available evidence did not support any benefit from pre-hospital intubation and mechanical ventilation after TBI. Additional arguments need to be taken into account, including medical and procedural aspects.
Resumo:
[cat] Una qüestió clau sobre la producció de salut relativament poc explorada es refereix a la influència dels factors socioeconòmics i mediambientals sobre el pes i l’obesitat. Aquesta problemàtica adquireix particular rellevància quan es comparen dos països Mediterranis com Itàlia i Espanya. És interessant adonar-se que l’obesitat a Espanya és 5 punts percentual més elevada al 2003 mentre que a l’any 1990 era aproximadament la mateixa en ambdós països. Aquesta article presenta una descomposició no lineal dels gaps o diferencials en taxes de sobrepès (índex de massa corporal – IMC- entre 25 i 29.9 9 kg/m2), obesitat classe 1 (IMC≥30 kg/m2) i classe 2 (IMC≥35 kg/m2) entre Espanya i Itàlia per gènere i grups d’edat. En explicar aquests gaps entre països aïllem les influències dels estils de vida, els efectes socioeconòmics i els mediambientals. Els nostres resultats indiquen que quan no es controla pels efectes mediambientals (efectes de grup o ‘peer effects’) els hàbits alimentaris i el nivell educatiu són els principals predictors del gaps totals entre països (36-52%), si bé aquests dos factors exerceixen un impacte diferenciat segons gènere i edat. Un tant paradoxalment, quan controlem pels efectes de grup aquests predictors perden la seva capacitat explicativa i els efectes de grup passen a explicar entre el 46-76% dels gaps en sobrepès i obesitat i mostren un patró creixent amb l’edat.
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INTRODUCTION: Gamma knife surgery (GKS) for vestibular schwannomas (VS) has a long-term clinical and scientific track record. After a period of de-escalation of dose prescription, results show a high rate of tumor control with improvement of clinical outcome (less than 1% facial palsy, 50-70% hearing preservation). Régis et al. (J Neurosurg 2013;119 Suppl.:105-11) suggested recently that proactive GKS management in intracanalicular tumors is better than a « wait and see » strategy when hearing is still useful at the time of diagnosis. MATERIALS AND METHODS: Based on these previous findings, we prospectively analyzed 190 vestibular schwannomas (VS), treated with GKS as first intention over a period of 4 years (2010-2014). We concentrated on patient, tumor and dosimetric characteristics. Special attention was given on the dose to the cochlea and its impact in maintaining serviceable hearing. RESULTS: The mean follow-up period was 1.3years (range 0.6-3.6). Preoperative serviceable hearing was present in 63.11% patients. The mean maximal diameter was 15.1mm (range 5-29.5). The size and volume of the tumor corresponded to Koos grade I, II, III and IV in 15.9%, 34.8%, 45.4% and 3.8% of the cases, respectively. The mean target volume was 1.24cm(3) (0.017-7.8). The mean prescription isodose volume was 1.6 cc (0.032-8.5). The mean marginal dose was 12Gy (11-12). The mean maximal dose received by the cochlea in patients with GR class 1 and 2 was 4.1Gy (1.5-7.6). Our preliminary neuroradiological follow-up shows 97% tumor control, with 45% shrinkage. Patients presenting with GR class 1 and class 2 at baseline retained serviceable hearing in 85% of cases. Among the patients with a follow-up of at least one year, those with Koos I tumors had the highest probability to maintain identical level of hearing after GKS. CONCLUSION: Our preliminary data suggest that Koos I patients should be treated early with GKS, before tumor growth and/or hearing deterioration, as they have the highest probability of hearing preservation.
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PURPOSE: To evaluate the clinical characteristics of the 3 classifications of vitreous seeds in retinoblastoma-dust (class 1), spheres (class 2), and clouds (class 3)-and their responses to intravitreal melphalan. DESIGN: Retrospective, bi-institutional cohort study. PARTICIPANTS: A total of 87 patient eyes received 475 intravitreal injections of melphalan (median dose, 30 μg) given weekly, a median of 5 times (range, 1-12 times). METHODS: At presentation, the vitreous seeds were classified into 3 groups: dust, spheres, and clouds. Indirect ophthalmoscopy, fundus photography, ultrasonography, and ultrasonic biomicroscopy were used to evaluate clinical response to weekly intravitreal melphalan injections and time to regression of vitreous seeds. Kaplan-Meier estimates of time to regression and ocular survival, patient survival, and event-free survival (EFS) were calculated and then compared using the Mantel-Cox test of curve. MAIN OUTCOME MEASURES: Time to regression of vitreous seeds, patient survival, ocular survival, and EFS. RESULTS: The difference in time to regression was significantly different for the 3 seed classes (P < 0.0001): the median time to regression was 0.6, 1.7, and 7.7 months for dust, spheres, and clouds, respectively. Eyes with dust received significantly fewer injections and a lower median and cumulative dose of melphalan, whereas eyes with clouds received significantly more injections and a higher median and cumulative dose of melphalan. Overall, the 2-year Kaplan-Meier estimates for ocular survival, patient survival, and EFS (related to target seeds) were 90.4% (95% confidence interval [CI], 79.7-95.6), 100%, and 98.5% (95% CI, 90-99.7), respectively. CONCLUSIONS: The regression and response of vitreous seeds to intravitreal melphalan are different for each seed classification. The vitreous seed classification can be predictive of time to regression, number, median dose, and cumulative dose of intravitreal melphalan injections required.
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Työssä määritettiin luokan 2 eläinperäisistä sivutuotteista liikennekäyttöön tuotettujen biodieselin ja biometaanin elinkaaren aikaiset kasvihuonekaasupäästöt ja tuotantoprosessien energiankulutukset perustuen kirjallisuuslähteistä saatuihin lähtötietoihin. Tätä kautta tutkittiin yhdistelmäprosessia, jossa tuotetaan molempia polttoaineita ja selvitettiin onko tällaisella tuotantotavalla mahdollista vähentää päästöjä ja parantaa polttoaineiden tuotannon energiatehokkuutta. Kasvihuone-kaasupäästöjen laskentamenetelmä pohjautuu direktiivissä 2009/28/EY annettuun ohjeistukseen ja eri kasvihuonekaasupäästöjen karakterisointi IPCC:n sadan vuoden tarkastelumalliin. Käytännön laskenta suoritettiin standardien SFS-EN ISO 14040 ja 14044 määrittelemän elinkaariarviointiselvityksen muodossa. Työssä käytetyn laskentamenetelmän ja tarkasteluun valittujen tuotanto-teknologioiden perusteella lasketut tulokset osoittavat, että yhdistelmäprosessilla ei saavuteta suurempia päästövähenemiä eikä parempaa energiatehokkuutta kuin nykyisin käytössä olevilla tuotantotavoilla. Tulokset ovat kuitenkin hyvin herkkiä laskennassa tehtyjen oletusten ja käytettyjen lähtötietojen vaihtelulle sekä valittujen laskentamenetelmien muutoksille. Suurin päästöjä ja energiankulutusta aiheuttava yksittäinen tekijä on kaikissa tuotejärjestelmissä luokan 2 sivutuotteiden esikäsittelyssä vaadittavaan steri-lointiin tarvittavan lämmön tuotanto. Tutkituissa tuotejärjestelmissä lämpö tuotetaan kokonaan tai osittain fossiilisilla polttoaineilla. Kasvihuone-kaasupäästöjä olisi mahdollista alentaa merkittävästi siirtymällä lämmön tuotannossa kokonaan uusiutuviin polttoaineisiin. Sterilointi on lain edellyttämä käsittelytapa ja siksi energiankulutusta on vallitsevissa olosuhteissa hyvin vaikea pienentää merkittävästi.
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Variations in egg length were observed for two populations of cryptic species of Anastrepha fraterculus (Wiedemann). The eggs of type I flies were smaller than those of type II individuals. For both types, in regard to yolk mass extrusion, four classes of embryos were detected. Class 1: embryos that extrude masses at both extremities; class 2: embryos in which extrusion occurs only at the anterior pole; class 3: embryos that eliminate mass only at the posterior pole, and class 4: embryos that do not extrude any mass. Embryo class frequencies were similar for populations belonging to the same type, but different between types. Individual females may produce eggs from different embryo classes, but for any given female the pattern remains constant during a long period of oviposition. Variation in size of the extruded masses was similar for both populations. Individual females produced embryos with a small range of mass diameters, and different females produced masses of different mean size. However, individual mass size remained constant during oviposition. The results suggest the existence of genetic components involved in the control of this unusual process. Larvae of both types presented, just before eclosion, similar unusual behaviors: they ingest the anterior extruded mass, rotate 180°, absorb the posterior mass and eclose near the posterior pole. Data show that cryptic A. fraterculus type I and type II differs in regard to egg size as well as to the phenomenon of yolk mass extrusion
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Double grade S420MH/S355J2H – rakenneputki on Ruukin kylmämuovattujen rakenneputkien vakioteräslaji. Se voidaan mitoittaa joko lujuusluokan S355 tai S420 mukaisesti. Teräslajin S355 mukaisesti mitoitettaessa on suunnittelu yksinkertaista. Painonsäästöä ja pidennettyjä jännevälejä haluttaessa käytetään lujuusluokan S420 mukaista mitoitusta. Työn tavoitteena oli selvittää kylmämuovattujen teräsrakenneputkien todellinen puristuskestävyys. Eurocode 3:n mukaan kylmämuovatut teräsrakenneputket kuuluvat nurjahduskäyrälle c. Tutkimukseen valittiin viisi eri profiilia olevaa rakenneputkea, joiden poikkileikkausluokat olivat 1, 2, 3 ja 4. Käytettäessä rakenneputkia puristussauvoina, on teräksen käyttö tehokkainta poikkileikkausluokassa 3, lähellä poikkileikkausluokkaa 4. Rakenneputkista laskettiin muunnetun hoikkuuden arvoilla 0.1, 0.5, 1.0 ja 1.5 koesauvojen pituudet kaikille profiileille. Valmistettiin kolme samanlaista koesauvaa jokaisesta koosta ja puristuskokeita suoritettiin yhteensä 57 kappaletta. Koesauvojen todelliset pituudet, alkukäyryydet ja poikkileikkaukset mitattiin. Ainestodistuksista saatiin materiaalin todelliset lujuudet. Laskettiin Eurocode 3:n mukaisesti kestävyydet nurjahduskäyrille a, b ja c. Laskennallisia kestävyyksiä verrattiin puristuskokeiden tuloksiin. Puristuskokeiden tulosten perusteella voidaan b-käyrää pitää oikeana profiileille 100x100x3, 150,150x5 ja 200x200x6. Profiili 150x150x5 kuuluu poikkileikkausluokkaan 2. Profiilit 100x100x3 ja 200x200x6 kuuluvat poikkileikkausluokkaan 4. Profiili 50x50x2 kuuluu nurjahduskäyrälle c. Profiilin poikkileikkausluokka on 1 ja aiemmat tutkimukset tukevat nurjahduskäyrän c käyttöä. Profiilista 300x300x8.8 ei saatu testattua täyttä sarjaa sen suuren kapasiteetin rikottua testilaitteiston, mutta puristuskokeiden perusteella se kuuluu nurjahduskäyrälle b. Profiili kuuluu poikkileikkausluokkaan 4.
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Depuis le début des années 80, les systèmes d’éducation à travers le monde recommandent l’intégration des élèves malentendants en classe ordinaire. Malgré l’utilisation d’aides auditives et de système MF, les élèves vivent des périodes où l’amplification reçue est insuffisante ou non optimale. Ces périodes sont causées par des facteurs influençant leurs conditions de communication et cela peut nuire à leurs apprentissages. Pourtant, les études sur ces situations vécues par les élèves ont très peu considéré leur point de vue. L’étude présentée vise à 1) de documenter les perceptions des situations de communication en classe mentionnées par des élèves malentendants intégrés, appareillés et ayant un système MF décerné ou rapportées à des professionnels; 2) de comprendre le contexte dans lequel des conditions non optimales de communication surviennent; 3) d’identifier les stratégies compensatoires rapportées par l’élève ou son locuteur ou déployées lors de leur participation aux activités de classe. Cette étude de cas multiples combine des données qualitatives et quantitatives recueillies à partir d’entrevues en profondeur auprès de huit élèves malentendants, de courtes entrevues avec leur enseignant et leur intervenant principal et une session d’observation en classe au cours de laquelle le niveau de bruit a été mesuré et les positions de l’enseignant ont été notées. Les données ont été analysées de manière longitudinale afin de décrire les participants et transversale afin de les comparer. Les résultats montrent que les élèves malentendants parlent de leurs situations de communication en classe, surtout les plus difficiles en associant toutes leurs difficultés au locuteur ou au milieu et non à eux-mêmes. Pour ce qui est du contexte, des niveaux élevés de bruit ont été mesurés et les positions des enseignants montrent qu’ils sont généralement loin de l’enfant malentendant ou qu’ils ne lui font pas face. Par ailleurs, les enseignants mentionnent ne pas avoir assez d’informations pour bien venir en aide à ces élèves. Enfin, les élèves et leurs enseignants utilisent différentes stratégies de communication, mais celles-ci ne sont pas toujours efficaces pour faciliter la communication. Toutes ces constatations mènent à des pistes de solutions visant à améliorer les situations de communication en classe et le contexte dans lequel les élèves apprennent, notamment l’accroissement des connaissances des divers acteurs et de leur collaboration entre eux.
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This study aimed at detecting the prevalence of antibiotic-resistant serotypes of Escherichia coli in Cochin estuary, India. E. coli strains were isolated during the period January 2010–December 2011 from five different stations set at Cochin estuary. Water samples from five different stations in Cochin estuary were collected on a monthly basis for a period of two years. Isolates were serotyped, antibiogram-phenotyped for twelve antimicrobial agents, and genotyped by polymerase chain reaction for uid gene that codes for β-D-glucuronidase. These E. coli strains from Cochin estuary were tested against twelve antibiotics to determine the prevalence of multiple antibiotic resistance among them. The results revealed that more than 53.33% of the isolates were multiple antibiotic resistant. Thirteen isolates showed resistance to sulphonamides and two of them contained the sul 1 gene. Class 1 integrons were detected in two E. coli strains which were resistant to more than seven antibiotics. In the present study, O serotyping, antibiotic sensitivity, and polymerase chain reaction were employed with the purpose of establishing the present distribution of multiple antibiotic-resistant serotypes, associated with E. coli isolated from different parts of Cochin estuary.
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The diversity and load of heterotrophic bacteria and fungi associated with the mangrove soil from Suva, Fiji Islands, was determined by using the plate count method. The ability of the bacterial isolates to produce various hydrolytic enzymes such as amylase, gelatinase and lipase were determined using the plate assay. The heterotrophic bacterial load was considerably higher than the fungal load. There was a predominance of the gram positive genus, Bacillus. Other genera encountered included Staphylococcus, Micrococcus, Listeria and Vibrio. Their effectiveness on the degradation of commercial polythene carry bags made of high density polyethylene (HDPE) and low density polyethylene (LDPE) was studied over a period of eight weeks in the laboratory. Biodegradation was measured in terms of mean weight loss, which was nearly 5 % after a period of eight weeks. There was a significant increase in the bacterial load of the soil attached to class 2 (HDPE) polythene. After eight weeks of submergence in mangrove soil, soil attached to class 1 and class 3 polythene mostly had Bacillus (Staphylococcus predominated in class 2 polythene). While most of the isolates were capable of producing hydrolytic enzymes such as amylase and gelatinase, lipolytic activity was low. Class 2 HDPE suffered the greatest biodegradation.