Why do we not find polyps in the lungs? Bronchial mucosa as a model in the treatment of polyposis

The link between lower and upper airways has been reported since the beginning of 1800s. They share the same pseudostratified ciliated columnar epithelium lining and the concept of one airway, one disease is quite well widespread. Nasal polyposis and asthma share basically the same inflammatory process: predominant infiltration of eosinophils, mucus cell hyperplasia, edema, thickened basal membrane, polarization for Th2 cell immune response, similar pro-inflammatory mediators are increased, for example cysteinyl leukotrienes. If the lower and upper airways share a lot of common epithelial structural features so why is the edema in the nasal mucosa able to increase so much the size of the mucosa to the point of developing polyps? The article tries to underline some differences between the nasal and the bronchial mucosa that could be implicated in this aberrant change from normal mucosa to polyps. This paper creates the concept that there are no polyps with the features of nasal polyposis disease in the lower airway and through it is developed the hypothesis of the nasal polyps origin could partially lie on the difference between the upper and lower airway histology. (C) 2012 Elsevier Ltd. All rights reserved.

Hyperbaric Oxygen Therapy Induces Kidney Protection in an Ischemia/Reperfusion Model in Rats

Ischemia/reperfusion (I/R) injury remains a major cause of graft dysfunction, which impacts short- and long-term follow-up. Hyperbaric oxygen therapy (HBO), through plasma oxygen transport, has been currently used as an alternative treatment for ischemic tissues. The aim of this study was to analyze the effects of HBO on kidney I/R injury model in rats, in reducing the harmful effect of I/R. The renal I/R model was obtained by occluding bilateral renal pedicles with nontraumatic vascular clamps for 45 minutes, followed by 48 hours of reperfusion. HBO therapy was delivered an hypebaric chamber (2.5 atmospheres absolute). Animals underwent two sessions of 60 minutes each at 6 hours and 20 hours after initiation of reperfusion. Male Wistar rats (n = 38) were randomized into four groups: sham, sham operated rats; Sham+HBO, sham operated rats exposed to HBO; I/R, animals submitted to I/R; and I/R+HBO, I/R rats exposed to HBO. Blood, urine, and kidney tissue were collected for biochemical, histologic, and immunohistochemical analyses. The histopathological evaluation of the ischemic injury used a grading scale of 0 to 4. HBO attenuated renal dysfunction after ischemia characterized by a significant decrease in blood urea nitrogen (BUN), serum creatinine, and proteinuria in the I/R+HBO group compared with I/R alone. In parallel, tubular function was improved resulting in significantly lower fractional excretions of sodium and potassium. Kidney sections from the I/R plus HBO group showed significantly lower acute kidney injury scores compared with the I/R group. HBO treatment significantly diminished proliferative activity in I/R (P < .05). There was no significant difference in macrophage infiltration or hemoxygenase-1 expression. In conclusion, HBO attenuated renal dysfunction in a kidney I/R injury model with a decrease in BUN, serum creatinine, proteinuria, and fractional excretion of sodium and potassium, associated with reduced histological damage.

Solvent-Resistant Polymeric Sensors for Adulteration Detection in Liquid Fuels

Polymeric sensors with improved resistance to organic solvents were produced via the layer-by-layer thin film deposition followed by chemical cross-linking. According to UV-vis spectroscopy, the mass loss of polyaniline/poly(vinyl alcohol) and polyaniline/novolac-type resin based films deposited onto glass slides was less than 20% when they were submitted to successive immersions (up to 3,000 immersion cycles) into commercially available ethanol and gasoline fuel samples. Polyallylamine hydrochloride/nickel tetrasulfonated phthalocyanine films presented similar stability. The electrical responses assessed by impedance spectroscopy of films deposited onto Au-interdigitated microelectrodes were relatively unaffected after continuous or cyclic immersions into both fuels. After these studies, an array including these polymeric sensors was employed to detect adulteration in ethanol and gasoline samples. After principal component analysis, it was possible to conclude that the proposed sensor array is capable to discriminate with remarkable reproducibility ethanol samples containing different amounts of water or else gasoline samples containing different amounts of ethanol. In both examples, more than 90% of data variance was retained in the first principal component. For each type of sample, ethanol and gasoline, it was found a linear correlation between one of the principal components and the sample's composition. These findings allow one to conclude that these films present great potential for the development of reliable and low-cost sensors for fuel analysis in liquid phase.

Multitemporal analysis of satellite imagery: implementation of a land evolution model in ALCS (ATSR LAND CLASSIFICATION SYSTEM)

In this report it was designed an innovative satellite-based monitoring approach applied on the Iraqi Marshlands to survey the extent and distribution of marshland re-flooding and assess the development of wetland vegetation cover. The study, conducted in collaboration with MEEO Srl , makes use of images collected from the sensor (A)ATSR onboard ESA ENVISAT Satellite to collect data at multi-temporal scales and an analysis was adopted to observe the evolution of marshland re-flooding. The methodology uses a multi-temporal pixel-based approach based on classification maps produced by the classification tool SOIL MAPPER ®. The catalogue of the classification maps is available as web service through the Service Support Environment Portal (SSE, supported by ESA). The inundation of the Iraqi marshlands, which has been continuous since April 2003, is characterized by a high degree of variability, ad-hoc interventions and uncertainty. Given the security constraints and vastness of the Iraqi marshlands, as well as cost-effectiveness considerations, satellite remote sensing was the only viable tool to observe the changes taking place on a continuous basis. The proposed system (ALCS – AATSR LAND CLASSIFICATION SYSTEM) avoids the direct use of the (A)ATSR images and foresees the application of LULCC evolution models directly to „stock‟ of classified maps. This approach is made possible by the availability of a 13 year classified image database, conceived and implemented in the CARD project (http://earth.esa.int/rtd/Projects/#CARD).The approach here presented evolves toward an innovative, efficient and fast method to exploit the potentiality of multi-temporal LULCC analysis of (A)ATSR images. The two main objectives of this work are both linked to a sort of assessment: the first is to assessing the ability of modeling with the web-application ALCS using image-based AATSR classified with SOIL MAPPER ® and the second is to evaluate the magnitude, the character and the extension of wetland rehabilitation.

Continuous intrathecal glyceryl trinitrate prevents delayed cerebral vasospasm in the single-SAH rabbit model in vivo

Delayed cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) is a major cause of high morbidity and mortality. The reduced availability of nitric oxide (NO) in blood and cerebrospinal fluid (CSF) is well established as a key mechanism of vasospasm. Systemic administration of glyceryl trinitrate (GTN), an NO donor also known as nitroglycerin, has failed to be established in clinical settings to prevent vasospasm because of its adverse effects, particularly hypotension. The purpose of this study was to analyze the effect of intrathecally administered GTN on vasospasm after experimental SAH in the rabbit basilar artery.

Characterization of Giardia lamblia WB C6 clones resistant to nitazoxanide and to metronidazole

OBJECTIVES: The characterization of Giardia lamblia WB C6 strains resistant to metronidazole and to the nitro-thiazole nitazoxanide [2-acetolyloxy-N-(5-nitro 2-thiazolyl) benzamide] as the parent compound of thiazolides, a novel class of anti-infective drugs with a broad spectrum of activities against a wide variety of helminths, protozoa and enteric bacteria. METHODS: Issuing from G. lamblia WB C6, we have generated two strains exhibiting resistance to nitazoxanide (strain C4) and to metronidazole (strain C5) and determined their susceptibilities to both drugs. Using quantitative RT-PCR, we have analysed the expression of genes that are potentially involved in resistance formation, namely genes encoding pyruvate oxidoreductases (POR1 and POR2), nitroreductase (NR), protein disulphide isomerases (PDI2 and PDI4) and variant surface proteins (VSPs; TSA417). We have cloned and expressed PDI2 and PDI4 in Escherichia coli. Using an enzyme assay based on the polymerization of insulin, we have determined the activities of both enzymes in the presence and absence of nitazoxanide. RESULTS: Whereas C4 was cross-resistant to nitazoxanide and to metronidazole, C5 was resistant only to metronidazole. Transcript levels of the potential targets for nitro-drugs POR1, POR2 and NR were only slightly modified, PDI2 transcript levels were increased in both resistant strains and PDI4 levels in C4. This correlated with the findings that the functional activities of recombinant PDI2 and PDI4 were inhibited by nitazoxanide. Moreover, drastic changes were observed in VSP gene expression. CONCLUSIONS: These results suggest that resistance formation in Giardia against nitazoxanide and metronidazole is linked, and possibly mediated by, altered gene expression in drug-resistant strains compared with non-resistant strains of Giardia.

Cerebral revascularization model in a swine

The purpose of this study was to analyze the suitability of the cerebral vasculature of the pig regarding a revascularization procedure. In two 60 kg pigs the femoral artery was exposed and canulated for selective angiography and interventional procedures. After the angiography, the pigs were brought to the animal OR for craniotomy and analysis of the intracranial cerebral arteries and the surgical exposure of the carotid arteries under the microscope. Angiography demonstrated the presence of a true internal-, external carotid artery and vertebral arteries. Both the vertebral and internal carotid arteries are feeding a rete mirabilis both at the cranial base and the cranio-cervical junction. At these sites further advancement of the angiography catheter was not possible. Out of these rete mirabilis, an intracranial carotid artery and an intracranial vertebral artery were formed, respectively. The intracranial cerebral vessels were of the dimension of 1 mm and less. The extracranial portion of the internal carotid artery was 2.5 mm of diameter. From these findings, we conclude that a direct cerebral revascularization procedure of the intracranial vessels is not possible in the swine. However, a global revascularization procedure on the extracranial portion of the internal carotid artery is thus feasible, both using a low- and high-flow anastamosis technique.

Reynolds-stress turbulence model in the KIVA code for engine simulation

A Reynolds-Stress Turbulence Model has been incorporated with success into the KIVA code, a computational fluid dynamics hydrocode for three-dimensional simulation of fluid flow in engines. The newly implemented Reynolds-stress turbulence model greatly improves the robustness of KIVA, which in its original version has only eddy-viscosity turbulence models. Validation of the Reynolds-stress turbulence model is accomplished by conducting pipe-flow and channel-flow simulations, and comparing the computed results with experimental and direct numerical simulation data. Flows in engines of various geometry and operating conditions are calculated using the model, to study the complex flow fields as well as confirm the model’s validity. Results show that the Reynolds-stress turbulence model is able to resolve flow details such as swirl and recirculation bubbles. The model is proven to be an appropriate choice for engine simulations, with consistency and robustness, while requiring relatively low computational effort.

Ascorbic acid for amelioration of reperfusion injury in a lung autotransplantation model in sheep

BACKGROUND: Reperfusion injury is the leading cause of early graft dysfunction after lung transplantation. Activation of neutrophilic granulocytes with generation of free oxygen radicals appears to play a key role in this process. The efficacy of ascorbic acid as an antioxidant in the amelioration of reperfusion injury after lung transplantation has not been studied yet. METHODS: An in situ autotransplantation model in sheep is presented. The left lung was flushed (Euro-Collins solution) and reperfused; after 2 hours of cold storage, the right hilus was then clamped (group R [reference], n = 6). Group AA animals (n = 6) were treated with 1 g/kg ascorbic acid before reperfusion. Controls (group C, n = 6) underwent hilar preparation and instrumentation only. RESULTS: In group R, arterio-alveolar oxygen difference (AaDO2) and pulmonary vascular resistance (PVR) were significantly elevated after reperfusion. Five of 6 animals developed frank alveolar edema. All biochemical parameters showed significant PMN activation. In group AA, AaDO2, PVR, work of breathing, and the level of PMN activation were significantly lower. CONCLUSIONS: The experimental model reproduces all aspects of lung reperfusion injury reliably. Ascorbic acid was able to weaken reperfusion injury in this experimental setup.

Transcutaneous treatment with vetdrop(®) sustains the adjacent cartilage in a microfracturing joint defect model in sheep

The significance of the adjacent cartilage in cartilage defect healing is not yet completely understood. Furthermore, it is unknown if the adjacent cartilage can somehow be influenced into responding after cartilage damage. The present study was undertaken to investigate whether the adjacent cartilage can be better sustained after microfracturing in a cartilage defect model in the stifle joint of sheep using a transcutaneous treatment concept (Vetdrop(®)). Carprofen and chito-oligosaccharids were added either as single components or as a mixture to a vehicle suspension consisting of a herbal carrier oil in a water-in-oil phase. This mixture was administered onto the skin with the aid of a specific applicator during 6 weeks in 28 sheep, allocated into 6 different groups, that underwent microfracturing surgery either on the left or the right medial femoral condyle. Two groups served as control and were either treated intravenously or sham treated with oxygen only. Sheep were sacrificed and their medial condyle histologically evaluated qualitatively and semi-quantitatively according to 4 different scoring systems (Mankin, ICRS, Little and O'Driscoll). The adjacent cartilage of animals of group 4 treated transcutaneously with vehicle, chito-oligosaccharids and carprofen had better histological scores compared to all the other groups (Mankin 3.3±0.8, ICRS 15.7±0.7, Little 9.0±1.4). Complete defect filling was absent from the transcutaneous treatment groups. The experiment suggests that the adjacent cartilage is susceptible to treatment and that the combination of vehicle, chitooligosaccharids and carprofen may sustain the adjacent cartilage during the recovery period.

Construct Validity of the Pig Intestine Model in the Simulation of Laparoscopic Urethrovesical Anastomosis

Introduction: Laparoscopic training models are increasingly important in urology to allow trainees to improve their laparoscopic skills prior to going to the operating room. For a training model to be valid, it must correlate with performance in a real case. The model must also discriminate between experienced and inexperienced subjects. [See PDF for complete abstract]

Search for the neutral Higgs bosons of the Minimal Supersymmetric Standard Model in pp collisions at sqrts=7 TeV with the ATLAS detector

A search for neutral Higgs bosons of the Minimal Supersymmetric Standard Model (MSSM) is reported. The analysis is based on a sample of proton-proton collisions at a centre-of-mass energy of 7 TeV recorded with the ATLAS detector at the Large Hadron Collider. The data were recorded in 2011 and correspond to an integrated luminosity of 4.7 fb(-1) to 4.8 fb(-1). Higgs boson decays into oppositely-charged in muon or tau lepton pairs are considered for final states requiring either the presence or absence of b-jets. No statistically significant excess over the expected background is observed and exclusion limits at the 95% confidence level are derived. The exclusion limits are for the production cross-section of a generic neutral Higgs boson, phi, as a function of the Higgs boson mass and for h/A/H production in the MSSM as a function of the parameters m(A) and tan beta in the m(h)(max) scenario for m(A) in the range of 90 GeV to 500 GeV.

Correlation of urinary nitric oxide concentrations with the development of hip dysplasia in Labrador retrievers

Urinary nitric oxide was determined in terms of the ratio of the concentrations of total urinary nitrite and nitrate:creatinine in 40 juvenile labrador retrievers, and radiographic signs of hip dysplasia and distraction indices were investigated in the same dogs in later life. The ratio was correlated significantly with the Norberg angle and with subchondral sclerosis in both hips, and with the grade of dysplasia in each hip and the dogs' overall grade of hip dysplasia. No correlations were observed between the ratio and the distraction indices or other radiographic criteria for hip dysplasia.

Low-frequency drug-resistant HIV-1 and risk of virological failure to first-line NNRTI-based ART: a multicohort European case-control study using centralized ultrasensitive 454 pyrosequencing.

OBJECTIVES It is still debated if pre-existing minority drug-resistant HIV-1 variants (MVs) affect the virological outcomes of first-line NNRTI-containing ART. METHODS This Europe-wide case-control study included ART-naive subjects infected with drug-susceptible HIV-1 as revealed by population sequencing, who achieved virological suppression on first-line ART including one NNRTI. Cases experienced virological failure and controls were subjects from the same cohort whose viraemia remained suppressed at a matched time since initiation of ART. Blinded, centralized 454 pyrosequencing with parallel bioinformatic analysis in two laboratories was used to identify MVs in the 1%-25% frequency range. ORs of virological failure according to MV detection were estimated by logistic regression. RESULTS Two hundred and sixty samples (76 cases and 184 controls), mostly subtype B (73.5%), were used for the analysis. Identical MVs were detected in the two laboratories. 31.6% of cases and 16.8% of controls harboured pre-existing MVs. Detection of at least one MV versus no MVs was associated with an increased risk of virological failure (OR = 2.75, 95% CI = 1.35-5.60, P = 0.005); similar associations were observed for at least one MV versus no NRTI MVs (OR = 2.27, 95% CI = 0.76-6.77, P = 0.140) and at least one MV versus no NNRTI MVs (OR = 2.41, 95% CI = 1.12-5.18, P = 0.024). A dose-effect relationship between virological failure and mutational load was found. CONCLUSIONS Pre-existing MVs more than double the risk of virological failure to first-line NNRTI-based ART.

Preliminary study on carprofen concentration measurements after transcutaneous treatment with Vetdrop® in a microfracture joint defect model in sheep.

BackgroundThe present preliminary study describes concentration time courses of the NSAID carprofen in the plasma and synovial fluid in a microfrature sheep model after transcutaneous treatments with a novel application device (Vetdrop®). To treat circumscribed inflammatory processes a transcutaneous application device could potentially be beneficial. After transcutaneous application normally lower systemic concentrations are measured which may reduce the incidence of side effects, whereas efficacy is still maintained.In this study carprofen was used based on its capacity to provide analgesia after orthopaedic procedures in sheep and it is considered that it may have a positive influence on the healing of cartilage in low concentrations.ResultsIn all transcutaneously treated animals, carprofen plasma concentrations exceeded those of synovial fluid, although plasma levels remained significantly reduced (300-fold) as compared to carprofen administered intravenously. Furthermore, in contrast to the intravenously treated animals, a modest accumulation of carprofen in plasma and synovial fluid was observed in the transcutaneously treated animals over the 6-week treatment period.ConclusionsThe transcutaneously administered carprofen using the Vetdrop® device penetrated the skin and both, plasma- and synovial concentrations could be measured repeatedly over time. This novel device may be considered a valuable transcutaneous drug delivery system.