POLYETHYLENE GLYCOL ADDITION DOES NOT IMPROVE EXOGENOUS SURFACTANT FUNCTION IN AN EXPERIMENTAL MODEL OF MECONIUM ASPIRATION SYNDROME

Meconium (MEC) is a potent inactivator of pulmonary surfactant. The authors studied the effects of polyethylene glycol addition to the exogenous surfactant over the lung mechanics and volumes. Human meconium was administrated to newborn rabbits. Animals were ventilated for 20 minutes and dynamic compliance, ventilatory pressure, and tidal volume were recorded. Animals were randomized into 3 study groups: MEC group (without surfactant therapy); S100 group (100 mg/kg surfactant); and PEG group (100 mg/kg porcine surfactant plus 5% PEG). After ventilation, a pulmonary pressure-volume curve was built. Histological analysis was carried out to calculate the mean alveolar size (Lm) and the distortion index (DI). Both groups treated with surfactant showed higher values of dynamic pulmonary compliance and lower ventilatory pressure, compared with the MEC group (P .05). S100 group had a larger maximum lung volume, V30, compared with the MEC group (P .05). Lm and DI values were smaller in the groups treated with surfactant than in the MEC group (P .05). No differences were observed between the S100 and PEG groups. Animals treated with surfactant showed significant improvement in pulmonary function as compared to nontreated animals. PEG added to exogenous surfactant did not improve lung mechanics or volumes.

Stromal interleukin-1 expression in the cornea after haze-associated injury

The purpose of this study was to determine whether myofibroblasts or other cells in the stroma in the cornea produce interleukin (IL)-1 alpha or IL-1 beta that could modulate myofibroblast viability in corneas with haze after photorefractive keratectomy (PRK). Twenty-four female rabbits had haze-generating PRK for 9 diopters of myopia and were sacrificed at 1 week, 2 weeks, 3 weeks or 4 weeks after surgery. Corneal rims were removed, frozen in OCT at -80 degrees C, and analyzed by immunocytochemistry using primary antibodies to IL-1 alpha, IL-1 beta and alpha smooth muscle actin (SMA). Double immunostaining was performed for the co-localization of SMA with IL-1 alpha or IL-1 beta. Central dense haze and peripheral slight haze regions of each cornea were analyzed. SMA+ cells that expressed IL-1 alpha protein were detected in both regions of the corneas at most time points following PRK. However, in the haze region at the 1,3 and 4 week time points, significantly more (p < 0.01) SMA cells did not express IL-1 alpha. Also, in the haze region at all three time points, significantly more (p < 0.01) SMA- cells than SMA+ cells expressed interleukin-1 alpha protein. IL-1 beta expression patterns in SMA+ and SMA- stromal cells was similar to that of IL-1 alpha after PRK. Previous studies have demonstrated that IL-1 alpha or IL-1 beta triggers myofibroblast apoptosis in vitro, depending on the available concentration of apoptosis-suppressive TGFO. This study demonstrates that SMA- cells such as corneal fibroblasts, keratocytes, or inflammatory cells may produce IL-1 alpha and/or IL-1 beta that could act in paracrine fashion to regulate myofibroblast apoptosis-especially in the region where there is haze in the cornea after PRK was performed and SMA+ myofibroblasts are present at higher density. However, some SMA+ myofibroblasts themselves produce IL-1 alpha and/or IL-1 beta, suggesting that myofibroblast viability could also be regulated via autocrine mechanisms. (C) 2010 Elsevier Ltd. All rights reserved.

Chronic autoimmune urticaria as the first manifestation of juvenile systemic lupus erythematosus

Chronic urticaria (daily or almost daily symptoms lasting for more than six weeks) is characterized by wheals and erythema, with or without itching. A few case reports have shown chronic autoimmune urticaria at the beginning of systemic lupus erythematosus (SLE), particularly in adults. However, the prevalence of this manifestation in a lupus paediatric population was not studied. During 27 consecutive years, 5419 patients were followed up at our University Hospital and 271 (5%) had juvenile SLE (American College of Rheumatology criteria). Two of them (0.7%) had chronic and painless autoimmune urticaria as the first manifestation of juvenile SLE, and were reported herein. One case was a five-year old female with continuous widespread urticaria (duration 120 days), antinuclear antibodies (ANA) 1:640 (dense fine speckled pattern) and elevated complement levels. The juvenile SLE diagnosis was established after one year. The other case was a 13-year old female who had chronic widespread urticaria (lasting 45 days), ANA 1:160 (fine speckled pattern) and normal complement levels. The juvenile SLE diagnosis was established after three years. In conclusion, chronic autoimmune urticaria is very rare and may be the first lupus manifestation, particularly associated with the presence of autoantibodies. This study reinforces the importance of a rigorous follow-up in children and adolescents suffering from autoimmune urticaria due to the possibility of connective tissue disorders, such as paediatric lupus. Lupus (2011) 20, 763-766.

Cytoplasmic and nuclear localization of cadherin in honey bee (Apis mellifera L.) gonads

Cadherins are crucial molecules mediating cell-cell interactions between somatic and germline cells in insect and mammalian male and female gonads. We analysed the presence and localization of cadherins in ovaries of honeybee queens and in testes of drones. Transcripts representing two classical cadherins, E-cadherin (shotgun) and N-cadherin, as well as three protocadherins (Starry night, Fat and Fat-like) were detected in gonads of both sexes. Pan-cadherin antibodies, which most probably detect a honeybee N-cadherin, were used in immunolocalization analyses. In the germarium of ovarioles, cadherin-IR (cadherin immunoreactivity) was evidenced as homogeneously distributed in the cytoplasm and as nuclear foci, in both germline and somatic cells. It was also detected in polyfusomes and ring canals. In testiolar tubules, cadherin-IR showed a cytoplasmic and nuclear distributon alike in ovaries. The unexpected nuclear localization and cytoplasmic distribution in ovaries and testes were corroborated by immunogold electron microscopy, which revealed cadherin aggregates associated with electron-dense nuclear structures. With respect to cadherin localization, the honeybee differs from Drosophila, the model for gametogenesis in insects, raising the question as to how differences among solitary and social species may be built into and generated from the general architecture of polytrophic meroistic ovaries. It also indicates the possibility of divergent roles for cadherin in the functional architecture of insect gonads, in general, especially in taxa with high reproductive output.

Development of microemulsions to topically deliver 5-aminolevulinic acid in photodynamic therapy

The aim of this study was to obtain and to characterize microemulsions containing 5-aminolevulinic acid (5-ALA) and to investigate the influence of these systems in drug skin permeation for further topical photodynamic therapy (PDT). 5-ALA was incorporated in water-in-oil (W/O), bicontinuous (Bc), and oil-in-water (O/W) microemulsions obtained by the titration of ethyl oleate and PEG-8 caprylic/capric glycerides:polyglyceryl-6 dioleate (3:1) mixtures with water. Selected systems were characterized by conductivity, viscosity, size of the droplets, and drug release. The stability of the drug in the microemulsions was also assessed. Moreover, the in vitro and in vivo skin permeation of 5-ALA was investigated using diffusion cells and confocal scanning laser microscopy (CSLM), respectively. Despite the fact that the O/W microemulsion decreased the 5-ALA diffusion coefficient and retarded the drug release, it also significantly increased the in vitro drug skin permeation when compared to other 5-ALA carriers. It was observed by CSLM that the red fluorescence of the skin increased homogeneously in the deeper skin layers when the 5-ALA microemulsion was applied in vivo, probably due to the formation of the photoactive protoporphyrin IX. The microemulsion developed carried 5-ALA to the deeper skin layers, increasing the red fluorescence of the skin and indicating the potentiality of the system for topical 5-ALA-PDT. (C) 2010 Elsevier B.V. All rights reserved.

Enantioselectivity in the Pharmacokinetic Interaction Between Fluvastatin and Lercanidipine in Healthy Volunteers

Hypertension and dyslipidemia are independent risk factors for cardiovascular mortality and are frequently present in the same patient. Fluvastatin (FV), used to reduce cholesterol levels, and lercanidipine (LER), used to control blood pressured are marketed as racemic mixtures. Therapeutic activities are 30-fold higher for (+)-3R,5S-FV and 100- to 200-fold higher for S-LER compared with their respective antipodes. The present study describes the enantioselective pharmacokinetic interaction between LER and FV in healthy volunteers. A crossover randomized study was conducted in 3 phases on 8 volunteers treated with a single oral racemic dose of LER (20 mg) or FV (40 mg) or LER plus FV. Serial blood samples were collected from 0 to 24 hours. Plasma concentrations of the LER and FV enantiomers were determined by liquid chromatography/tandem mass spectrometry, and pharmacokinetic parameters were evaluated using the WinNonlin software. The Wilcoxon and Mann-Whitney tests (P < .05) were used to analyze enantiomer ratios and the pharmacokinetic drug interaction. Data are expressed as medians. In monotherapy, the kinetic disposition of both FV and LER was enantioselective. AUC values were significantly higher for (-)-3S,5R-FV than for (+)-3R,5S-FV (358.20 vs 279.68 ng.h/mL) and for S-LER compared with R-LER (13.90 vs 11.88 ng.h/mL). The pharmacokinetic parameters of FV were not enantioselective when combined with LER (AUC: (-)-3S,5R-FV: 325.21; (+)-3R,5S-FV: 316.44 ng.h/mL). There was a significant reduction in S-LER (8.06 vs 13.90 ng.h/mL) and R-LER (6.76 vs 11.88 ng.h/mL) AUC values when FV was coadministered. In conclusion, the interaction between FV-LER might be clinically relevant because AUC values of (+)-3R,5S-FV were increased when LER was coadministered, and AUC values of the 2 LER enantiomers were reduced when FV was coadministered.

Fibrinolytic activity is associated with presence of cystic medial degeneration in aneurysms of the ascending aorta

Fibrinolytic activity is associated with presence of cystic medial degeneration in aneurysms of the ascending aorta Aims: Thoracic ascending aortic aneurysms (TAA) are characterized by elastic fibre breakdown and cystic medial degeneration within the aortic media, associated with progressive smooth muscle cell (SMC) rarefaction. The transforming growth factor (TGF)-beta/Smad2 signalling pathway is involved in this process. Because the pericellular fibrinolytic system activation is able to degrade adhesive proteins, activate matrix metalloproteinase (MMP), induce SMC disappearance and increase the bioavailability of TGF-beta, the aim was to investigate the plasminergic system in TAA. Methods and results: Ascending aortas [21 controls and 19 TAAs (of three different aetiologies)] were analysed. Immunohistochemistry showed accumulation of t-PA, u-PA and plasmin in TAAs, associated with residual SMCs. Overexpression of t-PA and u-PA was confirmed by reverse transcription-polymerase chain reaction (RT-PCR), immunoblotting and zymography on TAA extracts and culture medium conditioned by TAA. Plasminogen was present on the SMC surface and inside cytoplasmic vesicles, but plasminogen mRNA was undetectable in the TAA medial layer. Plasmin-antiplasmin complexes were detected in TAA-conditioned medium and activation of the fibrinolytic system was associated with increased fibronectin turnover. Fibronectin-related material was detected immunohistochamically in dense clumps around SMCs and colocalized with latent TGF-beta binding protein-1. Conclusions: The fibrinolytic pathway could play a critical role in TAA progression, via direct or indirect impact on ECM and consecutive modulation of TGF-beta bioavailability.

Characteristics of Filiform, Fungiform and Vallate Papillae and Surface of Interface Epithelium-Connective Tissue of the Maned Sloth Tongue Mucosa (Bradypus torquatus, Iliger, 1811): Light and Scanning Electron Microscopy Study

The study of lingual surfaces and the surface of interface epithelium-connective tissue of the tongue of Bradypus torquatus was performed by employing the light and scanning electron microscopy (SEM) techniques. The results revealed that the rostral part of the tongue presents a round apex and covered by filiform and fungiform lingual papillae and a ventral smooth surface. It was observed that the epithelial layer of the dorsal surface possesses the basal, spinosum, granular and cornified epithelial cells. The lamina propria is characterized by a dense connective tissue forming the long, short and round papillae. Numerous typical filiform papillae are located especially in the rostral part intermingled for few fungiform papillae, which were revealed in three-dimensional SEM images. Usually, the fungiform papillae are located in the border of rostral apex of the tongue exhibiting the rounded form. They are covered by keratinized epithelial cells. In the fungiform papillae, several taste pores were observed on the surface. The vallate papillae presented numerous taste buds in the wall of epithelial cells, being that the major number of taste buds is located on the superior half of vallate papilla. The taste pores are surrounded by several laminae of keratinized epithelial cells. The samples treated with NaOH solution and examined by SEM revealed, after removal of the epithelial layer, the dense connective core in original disposition, presenting different sizes and shapes. The specimens stained with Picrosirius and examined by polarized light microscopy revealed the connective tissue, indicating the collagen fibres type I and type III.

Three-dimensional Characteristics of the Interface Epithelium-Connective Tissue Surface of Finger`s Lamina Propria of Cebus apella Monkey: Scanning Electron Microscopy Study

In the present paper were analysed the three-dimensional characteristics of the interface epithelium-connective tissue surface of finger prints of Cebus apella monkey employing the scanning electron microscopic methods. The connective tissue core (CTC) and epithelial papillae were examined verifying the three-dimensional configuration of the tissue projections. The samples were fixed in Bouin solsution for histologic preparations and in modified Karnovsky for examine to observe in scanning electron microscopy. After treatment in the 10% NaOH solution during 3 to 5 days, the surface of finger prints revealed a distribution of CTC of lamina propria in situ showing original three-dimensional SEM images. The linear and circular dispositions CTC, and the furrows were clearly identified. Each pointed papilla presented a large base and longitudinal disposition of thick collagen fiber bundles and in some areas with a complex reticular formations. The longitudinal furrows between the pointed papillae exhibited a dense layer of connective tissue and showed only low CTC or laminar in shape. The presence of numerous foramina of sweat gland were noted in three-dimensional SEM images.

High-pressure phase diagram of the drug mitotane in compressed and/or supercritical CO(2)

This work provides experimental phase diagram of mitotane, a drug used in the chemotherapy treatment of adrenocortical carcinoma, in compressed and/or supercritical CO(2). The synthetic-static method in a high-pressure variable-volume view cell coupled with a transmitted-light intensity probe was used to measure the solid-fluid (SF) equilibrium data. The phase equilibrium experiments were determined in temperature ranging from (298.2 to 333.1) K and pressure up to 22 MPa. Peng-Robinson equation of state (PR-EoS) with classical mixing rule was used to correlate the experimental data. Excellent agreement was found between experimental and calculated values. (C) 2009 Elsevier Ltd. All rights reserved.

Ultrastructure of Motor Nerve Terminals in the Anterior Third of Wistar Rat Tongue

The nerve terminals of intrinsic muscular fibers of the tongue of adult wistar rats was studied by using silver impregnation techniques, transmission electron microscopy (TEM), and high resolution scanning electron microscopy (HRSEM) to observe the nerve fibers and their terminals. Silver impregnation was done according to Winkelman and Schmit, 1957. For TEM, small blocks were fixed in modified Karnovsky solution, postfixed in 1% buffered osmium tetroxide solution, and embedded in Spurr resin. For HRSEM, the parts were fixed in 2% osmium tetroxide solution with 1/15 M sodium phosphate buffer (pH 7.4) at 4 degrees C for 2 h, according to the technique described by Tanaka, 1989. Thick myelinated nerve bundles were histologically observed among the muscular fibers. The intrafusal nerve fiber presented a tortuous pathway with punctiform terminal axons in clusters contacting the surface of sarcolemma. Several myelinated nerve fibers involved by collagen fibers of the endoneurium were observed in HRSEM in three-dimensional aspects. The concentric lamellae of the myelin sheath and the axoplasm containing neurofilaments interspersed among the mitochondria were also noted. In TEM, myofibrils, mitochondria, rough endoplasmic reticulum, Golgi`s apparatus, and glycogen granules were observed in sarcoplasm. It is also noted that the sarcomeres constituted by myofilaments with their A, I, and H bands and the electron dense Z lines. In areas adjacent to muscular fibers, there were myelinated and unmyelinated nerve fibers involved by endoneurium and perineurium. In the region of the neuromuscular junction, the contact with the sarcolemma of the muscular cell occurs forming several terminal buttons and showing numerous evaginations of the cell membrane. In the terminal button, mitochondria and numerous synaptic vesicles were observed. Microsc. Res. Tech. 72:464-470, 2009. (C) 2009 Wiley-Liss. Inc.

Placentation in the Amazonian manatee (Trichechus inunguis)

Evidence from several sources supports a close phylogenetic relationship between elephants and sirenians. To explore whether this was reflected in similar placentation, we examined eight delivered placentae from the Amazonian manatee using light microscopy and immunohistochemistry. In addition, the fetal placental circulation was described by scanning electron microscopy of vessel casts. The manatee placenta was zonary and endotheliochorial, like that of the elephant. The interhaemal barrier comprised maternal endothelium, cytotrophoblasts and fetal endothelium. We found columnar trophoblast beneath the chorionic plate and lining lacunae in this region, but there was no trace in the term placenta of haemophagous activity. The gross anatomy of the cord and fetal membranes was consistent with previous descriptions and included a four-chambered allantoic sac, as also found in the elephant and other afrotherians. Connective tissue septae descended from the chorionic plate and carried blood vessels to the labyrinth, where they gave rise to a dense capillary network. This appeared to drain into shorter vessels near the chorionic plate. The maternal vasculature could not be examined in the same detail, but maternal capillaries ran rather straight and roughly parallel to the fetal ones. Overall, there is a close resemblance in placentation between the manatee and the elephant.

Physical-mechanical properties of glass ionomer cements indicated for atraumatic restorative treatment

Background: This study evaluated mechanical properties of glass ionomer cements (GICs) used for atraumatic restorative treatment. Wear resistance, Knoop hardness (Kh), flexural (F(s)) and compressive strength (C(s)) were evaluated. The GICs used were Riva Self Cure (RVA), Fuji IX (FIX), Hi Dense (HD), Vitro Molar (VM), Maxxion R (MXR) and Ketac Molar Easymix (KME). Methods: Wear was evaluated after 1, 4, 63 and 365 days. Two-way ANOVA and Tukey post hoc tests (P = 0.05) analysed differences in wear of the GICs and the time effect. F(s), C(s), and Kh were analysed with one-way ANOVA. Results: The type of cement (p < 0.001) and the time (p < 0.001) had a significant effect on wear. In early-term wear and Kh, KME and FIX presented the best performance. In long-term wear, F(s) and C(s), KME, FIX and HD had the best performance. Strong explanatory power between F(s) and the Kh (r(2) = 0.85), C(s) and the Kh (r(2) = 0.82), long-term wear and F(s) of 24 h (r(2) = 0.79) were observed. Conclusions: The data suggested that KME and FIX presented the best in vitro performance. HD showed good results except for early-term wear.

Characterization of dimethacrylate polymeric networks: A study of the crosslinked structure formed by monomers used in dental composites

The resin phase of dental composites is mainly composed of combinations of dimethacrylate comonomers, with final polymeric network structure defined by monomer type/reactivity and degree of conversion. This fundamental study evaluates how increasing concentrations of the flexible triethylene glycol dimethacrylate (TEGDMA) influences void formation in bisphenol A diglycidyl dimethacrylate (BisGMA) co-polymerizations and correlates this aspect of network structure with reaction kinetic parameters and macroscopic volumetric shrinkage. Photopolymerization kinetics was followed in real-time by a near-infrared (NIR) spectroscopic technique, viscosity was assessed with a viscometer, volumetric shrinkage was followed with a linometer, free volume formation was determined by positron annihilation lifetime spectroscopy (PALS) and the sol-gel composition was determined by extraction with dichloromethane followed by (1)H NMR analysis. Results show that, as expected, volumetric shrinkage increases with TEGDMA concentration and monomer conversion. Extraction/(1)H NMR studies show increasing participation of the more flexible TEGDMA towards the limiting stages of conversion/crosslinking development. As the conversion progresses, either based on longer irradiation times or greater TEGDMA concentrations, the network becomes more dense, which is evidenced by the decrease in free volume and weight loss after extraction in these situations. For the same composition (BisGMA/TEGDMA 60-40 mol%) light-cured for increasing periods of time (from 10 to 600 s), free volume decreased and volumetric shrinkage increased, in a linear relationship with conversion. However, the correlation between free volume and macroscopic volumetric shrinkage was shown to be rather complex for variable compositions exposed for the same time (600 s). The addition of TEGDMA decreases free-volume up to 40 mol% (due to increased conversion), but above that concentration, in spite of the increase in conversion/crosslinking, free volume pore size increases due to the high concentration of the more flexible monomer. In those cases, the increase in volumetric shrinkage was due to higher functional group concentration, in spite of the greater free volume. Therefore, through the application of the PALS model, this study elucidates the network formation in dimethacrylates commonly used in dental materials. (C) 2010 Elsevier Ltd. All rights reserved.

Influence of BisGMA, TEGDMA, and BisEMA contents on viscosity, conversion, and flexural strength of experimental resins and composites

Different monomer structures lead to different physical and mechanical properties for both the monomers and the polymers. The objective of this study was to determine the influence of the bisphenylglycidyl dimethacrylate (BisGMA) concentration (33, 50 or 66 mol%) and the co-monomer content [triethylene glycol dimethacrylate (TEGDMA), ethoxylated bisphenol-A dimethacrylate (BisEMA), or both in equal parts] on viscosity (eta), degree of conversion (DC), and flexural strength (FS). eta was measured using a viscometer, DC was obtained by Fourier transfer Raman (FT-Raman) spectroscopy, and FS was determined by three-point bending. At 50 and 66% BisGMA, increases in eta were observed following the partial and total substitution of TEGDMA by BisEMA. For 33% BisGMA, eta increased significantly only when no TEGDMA was present. The DC was influenced by BisGMA content and co-monomer type. Mixtures containing 66% BisGMA showed a lower DC compared with mixtures containing other concentrations of BisGMA. The BisEMA mixtures had a lower DC compared with the TEGDMA mixtures. The FS was influenced by co-monomer content only. BisEMA mixtures presented a statistically lower FS, followed by TEGDMA + BisEMA mixtures, and then by TEGDMA mixtures. Partial or total replacement of TEGDMA by BisEMA increased eta, which was associated with the observed decreases in DC and FS. Although the BisGMA content influenced the DC, it did not affect the FS results.