Acupuncture Increases The Diameter And Reorganisation Of Collagen Fibrils During Rat Tendon Healing.

Our previous study showed that electroacupuncture (EA) increases the concentration and reorganisation of collagen in a rat model of tendon healing. However, the ultrastructure of collagen fibrils after acupuncture is unknown. To assess the effect of acupuncture protocols on the ultrastructure of collagen fibrils during tendon healing. Sixty-four rats were divided into the following groups: non-tenotomised (normal group), tenotomised (teno group), tenotomised and subjected to manual acupuncture at ST36 (ST36 group), BL57 (BL57 group) and ST36+BL57 (SB group) and EA at ST36+BL57 (EA group). The mass-average diameter (MAD) and the reorganisation of collagen fibril diameters were determined during the three phases of tendon healing (at 7, 14 and 21 days). The MAD increased during the three phases of healing in the SB group. In the EA group, MAD increased initially but was reduced at day 21. The reorganisation of collagen fibrils was improved in the EA and SB groups at days 14 and 21, respectively. EA at day 21 appeared to reduce the reorganisation. These results indicate that the use of EA up to day 14 and manual acupuncture at ST36+BL57 up to day 21 improve the ultrastructure of collagen fibrils, indicating strengthening of the tendon structure. These data suggest a potential role for acupuncture in rehabilitation protocols.

Fiber average size and distribution dependence on the electrospinning parameters of poly(vinylidene fluoride trifluoroethylene)) membranes for biomedical applications

Poly(vinylidene fluoride-trifluoethylene) electrospun membranes were obtained from a blend of dimethylformamide (DMF) and methylethylketone (MEK) solvents. The inclusion of the MEK to the solvent system promotes a faster solvent evaporation allowing complete polymer crystallization during the jet travelling between the tip and the grounded collector. Several processing parameters were systematically changed to study their influence on fiber dimensions. Applied voltage and inner needle diameter do not have large influence on the electrospun fiber average diameter but in the fiber diameter distribution. On the other hand, the increase of the distance between the needle tip to collector results in fibers with larger average diameter. Independently on the processing conditions, all mats are produced in the electroactive phase of the polymer. Further, MC-3T3-E1cell adhesion was not inhibited by the fiber mats preparation, indicating their potential use for biomedical applications.

Low-density lipoprotein particle diameter and mortality: the Ludwigshafen Risk and Cardiovascular Health Study.

AIMS The aim of the study was to examine whether differences in average diameter of low-density lipoprotein (LDL) particles were associated with total and cardiovascular mortality. METHODS AND RESULTS We studied 1643 subjects referred to coronary angiography, who did not receive lipid-lowering drugs. During a median follow-up of 9.9 years, 398 patients died, of these 246 from cardiovascular causes. We calculated average particle diameters of LDL from the composition of LDL obtained by β-quantification. When LDL with intermediate average diameters (16.5-16.8 nm) were used as reference category, the hazard ratios (HRs) adjusted for cardiovascular risk factors for death from any cause were 1.71 (95% CI: 1.31-2.25) and 1.24 (95% CI: 0.95-1.63) in patients with large (>16.8 nm) or small LDL (<16.5 nm), respectively. Adjusted HRs for death from cardiovascular causes were 1.89 (95% CI: 1.32-2.70) and 1.54 (95% CI: 1.06-2.12) in patients with large or small LDL, respectively. Patients with large LDL had higher concentrations of the inflammatory markers interleukin (IL)-6 and C-reactive protein than patients with small or intermediate LDL. Equilibrium density gradient ultracentrifugation revealed characteristic and distinct profiles of LDL particles in persons with large (approximately even distribution of intermediate-density lipoproteins and LDL-1 through LDL-6) intermediate (peak concentration at LDL-4) or small (peak concentration at LDL-6) average LDL particle diameters. CONCLUSIONS Calculated LDL particle diameters identify patients with different profiles of LDL subfractions. Both large and small LDL diameters are independently associated with increased risk mortality of all causes and, more so, due to cardiovascular causes compared with LDL of intermediate size.

Didanosine-loaded Chitosan Microspheres Optimized By Surface-response Methodology: A Modified Maximum Likelihood Classification" Approach Formulation For Reverse Transcriptase Inhibitors."

Didanosine-loaded chitosan microspheres were developed applying a surface-response methodology and using a modified Maximum Likelihood Classification. The operational conditions were optimized with the aim of maintaining the active form of didanosine (ddI), which is sensitive to acid pH, and to develop a modified and mucoadhesive formulation. The loading of the drug within the chitosan microspheres was carried out by ionotropic gelation technique with sodium tripolyphosphate (TPP) as cross-linking agent and magnesium hydroxide (Mg(OH)2) to assure the stability of ddI. The optimization conditions were set using a surface-response methodology and applying the Maximum Likelihood Classification, where the initial chitosan concentration, TPP and ddI concentration were set as the independent variables. The maximum ddI-loaded in microspheres (i.e. 1433mg of ddI/g chitosan), was obtained with 2% (w/v) chitosan and 10% TPP. The microspheres depicted an average diameter of 11.42μm and ddI was gradually released during 2h in simulated enteric fluid.

Production Of Microparticles With Gelatin And Chitosan.

In the past few decades, the textile industry has significantly increased investment in research to develop functional fabrics, with a special focus on those aggregating values. Such fabrics can exploit microparticles inferior to 100 μm, such as those made by complex coacervation in their creation. The antimicrobial properties of chitosan can be attributed to these microparticles. Developing particles with uniform structure and properties would facilitate the control for the eventual release of the core material. Thus, a complex coacervation between gelatin and chitosan was studied, and the optimal conditions were replicated in the encapsulation of limonene. Spherical particles formed had an average diameter (D3,2) of 30 μm and were prepared with 89.7% efficiency. Cross-linking of these microparticles using glutaraldehyde and tripolyphosphate was carried out before spray drying. After drying, microparticles cross-linked with glutaraldehyde were oxidized and clustered and those that were cross-linked with tripolyphosphate resisted drying and presented a high yield.

Desenvolvimento e caracterização de nanocápsulas de poli (L-lactídeo) contendo benzocaína

In this paper we describe the preparation poly (L-lactide) (PLA) nanocapsules as a drug delivery system for the local anesthetic benzocaine. The characterization and in vitro release properties of the system were investigated. The characterization results showed a polydispersity index of 0.14, an average diameter of 190.1± 3 nm, zeta potential of -38.5 mV and an entrapment efficiency of 73%. The release profile of Benzocaine loaded in PLA nanocapsules showed a significant different behavior than that of the pure anesthetic in solution. This study is important to characterize a drug release system using benzocaine for application in pain treatment.

Produção de micropartículas de alginato contendo Flavobacterium columnare inativada pelo método de emulsão para vacinação de peixes por via oral

Alginate microparticles were prepared by an emulsion method aiming oral controlled release of antigens to fish. The effects of emulsification temperature and impeller type on particle morphology, average diameter, and size distribution were evaluated. Microparticles contaning formalin-killed Flavobacterium columnare cells (a model antigen) were prepared and characterized regarding bacterial release and particle stability when exposed to Nile tilapia (Oreochromis niloticus) typical gastrointestinal conditions. This methodology allowed the production of microparticles containing up to 14.3 g/L of bacterin, stable at a pH range from 2.0 to 9.0 for 12 h and smaller than 35 μm.

O Complexo Vegetacional da Zona Litorânea no Ceará: Pecém, São Gonçalo do Amarante

Due to its geographical location, the northeastern Coast of Brazil (Litoral Setentrional do Nordeste - LSN) is a hotter and drier climate than the eastern coast. In addition, because of its proximity to caatinga and cerrado, the LSN contains species from these vegetation biomes and from the restinga on the coast, which comprise different plant formations and creates a vegetation complex. Despite the great importance of this ecotone, there are few studies about its flora. The objective of this work was to contribute to what is known about the floristic and phytosociological composition of this region. We made a floristic survey in the area (between 2007 and 2011), consulted herbaria data from the region and made a phytosociological study in a stretch of coastal semideciduous forest (mata de tabuleiro). The study recorded 382 plant species from 96 families. In the phytosociological survey (0.32 ha) we recorded 2,970 individuals and 52 species. The most abundant plants surveyed were the trees Manilkara triflora, Chamaecrista ensiformis and Guapira nitida and the shrubs Cordiera sessilis and Maytenus erythroxyla (average height 3.8 m, average diameter 6.2 cm, basal area 39.28 m²/ha). The local flora includes floristic elements of caatinga, cerrado and restinga, corroborating the idea that the plant community of the coastal region of Ceará has an ecotonal nature.

Supramolecular assemblies of rifampicin and cationic bilayers: preparation, characterization and micobactericidal activity

Background: Cationic bilayers based on the inexpensive synthetic lipid dioctadecyldimethylammonium bromide (DODAB) have been useful as carriers for drug delivery, immunoadjuvants for vaccines and active antimicrobial agents. Methods: Rifampicin (RIF) or isoniazid (ISO) interacted with DODAB bilayer fragments (BF) or large vesicles (LV). Dispersions were evaluated by dynamic light-scattering for zeta-average diameter (Dz) and zeta-potential (zeta) analysis; dialysis for determination of drug entrapment efficiency; plating and CFU counting for determination of cell viability of Mycobacterium smegmatis or tuberculosis, minimal bactericidal concentration (MBC) and synergism index for DODAB/drug combinations. Results: DODAB alone killed micobacteria over a range of micromolar concentrations. RIF aggregates in water solution were solubilised by DODAB BF. RIF was incorporated in DODAB bilayers at high percentiles in contrast to the leaky behavior of ISO. Combination DODAB/RIF yielded MBCs of 2/2 and 4/0.007 mu g/mL against Mycobacterium smegmatis or Mycobacterium tuberculosis, respectively. Synergism indexes equal to 0.5 or 1.0, indicated synergism against the former and independent action, against the latter species. Conclusions: In vitro, DODAB acted effectively both as micobactericidal agent and carrier for rifampicin. The novel assemblies at reduced doses may become valuable against tuberculosis.

Polydimethylsiloxane: a new contrast material for localization of occult breast lesions

Background. The radioguided localization of occult breast lesions (ROLL) technique often utilizes iodinated radiographic contrast to assure that the local injection of (99m)Tc-MAA corresponds to the location of the lesion under investigation. However, for this application, this contrast has several shortcomings. The objective of this study was to evaluate the safety, effectiveness and technical feasibility of the use of polydimethylsiloxane (PDMS) as radiological contrast and tissue marker in ROLL. Materials and methods. The safety assessment was performed by the acute toxicity study in Wistar rats (n = 50). The radiological analysis of breast tissue (n = 32) from patients undergoing reductive mammoplasty was used to verify the effectiveness of PDMS as contrast media. The technical feasibility was evaluated through the scintigraphic and histologic analysis. Results. We found no toxic effects of PDMS for this use during the observational period. It has been demonstrated in human breast tissue that the average diameter of the tissue marked by PDMS was lower than when marked by the contrast medium (p <0.001). PDMS did not interfere with the scintigraphic uptake (p = 0.528) and there was no injury in histological processing of samples. Conclusions. This study demonstrated not only the superiority of PDMS as radiological contrast in relation to the iodinated contrast, but also the technical feasibility for the same applicability in the ROLL.

Investigation of a magnetohyperthermia system efficacy

This study reports on the successful use of magnetic albumin nanosphere (MAN) with in vivo magnetohyperthermia (MHT) in a mouse Ehrlich tumor. Maghemite nanoparticles (8.9 nm average diameter) were encapsulated within MAN (73.0 nm average diameter). Ehrlich tumor obtained after implantation of tumor cells in the subcutaneous tissue of mice was used as a model throughout this study. MHT was performed with MAN (40 mu L) containing 1.2 x 10(15) particle/mL and 40 Oe amplitude ac magnetic field oscillating at 1 MHz. Animals not treated, treated with MAN, or exposed to the ac field were used as controls. Histopathological analysis was carried out after 2, 5, or 11 days of tumor implantation. We found that the MHT most efficient condition was obtained while applying the ac field protocol twice a day during three consecutive days. Further, in this ac field-treated group no proliferation cells were detected. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3559498]

Poly(aniline)/poly(methylmethacrylate) films obtained from waterborne latex nanoparticles

This paper presents the characterization of poly(aniline) (PANI) and poly(methyl methacrylate) (PMMA) coatings obtained by mixing PANI with PMMA aqueous dispersions (latex particles). These dispersions were characterized by using dynamic light scattering for sizing, zeta-potential analysis and thermal analysis. PMMA and PANI/PMMA dispersions show negative charged particles with zeta potential greater than |40| mV, a zeta-average diameter of 64 nm for pure PMMA and a bi-modal particle-size distribution centered at 45 and 120 nm for a mixture with 25% w/w of PANI. Films obtained by casting were characterized by using scanning electron microscopy and they show a conductivity increase upon PANI content reaching a value of 1 mS cm(-1) for a film with 25% w/w of PANI. In addition, Raman spectroscopy have shown the presence of the conducting form of PANI in the films and cyclic voltammetry experiments corroborated that they are electroactive in both acid and neutral solutions.

Manufacture of ceramic membranes for application in demulsification process for cross-flow microfiltration

This paper describes the manufacture of tubular ceramic membranes and the study of their performance in the demulsification of soybean oil/water emulsions. The membranes were made by iso-static pressing method and micro and macro structurally characterized by SEM, porosimetry by mercury intrusion and determination of apparent density and porosity. The microfiltration tests were realized on an experimental workbench, and fluid dynamic parameters, such as transmembrane flux and pressure were used to evaluate the process relative to the oil phase concentration (analysed by TOC measurements) in the permeate. The results showed that the membrane with pores` average diameter of 1.36 mu m achieved higher transmembrane flux than the membrane with pores` average diameter of 0.8 mu m. The volume of open pores (responsible for the permeation) was predominant in the total porosity, which was higher than 50% for all tested membranes. Concerning demulsification, the monolayer membranes were efficacious, as the rejection coefficient was higher than 99%.

Characterization of micro-bubble size distribution and flow configuration in DAF contact zone by a non-intrusive image analysis system and tracer tests

This paper aims to investigate the influence of some dissolved air flotation (DAF) process variables (specifically: the hydraulic detention time in the contact zone and the supplied dissolved air concentration) and the pH values, as pretreatment chemical variables, on the micro-bubble size distribution (BSD) in a DAF contact zone. This work was carried out in a pilot plant where bubbles were measured by an appropriate non-intrusive image acquisition system. The results show that the obtained diameter ranges were in agreement with values reported in the literature (10-100mm), quite independently of the investigated conditions. The linear average diameter varied from 20 to 30mm, or equivalently, the Sauter (d(3,2)) diameter varied from 40 to 50mm. In all investigated conditions, D(50) was between 75% and 95%. The BSD might present different profile (with a bimodal curve trend), however, when analyzing the volumetric frequency distribution (in some cases with the appearance of peaks in diameters ranging from 90-100mm). Regarding volumetric frequency analysis, all the investigated parameters can modify the BSD in DAF contact zone after the release point, thus potentially causing changes in DAF kinetics. This finding prompts further research in order to verify the effect of these BSD changes on solid particle removal efficiency by DAF.

In-Line Monitoring of Particle Size during Emulsion Polymerization under Different Operational Conditions using NIR Spectroscopy

In the present work, the sensitivity of NIR spectroscopy toward the evolution of particle size was studied during emulsion homopolymerization of styrene (Sty) and emulsion copolymerization of vinyl acetate-butyl acrylate conducted in a semibatch stirred tank and a tubular pulsed sieve plate reactor, respectively. All NIR spectra were collected online with a transflectance probe immersed into the reaction medium. The spectral range used for the NIR monitoring was from 9 500 to 13 000 cm(-1), where the absorbance of the chemical components present is minimal and the changes in the NIR spectrum can be ascribed to the effects of light scattering by the polymer particles. Off-line measurements of the average diameter of the polymer particles by DLS were used as reference values for the development of the multi-variate NIR calibration models based on partial least squares. Results indicated that, in the spectral range studied, it is possible to monitor the evolution of the average size of the polymer particles during emulsion polymerization reactions. The inclusion of an additional spectral range, from 5 701 to 6 447 cm(-1), containing information on absorbances (""chemical information"") in the calibration models was also evaluated.