Connecting Clinical Capacity and Intervention Sustainability in Resource-Variable Pediatric Oncology Centers in Latin America.

Clinical capacity for sustainability, or the clinical resources needed to sustain an evidence-based practice, represent proximal determinants that contribute to intervention sustainment. We examine the relationship between clinical capacity for sustainability and sustainment of PEWS, an evidence-based intervention to improve outcomes for pediatric oncology patients in resource-variable hospitals. We conducted a cross-sectional survey among Latin American pediatric oncology centers participating in Proyecto Escala de Valoración de Alerta Temprana (EVAT), an improvement collaborative to implement Pediatric Early Warning Systems (PEWS). Hospitals were eligible if they had completed PEWS implementation. Clinicians were eligible to participate if they were involved in PEWS implementation or used PEWS in clinical work. The Spanish language survey consisted of 56 close and open-ended questions about the respondent, hospital, participants' assessment of clinical capacity to sustain PEWS using the clinical sustainability assessment tool (CSAT), and perceptions about PEWS and its use as an intervention. Results were analyzed using a multi-level modeling approach to examine the relationship between individual, hospital, intervention, and clinical capacity determinants to PEWS sustainment. A total of 797 responses from 37 centers in 13 countries were included in the analysis. Eighty-seven percent of participants reported PEWS sustainment. After controlling for individual, hospital, and intervention factors, clinical capacity was significantly associated with PEWS sustainment (OR 3.27, p < .01). Marginal effects from the final model indicate that an increasing capacity score has a positive influence (11% for every additional CSAT point) of predicting PEWS sustainment. PEWS is a sustainable intervention and clinical capacity to sustain PEWS contributes meaningfully to PEWS sustainment.

3'-O-ß-d-glucopyranosyl-α,4,2',4',6'-pentahydroxy-dihydrochalcone, from Bark of Eysenhardtia polystachya Prevents Diabetic Nephropathy via Inhibiting Protein Glycation in STZ-Nicotinamide Induced Diabetic Mice.

Previous studies have shown that accumulation of advanced glycation end products (AGEs) can be the cause of diabetic nephropathy (DN) in diabetic patients. Dihydrochalcone 3'-O-ß-d-glucopyranosyl α,4,2',4',6'-pentahydroxy⁻dihydrochalcone (1) is a powerful antiglycation compound previously isolated from Eysenhardtia polystachya. The aim was to investigate whether (1) was able to protect against diabetic nephropathy in streptozotocin (STZ)-induced diabetic mice, which displayed renal dysfunction markers such as body weight, creatinine, uric acid, serum urea, total urinary protein, and urea nitrogen in the blood (BUN). In addition, pathological changes were evaluated including glycated hemoglobin (HbA1c), advanced glycation end products (AGEs) in the kidney, as well as in circulation level and pro-inflammatory markers ICAM-1 levels in diabetic mice. After 5 weeks, these elevated markers of dihydrochalcone treatment (25, 50 and 100 mg/kg) were significantly (p < 0.05) attenuated. In addition, they ameliorate the indices of renal inflammation as indicated by ICAM-1 markers. The kidney and circulatory AGEs levels in diabetic mice were significantly (p < 0.05) attenuated by (1) treatment. Histological analysis of kidney tissues showed an important recovery in its structure compared with the diabetic group. It was found that the compound (1) attenuated the renal damage in diabetic mice by inhibiting AGEs formation.

Diced and crushed cartilage plus autologous fibrin matrix obtained by a simple process for dorsal augmentation of the Mestizo nose.

Several alternatives can be used for nasal dorsum augmentation. We report the use of crushed diced cartilage embedded in an autologous fibrin matrix. This construct is placed on the nasal dorsum and is gently molded according to the characteristics of each patient. Rhinoplasty and nasal dorsum augmentation were performed in 45 patients with Mestizo characteristics after a complete medical history and development of a surgical plan. A crushed diced cartilage autologous graft and an autologous fibrin matrix from peripheral blood processed using the Choukroun method was used. Pre- and postoperative photographs were taken at short- and long-term follow-up. Two separate variables were evaluated: reabsorption and irregularities. Three plastic surgeons evaluated the results, using a Likert scale: the first variable was considered very excellent in 88.9%, very good in 6.7%, good in 4.4% with no poor or very poor results. In the second variable, results were excellent in 88.9%, very good in 4.4%, good in 3.4%, and poor in 3.3% with no very poor results. Our patients carry a volume with an aesthetically pleasing contour and form with no changes over a mean follow-up period of 4 years. Long-term effectiveness continues to be the main topic of discussion; however, this method can be considered an alternative not only to augment but also to smoothen irregularities of the nasal dorsum. We used a simple method with good and stable long-term clinical results.

A comparative study of physical and chemical processes for removal of biomass in biofilters.

After 6 months of operation a long-term biofilter was stopped for two weeks and then it was started up again for a second experimental period of almost 1.3 years, with high toluene loads and submitted to several physical and chemical treatments in order to remove excess biomass that could affect the reactor's performance due to clogging, whose main effect is a high pressure drop. Elimination capacity and removal efficiency were determined after each treatment. The methods applied were: filling with water and draining, backwashing, and air sparging. Different flows and temperatures (20, 30, 45 and 60 °C) were applied, either with distilled water or with different chemicals in aqueous solutions. Treatments with chemicals caused a decrease of the biofilter performance, requiring periods of 1 to 2 weeks to recover previous values. The results indicate that air sparging with pure distilled water as well as with solutions of NaOH (0.01% w/v) and NaOCl (0.01% w/v) were the treatments that removed more biomass, working either at 20, 30 or 45 °C and at relatively low flow rates (below 320 L h(-1)), but with a high biodegradation inhibition after the treatments. Dry biomass (g VS) content was determined at three different heights of the biofilter in order to carry out each experiment under the same conditions. The same amount of dry biomass when applying a treatment was established so it could be considered that the biofilm conditions were identical. Wet biomass was used as a control of the biofilter's water content during treatments. Several batch assays were performed to support and quantify the observed inhibitory effects of the different chemicals and temperatures applied.

Porous hydroxyapatite and gelatin/hydroxyapatite microspheres obtained by calcium phosphate cement emulsion.

Hydroxyapatite and hybrid gelatine/hydroxyapatite microspheres were obtained through a water in oil emulsion of a calcium phosphate cement (CPC). The setting reaction of the CPC, in this case the hydrolysis of α-tricalcium phosphate, was responsible for the consolidation of the microspheres. After the setting reaction, the microspheres consisted of an entangled network of hydroxyapatite crystals, with a high porosity and pore sizes ranging between 0.5 and 5 µm. The size of the microspheres was tailored by controlling the viscosity of the hydrophobic phase, the rotation speed, and the initial powder size of the CPC. The incorporation of gelatin increased the sphericity of the microspheres, as well as their size and size dispersion. To assess the feasibility of using the microspheres as cell microcarriers, Saos-2 cells were cultured on the microspheres. Fluorescent staining, SEM studies, and LDH quantification showed that the microspheres were able to sustain cell growth. Cell adhesion and proliferation was significantly improved in the hybrid gelatin/hydroxyapatite microspheres as compared to the hydroxyapatite ones.

Non-dermatophyte moulds as skin and nail foot mycosis agents: Phoma herbarum, Chaetomium globosum and Microascus cinereus.

The increased prevalence of dermatomycoses along with the wide range of organisms now recognized as potential pathogens needs accurate laboratory isolation and identification of the aetiological agents. In this report three cases of foot dermatomycoses due to filamentous fungi commonly present in the environment with ubiquitous distribution are described in immunocompetent subjects. Skin and nail samples were collected, suspended in 20% KOH solution, examined under a light microscope and cultured in Mycobiotic agar and Sabouraud dextrose agar containing chloramphenicol to detect fungal growth. Phoma herbarum, Chaetomium globosum, and Microascus cinereus were isolated and identified.

Discerning the role of topography and ion exchange in cell response of bioactive tissue engineering scaffolds.

Surface topography is known to have an influence on osteoblast activity. However, in the case of bioactive materials, topographical changes can affect also ion exchange properties. This makes the problem more complex, since it is often difficult to separate the strictly topographical effects from the effects of ionic fluctuations in the medium. The scope of this paper is to analyze the simultaneous effect of topography and topography-mediated ion exchange on the initial cellular behavior of osteoblastic-like cells cultured on bioactive tissue engineering substrates. Two apatitic substrates with identical chemical composition but different micro/nanostructural features were obtained by low-temperature setting of a calcium phosphate cement. MG63 osteoblastic-like cells were cultured either in direct contact with the substrates or with their extracts. A strong and permanent decrease of calcium concentration in the culture medium, dependent on substrate topography, was detected. A major effect of the substrate microstructure on cell proliferation was observed, explained in part by the topography-mediated ion exchange, but not specifically by the ionic Ca(2+) fluctuations. Cell differentiation was strongly enhanced when cells were cultured on the finer substrate. This effect was not explained by the chemical modification of the medium, but rather suggested a strictly topographical effect.

Mechanical and structural characterisation of completely degradable polylactic acid/calcium phosphate glass scaffolds.

This study involves the mechanical and structural characterisation of completely degradable scaffolds for tissue engineering applications. The scaffolds are a composite of polylactic acid (PLA) and a soluble calcium phosphate glass, and are thus completely degradable. A factorial experimental design was applied to optimise scaffold composition prior to simultaneous microtomography and micromechanical testing. Synchrotron X-ray microtomography combined with in situ micromechanical testing was performed to obtain three-dimensional (3D) images of the scaffolds under compression. The 3D reconstruction was converted into a finite element mesh which was validated by simulating a compression test and comparing it with experimental results. The experimental design reveals that larger glass particle and pore sizes reduce the stiffness of the scaffolds, and that the porosity is largely unaffected by changes in pore sizes or glass weight content. The porosity ranges between 93% and 96.5%, and the stiffness ranges between 50 and 200 kPa. X-ray projections show a homogeneous distribution of the glass particles within the PLA matrix, and illustrate pore-wall breakage under strain. The 3D reconstructions are used qualitatively to visualise the distribution of the phases of the composite material, and to follow pore deformation under compression. Quantitatively, scaffold porosity, pore interconnectivity and surface/volume ratios have been calculated. Finite element analysis revealed the stress and strain distribution in the scaffold under compression, and could be used in the future to characterise the mechanical properties of the scaffolds.

In vivo evaluation of an injectable Macroporous Calcium Phosphate Cement.

Although Calcium Phosphate Cements (CPC) are highly biocompatible and osteconductive materials, its resorption rate still remains too slow for some applications. In this work the introduction of Macroporosity in an injectable CPC is evaluated as a way to accelerate resorption and to increase bone ingrowth. A Macroporous and a standard CPC were injected just after preparation in a defect drilled in rabbit femur for their in vivo evaluation. The foaming agent used was Albumen, which gave up to a 75% porosity. Sodium Alginate was added to promote the cohesion of the foamed paste after implantation. In the case of the Macroporous Cement, bone growth and neovascularisation was observed inside the pores of the material, not only at the margins of the cement but also in some central pores. After 12 weeks of implantation, the residual material volume of the Macroporous Cement was approximately 35% of the initial value, whereas only the outer layers of non-Macroporous CPC were resorbed, being the residual material volume close to 100%. The higher resorption rate was due to the higher surface contact with body fluids which increased the dissolution rate, and to the enhancement of the cellular activity.

Factors affecting the structure and properties of an injectable self-setting calcium phosphate foam.

One of the main challenges in the investigation on calcium phosphate cements (CPC) lies in the introduction of macroporosity, without loosing the self-setting ability and injectability, characteristic of the cement-type materials. The benefits of macroporosity are related to the enhancement of bone regeneration mechanisms, such as angiogenesis and tissue ingrowth. In this work, the feasibility to obtain self-setting injectable macroporous hydroxyapatite foams by the incorporation of a protein-based foaming agent to a CPC is demonstrated. Albumen is combined with an alpha-tricalcium phosphate [Ca3(PO4)2, alpha-TCP] paste, which hydrolyzes to a calcium deficient hydroxyapatite during the setting reaction. A systematic study is presented, where the effect of different processing parameters is analyzed in terms of porosity, setting properties, injectability, and compressive strength. Self-setting foams with porosities up to 70%, which maintain their porous structure after injection, are obtained. These injectable foams can be used both for direct in vivo applications and for the fabrication of low temperature tissue engineering scaffolds.

New macroporous calcium phosphate glass ceramic for guided bone regeneration.

This work describes a method to obtain macroporous resorbable glass and glass ceramic scaffolds with controlled biodegradability for tissue engineering applications. The constructs consisted of glass and glass ceramics in the system P(2)O(5)-CaO-Na(2)O-TiO(2) and they were prepared by foaming a slurry of glass particles by addition of a H(2)O(2) solution, and subsequent sintering of the porous structures obtained. Different thermal treatments were applied to control the degree of devitrification of the glass. The resultant materials showed a porosity percentage between 40% and 55% with a wide variety of pores ranging from 20 to 500 microm in diameter as determined by SEM and Image Analysis. The resulting constructs were predominantly formed by a vitreous phase, although small amounts of calcium metaphosphate and pyrophosphates were detected by X-ray diffraction and Raman spectroscopy after the sintering process. The biological response was also evaluated by means of the MTT test, the material showed a non-cytotoxic effect.