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Advanced oxidation processes (AOP), using semiconductor (SC) and hydroxyapatite (HA) composites, are promising due to the synergy of photocatalytic and adsorption properties. Still, dye removal efficiency of composites based on HA-SC remains low, because most of the research reported consider single SC materials. In this work, nanocrystalline xerogels of titanium oxide (TiO2) with copper oxide (CuO) and HA were synthesized by the sol-gel process. HA was obtained by the precipitation method without heat treatment and calcined in the range of 200-1000 °C. TiO2 and copper precursors were added to a sol containing HA in a 12:1 mol ratio, obtaining HA-TiO2 and HA-CuO-TiO2 nanomaterials. The xerogels were characterized by X-ray diffraction, scanning electron microscopy, emission field scanning electron microscopy and photoresponse. Their performance in the photocatalytic discoloration of an aqueous solution acid yellow dye 36 (AY36) was evaluated, using visible and UV light. The best discoloration was achieved with HA-CuO-TiO2 xerogels with HA calcined at 600 °C, showing a degradation kinetic constant of 0.24 min-1. In contrast, HA-TiO2 materials showed little or no photocatalytic activity, but strong dye adsorption/desorption. The thermal treatment of HA determines the filament-like morphology and degree of compaction of the nanomaterials, which are relevant in the crystallite size and sensitization of the SC matrix. Further studies must address the surface chemistry and rectifying properties of the best SC composite to have a more complete understanding of the mechanisms involved.

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INTRODUCTION: Neuromyelitis optica (NMO) or Devic's disease is an autoimmune, inflammatory and demyelinating central nervous system disorder that affects mainly to optic nerve and spinal cord. Recent advances have substantially permitted to expand the knowledge about this entity. AIM: To present a clinical update on the current understanding of the nature, progression, diagnosis and treatment of NMO. DEVELOPMENT: Due to its demyelinating nature and its recurrent behavior in most cases, NMO was first considered a form of multiple sclerosis (MS). However, recent findings have led to the conclusion that NMO is a distinct disorder, presenting important immunopathological, clinical, prognostic and therapeutic differences from MS. Fundamental in the under-standing of the disease was the recent discovery of antibodies directed against aquaporin-4 (anti-AQP4, also known as NMO-IgG), which are present in the majority of NMO cases clinically defined, and in a minority of patients with MS. Despite the knowledge on its immunopathogenesis and advances in diagnosis, the treatment of NMO is still challenging. CONCLUSION: NMO is a demyelinating disease different from MS. Current diagnostic criteria have been enriched with the recent description of the humoral disorder underlying NMO. However, current treatment options for NMO are far from being ideal.

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INTRODUCTION: Stress Urinary Incontinence (SUI) may be managed by transobturator approach. We developed a three-dimensional model, for understanding the surgical anatomy and manual training as well, in order to reduce the learning curve for pelvic surgeries. OBJECTIVE: To demonstrate in synthetic models, the anatomical basis for the management of SUI and cystocele. METHOD: The anatomical model includes: pelvic bones, the main layers of the pelvic muscles, ligaments and fascias. The surgical devices were transobturator needles, synthetic slings and meshes for anterior vaginal wall repair. The workshop was carried out with an anatomical overview and hands-on training in this tridimentional models and finally surgery in animals. At the end, a questionnaire was applied to verify the impact of this tool in the learning process and trainee satisfaction. RESULTS: As far as the anatomical concept, 90% (n=72) of the participants classified this model as very good and 10% (n=8) as good. As a tool for understanding the tridimentional pelvic floor anatomy applied to transobturator procedures there were 100% of approval. CONCLUSIONS: This synthetic model allows for understanding the pelvic floor tridimentional anatomy and surgical procedures as well. Further skill is got in the animal model reducing the learning curve for transobturator procedures.

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The excitation spectra and the structural properties of highly hydroxylated C(60)(OH)(x) fullerenes (so-called fullerenols) are analyzed by comparing optical absorption experiments on dilute fullerenol-water solutions with semiempirical and density functional theory electronic structure calculations. The optical spectrum of fullerenol molecules with 24-28 OH attached to the carbon surface is characterized by the existence of broad bands with reduced intensities near the ultraviolet region (below approximately 500 nm) together with a complete absence of optical transitions in the visible part of the spectra, contrasting with the intense absorption observed in C(60) solutions. Our theoretical calculations of the absorption spectra, performed within the framework of the semiempirical Zerner intermediate neglect of diatomic differential overlap method [Reviews in Computational Chemistry II, edited by K. B. Lipkowitz and D. B. Boyd (VCH, Weinheim, 1991), Chap. 8, pp. 313-316] for various gas-phase-like C(60)(OH)(26) isomers, reveal that the excitation spectra of fullerenol molecules strongly depend on the degree of surface functionalization, the precise distribution of the OH groups on the carbon structure, and the presence of impurities in the samples. Interestingly, we have surprisingly found that low energy atomic configurations are obtained when the OH groups segregate on the C(60) surface forming molecular domains of different sizes. This patchy behavior for the hydroxyl molecules on the carbon surface leads in general to the formation of fullerene compounds with closed electronic shells, large highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps, and existence of an excitation spectrum that accounts for the main qualitative features observed in the experimental data.

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Biodegradable polymers have a variety of uses in basic and clinical research, as well as important therapeutic applications. The most commonly used are poly (lactic acid), poly (glycolic acid) and their copolymer, poly (L-lactic-co-glycolic acid) or PLGA. The incorporation of a plasticizer into a polymer can be used to obtain a product with specific properties. In this work, we examined the influence of a plasticizer (triethylcitrate) on the properties of PLGA membrane implants for human clinical uses. Membranes with and without plasticizer were dense and compact and contained no pores. The incorporation of 7% plasticizer enhanced the degradation the polymer when compared to polymer without plasticizer. In membranes without plasticizer, the initiation of degradation was very slow and was seen only 60 days after implantation, should allow the use of this material in the repair of damage tissue. In both cases, macroscopic analysis showed that there was no adhesion of the membrane to capsule fibrous, and this adversely affected preservation of the polymer. With time, the adherence of the polymer to surrounding tissue increased. Overall there was little degradation of membranes without plasticizer compared to those containing plasticizer.

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The prevalence of urinary incontinence is around 20% of healthy middle-aged women. Incontinence causes a negative impact on the quality of life and sexuality. From August 2002 to January 2004, 30 patients (mean age 43 years) with stress urinary incontinence (59%), overactive bladder (15%) and mixed incontinence (26%) answered the ICIQ-SF(International Consultation on Incontinence Questionnarie-Short Form) and FSFI (Female Sexual Function Index) questionnaires before and after treatment for urinary incontinence. The follow-up ranged from 12 to 53 months. Mean ICIQ score was 17 and 7 before and after treatment respectivelly (p<0,001). Overactive bladder showed the worst scores in all domains. The patients who underwent surgery increased their scores of desire (p=0,02), satisfaction (p=0,05) and total score (p=0,02). Thirteen patients which ICIQ was zero increased: desire (p<0,01), satisfaction (p=0,05) and total score (p=0,01). Urinary incontinence significantly affects the quality of life. Therefore sexual evaluation in incontinence patients is recommended.

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The use of bioabsorbable polymers in (bio)medical applications has increased greatly in recent years, mainly because of their good bioreabsorption and biocompatibility. In this work, we examined the development of foreign body giant cells in intimate contact with porous membranes of poly L-lactic acid containing 7% of plasticizer triethylcitrate implanted in the backs of rats. The membranes were removed 2, 7, 14, 21, 28, 60, 90 and 180 days after implantation, along with a portion of the tissue around the implant. Histological analysis of the implant and tissue revealed the formation of a fibrous capsule from the seventh day of implantation onwards. Foreign body giant cells appeared from the seventh day and increased in number up to the twenty-eighth day and then up to the ninetieth day of implantation, remaining constant up to the end of the study onwards, and increased in number up to the ninetieth day after implantation and then remained constant. The number of nuclei in these cells increased from the seventh day of implantation up to the ninetieth day and then up to the end of the study.

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Poly(L-lactic acid) (PLLA) membranes containing 7% triethylcitrate plasticizer were implanted in the subcutaneous tissue of rats, and the cellular reaction was evaluated over a period of 2-180 days. The samples were processed for conventional transmission electron microscopy. Polymorphonuclear-type cells and a fibrin network were seen within membrane pores 2 days after implantation. In subsequent samples, there was cellular infiltration, which consisted mainly of fibroblasts, macrophages and multinuclear giant cells embedded in an abundant extracellular matrix containing a network of collagen fibers and blood vessels. At 90 and 180 days after implantation, a high density of voluminous phagocytic cells with a large number of endocytic polymer fragments within their cytoplasm was seen. These results show that PLLA membranes can support connective tissue proliferation and remodeling, which are important properties for successful bio-protheses.

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