Genome Sequence Resource of 'Candidatus Liberibacter asiaticus' strain 9PA From Brazil.

'Candidatus Liberibacter asiaticus', an unculturable α-proteobacterium, is associated with citrus huanglongbing (HLB), a devastating disease threatening citrus production in Brazil and worldwide. In this study, a draft whole-genome sequence of 'Ca. L. asiaticus' strain 9PA from a sweet orange (cultivar Pera) tree collected in São Paulo State, Brazil, is reported. The 9PA genome is 1,231,881 bp, including two prophages, with G+C content of 36.7%. This is the first report of a whole-genome sequence of 'Ca. L. asiaticus' from Brazil or South America. The 9PA genome sequence will enrich 'Ca. L. asiaticus' genome resources and facilitate HLB research and control in Brazil and the world.

A combined experimental and numerical approach to the assessment of floc settling velocity using fractal geometry.

Sedimentation processes are fundamental to solids/liquid separation in water and wastewater treatment, and therefore a robust understanding of the settlement characteristics of mass fractal aggregates (flocs) formed in the flocculation stage is fundamental to optimized settlement tank design and operation. However, the use of settling as a technique to determine aggregates' traits is limited by current understanding of permeability. In this paper, we combine experimental and numerical approaches to assess settling velocities of fractal aggregates. Using a non-intrusive in situ digital image-based method, three- and two-dimensional fractal dimensions were calculated for kaolin-based flocs. By considering shape and fractal dimension, the porosity, density and settling velocities of the flocs were calculated individually, and settling velocities compared with those of spheres of the same density using Stokes' law. Shape analysis shows that the settling velocities for fractal aggregates may be greater or less than those for perfect spheres. For example, fractal aggregates with floc fractal dimension, Df = 2.61, floc size, df > 320 µm and dp = 7.5 µm settle with lower velocities than those predicted by Stokes' law; whilst, for Df = 2.33, all aggregates of df > 70 µm and dp = 7.5 µm settled below the velocity calculated by Stokes' law for spheres. Conversely, fractal settling velocities were higher than spheres for all the range of sizes, when Df of 2.83 was simulated. The ratio of fractal aggregate to sphere settling velocity (the former being obtained from fractal porosity and density considerations), varied from 0.16 to 4.11 for aggregates in the range of 10 and 1,000 µm, primary particle size of 7.5 µm and a three-dimensional fractal dimension between 2.33 and 2.83. However, the ratio decreases to the range of 0.04-2.92 when primary particle size changes to 1.0 µm for the same fractal dimensions. Using the floc analysis technique developed here, the results demonstrate the difference in settlement behaviour between the approach developed here and the traditional Stokes' law approach using solid spheres. The technique and results demonstrate the improvements in understanding, and hence value to be derived, from an analysis based on fractal, rather than Euclidean, geometry when considering flocculation and subsequent clarification performance.

Direct and transdentinal biostimulatory effects of grape seed extract rich in proanthocyanidin on pulp cells.

AIM: To evaluate the potential biostimulatory effects of grape seed extract (GSE) on a primary culture of human pulp cells. METHODOLOGY: Human molars were used to obtain the primary pulp cell culture and 0.5-mm dentine discs. For GSE direct exposure, dose-response (0.0065-6.5%) and time response (1-60 min of contact) were examined. For transdentinal exposure, 0.65% of GSE was tested for 24 h. Cellular metabolism, nitric oxide and collagen production, and cell morphology alterations were assessed at periods of 24 and 72 h. After cell differentiation and direct exposure to GSE, the total protein production (TP), alkaline phosphatase activity (ALP) and formation of mineralization nodules (MN) were assessed. The results were analysed by parametric tests or non-parametric tests (α = 0.05). RESULTS: The lower concentration of GSE tested (0.0065%) was associated with an increase in cellular metabolism, a reduction in the production of nitric oxide and an increase in extracellular matrix synthesis (collagen). Distinct behaviours were observed for the different concentrations, without a reduction of cellular metabolism >10% compared with the control, either when applied directly or transdentinally. SEM revealed no significant change in cell morphology, except for the positive control (H2 O2 ). There was no difference in TP, ALP or MN between the control group and the group exposed to GSE. CONCLUSIONS: Treatment with grape seed extract, even at the highest concentration and longest period, caused neither direct nor transdentinal cytotoxic effects on human pulp cells. Grape seed extract components may play a biostimulatory role and protect dental pulp cells when in direct contact.

Photochemistry and desorption induced by X-rays in water rich astrophysical ice analogs: implications for the moon Enceladus and other frozen space environments.

Soft X-rays are an important agent for chemical processing in the Solar System and in the interstellar medium. The photolysis and photodesorption processes of H2O-rich ices triggered by soft X-rays was, experimentally, addressed in this paper. The experiments were performed at the Brazilian synchrotron facility LNLS/CNPEN employing broadband radiation (from 6 to 2000 eV; mainly soft X-rays and a small fraction of VUV) in solid samples at temperatures of 20 and 80 K. The icy samples were monitored by infrared spectroscopy. We determined the effective destruction cross section (in the order 10-18 cm2) as well as the formation cross section for the new species produced after the irradiation. Among them, we list OCN-, CO, CO3, CH3OH, H2O2, HCOO-, NH4 +, HCONH2 and CH3HCO, mostly formed in the experiment at 80 K. The chemical equilibrium stage was characterized and molecular abundances were quantified. In addition, we discuss a methodology to estimate the amount of unknown species in the ice produced by photolysis. The samples reach chemical equilibrium at fluences around 2-3 × 1018 cm-2. Timescales for reaching chemical equilibrium in space environments illuminated by X-rays were given, as well as the desorption yields induced by X-rays. The astrophysical implication on the surface chemistry and desorption processes at the moon Enceladus are provided.

Muscle thickness and echo-intensity changes of the quadriceps femoris muscle during a strength training program.

INTRODUCTION: Ultrasound (US) has an important role in musculoskeletal (MSK) evaluation, allowing the study of muscle morphology and function. Muscle thickness (MT) and muscle echo-intensity (EI) are two important parameters that may quantify muscle structural adaptations to a variety of stimuli. The aim was to explore the potential of quantitative US imaging for assessing the adaptations and responses of the muscle tissue to increased contractile activity using B-mode US. This study was centred on the quadriceps femoris muscle contractile activity on MT and EI. METHODS AND MATERIALS: Twenty-eight young male adults participated in the study, divided in a control group and two training groups performing concentric or eccentric strength training, respectively. The effect of a 15-week strength program was studied on MT and EI in several regions of the heads of the quadriceps femoris using B-mode US. All images acquisitions and measurements were done by the same experience sonographer. RESULTS: Strength training resulted in an increase of MT at all muscles and sites (p < 0.05), except the VM. Strength training failed in changing EI in most of the quadriceps femoris, except in the VI and some regions of the VL. No statistically significant differences were observed in our quantitative US parameters between concentric and eccentric training (p > 0.05). CONCLUSION: These results emphasise the value of MT as a quantifiable muscle US method for evaluating muscle adaptation to exercise training. However, the inconsistency of the EI values indicates that more studies are needed to develop it as an accurate diagnostic tool.

Acoustic radiation force impulse elastography of the eyes of brachycephalic dogs / Elastografia acoustic radiation force impulse dos olhos de cães braquicefálicos

Eyes from brachycephalic dogs were studied by acoustic radiation force impulse (ARFI) elastography to establish quantitative and qualitative reference values related to the shape and rigidity of some ocular structures. Eighty-four eyes from 42 adult brachycephalic dogs were included in this study. Animals were subjected to physical, laboratory, and ophthalmic examinations. Following confirmation of good health, the dogs were subjected to ultrasonography and ARFI elastography, emphasizing the optic nerve, ciliary body, and lens. On qualitative elastography, homogeneous characteristics were observed on the ciliary body and optic nerve. Aqueous and vitreous humors were visualized as mosaic-like images. Quantitative elastography showed the mean optic nerve shear wave velocity (SWV) was 1.01±0.27m/s, temporal ciliary body was 0.91±0.24m/s, and nasal ciliary body was 0.91±0.3m/s. The SWV of the lens values were out of range, this value was not detectable by this software. Elastography has proved to be a non-invasive procedure and feasible in dogs. The establishmentof the parameters of degree of rigidity of ocular structures will serve as a baseline for animals with eye disorders. Results may be extrapolated to primary research on the applicability of ARFI in the evaluation of ocular bulb in humans.(AU)

Estruturas oculares de cães braquicéfalos foram estudadas por elastografia acoustic radiation force impulse (ARFI) para estabelecer valores quantitativos e qualitativos de referência relacionados com a forma e a rigidez de algumas estruturas oculares. Foram avaliados 84 olhos de 42 cães braquicéfalos neste estudo. Os animais foram submetidos aos exames físico, laboratorial e aos exames oftalmológicos. Após a confirmação da sanidade dos pacientes, os cães foram submetidos à ultrassonografia e à elastografia ARFI, enfatizando-se o nervo óptico, o corpo ciliar e a lente. Para elastografia qualitativa, foram observadas características homogêneas no corpo ciliar e no nervo óptico. Os humores aquoso e vítreo foram visibilizados como imagens tipo mosaico. A elastografia quantitativa demonstrou velocidades de cisalhamento para nervo óptico de 1,01±0,27m/s, para corpo ciliar temporal de 0,91±0,24m/s e para corpo ciliar nasal de 0,91±0,3m/s. Valores dessas velocidades para lentes apresentaram-se fora do intervalo: X.XXm/s. A elastografia provou ser um procedimento não invasivo e viável para cães. Estabelecidos os parâmetros do grau de rigidez das estruturas oculares, futuramente tais dados servirão como padrão para avaliação de animais com os distúrbios oculares. Os resultados podem ser extrapolados para a pesquisa primária sobre a aplicabilidade da ARFI na avaliação do bulbo ocular em seres humanos.(AU)

Reproducibility of ultrasound-derived muscle thickness and echo-intensity for the entire quadriceps femoris muscle.

INTRODUCTION: Muscle thickness (MT) and muscle echo-intensity (EI) allow the study of skeletal muscle adaptive changes with ultrasound. This study investigates the intra- and inter-session reliability and agreement of MT and EI measurements for each of the four heads of the quadriceps femoris in transverse and longitudinal scans, using two sizes for the region of interest (ROI); EI measurements only. METHODS: Three B-mode images from two views were acquired from each head of quadriceps femoris from twenty participants (10 females) in two sessions, 7 days apart. EI was measured using a large and a small ROI. Reliability was examined with the mixed two-way intra-class correlation coefficient (ICC), the standard error of mean (SEM) and the smallest detectable change (SDC). Bland-Altman's plots were used to study agreement. RESULTS: High to very high inter-session ICC values were found for MT for all muscle heads, particularly for measurements from transverse scans. For EI measurement, ICC values ranged from low to high, with higher ICC values seen with the largest ROI. SDC values ranged between 0.19 and 0.53 cm for MT and between 3.73 and 18.56 arbitrary units (a.u.) for two ROIs. Good agreement existed between MT measurements made in both scans. A small bias and larger 95% limits of agreement were seen for EI measurements collected with the two ROI sizes. CONCLUSION: Ultrasound measures of MT and EI show moderate to very high reliability. The reliability and agreement of MT and EI measurements are improved in transverse scans and with larger ROIs.

Venous flow during manual lymphatic drainage applied to different regions of the lower extremity in people with and without chronic venous insufficiency: a cross-sectional study.

OBJECTIVES: To evaluate the effect of manual lymphatic drainage (MLD) on venous flow when applied to the medial and lateral aspects of the thigh and leg in patients with chronic venous insufficiency (CVI) and healthy subjects. DESIGN: Cross-sectional study. SETTING: Participants were assessed in a school-based health community attendant service. PARTICIPANTS: Fifty-seven subjects participated in this study {mean age: 43 [standard deviation (SD) 14] years, 38 women and 19 men}. Of these, 28 subjects had CVI [mean age 47 (SD 12) years] and 29 subjects did not have CVI [mean age 39 (14) years]. INTERVENTION: MLD was applied by a certificated physical therapist to the medial and lateral aspects of the thigh and leg. MAIN OUTCOME MEASUREMENTS: Cross-sectional area; blood flow velocities in the femoral vein, great saphenous vein, popliteal vein and small saphenous vein at baseline and during MLD, measured by duplex ultrasound. RESULTS: Flow volume in the femoral vein increased from baseline [5.19 (SD 3.25)cm3/second] when MLD was applied to the medial [7.03 (SD 3.65)cm3/second; P≤0.001; mean difference -1.69; 95% confidence interval (CI) -2.42 to -0.97] and lateral [6.16 (SD 3.35)cm3/second; P≤0.001; mean difference -1.04; 95% CI -1.70 to -0.39] aspects of the thigh. Venous flow augmentation in the femoral vein and great saphenous vein was higher when MLD was applied to the medial aspect of the thigh (P<0.001), while MLD had a similar effect on venous blood flow regardless of whether it was applied to the medial or the lateral aspect of the leg (P=0.731). CONCLUSIONS: MLD increases blood flow in deep and superficial veins. MLD should be applied along the route of the venous vessels for improved venous return.

Uso da técnica de swim-up para a remoção do Vírus da Artrite Encefalite Caprina do sêmen de reprodutores infectados / Use of swim-up technique for removal of the Caprine Arthritis Encephalitis Virus in the semen of infect bucks

Neste estudo, 67 ejaculados foram avaliados, antes e depois da técnica de swim-up, em relação à qualidade seminal e à presença do CAEV. Das 67 amostras testadas por PCRn, antes do swim-up, 47 (70,15%) foram positivas para o DNA pró-viral. No entanto, quatro amostras adicionais foram positivas ao RT-nested PCR após o swim-up, o que permite dizer que, pelo menos, 76,12% (51/67) delas estavam infectadas antes da lavagem. Todavia, em 23,88% (16/67) das amostras não foi detectada a presença do CAEV. Após a aplicação da técnica de swim-up, constatou-se, pela PCRn e RT-nested PCR, que houve uma redução significativa (χ²= 9,078; p<0,001) da presença do CAEV nas amostras seminais, pois 28 de 51 amostras positivas resultaram livres do vírus (54,90%), tanto para DNA pró-viral quanto para o vírus livre. Em relação à motilidade individual progressiva (MIP) e vigor espermático obtidos antes e depois da técnica de swim-up, observou-se uma diminuição significativa em suas médias, sendo o MIP de 86,42% para 71,49%, já o vigor espermático de 4,16 para 3,93. Conclui-se que a eliminação do CAEV no sêmen é de caráter intermitente, e que a associação da PCRn e RT-nested PCR é uma opção segura para a certificação sanitária individual das amostras seminais quanto à presença ou ausência do CAEV. Finalmente, a técnica de swim-up promove uma redução na infectividade de amostras de sêmen contaminadas, e, além disso, é possível promover a recuperação de espermatozoides viáveis.

In this study, 67 ejaculates were assessed before and after the swim-up technique in relation to semen quality and presence of CAEV. Of the 67 samples tested by Nested PCR, before swim-up 47 (70.15%) were positive for viral DNA. Furthermore, four additional samples were positive for RT-nested PCR after swim-up, which allows us to affirm that at least 76.12% (51/67) were infected before washing. However, 23.88% (16/67) of the samples did not detect the presence of CAEV. After application of the swim-up technique it was found, by Nested PCR and RT-nested PCR, that there was a significant decrease (χ² = 9.078, p <0.001) in the presence of CAEV in semen samples, once 28 of 51 positive samples were free from the virus (54.90%) for both proviral DNA and the free form of the virus. Regarding individual progressive motility (IPM) and spermatic vigor obtained before and after the swim-up technique, a significant decrease was observed in the average, being 86.42% of the IPM to 71.49% and the spermatic vigor from 4.16 for the 3.93. It is concluded that the removal of CAEV in semen has an intermittent character, and the combination of PCR and RT-nested PCR is a safe option for health certification of individual semen samples for the presence or absence of CAEV. Finally, the swim-up technique promotes a reduction in the infectivity of contaminated semen samples, and it is possible to promote the recovery of high individual progressive motility sperm and sperm vigor.

Antimicrobial activity of prodigiosin isolated from Serratia marcescens UFPEDA 398.

Prodigiosin is an alkaloid and natural red pigment produced by Serratia marcescens. Prodigiosin has antimicrobial, antimalarial and antitumor properties and induces apoptosis in T and B lymphocytes. These properties have piqued the interest of researchers in the fields of medicine, pharmaceutics and different industries. The aim of the present study was to evaluate the antimicrobial activity of prodigiosin against pathogenic micro-organisms. The red pigments produced by S. marcescens exhibited absorption at 534 nm, Rf of 0.59 and molecular weight of 323 m/z. Antimicrobial activity was tested against oxacillin-resistant Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis, Streptococcus pyogenes, Acinetobacter sp. and oxacillin-resistant S. aureus. The standard antibiotics employed were ampicillin, chloramphenicol, gentamicin and oxacillin. The disc-diffusion tests demonstrated significant inhibition zones for S. aureus (35 ± 0.6), E. faecalis (22 ± 1.0) and S. pyogenes (14 ± 0.6). However, prodigiosin showed resistance to E. coli, P. aeruginosa and acinetobacter, where no significant formation of inhibitory halos were observed. We determined the inhibitory minimum concentrations and bactericidal for 20 strains of oxacillin-resistant S. aureus (ORSA). The pattern was the antibiotic oxacillin. The minimum inhibitory concentrations observed ranged from 1, 2 and 4.0 µg/mL, respectively, while the minimum bactericidal concentrations ranged from 2, 4, 8 and 16 µg/mL. The S. marcescens prodigiosin produced by showed bactericidal and bacteriostatic effect showing promising antimicrobial activity and suggesting future studies regarding its applicability in antibiotics therapies directed ORSA.

Uso da técnica de swim-up para a remoção do Vírus da Artrite Encefalite Caprina do sêmen de reprodutores infectados / Use of swim-up technique for removal of the Caprine Arthritis Encephalitis Virus in the semen of infect bucks

Neste estudo, 67 ejaculados foram avaliados, antes e depois da técnica de swim-up, em relação à qualidade seminal e à presença do CAEV. Das 67 amostras testadas por PCRn, antes do swim-up, 47 (70,15%) foram positivas para o DNA pró-viral. No entanto, quatro amostras adicionais foram positivas ao RT-nested PCR após o swim-up, o que permite dizer que, pelo menos, 76,12% (51/67) delas estavam infectadas antes da lavagem. Todavia, em 23,88% (16/67) das amostras não foi detectada a presença do CAEV. Após a aplicação da técnica de swim-up, constatou-se, pela PCRn e RT-nested PCR, que houve uma redução significativa (²= 9,078, p<0,001) da presença do CAEV nas amostras seminais, pois 28 de 51 amostras positivas resultaram livres do vírus (54,90%), tanto para DNA pró-viral quanto para o vírus livre. Em relação à motilidade individual progressiva (MIP) e vigor espermático obtidos antes e depois da técnica de swim-up, observou-se uma diminuição significativa em suas médias, sendo o MIP de 86,42% para 71,49%, já o vigor espermático de 4,16 para 3,93. Conclui-se que a eliminação do CAEV no sêmen é de caráter intermitente, e que a associação da PCRn e RT-nested PCR é uma opção segura para a certificação sanitária individual das amostras seminais quanto à presença ou ausência do CAEV. Finalmente, a técnica de swim-up promove uma redução na infectividade de amostras de sêmen contaminadas, e, além disso, é possível promover a recuperação de espermatozoides viáveis.

In this study, 67 ejaculates were assessed before and after the swim-up technique in relation to semen quality and presence of CAEV. Of the 67 samples tested by Nested PCR, before swim-up 47 (70.15%) were positive for viral DNA. Furthermore, four additional samples were positive for RT-nested PCR after swim-up, which allows us to affirm that at least 76.12% (51/67) were infected before washing. However, 23.88% (16/67) of the samples did not detect the presence of CAEV. After application of the swim-up technique it was found, by Nested PCR and RT-nested PCR, that there was a significant decrease (² = 9.078, p <0.001) in the presence of CAEV in semen samples, once 28 of 51 positive samples were free from the virus (54.90%) for both proviral DNA and the free form of the virus. Regarding individual progressive motility (IPM) and spermatic vigor obtained before and after the swim-up technique, a significant decrease was observed in the average, being 86.42% of the IPM to 71.49% and the spermatic vigor from 4.16 for the 3.93. It is concluded that the removal of CAEV in semen has an intermittent character, and the combination of PCR and RT-nested PCR is a safe option for health certification of individual semen samples for the presence or absence of CAEV. Finally, the swim-up technique promotes a reduction in the infectivity of contaminated semen samples, and it is possible to promote the recovery of high individual progressive motility sperm and sperm vigor.

Effects of Human Mesenchymal Stem Cells Isolated from Wharton's Jelly of the Umbilical Cord and Conditioned Media on Skeletal Muscle Regeneration Using a Myectomy Model.

Skeletal muscle has good regenerative capacity, but the extent of muscle injury and the developed fibrosis might prevent complete regeneration. The in vivo application of human mesenchymal stem cells (HMSCs) of the umbilical cord and the conditioned media (CM) where the HMSCs were cultured and expanded, associated with different vehicles to induce muscle regeneration, was evaluated in a rat myectomy model. Two commercially available vehicles and a spherical hydrogel developed by our research group were used. The treated groups obtained interesting results in terms of muscle regeneration, both in the histological and in the functional assessments. A less evident scar tissue, demonstrated by collagen type I quantification, was present in the muscles treated with HMSCs or their CM. In terms of the histological evaluation performed by ISO 10993-6 scoring, it was observed that HMSCs apparently have a long-term negative effect, since the groups treated with CM presented better scores. CM could be considered an alternative to the in vivo transplantation of these cells, as it can benefit from the local tissue response to secreted molecules with similar results in terms of muscular regeneration. Searching for an optimal vehicle might be the key point in the future of skeletal muscle tissue engineering.

A new sheep model with automatized analysis of biomaterial-induced bone tissue regeneration.

Presently, several bone graft substitutes are being developed or already available for clinical use. However, the limited number of clinical and in vivo trials for direct comparison between these products may complicate this choice. One of the main reasons for this scarcity it is the use of models that do not readily allow the direct comparison of multiple bone graft substitutes, due especially to the small number of implantation sites. Although sheep cancellous bone models are now well established for these purposes, the limited availability of cancellous bone makes it difficult to find multiple comparable sites within a same animal. These limitations can be overcome by the monocortical model here proposed as it consists in 5-6 holes (5 mm Ø), in the femoral diaphysis, with similar bone structure, overlying soft tissue and loading pattern for all defects. Associated to this model, it is also described a fast histomorphometric analysis method using a computer image segmentation test (Threshold method) to assess bone regeneration parameters. The information compiled through the experimental use of 45 sheep in several studies allowed determining that this ovine model has the potential to demonstrate differences in bone-forming performance between various scaffolds. Additionally, the described histomorphometric method is fast, accurate and reproducible.

Identification of a novel subtype of feline immunodeficiency virus in a population of naturally infected felines in the Brazilian Federal District.

The feline immunodeficiency virus (FIV) is a retrovirus that is found worldwide, and it can be assigned to six subtypes (A, B, C, D, E, and a putative subtype F) based on sequencing analysis of the env and gag genes. Subtypes A and B are the most common worldwide. In Brazil, several authors have isolated only subtype B, and its prevalence differs markedly among investigated populations. Blood samples from 200 domestic felines from the Federal District in Brazil were analyzed by PCR. Samples that tested positive for FIV were then cloned, sequenced, and analyzed phylogenetically and statistically. The results represent the first description of FIV infection in the Central Region of Brazil and suggest that only 2 % of felines in this region are positive for the virus. In addition, the analysis showed that one out of the four positive samples that we detected could not be assigned to any of the six classical subtypes. This sample was taken as a putative novel subtype of the FIV virus. The remaining three positive samples were assigned to subtype B, with differences existing among these samples.

Regional variations in brain oxygenation during temporary clipping in aneurysm surgery.

OBJECTIVES: Brain tissue oxygen concentration (PbtO(2)) monitoring has been used in aneurysm surgery to detect decreased brain oxygenation during temporary clipping. The effects of circulatory interruption according to different aneurysm locations have not been established. In this work, variations in PbtO(2) during temporary clipping were studied in anterior communicating (AcomA), posterior communicating (PcomA) origin, and middle cerebral artery (MCA) aneurysm surgery. METHODS: PbtO(2) was monitored during surgery of 41 patients; aneurysms were located in the AcomA (10 cases), origin of PcomA (8 cases), and MCA bifurcation (23 cases). Temporary clips were used in all cases. Variations in PbtO(2) values obtained during application of temporary clips were evaluated and studied according to the duration and type of circulatory interruption for each aneurysm location. RESULTS: In AcomA aneurysm surgery, a significant decrease in PbtO(2) values was found in 31% of the periods of temporary clipping, whereas in PcomA and MCA aneurysm surgery, significant decreases were found in all temporary clip applications (100%). In MCA aneurysms, the amplitude of decrease in PbtO(2) was higher when the circulatory interruption lasted for 2 or more minutes, compared with shorter periods of temporary clipping. DISCUSSION: During temporary clipping, different variations in PbtO(2) values were obtained when comparing frontal and temporal regions of monitoring: in MCA and PcomA origin aneurysms, significant variations were registered in all periods of temporary regional circulatory interruption, but the same results were not found in frontal monitoring for AcomA aneurysm surgery.

Use of poly(DL-lactide-ε-caprolactone) membranes and mesenchymal stem cells from the Wharton's jelly of the umbilical cord for promoting nerve regeneration in axonotmesis: in vitro and in vivo analysis.

Cellular systems implanted into an injured nerve may produce growth factors or extracellular matrix molecules, modulate the inflammatory process and eventually improve nerve regeneration. In the present study, we evaluated the therapeutic value of human umbilical cord matrix MSCs (HMSCs) on rat sciatic nerve after axonotmesis injury associated to Vivosorb® membrane. During HMSCs expansion and differentiation in neuroglial-like cells, the culture medium was collected at 48, 72 and 96 h for nuclear magnetic resonance (NMR) analysis in order to evaluate the metabolic profile. To correlate the HMSCs ability to differentiate and survival capacity in the presence of the Vivosorb® membrane, the [Ca(2+)]i of undifferentiated HMSCs or neuroglial-differentiated HMSCs was determined by the epifluorescence technique using the Fura-2AM probe. The Vivosorb® membrane proved to be adequate and used as scaffold associated with undifferentiated HMSCs or neuroglial-differentiated HMSCs. In vivo testing was carried out in adult rats where a sciatic nerve axonotmesis injury was treated with undifferentiated HMSCs or neuroglial differentiated HMSCs with or without the Vivosorb® membrane. Motor and sensory functional recovery was evaluated throughout a healing period of 12 weeks using sciatic functional index (SFI), extensor postural thrust (EPT), and withdrawal reflex latency (WRL). Stereological analysis was carried out on regenerated nerve fibers. In vitro investigation showed the formation of typical neuroglial cells after differentiation, which were positively stained for the typical specific neuroglial markers such as the GFAP, the GAP-43 and NeuN. NMR showed clear evidence that HMSCs expansion is glycolysis-dependent but their differentiation requires the switch of the metabolic profile to oxidative metabolism. In vivo studies showed enhanced recovery of motor and sensory function in animals treated with transplanted undifferentiated and differentiated HMSCs that was accompanied by an increase in myelin sheath. Taken together, HMSC from the umbilical cord Wharton jelly might be useful for improving the clinical outcome after peripheral nerve lesion.

Optimization of artificial neural network models through genetic algorithms for surface ozone concentration forecasting.

INTRODUCTION: This study proposes three methodologies to define artificial neural network models through genetic algorithms (GAs) to predict the next-day hourly average surface ozone (O(3)) concentrations. GAs were applied to define the activation function in hidden layer and the number of hidden neurons. METHODS: Two of the methodologies define threshold models, which assume that the behaviour of the dependent variable (O(3) concentrations) changes when it enters in a different regime (two and four regimes were considered in this study). The change from one regime to another depends on a specific value (threshold value) of an explanatory variable (threshold variable), which is also defined by GAs. The predictor variables were the hourly average concentrations of carbon monoxide (CO), nitrogen oxide, nitrogen dioxide (NO(2)), and O(3) (recorded in the previous day at an urban site with traffic influence) and also meteorological data (hourly averages of temperature, solar radiation, relative humidity and wind speed). The study was performed for the period from May to August 2004. RESULTS AND DISCUSSION: Several models were achieved and only the best model of each methodology was analysed. In threshold models, the variables selected by GAs to define the O(3) regimes were temperature, CO and NO(2) concentrations, due to their importance in O(3) chemistry in an urban atmosphere. CONCLUSION: In the prediction of O(3) concentrations, the threshold model that considers two regimes was the one that fitted the data most efficiently.

Intraoperative brain oxygenation monitoring and vasospasm in aneurysmal subarachnoid hemorrhage.

BACKGROUND: Vasospasm is a frequent complication of subarachnoid hemorrhage (SAH), implicated in poor outcome, and prediction of its occurrence might be important on the therapeutic approach of this condition. Brain oxygenation in aneurysmal SAH was prospectively monitored during surgery in 28 patients, using brain tissue oxygen pressure (PbtO(2)), studying its association with the occurrence of post-operative vasospasm, detected by transcranial Doppler. METHODS: PbtO(2) monitoring was performed during surgery of 28 patients with aneurysmal SAH, using a polarographic microcatheter (Licox; GMS, Kiel, Germany), inserted into the cerebral tissue. The aneurysms were localized in the anterior communicating artery (AcoA) complex (eight cases), in the posterior communicating artery (Pcom) origin (seven cases), and in the middle cerebral artery (MCA) bifurcation (13 cases). Basal PbtO(2) values, obtained immediately before application of temporary or definitive clips, were studied according to age, clinical status and CT findings. The association between the basal values and the occurrence of increased blood flow velocity in the post-operative transcranial Doppler (TCD vasospasm) was investigated. RESULTS: Post-operative TCD vasospasm developed in 13 patients, all of them with basal values inferior to 10 mmHg. PbtO(2) basal value was significantly lower in cases that developed TCD vasospasm. This association was independent of age, clinical status, or CT findings. CONCLUSION: The finding of low intraoperative basal PbtO(2) values may be an indicator for a high risk of occurrence of post-operative TCD vasospasm in cases of aneurysmatic SAH.