Effect of untreated and pretreated sugarcane molasses on growth performance of Haematococcus pluvialis microalgae in inorganic fertilizer and macrophyte extract culture media.

The growth of Haematococcus pluvialis in two alternative culture media NPK (10:10:10) and ME (macrophyte extract), under mixotrophic conditions using sugarcane molasses as a carbon source were evaluated for 28 days. The molasses was used in two different ways, in a native form (untreated) and a hydrolyzed (pretreated). Cell density of Haematococcus pluvialis in mixotrophic cultivation was higher in pretreated molasses. Growth rate was higher when pretreated molasses were employed in mixotrophic cultivation with NPK culture medium (k=0.5 7th growth day). Biomass, chlorophyll-a, conductivity and total inorganic nitrogen were not significantly different (p>0.05) during the experimental period for two mixotrophic cultivation and culture media. Protein contents of H. pluvialis biomass were higher in NPK culture medium with pretreated molasses (50% dry biomass). Annual biomass production was 520 kg-1 dry biomass with untreated molasses for two culture media, and 650 and 520 kg-1 dry biomass with pretreated molasses for NPK and ME culture media, respectively. The use of NPK and ME culture media in mixotrophic cultivation may be a new protocol for H. pluvialis cultivation due to the low cost and similar annual production.

Pregnancy in a woman with recurrent immunoglobulin a nephropathy: A case report.

Immunoglobulin A nephropathy (IgAN) is the most common form of primary glomerulonephritis and is increasingly encountered in pregnancy. The obstetric and renal outcomes of pregnancy are controversial, however. Women with IgAN are at higher risk of hypertension, preeclampsia and foetal loss; the prognosis is worse for those who have advanced chronic kidney disease and proteinuria. Here we report the case of a 32-year-old nulliparous woman with chronic hypertension who conceived during an active phase of her IgAN, which had been diagnosed 8 years earlier. Antihypertensive therapies and a low-protein diet were key to her reaching 34 weeks' gestation with acceptable kidney function. Rupture of membranes occurred at 34 weeks 3 days' gestation and a healthy boy was delivered the next day. This report aims to provide clinicians with useful information for the management of patients with IgAN during pregnancy.

Thermal and photo-stability of the antioxidant potential of Spirulina platensis powder / Estabilidade térmica e fotoestabilidade do potencial antioxidante de Spirulina platensis em pó

Abstract This work aimed to evaluate the thermal and photo stability of the antioxidant potential (AP) of the Spirulina platensis biomass. Thermal stability was established at 25ºC, 40ºC and 50ºC for 60 days, in the dark, protected from light. Photo stability was evaluated using UV (15 W, λ = 265 nm) and fluorescent (20 W, 0.16 A, power factor FP > 0.5, 50/60 Hz, 60 lm/w, 1200 lm) light for 90 days in capsules, glass and Petri dishes, at room temperature. The AP of the biomass in these conditions was determined at intervals (every 7 and 30 days in the studies of thermal and photo stability, respectively) using the induction of the oxidation of a lipid system by heat and aeration. In this lipid system, the biomass submitted to degradation was used as an antioxidant. The kinetics of the reaction was determined by the Arrhenius method. Thermal degradation was found to follow zero order kinetics, whereas photo degradation followed first order kinetics. The AP decreased 50% after 50 days at 25°C. At 40°C and 50°C, the AP decreased more than 50% after 35 and 21 days of exposition, respectively. The decrease of the AP of Spirulina was more sensible to UV and fluorescence light. After 30 days of exposition, the AP decreased more than 50% in all storage conditions tested. The antioxidant potential of Spirulina platensis is easily degraded when the biomass is exposed to heat and light, indicating the need for care to be taken in its storage.

Resumo Este trabalho objetivou avaliar a estabilidade térmica e a foto-estabilidade do potencial antioxidante (PA) da biomassa da Spirulina platensis. A estabilidade térmica foi avaliada a 25ºC, 40ºC e 50ºC por 60 dias. A foto-estabilidade foi avaliada usando luz UV (15 W, λ = 265 nm) e fluorescente (20 W, 0.16 A, fator de potência FP > 0.5, 50/60 Hz, 60 lm/w, 1200 lm) por 90 dias em cápsulas, vidro e placas de Petri. O PA da biomassa nessas condições foi determinado em intervalos de tempo (a cada 7 e 30 dias nos estudos de estabilidade térmica e foto-estabilidade, respectivamente), usando a indução da oxidação de um sistema lipídico por calor e aeração. Neste sistema lipídico, a biomassa submetida à degradação foi usada como antioxidante. A cinética da reação foi determinada pelo método de Arrhenius. A degradação térmica seguiu uma cinética de zero ordem, enquanto que a fotodegradação seguiu uma cinética de primeira ordem. O PA diminuiu 50% depois de 50 dias a 25°C. A 40°C e 50°C, o PA diminuiu mais de 50% depois de 35 e 21 dias de exposição, respectivamente. A diminuição do PA da Spirulina foi mais sensível à luz UV e fluorescente. Depois de 30 dias de exposição, o PA diminuiu mais de 50% em todas as condições de armazenamento testadas. O potencial antioxidante da Spirulina platensis é facilmente diminuído quando a biomassa é exposta ao calor e a luz, indicando a necessidade de cuidados durante seu armazenamento.

Heat Transfer Capability of (Ethylene Glycol + Water)-Based Nanofluids Containing Graphene Nanoplatelets: Design and Thermophysical Profile.

This research aims at studying the stability and thermophysical properties of nanofluids designed as dispersions of sulfonic acid-functionalized graphene nanoplatelets in an (ethylene glycol + water) mixture at (10:90)% mass ratio. Nanofluid preparation conditions were defined through a stability analysis based on zeta potential and dynamic light scattering (DLS) measurements. Thermal conductivity, dynamic viscosity, and density were experimentally measured in the temperature range from 283.15 to 343.15 K and nanoparticle mass concentrations of up to 0.50% by using a transient plate source, a rotational rheometer, and a vibrating-tube technique, respectively. Thermal conductivity enhancements reach up to 5% without a clear effect of temperature while rheological tests evidence a Newtonian behavior of the studied nanofluids. Different equations such as the Nan, Vogel-Fulcher-Tamman (VFT), or Maron-Pierce (MP) models were utilized to describe the temperature or nanoparticle concentration dependences of thermal conductivity and viscosity. Finally, different figures of merit based on the experimental values of thermophysical properties were also used to compare the heat transfer capability and pumping power between nanofluids and base fluid.

Thermal and photo-stability of the antioxidant potential of Spirulina platensis powder.

This work aimed to evaluate the thermal and photo stability of the antioxidant potential (AP) of the Spirulina platensis biomass. Thermal stability was established at 25ºC, 40ºC and 50ºC for 60 days, in the dark, protected from light. Photo stability was evaluated using UV (15 W, λ = 265 nm) and fluorescent (20 W, 0.16 A, power factor FP > 0.5, 50/60 Hz, 60 lm/w, 1200 lm) light for 90 days in capsules, glass and Petri dishes, at room temperature. The AP of the biomass in these conditions was determined at intervals (every 7 and 30 days in the studies of thermal and photo stability, respectively) using the induction of the oxidation of a lipid system by heat and aeration. In this lipid system, the biomass submitted to degradation was used as an antioxidant. The kinetics of the reaction was determined by the Arrhenius method. Thermal degradation was found to follow zero order kinetics, whereas photo degradation followed first order kinetics. The AP decreased 50% after 50 days at 25°C. At 40°C and 50°C, the AP decreased more than 50% after 35 and 21 days of exposition, respectively. The decrease of the AP of Spirulina was more sensible to UV and fluorescence light. After 30 days of exposition, the AP decreased more than 50% in all storage conditions tested. The antioxidant potential of Spirulina platensis is easily degraded when the biomass is exposed to heat and light, indicating the need for care to be taken in its storage.

Optical Properties of Mixed Nanofluids Containing Carbon Nanohorns and Silver Nanoparticles for Solar Energy Applications.

Different kinds of nanofluids show peculiar characteristics. In this work, a mixed nanofluid consisting of single-wall carbon nanohorns and silver nanoparticles aqueous suspensions is prepared and optically characterized, in the perspective to merge the favorable optical characteristics of carbon nanohorn-based nanofluids to the good thermal properties of silver-nanofluids. For the samples, both the spectral extinction and the scattering albedo at discrete wavelengths have been investigated. The silver nanoparticle plasmonic peak in the visible range further improves the overall nanofluid sunlight absorption properties, opening interesting perspectives for using such mixed nanofluids as solar absorber and heat transfer media in solar thermal collectors.

Influence of Cu, TiO2 Nanoparticles and Carbon Nano-Horns on Tribological Properties of Engine Oil.

The addition of nanoparticles in lubricating oils recently demonstrated to reduce the coefficient of friction and to increase the load-carrying capability of lubricant in coupled surfaces. In this work, different kinds of nanoparticles were tested as additives to engine oil to improve lubrication: copper and titanium oxide nanoparticles and single walled carbon nanohorns (SWCNHs). Two nanoparticle sizes were also tested in case of copper. The tribological properties of these nanofluids were evaluated by Stribeck tests, in order to compare the effect of nanoparticles on friction coefficient and electric contact resistance in different lubrication regimes. Stribeck curves showed that the coefficient of friction was reduced, compared to raw oil, by the action of Cu nanoparticles having 130 nm diameter, leading to a mean decrease of about 17%, and by SWCNHs, with a mean decrease of about 12%. Conversely, no significant changes were detected in presence of Cu nanoparticles having 50 nm diameter or of TiO2. The suspension viscosity and stability were also tested. Wear tests were also carried out, showing a reduction of wear rate up to nearly 50% for Cu nanoparticles (150 nm diameter) and around 30% for SWCNHs. The measurements showed that nanoparticles having size comparable to the mean roughness of coupled surfaces significantly improved the tribological properties of bare oil. An explanation of nanoparticle action is proposed.

A preliminary investigation on nanohorn toxicity in marine mussels and polychaetes.

Single walled carbon nanohorns (SWCNHs) are a black nanoscale spherical aggregate of cylindrical tubes of graphitic carbon which differ from nanotubes in their "horn-like" shape. Their peculiar structure makes them one of the best electronconductors at a nanoscale level. Although not commercially exploited, their rapid environmental diffusion is expected to rise significantly in the next few years. Therefore, we appraised the ecotoxicology of SWCNH powders by taking into account the ecological role of the two species that were deployed in exposure experiments: polychaetes, Hediste diversicolor, and mussels, Mytilus galloprovincialis. Adult mussels and polychaetes were exposed to three SWCNH concentrations: 1, 5, and 10 mg L(-1) and acute effects were measured after 24 and 48 h. Sub-lethal effects were estimated at level of physiological functions such as digestion in mussels (i.e. variations in lysosomal parameters and lipofuscin content) and the antioxidant system in both species (i.e. glutathione peroxidase activity and malondialdehyde content). SWCNH suspension in sea water was also characterised, highlighting the formation of aggregates the size of which was related to SWCNH concentrations and their resident time in the medium. The results showed that SWCNH affected the oxidative and lysosomal systems on the hepatopancreas and led to lysosomal alterations on haemocytes in mussels. The biological responses were less clear in polychaetes. This preliminary investigation highlighted the need of focusing future research efforts on possible physiological impairments caused by long-term exposure to SWCNHs in marine species.

Dynamic magnetic resonance imaging in acute pyelonephritis.

PURPOSE: This study was conducted to evaluate the role and clinical impact of dynamic magnetic resonance imaging (MRI) in the diagnosis and follow-up of acute pyelonephritis (APN). MATERIALS AND METHODS: We retrospectively reviewed 442 consecutive renal MRI examinations (279 diagnostic and 163 follow-up) performed in 285 patients (mean age 42.17 years), 35 of whom were kidney transplant recipients with a clinical suspicion of APN. RESULTS: MRI showed signal abnormalities suggestive of APN in 125/244 (51.2%) patients with native kidneys. Except for two examinations performed without paramagnetic contrast material, the inflammatory foci appeared as areas of nonenhancement: single in 39/123 cases, multiple in 84/123, unilateral in 60/84 and bilateral in 24/84. Abscesses were present in 40/123 (32.5%) positive cases. During follow-up, we observed complete normalisation of MRI signs in 86/103 patients; 17/103 (16.5%) cases evolved into fibrosis and scarring. In 15/35 (42.8%) patients with transplanted kidney, MRI was positive for APN. CONCLUSIONS: Renal MRI is an effective tool for the diagnosis and follow-up of APN both in patients not at risk and those at higher risk, such as those with a transplanted kidney. The high costs of the examination are offset by better treatment planning and early complication detection.

Avaliação da atividade antibacteriana da microalga Spirulina platensis / Assessment of the antibacterial activity of microalgae Spirulina platensis

Infecções são agravadas pelo aumento da resistência dos microrganismos a substâncias antimicrobianas. A necessidade de descoberta de novos medicamentos em decorrência desta resistência microbiana tem impulsionado o desenvolvimento de novas pesquisas. A Spirulina platensis, reconhecida pelas suas propriedades nutricionais, possui alta quantidade de compostos fenólicos, os quais podem apresentar também propriedades antimicrobianas. Objetivou-se cultivar a microalga Spirulina platensis, avaliar a produção de compostos fenólicos pela mesma, caracterizar a possível atividade antimicrobiana dos fenóis frente a Escherichia coli ATCC 25922, a Pseudomas aeruginosa ATCC 27853 e o Staphylococcus aureus ATCC 6538P e determinar a concentração inibitória mínima do extrato fenólico frente às bactérias citadas. Os resultados demonstraram que elevadas concentrações de nitrato de sódio (4g/L) no meio de cultivo não aumentaram a produção de compostos fenólicos. A microalga cultivada com 2 g/L de nitrato de sódio apresentou 2,13 mg/g de compostos fenólicos, sendo que os extratos apresentaram atividade antibacteriana contra o S. aureus, bactéria Grampositiva, com halo de inibição de 22 mm e 19 mm e concentração inibitória mínima de 47,46 mg/mL, indicando sua importância como potencial inibidor de S. aureus.

Bacterial infections are aggravated by the increasing resistance of microorganisms to antimicrobial substances. The need to discover new medicines to evade microbial resistance is the driving force behind much new research. The microalga Spirulina platensis, recognized for its nutritional properties, has a high content of phenolic compounds, which can provide antimicrobial properties. The objective of this study was to establish a culture of Spirulina platensis, estimate the production of phenolic compounds by this microalga, characterize the antimicrobial activity of the phenolics against microorganisms such as Escherichia coli ATCC 25922, Pseudomas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 6538P and determine the minimum inhibitory concentration (MIC) of the phenolic extract for these bacteria. It was found that adding high concentrations of sodium nitrate (4 g/L) to the medium did not increase the production of phenolic compounds. The microalgae grown with 2 g/L sodium nitrate produced 2.13 mg/g of phenolic compounds, and the extracts showed antibacterial activity against S. aureus, a Gram-positive bacterium, with inhibition haloes of 22 mm and 19 mm and a MIC of 47.46 mg/ mL, indicating its importance as a potential S. aureus inhibitor.

Posterior psoas vs 3-in-1 approach for lateral femoral cutaneous and obturator nerve block for anterior cruciate ligament repair.

AIM: The aim of this article was to test the hypothesis that the posterior psoas compartment approach to the lumbar plexus help to achieve better blockade of the lateral femoral cutaneous and obturator nerves than the classic anterior 3-in-1 femoral nerve block. METHODS: Thirty-six patients who were undergoing anterior cruciate ligament repair were randomly allocated to receive a femoral nerve block using either an anterior 3-in-1 femoral block (group Femoral, N=18) or a posterior psoas compartment approach (group Psoas, N=18) using 30 mL of 1.5% mepivacaine. Successful nerve block was defined as a complete loss of pinprick sensation in the region that is supplied by the lateral femoral cutaneous nerve along with adequate motor block of the obturator nerve 30 minutes after injection. The degree of motor block of the obturator nerve was measured using adduction strength with a mercury sphygmomanometer as previously described by Lang. RESULTS: Thirty minutes after the completion of the block, sensory block of the lateral femoral cutaneous nerve was observed in 14 patients (78%) from the Psoas group and in 3 patients (17%) from the Femoral group (P=0.001). Thirty minutes after the completion of the block, a 119+/-40 mmHg decrease was found in Psoas group, in contrast to the 25+/-22 mmHg decrease found in the Femoral group (P<0.0005). CONCLUSIONS: The posterior psoas compartment approach provides a more reliable block of the lateral femoral cutaneous and obturator nerves than the anterior 3-in-1 approach.

Prospective clinical evaluation of 1920 Morse taper connection implants: results after 4 years of functional loading.

PURPOSE: This study evaluated the survival rate and the clinical, radiographic and prosthetic success of 1920 Morse taper connection implants. MATERIAL AND METHODS: One thousand nine hundred and twenty Morse taper connection implants were inserted in 689 consecutive patients, from January 2003 until December 2006. Implants were clinically and radiographically evaluated at 12, 24, 36 and 48 months after insertion (mean follow-up per implant: 25.42 months). Modified plaque index (mPI), modified sulcus bleeding index, probing depth (PD) and the distance between implant shoulder and first crestal bone-implant contact (DIB) were measured in mm. Success criteria included the absence of suppuration and clinically detectable implant mobility, PD<5 mm, DIB<1.5 mm after 12 months of functional loading and not exceeding 0.2 mm for each following year, the absence of recurrent prosthetic complications at the implant-abutment interface. Prosthetic restorations were fixed partial prostheses (364 units), single crowns (SCs: 307 units), fixed full-arch prostheses (53 units) and overdentures (67 units). RESULTS: The overall cumulative implant survival rate was 97.56% (96.12% in the maxilla and 98.91% in the mandible). The cumulative implant success rate was 96.61% (95.25% in the maxilla and 98.64% in the mandible). Only a few prosthetic complications were reported (0.65% of loosening at implant-abutment interface in SCs). CONCLUSION: The use of Morse taper connection implants represents a successful procedure for the rehabilitation of partially and completely edentulous arches. The absence of an implant-abutment interface (microgap) is associated with minimal crestal bone loss. The high mechanical stability significantly reduces prosthetic complications.