Bioremediation of a polymetallic, arsenic-dominated reverse osmosis reject stream.

The treatment of metal-laden industrial effluents by reverse osmosis is gaining in popularity worldwide due to its high performance. However, this process generates a polymetallic concentrate (retentate) stream in need of efficient post-treatment prior to environmental discharge. This paper presents results on the bioremediation (in batch mode) of a metal-laden, arsenic-dominated retentate using Shewanella sp. O23S as inoculum. The incubation of the retentate for 14 days under anoxic conditions resulted in the following removal yields: As (8%), Co (11%), Mo (3%), Se (62%), Sb (30%) and Zn (40%). The addition of 1 mmol l-1 cysteine increased the removal rate as follows: As (27%), Co (80%), Mo (78%), Se (88%), Sb (83%) and Zn (90%). The contribution of cysteine as a source of H2 S to enhancing the removal yield was confirmed by its addition after 7 days of incubations initially lacking it. Additionally, the cysteine-sourced H2 S was confirmed by its capture onto headspace-mounted Pb-acetate test strips that were analysed by X-ray diffraction. We show that real metal-laden industrial effluents can be treated to medium-to-high efficiency using a biological system (naturally sourced inocula) and inexpensive reagents (yeast extract, lactate and cysteine).

The Use of Silica Microparticles to Improve the Efficiency of Optical Hyperthermia (OH).

Although optical hyperthermia could be a promising anticancer therapy, the need for high concentrations of light-absorbing metal nanoparticles and high-intensity lasers, or large exposure times, could discourage its use due to the toxicity that they could imply. In this article, we explore a possible role of silica microparticles that have high biocompatibility and that scatter light, when used in combination with conventional nanoparticles, to reduce those high concentrations of particles and/or those intense laser beams, in order to improve the biocompatibility of the overall procedure. Our underlying hypothesis is that the scattering of light caused by the microparticles would increase the optical density of the irradiated volume due to the production of multiple reflections of the incident light: the nanoparticles present in the same volume would absorb more energy from the laser than without the presence of silica particles, resulting either in higher heat production or in the need for less laser power or absorbing particles for the same required temperature rise. Testing this new optical hyperthermia procedure, based on the use of a mixture of silica and metallic particles, we have measured cell mortality in vitro experiments with murine glioma (CT-2A) and mouse osteoblastic (MC3T3-E1) cell lines. We have used gold nanorods (GNRs) that absorb light with a wavelength of 808 nm, which are conventional in optical hyperthermia, and silica microparticles spheres (hereinafter referred to as SMSs) with a diameter size to scatter the light of this wavelength. The obtained results confirm our initial hypothesis, because a high mortality rate is achieved with reduced concentrations of GNR. We found a difference in mortality between CT2A cancer cells and cells considered non-cancer MC3T3, maintaining the same conditions, which gives indications that this technique possibly improves the efficiency in the cell survival. This might be related with differences in the proliferation rate. Since the experiments were carried out in the 2D dimensions of the Petri dishes, due to sedimentation of the silica particles at the bottom, whilst light scattering is a 3D phenomenon, a large amount of the energy provided by the laser escapes outside the medium. Therefore, better results might be expected when applying this methodology in tissues, which are 3D structures, where the multiple reflections of light we believe will produce higher optical density in comparison to the conventional case of no using scattering particles. Accordingly, further studies deserve to be carried out in this line of work in order to improve the optical hyperthermia technique.

Phase I clinical trial of nintedanib plus paclitaxel in early HER-2-negative breast cancer (CNIO-BR-01-2010/GEICAM-2010-10 study).

INTRODUCTION: Previous small-molecule antiangiogenics have compromised chemotherapy dose intensity in breast cancer. We present a phase I trial of a novel selective agent, nintedanib, plus standard chemotherapy in early breast cancer. METHODS: Her-2-negative breast cancer patients with tumours larger than 2 cm were eligible for dose-escalation trial (classic 3+3 method). RESULTS: The recommended phase II dose (RP2D) was 150 mg BID of nintedanib combined with standard dose of weekly paclitaxel followed by adriamycin plus cyclophosphamide. The dose-limiting toxicity was transaminase elevation. At the RP2D, the dose intensity was ∼100%. The pathologic complete response was 50%. CONCLUSIONS: The combination allows the delivery of full-dose intensity, while efficacy seems promising.

Direct nanoscale observations of CO2 sequestration during brucite [Mg(OH)2] dissolution.

The dissolution and carbonation of brucite on (001) cleavage surfaces was investigated in a series of in situ and ex situ atomic force microscopy (AFM) experiments at varying pH (2-12), temperature (23-40 °C), aqueous NaHCO(3) concentration (10(-5)-1 M), and PCO(2) (0-1 atm). Dissolution rates increased with decreasing pH and increasing NaHCO(3) concentration. Simultaneously with dissolution of brucite, the growth of a Mg-carbonate phase (probably dypingite) was directly observed. In NaHCO(3) solutions (pH 7.2-9.3,), precipitation of Mg-carbonates was limited. Enhanced precipitation was, however, observed in acidified NaHCO(3) solutions (pH 5, DIC ≈ 25.5 mM) and in solutions that were equilibrated under a CO(2) atmosphere (pH 4, DIC ≈ 25.2 mM). Nucleation predominantly occurred in areas of high dissolution such as deep step edges suggesting that the carbonation reaction is locally diffusion-transport controlled. More extensive particle growth was also observed after ex situ experiments lasting for several hours. This AFM study contributes to an improved understanding of the mechanism of aqueous brucite carbonation at low temperature and pressure conditions and has implications for carbonation reactions in general.

Microstructure and rheology of lime putty.

The rheology of lime binders, which is critical in the final performance of lime mortars and plasters, is poorly understood, particularly in its relationship with the microstructure and colloidal characteristics of slaked lime (Ca(OH)(2)) suspensions (i.e., lime putties). Here, the contrasting flow behavior of lime putties obtained upon slaking (hydration) of soft and hard burnt quicklimes (CaO) is compared and discussed in terms of the differences found in particle size, morphology, degree of aggregation, and fractal nature of aggregates as well as their evolution with aging time. We show that lime putties behave as non-Newtonian fluids, with thixotropic and rheopectic behavior observed for hard and soft burnt limes, respectively. Aggregation of portlandite nanoparticles in the aqueous suspension controls the time evolution of the rheological properties of lime putty, which is also influenced by the dominant slaking mechanism, that is, liquid versus vapor slaking in hard and soft burnt quicklimes, respectively. These results may be of relevance in the selection of optimal procedures and conditions for the preparation of lime mortars used in the conservation of historical buildings.

Pancreatic glucagonoma presenting as a pulmonary mass.

Glucagonoma is an uncommon disease, a neuroendocrine tumour that develops from glucagon-producing pancreatic cells. They are usually slow-growing, but generally advanced at diagnosis, and metastatic disease is virtually incurable. Liver is the most common site of metastatic disease. We present the case of a 48-year-old man with a glucagonoma being diagnosed from a pulmonary mass. This case had no liver affection in the whole evolution of the disease, and showed a particularly aggressive course, with very little response to all therapies administered, and a survival from diagnosis of just 16 months.

Pancreatic glucagonoma presenting as a pulmonary mass

Glucagonoma is an uncommon disease, a neuroendocrine tumour that develops from glucagon-producing pancreatic cells. They are usually slow-growing, but generally advanced at diagnosis, and metastatic disease is virtually incurable. Liver is the most common site of metastatic disease. We present the case of a 48-year-old man with a glucagonoma being diagnosed from a pulmonary mass. This case had no liver affection in the whole evolution of the disease, and showed a particularly aggressive course, with very little response to all therapies administered, and a survival from diagnosis of just 16 months (AU)

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EGFR and colon cancer: a clinical view.

Signalling pathways that emerge from EGFR activation are critical in colon cancer (CC) biology. Its targeting with specific drugs has opened a new window in the treatment of this disease. In this regard, monoclonal antibodies (mAb) have evidenced a high degree of efficiency opposed to the uselessness of tyrosine-kinase inhibitors. Cetuximab is the mAb that has evidenced most activity in CC. After its initial approval as an irinotecan-resistance reversal agent, cetuximab has demonstrated its efficiency from the first line to heavily pretreated patients. In the first line, its addition may increase response rate to chemotherapy, improving liver metastases resection rate. Another promising approach has been suggested from combination schedules with bevacizumab. Panitumumab has been recently approved for CC. Although there is limited clinical experience, the latest data have confirmed its activity in heavily pretreated patients resulting in a clinical benefit vs. best support care. In spite of the clinical benefits, adverse events and the high sanitary cost derived from these drugs force the selection of patients with the highest probability of benefit. At the moment, when EGFR expression evidenced by immunohistochemistry has no value, skin toxicity and, fundamentally, K-Ras mutations may hint at critical information for confirmatory prospective studies.

EGFR and colon cancer: a clinical view

Signalling pathways that emerge from EGFR activation are critical in colon cancer (CC) biology. Its targeting with specific drugs has opened a new window in the treatment of this disease. In this regard, monoclonal antibodies (mAb) have evidenced a high degree of efficiency opposed to the uselessness of tyrosine-kinase inhibitors. Cetuximab is the mAb that has evidenced most activity in CC. After its initial approval as an irinotecan-resistance reversal agent, cetuximab has demonstrated its efficiency from the first line to heavily pretreated patients. In the first line, its addition may increase response rate to chemotherapy, improving liver metastases resection rate. Another promising approach has been suggested from combination schedules with bevacizumab. Panitumumab has been recently approved for CC. Although there is limited clinical experience, the latest data have confirmed its activity in heavily pretreated patients resulting in a clinical benefit vs. best support care. In spite of the clinical benefits, adverse events and the high sanitary cost derived from these drugs force the selection of patients with the highest probability of benefit. At the moment, when EGFR expression evidenced by immunohistochemistry has no value, skin toxicity and, fundamentally, K-Ras mutations may hint at critical information for confirmatory prospective studies (AU)

Nanostructure and irreversible colloidal behavior of Ca(OH)2: implications in cultural heritage conservation.

Although Ca(OH)2 is one of the oldest art and building material used by mankind, little is known about its nanostructural and colloidal characteristics that play a crucial role in its ultimate performance as a binder in lime mortars and plasters. In particular, it is unknown why hydrated lime putty behaves as an irreversible colloid once dried. Such effect dramatically affects the reactivity and rheology of hydrated lime dispersions. Here we show that the irreversible colloidal behavior of Ca(OH)2 dispersions is the result of an oriented aggregation mechanism triggered by drying. Kinetic stability and particle size distribution analysis of oven-dried slaked lime or commercial dry hydrate dispersions exhibit a significant increase in settling speed and particle (cluster) size in comparison to slaked lime putty that has never been dried. Drying-related particle aggregation also leads to a significant reduction in surface area. Electron microscopy analyses show porous, randomly oriented, micron-sized clusters that are dominant in the dispersions both before and after drying. However, oriented aggregation of the primary Ca(OH)2 nanocrystals (approximately 60 nm in size) is also observed. Oriented aggregation occurs both before and during drying, and although limited before drying, it is extensive during drying. Nanocrystals self-assemble in a crystallographically oriented manner either along the 100 or equivalent 110 directions, or along the Ca(OH)2 basal planes, i.e., along [001]. While random aggregation appears to be reversible, oriented aggregation is not. The strong coherent bonding among oriented nanoparticles prevents disaggregation upon redispersion in water. The observed irreversible colloidal behavior associated with drying of Ca(OH)2 dispersions has important implications in heritage conservation, particularly considering that nowadays hydrated lime is often the preferred alternative to portland cement in architectural heritage conservation. Finally, our study demonstrates that, fortuitously, hydrated lime could be one of the first nanomaterials used by mankind.

Development of a technique for using 99mTc as an adsorbable tracer for hydrodynamic studies of fine sediments in suspension.

Labelling of fine sediment (phi < 62.5 microm) with 99mTc was achieved through laboratory experiments described in a previous work (Proceedings of an International Symposium on Isotope Techniques in Water Resources Development and Management. IAEA-SM-361/13, Vienna, Proceedings of the XIIIth Brazilian Symposium on Water Resources. Brazilian Association for Water Resources (ABRH), Belo Horizonte, paper 176, CD-rom (in Portuguese)). Comparative studies of the hydrodynamic behaviour of the labelled and unlabelled sediment, in order to validate the application of the labelled sediment in field studies, were further performed by means of sedimentation tests using the Andreasen pipette technique, and are presented here. Labelling without flocculation, which promotes the same sedimentation behaviour of the labelled and the natural sediment was only achieved using small quantities of SnCl2 dissolved in proportionately small volumes of HCI (0.3%), in the reduction of a 99mTcO4- eluted from a 99Mo generator.

[Community-acquired respiratory infections]. / Estudio de las infecciones respiratorias extrahospitalarias.

BACKGROUND: Respiratory infections are the most frequent reason for primary health care consultation. Although generally not severe, they are responsible for a large number of days of laboral and scholar absenteeism and an excessive use of antibiotics. METHODS: The clinical and epidemiologic data of extrahospitalary infections in primary health care centers throughout Spain were collected according to the one day cut off system repeated trimestrally over one year. RESULTS: Data of 3,732 days of consultation were collected in which a total of 144,608 patients were attended. Of these, 20,614 had respiratory infections and 11,684 extrarespiratory infections. The most frequent processes were pharyngitis (33.7%), common cold (31.7%) followed by bronchitis (18.7%), otitis (11%), influenza (4.6%), laryngitis (4%), sinusitis (3.6%) and pneumonia (1.8%). Antibiotic treatment was prescribed in 13,488 patients (65%). The type of antibiotic was analyzed in the 11,977 patients treated for only one infection. Penicillins were the antibiotics most used followed by cephalosporins. The antibiotic prescribed was considered adequate in 70% of the 8,484 patients treated for potentially bacterial infection. A total of 3,493 patients had infection considered to be of viral etiology. CONCLUSIONS: Twenty-two percent of the patients attending a primary health care center presented infection and of these two out of three cases had respiratory infection. Pharyngitis and common cold were the most frequent processes observed. Two thirds of the patients consulting for respiratory infection received antibiotic treatment, with 29.2% being diagnosed with infections considered to be of viral etiology. The empiric treatment chosen for the two thirds of the potentially bacterial infections was considered as adequate.