Production study of Fr, Ra and Ac radioactive ion beams at ISOLDE, CERN.

The presented paper discusses the production of radioactive ion beams of francium, radium, and actinium from thick uranium carbide (UC x ) targets at ISOLDE, CERN. This study focuses on the release curves and extractable yields of francium, radium and actinium isotopes. The ion source temperature was varied in order to study the relative contributions of surface and laser ionization to the production of the actinium ion beams. The experimental results are presented in the form of release parameters. Representative extractable yields per µ C are presented for 222 - 231 Ac, several Ra and Fr isotopes in the mass ranges 214 ≤ A ≤ 233 and 205 ≤ A ≤ 231 respectively. The release efficiency for several isotopes of each of the studied elements was calculated by comparing their yields to the estimated in-target production rates modeled by CERN-FLUKA. The maximal extraction efficiency of actinium was calculated to be 2.1(6)% for a combination of surface ionization using a Ta ion source and resonant laser ionization using the two-step 438.58 nm, and 424.69 nm scheme.

Half-life determination of 155Tb from mass-separated samples produced at CERN-MEDICIS.

Terbium-155 has been identified for its potential for single-photon emission computed tomography (SPECT) in nuclear medicine. For activity measurements, an accurate and precise half-life of this radionuclide is required. However, the currently evaluated half-life of 5.32(6) d with a relative standard uncertainty of 1.1% determines the precision possible. Limited literature for the half-life measurements of this radionuclide is available and all reported investigations are prior to 1970. Further measurements are therefore needed to confirm the accuracy and improve the precision of the half-life for its use in the clinical setting. Two samples produced and mass separated at the CERN-MEDICIS facility have been measured at the National Physical Laboratory by two independent techniques: liquid scintillation counting and high-purity germanium gamma-ray spectrometry. A half-life of 5.2346(36) d has been determined from the weighted mean of the half-lives determined by the two techniques. The half-life reported in this work has shown a relative difference of 1.6% to the currently evaluated half-life and has vastly improved the precision.

Achievement of effective cardiopulmonary trauma surgical skills training throughout the incorporation of a low-cost and easy to implement pulsatile simulation model.

OBJECTIVES: . In the last decade, concern regarding the preparedness of general surgery graduates to effectively manage thoracic trauma cases has been raised. However, due to limited availability and elevated costs, access to cardiopulmonary trauma simulation models is limited. This article describes our experience implementing a low-cost blended ex vivo tissue-based simulation model using animal by-products that incorporates pump perfusion and ventilation. DESIGN: . Firstly, for validation purposes 8 junior residents, 8 recently graduated general surgeons, and 3 cardiothoracic surgery attendings from Pontificia Universidad Católica de Chile Clinical Hospital were recruited. Proficiency in performing a pulmonary tractotomy and a myocardial injury repair was assessed with global and specific rating scales. Secondly, to evaluate the effectiveness of the model as a learning tool, 16 general surgery residents from different programs across the country were recruited receiving intensive, personalized training on the models. Proficiency was measured before and after the training. RESULTS: . For the validation phase, significant differences among groups according to the previous level of expertise were shown, and therefore construct validity was established. The results of the second phase showed a significant overall improvement in participant's performance. CONCLUSION: . Effective training and assessment for advanced surgical skills in cardiothoracic trauma can be achieved using a low-cost pulsatile simulation model.

Genotoxicity effects on Geophagus brasiliensis fish exposed to Doce River water after the environmental disaster in the city of Mariana, MG, Brazil / Efeitos da genotoxicidade em peixes da espécie Geophagus brasiliensis expostos a água do Rio Doce após o desastre ambiental na cidade de Marina, MG, Brasil

Abstract The Doce River basin has suffered the largest environmental accident ever occurred in Brazil with the influx of tailings from Fundão and Santarém, belonging to Samarco mining company, due to the disaster in Mariana. A spill between 50 and 60 million m3 of tailings was estimated by the company. According to Samarco, the wastewater was composed mainly of clay, silt and heavy metals like iron, copper and manganese. Thereby, the objective of the present study was evaluated the genotoxic damage in juvenile of Geophagus brasiliensis (Quoy e Gaimard, 1824) exposed to Doce river water before (DRWBA - Doce River water before acident) and after (DRWAA - Doce River water after acident) the influx of tailings from the Germano and Santarém Dam disasters in Mariana, MG, Brazil. For this, 24 individuals of the species G. brasiliensis (obtained on IFES/ALEGRE fish culture) were submitted to a bioassay with three treatments and eight replicates. The treatments were: 1) Control water (water from the urban water supply system, filtered with a 0.45 µm membrane), 2) DRBA and 3) DRAA. After 96 h, these fishes were anesthetized to remove blood for evaluation of genotoxic damage (micronucleus and comet). For the bioassay, a total of 80 L of The Doce River water were collected before the influx of tailings and after the influx and then submitted to metal quantification analysis. Fish exposed to DRWBA and DRWAA treatments showed a significant increase in both the number of erythrocyte micronuclei and the DNA damage index in relation to the control fish; however, they did not present any differences between the two treatments. The results demonstrate that the DRWBA treatment was already genotoxic for the fish, mainly due to dissolved Cu concentrations in the water. The DRWAA treatment probably presented genotoxicity due to the increase in the dissolved fraction and synergistic effects of several metals found in the tailings of the Mariana accident.

Resumo A bacia do Rio Doce sofreu o maior acidente ambiental com o influxo de rejeitos de Fundão e Santarém, pertencentes à empresa de mineração Samarco, devido ao desastre em Mariana. Um derramamento entre 50 e 60 milhões de m3 de rejeitos foi estimado pela empresa. De acordo com a Samarco, o rejeito despejado era composto principalmente de argila, silte e alguns metais pesados como ferro, cobre e manganês. Com isso, o presente estudo teve como objetivo avaliar os danos genotóxicos em juvenis de Geophagus brasilienses expostos a água do rio Doce antes (DRWAA - água do Rio Doce antes do acidente) e depois (DRWBA- água do Rio Doce depois do acidente) da chegada dos rejeitos do rompimento das barragens de Germano e Santarém em Mariana, MG, Brasil. Para isso, 24 indivíduos da espécie G. brasilienses (obtidos na piscicultura do IFES/ALEGRE) foram submetidos a um bioensaio com três tratamentos e oito réplicas. Os tratamentos eram: 1) Controle (com água do abastecimento urbano, filtrada com filtro analítico de 0,45 µm); 2) DRWBA e 3) DRWAA. Após um período de 96 h, esses peixes foram anestesiados para retirada de sangue para avaliação dos danos genotóxicos (micronúcleo e cometa). Para a realização do bioensaio, um total de 80 L de água do Rio Doce foram coletados antes da chegada dos rejeitos e outros 80 L foram coletados depois da chegada dos rejeitos e ambas foram submetidas a análises de quantificação de metal. Os peixes expostos ao DRWBA e ao DRWAA apresentaram um aumento significativo na quantidade de micronúcleos eritrocitários e no índice de danos do DNA em relação aos peixes controle, no entanto não apresentaram diferenças entre si. Os resultados obtidos demonstram que a DRWBA já era genotóxica para os peixes, principalmente, em função das concentrações de Cu dissolvido na água. A DRWAA apresentou genotixicidade, provavelmente, em função do aumento da fração dissolvida e do efeito sinérgico de diversos metais presentes nos rejeitos do acidente de Mariana.

Percolation behaviors of ionic and electronic transfers in Li3-2xCoxN.

Nitridocobaltates Li3-2xCoxN, with Li3N-type layered structure, are promising compounds as negative electrode materials for Li-ion batteries. In the present paper, we report the first detailed broadband dielectric spectroscopy (BDS) study on lithiated transition metal nitrides. The ionic and electronic conductivities of Li3-2xCox□xN compounds (0 ≤ x ≤ 0.44) are investigated as a function of the concentration x of cobalt ions, cationic vacancies (□) and lithium ions. Dielectric and conductivity spectra were recorded within the frequency range of 60-1010 Hz from 200 to 300 K. Experimental results exhibit two types of electric conduction: the first one is due to lithium ion diffusion (for 0 ≤ x ≤ 0.25) and the second one due to electronic transfers (for x ≥ 0.3). Furthermore, two percolation transitions are evidenced and associated with 3D ionic transfers (threshold at x ≈ 0.11) on the one hand and 2D electronic transfers (threshold at x ≈ 0.30) on the other hand. Upon increasing the frequency, dielectric relaxations appear from larger to smaller sample scales. These successive polarizations appear with increasing frequency in the following order: (a) sample/silver paint interface; (b) particles (aggregates of grains); (c) grains (crystallites); (d) local ionic and electronic motions within the grains. Evolutions of dielectric relaxation parameters (dielectric strength and relaxation frequency) with Co content confirm the two percolation transitions. Surprisingly, the grain conductivity has a large discontinuity immediately below the electronic percolation threshold where any local- and long-range ionic movement disappears without electronic transfer. This discontinuity would be due to a narrow transition from ionic to electronic conduction when x increases.

Genotoxicity effects on Geophagus brasiliensis fish exposed to Doce River water after the environmental disaster in the city of Mariana, MG, Brazil.

The Doce River basin has suffered the largest environmental accident ever occurred in Brazil with the influx of tailings from Fundão and Santarém, belonging to Samarco mining company, due to the disaster in Mariana. A spill between 50 and 60 million m3 of tailings was estimated by the company. According to Samarco, the wastewater was composed mainly of clay, silt and heavy metals like iron, copper and manganese. Thereby, the objective of the present study was evaluated the genotoxic damage in juvenile of Geophagus brasiliensis (Quoy e Gaimard, 1824) exposed to Doce river water before (DRWBA - Doce River water before acident) and after (DRWAA - Doce River water after acident) the influx of tailings from the Germano and Santarém Dam disasters in Mariana, MG, Brazil. For this, 24 individuals of the species G. brasiliensis (obtained on IFES/ALEGRE fish culture) were submitted to a bioassay with three treatments and eight replicates. The treatments were: 1) Control water (water from the urban water supply system, filtered with a 0.45 µm membrane), 2) DRBA and 3) DRAA. After 96 h, these fishes were anesthetized to remove blood for evaluation of genotoxic damage (micronucleus and comet). For the bioassay, a total of 80 L of The Doce River water were collected before the influx of tailings and after the influx and then submitted to metal quantification analysis. Fish exposed to DRWBA and DRWAA treatments showed a significant increase in both the number of erythrocyte micronuclei and the DNA damage index in relation to the control fish; however, they did not present any differences between the two treatments. The results demonstrate that the DRWBA treatment was already genotoxic for the fish, mainly due to dissolved Cu concentrations in the water. The DRWAA treatment probably presented genotoxicity due to the increase in the dissolved fraction and synergistic effects of several metals found in the tailings of the Mariana accident.

Effects of cytochalasin E on Paracoccidioides brasiliensis.

AIMS: To determine the effects of cytochalasin E, isolated from the extremophile fungus Aspergillus felis, on the cells of Paracoccidioides brasiliensis Pb18. METHODS AND RESULTS: Cytochalasin E showed a minimal inhibitory concentration of 3·6 µmol l-1 and minimum fungicidal concentration of 7·2 µmol l-1 on P. brasiliensis by in vitro microdilution and IC50 >964·0 µmol l-1 on murine macrophages. Its selectivity index (>263) indicated that this compound has selectivity for fungal cells. Morphological alterations were determined by optical and fluorescence microscopy, as well as scanning and transmission electron microscopy. Cytochalasin E affected P. brasiliensis bud-forming pseudohyphae, cell morphology, cell walls and cell membranes; caused the release of cellular material; and resulted in the production of reactive oxygen species. In murine macrophages, it affected cytoskeletal actin and inhibited phagocytosis. CONCLUSION: Cytochalasin E may be useful as an antifungal prototype against P. brasiliensis and in studies on phagocytosis. SIGNIFICANCE AND IMPACT OF THE STUDY: Paracoccidioides spp. are the etiological agents of paracoccidioidomycosis (PCM). Treatment is prolonged to control the clinical manifestations and prevent relapse. The study on the effects of cytochalasin E in P. brasiliensis is important because it can be used as a prototype for new antifungal drugs and consequently, broadens the treatment options for PCM.

Levels of neutral detergent fiber in diets with forage palm for dairy goats / Fibra em detergente neutro em dietas com palma forrageira para cabras leiteiras

This study aimed to evaluate the amount of fiber in the diet that is able to promote better use of nutrients in the diet of dairy goats when forage palm is the main source of roughage. Fifteen Alpine dairy goats were distributed in a 5 × 5 triple Latin square containing five treatments and five periods, and each treatment contained. We tested five diets composed of different contents of neutral detergent fiber from Tifton hay (NDFf) in the dry matter of rations containing forage palm: D1: 11.98%; D2: 18.31%; D3: 23.68%; D4: 28.76% and D5: 32.12% NDFf. The intake of dry matter, crude protein, neutral detergent fiber, non-fiber carbohydrates and ether extract decreased linearly with the increase in NDFf content. There was a linear increase of milk production and milk protein with increasing dietary NDFf. The fat, dry extract, protein, pH and acidity of the evaluated milk were not affected by increasing the levels of NDFf in the diet. In situations where dairy goats are fed forage palm and other types of forage are limited, 11.98% NDF from forage other than palm can be used as an effective source of NDF.(AU)

Objetivou-se, com este trabalho, avaliar a quantidade de fibra na dieta que é capaz de promover melhor uso de nutrientes na dieta de cabras leiteiras quando a palma forrageira é a principal fonte de forragem. Quinze cabras leiteiras alpinas foram distribuídas em um quadrado latino triplo 5 × 5 contendo cinco tratamentos e cinco períodos. Testaram-se cinco dietas compostas por diferentes teores de fibra em detergente neutro de feno de tifton (FDNf) na matéria seca de rações contendo palma forrageira: D1: 11,98%; D2: 18,31%; D3: 23,68%; D4: 28,76% e D5: 32,12% de FDNf. A ingestão de matéria seca, proteína bruta, fibra em detergente neutro, carboidratos não fibrosos e extrato etéreo diminuiu linearmente com o aumento do conteúdo de FDNf. Houve um aumento linear da produção de leite e da proteína do leite com o aumento da FDNf dietética. A gordura, a lactose, o extrato seco, o pH e a acidez do leite não foram afetados pelo aumento dos níveis de FDNf na dieta. Em situações em que as cabras leiteiras são alimentadas com palma forrageira e outros tipos de forragem são limitados, 11,98% de FDN de forragem diferente da palma podem ser usados como fonte efetiva de fibra.(AU)

Qualidade da carne de ovinos terminados em confinamento com dietas com silagens de diferentes cultivares de sorgo / Meat quality of finishing feedlot lambs fed diets of assorted sorghum cultivars

Objetivou-se avaliar a influência de dietas contendo silagem de diferentes cultivares de sorgo sobre as características físicas e químicas na carne de ovinos sem padrão racial definido, com idade entre cinco e sete meses e peso vivo médio de 17,7±3,7kg, alimentados com dietas contendo silagem de diferentes cultivares de sorgo. O experimento foi conduzido na Estação Experimental Pendência, pertencente à Empresa Estadual de Pesquisa Agropecuária - Emepa, tendo um período experimental de 42 dias. Utilizou-se um delineamento inteiramente ao acaso, com cinco tratamentos (silagem de sorgo BRS 610, BRS 655, BRS 800, BRS 810 e Ponta Negra) e sete repetições. Ao atingirem o peso de abate de 26,24kg, os animais foram encaminhados ao abate. Procedeu-se à análise do pH, da cor, da perda de peso por cocção, da força de cisalhamento, bem como à determinação de umidade, proteínas, cinzas e lipídeos totais no músculo Longissimus dorsi. As dietas não influenciaram os parâmetros de pH (5,64), cor (L*23,13, a* 18,00, b*15,78), perdas de peso por cocção (34,43%), umidade (72,53%), proteína (24,08%), cinzas (1,09%) e lipídeos (2,99%). A força de cisalhamento diferiu entre as dietas, com a silagem do cultivar BRS 655 propiciando uma carne mais macia (2,10kgf/cm2). As silagens de sorgo utilizadas na confecção das dietas de cordeiros em confinamento não interferem nas características de qualidade da carne de ovinos sem padrão racial definido. Dietas contendo silagem de sorgo granífero BRS 655 proporcionaram uma carne mais macia.(AU)

This study aimed to evaluate the influence of diets containing silage of different sorghum cultivars on the physical and chemical characteristics in the meat of lambs. Thirty five animals of undefined breed with average age between 5 and 7 months and average body weight of 17. 7±3.7kg were used. The lambs were randomly assigned to five treatments (sorghum silage BRS 610, BRS 655, BRS 800, BRS 810 e Ponta Negra) with seven replicates. When they reach 26.24kg of weight, the animals were sent to be slaughtered. Proceeded to the analysis of pH, color, cooking losses, shear force, determination of humidity, protein, ash and total amount of lipids in the Longissimus dorsi. The diets did not influence the parameters of pH (5.64), color (L*23.13, a* 18.00, b*15.78), cooking losses (34.43%), humidity (72.53%), protein (24.08%), ash (1.09%) or lipids (2.99%). The shear force differed among the diets, with the silage of cultivar BRS 655 providing a tender meat (2.10kgf/cm2). The sorghum silages used in in the diets did not interfere in the meat quality characteristics of feedlot lambs. Diets containing sorghum grain silage BRS 655 provided a tender meat.(AU)

Unravelling redox processes of Li7MnN4 upon electrochemical Li extraction-insertion using operando XAS.

A large data set of XAS (X-ray Absorption Spectroscopy) Manganese K-edge spectra has been collected operando and studied upon the electrochemical oxidation of the promising Li-ion battery anode material Li7MnN4. Using chemometric tools such as PCA (Principal Component Analysis) and MCR-ALS (Multivariate Curve resolution - Alternating Least Squares), three independent environment spectra were insulated. Based on the faradaic yield and well-chosen comparison of absorption spectrum energies within the frame of the coordination charge model, these environments were ascribed to unusual oxidation states allowed by nitride chemistry at a low potential (∼1.2 V vs. Li+/Li), i.e. Mn5+ (3d2), Mn6+ (3d1) and Mn7+ (3d0). Also, their relative amounts are discussed with regard to the long-range structural variation which can be simply described by two successive biphasic domains followed by a solid-solution behaviour. Gathering this long-range and local structure information provides a complete picture of the redox mechanisms occurring in Li7MnN4.

Genotoxicity effects on Geophagus brasiliensis fish exposed to Doce River water after the environmental disaster in the city of Mariana, MG, Brazil

Abstract The Doce River basin has suffered the largest environmental accident ever occurred in Brazil with the influx of tailings from Fundão and Santarém, belonging to Samarco mining company, due to the disaster in Mariana. A spill between 50 and 60 million m3 of tailings was estimated by the company. According to Samarco, the wastewater was composed mainly of clay, silt and heavy metals like iron, copper and manganese. Thereby, the objective of the present study was evaluated the genotoxic damage in juvenile of Geophagus brasiliensis (Quoy e Gaimard, 1824) exposed to Doce river water before (DRWBA Doce River water before acident) and after (DRWAA Doce River water after acident) the influx of tailings from the Germano and Santarém Dam disasters in Mariana, MG, Brazil. For this, 24 individuals of the species G. brasiliensis (obtained on IFES/ALEGRE fish culture) were submitted to a bioassay with three treatments and eight replicates. The treatments were: 1) Control water (water from the urban water supply system, filtered with a 0.45 µm membrane), 2) DRBA and 3) DRAA. After 96 h, these fishes were anesthetized to remove blood for evaluation of genotoxic damage (micronucleus and comet). For the bioassay, a total of 80 L of The Doce River water were collected before the influx of tailings and after the influx and then submitted to metal quantification analysis. Fish exposed to DRWBA and DRWAA treatments showed a significant increase in both the number of erythrocyte micronuclei and the DNA damage index in relation to the control fish; however, they did not present any differences between the two treatments. The results demonstrate that the DRWBA treatment was already genotoxic for the fish, mainly due to dissolved Cu concentrations in the water. The DRWAA treatment probably presented genotoxicity due to the increase in the dissolved fraction and synergistic effects of several metals found in the tailings of the Mariana accident.

Resumo A bacia do Rio Doce sofreu o maior acidente ambiental com o influxo de rejeitos de Fundão e Santarém, pertencentes à empresa de mineração Samarco, devido ao desastre em Mariana. Um derramamento entre 50 e 60 milhões de m3 de rejeitos foi estimado pela empresa. De acordo com a Samarco, o rejeito despejado era composto principalmente de argila, silte e alguns metais pesados como ferro, cobre e manganês. Com isso, o presente estudo teve como objetivo avaliar os danos genotóxicos em juvenis de Geophagus brasilienses expostos a água do rio Doce antes (DRWAA água do Rio Doce antes do acidente) e depois (DRWBA- água do Rio Doce depois do acidente) da chegada dos rejeitos do rompimento das barragens de Germano e Santarém em Mariana, MG, Brasil. Para isso, 24 indivíduos da espécie G. brasilienses (obtidos na piscicultura do IFES/ALEGRE) foram submetidos a um bioensaio com três tratamentos e oito réplicas. Os tratamentos eram: 1) Controle (com água do abastecimento urbano, filtrada com filtro analítico de 0,45 µm); 2) DRWBA e 3) DRWAA. Após um período de 96 h, esses peixes foram anestesiados para retirada de sangue para avaliação dos danos genotóxicos (micronúcleo e cometa). Para a realização do bioensaio, um total de 80 L de água do Rio Doce foram coletados antes da chegada dos rejeitos e outros 80 L foram coletados depois da chegada dos rejeitos e ambas foram submetidas a análises de quantificação de metal. Os peixes expostos ao DRWBA e ao DRWAA apresentaram um aumento significativo na quantidade de micronúcleos eritrocitários e no índice de danos do DNA em relação aos peixes controle, no entanto não apresentaram diferenças entre si. Os resultados obtidos demonstram que a DRWBA já era genotóxica para os peixes, principalmente, em função das concentrações de Cu dissolvido na água. A DRWAA apresentou genotixicidade, provavelmente, em função do aumento da fração dissolvida e do efeito sinérgico de diversos metais presentes nos rejeitos do acidente de Mariana.

Lattice dynamics of ß-V2O5: Raman spectroscopic insight into the atomistic structure of a high-pressure vanadium pentoxide polymorph.

We report here the Raman spectrum and lattice dynamics study of a well-crystallized ß-V(2)O(5) material prepared via a high-temperature/high-pressure (HT/HP) route, using α-V(2)O(5) as the precursor. Periodic quantum-chemical density functional theory calculations show good agreement with the experimental results and allow one to assign the observed spectral features to specific vibrational modes in the ß-V(2)O(5) polymorph. Key structure-spectrum relationships are extracted from comparative analysis of the vibrational states of the ß-V(2)O(5) and α-V(2)O(5) structures, and spectral patterns specific to the basic units of the two V(2)O(5) phases are proposed for the first time. Such results open the way for the use of Raman spectroscopy for the structural characterization of vanadium oxide-based host lattices of interest in the field of lithium batteries and help us to greatly understand the atomistic mechanism involved in the α-to-ß phase transition of vanadium pentoxide.

Modulation filtering for noise detection in heart sound signals.

Cardiac auscultation has proven to be an excellent diagnostic tool. Heart sound processing algorithms are not completely robust in the presence of noise, requiring clean segments of heart sounds to extract reliable diagnostic features. This paper presents a new approach to detect transient noises mixed with heart sound. The algorithm explores a single channel source separation algorithm and evaluates the non-stationary separated signals. It has the potential to be applied in real-time. Using a database of heart sounds acquired in real-life scenario, the method showed a sensitivity and a specificity of 93.6% and 92.3%, respectively.

Heteroduplex mobility assay of the D1/D2 region of the 26S rDNA for differentiation of Saccharomyces species.

AIMS: We present the HMA method for Saccharomyces differentiation using the PCR amplified D1/D2 26S rDNA. METHODS AND RESULTS: This methodology is based on heteroduplex formation when two different DNAs are hybridized. We tested 11 type cultures of Saccharomyces, 27 different cultures of S. cerevisiae and four other ascomycetic genera. CONCLUSION: The method was capable of differentiating Saccharomyces species and was mainly very efficient for S. cerevisiae identification. HMA can probably be applied in other genera, where identification is sometimes difficult only by conventional traits, which are based on physiology and morphology. SIGNIFICANCE AND IMPACT OF THE STUDY: HMA provides a rapid and relatively simple molecular tool, contributing for yeast taxonomy.

Microemulsion cyclosporin formulation, in contrast to the old formulation, widens the T lymphocyte subsets differences between stable and acute rejection of kidney transplants.

BACKGROUND: The new cyclosporin (CsA) formulation, Neoral, has different pharmacokinetics compared with Sandimmune (SIM). Larger area under the curve (AUC) values with equivalent trough blood values are reached when Neoral is administered at equivalent doses to SIM. Previously, we showed a great diagnostic reliability when using cytofluorometric analysis from fine-needle aspiration biopsy (FNAB) samples. We investigated possible changes brought about by Neoral on lymphocyte subsets and the repercussions on the activation score cut-off for acute rejection, defined under SIM treatment. METHODS: Of 63 patients that received SIM, 40 remained rejection-free and 23 suffered one episode of rejection. Of 52 patients that received Neoral, 38 remained rejection-free. Peripheral blood lymphocytes (PBL) and lymphocytes from FNAB taken on days 7 and 14 post-transplantation and on the first day of acute rejection were analysed by flow cytometry. RESULTS: Trough blood CsA levels were not different between SIM and Neoral treatments. Among rejection-free patients, a significant down-regulation of CD3DR and of CD8DR expression on both graft-infiltrating lymphocytes (GIL) and PBL, and significant up-regulation of naïve T cells on GIL were observed with Neoral. These changes were followed by a significant down-regulation of the activation score with Neoral. Conversely, within the acute rejection group, the activation score was significantly higher with Neoral than with SIM. The activation score performed equally well in Neoral transplants compared with what we had reported with SIM. CONCLUSIONS: Our study indicates that Neoral elicits stronger immunosuppressive effects in stable patients, which eventually should translate into better clinical efficiency. However, when acute rejection supervenes, the treatment breakthrough seems stronger with Neoral. Cytofluorometric studies from FNAB samples showed that diagnostic reliability was maintained at a high level under Neoral therapy.

Sequencing as a tool in yeast molecular taxonomy.

The literature on sequencing as a tool for yeast molecular taxonomy is reviewed. Ribosomal DNA has been preferred for sequencing over other molecules such as mitochondrial DNA, and a large database is now available. rDNA consists of regions that evolve at different rates, allowing comparison of different levels of relationship among yeasts. Sequences of the 18S rDNA and the 25S rDNA have been largely used for yeast systematics and phylogeny, but the search for regions with increased resolving power has led to the study of the spacer regions of the rDNA. Few studies are concerned with signature sequences.

T lymphocyte subsets and cytokine production by graft-infiltrating cells in FSGS recurrence post-transplantation.

BACKGROUND: Focal segmental glomerulosclerosis (FSGS) aetiology remains undefined although a derangement of lymphocytes and monocytes macrophages, at least, has been strongly suspected. We report the graft-infiltrating phenotypes and their cytokine production in a case of FSGS recurrence post-transplantation. METHODS: The kidney transplant recipient suffered immediate FSGS recurrence. Aspiration biopsies were done at the first and second week post-surgery and were analysed by flow cytometry. The cytokine analysis was done on aspiration sample culture supernatants and serum by enzyme-linked immunosorbent assay. RESULTS: High expression of CD3CD69, CD3CD71 and CD4CD29 was found on infiltrating lymphocytes. Biopsy cultures pointed to a Th0/Th1 pattern of cytokine production as well as significant synthesis of transforming growth factor-beta1. Interestingly, monocyte chemokines were absent. CONCLUSION: We report evidence of intragraft lymphocyte activation in the early days of FSGS recurrence. Aspiration biopsy cultures showed failure of cyclosporin A to inhibit interleukin-2 (IL-2) production by infiltrating lymphocytes. If our findings are confirmed in similar patients, a trial with anti-IL-2-receptor antibody could be warranted.

Analysis of fine-needle aspiration biopsies by flow cytometry in kidney transplant patients.

BACKGROUND: Peripheral blood lymphocyte (PBL) analysis by flow cytometry has been inconsistently reported as an adjunctive method for diagnosing acute kidney transplant rejection. However, there is good evidence that lymphocytes infiltrating renal grafts differ from those found at the peripheral level. We hypothesized that the study of aspiration biopsy samples in conjunction with PBL by flow cytometry would enable us to diagnose acute rejection crisis reliably. METHODS: Lymphocytes from PBL and aspiration biopsies of kidney transplant patients were analyzed. Fifty-one stable patients, rejection-free for the first 6 months, were studied on day 7 and day 30 after transplantation and were compared with 32 patients with 40 acute rejection episodes. RESULTS: Significant differences were observed for several lymphocyte subpopulations on aspiration biopsy samples comparing stable patients with rejection patients. In contrast, PBL analysis was not helpful in differentiating the two groups of patients. By combining the expression of several activation markers inside the graft with CD3DR and CD3CD25 aspiration biopsy to peripheral blood ratios, we obtained very good values for sensitivity and specificity-83.9% and 90.5%, respectively. The positive predictive value for rejection among dysfunctional grafts reached 85.8%. CONCLUSIONS: Flow cytometry study of aspiration biopsy samples of kidney transplant patients is a reliable and powerful method to diagnose acute rejection episodes, although it is needed to consider several lymphocyte phenotypes; cytofluorometric analysis of PBL is important because it provides graft-infiltrating cell to peripheral blood lymphocyte ratios. This safe and rapid test may significantly improve the management of kidney transplant patients.

[Rate of protein catabolism as an indicator of protein ingestion in uremic patients on hemodialysis]. / Tasa de catabolismo proteico como indicador de la ingesta proteica en pacientes urémicos en hemodiálisis.

Protein catabolic rate (PCR) has been proposed as a indirect index of dietary protein intake, but its sensitivity has been discussed. In a group of 140 chronic uremic patients undergoing maintenance hemodialysis, we evaluated the nutritional status (body mas index: BMI, triceps skinfold thickness: TST, arm muscle circumference: AMC, serum total proteins, albumin and lymphocytes) and its relation with dietary survey and PCR levels. PCR was correlated positively with Kt/V (p: 0.0001, r: 0.45) and with seric albumin (p: 0.01, r: 0.22), whereas dietary protein intake by dietary survey (g/Prot/Kg/day) was correlated strongly with anthropometric measurements like BMI, AMC (p: 0.0001) and less with Kt/V (p: 0.01), but not with serum albumin. PCR was correlated with dietary survey results: g Prot/Kg/day (p: 0.04, r: 0.18) and Kcal/Kg/day (p: 0.03, r:0.2). The results suggest that nutritional parameters with slow evolution as anthropometric measurements could be related with usual dietary intake (dietary survey), whereas serum albumin (that vary early with recent changes of dietary intake) could be related better with a biochemical index like PCR, in these way both determinations are complementary.