Influence of dissolution on the uptake of bimetallic nanoparticles Au@Ag-NPs in soil organism Eisenia fetida.

A key aspect in the safety testing of metal nanoparticles (NPs) is the measurement of their dissolution and of the true particle uptake in organisms. Here, based on the tendency of Ag-NP to dissolve and Au-NP to be inert in the environment, we exposed the earthworm Eisenia fetida to Au core-Ag shell NPs (Au@Ag-NPs, Ag-NPs with a Au core) and to both single and combined exposures of non-coated Au-NPs, Ag-NPs, Ag+ and Au+ ions in natural soil. Our hypothesis was that the Ag shell would partially or completely dissolve from the Au@Ag-NPs and that the Au core would thereby behave as a tracer of particulate uptake. Au and Ag concentrations were quantified in all the soils, in soil extract and in organisms by inductively coupled plasma mass spectrometry (ICP-MS). The earthworm exposed to Au@Ag-NPs, and to all the combinations of Ag and Au, were analyzed by single particle inductively coupled plasma time-of-flight mass spectrometry (spICP-TOFMS) to allow the quantification of the metals that were truly part of a bimetallic particle. Results showed that only 5% of the total metal amounts in the earthworm were in the bimetallic particulate form and that the Ag shell increased in thickness, suggesting that biotransformation processes took place at the surface of the NPs. Additionally, the co-exposure to both metal ions led to a different uptake pattern compared to the single metal exposures. The study unequivocally confirmed that dissolution is the primary mechanism driving the uptake of (dissolving) metal NPs in earthworms. Therefore, the assessment of the uptake of metal nanoparticles is conservatively covered by the assessment of the uptake of their ionic counterpart.

Impact of Ag2S NPs on soil bacterial community - A terrestrial mesocosm approach.

Soils might be a final sink for Ag2S nanoparticles (NPs). Still, there are limited data on their effects on soil bacterial communities (SBC). To bridge this gap, we investigated the effects of Ag2S NPs (10 mg kg-1 soil) on the structure and function of SBC in a terrestrial indoor mesocosm, using a multi-species design. During 28 days of exposure, the SBC function-related parameters were analysed in terms of enzymatic activity, community level physiological profile, culture of functional bacterial groups [phosphorous-solubilizing bacteria (P-SB) and heterotrophic bacteria (HB)], and SBC structure was analysed by 16S rRNA gene-targeted denaturing gradient gel electrophoresis. The SBC exposed to Ag2S NPs showed a significative decrease of functional parameters, such as ß-glucosidase activity and L-arginine consumption, and increase of the acid phosphatase activity. At the structural level, significantly lower richness and diversity were detected, but at later exposure times compared to the AgNO3 treatment, likely because of a low dissolution rate of Ag2S NPs. In fact, stronger effects were observed in soils spiked with AgNO3, in both functional and structural parameters. Changes in SBC structure seem to negatively correlate with parameters related to phosphorous (acid phosphatase activity) and carbon cycling (abundance of HB, P-SB, and ß-glucosidase activity). Our results indicate a significant effect of Ag2S NPs on SBC, specifically on parameters related to carbon and phosphorous cycling, at doses as low as 10 mg kg-1 soil. These effects were only observed after 28 days, highlighting the importance of long-term exposure experiments for slowly dissolving NPs.

Combined liver-kidney transplantation in patients with cirrhosis and chronic kidney disease.

The outcome of patients with cirrhosis and chronic kidney disease treated with combined liver-kidney transplantation (CLKT) is not well known because most series of patients treated with CLKT include not only patients with cirrhosis but also patients with inherited diseases without cirrhosis. To evaluate to what extent the combined kidney transplantation impairs posttransplantation outcome compared to liver transplantation (LT) alone, the outcome of patients with cirrhosis and chronic kidney disease treated with CLKT (n = 20) was compared to that of a group of patients with cirrhosis without chronic kidney disease treated with LT alone matched by age, sex, year of transplantation and severity of cirrhosis (n = 60). The primary end point of the study was survival, and secondary end points were outcome of renal function and complications within 6 months of transplantation. Patients with CLKT had a higher incidence of bacterial infections and transfusion requirements compared to LT patients. The incidence of acute renal failure during the first 6 months was similar, yet the severity of renal failure was greater in patients with CLKT. Hospital and intensive care unit (ICU) stays were longer in the CLKT group. One- and three-year survival probabilities in patients treated with CLKT were 80 and 75% compared to 97 and 88%, respectively, in patients treated with LT. In conclusion, CLKT for patients with cirrhosis and chronic kidney disease is associated with a relatively high frequency of postoperative complications that moderately impairs short-term survival. However, 3-year survival of patients with cirrhosis treated with CLKT is excellent.

Hyponatremia is a risk factor of hepatic encephalopathy in patients with cirrhosis: a prospective study with time-dependent analysis.

OBJECTIVES: The aim of this study was to investigate whether hyponatremia is a risk factor of overt hepatic encephalopathy (HE) in cirrhosis. METHODS: A total of 61 patients with cirrhosis were evaluated prospectively for 1 year and all episodes of overt HE were recorded. Predictive factors of HE were analyzed using a conditional model (Prentice, Williams, and Peterson) for recurrent events to assess the relationship between HE and time-dependent covariates. The effects of hyponatremia on the brain concentration of organic osmolytes were analyzed in 25 patients using 1 H-magnetic resonance spectroscopy. RESULTS: Twenty-eight of the 61 patients developed 57 episodes of overt HE during follow-up. Among a number of clinical and laboratory variables analyzed, the only independent predictive factors of overt HE were hyponatremia (serum sodium < 130 mEq / l), history of overt HE, serum bilirubin,and serum creatinine. Hyponatremia was associated with low brain concentration of organic osmolytes, particularly myo-inositol (MI). Furthermore, patients with low brain MI levels had a higher probability of development of overt HE compared with that of patients with high brain MI levels. CONCLUSIONS: In patients with cirrhosis, the existence of hyponatremia is a major risk factor of the development of overt HE. Treatment of hyponatremia may be a novel therapeutic approach to preventing HE in cirrhosis.

Histopathological and ultrastructural characteristics of myeloid leukosis in broiler chicken

An ultrastructural and histological study was performed to determine the degree of differentiation of the neoplastic cells. The histological study revealed neoplastic cells with pleomorphism, oval nuclei, prominent nucleoli, irregularly distributed chromatin, atypical mitotic figures and moderate amount of cytoplasm containing spherical eosinophilic granulations, typical features of the myeloid lineage. Ultrastructurally, there were cells with an electron-dense, oval and voluminous nucleus, with predominant euchromatin and cytoplasm containing many spherical, electron-dense and homogeneous granules, indicative of myelocytes with differentiation to eosinophils. Type-C viral particles were also seen in the intercellular space of renal tubules and inside the intracytoplasmic vesicles of immature myelocytes in the bone marrow and ovary. PCR was positive to ALV-J.

Caracterizaram-se a linhagem e o grau de diferenciação das células neoplásicas no estudo histopatológico e ultraestrutural da leucose mielóide. Histologicamente as células neoplásicas apresentaram pleomorfismo, núcleos ovais, nucléolos proeminentes, cromatina distribuída de maneira irregular, figuras de mitose atípicas e moderada quantidade de citoplasma contendo granulações eosinofílicas esféricas. Essas características indicam a linhagem mielóide. Ultraestruturalmente evidenciaram-se células com núcleo oval, volumoso, eletrodenso, com predomínio de eucromatina e citoplasma com numerosos grânulos esféricos, eletrodensos e homogêneos, indicando mielócitos com diferenciação para eosinófilos. Constatou-se também a presença de partículas virais tipo-C no espaço intercelular dos túbulos renais, no interior de vesículas intracitoplasmáticas dos mielócitos imaturos presentes na medula óssea e ovário, e PCR positivo para ALV-J.

Use of single-enzyme amplified fragment length polymorphism for typing Pasteurella multocida subsp. multocida isolates from pigs.

Single-enzyme amplified fragment length polymorphism (SE-AFLP) analyses were used to differentiate 97 isolates of porcine Pasteurella multocida subsp. multocida. The strains, isolated from animals with pneumonia, rhinitis, and septicemia, were classified as capsular types A, D, and F. SE-AFLP showed a discriminatory index of 0.87 and identified 18 different profiles.

Virulence properties of Escherichia coli isolated from ostriches with respiratory disease.

Eight Escherichia coli isolates from ostriches with respiratory disease were investigated for the presence of genes encoding the following adhesins: type 1 pili (fim), pili associated with pyelonephritis (pap), S fimbriae (sfa), afimbrial adhesin (afaI), temperature regulated adhesin, curli (crl, csgA) and temperature-sensitive hemagglutinin (tsh). Genes for heat labile (LT) and heat stable (STa and STb) enterotoxins, Shiga toxins (stx1 and stx2), cytotoxic necrotizing factor 1 (cnf), alpha-haemolysin (hly) and aerobactin (aer) production were also investigated. Other characteristics investigated were the presence of hemagglutination activity, growth on an iron-deficient medium, aerobactin production, serum resistance, adherence to chicken tracheal cells, pathogenicity for day-old chicks, and serogroup. Serogrouping showed that four isolates belonged to serogroup O2, two to serogroup O78, one to serogroup O9, and one to serogroup O21. The virulence genes found were: fim in all eight isolates, csgA in seven, aer in six, and pap, crl and tsh in one isolate each. All isolates analyzed were positive for mannose-resistant hemagglutination, adhered in vitro to ciliated tracheal epithelium, grew on iron-deficient medium, and showed serum resistance. Pathogenicity tests on day-old chickens revealed one highly pathogenic isolate, three of low pathogenicity and four isolates with intermediate pathogenicity.

Eficácia de vacina inativada contra a doença de Aujeszky: infecçäo experimental de suínos / Efficacy of an inactivated Aujeszky's disease virus vaccine: experimental infection of pigs

Um, vacina experimental contra a doença de Aujeszky (DA), inativada e adsorvida em adjuvante oleoso, foi testada em relaçäo á induçäo de imunidade, grau de proteçäo clínica e capacidade de reduzir a infecçäo, após desafio pela via intranasal. Grupos de 6 suínos, com 45 dias de idade, foram vacinados com uma ou duas doses de vacina, pelas vias intramuscular ou subcutânea, sendo mantido um grupo-testemunha, sem vacinaçäo. Todos os suínos vacinados apresentaram títulos de anticorpos neutralizantes, detectáveis através da prova de soroneutralizaçäo, sendo estatisticamente superiores nos animais que receberam duas doses de vacina. A vacinaçäo preveniu as manifestaçöes clínicas da doença após desafio, principalmente nos animais que receberam duas doses de vacina quando comparado com os que receberam 1 dose. Em todos os animais, vacinados e näo-vacinados, foi possível a detecçäo do vírus da doença de Aujeszky (VDA) nas amígdalas, através da técnica de imunofluorescência direta. A porcentagem de amígdalas positivas nos suínos vacinados com duas doses foi inferior quando comparada àquela de suínos näo-vacinados, no 2º e 7º dias pós-infecçäo. Em suínos vacinados com duas doses de vacina, pela via subcutânea, a taxa de infecçäo foi estatisticamente menor que naqueles vacinados com uma dose, pelas vias intramuscular ou subcutênea, e näo-vacinadas

Endocardial fibroelastosis in a dog.

Endocardial fibroelastosis is an uncommon congenital heart disease in dogs that may be manifested by signs of left-sided congestive heart failure. A three-month-old, male, Fila Brasileiro dog developed signs of generalised heart failure. Physical examination revealed normal temperature, ascites, and pale and cyanotic mucous membranes. The pup died just after radiography which revealed ascites, hepatomegaly, severe cardiac enlargement and pulmonary oedema. At necropsy, serosanguineous fluid in the thorax and abdomen, pulmonary oedema, right ventricular dilatation, hypertrophy and dilatation of the left ventricle, and mitral valve incompetence were observed. The histopathological examination demonstrated that the thickening of the endocardium of the left atrium and left ventricle was due to the presence of elastic and collagen fibres, although there were no signs of an inflammatory process.

Studies on feeding of Argas (Persicargas) miniatus larvae (Acari: Argasidae) on naive chicks.

The histology of skin responses to infestation with Argas (Persicargas) miniatus Koch, 1844, larvae was investigated on previously unexposed 1-mo-old chicks. An amorphous, acidophilic substance, referred to as cement, was observed from 24 h after infestation until the ticks had detached. The morphology of the lesions changed gradually during the time of infestation. Initially, dissociation of collagen fibers and a mild infiltration with heterophil and mononuclear cells (12-24 h) was observed. Then, fibroblastic cords, mononuclear cell focuses, erythrocytes, and some heterophils (48-72 h) could be observed. Finally, predominance of fibroblast proliferation was noted.

Effect of different vehicles in carrageenan suspension on the rate of the inflammatory response of chicks

Este trabalho descreve o padräo de resposta de edema, aumento de permeabilidade vascular e exsudaçäo celular induzidos pela injeçäo de diferentes suspensöes de carragenina nos coxins plantares de 80 pintos machos, de três a quatro semanas de idade. As suspensöes de carragenina 0,5 por cento foram preparadas em: soluçäo de Ringer-Locke (RL), soluçäo aquosa de Glicose (G), água desmineralizada (W) ou tampäo fosfato salino (PBS). Antes, e às 0:15, 0:30, 1:00, 1:30, 2:00, 2:30, 3:00, 3:30 e 4:00 horas após a injúria, o volume da pata e a permeabilidade vascular foram avaliados através de pletismografia e extravasamento de Azul de Evans respectivamente. A exsudaçäo celular foi observada em cortes finos de tecido corado, 0:30, 1:30, 2:30 e 4:00 horas após a injeçäo de carragenina ou somente do veículo. A resposta inflamatória variou de acordo com a suspensäo de carragenina utilizada. A suspensäo C/PBS induziu uma resposta inflamatória menos intensa nos coxins plantares do que as suspensöes de C/W, C/G e C/RL

[Morphobiology and pathogenicity of Eimeria falciformis var. pragensis Cerna, Seraud, Mehlhorn & Scholtyseck, 1974 in mouse (Mus musculus)]. / Morfobiologia e patogenicidade da Eimeria falciformis var. pragensis Cerná, Sénaud, Mehlhorn & Scholtyseck, 1974 em camundongo (Mus musculus).

The life cycle of a species of murine Eimeria, isolated from a commercial source of mice is described using experimental infections. A pure strain was established starting from a single oocyst administered to Eimeria-free Swiss white mice. The prepatent period was 6 1/2 to 7 days, and the patent period lasted 6 to 10 days. Oocysts were subspherical or ovoid, with a smooth double-layered colourless membrane. Micropila was absent. The sporulated oocysts measured 15.7-25.1 x 14.1-22.0 microns (X780 = 21.3 x 16.9 microns). One to 4 polar granules were present. The oocyst residuum was absent. Sporocysts were ellipsoid, measured 11.5 x 6.3 microns (n = 780), with Stieda body and a compact subspherical sporocyst residuum. The sporozoites were elongated, 17.7 x 3.2 microns (n = 100), partially curled around each other. The endogenous stages were found only in the large intestine, with at least 4 generations of schizonts. Mature 1st generation schizonts, first seen 24 hr post-infection (HPI) measured 10.3 x 10.6 microns and had 8 to 25 merozoites 5.0-10.0 x 1.0-3.0 microns. Mature 2nd generation schizonts were first seen 48 HPI, measured 14.4 x 8.1 microns and had 8 to 20 merozoites 11.0-16.0 x 2.0-3.0 microns. Two forms of presumably 3rd generation schizonts appeared between 72 and 96 HPI: one measuring 13.9 x 8.5 microns, containing large merozoites (17.0-19.0 x 2.0-4.0 microns) and the other measuring 7.3 x 10.4 microns, where 6 to 10 merozoites (8.0-13.0 x 1.0-3.0 microns) were found. Fourth generation schizonts measuring 10.4 x 11.9 microns, with 26 a 48 or more merozoites (8.0-13.0 x 2.0-3.0 microns) were first seen at 132 HPI. Mature macro and microgamonts were first observed at 144 HPI. The sporulation of 72.0% of the oocysts in 2.0% (w/v) potassium dichromate at 23-24 degrees C occurred in 9 days. Usually the infected mice showed depression, anorexia, weight loss, diarrhea or dysentery, and dehydration. The clinical picture w as more pronounced at 6 to 10 days post-infection (DPI). Mortality was highest between the 8th and 13th DPI, with a peak at 9 DPI in groups which received 1.1 x 10(4) to 4.4 x 10(4) oocysts. Groups infected with 5.5 x 10(3), 8.8 x 10(4) or 1.76 x 10(5) oocysts showed different results. Epithelial destruction, edema, inflammation, necrotizing enteritis followed by glandular regeneration and realing were observed restricted to the large intestine. The isolated Eimeria was named E. falciformis var. pragensis based on its morphobiological characteristics.

Effect of interleukin-1 on gamete interaction and mouse embryo development.

Early stages of endometriosis have been shown to be associated with infertility. The pathophysiology of this relationship is unclear. To determine if interleukin-1 (IL-1), a peritoneal macrophage product, has any effect on gamete interaction and early embryo development, human recombinant IL-1 was added to the coincubation of gametes in the sperm penetration assay (SPA), human zona pellucida assay (ZPPA) and culture medium (Ham's F-10) used for processing semen samples with the layering method, with analysis of velocity and motility after 24 hours. IL-1 was also added to mouse embryos (two cells) cultured for 72 hours. The results showed that IL-1 caused impairment of SPA and ZPPA when compared to control medium, without significant alterations in sperm velocity and motility. Also, IL-1 demonstrated significant inhibition of mouse embryo development. These results help explain subfertility associated with early stages of endometriosis.

Detection of endotoxin in human in vitro fertilization by the zona-free mouse embryo assay.

Endotoxin has been found to be a contaminant in human in vitro fertilization (IVF), leading to low pregnancy rates, mostly through embryo fragmentation. We wished to determine if standard quality control assays (one-cell and two-cell mouse embryo culture) were able to detect the presence of endotoxin and how they compared with the zona-free mouse embryo assays. Endotoxin was detected by the zona-free mouse embryo assays but not by the one- or two-cell mouse embryo assays. When excessive embryo fragmentation is noticed in the human IVF system, the use of zona-free mouse embryo assays is recommended.

Chronically inflamed tissue activates plasma mediators of vascular permeability.

1. After inflammation was induced in the foot-pad of rats with nistatin or BCG, injection of "non-activated" homologous plasma at the inflamed site caused a significant increase in the vascular permeability of the lesions (Evans blue test), which was more intense in older lesions, increasing from 7.83 +/- 1.11 to 8.70 +/- 1.18 (nistatin, 4 and 21 days) and 7.30 +/- 0.66 to 7.54 +/- 0.80 (BCG, 4 and 21 days). 2. Steroidal (acetyltriamcinolone, 2 mg/kg) and non-steroidal (indomethacin, 25 mg/kg) [corrected] anti-inflammatory drugs markedly decreased this effect on 14-day old lesions induced by nistatin plus "non-activated" plasma (2.37 +/- 0.10 for acetyltriamcinolone treatment vs 8.15 +/- 1.22 for untreated animals; 3.34 +/- 0.41 for indomethacin treatment vs 8.15 +/- 1.22 for untreated animals) and BCG plus "non-activated" plasma (1.67 +/- 0.11 for acetyltriamcinolone treatment vs 10.27 +/- 0.52 for untreated animals; 5.87 +/- 0.35 for indomethacin treatment vs 9.14 +/- 0.23 for untreated animals). 3. These data suggest that an increase in exudation in chronic lesions might result in "reactivation" of the process as observed clinically, for example, in rheumatoid arthritis in man.

Chronically inflamed tissue activates plasma mediators of vascular permeability

After inflammation was induced in the foot-pad of rats with nistatin or BCG, injection of "non-activated" homologous plasma at the inflamed site caused a significant increase in the vascular permeability of the lesions (Evans blue test), which was more intense in older lesions, increasing from 7.83 + or - 1.11 to 8.70 + or - 1.18 (nistatin, 4 and 21 days) and 7.30 + or - 0.66 to 7.54 + or - 0.80 (BCG, 4 and 21 days). Steroidal (acetyltriamcinolone, 25 mg/kg) and non-steroidal (indomethacin, 2 mg/kg) anti-inflammatory drugs markedly decreased this effect on 14-day old lesions induced by nistatin plus "non-activated" plasma (2.37 + or - 0.10 for acetyltriamcinolone treatment vs 8.15 + or - 1.22 for untreated animals; 3.34 + or - 0.41 for indomethacin treatment vs 8.15 + or - 1.22 for untreated animals) and BCG plus "non-activated" plasma (1.67 + or - 0.11 for acetyltriamcinolne treatment vs 10.27 + or - 0.52 for untreated animals; 5.87 + or - 0.35 for indomethacin treatment vs 9.14 + or - 0.23 for untreated animals). These data suggest that an increase in exudation in chronic lesions might result in "reactivation" of the process as observed clinically, for example, in rheumatoid arthritis in man

Do connective tissue components induce plasma activation in vivo?

1. This paper describes the effect of homologous plasma in contact with connective tissue on vascular permeability, edema and cell migration. 2. The contact of "non-activated" plasma with connective tissue structures does not result in generation of mediators responsible for increase in vascular permeability or in edema. 3. "Activated" plasma is able to induce vascular permeability and edema when in contact with connective tissue components. 4. Injection of "non-activated" or "activated" plasma induced a mild inflammatory cell migration.

Hyperglycemia in stressed small premature neonates.

The metabolic responses to a constant glucose infusion were measured in 30 premature infants, 700 to 1,550 gm. The study included 18 stressed premature infants who needed assisted ventilation, and 12 control premature infants. Metabolic measurements were similar in both groups in the cord and preinfusion samples. In the first postinfusion sample, glucose, cortisol, and glycerol values were higher in stressed than in control premature infants. Hyperglycemia was seen in 13 of stressed and in only one of control premature infants. Stressed infants who became hyperglycemic in the first postinfusion sample were then compared to stressed euglycemic infants. Insulin levels were higher, glycerol levels similar, but cortisol levels lower in stressed hyperglycemic than in stressed euglycemic premature infants. The etiology of hyperglycemia in stressed premature infants cannot be attributed to hypoinsulinemia or to hypercortisolemia, and is not associated with increased glycerol levels. There was no difference in mortality between stressed hyperglycemia and stressed euglycemic infants; stress, rather than hyperglycemia, was related to mortality.