Metastatic cancer of unknown primary in 21 dogs

The aim of this retrospective study was to describe clinical features, treatment and outcome of 21 dogs with metastatic cancer of unknown primary (MCUP), a biopsy‐proven malignancy being diagnosed at a metastatic stage, in which the anatomical origin of the primary tumour cannot be detected. All dogs underwent total‐body computed tomography. Signalment, type and duration of clinical signs, metastasis site, pathology results, treatment and outcome were recorded. Carcinoma was the most common diagnosis (57.1%), followed by sarcoma, melanoma and mast cell tumour. The median number of disease sites per dog was 2, with bones, lymph nodes, lungs and spleen being the most frequent metastatic locations. The median survival for all dogs was 30 days. Overall, a primary site was not identified in 20 (95.2%) dogs. MCUP encompasses a variety of different pathologic entities and harbours a poor prognosis.     

Smenamides A and B,Chlorinated Peptide/Polyketide Hybrids Containing a Dolapyrrolidinone Unit from the Caribbean Sponge Smenospongia aurea. Evaluation of Their Role as Leads in Antitumor Drug Research

An in-depth study of the secondary metabolites contained in the Caribbean sponge Smenospongia aurea led to the isolation of smenamide A (1) and B (2), hybrid peptide/polyketide compounds containing a dolapyrrolidinone unit. Their structures were elucidated using high-resolution ESI-MS/MS and homo- and heteronuclear 2D NMR experiments. Structures of smenamides suggested that they are products of the cyanobacterial metabolism, and 16S rRNA metagenomic analysis detected Synechococcus spongiarum as the only cyanobacterium present in S. aurea. Smenamides showed potent cytotoxic activity at nanomolar levels on lung cancer Calu-1 cells, which for compound 1 is exerted through a clear pro-apoptotic mechanism. This makes smenamides promising leads for antitumor drug design.     

Chalinulasterol, a chlorinated steroid disulfate from the Caribbean sponge Chalinula molitba. Evaluation of its role as PXR receptor modulator

Chalinulasterol (1) a new chlorinated sterol disulfate was isolated from the Caribbean sponge Chalinula molitba. Its structure was elucidated using mass spectrometry and NMR experiments. The possible role of chalinulasterol as modulator of the PXR nuclear receptor was investigated but, in spite of the close structural relationship with the PXR agonist solomonsterol A (2), it showed no activity. The structural requirements for the PXR nuclear receptor activity were discussed.     

Distribution and thermal stability of physically and chemically protected organic matter fractions in soils across different ecosystems

Accrual of carbon (C) and nitrogen (N) in soil is a significant and realizable management option to mitigate climate change; thus, a clear understanding of the mechanisms controlling the persistence of C and N in soil organic matter (SOM) across different ecosystems has never been more needed. Here, we investigated SOM distribution between physically and chemically stabilized fractions in soils from a variety of ecosystems (i.e., coniferous and broadleaved forest soils, grassland soils, technosols, and agricultural soils). Using elemental and thermal analyses, we examined changes in the quantity and quality of physically fractionated SOM pools characterized by different mechanisms of protection from decomposition. Independently of the ecosystem type, most of the organic C and total N were found in the mineral-associated SOM pool, known to be protected mainly by chemical mechanisms. Indexes of thermal stability and C/N ratio of this heavy SOM fraction were lower (especially in agricultural soils) compared to light SOM fractions found free or occluded in aggregates, and suggested a marked presence of inherently labile compounds. Our results confirm that the association of labile organic molecules with soil minerals is a major stabilization mechanism of SOM, and demonstrate that this is a generalizable finding occurring across different mineral soils and ecosystems.     

IMAGING DIAGNOSIS—ULTRASONOGRAPHIC APPEARANCE OF SKELETAL MUSCLE METASTASES IN A DOG WITH HEMANGIOSARCOMA

A 13‐year‐old spayed female German shepherd dog was presented for acute onset of lethargy, anorexia, and disseminated erythematous skin lesions. Thoracic radiographs and abdominal ultrasonographic findings were consistent with metastatic hemangiosarcoma. Multiple, ill‐defined, irregularly shaped hypoechoic nodules were also detected within the thoracic and abdominal wall. Hemangiosarcoma metastases to the skeletal muscle were confirmed based on histopathological examination. Multivisceral involvement was also confirmed by necropsy. Metastatic neoplasia should be considered as a differential diagnosis for dogs with ill‐defined, irregular, hypoechoic, intramuscular nodules.     

Evaluation of three immunoserological techniques in the detection of porcine trichinellosis

Three immunoserological tests (IST) used for the detection of porcine trichinellosis, immunofluorescence (IF), enzyme-inmunoanalysis (EIA), and Western blot (WB), were compared. Three groups of animals were analyzed: Group 1, animals naturally infected with parasite burdens (PB) of <1 muscle larvae (ML)/g (n = 18); Group 2, animals naturally infected with PB of ≥2 ML/g (n = 23); Group 3, animals raised and home-slaughtered on farms in Argentina (n = 59). Animals from Groups 1 and 2 were identified in outbreaks and were analyzed by individual artificial digestion (AD) of ≥30 g of muscle. Animals in Group 3 were subjected to AD of 5 g of muscle.The detection percentages in sera of swine with the lower PB were 100% for IF, 72% for EIA, and 50% for WB. Eighty-three percent of the animals were serologically positive by two or three techniques. In pigs with the higher PB, the detection percentage was similar for IF and EIA (100% vs. 91%, respectively), and was lower for the WB (61%). Ninety-six percent of the animals were serologically positive by two or three techniques. Group 3 animals had similar detection percentages for the three techniques (IF, 30%; EIA, 29%; WB, 42%). Twenty-five percent of the animals were serologically positive by two or three techniques. Two animals were positive by AD with PB of 0.33 and 2.4 ML/g, and were positive for IF and WB, or IF, EIA, and WB. Results indicate that the sensitivity of each technique depends on the PB, and always ranked in sensitivity as IF > EIA > WB. For the lower PB, the decrease in the sensitivity is more pronounced for the EIA. Although the WB has a low sensitivity, the detection of the specific bands for Trichinella spiralis makes it a useful confirmatory tool. Considering that more than 83% of the parasitologically positive animals had 2 or 3 positive serological results using the techniques tested here, for the diagnosis of porcine trichinellosis, pigs positive by two of these serological techniques must be regarded as truly infected pigs.     

Antiobesity and cardiovascular toxic effects of Citrus aurantium extracts in the rat: a preliminary report

The effects of repeated oral administration of 2.5–20 mg/kg of two Citrus aurantium fruit extracts standardized to different concentrations of synephrine (4 and 6%, respectively) on food intake, body weight gain, arterial blood pressure, electrocardiogram (ECG) and mortality have been investigated in the rat. C. aurantium administration significantly reduced food intake and body weight gain. However, mortality (not observed in controls) was present in all C. aurantium treated groups. Arterial blood pressure was not modified, but ECG alterations (ventricular arhythmias with enlargement of QRS complex) were evident in animals treated with both extracts. Our data indicate that, in the rat, antiobesity effects of C. aurantium are accompanied by toxic effects probably due to cardiovascular toxicity.     

Relationship between rimsulfuron degradation and microbial biomass content in a clay loam soil

 The present research was conducted to determine the relationship between the degradation of rimsulfuron and soil microbial biomass C in a laboratory-incubated clay loam soil (pH=8.1; organic matter=2.1%) under different conditions and at different initial dosages (field rate, 10 and 100 times the field rate). The half-life values varied between 0.4 and 103.4 days depending on temperature, soil moisture and initial dose. Evidence suggested that rimsulfuron could pose environmental risks in cold and dry climatic conditions. Significant decreases in microbial biomass C content in rimsulfuron-treated soil, compared to untreated soil, were observed initially, especially at higher temperatures and low moisture levels, but never exceeded 20.3% of that in control soil. The microbial biomass C content then returned to initial values at varying times depending on incubation conditions. The relationship between herbicide degradation and microbial biomass C content gave parabolic curves (P<0.005 in all cases) under all conditions tested. Generally, maximum biomass C decrease coincided with the decrease in the concentration of rimsulfuron to about 50% of the initial dose, except at 10  °C and 100×, when biomass began to recover as early as 65–70% of the initial dose. The final equations could be useful to deduce the decrease of soil microbial biomass in relation to herbicide concentration. From the degradation kinetics of the herbicide, the time required to reach this decrease can also be calculated. Received: 19 July 1999     

Lattice effects observed in chaotic dynamics of experimental populations

Animals and many plants are counted in discrete units. The collection of possible values (state space) of population numbers is thus a nonnegative integer lattice. Despite this fact, many mathematical population models assume a continuum of system states. The complex dynamics, such as chaos, often displayed by such continuous-state models have stimulated much ecological research; yet discrete-state models with bounded population size can display only cyclic behavior. Motivated by data from a population experiment, we compared the predictions of discrete-state and continuous-state population models. Neither the discrete- nor continuous-state models completely account for the data. Rather, the observed dynamics are explained by a stochastic blending of the chaotic dynamics predicted by the continuous-state model and the cyclic dynamics predicted by the discrete-state models. We suggest that such lattice effects could be an important component of natural population fluctuations.     

Degradation of isoproturon and bentazone in peat- and compost-based biomixtures

BACKGROUND: The composition and properties of a biomixture used in a biobed are decisive for pesticide sorption and degradation. This study was performed to investigate the capability of compost‐based substrates in mixtures with citrus peel and vine branch straw and peat‐based substrates in mixtures with soil and vine branch straw at different levels in order to degrade isoproturon and bentazone. RESULTS: Dissipation and mineralisation rates of both pesticides were determined, and metabolic activity was followed as respiration. Compost‐based substrates showed faster pesticide dissipation in the presence of lignocellulosic materials, as in garden compost and vine branch straw. The increasing content of vine branch straw in peat‐based substrates does not seem to affect dissipation of the parent compounds. Low mineralisation rate was observed in all treatments. CONCLUSION: Higher pesticide degradation was observed in the lignocellulosic substrates, probably because of the development of lignin‐degrading microorganisms which have shown to be robust and are able to degrade recalcitrant pesticides. Copyright © 2010 Society of Chemical Industry