ULTRASONOGRAPHIC ASSESSMENT OF METALLIC CLIP CAROTID ANASTOMOSIS IN SHEEP

The aim of this study was to use ultrasonography to assess an experimental carotid arteriotomy followed by end-to-end anastomosis in the lamb. Animals were subjected to an experimental surgical procedure consisting of a right carotid artery arteriotomy and subsequent end-to-end anastomosis with nonpenetrating metallic clips. Left side arteries were used as control. Duplex ultrasonography was performed postoperatively to assess the evolution of the experimental anastomosis. Measurements were made on the right carotid to assess blood flow, peak systolic velocity, and end diastolic velocity, as well as arterial diameter. Animals were periodically checked during the six-month postoperative period. Operated vessels appeared normal during follow up, with pulsatile movements and size similar to non operated carotid arteries. A hyperechoic band, perpendicular to the vessel main axis, was seen on the longitudinal image in operated arteries, but not in the control group. This band corresponded to the anastomosis area, where the clips were positioned. No image suggestive of thrombosis was observed in any operated artery, and blood flow was maintained through the experiment. Finally, a decrease of vessel lumen diameter was evidenced at the level of the anastomosis during the first 30 postoperative days, but it was not present after the 90th postsurgical day. Duplex ultrasonography is a useful imaging technique for the assessment of anatomical details, acoustical properties of the vascular lumen, and study of the intimal surface and vessel wall in growing arteries subjected to surgery. Metallic clips as suturing technique in arterial anastomosis allow for normal vascular growth, as shown by the evolution of flow velocity and vessel diameter.     

Effects of continuously infusing glucose or casein into the terminal ileum on biomarkers of metabolism,inflammation, and intestinal morphology in growing pigs

Study objectives were to determine the effects of continuously infusing glucose (GLC) or casein (CAS) into the terminal ileum on biomarkers of metabolism, inflammation, and intestinal morphology in growing pigs. Crossbred gilts (n = 19; 81 ± 3 kg body weight [BW]) previously fitted with T-cannulas at terminal ileum were used in the current experiment. Following 4 d of acclimation, pigs were enrolled in 2 experimental 4-d periods (P). During P1, pigs were housed in individual pens and fed ad libitum for collection of baseline parameters. At the beginning of P2, pigs were assigned to 1 of 3 infusion treatments: 1) control (CON; water; 3 liters/d; n = 7), 2) GLC (dextrose 50%; 500 g/d; n = 6;), or 3) CAS (casein sodium salt; 300 g/d; n = 6). Water, GLC, and CAS solutions were continuously infused at a rate of 125 mL/h for the entirety of P2. Animals were euthanized at the end of P2, and intestinal tissue was collected. During P2, average daily feed intake differed across treatments and was reduced in GLC compared with CON pigs (14%), while CAS pigs consumed an intermediate amount (P = 0.05). Average daily gain and final BW were similar across treatments. A treatment by time interaction was observed for blood urea nitrogen (BUN; P < 0.01), as it decreased in GLC (21%) while it gradually increased in CAS (76%) pigs relative to CON pigs. Mild hyperthermia occurred with both GLC and CAS infusions relative to CON (+0.3 and 0.2 °C, respectively; P < 0.01). Blood neutrophils increased in CAS relative to CON pigs (26%) but remained similar between CON and GLC treatments (P < 0.01). Blood monocytes decreased in GLC relative to CON pigs (24%) while CAS pigs had an intermediate value (P = 0.03). Circulating lipopolysaccharide binding protein tended to decrease in GLC (29%) relative to CON pigs but remained similar between CON and CAS pigs (P = 0.10). Plasma tumor necrosis factor-alpha was similar across treatments. Ileum villus height:crypt depth was increased in CAS compared with CON pigs (33%; P = 0.05) while GLC pigs had an intermediate value. Colon myeloperoxidase-stained area increased in CAS compared with CON pigs (45%; P = 0.03) but remained similar between GLC and CON pigs. In summary, continuously infusing GLC or CAS into the terminal ileum appeared to stimulate a mild immune response and differently altered BUN patterns but had little or no effects on blood inflammatory markers, intestinal morphology, or key production parameters.     

Serum protein response and renal failure in canine Babesia annae infection

Babesia annae piroplasms have recently been recognised as a cause of infection and disease among dogs in Europe. The pathogenesis and clinical implications of this emerging disease remain poorly understood. We conducted this study to describe the electrophoretic profiles associated with the infection and to determine if B. annae associated azotaemia is caused by renal failure. We examined by microscopy 2,979 canine blood samples submitted to a diagnostic laboratory in NW Spain between September 2001 and April 2002. Small ring-shaped piroplasms were detected in blood smears of 87 samples and the identity of 58 of these presumptive cases were confirmed by PCR. This group of 58 infected dogs and a reference group of 15 healthy non-infected dogs were our study population. For all the dogs, serum protein response to -albumin, alpha-1 globulin, alpha-2 globulin, beta globulin and gamma globulin- was measured by capillary electrophoresis. The response of infected and non-infected dogs was compared and within infected dogs, the response of those with azotaemia (19) was compared with that of non-azotaemic dogs (39). Infected dogs presented a significant elevation of total proteins and all the different globulin fractions, and significantly lower levels of albumin compared to non-infected dogs. Among infected dogs, those presenting azotaemia had significantly lower concentrations of total proteins, albumin, beta and gamma globulins, and significantly higher values of alpha-2 globulin. Specific gravity was below the threshold of 1,025 for all dogs with azotaemia for which a urine sample was available (7) suggesting that azotaemia, in these dogs was of renal origin. Azotaemic dogs had higher concentrations of cholesterol and triglycerides, probably as a result of a liver compensatory response to the loss of proteins. We conclude that serum protein response in B. annae infected dogs corresponds to the pattern of a haemolytic syndrome with intense inflammatory reaction and that the azotaemia associated to the infection is very likely of renal origin.     

Subirrigation vs drip-irrigation: Effects on yield and quality of soilless grown cherry tomato

Summary

This research was carried out with the aim of comparing drip-irrigation with the trough bench technique of growing a cherry tomato crop, in terms of i) pH and EC of the substrate, ii) production and quality of the fruits and iii) efficiency in the use of the water. In the latter system, pots of opaque plastic with different characteristics were also used: i) with six bottom holes for subirrigation and without risers on the bottom; ii) with four bottom holes and with 3 mm risers on the bottom; iii) with a furrow cross on the bottom and with eight holes and 3 mm risers. This last pot was also used for the drip-irrigation. With both the fertigation methods the EC of the substrate showed a similar pattern over time in the lower and middle layers (always below 3 dS m^–1), whereas in the upper layer of the substrate it increased during the growing cycle with higher values with subirrigation compared with drip-irrigation, reaching 7.7 and 3.4 dS m^–1, respectively. The pots without risers used for the subirrigation showed the highest variations and values of EC of the recirculating nutrient solution, and the pots with risers and four holes the lowest. Tomato yield was lower with subirrigation than with the traditional free drainage drip-irrigation technique, but the quality was higher (dry matter, total soluble solids, and titratable acidity). Furthermore, with subirrigation the most frequent size class of the fruits was that with a diameter between 25 and 35 mm (considered optimal for cherry tomato), while with the open cycle it was that greater than 35.mm. No significant differences emerged between the three pot types. The water efficiency of the system was greater with subirrigation than with drip-irrigation. To produce 1 kg of fruits, 41 l of nutrient solution were necessary with the subirrigation (closed system) and 59 l with the drip-irrigation (open system).     

Impacts of rainstorms on soil erosion and organic matter for different cover crop systems in the western coast agricultural region of Syria

More and more cultivated coastal territories of Syria are being affected by increasing land degradation processes, specifically, by soil erosion due to non‐sustainable soil management. The use of cover crops can be considered an ideal solution to reduce the negative impacts of extreme rainfall events on soil erosion. However, there is no enough information about the main cultivated areas of Syria due to the current conflicts and the very few types of research conducted there. Therefore, the main aim of this research was to assess soil erosion (soil loss and sediment concentration) and hydrological response (run‐off and infiltration) considering the impact of different types of cropping systems on soil organic matter. To achieve this goal, using erosion plots, five grouped natural rainfall events and soil samples were collected, and infiltration measurements were performed between November 2012 and April 2013 (rainy season) on three different cropping systems (wheat, vetch, bean and control) with different sloping gradients (8% and 20%) in Tartous governorate (W Syria). Our results showed a cumulative rainfall amount from 68.8 to 201 mm during the study period. The highest sediment yield was generated in the control and wheat plots, registering 0.468 and 0.368 kg m^?2, respectively, with an inclination of 8%. For an inclination of 20%, the control and wheat plots registered 1.145 and 0.967 kg m^?2, respectively. In comparison with the control plots, there was a decrease in the total eroded organic matter, which ranged from 0.0579 (control) to 0.0289 (bean) kg m^?2 year^?1 in the plots with 20% inclination, and from 0.0233 (control) to 0.0069 (bean) kg m^?2 year^?1 with 8% inclination. To sum up, bean and vetch play an effective role to mitigate soil erosion, delay run‐off and reduce sediment yield. The output of this research provides first insights into the impact of different land uses on soil loss. Also, it could help rural inhabitants and farmers to correctly manage their soils against soil erosion processes.     

Engineered in situ bioremediation of soil and groundwater polluted with weathered hydrocarbons

In this work, we present our experience in the engineered in situ biostimulation of a hydrocarbon-polluted subsoil of an old metal-working plant. The site had a long history of fuel, lubricant oil, and diesel spills and leakages that were initially treated by means of physico-chemical techniques. After one year of treatment, weathered hydrocarbons were firmly sorbed in the unsaturated zone, limiting the effectiveness of the physico-chemical methods being applied. Also, low nutrient and dissolved oxygen levels limited natural attenuation yields. Therefore, a bioremediation approach based on the injection of hydrogen peroxide, an oleophilic fertilizer, and a surfactant was applied. Total petroleum hydrocarbons and gas chromatography-mass spectrometry determinations were performed as a chemical means of monitoring the process. Microbial populations, including the presence of hydrocarbon-degrading bacteria, were simultaneously analyzed during the process, using enrichment techniques and confocal laser scanning microscopy observations with fluorescent indicators. Hydrocarbon-degrading bacteria were already present in the polluted subsoil prior to the implementation of this bioremediation technique and increased noticeably during the first 2 months of treatment. Hence, the suitability of the nutrient and oxygen amending approach was confirmed as further demonstrated by chemical determinations.     

Visualizing gene expression in time and space in the filamentous bacterium Streptomyces coelicolor

Streptomycetes are prokaryotic microorganisms that exhibit a complex, mycelial fungus-like cycle of morphological differentiation. Development involves at least two spatially separated types of cells: the branching hyphae of the substrate mycelium, which penetrate the stratum upon which the colony feeds, and the upwardly protruding hyphae of the aerial mycelium, which undergo metamorphosis into spores. The luciferase-encoding luxA and luxB operon of the luminescent marine bacterium Vibrio harveyi was used as a promoter probe to visualize gene expression in differentiating colonies of Streptomyces coelicolor. Promoters for developmental genes of several kinds gave distinctive temporal and spatial patterns of light emission.     

Biodegradation of biodiesel and toluene under nitrate-reducing conditions and the impact on bacterial community structure

Purpose

Biodiesel is a renewable fuel that can be mixed with toluene and be accidentally released into anoxic ecosystems and impact soil microbial communities. Therefore, the aim of the present work was to examine, under nitrate-reduction conditions, the biodegradation of toluene in the presence of two different types of biodiesel (sunflower and rapeseed), and their impact on the bacterial community structure.

Materials and methods

Sediment samples were spiked individually with toluene, biodiesel, and their blends in laboratory-designed microcosms. Sunflower oil biodiesel was produced in the laboratory, while rapeseed oil biodiesel was a commercial product. Degradation of biodiesels and blends was monitored by directly measuring the substrate or indirectly by determining nitrate removal during the course of the experiment. Denitrification rates were estimated with the acetylene inhibition technique. Denaturing gradient gel electrophoresis was used to assess impacts on the bacterial community structure exposed to biodiesels, blends, and toluene.

Results and discussion

The results of this study showed that toluene and biodiesel were completely degraded within 10 days. Biodiesel significantly affected the bacterial community structure at a similar magnitude, independently of its origin. Additionally, toluene impacted the bacterial community and denitrification process to a lower extent than biodiesel and a clear decrease in the relative bacterial richness and diversity was shown in samples with biodiesel and blends. To the best of our knowledge, this is one of the first reports describing degradation of biodiesel alone and blends under nitrate-reducing conditions, and also the effects of these compounds on the denitrification process. In addition, due to the recently discovered “oxygenic denitrification” process, the acetylene inhibition technique and nitrous oxide quantification may not be the most adequate tool to estimate denitrification rates. Further detailed studies are advised to understand whether the identified bacterial community shift impacts ecosystem functions.

Conclusions

Our results help to understand the biodegradation of toluene, biodiesel, and their blends in sediments under nitrate-reducing conditions and might be important in implementing bioremediation strategies in anoxic environments.