Measurement of respiratory system compliance and respiratory system resistance in healthy dogs undergoing general anaesthesia for elective orthopaedic procedures

Objective The aim of this study was to investigate normal values for the dynamic compliance of the respiratory system (Crs) and respiratory system resistance (Rrs) in mechanically ventilated anaesthetized dogs.Study design Prospective clinical study.Animals Forty healthy dogs undergoing elective orthopaedic surgery. Body weight was (mean ± SD) 26.8 ± 10.7 kg (range: 1.9–45.0 kg), age 4.7 ± 2.9 years (range: 0.1–10.6 years).Methods Dogs were premedicated with acepromazine and methadone administered intramuscularly and anaesthesia induced with propofol intravenously. After endotracheal intubation the dog's lungs were connected to an appropriate breathing system depending on body weight and isoflurane in oxygen administered for maintenance of anaesthesia. The lungs were ventilated mechanically with variables set to maintain normocapnia (end‐tidal carbon dioxide concentration 4.7–6.0 kPa). Peak inspiratory pressure, Crs, Rrs, tidal volume, respiratory rate and positive end‐expiratory pressure were recorded at 5, 30, 60, 90 and 120 minutes after start of mechanical ventilation. Cardiovascular variables were recorded at time of collection of respiratory data.Results General additive modeling revealed the following relationships: Crs = [0.895 × body weight (kg)] + 8.845 and Rrs = [?0.0966 × body weight (kg)] + 6.965. Body weight and endotracheal tube diameter were associated with Crs (p <0.001 and p =0.002 respectively) and Rrs (p = 0.017 and p =0.002 respectively), body weight being linearly related to Crs and inversely to Rrs.Conclusion and clinical relevance Body weight was linearly related to Crs while Rrs has an inverse linear relationship with body weight in mechanically ventilated dogs. The derived values of Crs and Rrs may be used for monitoring of lung function and ventilation in healthy dogs under anaesthesia.     

Acid‐base and electrolyte balance following administration of three crystalloid solutions in dogs undergoing elective orthopaedic surgery

ObjectiveTo compare acid–base balance and incidence of hyperchloraemic metabolic acidosis following administration of three crystalloid solutions to dogs undergoing anaesthesia for orthopaedic surgery.Study designProspective, randomised, clinical study.AnimalsSixty dogs.MethodsDuring a non–standardised anaesthetic, 0.9% saline (S), Hartmann's solution (H) or a polyionic glucose–free maintenance solution (M) was administered IV at 10 mL kg^?1 hour^?1. Venous blood pH, PCO₂, PCV, total protein, urea, sodium, potassium and chloride concentrations were measured at induction of anaesthesia (T0) and after 2 hours of fluid therapy (T2). Base excess (BE), bicarbonate, corrected chloride concentration (corrCl), osmolality, change in plasma volume (PV) and strong ion gap (SIG) were calculated. Changes in variables within groups (1–sample Student's t–test/Wilcoxon signed rank test) and between groups (1–way anova/Kruskal–Wallis) were assessed. Data are presented as median (interquartile range). Significance was set at p < 0.05.ResultsNo significant differences existed between groups for pH, PCO₂, PCV, total protein, urea, potassium, corrCl, PV and SIG. Potassium significantly increased in all groups. Significant differences existed between groups S and M for BE, sodium, chloride, bicarbonate and osmolality, and between groups H and M for sodium and osmolality. Chloride concentration significantly changed from 116 (114–117) to 117 (116–119) mmol L^?1 in group S, 116 (115–118) to 115 (113–117) mmol L^?1 in group H and 116 (115–118) to 114 (113–118) mmol L^?1 in group M. In groups H and M, sodium and osmolality decreased, and BE and bicarbonate concentration increased significantly. Plasma volume increased by 28 (14–44)%, 25 (5–40)% and 24 (13–33)% in groups S, H and M, respectively.Conclusion and clinical relevanceHyperchloraemic metabolic acidosis did not develop after intraoperative 0.9% saline, Hartmann's solution or maintenance solution at 10 mL kg^?1 hour^?1 for 2 hours in dogs undergoing elective orthopaedic surgery. Bicarbonate and BE increased after Hartmann's and maintenance solutions. Increases in potassium concentration were unexplained.     

Thiamin (vitamin B1) and thiamin phosphate esters in five cereal grains during maturation

Non-phosphorylated thiamin (T), thiamin monophosphate (TMP), and thiamin diphosphate (TDP) were extracted from whole grains of wheat (Triticum aestivum, cv. Dekan), triticale (Triticosecale, cv. SW Talentro), rye (Secale cereale, cv. Agronom), oats (Avena sativa, cv. Dominik), and barley (Hordeum vulgare, cv. Merlot) at different growth stages (from inflorescence emergence to full ripeness of the grains) and determined with high-performance liquid chromatography and fluorescence detection. No thiamin triphosphate or adenosine thiamin triphosphate was found in these cereals. Total thiamin levels (the sum of T and its phosphate esters) determined on a dry matter (DM) basis were found to be quite similar in all grain samples throughout the analysis period, ranging from 5.59 (wheat) to 13.00 nmol/g DM (oats). In spikelets 3–5 days after flowering, the total thiamin content in all cereals was 40–75% T, 5–13% TMP, and 18–46% TDP. Generally, T increased and TDP decreased continuously with grain development, with maximum T (88–99%), and minimum TDP (2–10%) at ripeness. No TMP was detected in mature grains. The results indicate that variation in T, TMP, and TDP levels is probably due above all to the conversion of phosphorylated thiamin phosphate esters into less highly or non-phosphorylated forms.     

Adsorption of Sodium Dodecylbenzenesulphonate (SDBS) on Candida maltosa EH 15 Strain: Influence on Cell Surface Hydrophobicity and n-alkanes Biodegradation

Water, Air, & Soil Pollution - The effect of exogenously added sodium dodecylbenzenesulphonate (SDBS) surfactant on biodegradation of a mixture of straight-chain aliphatic hydrocarbons...     

Large scale risk-assessment of wind-farms on population viability of a globally endangered long-lived raptor

Wind-farms receive public and governmental support as an alternative energy source mitigating air pollution. However, they can have adverse effects on wildlife, particularly through collision with turbines. Research on wind-farm effects has focused on estimating mortality rates, behavioural changes or interspecific differences in vulnerability. Studies dealing with their effects on endangered or rare species populations are notably scarce. We tested the hypothesis that wind-farms increase extinction probability of long-lived species through increments in mortality rates. For this purpose, we evaluate potential consequences of wind-farms on the population dynamics of a globally endangered long-lived raptor in an area where the species maintains its greatest stronghold and wind-farms are rapidly increasing. Nearly one-third of all breeding territories of our model species are in wind-farm risk zones. Our intensive survey shows that wind-farms decrease survival rates of this species differently depending on individual breeding status. Consistent with population monitoring, population projections showed that all subpopulations and the meta-population are decreasing. However, population sizes and, therefore, time to extinction significantly decreased when wind-farm mortality was included in models. Our results represent a qualitative warning exercise showing how very low reductions in survival of territorial and non-territorial birds associated with wind-farms can strongly impact population viability of long-lived species. This highlights the need for examining long-term impacts of wind-farms rather than focusing on short-term mortality, as is often promoted by power companies and some wildlife agencies. Unlike other non-natural causes of mortality difficult to eradicate or control, wind-farm fatalities can be lowered by powering down or removing risky turbines and/or farms, and by placing them outside areas critical for endangered birds.     

Italian aquaculture and the diffusion of alien species: costs and benefits

The aim of this review is to clarify the relation between Italian aquaculture and the introduction on alien species in Italy. In Italy, the most common aquatic alien species are rainbow trout and Manila clam, and they represent main economic product of Italian aquaculture. Wels catfish and red clawed crayfish have been voluntarily or involuntarily introduced for aquaculture scope, and they are now the most invasive alien aquatic species. Other alien naturalized species, as some salmonid species, are important economic resources in north Italy for inland professional fishery and are considered worthwhile of conservation. Thus, aquaculture is directly or indirectly responsible of the introduction of several alien species in Italy, but its effect on alien species diffusion is peculiar, as few successfully farmed species have become rapidly common. Until now, conventional aquaculture has played main role in the diffusion of alien species in Italy, while ornamental aquaculture will be the main source of alien introductions in the future.     

Resistance mechanisms of wild tomato germplasm to infection of Oidium neolycopersici

Tomato powdery mildew (Oidium neolycopersici) is one of the most devastating diseases of cultivated tomatoes worldwide. Although the first epidemics were recorded more than 25 years ago many aspects of this host-pathogen interaction are still not well understood. Detailed morphological and molecular studies of the anamorphs confirmed that O. neolycopersici is phylogeneticaly close to Erysiphe aquilegiae var. ranunculi. Host range is rather broad, apart from Solanaceae hosts were found in the families Apocynaceae, Campanulaceae, Crassulaceae, Cistaceae, Cucurbitaceae, Linaceae, Malvaceae, Papaveraceae, Pedialiaceae, Scrophulariaceae, Valerianaceae a Violaceae. Non-host resistance within these families is not based on inhibition of formation of primary haustorium, however, on post-haustorial hypersensitive reponse and another type of non-hypersensitive resistance. Screening of wild Solanum species (previous Lycopersicon spp.) germplasm revealed valuable sources of resistance (S. habrochaites, S. pennellii, S. cheesmaniae, S. chilense, S. peruvianum). The main resistance mechanism was found to be a hypersensitive response (HR), in some cases followed by limited development of the pathogen. However, there is a broad variation in resistance response on the histological and cytological level. Interaction between many wild Solanum spp. and O. neolycopersici is race-specific, at least three races were differentiated. In some interspecific crosses (S. lycopersicum × S. habrochaites) adult plant resistance was observed. Biochemical studies focusing on production of reactive oxygen species (ROS) and peroxidase activity during infection of O. neolycopersici showed that production of ROS and activity of corresponding enzymes is related to activation of defence responses in genotypes of wild Solanum sect. Lycopersicon. The significance of nitric oxide (NO) in O. neolycopersici pathogenesis was supported by experiments with NO donors and scavengers. In moderately resistant genotype S. chmielewskii, treatment by heat stress caused slight deceleration of pathogen development, increased production of jasmonic acid (JA) and abscisic acid (ABA) and increased peroxidase activity in infected plants. The different degree of tomato resistance/susceptibility did not markedly change the rate and extent of photosynthetic response to O. neolycopersici; only minimal impairment of photosynthesis was found in both susceptible and moderately resistant genotypes during the first 9 days after inoculation. The accumulated evidence confirm a crucial role of localised increased production of ROS and reactive nitrogen species (RNS) in response to pathogen penetration into plant tissue and its involvement in the plant resistance responses including the initiation and progression of plant cell death in host wild Solanum species. Crucial points of further research are discussed.