Quenching analysis in poplar clones exposed to ozone

Effects of ozone (O(3)) on photo-inhibition of photosynthesis were investigated in two poplar clones (Populus deltoides Bartr. ex Marsh. x maximowiczii A. Henry clone Eridano, O(3)-sensitive, and P. x euramericana (Dode) Guinier clone I-214, O(3)-resistant) by using pulse amplitude modulation chlorophyll fluorescence. After a 15-day exposure to O(3) at 60 nl l(-1) for 5 h day(-1), the effective photosynthetic quantum yield of photosystem II (PSII), as indicated by the ratio of variable to maximum chlorophyll fluorescence, significantly declined in both young and mature leaves of the two clones. Compared with control samples, mature leaves of both clones showed differences in fluorescence quenching and quantum yield of PSII when exposed to ozone fumigation. We conclude that photo-inhibition is caused by transformation of active reaction centers to photochemically inactive centers that dissipate excitation energy into heat, thus causing non-photochemical fluorescence quenching. The changes observed in chlorophyll a fluorescence of O(3)-treated young leaves in both clones are consistent with O(3) having a negligible effect on photosynthetic performance, but inducing a premature decrease in chlorophyll a concentration. A possible role of O(3) pollution on chlorophyll fluorescence yield is discussed.     

Preventing species invasion: A role for integrative taxonomy?

Integrative taxonomy, a multi‐disciplinary approach adding modern techniques to traditional morphology‐based methods (e.g. molecular and morphological criteria), can play an important role in bioinvasion research to identify introduced taxa, discover pathways of introduction and inform authorities to control and prevent future introductions. The present study is the first on introduced populations of Callosciurus, Asiatic tree squirrels, known as potentially invasive species in Europe (Italy, Belgium and France). We combined molecular (mitochondrial DNA markers: CoxI, D‐loop) and morphometric analysis on skulls, comparing them to the widest morphological and molecular datasets ever assembled for Callosciurus. Squirrels collected in Italy and Belgium share the same haplotypes and skull characteristics, but are conspicuously different from the French population in Antibes. Genetic data revealed close similarity between French squirrels and Pallas's squirrels, Callosciurus erythraeus, from Taiwan, China. Italian and Belgian squirrels formed an independent taxonomic lineage in genetic analyses, whose taxonomic rank needs further investigation. The morphological and morphometric characteristics of these 2 populations are, however, similar to known specimens assigned to Callosciurus erythraeus. These results may indicate a common origin for the populations found in Belgium and Italy. In contrast, French specimens suggest an independent introduction event of squirrels originating from Asia.     

Ultrasonographic differentiation between portal venous and parenchymal gas may be important for the prognosis of canine and feline hepatic emphysema: 37 cases

The aim of this retrospective, cross‐sectional, study was to evaluate clinical findings and outcomes for different ultrasonographic patterns of hepatic emphysema in dogs and cats. Dogs and cats with an ultrasonographic diagnosis of hepatic emphysema and a known outcome, from January 2010 to January 2018, were enrolled. The following data were recorded from medical and ultrasonographic records: ultrasonographic patterns of hepatic emphysema (parenchymal, portal venous, biliary), clinical signs, laboratory findings, and outcomes (favorable, poor). A total of 33 dogs and four cats met the inclusion criteria. Among these, 23 cases were classified as hepatic portal venous gas, 10 as parenchymal emphysema, and four as biliary emphysema. Clinical diagnosis categories were as follows: infection/sepsis (9), gastro‐intestinal disease (9), iatrogenic (9), trauma (5), and liver neoplasia (5). An increase in serum liver enzymes was significantly associated with parenchymal emphysema (P = .03). Other clinical and laboratory findings were not associated with the type of hepatic emphysema. Hepatic portal venous gas was mostly transient in patients with ultrasonographic follow‐up. The overall mortality was 40.5%. A significant difference was found between mortality by portal venous gas (21.7%) and mortality by parenchymal emphysema (90%) (P = .003). In conclusion, the ultrasonographic differentiation of hepatic emphysema between hepatic portal venous gas and parenchymal emphysema may be important for the prognosis of hepatic emphysema. The presence of parenchymal emphysema may be a poor prognostic indicator, while hepatic portal venous gas may be more benign. However, ultrasound findings should be carefully evaluated in the context of clinical findings.     

Beyond microbial diversity for predicting soil functions: A mini review

Since the advent of sequencing technologies,the determination of microbial diversity to predict microbial functions,which are the major determinants of soil functions,has become a major topic of interest,as evidenced by the 900 publications dealing with soil metagenome published up to 2017.However,the detection of a gene in soil does not mean that the relative function is expressed,and the presence of a particular taxon does not mean that the relative functions determined in pure culture also occur in the studied soil.Another critical step is to link microbial community composition or function to the product analyzed to determine flux rates.Indeed,flux rates might not only be highly dynamic,but several metabolites can depend on different reactions,which makes the link to one process of interest difficult or even impossible.This review also discusses biases caused by sampling,storage of samples,DNA extraction and purification,sequencing(amplicon-vs.metagenome sequencing),and bioinformatic data analysis.Insights and the limits of predicting microbial interactions by network inference methods are critically discussed,and finally,future directions for a better understanding of soil functions by using measurements of microbial diversity are presented.     

Microbial dynamics in Mediterranean Moder humus

There is a growing interest in the links between humus forms and soil biota, and little is known about these links in Mediterranean ecosystems. Culture-independent techniques, such as DNA extraction followed by DGGE and enzyme activities, allowed us to compare microbial communities in two horizons of a forest soil in different seasonal conditions. Direct in situ lysis was applied for extraction of DNA from soil; intracellular DNA was separated from extracellular and used to represent the composition of microflora. The aims were to describe how biochemical and microbiological parameters correlate with topsoil properties in typical Mediterranean Moder humus. Changes in bacterial and fungal community composition were evident from DGGE profiles. Degrees of similarity and clustering correlation coefficients showed that the seasonal conditions may affect the composition and activity of bacterial and fungal communities in the OH horizon, while in the E horizon the two communities were hardly modified. In the same season, OH and E horizons showed a different composition of bacterial and fungal communities and different enzyme activities, suggesting similar behaviour of eubacteria and fungi relatively to all the variables analysed. Evidently, different organic carbon content in soil horizons influenced microflora composition and microbial activities involved in the P and N cycles.     

Quantitative determination of diuron in ground and surface water by time-resolved fluoroimmunoassay: seasonal variations of diuron, carbofuran, and paraquat in an agricultural area

The aim of this research is to develop an ultrasensitive time-resolved fluorescence immunoassay (TR-FIA) for herbicide diuron in water samples. This method appears to be a promising approach, instead of conventional analytical techniques, in the screening procedure of organic pollutants because it is simple, rapid, and specific, and it does not require sample preconcentration or cleanup. Lanthanide chelate used as label allows to achieve sensitivity even 10 times higher than most of the other techniques. It has been applied to monitoring diuron contamination in specimens collected along a year in an agricultural area. The water specimens were collected monthly from lake, well, and irrigation ditch in the agricultural area south of Milan. Assay was performed using diuron-specific polyclonal antibody raised in sheep; as fluorescent marker, we used rabbit antisheep IgG conjugated with a chelating molecule complexed with Eu3+. The compound 4-(3-(3,4-dichloro-phenyl)-1-methyl-ureido)-butyric acid (CPD) was synthesized and conjugated with bovine serum albumin (BSA) to prepare a solid phase. Sensitivity achieved was 20 ng L-1 below the European Community limits. Paraquat (PQ) and carbofuran (CF) presence in the same samples has been also evaluated in a similar way, using immunoassays with time-resolved revelation systems. Diuron concentration shows a peak coinciding with a peak of carbofuran during summer periods. The peak of diuron was 65 pg/mL in June and 180 pg/mL in September in ditch and lake water samples, respectively; carbofuran concentration was higher than diuron in all samples: a carbofuran peak was revealed in September and October resulting in 87 ng/mL. Herbicide paraquat was not detectable in any assayed sample.     

Pulmonary rhodococcosis in a cat

Feline Rhodococcus equi infection is rare, despite the bacteria is widespread in the environment. R equi infection is typically observed in equine species but the infection has also been reported in dogs, cats and other domestic animals. There are a few reports regarding pulmonary R equi infection in cats and the disease appears to be limited to the skin and the subcutaneous tissue. This report describes the pathological, microbiological and the virulence features associated with an acute necrosuppurative pneumonia in a cat. To the best of our knowledge, this is the first report of feline pulmonary R equi infection in Italy.     

ECHOGRAPHIC EXAMINATION OF THE STIFLE JOINT AFFECTED BY CRANIAL CRUCIATE LIGAMENT RUPTURE IN THE DOG

Ultrasound is a useful technique for the study of normal and pathologic stifle joints, in particular for soft tissue examination. The aim of this study was to evaluate sonography for examination of stifle joints affected by cranial cruciate ligament rupture. Forty-two medium to giant breed dogs were studied. Tibial compression radiography was performed. A 7.5 MHz transducer with an incorporated 2 cm thick standoff was employed. Sagittal and midsagittal images were collected. The stifle was positioned in maximum flexion during sonography. Sonographic findings were compared with pathologic findings at surgery. Ultrasound was useful in evaluating the presence of fibrous tissue within the joint due to repair processes. It was observed in 70% of stifles with radiographic evidence of chronic osteoarthritis. In 19.6% of the joints it was possible to identify the ruptured cranial cruciate ligament. Ultrasound was not an accurate test for cruciate rupture evaluation, but was specific for the soft tissue pathologic changes which were observed consequent to joint instability.