One-tube nested polymerase chain reaction for detection of Chlamydia trachomatis

Here we present a one-tube nested PCR test, which allows the detection of minimal quantities of Chlamydia trachomatis in human fluids. This assay includes the use of an internal control to avoid false negative results due to the presence of inhibitors. The results obtained show that this assay is robust enough to be used for clinical diagnosis.     

Environment and individual: a dialectic relationship.

The role of development in current neo-Darwinian evolutionary theory is still underestimated. Only a few experimental and theoretical efforts have been made to bridge the gap, among which the theories of genetic assimilation, stabilising selection and autopoiesis. The relationship between the organism and its environment is a focal point for understanding development. The organism itself determines which environmental features are relevant to it, what represents a stimulus that would trigger its behaviour, and continuously affects the environment through its activities, in a dialectic relationship. Such a relationship is unique and diachronic, changing with time and defining the individual. Development in the broad sense and behavioural plasticity refer to the individual unlike evolution, which refers to populations.     

Soluble TNF-like cytokine (TL1A) production by immune complexes stimulated monocytes in rheumatoid arthritis

TNF-like cytokine (TL1A) is a newly identified member of the TNF superfamily of ligands that is important for T cell costimulation and Th1 polarization. However, despite increasing information about its functions, very little is known about expression of TL1A in normal or pathological states. In this study, we report that mononuclear phagocytes appear to be a major source of TL1A in rheumatoid arthritis (RA), as revealed by their strong TL1A expression in either synovial fluids or synovial tissue of rheumatoid factor (RF)-seropositive RA patients, but not RF-/RA patients. Accordingly, in vitro experiments revealed that human monocytes express and release significant amounts of soluble TL1A when stimulated with insoluble immune complexes (IC), polyethylene glycol precipitates from the serum of RF+/RA patients, or with insoluble ICs purified from RA synovial fluids. Monocyte-derived soluble TL1A was biologically active as determined by its capacity to induce apoptosis of the human erythroleukemic cell line TF-1, as well as to cooperate with IL-12 and IL-18 in inducing the production of IFN-gamma by CD4(+) T cells. Because RA is a chronic inflammatory disease with autoimmune etiology, in which ICs, autoantibodies (including RF), and various cytokines contribute to its pathology, our data suggest that TL1A could be involved in its pathogenesis and contribute to the severity of RA disease that is typical of RF+/RA patients.     

Keynote papers on sandhopper orientation and navigation

This article analyses the relevant studies that have made sandhoppers a model subject for the study of orientation, and traces the development of the paradigm through innovative hypotheses and empirical evidence. Sandhoppers are able to maintain their direction without sensorial contact with the goal, which is their burrowing zone extended along the beach, but very narrow across it. They actively determine the direction of their movements, according to their internal state and the environmental features encountered. Each population shows an 'innate directional tendency' adapted to the shoreline of origin, and the inexpert laboratory-born young behave in a similar way to the adults. Genetic differences have been demonstrated between, as well as within natural populations. The question of the calibration of the sun compass to orientation on a particular shoreline implies a redundancy of mechanisms of orientation. Orientation mechanisms may involve environmental cues perceived through diverse sensory modalities, and range from simple orientation reflexes to sun compass navigational systems. These include scototaxis and geotaxis, and the response to the silhouette of the dune, in addition to sun and moon orientation, which is dependent on the time of the day and orientates daily migrations on the beach. Different modalities of orientation may operate singly, or in conjunction with each other, and their ecological significance may vary according to the habitat and lifestyle of the animals. Taken collectively, the orientation behaviour of the group appears to be a most accommodating phenotype, with considerable adaptive potential. The evidence from comparative studies of different populations promotes consideration of behavioural plasticity as an adaptation to changing coastlines.     

Efficient and low-cost alternative of lipase concentration aiming at the application in the treatment of waste cooking oils

Bioprocess and Biosystems Engineering - In this study, we evaluated the concentration of lipases from Aspergillus niger using efficient and low-cost methods aiming at application in the treatment...     

Locomotor activity rhythm of Talitrus saltator (Crustacea,Amphipoda) on a progradating sandy beach

In the Maremma Natural Park (Grosseto, Italy), the Collelungo beach exhibits a clear morphodynamics gradient, resulting in a severe erosion to a gradual accretion along the shoreline. Here, three sub-populations of the sandhopper Talitrus saltator (Montagu) (Crustacea, Amphipoda) were studied to highlight eventual intra- and inter-population variation of the endogenous locomotor rhythm. Individual activity recordings were carried out for 21 days in constant darkness and controlled temperature and humidity conditions. The variation of the free-running period was analysed at individual and sub-population levels, and the dependence on intrinsic (individual features) and extrinsic (habitat of origin and season) factors was analysed. A seasonal variation was highlighted, related to the seasonal spontaneous activity of the species. In summer and autumn, a significant correlation between the behavioural variation in the sub-populations (period and definition of the period) and beach physical parameters (slope and width) defined the dependence of the behavioural gradient on the environmental gradient. The observed relationship may represent an adaptation to the local coastline dynamics, suggesting the importance of a plastic behaviour as adaptive response to a variable environment.     

Deletion of Syk in neutrophils prevents immune complex arthritis

The K/BxN serum transfer model of arthritis is critically dependent on FcγR signaling events mediated by spleen tyrosine kinase (Syk). However, the specific cell types in which this signaling is required are not known. We report that deletion of Syk in neutrophils, achieved using syk(f/f) MRP8-cre(+) mice, blocks disease development in serum transfer arthritis. The syk(f/f) MRP8-cre(+) mice display absent joint disease and reduced deposition of pathogenic anti-glucose-6-phosphate isomerase Abs in the joint (with a reciprocal accumulation of these Abs in the peripheral circulation). Additionally, syk(f/f) MRP8-cre(+) mice manifest poor edema formation within 3 h after formation of cutaneous immune complexes (Arthus reaction). Together, this suggests that neutrophil-dependent recognition of immune complexes contributes significantly to changes in vascular permeability during the early phases of immune complex disease. Using mixed chimeric mice, containing both wild-type and syk(f/f) MRP8-cre(+) neutrophils, we find no impairment in recruitment of Syk-deficient neutrophils to the inflamed joint, but they fail to become primed, demonstrating lower cytokine production after removal from the joint. They also display an increased apoptotic rate compared with wild-type cells in the same joint. Mast cell-deficient c-kit(sh/sh) mice developed robust arthritis after serum transfer whereas c-kit(W/Wv) mice did not, suggesting that previous conclusions concerning the central role of mast cells in this model may need to be revised. Basophil-deficient mice also responded normally to K/BxN serum transfer. These results demonstrate that Syk-dependent signaling in neutrophils alone is critically required for arthritis development in the serum transfer model.     

Phenotypic plasticity in sun orientation of sandhoppers

Summary Littoral sandhoppers perform zonal orientation mainly by means of sun orientation, which in Mediterranean populations was shown to be inborn, associated with a genetically determined directional tendency adapted to the shoreline of each population. In case of changes of the shoreline the genetic heterogeneity of populations and learning ability may cooperate in providing adaptation both at the population and at the individual level. This hypothesis has been tested carrying on studies on the ontogenesis of the reactionnorm of this behavioural trait inTalitrus saltator (Montagu) (Crustacea: Amphipoda) of a Tyrrhenian population which from previous results shows a well adapted seaward orientation. Sun orientation was analysed away from the sea shore, both in laboratory-raised individuals of different ages and in individuals captured in the field, by repeated releases on dry flat sand or in a glass bowl. Results showed variability within and between individuals of directional tendency, which varies in the individual life depending on age and experience. Particularly, age seems to bring canalization as variability within individuals tends to decrease with age. In order to evaluate the role of experience, we trained individuals to direct themselves towards a direction different from that genetically determined. The majority of the individuals showed a learning ability in the training situation. The importance of phenotypic plasticity in the oriented behaviour of sandhoppers is discussed.Dedicated in gratitude to Prof. Dr. Drs. h.c. M. Lindauer     

Orientation of the sandhopperTalitrus saltator (Amphipoda,Talitridae) living on dynamic sandy shores

Summary The littoral sandhopperTalitrus saltator Montagu maintains its position along the beach mainly by means of an innate solar orientation. Different populations show different directional tendencies depending on the direction of the sealand axis. Experiments were designed which aimed to disentangle the innate and acquired components of the escape orientation. Therefore, the solar orientation of experienced adults living on shores subject to fluctuations of the shoreline and of their laboratory-born (inexperienced) offspring were compared. The innate sun compass orientation shown by the young is modified by learning during life under natural conditions, depending on the variability of the shore. Results showed: (1) an improvement in the solar orientation in individuals living on relatively constant shores; (2) a loss of precision in individuals living on highly dynamic shores; (3) a change to a new ecologically efficient escape direction in individuals living on a relatively stable lagoon shore.Abbreviation TED theoretical escape direction