Evaluation of structural and secretory glycoconjugates in normal human jejunum by means of lectin histochemistry

Summary The labelling pattern of eight lectins was studied in jejunal samples from ten normal subjects, in order to define the normal distribution of structural and secretory glycoconjugates in the small bowel.The following lectins were studied by means of a peroxidase technique on formalin-fixed samples: Arachis hypogaea, Ricinus communis, Canavalia ensiformis, Lens culinaris, Phaseolus vulgaris, Triticum vulgaris, Ulex europaeus, Dolichos biflorus. Phaseolus vulgaris reacted with goblet cell mucus throughout the villus-crypt axis.Conversely Ulex europaeus, Dolichos biflorus and Triticum vulgaris lectin labelling of globet cells appeared to be confined to the upper part of the villi. This finding suggests that during cell migration from crypt to villus tip, the continuing maturation of goblet cells is associated with the differentiation of secretory carbohydrates, which probably parallels the cell maturation cycle. Lectin histochemistry appears to be a reliable tool for the study of structural and secretory glycoconjugates in the jejunal mucosa, and might be of value in the study of diseases in which the cell-maturation cycle in the small bowel is altered.     

Genetic structure of the population of Sicily.

Genetic heterogeneity within Sicily was investigated on the basis of ACP1, ADA, ESD, GLO1, PGD, PGM1, PGM2, SODA, ABO, and MN gene frequencies, and compared to those of other regions of Italy for which these same loci have been examined. Correspondence analysis revealed no differences within the island, at least at the provincial level, but showed genetic differentiation among Italian regions, distinctly clustering northern, central, and southern populations, respectively. These data indicate a close relationship between Sicily and southern Italy. In addition, the contribution of Middle Eastern populations to the gene pool of Sicily was evident.     

Energy-dispersive X-ray fluorescence analysis applied to biomonitoring on alps

Biological Trace Element Research - The results of a research in progress at the Istituto di Fisica Generale Applicata—University of Milan—on natural and anthropogenic elements'...     

Occurrence of cholecalciferol in the calcinogenic plant Trisetum flavescens.

The grass Trisetum flavescens causes severe calcification of soft tissues upon ingestion by various species, which has been ascribed by others to a 1,25(OH)₂ vitamin D₃-like activity.By a special purification procedure involving high pressure liquid chromatography and continuous biological testing the active principle was purified. By means of $\text{GC}\text{MS}$ it was identified as cholecalciferol, being present in a concentration of about 0.1 ppm in the lyophylized plant dry matter. 1,25(OH)₂ vitamin D₃ or other metabolites of vitamin D₃ were not present. Since such low concentrations could hardly explain the calcinosis observed, a more active “bound form” of vitamin D₃ may be present in Trisetum flavescens.     

1914G variant of BCHE gene associated with enzyme activity,obesity and triglyceride levels

Polymorphisms of butyrylcholinesterase (BChE) have been reported to be associated to weight, BMI variance and hypertriglyceridemia in adults and adolescents. The aim of the present study was to investigate the association of −116A (SNP: G/A; rs1126680) and 1914G (SNP: A/G; rs3495) variants of BCHE gene with anthropometric and biochemical variables associated with obesity in population sample of 115 individuals, from Southern Brazil. Participants were grouped in two categories: obese (BMI ≥ 30) and non-obese (BMI < 30). The 1914G allele showed significantly higher frequency in the obese group, and carriers of 1914G allele showed lower mean BChE activity when compared to 1914A carriers (p = 0.006). Higher means of BMI (p = 0.02) and triglyceride (TG; p = 0.01) were found in 1914G carriers (BMI = 27.57kg/m²; TG = 150.8 mg/dL) when compared to 1914A homozygotes (BMI = 25.55 kg/m²; TG = 107.9 mg/dL). Carriers of the −116A allele showed lower mean BChE activity than usual homozygotes, and the −116A variant was found in cis with 1914G (p < 0.0001; D′ = 1). The region of BCHE gene that contains the 1914G mutation site is target of microRNAs (miRs) and the response of BChE to glucocorticoids is especially influenced by these miRs. Therefore, it is possible that the 1914G allele can be interfering in gluconeogenesis, hyperglycemia, lipolysis and body fat distribution. This lower activity may cause an imbalance in lipid metabolism, which may lead to an increased predisposition to obesity and to a lower ability to maintain metabolic homeostasis.     

Beyond Motor Scheme: A Supramodal Distributed Representation in the Action-Observation Network

The representation of actions within the action-observation network is thought to rely on a distributed functional organization. Furthermore, recent findings indicate that the action-observation network encodes not merely the observed motor act, but rather a representation that is independent from a specific sensory modality or sensory experience. In the present study, we wished to determine to what extent this distributed and ‘more abstract’ representation of action is truly supramodal, i.e. shares a common coding across sensory modalities. To this aim, a pattern recognition approach was employed to analyze neural responses in sighted and congenitally blind subjects during visual and/or auditory presentation of hand-made actions. Multivoxel pattern analyses-based classifiers discriminated action from non-action stimuli across sensory conditions (visual and auditory) and experimental groups (blind and sighted). Moreover, these classifiers labeled as ‘action’ the pattern of neural responses evoked during actual motor execution. Interestingly, discriminative information for the action/non action classification was located in a bilateral, but left-prevalent, network that strongly overlaps with brain regions known to form the action-observation network and the human mirror system. The ability to identify action features with a multivoxel pattern analyses-based classifier in both sighted and blind individuals and independently from the sensory modality conveying the stimuli clearly supports the hypothesis of a supramodal, distributed functional representation of actions, mainly within the action-observation network.     

Modeling Staphylococcus epidermidis-Induced Non-Unions: Subclinical and Clinical Evidence in Rats

S. epidermidis is one of the leading causes of orthopaedic infections associated with biofilm formation on implant devices. Open fractures are at risk of S. epidermidis transcutaneous contamination leading to higher non-union development compared to closed fractures. Although the role of infection in delaying fracture healing is well recognized, no in vivo models investigated the impact of subclinical low-grade infections on bone repair and non-union. We hypothesized that the non-union rate is directly related to the load of this commonly retrieved pathogen and that a low-grade contamination delays the fracture healing without clinically detectable infection. Rat femurs were osteotomized and stabilized with plates. Fractures were infected with a characterized clinical-derived methicillin-resistant S. epidermidis (10³, 10⁵, 10⁸ colony forming units) and compared to uninfected controls. After 56 days, bone healing and osteomyelitis were clinically assessed and further evaluated by micro-CT, microbiological and histological analyses. The biofilm formation was visualized by scanning electron microscopy. The control group showed no signs of infection and a complete bone healing. The 10³ group displayed variable response to infection with a 67% of altered bone healing and positive bacterial cultures, despite no clinical signs of infection present. The 10⁵ and 10⁸ groups showed severe signs of osteomyelitis and a non-union rate of 83–100%, respectively. The cortical bone reaction related to the periosteal elevation in the control group and the metal scattering detected by micro-CT represented limitations of this study. Our model showed that an intra-operative low-grade S. epidermidis contamination might prevent the bone healing, even in the absence of infectious signs. Our findings also pointed out a dose-dependent effect between the S. epidermidis inoculum and non-union rate. This pilot study identifies a relevant preclinical model to assess the role of subclinical infections in orthopaedic and trauma surgery and to test specifically designed diagnostic, prevention and therapeutic strategies.     

Salivary calculi microbiota: new insights into microbial networks and pathogens reservoir

Sialolithiasis represents the most common disorders of salivary glands in middle-aged patients. It has been hypothesized that the retrograde migration of bacteria from the oral cavity to gland ducts may facilitate the formation of stones. Thus, in the present study, a microbiome characterization of salivary calculi was performed to evaluate the abundance and the potential correlations between microorganisms constituting the salivary calculi microbiota. Our data supported the presence of a core microbiota of sialoliths constituted principally by Streptococcus spp., Fusobacterium spp. and Eikenella spp., along with the presence of important pathogens commonly involved in infective sialoadenitis.     

Defective dendritic cell migration and activation of adaptive immunity in PI3Kgamma-deficient mice

Gene-targeted mice were used to evaluate the role of the gamma isoform of phosphoinositide 3-kinase (PI3Kgamma) in dendritic cell (DC) migration and induction of specific T-cell-mediated immune responses. DC obtained from PI3Kgamma-/- mice showed a reduced ability to respond to chemokines in vitro and ex vivo and to travel to draining lymph nodes under inflammatory conditions. PI3Kgamma-/- mice had a selective defect in the number of skin Langerhans cells and in lymph node CD8alpha- DC. Furthermore, PI3Kgamma-/- mice showed a defective capacity to mount contact hypersensitivity and delayed-type hypersensitivity reactions. This defect was directly related to the reduced ability of antigen-loaded DC to migrate from the periphery to draining lymph nodes. Thus, PI3Kgamma plays a nonredundant role in DC trafficking and in the activation of specific immunity. Therefore, PI3Kgamma may be considered a new target to control exaggerated immune reactions.