Immunologic memory response induced by a meningococcal serogroup C conjugate vaccine using the P64k recombinant protein as carrier

In this study, we used an adoptive lymphocyte transfer experiment to evaluate the ability of the P64k recombinant protein to recruit T-helper activity and induce immunologic memory response to the polysaccharide moiety in a meningococcal serogroup C conjugate vaccine. Adoptive transfer of splenocytes from mice immunized with the glycoconjugate conferred antipolysaccharide immunologic memory to naive recipient mice. The observed anamnestic immune response was characterized by more rapid kinetics, isotype switching from IgM to IgG and higher antipolysaccharide antibody titers compared with those reached in groups transferred with splenocytes from plain polysaccharide or phosphate-immunized mice. The memory response generated was also long lasting. Sera from mice transferred with cells from conjugate-immunized mice were the only protective in the infant rat passive protection assay, and also showed higher bactericidal titers. We demonstrated that priming the mice immune system with the glycoconjugate using the P64k protein as carrier induced a memory response to the polysaccharide, promoting a switch of the T-cell-independent response to a T-cell dependent one.     

Nocturnal masseter electromyographic activity of complete denture wearers

doi: 10.1111/j.1741‐2358.2011.00528.x Nocturnal masseter electromyographic activity of complete denture wearers Objective: Collection of normative data on activity patterns of the masseter during sleep in elderly denture wearers by portable electromyography (EMG) recorders. Background: Complete denture wearers might suffer from orofacial pain caused by myoarthropathies of the masticatory system. Indeed, denture instability may precipitate parafunctional habits and consequently muscle soreness and/or temporomandibular pain. Materials and methods: We collected normative masseter EMG data during sleep in 15 complete denture wearers (five women, 10 men, 56–88 years) by portable recorders in their natural environment. Activity periods (AP) were signal portions including subthreshold intervals ≤5 s. Signal amplitude was expressed in per cent of maximum voluntary contraction (%MVC). For this reason, maximum bite force was assessed. Twenty age‐matched dentate controls were also recorded for the maximum bite force. Results: We found 157.2 ± 86.5 AP per night, i.e. 24.0 ± 12.2 AP/h. Mean amplitude was 15.1 ± 4.3%MVC. AP lasted 6.8 ± 4.1 s, and their time integral was 126.3 ± 112.5%MVC?s. Maximum bite force was 116.8 ± 69.6 N in the edentulous, significantly lower than in controls (344.8 ± 150.4 N). Conclusions: Healthy complete denture wearers showed intermittent periods of nocturnal masseter activity of very low intensity and short duration.     

Arabinan Metabolism during Seed Development and Germination in Arabidopsis

Arabinans are found in the pectic network of many cell walls, where, along with galactan, they are present as side chains of Rhamnogalacturonan I. Whilst arabinans have been reported to be abundant polymers in the cell walls of seeds from a range of plant species, their proposed role as a storage reserve has not been thoroughly investigated. In the cell walls of Arabidopsis seeds, arabinose accounts for approximately 40% of the monosaccharide composition of non- cellulosic polysaccharides of embryos. Arabinose levels decline to -15% during seedling establishment, indicating that cell wall arabinans may be mobilized during germination. Immunolocalization of arabinan in embryos, seeds, and seedlings reveals that arabinans accumulate in developing and mature embryos, but disappear during germination and seedling establishment. Experiments using 14C-arabinose show that it is readily incorporated and metabolized in growing seedlings, indicating an active catabolic pathway for this sugar. We found that depleting arabinans in seeds using a fungal arabinanase causes delayed seedling growth, lending support to the hypothesis that these polymers may help fuel early seedling growth.     

Phenotypic integration of morphology and energetic performance under routine capacities: a study in the leaf-eared mouse Phyllotis darwini

A major goal of evolutionary physiology is to understand the intrinsic and the extrinsic factors that impose limitations on an animal’s energy budget. Although natural selection acts upon organismal traits such as performance (e.g., burst, sustained metabolic rates), from a mechanistic perspective, organismal performance results from the integrated functioning of different levels of biological organization. Hence, a better understanding of whole-animal performance must necessarily incorporate an explicit analysis of the integration between those different levels. Although this topic has been under intense scrutiny, overall there have been very few consistent patterns. Here, we explore the phenotypic integration between organ masses and the overall energy budget under routine capacities by statistically decomposing the covariance matrix (using path analysis and canonical correlation analysis) between organ masses and thermoregulatory burst and sustained metabolisms in cold acclimated individuals of Phyllotis darwini. Our results suggest that (a) central organs associated with the processing of food (cecum and liver), residuals (kidneys) and pumping of O₂ (heart) are tightly integrated to sustained expenditure and between themselves; (b) with the exception of the heart, central energy supplying organs are weakly related to burst expenditures; (c) sustained and burst metabolisms refer to complete different strategies and (d) basal metabolic rate is not related to any of the physiological or morphological traits considered in this study. Overall, our results support the hypothesis of an economic phenotype: animals maintain their excess capacities to face those critical extreme events, but their physiology and internal morphology are tightly integrated to function under routine needs.     

Incipient morphological castes in <Emphasis Type=Italic>Polistes gallicus</Emphasis> (Vespidae,Hymenoptera)

The occurrence of a pre-imaginal caste determination represents a sort of “point of no return” to eusociality. In some social insect taxa, including Polistes species, the occurrence of distinct queen and worker castes is still debated. Before this report, no clear morphological differences between reproductive and non-reproductive individuals were known. Here we show that several pre-imaginal morphological differences of the Van der Vecht organ occur between foundresses (queens) and workers. Geometric morphometrics revealed that queens are characterized by shape deformations of this organ, which is responsible for a typical allometric growth of the secretory area. This organ is predicted to be larger in foundresses compared to workers because its secretion is involved in defense against ants, in nestmate recognition and in preventing workers from challenging for direct reproduction. The results presented here indicate the existence of an incipient morphological caste determination Polistes gallicus and suggest that this species may have passed the “point of no return” for eusociality.     

In silico and in vivo analysis of ABI3 and VAL2 genes during somatic embryogenesis of Coffea arabica: competence acquisition and developmental marker genes

Plant Cell, Tissue and Organ Culture (PCTOC) - The employment of biotechnology-based approaches such as somatic embryogenesis has been applied to several plants including Coffea sp. Despite the...     

Detection of Helicobacter pylori in saliva and esophagus

The route of Helicobacter pylori transmission remains unclear and the currently suggested route is person-to-person transfer by faecal-oral and oral-oral mode. The aim of this study was to verify the presence of H. pylori in esophagus and saliva of humans. Saliva samples, mucosal biopsies from esophagus, gastric antrum and fundus were collected from 19 patients with positive Urea Breath Test (UBT). Gastric biopsies were used for H. pylori colture and antimicrobial susceptibility tests whereas saliva samples were collected to detect H. pylori with a Nested-PCR targeting 16S rRNA gene as well as esophagus biopsies which were also investigated with immunohistochemical staining. Helicobacter pylori was isolated in 18 patients both in gastric antrum and fundus. The molecular analysis, confirmed by comparative sequences evaluation, gave positive results in all saliva and esophageal samples whereas the immunohistochemistry revealed the presence of H. pylori in 15.8% (3/19) of the esophagus samples. Our data suggest that saliva and esophagus may be considered reservoirs for H. pylori in humans and emphasize the need to use more susceptible techniques for H. pylori detection, in particular in over-crowded sites. Identification of the transmission route of H. pylori is crucial in developing an effective plan of surveillance by finding new means of disease management.