Phloem‐specific resistance in Brassica oleracea against the whitefly Aleyrodes proletella

The cabbage whitefly [Aleyrodes proletella L. (Hemiptera: Aleyrodidae)] is becoming a serious pest in Brassica oleracea L. (Brassicaceae) crops. However, almost nothing is known about the interaction of this insect with its host plants. Previous studies have shown differences in the natural occurrence of adults, eggs, and nymphs on the closely related B. oleracea cultivars Christmas Drumhead and Riviera grown in the field. In this study, we aimed to identify the nature of these differences and to gain insight into the resistance mechanisms against A. proletella. We used no‐choice experiments on field‐ and greenhouse‐grown plants to show that the differences between the two cultivars are mainly based on antibiosis (traits that reduce herbivore performance) and not on antixenosis (traits that deter herbivory). This was further supported by laboratory choice experiments that indicated little or no discrimination between the two cultivars based on plant volatiles. We showed that resistance is dependent on plant age, that is, resistance increased during plant development, and is mainly independent of environmental factors. Analysis of probing behaviour revealed that the resistance trait affects A. proletella at the phloem level and that morphological differences between the two cultivars are most likely not involved. We suggest that compounds present in the phloem reduce sap ingestion by the whitefly and that this explains the observed resistance.     

The influence of differential processing of procathepsin H on its aminopeptidase activity, secretion and subcellular localization in human cell lines

Cathepsin H is a unique member of the cysteine cathepsins that acts primarily as an aminopeptidase. Like other cysteine cathepsins, it is synthesized as an inactive precursor and activated by proteolytic removal of its propeptide. Here we demonstrate that, in human cells, the processing of the propeptide is an autocatalytic, multistep process proceeding from an inactive 41kDa pro-form, through a 30kDa intermediate form, to the 28kDa mature form. Tyr87P and Gly90P were identified as the two major endopeptidase cleavage sites, converting the 30kDa form into the mature 28kDa form. The level of processing differs significantly in different human cell lines. In monocyte-derived macrophages U937 and prostate cancer cells PC-3, the 28kDa form is predominant, whereas in osteoblasts HOS the processing from the 30kDa form to the 28kDa form is significantly lower. The aminopeptidase activity of the enzyme and its subcellular localization are independent of the product, however the 30kDa form was not secreted in HOS cells. The activity of the resulting cathepsin H in U937 cells was significantly lower than that in HOS cells, presumably due to the high levels of endogenous cysteine protease inhibitor cystatin F present specifically in this cell line. These results provide an insight into the dependence of human cathepsin H processing and regulation on cell type.     

CNTNAP2 and Language Processing in Healthy Individuals as Measured with ERPs

The genetic FOXP2-CNTNAP2 pathway has been shown to be involved in the language capacity. We investigated whether a common variant of CNTNAP2 (rs7794745) is relevant for syntactic and semantic processing in the general population by using a visual sentence processing paradigm while recording ERPs in 49 healthy adults. While both AA homozygotes and T-carriers showed a standard N400 effect to semantic anomalies, the response to subject-verb agreement violations differed across genotype groups. T-carriers displayed an anterior negativity preceding the P600 effect, whereas for the AA group only a P600 effect was observed. These results provide another piece of evidence that the neuronal architecture of the human faculty of language is shaped differently by effects that are genetically determined.     

Using the Simulated Patient Methodology to Assess Paracetamol-Related Counselling for Headache

Objectives

Firstly, to assess paracetamol-related counselling. Secondly, to evaluate the patient’s approach as a determinant of counselling and to test the acceptability of the simulated patient method in Slovenian pharmacies.

Methods

The simulated patient methodology was used in 17 community pharmacies. Three scenarios related to self-medication for headaches were developed and used in all participating pharmacies. Two scenarios were direct product requests: scenario 1: a patient with an uncomplicated short-term headache; scenario 2: a patient with a severe, long-duration headache who takes paracetamol for too long and concurrently drinks alcohol. Scenario 3 was a symptom-based request: a patient asking for medicine for a headache. Pharmacy visits were audio recorded and scored according to predetermined criteria arranged in two categories: counselling content and manner of counselling. The acceptability of the methodology used was evaluated by surveying the participating pharmacists.

Results

The symptom-based request was scored significantly better (a mean 2.17 out of a possible 4 points) than the direct product requests (means of 1.64 and 0.67 out of a possible 4 points for scenario 1 and 2, respectively). The most common information provided was dosage and adverse effects. Only the symptom-based request stimulated spontaneous counselling. No statistically significant differences in the duration of the consultation between the scenarios were found. There were also no significant differences in the quality of counselling between the Masters of Pharmacy and Pharmacy Technicians. The acceptability of the SP method was not as high as in other countries.

Conclusion

The assessment of paracetamol-related counselling demonstrates room for practice improvement.     

RNA-containing cytoplasmic inclusion bodies in ciliated bronchial epithelium months to years after acute Kawasaki disease

Background

Kawasaki Disease (KD) is the most common cause of acquired heart disease in children in developed nations. The KD etiologic agent is unknown but likely to be a ubiquitous microbe that usually causes asymptomatic childhood infection, resulting in KD only in genetically susceptible individuals. KD synthetic antibodies made from prevalent IgA gene sequences in KD arterial tissue detect intracytoplasmic inclusion bodies (ICI) resembling viral ICI in acute KD but not control infant ciliated bronchial epithelium. The prevalence of ICI in late-stage KD fatalities and in older individuals with non-KD illness should be low, unless persistent infection is common.

Methods and Principal Findings

Lung tissue from late-stage KD fatalities and non-infant controls was examined by light microscopy for the presence of ICI. Nucleic acid stains and transmission electron microscopy (TEM) were performed on tissues that were strongly positive for ICI. ICI were present in ciliated bronchial epithelium in 6/7 (86%) late-stage KD fatalities and 7/27 (26%) controls ages 9–84 years (p = 0.01). Nucleic acid stains revealed RNA but not DNA within the ICI. ICI were also identified in lung macrophages in some KD cases. TEM of bronchial epithelium and macrophages from KD cases revealed finely granular homogeneous ICI.

Significance

These findings are consistent with a previously unidentified, ubiquitous RNA virus that forms ICI and can result in persistent infection in bronchial epithelium and macrophages as the etiologic agent of KD.     

Foetal Leydig cells and the neuroendocrine system

It has been shown that adult human Leydig cells express a number of neuroendocrine markers, and, therefore, could be considered as a part of the neuroendocrine system in the adult. A limited number of studies have dealt with the dynamics of development of human foetal Leydig cells, whereas studies on their neuroendocrine nature are still extremely rare. Therefore, the aim of our study was to investigate the development of human foetal Leydig cells in different weeks of gestation (wg) and to check if these cells express certain markers characteristic of the diffuse neuroendocrine system (DNS). Qualitative, quantitative histological studies and immunohistochemical analyses of human foetal testicular tissue have been performed. According to our data, Leydig cells formed a dynamic population of cells within the interstitum of testes in the period between 15 and 36 wg. The total number of Leydig cells of human foetal testes changed through different stages of gestation by means of 'pulsatile' dynamics (most likely, by following the variable level of gonadotropins). At early stages of development (15-17 wg) immunohistochemical reactions for the expression of neuron specific enolase (NSE) were positive within sex cords and between them, in the interstitum. Pro-spermatogonia in the sex cords were positive, as well as elongated spindle-shaped cells of the interstitum (very likely, precursors of Leydig cells). During the later stages of development (28-36 wg), excluding the pro-spermatogonia, the interstitial Leydig cells were also positive. The results of the immunohistochemical analyses (the expression of NSE) confirmed the hypothesis that human foetal Leydig cells were of neuroendocrine nature.     

Joint Report of the First International Comparison Test on Swine Lymphocyte Alloantigens (SLA)

The first international comparison test on swine lymphocyte alloantigens (SLA) was held in Helsinki, Finland in July 1986. The results reported were based on a comparison of 157 alloantisera originating from six laboratories. The antisera were tested against a selected panel of 264 lymphocyte samples belonging to four laboratories. The most common breeds in Europe were chosen for this first comparison test (Landrace and Large White). Eighteen of the 31 previously known specificities were confirmed and a new nomenclature was established.     

Mediolateral patterning of somites: multiple axial signals, including Sonic hedgehog, regulate Nkx-3.1 expression

The axial structures, the notochord and the neural tube, play an essential role in the dorsoventral patterning of somites and in the differentiation of their many cell lineages. Here, we investigated the role of the axial structures in the mediolateral patterning of the somite by using a newly identified murine homeobox gene, Nkx-3.1, as a medial somitic marker in explant in vitro assays. Nkx-3.1 is dynamically expressed during somitogenesis only in the youngest, most newly-formed somites at the caudal end of the embryo. We found that the expression of Nkx-3.1 in pre-somitic tissue explants is induced by the notochord and maintained in newly-differentiated somites by the notochord and both ventral and dorsal parts of the neural tube. We showed that Sonic hedgehog (Shh) is one of the signaling molecules that can reproduce the effect of the axial structures by exposing explants to either COS cells transfected with a Shh expression construct or to recombinant SHH. Shh could induce and maintain Nkx-3.1 expression in pre-somitic mesoderm and young somites but not in more mature, differentiated ones. The effects of Shh on Nkx-3.1 expression were antagonized by a forskolin-induced increase in the activity of cyclic AMP-dependent protein kinase A. Additionally, we confirmed that the expression of the earliest expressed murine myogenic marker, myf 5, is also regulated by the axial strucutres but that Shh by itself is not capable of inducing or maintaining it. We suggest that the establishment of somitic medial and lateral compartments and the early events in myogenesis are governed by a combination of positive and inhibitory signals derived from the neighboring structures, as has previously been proposed for the dorsoventral patterning of somites.