Reversal of thymic stromal lymphopoietin-induced airway inflammation through inhibition of Th2 responses

Lung-specific thymic stromal lymphopoietin (TSLP) expression is sufficient for the development of an asthma-like chronic airway inflammatory disease. However, the nature of the downstream pathways that regulate disease development are not known. In this study, we used IL-4- and Stat6-deficient mice to establish the role of Th2-type responses downstream of TSLP. IL-4 deficiency greatly reduced, but did not eliminate, TSLP-induced airway hyperresponsiveness, airway inflammation, eosinophilia, and goblet cell metaplasia, while Stat6 deficiency eliminated these asthma-like symptoms. We further demonstrate, using the chronic model of TSLP-mediated airway inflammation, that blockade of both IL-4 and IL-13 responses, through administration of an anti-IL-4R alpha mAb, reversed asthma-like symptoms, when given to mice with established disease. Collectively these data provide insight into the pathways engaged in TSLP-driven airway inflammation and demonstrate that simultaneous blockade of IL-4 and IL-13 can reverse established airway disease, suggesting that this may be an effective approach for the therapy of Th2-mediated inflammatory respiratory disease.     

Evaluation of biologically mediated changes in oil sands naphthenic acid composition by Chlamydomonas reinhardtii using negative‐ion electrospray orbitrap mass spectrometry

Industrial activity associated with oil‐sands extraction in Canada's Athabasca region produces a variety of contaminants of concern, including naphthenic acid fraction components (NAFCs). NAFCs are a complex mixture of organic compounds that are poorly understood both in terms of their chemical composition and effects on the environment. NAFC toxicity in the unicellular green algae Chlamydomonas reinhardtii P.A.Dangeard was correlated with the presence of the algal cell wall. It was suggested that the toxicity of NAFCs in C. reinhardtii was due to surfactant effects. Surfactant‐cell wall interactions are specific and governed by the compound class and structure, and by the nature of the biological material. Here, we investigate the effects of wildtype (WT) C. reinhardtii and two cell‐wall mutants on specific classes of NAFCs when growing cultures were treated with a 100 mg · L^?1 solution of NAFCs. Changes in the NAFC composition in the media were examined using high resolution mass spectrometry over a period of 4 d. Algal mediated changes in the NAFCs were limited to specific classes of NAFCs. In particular, the removal of large, classical naphthenic acids, with a double bond equivalent of 8, was observed in WT C. reinhardtii cultures. The observed algal mediated changes in NAFC composition would have been masked by low resolution mass spectrometry and highlight the importance of this tool in examining bioremediation of complex mixtures of NAFCs.     

Nontuberculous mycobacterium M. avium infection predisposes aged mice to cardiac abnormalities and inflammation

Biological aging dynamically alters normal immune and cardiac function, favoring the production of pro‐inflammatory cytokines (IL‐1β, IL‐6, and TNF‐α) and increased instances of cardiac distress. Cardiac failure is the primary reason for hospitalization of the elderly (65+ years). The elderly are also increasingly susceptible to developing chronic bacterial infections due to aging associated immune abnormalities. Since bacterial infections compound the rates of cardiac failure in the elderly, and this phenomenon is not entirely understood, the interplay between the immune system and cardiovascular function in the elderly is of great interest. Using Mycobacterium avium, an opportunistic pathogen, we investigated the effect of mycobacteria on cardiac function in aged mice. Young (2–3 months) and old (18–20 months) C57BL/6 mice were intranasally infected with M. avium strain 104, and we compared the bacterial burden, immune status, cardiac electrical activity, pathology, and function of infected mice against uninfected age‐matched controls. Herein, we show that biological aging may predispose old mice infected with M. avium to mycobacterial dissemination into the heart tissue and this leads to cardiac dysfunction. M. avium infected old mice had significant dysrhythmia, cardiac hypertrophy, increased recruitment of CD45⁺ leukocytes, cardiac fibrosis, and increased expression of inflammatory genes in isolated heart tissue. This is the first study to report the effect of mycobacteria on cardiac function in an aged model. Our findings are critical to understanding how nontuberculous mycobacterium (NTM) and other mycobacterial infections contribute to cardiac dysfunction in the elderly population.     

High levels of synaptosomal Na(+)-Ca(2+) exchangers (NCX1, NCX2, NCX3) co-localized with amyloid-beta in human cerebral cortex affected by Alzheimer's disease

Synaptosomal expression of NCX1, NCX2, and NCX3, the three variants of the Na(+)-Ca(2+) exchanger (NCX), was investigated in Alzheimer's disease parietal cortex. Flow cytometry and immunoblotting techniques were used to analyze synaptosomes prepared from cryopreserved brain of cognitively normal aged controls and late stage Alzheimer's disease patients. Major findings that emerged from this study are: (1) NCX1 was the most abundant NCX isoform in nerve terminals of cognitively normal patients; (2) NCX2 and NCX3 protein levels were modulated in parietal cortex of late stage Alzheimer's disease: NCX2 positive terminals were increased in the Alzheimer's disease cohort while counts of NCX3 positive terminals were reduced; (3) NCX1, NCX2 and NCX3 isoforms co-localized with amyloid-beta in synaptic terminals and all three variants are up-regulated in nerve terminals containing amyloid-beta. Taken together, these data indicate that NCX isoforms are selectively regulated in pathological terminals, suggesting different roles of each NCX isoform in Alzheimer's disease terminals.     

Galvechelone lopezmartinezae gen. et sp. nov., a new cryptodiran turtle in the Lower Cretaceous of Europe

Abstract: The Spanish town of Galve (Teruel) is notable because of the abundance of Upper Jurassic and, especially, Lower Cretaceous vertebrates recorded there. Although most groups have been studied in detail, information on turtles is very limited even though the material is relatively abundant. So far, no turtle taxa have been identified at the generic level. The only Lower Cretaceous articulated specimen from Galve is analysed here. It is identified as a representative of Cryptodira, Galvechelone lopezmartinezae gen. et sp. nov. Galvechelone lopezmartinezae is determined as a taxon belonging to the node that groups the turtles traditionally assigned to ‘Macrobaenidae’ and ‘Sinemydidae’, and other taxa such as the members of Panchelonioidea. This node, very abundant in the Lower Cretaceous of Asia, and with a broad subsequent distribution, has recently been recognized in the Lower Cretaceous of Europe. The diversity of basal members of Eucryptodira in the European Late Jurassic (represented by Thalassemydidae, Plesiochelyidae and Eurysternidae) was high. Owing to a relative scarcity of well‐preserved early Cretaceous turtles from Europe, the knowledge of this group of reptiles is limited. The study of the new turtle from Galve, together with the recently described Hoyasemys jimenezi, and the recently completed review of the enigmatic Chitracephalus dumonii demonstrate that members of the cryptodiran node grouping ‘Macrobaenidae’, ‘Sinemydidae’ and Panchelonioidea were also very diverse in this period.     

γ-Heptalactone is an endogenously produced quorum-sensing molecule regulating growth and secondary metabolite production by Aspergillus nidulans

Microbes monitor their population density through a mechanism termed quorum sensing. It is believed that quorum-sensing molecules diffuse from the microbial cells and circulate in the surrounding environment as a function of cell density. When these molecules reach a threshold concentration, the gene expression of the entire population is altered in a coordinated manner. This work provides evidence that Aspergillus nidulans produces at least one small diffusible molecule during its growth cycle which accumulates at high cell density and alters the organism's behaviour. When added to low-density cell cultures, ethyl acetate extracts from stationary phase culture supernatants of A. nidulans resulted in the abolition of the lag phase, induced an earlier deceleration phase with 16.3?% decrease in the final cell dry weight and resulted in a 37.8?% increase in the expression of ipnA::lacZ reporter gene construct, which was used as a marker for penicillin production compared to non-treated controls. The bioactive molecule present in the stationary phase extract was purified to homogeneity and was identified by liquid chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy to be ??-heptalactone. This study provides the first evidence that A. nidulans produces ??-heptalactone at a high cell density and it can alter the organism's behaviour at a low cell density. ??-Heptalactone hence acts as a quorum-sensing molecule in the producing strain.     

Improving ability to identify malaria and correctly use chloroquine in children at household level in Nakonde District, Northern Province of Zambia

BACKGROUND: This study investigated causes of malaria and how cases were managed at household level, in order to improve the ability to identify malaria and ensure correct use of chloroquine. It was conducted in Nakonde District, Northern Province of Zambia, between 2000 and 2001. Nakonde district is in a hyperendemic malaria province, where Plasmodium falciparum is predominant. The district has a total population of 153, 548 people, the majority of whom are peasant farmers. The main aim of the post intervention survey was to establish the proportion of caretakers of children five years and below, who were able to identify simple and severe malaria and treat it correctly using chloroquine in the home. METHODS: A baseline survey was conducted in five wards divided into intervention and control.Intervention and control wards were compared. Village health motivators and vendors were identified and trained in three intervention wards, as a channel through which information on correct chloroquine dose could be transmitted. A total of 575 carers, who were 15 years old and above and had a child who had suffered from malaria 14 days before the survey commenced, were interviewed. The two control wards received no intervention. 345 caretakers were from the intervention wards, while 230 came from the control wards. Identification of malaria and correct use of anti-malarial drugs was assessed in terms of household diagnosis of malaria in children under five years, type and dose of anti-malarial drugs used, self medication and the source of these anti-malarials. RESULTS: The majority of respondents in the study were females (81%). Chloroquine was the most frequently used anti-malarial (48.5%) in both the intervention and control wards. There was no difference between the intervention and control wards at pre-intervention (P = 0.266 and P = 0.956), in the way mothers and other caretakers identified simple and severe malaria. At baseline, knowledge on correct chloroquine dosage in the under five children was comparable between intervention and control wards. Post-intervention revealed that mothers and other caretakers were 32% and 51%, respectively, more likely to identify simple and severe malaria. There was a 60% increase on correct chloroquine dosage in all age groups among carers living in post-intervention wards. CONCLUSION: Compliance with standard therapeutic doses and correct identification of malaria was poorest in control wards, where no motivators and vendors were trained.     

Combined prime-boost vaccination against tick-borne encephalitis (TBE) using a recombinant vaccinia virus and a bacterial plasmid both expressing TBE virus non-structural NS1 protein

Background  

Heterologous prime-boost immunization protocols using different gene expression systems have proven to be successful tools in protecting against various diseases in experimental animal models. The main reason for using this approach is to exploit the ability of expression cassettes to prime or boost the immune system in different ways during vaccination procedures. The purpose of the project was to study the ability of recombinant vaccinia virus (VV) and bacterial plasmid, both carrying the NS1 gene from tick-borne encephalitis (TBE) virus under the control of different promoters, to protect mice against lethal challenge using a heterologous prime-boost vaccination protocol.     

Cyclobutane analogs of GABA

Bothcis-andtrans-3-aminocyclobutane-1-carboxylic acid have been synthesized as conformationally restricted analogs of GABA. The cis isomer displayed weak to moderate GABA-like activity with respect to (1) inhibition of GABA uptake in rat brain minislices, (2) inhibition of sodium-independent binding of GABA to rat brain membranes, (3) activity as a substrate for GABA aminotransferase, and (4) depression of the firing rate of cat spinal neurons in vivo. The trans isomer was less effective on all four assays. The result has been interpreted in terms of the conformational pinning back of the polar groups by the cyclobutane ring in the trans GABA analog so that unfavorable steric interactions would occur between one of the methylene groups and a region of steric hindrance at the active sites for particular GABA processes.