Selective quantification of free 3-nitrotyrosine in exhaled breath condensate in asthma using gas chromatography/tandem mass spectrometry.

Reactive nitrogen species can cause oxidative modifications of certain amino acid residues in proteins, notably the modification of tyrosine to 3-nitrotyrosine (3-NT), which is a potentially useful marker of oxidative stress. Since lung diseases are associated with airway inflammation and oxidative stress, quantification of 3-NT in exhaled breath condensate (EBC) may provide a non-invasive means for monitoring ongoing inflammatory processes. 3-NT-like immunoreactivity has previously been detected in EBC, but no definitive evidence for the presence of 3-NT in EBC is available. Here, a method based on gas chromatography/negative ion chemical ionization/tandem mass spectrometry was established for the quantification of free 3-NT in EBC. The detection limit was 0.56 pM (corresponding to 3.0 amol microl(-1) sample injected) and the method was found to give linear results (r2 > 0.999) in the concentration range of 0-5.0 nM. The coefficient of variation (CV) for within-day and between-day precision were 11 and 12%, respectively. No artifactual nitration was observed during sample processing. The method was applied to study subjects with asthma (n = 8), and healthy subjects (n = 10), but only a slight non-significant increase in 3-NT levels was found in the former group (median [interquartile ranges]; 99 [50-547] amol s(-1) vs. 75 [35-147] amol s(-1)). No correlation with exhaled nitric oxide (NO), pulmonary function or EBC levels of total protein was observed. The 3-NT levels were much lower compared to previously reported levels, based on immunochemical measurements. The method does not allow the simultaneous quantification of tyrosine in samples.     

Trauma, dreaming, and psychological distress among Kurdish children.

The authors examined (a) how traumatic events are associated with children's dream structure and content and (b) which dream characteristics might moderate the negative impact of traumatic events on mental health. Participants were 122 Kurdish children (9-17 years old, M = 13.02, SD = 1.66). Their dreams were collected during 1 week using a semistructured dream diary and scored according to the dream atmosphere, the role of the dreamer, bizarreness, narrative quality, fragmentation and resolution, and content such as themes of death, persecution and rejection, hostility, and anxiety. The results substantiated the hypothesis that children exposed to a high level of traumatic events would report dreams characterized by unpleasant atmosphere, fragmented flow, and low levels of bizarre narrative quality. Pleasant dreams containing complete narratives and happy endings moderated the negative impact of traumatic events on children's mental health. The authors argue that dreaming allows cognitive-emotional processing of traumatic events and may thus enhance child well-being in war conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The side-effects of pesticides used in integrated production of peaches in Brazil on the egg parasitoid Trichogramma cacoeciae Marchal (Hym., Trichogrammatidae)

Abstract: The side‐effects of six pesticides used on peaches in Brazil were tested on the hymenopteran egg parasitoid Trichogramma cacoeciae using four laboratory tests: (a) adult parasitoid exposure to fresh pesticide residue on glass plates (worse case); (b) direct spray of host eggs enclosing the parasitoid egg, larvae or pupae (less‐exposed life stages); (c) exposure of adults to pesticide residues on plant leaves at different intervals after application (persistence); (d) Dose–response pesticide exposures of adults on glass plates. Two dose rates were used: (1) The highest recommended field dosage (FD) and (2) the predicted initial environmental concentrations (PIEC). The results showed that the preparations greatly differed in their initial toxicity and persistence. The insecticide Valient^® (methoxyphenozide) and the fungicide Venturol^® (dodine) were considered harmless to T. cacoeciae adults as they fell into the class 1 category according to the guidelines of the International Organization for Biological Control (IOBC) when parasitoids were directly exposed to chemical residues. The insecticide/acaricide Assist^® (mineral oil) was slightly harmful at the rate of PIEC 0.4 (40% of FD) and moderately harmful at FD. Pesticides in the categories harmless and moderately harmful can be considered for use in integrated pest management (IPM). The fungicide/acaricide Kumulus DF^® (sulphur) and the insecticides Dipterex^® 500 (triclorfon) and Lebaycid^® 500 (fenthion) were harmful at both concentrations. In the persistence test, Assist^® was short lived and therefore may in special cases (i.e. reduced direct contact) be considered for use in IPM, but Kumulus^® DF, Dipterex^® 500 and Lebaycid^® 500 constantly reduced parasitism between 77 and 100% and were rated as persistent (more than 30 days). The direct spray of parasitized host eggs at intervals after parasitism showed that Assist^® and Kumulus^® DF were harmless to the parasitoid egg, larvae and pupae within the host eggs. Dipterex^® 500 was slightly harmful when sprayed one day after parasitism (parasitoid egg) and moderately harmful to the other two stages (larvae and pupae). Lebaycid^® 500 was harmful to the parasitoid egg and larvae and moderately harmful to the pupae. The dose–response test showed that Kumulus^® DF and Dipterex^® 500 were toxic to T. cacoeciae. Kumulus^® DF was harmful from 1 PIEC 0.4 to 0.125 PIEC 0.4 dosages and was slightly harmful with 0.0625 PIEC 0.4 dosage. Dipterex^® 500 was harmful to T. cacoeciae in all the dosages tested.     

Molecular characterization of exons 6, 8 and 9 of ABCB4 gene in children with Progressive Familial Intrahepatic Cholestasis type 3

Aim of work: To estimate the frequency of mutations involving exons 6, 8 and 9 of Adenosine triphosphate-binding cassette, subfamily B, member 4 (ABCB4) gene among children with progressive intrahepatic cholestasis with high γ-GT activity (PFIC3).

Subjects and methods: Cross sectional study was conducted on 30 children with PFIC3. Genotyping was performed by sequencing analysis of exons 6, 8 and exon 9 of ABCB4 gene.

Results: Heterozygous synonymous polymorphic variant was detected in exon 6 (rs 1202283) and in exon 8 (rs 2109505). No mutations in studied exons were detected.

Conclusion: Exons 6, 8 and 9 mutations of ABCB4 gene are not common among Egyptian children with PFIC3.     

The <Emphasis Type="Italic">Helicobacter pylori</Emphasis> cytotoxin CagA is essential for suppressing host heat shock protein expression

Bacterial infections typically elicit a strong Heat Shock Response (HSR) in host cells. However, the gastric pathogen Helicobacter pylori has the unique ability to repress this response, the mechanism of which has yet to be elucidated. This study sought to characterize the underlying mechanisms by which H. pylori down-modulates host HSP expression upon infection. Examination of isogenic mutant strains of H. pylori defective in components of the type IV secretion system (T4SS), identified the secretion substrate, CagA, to be essential for down-modulation of the HSPs HSPH1 (HSP105), HSPA1A (HSP72), and HSPD1 (HSP60) upon infection of the AGS gastric adenocarcinoma cell line. Ectopic expression of CagA by transient transfection was insufficient to repress HSP expression in AGS or HEK293T cells, suggesting that additional H. pylori factors are required for HSP repression. RT-qPCR analysis of HSP gene expression in AGS cells infected with wild-type H. pylori or isogenic cagA-deletion mutant found no significant change to account for reduced HSP levels. In summary, this study identified CagA to be an essential bacterial factor for H. pylori-mediated suppression of host HSP expression. The novel finding that HSPH1 is down-modulated by H. pylori further highlights the unique ability of H. pylori to repress the HSR within host cells. Elucidation of the mechanism by which H. pylori achieves HSP repression may prove to be beneficial in the identification of novel mechanisms to inhibit the HSR pathway and provide further insight into the interactions between H. pylori and the host gastric epithelium.     

Social Network and Vulnerability: A Clear Link in Bedouin Society (Egypt)

In the last 60 years, the livelihoods of agro-pastoral and pastoral families in the arid and semi-arid zones in North Africa and the Middle East have undergone major changes caused by significant incentives to adopt a sedentary lifestyle and the increasing intensity of drought events. Such changes have also been influenced by land reclamation projects accompanied by the construction of reservoirs and dikes in the dry lands as well as the extension of irrigation canals in the desert in the Coastal Zone of the Western Desert, Egypt. To understand the changes in the traditional social organization of this desert society, and how these social changes have affected families’ ability to adapt to external shocks such as the recent 15-year drought, we developed a typological approach to investigate the link between family livelihoods and social capital in Bedouin society. We showed a clear link between physical assets (mainly land and animals), the nature and intensity of social links within the traditional society, and level of education. The analysis revealed also some new wealth accumulation processes in link with the socio-political influence of urban zones and the increasing level of education in the zone.     

Characterization of protein quality control components via dual reporter-containing misfolded cytosolic model substrates

Protein misfolding and protein aggregation are causes of severe diseases as neurodegenerative disorders, diabetes and cancer. Therefore, the cell has to constantly monitor the folding status of its proteome. Chaperones and components of the ubiquitin-proteasome system are key players in the cellular protein quality control process. In order to characterize components of the protein quality control system in a well-established model eukaryote - the yeast Saccharomyces cerevisiae - we established new cytosolic model substrates based on firefly luciferase and β-isopropylmalate dehydrogenase (Leu2). The use of these two different enzymes arranged in tandem as reporters enabled us to analyse the folding status and the degradation propensity of these new model substrates in yeast cells mutated in components of the cellular protein quality control system. The Hsp70 chaperone system known to be essential in the cellular protein quality control was chosen as a model for showing the high value of the luciferase-based model substrates in the characterization of components of the cytosolic protein quality control system in yeast.     

Controlled release of injectable liposomal in situ gel loaded with recombinant human bone morphogenetic protein-2 for the repair of alveolar bone clefts in rabbits

Background and objective: The aim of the present study was to develop and examine a new non-invasive injectable graft for the repair of alveolar bone clefts using recombinant human bone morphogenetic protein-2 (rhBMP-2) encapsulated within injectable liposomal in situ gel (LIG).

Method: Different liposomal formulations loaded with rhBMP-2 were prepared, and the effects of the preparation methods and lipid content on the efficiency of rhBMP-2 encapsulation within the liposomes were studied. For the preparation of in situ gel, deacetylated gellan gum (DGG) was used, and the in vitro gelation characteristics of the gel were evaluated. In vivo pharmacokinetics and histology were also assessed. Critical size alveolar defects were surgically created in the maxillae of 30 New Zealand rabbits and treated with different injectable formulae, including rhBMP-2 liposomes and in situ gel (rhBMP-2-LIG).

Results: The results indicated that the prepared rhBMP-2-LIG prolonged the release and residence time of BMP-2 within rabbits for more than 7 days. Histomorphometric assessment showed 67% trabecular bone filling of the defects treated using this novel formula.

Conclusion: BMP-2-LIG is a promising delivery device for the repair of alveolar bone defects associated with cleft deformities.