Host Kinase Activity is Required for Coxiella burnetii Parasitophorous Vacuole Formation

Coxiella burnetii is the etiologic agent of human Q fever and targets alveolar phagocytic cells in vivo wherein the pathogen generates a phagolysosome-like parasitophorous vacuole (PV) for replication. C. burnetii displays a prolonged growth cycle, making PV maintenance critical for bacterial survival. Previous studies showed that C. burnetii mediates activation of eukaryotic kinases to inhibit cell death, indicating the importance of host signaling during infection. In the current study, we examined the role of eukaryotic kinase signaling in PV establishment. A panel of 113 inhibitors was analyzed for their impact on C. burnetii infection of human THP-1 macrophage-like cells and HeLa cells. Inhibition of 11 kinases or two phosphatases altered PV formation and prevented pathogen growth, with most inhibitor-treated cells harboring organisms in tight-fitting phagosomes, indicating kinase/phosphatase activation is required for PV maturation. Five inhibitors targeted protein kinase C (PKC), suggesting a critical role for this protein during intracellular growth. The PKC-specific substrate MARCKS was phosphorylated at 24 h post-infection and remained phosphorylated through 5 days post-infection, indicating prolonged regulation of the PKC pathway by C. burnetii. Infection also altered the activation status of p38, myosin light chain kinase, and cAMP-dependent protein kinase, suggesting C. burnetii subverts numerous phosphorylation cascades. These results underscore the importance of intracellular host signaling for C. burnetii PV biogenesis

Does controlling for epicurean eating or the tendency to supersize food portions change the relationship between mindful eating and grazing?

The study examines the potential for Epicurean eating to offer fresh perspectives on the predictive value of mindful eating. This research seeks to ascertain whether accounting for Epicurean eating (or its antithesis, supersizing), could influence the previously identified negative relationship between mindful eating and grazing habits. In a cross-sectional study, 419 participants completed questionnaires on epicurean eating, grazing, and mindful eating. The findings suggested mindful eating and epicurean eating were significantly associated with grazing, with both variables accounting for a significant amount of variance in grazing. Further analysis of the mindful eating subscales showed that eating without distraction, eating with awareness, and hunger and satiety cues accounted for this association with grazing when epicurean eating was included. Finally, whilst eating without distraction, eating with awareness, and hunger and satiety cues were associated with grazing, preference for supersizing did not account for a significant amount of variance in the relationship with grazing. The complex interplay between grazing and mindful eating becomes more apparent when considering the influence of epicurean eating. Exploring cross-cultural factors through additional research could provide valuable insights into the dynamics of epicurean eating and grazing. Simultaneously, incorporating alternative mindful eating scales may yield a more nuanced interpretation of mindful eating. Collectively, these avenues of inquiry warrant further investigation. Limitations and future directions are discussed

Isocitrate Dehydrogenase of Helicobacter pylori Potentially Induces Humoral Immune Response in Subjects with Peptic Ulcer Disease and Gastritis

Background. H. pylori causes gastritis and peptic ulcers and is a risk factor for the development of gastric carcinoma. Many of the proteins such as urease, porins, flagellins and toxins such as lipo-polysaccharides have been identified as potential virulence factors which induce proinflammatory reaction. We report immunogenic potentials of isocitrate dehydrogenase (ICD), an important house keeping protein of H. pylori. Methodology/Principal Findings. Amino acid sequences of H. pylori ICD were subjected to in silico analysis for regions with predictably high antigenic indexes. Also, computational modelling of the H. pylori ICD as juxtaposed to the E. coli ICD was carried out to determine levels of structure similarity and the availability of surface exposed motifs, if any. The icd gene was cloned, expressed and purified to a very high homogeneity. Humoral response directed against H. pylori ICD was detected through an enzyme linked immunosorbent assay (ELISA) in 82 human subjects comprising of 58 patients with H. pylori associated gastritis or ulcer disease and 24 asymptomatic healthy controls. The H. pylori ICD elicited potentially high humoral immune response and revealed high antibody titers in sera corresponding to endoscopically-confirmed gastritis and ulcer disease subjects. However, urea-breath-test negative healthy control samples and asymptomatic control samples did not reveal any detectable immune responses. The ELISA for proinflammatory cytokine IL-8 did not exhibit any significant proinflammatory activity of ICD. Conclusions/Significance. ICD of H. pylori is an immunogen which interacts with the host immune system subsequent to a possible autolytic-release and thereby significantly elicits humoral responses in individuals with invasive H. pylori infection. However, ICD could not significantly stimulate IL8 induction in a cultured macrophage cell line (THP1) and therefore, may not be a notable proinflammatory agent

Structural characterization, DNA binding study, antioxidant potential and antitumor activity of diorganotin(IV) complexes against human breast cancer cell line MDA-MB-231

Five new organotin(IV) complexes, Me2SnL (1), n-Bu2SnL (2), tert-Bu2SnL (3), Ph2SnL (4) and n-Oct2SnL (5), have been synthesized from the reaction of R2SnCl2 (R= Me, Bu, tert-Bu, Ph, Oct) with N'-(3-ethoxy-2-hydroxybenzylidene)formohydrazide (H2L). The structural elucidation of synthesized compounds was done by FT-IR, 1H-NMR, 13C-NMR spectroscopy and single-crystal X-ray analysis. Crystallographic data of complex (1) showed seven coordinated central tin atom with distorted pentagonal bipyramidal geometry. Where in solution the Sn atom of synthesized complexes exhibit five coordination, confirmed from 1H-NMR. The results from DNA interaction studies via UV-visible spectroscopy, viscosity, cyclic voltammetry, and differential pulse voltammetry (DPV) suggested an intercalative mode of interaction between the synthesized compounds and SS-DNA. Furthermore, the complexes interact more significantly than ligand. Electrochemical and thermodynamic parameters, including diffusion coefficient, ∆H, ∆G, and ∆S, were calculated using cyclic voltammetry data. The linear plot of peak current (I) vs. square root of the scan rate (υ1/2) indicated the electrochemical processes to be diffusion controlled. The DPPH free radical scavenging assay results showed that complex (4) is an active antioxidant. In-vitro cytotoxicity of the synthesized compounds was determined on human breast cancer cell line MDA-MB-231 using tetrazolium-based MTT assay, and complexes (2), (3) and (4) showed significant cytotoxic activity. The structure-activity relationships may be utilised to direct the optimization of the activity of agents from this class of compounds by comparing the specifics of the compound structures, their DNA binding, and toxicity

Comparative genomics of <it>Helicobacter pylori </it>isolates recovered from ulcer disease patients in England

<p>Abstract</p> <p>Background</p> <p>Genomic diversity of <it>H. pylori </it>from many different human populations is largely unknown. We compared genomes of 65 <it>H. pylori </it>strains from Nottingham, England. Molecular analysis was carried out to identify rearrangements within and outside the <it>cag</it>-pathogenicity-island (<it>cag </it>PAI) and DNA sequence divergence in candidate genes. Phylogenetic analysis was carried out based on various high-resolution genotyping techniques.</p> <p>Results</p> <p>Analyses of virulence genes (<it>cag</it>T, <it>cag</it>E, <it>cag</it>A, <it>vac</it>A, <it>ice</it>A, <it>oip</it>A and <it>bab</it>B) revealed that <it>H. pylori </it>strains from England are genetically distinct from strains obtained from other countries. The toxigenic <it>vac</it>A s1m1 genotype was found to be less common and the plasticity region cluster was found to be disrupted in all the isolates. English isolates showed a predominance of <it>ice</it>A1 alleles and a functional proinflammatory <it>oip</it>A gene. The English <it>H. pylori </it>gene pool revealed several Asian/oriental features. This included the predominance of <it>cag</it>A – <it>glr </it>(<it>cag</it>A right junction) motif types III and II (up to 42%), presence of <it>vac</it>A m1c alleles and phylogenetic affinity towards East Asian / Amerindian gene pools based on fluorescent amplified fragment length polymorphism (FAFLP) analysis and <it>glm</it>M sequence analysis.</p> <p>Conclusion</p> <p>Overall, our results demonstrated genetic affinities of <it>H. pylori </it>in England with both European and the Asian gene pools and some distinctive genetic features of virulence genes that may have evolved in this important European population.</p

The cag Pathogenicity Island of Helicobacter pylori Is Disrupted in the Majority of Patient Isolates from Different Human Populations

The cag pathogenicity island (cag-PAI) is one of the major virulence determinants of Helicobacter pylori. The chromosomal integrity of this island or the lack thereof is speculated to play an important role in the progress of the gastroduodenal pathology caused by H. pylori. We determined the integrity of the cag-PAI by using specific flanking and internally anchored PCR primers to know the biogeographical distribution of strains carrying fully integral cag-PAI with proinflammatory behavior in vivo. Genotypes based on eight selected loci were studied in 335 isolates obtained from eight different geographic regions. The cag-PAI appeared to be disrupted in the majority of patient isolates throughout the world. Conservation of cag-PAI was highest in Japanese isolates (57.1%). However, only 18.6% of the Peruvian and 12% of the Indian isolates carried an intact cag-PAI. The integrity of cag-PAI in European and African strains was minimal. All 10 strains from Costa Rica had rearrangements. Overall, a majority of the strains of East Asian ancestry were found to have intact cag-PAI compared to strains of other descent. We also found that the cagE and cagT genes were less often rearranged (18%) than the cagA gene (27%). We attempted to relate cag-PAI rearrangement patterns to disease outcome. Deletion frequencies of cagA, cagE, and cagT genes were higher in benign cases than in isolates from severe ulcers and gastric cancer. Conversely, the cagA promoter and the left end of the cag-PAI were frequently rearranged or deleted in isolates linked to severe pathology. Analysis of the cag-PAI genotypes with a different biogeoclimatic history will contribute to our understanding of the pathogen-host interaction in health and disease