In-vitro diagnosis of single and poly microbial species targeted for diabetic foot infection using e-nose technology

Background

Effective management of patients with diabetic foot infection is a crucial concern. A delay in prescribing appropriate antimicrobial agent can lead to amputation or life threatening complications. Thus, this electronic nose (e-nose) technique will provide a diagnostic tool that will allow for rapid and accurate identification of a pathogen.

Results

This study investigates the performance of e-nose technique performing direct measurement of static headspace with algorithm and data interpretations which was validated by Headspace SPME-GC-MS, to determine the causative bacteria responsible for diabetic foot infection. The study was proposed to complement the wound swabbing method for bacterial culture and to serve as a rapid screening tool for bacteria species identification. The investigation focused on both single and poly microbial subjected to different agar media cultures. A multi-class technique was applied including statistical approaches such as Support Vector Machine (SVM), K Nearest Neighbor (KNN), Linear Discriminant Analysis (LDA) as well as neural networks called Probability Neural Network (PNN). Most of classifiers successfully identified poly and single microbial species with up to 90% accuracy.

Conclusions

The results obtained from this study showed that the e-nose was able to identify and differentiate between poly and single microbial species comparable to the conventional clinical technique. It also indicates that even though poly and single bacterial species in different agar solution emit different headspace volatiles, they can still be discriminated and identified using multivariate techniques.     

Hepatic Stellate Cells Express Thymosin Beta 4 in Chronically Damaged Liver

Although the various biological roles of thymosin β4 (Tβ4) have been studied widely, the effect of Tβ4 and Tβ4-expressing cells in the liver remains unclear. Therefore, we investigated the expression and function of Tβ4 in chronically damaged livers. CCl4 was injected into male mice to induce a model of chronic liver disease. Mice were sacrificed at 6 and 10 weeks after CCl4 treatment, and the livers were collected for biochemical analysis. The activated LX-2, human hepatic stellate cell (HSC) line, were transfected with Tβ4-specific siRNA and activation markers of HSCs were examined. Compared to HepG2, higher expression of Tβ4 in RNA and protein levels was detected in the activated LX-2. In addition, Tβ4 was up-regulated in human liver with advanced liver fibrosis. The expression of Tβ4 increased during mouse HSC activation. Tβ4 was also up-regulated and Tβ4-positive cells were co-localized with α-smooth muscle actin (α-SMA) in the livers of CCl4-treated mice, whereas such cells were rarely detected in the livers of corn-oil treated mice. The suppression of Tβ4 in LX-2 cells by siRNA induced the down-regulation of HSC activation-related genes, tgf-β, α-sma, collagen, and vimentin, and up-regulation of HSC inactivation markers, ppar-γ and gfap. Immunofluorescent staining detected rare co-expressing cells with Tβ4 and α-SMA in Tβ4 siRNA-transfected cells. In addition, cytoplasmic lipid droplets were observed in Tβ4 siRNA-treated cells. These results demonstrate that activated HSCs expressed Tβ4 in chronically damaged livers, and this endogenous expression of Tβ4 influenced HSC activation, indicating that Tβ4 might contribute to liver fibrosis by regulating HSC activation.     

The associations of morningness–eveningness with anger and impulsivity in the general population

The aim of this study was to investigate the relationships among morningness–eveningness, impulsivity and anger in the general population. A total of 1000 community-dwelling subjects (500 males) aged 20–77 years (mean± SD age: 39.6 ± 11.6 years) completed the morningness–eveningness questionnaire (MEQ), Barratt impulsiveness scale (BIS), Spielberger State–Trait Anger Expression Inventory (STAXI) and Center for Epidemiologic Studies Depression Scale. Moderation and mediation analyses were performed to determine whether the relationship between two variables depended on the third variable, referred to as a moderator, and whether the third variable, known as a mediator, was associated with the other two variables establishing causation. The MEQ scores exhibited significant negative associations with BIS (p < 0.001) and STAXI (p < 0.001) scores, and high scores on the BIS were associated with high scores on the STAXI (p < 0.001). Impulsivity, as measured by the BIS, played a role as a moderator (p < 0.001) in the relationship between MEQ and STAXI, and anger, as measured by the STAXI, acted as moderator (p = 0.030) in the association between MEQ and BIS. However, after controlling for the interaction of the BIS and MEQ, the MEQ scores did not significantly predict STAXI scores (p = 0.070). Additionally, the effect size of the mediating effect of the BIS scores on the relationship between the MEQ and STAXI (percent mediation: 53.2%) was larger than that of the STAXI scores on the association between the MEQ and BIS (percent mediation: 31.8%). The present results demonstrate that morningness–eveningness was closely related with both impulsivity and anger in the general population. Furthermore, these findings suggest that impulsivity may exercise a great influence on the association between morningness–eveningness and anger in two ways: as a moderator by modulating this relationship based on the level of impulsivity and as a mediator by acting as an intermediary factor.     

Potential for Controlling Cholera Using a Ring Vaccination Strategy: Re-analysis of Data from a Cluster-Randomized Clinical Trial

IntroductionVaccinating a buffer of individuals around a case (ring vaccination) has the potential to target those who are at highest risk of infection, reducing the number of doses needed to control a disease. We explored the potential vaccine effectiveness (VE) of oral cholera vaccines (OCVs) for such a strategy.ConclusionsThese findings suggest that high-level protection can be achieved if individuals living close to cholera cases are living in a high coverage ring. Since this was an observational study including participants who had received two doses of vaccine (or placebo) in the clinical trial, further studies are needed to determine whether a ring vaccination strategy, in which vaccine is given quickly to those living close to a case, is feasible and effective.

Trial registration

ClinicalTrials.gov {"type":"clinical-trial","attrs":{"text":"NCT00289224","term_id":"NCT00289224"}}NCT00289224     

Different culture conditions used for arresting the G0/G1 phase of the cell cycle in goldfish (Carassius auratus) caudal fin-derived fibroblasts

One of the most important factors determining the success of the development of cloned embryos is the cell cycle stage of the donor cells. We investigated the effects of serum starvation, culturing to confluence and roscovitine treatment on the cell cycle synchronization of goldfish caudal fin-derived fibroblasts by flow cytometric analysis. The results show that culturing the cells to confluence (85.5%) and roscovitine treatment (82.71%) yield a significantly higher percentage of cells arrested in the G0/G1 (P < 0.05) phase than serum starvation (62.85%). Different concentrations of roscovitine (5, 10, or 15 μM) induce cell cycle arrest at the G0/G1 phase.     

Synthesis and antiproliferative activity of pyrrolo[3,2-b]pyridine derivatives against melanoma

Synthesis of a new series of diarylureas and amides having pyrrolo[3,2-b]pyridine scaffold is described. Their in vitro antiproliferative activity against human melanoma cell line A375 and HS 27 human fibroblast cell line was tested and the effect of substituents on the pyrrolo[3,2-b]pyridine was investigated. The newly synthesized compounds, except meta-substituted derivatives (Ij–k and Iv–w), generally showed superior or similar activity against A375 to Sorafenib. Among all of these derivatives, compounds Ir and It having 5-benzylamide substituted 4′-amide moieties showed the most potent antiproliferative activity against A375.     

Synthesis and SAR of (piperazin-1-yl-phenyl)-arylsulfonamides: A novel series of atypical antipsychotic agents

(Piperazin-1-yl-phenyl)-arylsulfonamides were synthesized and identified to show high affinities for both 5-HT_2C and 5-HT₆ receptors. Among them, naphthalene-2-sulfonic acid isopropyl-[3-(4-methyl-piperazin-1-yl)-phenyl]-amide (6b) exhibits the highest affinity towards both 5-HT_2C (IC₅₀ = 4 nM) and 5-HT₆ receptors (IC₅₀ = 3 nM) with good selectivity over other serotonin (5-HT_1A, 5-HT_2A, and 5-HT₇) and dopamine (D₂–D₄) receptor subtypes. In 5-HT_2C and 5-HT₆ receptor functional assays, this compound showed considerable antagonistic activity for both receptors.     

Functional reconstitution of the human serotonin receptor 5-HT6 using synthetic transmembrane peptides

Seven transmembrane (7TM) synthetic peptides mimicking the α-helical TM domains of the human serotonin receptor subtype-6 (5-HT₆) were autonomously reconstituted in detergent micelle and liposome environments. The degree of assembly of the 7TM peptides was characterized by monitoring the fluorescence resonance energy transfer (FRET) between donor and acceptor probes labeled at the amino termini of the second and fourth TM-peptides, respectively. The FRET efficiency of these peptides significantly increased when the 7TM peptides were reconstituted in liposome compare to detergent micelles. Furthermore, the 7TM peptides reconstituted in liposomes selectively bound to free serotonin and serotonin-conjugated magnetic beads, yielding a dissociation constant of 0.84 μM. These results show that the seven individual TM domains of 5-HT₆ can spontaneously assemble into liposomes in a conformation that mimics a native structure, and further demonstrate that specific interactions between TM helices play a critical role in the folding and stabilizing of GPCRs. The autonomous assembly of 7TM-peptides can be applied to the screening of agonists for GPCRs that are difficult to manipulate.