Inactivation and injury of Escherichia coli O157:H7 and Staphylococcus aureus by pulsed electric fields

Two pathogenic microorganisms Escherichia coli O157:H7 and Staphylococcus aureus, suspended in peptone solution (0.1% w/v) were treated with 12, 14, 16 and 20 kV/cm electric field strengths with different pulse numbers up to 60 pulses. Pulsed electric field (PEF) treatment at 20 kV/cm with 60 pulses provided nearly 2 log reduction in viable cell counts of E. coli O157:H7 and S. aureus. S. aureus cells were slightly more resistant than E.coli O157:H7 cells. The results related to the effect of initial cell concentration of E. coli O157:H7 on the PEF inactivation showed that more inactivation was obtained by decreasing initial cell concentration. Any possible injury by PEF was also investigated after applying 20 kV/cm electric field to the microorganisms. As a result, it was determined that there was 35.92 to 43.36% injury in E. coli O157:H7 cells, and 17.26 to 30.86% injury in S. aureus cells depending on pulse number. The inactivation results were also described by a kinetic model.     

Flocculating performances of exopolysaccharides produced by a halophilic bacterial strain cultivated on agro-industrial waste

This study reports the first systematic investigation of the flocculation dynamics of exopolysaccharides (EPSs) produced by a halophilic bacterial strain grown on pretreated molasses as fermentation substrate. The potential use of these EPSs as an easily biodegradable, natural alternative for synthetic polyelectrolytes which are widely used and contain toxic and carcinogenic monomers was investigated. Flocculating activities of the EPS samples in synthetic water, synthetic sea water and natural sea water media which were used as model raw waters were monitored via the Photometric Dispersion Analyser (PDA 2000) instrument and removals were determined by measuring residual turbidities. One of the six EPS specimens, which formed the largest flocs thus performed highest turbidity removal, exhibited flocculation performance and particle removal efficiency comparable with commercial cationic, nonionic and anionic synthetic polyelectrolytes.     

Whole genome sequencing of Turkish genomes reveals functional private alleles and impact of genetic interactions with Europe,Asia and Africa

Background

Turkey is a crossroads of major population movements throughout history and has been a hotspot of cultural interactions. Several studies have investigated the complex population history of Turkey through a limited set of genetic markers. However, to date, there have been no studies to assess the genetic variation at the whole genome level using whole genome sequencing. Here, we present whole genome sequences of 16 Turkish individuals resequenced at high coverage (32 × -48×).

Results

We show that the genetic variation of the contemporary Turkish population clusters with South European populations, as expected, but also shows signatures of relatively recent contribution from ancestral East Asian populations. In addition, we document a significant enrichment of non-synonymous private alleles, consistent with recent observations in European populations. A number of variants associated with skin color and total cholesterol levels show frequency differentiation between the Turkish populations and European populations. Furthermore, we have analyzed the 17q21.31 inversion polymorphism region (MAPT locus) and found increased allele frequency of 31.25% for H1/H2 inversion polymorphism when compared to European populations that show about 25% of allele frequency.

Conclusion

This study provides the first map of common genetic variation from 16 western Asian individuals and thus helps fill an important geographical gap in analyzing natural human variation and human migration. Our data will help develop population-specific experimental designs for studies investigating disease associations and demographic history in Turkey.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-963) contains supplementary material, which is available to authorized users.     

The effectiveness of the peer-delivered Thinking Healthy PLUS (THPP+) Program for maternal depression and child socioemotional development in Pakistan: study protocol for a randomized controlled trial

BackgroundThe negative effects of perinatal depression on the mother and child start early and persist throughout the lifecourse (Lancet 369(9556):145–57, 2007; Am J Psychiatry 159(1):43-7, 2002; Arch Dis Child 77(2):99–101, 1997; J Pak Med Assoc 60(4):329; J Psychosoma Res 49(3):207–16, 2000; Clin Child Fam Psychol Rev 14(1):1–27, 2011). Given that 10–35 % of children worldwide are exposed to perinatal depression in their first year of life (Int Rev Psychiatry 8(1):37–54, 1996), mitigating this intergenerational risk is a global public health priority (Perspect Public Health 129(5):221–7, 2009; Trop Med Int Health 13(4):579–83, 2008; Br Med Bull 101(1):57–79, 2012). However, it is not clear whether intervention with depressed women can have long-term benefits for the mother and/or her child. We describe a study of the effectiveness of a peer-delivered depression intervention delivered through 36 postnatal months, the Thinking Healthy Program Peer-delivered PLUS (THPP+) for women and their children in rural Pakistan.Methods/designThe THPP+ study aims are: (1) to evaluate the effects of an extended 36-month perinatal depression intervention on maternal and index child outcomes using a cluster randomized controlled trial (c-RCT) and (2) to determine whether outcomes among index children of perinatally depressed women in the intervention arm converge with those of index children born to perinatally nondepressed women. The trial is designed to recruit 560 pregnant women who screened positive for perinatal depression (PHQ-9 score ≥10) from 40 village clusters, of which 20 receive the THPP+ intervention. An additional reference group consists of 560 perinatally nondepressed women from the same 40 clusters as the THPP+ trial. The women in the nondepressed group are not targeted to receive the THPP+ intervention; but, by recruiting pregnant women from both intervention and control clusters, we are able to evaluate any carryover effects of the THPP+ intervention on the women and their children. Perinatally depressed women in the THPP+ intervention arm receive bimonthly group-based sessions. Primary outcomes are 3-year maternal depression and 3-year child development indicators. Analyses are intention-to-treat and account for the clustered design.DiscussionThis trial, together with the reference group, has the potential to further our understanding of the early developmental lifecourse of children of both perinatally depressed and perinatally nondepressed women in rural Pakistan and to determine whether intervening with women’s depression in the perinatal period can mitigate the negative effects of maternal depression on 36-month child development.

Trial registration

THPP-P ClinicalTrials.gov Identifier: {"type":"clinical-trial","attrs":{"text":"NCT02111915","term_id":"NCT02111915"}}NCT02111915 (registered on 9 April 2014).THPP+ ClinicalTrials.gov Identifier: {"type":"clinical-trial","attrs":{"text":"NCT02658994","term_id":"NCT02658994"}}NCT02658994 (registered on 21 January 2016).Sponsor: Human Development Research Foundation (HDRF).

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1530-y) contains supplementary material, which is available to authorized users.     

Micromorphological traits and essential oil of Micromeria longipedunculata Bräuchler (Lamiaceae)

Micromeria longipedunculata Bräuchler (syn. M. parviflora (Vis.) Rchb.) is an endemic Illyric-Balkan plant species from Bosnia and Herzegovina, Montenegro, and Albania. We investigated types and distribution of trichomes, pollen morphology, and chemical composition of essential oil (analysed by GC and GC-MS) in M. longipedunculata. Non-glandular trichomes, peltate trichomes, and two types of capitate trichomes (type 1 composed of one basal epidermal cell, and one head cell with subcuticular space; type 2 composed of one basal epidermal cell, two or three stalk cells, and one head cell with subcuticular space) were observed on leaves, bracteoles, the calyx, corolla, and the stem. The pollen grains had six apertures which were set in the equatorial pollen belt and showed medium reticulate ornamentation. A phytochemical analysis of essential oils from four different localities is characterized by similar chemical composition with spathulenol (23.7–39.5%), piperitone oxide (7.7–12.1%) and piperitone (7.3–8.9%) as the major compounds.     

Healing-promoting effect of bombesin treatment on chronic gastric ulcer in rats

To evaluate whether bombesin treatment has a facilitatory effect on the healing of chronic gastric ulcer, following the induction of ulcer by serosal application of acetic acid, rats were given bombesin (30 microg/kg/day; subcutaneously) or vehicle three times a day for 7, 14 or 21 days until they were decapitated. Neither food intake nor gastric emptying rate in either vehicle-treated or bombesin-treated groups was not statistically different from control rats. Similarly, ulcer indices and gastric myeloperoxidase (MPO) activities at the first and second weeks of injury were not different among the groups. However, in the 3-week ulcer group, bombesin treatment reduced tissue MPO level significantly back to control levels. Moreover, the analysis of the surface epithelium by scanning electron and light microscopy demonstrated a significant reduction in the severity of ulcers by bombesin treatment. Pretreatment with CCK antagonists (L-364,718 or L365,260; 25 micromol/kg/day) before bombesin treatment showed that neither of the CCK antagonists had a significant effect on the bombesin-mediated healing process, suggesting that CCK receptors are not involved in the action of bombesin. In accordance with the previous studies that show its acute gastroprotective effects, bombesin is also effective in promoting the healing process of chronic gastric ulcer in rats.     

Redox Biochemistry of Hydrogen Sulfide

H₂S, the most recently discovered gasotransmitter, might in fact be the evolutionary matriarch of this family, being both ancient and highly reduced. Disruption of γ-cystathionase in mice leads to cardiovascular dysfunction and marked hypertension, suggesting a key role for this enzyme in H₂S production in the vasculature. However, patients with inherited deficiency in γ-cystathionase apparently do not present vascular pathology. A mitochondrial pathway disposes sulfide and couples it to oxidative phosphorylation while also exposing cytochrome c oxidase to this metabolic poison. This report focuses on the biochemistry of H₂S biogenesis and clearance, on the molecular mechanisms of its action, and on its varied biological effects.