Metabolomic biomarkers and novel dietary factors associated with gestational diabetes in China

Introduction

Gestational diabetes mellitus (GDM) is impaired glucose tolerance first recognised during pregnancy; its development is associated with many adverse outcomes. Mechanisms of GDM development are not fully elucidated and few studies have used Chinese participants.

Objectives

The aim of this study was to investigate the maternal metabolome associated with GDM in a Chinese population, and explore the relationship with maternal diet.

Methods

Ninety-three participants were recruited at 26–28 weeks’ gestation from Chongqing, China. Maternal urine, serum, and hair metabolomes were analysed using gas and liquid chromatography–mass spectrometry. Dietary intake was assessed using a 96-item food frequency questionnaire.

Results

Of the 1064 metabolites identified, 73 were significantly different between cases and controls (P?<?0.05), but only 2-aminobutyric acid had both a p- and q-value?<?0.05. A “snack-based-dietary-pattern” was associated with an increased likelihood of GDM (odds ratio 2·1; 95% confidence interval 1.1–3.9). The association remained significant after adjustment for calorie intake but not food volume.

Conclusion

This study provides a comprehensive characterization of the maternal metabolome. The snack-based dietary pattern associated with GDM suggests that timing and frequency of consumption are important factors in the relationship between maternal diet and GDM.

     

Degradation of carbazole,dibenzothiophene and polyaromatic hydrocarbons by recombinant <Emphasis Type="Italic">Rhodococcus</Emphasis> sp.

Objectives

With the view of designing a single biocatalyst for biorefining, carbazole dioxygenase was cloned from Pseudomonas sp. and expressed in Rhodococcus sp.

Results

The recombinant, IGTS8, degraded both carbazole and dibenzothiophene at 400 mg/l in 24 h. Maximum carbazole degradation was in 1:1 (v/v) hexadecane/aqueous phase. Anthracene, phenanthrene, pyrene, fluoranthene and fluorine were also degraded without affecting the aliphatic component.

Conclusions

Recombinant Rhodococcus sp. IGTS8 can function as a single biocatalyst for removing major contaminants of fossil fuels viz. dibenzothiophene, carbazole and polyaromatic compounds.

     

Does centrifugation matter? Centrifugal force and spinning time alter the plasma metabolome

Background

Centrifugation is an indispensable procedure for plasma sample preparation, but applied conditions can vary between labs.

Aim

Determine whether routinely used plasma centrifugation protocols (1500×g 10 min; 3000×g 5 min) influence non-targeted metabolomic analyses.

Methods

Nuclear magnetic resonance spectroscopy (NMR) and High Resolution Mass Spectrometry (HRMS) data were evaluated with sparse partial least squares discriminant analyses and compared with cell count measurements.

Results

Besides significant differences in platelet count, we identified substantial alterations in NMR and HRMS data related to the different centrifugation protocols.

Conclusion

Already minor differences in plasma centrifugation can significantly influence metabolomic patterns and potentially bias metabolomics studies.

     

Iridoid and phenylethanoid/phenylpropanoid metabolite profiles of <Emphasis Type="Italic">Scrophularia</Emphasis> and <Emphasis Type="Italic">Verbascum</Emphasis> species used medicinally in North America

Introduction

Botanicals containing iridoid and phenylethanoid/phenylpropanoid glycosides are used worldwide for the treatment of inflammatory musculoskeletal conditions that are primary causes of human years lived with disability, such as arthritis and lower back pain.

Objectives

We report the analysis of candidate anti-inflammatory metabolites of several endemic Scrophularia species and Verbascum thapsus used medicinally by peoples of North America.

Methods

Leaves, stems, and roots were analyzed by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) and partial least squares-discriminant analysis (PLS-DA) was performed in MetaboAnalyst 3.0 after processing the datasets in Progenesis QI.

Results

Comparison of the datasets revealed significant and differential accumulation of iridoid and phenylethanoid/phenylpropanoid glycosides in the tissues of the endemic Scrophularia species and Verbascum thapsus.

Conclusions

Our investigation identified several species of pharmacological interest as good sources for harpagoside and other important anti-inflammatory metabolites.

     

Improved production of carotenoid-free welan gum in a genetic-engineered <Emphasis Type="Italic">Alcaligenes</Emphasis> sp. ATCC31555

Objective

To improve the production of welan gum and obtain a carotenoid-free strain while reducing the fermentation and post-treatment costs.

Results

The vitreoscilla globin (vgb) gene combined with the β-galactosidase (lacZ) promoter was inserted into the phytoene synthase (crtB) gene region of the chromosome in Alcaligenes sp. ATCC31555. When the recombinant strain was grown in a 5 l fermentor, welan gum was produced at 24 ± 0.4 g l^?1 compared to 21 g ± 0.4 g l^?1 in the wild type. Furthermore, the carotenoid-free welan gum produced using Alcaligenes sp. ATCC31555 VHb strain was less expensive with improved properties.

Conclusions

Alcaligenes sp. ATCC31555 VHb strain was a better neutral welan-producing strain with a higher production than the wild-type strain.

     

Metabolic response of porcine colon explants to in vitro infection by <Emphasis Type="Italic">Brachyspira hyodysenteriae</Emphasis>: a leap into disease pathophysiology

Introduction

Swine dysentery caused by Brachyspira hyodysenteriae is a production limiting disease in pig farming. Currently antimicrobial therapy is the only treatment and control method available.

Objective

The aim of this study was to characterize the metabolic response of porcine colon explants to infection by B. hyodysenteriae.

Methods

Porcine colon explants exposed to B. hyodysenteriae were analyzed for histopathological, metabolic and pro-inflammatory gene expression changes.

Results

Significant epithelial necrosis, increased levels of l-citrulline and IL-1α were observed on explants infected with B. hyodysenteriae.

Conclusions

The spirochete induces necrosis in vitro likely through an inflammatory process mediated by IL-1α and NO.

     

Medical students and physical education students as CPR instructors: an appropriate solution to the CPR-instructor shortage in secondary schools?

Background

Integrating cardiopulmonary resuscitation (CPR) training in secondary schools will increase the number of potential CPR providers. However, currently too few certified instructors are available for this purpose. Training medical students and physical education student teachers to become CPR instructors could decrease this shortage.

Aim

Examine whether medical students and physical education student teachers can provide CPR training for secondary school pupils as well as (i.?e., non-inferior to) registered nurses.

Methods

A total of 144 secondary school pupils were randomly assigned to CPR training by a registered nurse (n = 12), a  medical student (n = 17) or a physical education student teacher (n = 15). CPR performance was assessed after training and after eight weeks in a simulated cardiac arrest scenario on a resuscitation manikin, using manikin software and video recordings.

Results

No significant differences were found between the groups on the overall Cardiff Test scores and the correctness of the CPR techniques during the post-training and retention test. All pupils showed sufficient CPR competence, even after eight weeks.

Conclusion

Training by medical students or physical education student teachers is non-inferior to training by a registered nurse, suggesting that school teachers, student teachers and medical students can be recruited for CPR training in secondary schools.

     

Expression of a high sweetness and heat-resistant mutant of sweet-tasting protein,monellin, in <Emphasis Type="Italic">Pichia pastoris</Emphasis> with a constitutive GAPDH promoter and modified <Emphasis Type="Italic">N</Emphasis>-terminus

Objectives

To improve the stability and sweetness of the sweet-tasting protein, monellin, by using site-directed mutagenesis and a Pichia pastoris expression system with a GAPDH constitutive promoter.

Results

Both wild-type and E2 N mutant of single-chain monellin gene were cloned into the PGAPZαA vector and expressed in Pichia pastoris. The majority of the secreted recombinant protein, at 0.15 g/l supernatant, was monellin. This was purified by Sephadex G50 chromatography. The sweetness threshold of wild-type and E2 N were 30 μg/ml and 20 μg/ml, respectively. Compared with the proteins expressed in Escherichia coli, the thermostability of both proteins was improved. The N-terminal sequence is determinative for the sweetness of the proteins expressed in yeast strains.

Conclusions

Site-directed mutagenesis, modification of the N-terminus of monellin, and without the need of methanol induction in P. pastoris expression system, indicate the possibility for large-scale production of this sweet-tasting protein.

     

Root strength and density decay after felling in a Silver Fir-Norway Spruce stand in the Italian Alps

Aims

Forests induce a mechanical reinforcement of soil, generally quantified in terms of additional root cohesion (c _r ), which decreases due to root decay after felling. The aim of this work is providing new field data on soil reinforcement by roots after trees cutting.

Methods

The present work investigated c _r decay in a mixed Silver Fir-Norway Spruce (Abies alba Mill. Picea abies (L.) Karst.) stand in the Italian Alps over a period of 3 years after felling by monitoring the two c _r driving variables: root tensile resistance and root density.

Results

Results showed that a significant difference in root resistance occurred only 3 years after felling, whereas the decrease in the number of roots was significant in the second year. The degradation process was more rapid in shallower layers and for thinner roots, as a consequence of the pattern of biological activity rate. The reduction of c _r after felling was, for a reference profile depth of 70 cm, 55 % in the first 2 years and another 16 % in the third year.

Conclusions

The findings of this study, providing new data on the decrease of c _r after felling, can be introduced into geotechnical models allowing a better estimation of the stability of forest hillslopes.

     

Genotyping and Persistence of <Emphasis Type="Italic">Candida albicans</Emphasis> from Pregnant Women with Vulvovaginal Candidiasis

Objective

To study Candida albicans genotypes using RAPD and their susceptibility to fluconazole in healthy pregnant women and in vulvovaginal candidiasis (VVC) patients after topical treatment with clotrimazole.

Methods

Vaginal swabs were collected at t = 0 and t = 1 (1 month later) in pregnant women (control group, n = 33), and before (t = 0), at 1 month (t = 1) and at 2 months (t = 2) after clotrimazole treatment in pregnant women with VVC.

Results

Candida albicans was isolated in 30% of healthy pregnant women and 80% of patients with VVC. A high genetic heterogeneity was observed in C. albicans genotypes between individuals. In patients with VVC, topical antifungal treatment with clotrimazole was clinically effective, but only in a 62% C. albicans was eradicated. In patients in which C. albicans was not eradicated, this microorganism persisted for 1 or 2 months after the antifungal treatment. The persistent colonies were not associated with a specific genotype, but they were associated with higher MICs in comparison with colonies isolated from the control group.

Conclusions

Therapy with topical clotrimazole, despite a good clinical outcome, could not eradicate completely C. albicans allowing the persistence of genotypes, with higher MICs to fluconazole. More studies with higher number of patients are needed to validate this preliminary finding.

     

Contribution of direct electron transfer mechanisms to overall electron transfer in microbial fuel cells utilising <Emphasis Type="Italic">Shewanella oneidensis</Emphasis> as biocatalyst

Objectives

To investigate the contribution of direct electron transfer mechanisms to electricity production in microbial fuel cells by physically retaining Shewanella oneidensis cells close to or away from the anode electrode.

Results

A maximum power output of 114 ± 6 mWm^?2 was obtained when cells were retained close to the anode using a dialysis membrane. This was 3.5 times more than when the cells were separated away from the anode. Without the membrane the maximum power output was 129 ± 6 mWm^?2. The direct mechanisms of electron transfer contributed significantly to overall electron transfer from S. oneidensis to electrodes, a result that was corroborated by another experiment where S. oneidensis cells were entrapped in alginate gels.

Conclusion

S. oneidensis transfers electrons primarily by direct electron transfer as opposed to mediated electron transfer.

     

Fungal Keratitis Secondary to <Emphasis Type="Italic">Trametes betulina</Emphasis>: A Case Report and Review of Literature

Purpose

We report the first case of human infection and keratitis secondary to Trametes betulina, a rare filamentous fungus.

Methods

Clinical examination including external and slit-lamp examination and corneal scrapings with microbiologic evaluation were performed on a patient with chronic allergic conjunctivitis, entropion and a long-standing corneal ulcer resistant to treatment.

Results

The culture from the corneal scraping revealed a basidiomycetous fungus which was submitted for identification. DNA extraction with sequencing and analysis of the ITS and D1/D2 regions were performed on the isolate and demonstrated 100% similarity to Lenzites betulina/Trametes betulina. Susceptibility testing demonstrated potent in vitro activity of voriconazole (MIC < 0.03 μg/ml). The patient was treated with voriconazole, and the corneal ulcer and infiltrate resolved. The infection resulted in corneal thinning and a dense central corneal scar. Penetrating keratoplasty was performed 5 months after diagnosis and treatment and revealed stromal scarring without fungal elements.

Conclusion

This is the first reported case of keratitis caused by Trametes betulina. This organism should be considered in the differential diagnosis for rare filamentous fungal keratitis and its treatment with voriconazole also noted.

     

Metabolic profiling identifies trehalose as an abundant and diurnally fluctuating metabolite in the microalga <Emphasis Type="Italic">Ostreococcus tauri</Emphasis>

Introduction

The picoeukaryotic alga Ostreococcus tauri (Chlorophyta) belongs to the widespread group of marine prasinophytes. Despite its ecological importance, little is known about the metabolism of this alga.

Objectives

In this work, changes in the metabolome were quantified when O. tauri was grown under alternating cycles of 12 h light and 12 h darkness.

Methods

Algal metabolism was analyzed by gas chromatography-mass spectrometry. Using fluorescence-activated cell sorting, the bacteria associated with O. tauri were depleted to below 0.1% of total cells at the time of metabolic profiling.

Results

Of 111 metabolites quantified over light–dark cycles, 20 (18%) showed clear diurnal variations. The strongest fluctuations were found for trehalose. With an intracellular concentration of 1.6 mM in the dark, this disaccharide was six times more abundant at night than during the day. This fluctuation pattern of trehalose may be a consequence of starch degradation or of the synchronized cell cycle. On the other hand, maltose (and also sucrose) was below the detection limit (~10 μM). Accumulation of glycine in the light is in agreement with the presence of a classical glycolate pathway of photorespiration. We also provide evidence for the presence of fatty acid methyl and ethyl esters in O. tauri.

Conclusions

This study shows how the metabolism of O. tauri adapts to day and night and gives new insights into the configuration of the carbon metabolism. In addition, several less common metabolites were identified.

     

Development of a novel engineered antibody targeting <Emphasis Type="Italic">Neisseria</Emphasis> species

Objectives

A Neissaria bacterial pilus sugar, bacillosamine, was synthesized and, for the first time, used as a probe to screen a single-chain variable fragment (scFv).

Results

Four Neisseria, Neisseria gonorrhoeae, Neisseria meningitidis, Neisseria sicca and Neisseria subflava, and two negative controls, Streptococcus pneumoniae and Escherichia coli, were tested through ELISA, immunostaining and gold nanoparticle immunological assay. All results indicated that the selected scFv is feasible for the specific detection of Neisseria species via the recognition of bacillosamine.

Conclusions

The recombinant scFv could detect Neisseria strains at 10⁶ CFU/ml.

     

Low temperature and <Emphasis Type="Italic">Daphnia</Emphasis>-associated infochemicals promote colony formation of <Emphasis Type="Italic">Scenedesmus obliquus</Emphasis> and its harvesting

Objective

To explore the combined effects of temperature and Daphnia-associated infochemicals on colony formation of Scenedesmus obliquus to faciliate harvesting the algal biomass.

Results

A three-parameter modified Gaussian model fitted the changes of the number of cells per particle in S. obliquus induced by Daphnia culture filtrate well under any temperature. Decreases in temperature enhanced the induced–colony formation of Scenedesmus. The maximum colony size at 15–25 °C was significantly larger than those at 30–35 °C. An additional 1 or 2 days at low temperature was needed to reach the maximum colony size, which indicates the best harvest time for algal biomass.

Conclusion

Induced-colony formation of Scenedesmus by Daphnia culture filtrate at 15–25 °C is recommended to settle algal cells. This condition facilitates harvesting the biomass.

     

Left ventricular outflow tract velocity time integral outperforms ejection fraction and Doppler-derived cardiac output for predicting outcomes in a select advanced heart failure cohort

Background

Left ventricular outflow tract velocity time integral (LVOT VTI) is a measure of cardiac systolic function and cardiac output. Heart failure patients with low cardiac output are known to have poor cardiovascular outcomes. Thus, extremely low LVOT VTI may predict heart failure patients at highest risk for mortality.

Methods

Patients with heart failure and extremely low LVOT VTI were identified from a single-center database. Baseline characteristics and heart failure related clinical outcomes (death, LVAD) were obtained at 12 months. Correlation between clinical endpoints and the following variables were analyzed: ejection fraction (EF), pulmonary artery systolic pressure (PASP), NYHA class, renal function, Doppler cardiac output (CO), and LVOT VTI.

Results

Study cohort consisted of 100 patients. At the 12-month follow up period, 30 events (28 deaths, 2 LVADs) were identified. Occurrence of death and LVAD implantation was statistically associated with a lower LVOT VTI (p = 0.039) but not EF (p = 0.169) or CO (p = 0.217). In multivariate analysis, LVOT VTI (p = 0.003) remained statistically significant, other significant variables were age (p = 0.033) and PASP (p = 0.022). Survival analysis by LVOT VTI tertile demonstrated an unadjusted hazard ratio of 4.755 (CI 1.576-14.348, p = 0.006) for combined LVAD and mortality at one year.

Conclusions

Extremely low LVOT VTI strongly predicts adverse outcomes and identifies patients who may benefit most from advanced heart failure therapies.

     

Asymmetric reduction of ketopantolactone using a strictly (<Emphasis Type="Italic">R</Emphasis>)-stereoselective carbonyl reductase through efficient NADPH regeneration and the substrate constant-feeding strategy

Objectives

To characterize a recombinant carbonyl reductase from Saccharomyces cerevisiae (SceCPR1) and explore its use in asymmetric synthesis of (R)-pantolactone [(R)-PL].

Results

The NADPH-dependent SceCPR1 exhibited strict (R)-enantioselectivity and high activity in the asymmetric reduction of ketopantolactone (KPL) to (R)-PL. Escherichia coli, coexpressing SceCPR1 and glucose dehydrogenase from Exiguobacterium sibiricum (EsGDH), was constructed to fulfill efficient NADPH regeneration. During the whole-cell catalyzed asymmetric reduction of KPL, the spontaneous hydrolysis of KPL significantly affected the yield of (R)-PL, which was effectively alleviated by the employment of the substrate constant-feeding strategy. The established whole-cell bioreduction for 6 h afforded 458 mM (R)-PL with the enantiomeric excess value of >99.9% and the yield of 91.6%.

Conclusions

Escherichia coli coexpressing SceCPR1 and EsGDH efficiently catalyzed the asymmetric synthesis of (R)-PL through the substrate constant-feeding strategy.

     

High intensity smoking cessation interventions: Cardiac patients of low socioeconomic status and low intention to quit profit most

Background

Without assistance, smokers being admitted to the hospital for coronary heart disease often return to regular smoking within a year.

Objective

This study assessed the 12-month effectiveness of a telephone and a face-to-face counselling intervention on smoking abstinence among cardiac patients. Differential effects for subgroups varying in their socioeconomic status and intention to quit smoking were also studied.

Methods

A randomised controlled trial was used. During hospital stay, smokers hospitalised for coronary heart disease were assigned to usual care (n = 245), telephone counselling (n = 223) or face-to-face counselling (n = 157). Eligible patients were allocated to an intervention counselling group and received nicotine patches. After 12 months, self-reported continued abstinence was assessed and biochemically verified in quitters. Effects on smoking abstinence were tested using multilevel logistic regression analyses applying the intention-to-treat approach.

Results

Compared with usual care, differential effects of telephone and face-to-face counselling on continued abstinence were found in patients with a low socioeconomic status and in patients with a low quit intention. For these patients, telephone counselling increased the likelihood of abstinence threefold (OR = 3.10, 95?% CI 1.32–7.31, p = 0.01), whereas face-to-face counselling increased this likelihood fivefold (OR = 5.30, 95?% CI 2.13–13.17, p < 0.001). Considering the total sample, the interventions did not result in stronger effects than usual care.

Conclusion

Post-discharge telephone and face-to-face counselling interventions increased smoking abstinence rates at 12 months compared with usual care among cardiac patients of low socioeconomic status and low quit intentions. The present study indicates that patients of high socioeconomic status and high quit motivation require different cessation approaches.

     

Purging behaviors relate to impaired subjective sleep quality in female patients with anorexia nervosa: a prospective observational study

Background

We examined how purging behaviors relate to subjective sleep quality and sleep patterns and how symptoms of disordered eating behaviors relate to global sleep quality in female patients with anorexia nervosa (AN).

Methods

Participants were new consecutive female inpatients with a primary diagnosis of AN admitted to the Department of Psychosomatic Medicine at Kohnodai Hospital between June 26 and December 25, 2015. We recorded patients’ habitual eating behaviors, laxative overuse, or uretic misuse, and administered the Japanese versions of the Pittsburgh Sleep Quality Index (PSQI-J) and Center for Epidemiologic Studies Depression Scale. Raw PSQI-J data were used to determine sleep patterns (sleep-onset time, wake-up time, and sleep duration). To examine how purging behaviors related to sleep quality, we compared variables between AN restricting type (ANr) and AN binge-eating/purging type (ANbp). Spearman’s rank correlation analysis was used to examine which potential factors influence global PSQI-J score.

Results

Participants were 20 patients, of whom 12 had ANbp. Two ANr patients (25%) had global PSQI-J scores greater than 5, compared to 9 ANbp patients (75%; P < 0.05). Circadian rhythm disruption and abnormal sleep duration were significantly greater in ANbp patients than in ANr patients (P < 0.05). Global PSQI-J was significantly correlated with a diagnosis of ANbp (ρ = 0.525; P < 0.05), vomiting (ρ = 0.561; P < 0.05), and duration of illness (ρ = 0.536; P < 0.05).

Conclusions

ANbp patients had worse global sleep quality and greater disrupted sleep than did ANr patients. This suggests that treatments focusing on sleep would be useful, especially for ANbp patients. Furthermore, vomiting and duration of illness should be considered essential factors related to impaired global sleep quality.

Trial registration

Not applicable.