Probiotic interventions promote metabolic health in high fat-fed hamsters in association with gut microbiota and endocannabinoidome alterations

Probiotics represent a promising tool to improve metabolic health, including lipid profiles and cholesterol levels. Modulation of the gut microbiome and the endocannabinoidome - two interrelated systems involved in several metabolic processes influenced by probiotics - has been proposed as a potential mechanism of action. This study establishes the impact of probiotics on metabolic health, gut microbiota composition and endocannabinoidome mediators in an animal model of hypercholesterolaemia. Syrian hamsters were fed either a low-fat low-cholesterol or high-fat high-cholesterol (HFHC) diet to induce hypercholesterolaemia and gavaged for 6 weeks with either Lactobacillus acidophilus CL1285, Lactiplantibacillus plantarum CHOL-200 or a combination of the two. Globally, probiotic interventions ameliorated, at least partially, lipid metabolism in HFHC-fed hamsters. The interventions, especially those including L. acidophilus, modified the gut microbiota composition of the small intestine and caecum in ways suggesting reversal of HFHC-induced dysbiosis. Several associations were observed between changes in gut microbiota composition and endocannabinoidome mediators following probiotic interventions and both systems were also associated with improved metabolic health parameters. For instance, potential connexions between the Eubacteriaceae and Deferribacteraceae families, levels of 2‑palmitoylglycerol, 2‑oleoylglycerol, 2‑linoleoylglycerol or 2‑eicosapentaenoylglycerol and improved lipid profiles were found. Altogether, our results suggest a potential crosstalk between gut microbiota and the endocannabinoidome in driving metabolic benefits associated with probiotics, especially those including L. acidophilus, in an animal model of hypercholesterolaemia.

Analysis of the oral microbiome during hormonal cycle and its alterations in menopausal women: the "AMICA" project

The maintenance of human health is dependent on a symbiotic relationship between humans and associated bacteria. The diversity and abundance of each habitat's signature microbes vary widely among body areas and among them the oral microbiome plays a key role. Significant changes in the oral cavity, predominantly at salivary and periodontal level, have been associated with changes in estrogen levels. However, whether the oral microbiome is affected by hormonal level alterations is understudied. Hence the main objective pursued by AMICA project was to characterize the oral microbiome (saliva) in healthy women through: profiling studies using "omics" technologies (NMR-based metabolomics, targeted lipidomics by LC-MS, metagenomics by NGS); SinglePlex ELISA assays; glycosidase activity analyses and bioinformatic analysis. For this purpose, thirty-nine medically healthy women aged 26-77 years (19 with menstrual cycle and 20 in menopause) were recruited. Participants completed questionnaires assessing detailed medical and medication history and demographic characteristics. Plasmatic and salivary levels of sexual hormones were assessed (FSH, estradiol, LH and progesteron) at day 3 and 14 for women with menstrual cycle and only once for women in menopause. Salivary microbiome composition was assessed through meta-taxonomic 16S sequencing and overall, the salivary microbiome of most women remained relatively stable throughout the menstrual cycle and in menopause. Targeted lipidomics and untargeted metabolomics profiling were assessed through the use of LC-MS and NMR spectroscopy technologies, respectively and significant changes in terms of metabolites were identified in saliva of post-menopausal women in comparison to cycle. Moreover, glycosyl hydrolase activities were screened and showed that the β-D-hexosaminidase activity was the most present among those analyzed. Although this study has not identified significant alterations in the composition of the oral microbiome, multiomics analysis have revealed a strong correlation between 2-AG and α-mannosidase. In conclusion, the use of a multidisciplinary approach to investigate the oral microbiome of healthy women provided some indication about microbiome-derived predictive biomarkers that could be used in the future for developing new strategies to help to re-establish the correct hormonal balance in post-menopausal women.

In vivo transcriptomic profiling using cell encapsulation identifieseffector pathways of systemic aging

Sustained exposure to a young systemic environment rejuvenates aged organisms and promotes cellular function. However, due to the intrinsic complexity of tissues it remains challenging to pinpoint niche-independent effects of circulating factors on specific cell populations. Here, we describe a method for the encapsulation of human and mouse skeletal muscle progenitors in diffusible polyethersulfone hollow fiber capsules that can be used to profile systemic aging in vivo independent of heterogeneous short-range tissue interactions. We observed that circulating long-range signaling factors in the old systemic environment lead to an activation of Myc and E2F transcription factors, induce senescence, and suppress myogenic differentiation. Importantly, in vitro profiling using young and old serum in 2D culture does not capture all pathways deregulated in encapsulated cells in aged mice. Thus, in vivo transcriptomic profiling using cell encapsulation allows for the characterization of effector pathways of systemic aging with unparalleled accuracy.

Longitudinal Human Milk miRNA Composition over the First 3 mo of Lactation in a Cohort of Healthy Mothers Delivering Term Infants

BACKGROUND

MicroRNAs (miRNAs) are small noncoding RNAs involved in posttranscriptional regulation. miRNAs can be secreted and found in many body fluids, and although they are particularly abundant in breastmilk, their functions remain elusive. Human milk (HM) miRNAs start to raise considerable interest, but a comprehensive understanding of the repertoire and expression profiles along lactation has not been well characterized.

OBJECTIVES

This study aimed to characterize the longitudinal profile of HM miRNA between the second week and third month postpartum.

METHODS

We used a new sensitive technology to measure HM miRNAs in a cohort of 44 French mothers [mean ± SD age: 31 ± 3.5; BMI (in kg/m2) 21.8 ± 2.3] who delivered at term and provided HM samples at 3 time points (17 ± 3 d, 60 ± 3 d, and 90 ± 3 d) during follow-up visits.

RESULTS

We detected 685 miRNAs, of which 35 showed a high and stable expression along the lactation period analyzed. We also described for the first time a set of 11 miRNAs with a dynamic expression profile. To gain insight into the potential functional relevance of this set of miRNAs, we selected miR-3126 and miR-3184 to treat undifferentiated Caco-2 human intestinal cells and then assessed differentially expressed genes and modulation of related biological pathways.

CONCLUSIONS

Overall, our study provides new insights into HM miRNA composition and, to our knowledge, the first description of its longitudinal dynamics in mothers who delivered at term. Our in vitro results obtained in undifferentiated Caco-2 human intestinal cells transfected with HM miRNAs also provide further support to the hypothesized mother-to-neonate signaling role of HM miRNAs. This trial was registered at clinicaltrials.gov as NCT01894893.

Whole-genome sequencing analysis of semi-supercentenarians

Extreme longevity is the paradigm of healthy aging as individuals who reached the extreme decades of human life avoided or largely postponed all major age-related diseases. In this study, we sequenced at high coverage (90X) the whole genome of 81 semi-supercentenarians and supercentenarians [105+/110+] (mean age: 106.6 ± 1.6) and of 36 healthy unrelated geographically matched controls (mean age 68.0 ± 5.9) recruited in Italy. The results showed that 105+/110+ are characterized by a peculiar genetic background associated with efficient DNA repair mechanisms, as evidenced by both germline data (common and rare variants) and somatic mutations patterns (lower mutation load if compared to younger healthy controls). Results were replicated in a second independent cohort of 333 Italian centenarians and 358 geographically matched controls. The genetics of 105+/110+ identified DNA repair and clonal haematopoiesis as crucial players for healthy aging and for the protection from cardiovascular events.

Genomic history of the Italian population recapitulates key evolutionary dynamics of both Continental and Southern Europeans

BACKGROUND

The cline of human genetic diversity observable across Europe is recapitulated at a micro-geographic scale by variation within the Italian population. Besides resulting from extensive gene flow, this might be ascribable also to local adaptations to diverse ecological contexts evolved by people who anciently spread along the Italian Peninsula. Dissecting the evolutionary history of the ancestors of present-day Italians may thus improve the understanding of demographic and biological processes that contributed to shape the gene pool of European populations. However, previous SNP array-based studies failed to investigate the full spectrum of Italian variation, generally neglecting low-frequency genetic variants and examining a limited set of small effect size alleles, which may represent important determinants of population structure and complex adaptive traits. To overcome these issues, we analyzed 38 high-coverage whole-genome sequences representative of population clusters at the opposite ends of the cline of Italian variation, along with a large panel of modern and ancient Euro-Mediterranean genomes.

RESULTS

We provided evidence for the early divergence of Italian groups dating back to the Late Glacial and for Neolithic and distinct Bronze Age migrations having further differentiated their gene pools. We inferred adaptive evolution at insulin-related loci in people from Italian regions with a temperate climate, while possible adaptations to pathogens and ultraviolet radiation were observed in Mediterranean Italians. Some of these adaptive events may also have secondarily modulated population disease or longevity predisposition.

CONCLUSIONS

We disentangled the contribution of multiple migratory and adaptive events in shaping the heterogeneous Italian genomic background, which exemplify population dynamics and gene-environment interactions that played significant roles also in the formation of the Continental and Southern European genomic landscapes.

Clostridium difficile: Investigating Transmission Patterns Between Infected and Colonized Patients Using Whole Genome Sequencing

Background

Whole genome sequencing (WGS) studies can enhance our understanding of the role of patients with asymptomatic Clostridium difficile colonization in transmission.

Methods

Isolates obtained from patients with Clostridium difficile infection (CDI) and colonization identified in a study conducted during 2006-2007 at 6 Canadian hospitals underwent typing by pulsed-field gel electrophoresis, multilocus sequence typing, and WGS. Isolates from incident CDI cases not in the initial study were also sequenced where possible. Ward movement and typing data were combined to identify plausible donors for each CDI case, as defined by shared time and space within predefined limits. Proportions of plausible donors for CDI cases that were colonized, infected, or both were examined.

Results

Five hundred fifty-four isolates were sequenced successfully, 353 from colonized patients and 201 from CDI cases. The NAP1/027/ST1 strain was the most common strain, found in 124 (62%) of infected and 92 (26%) of colonized patients. A donor with a plausible ward link was found for 81 CDI cases (40%) using WGS with a threshold of ≤2 single nucleotide polymorphisms to determine relatedness. Sixty-five (32%) CDI cases could be linked to both infected and colonized donors. Exclusive linkages to infected and colonized donors were found for 28 (14%) and 12 (6%) CDI cases, respectively.

Conclusions

Colonized patients contribute to transmission, but CDI cases are more likely linked to other infected patients than colonized patients in this cohort with high rates of the NAP1/027/ST1 strain, highlighting the importance of local prevalence of virulent strains in determining transmission dynamics.

Mitochondrial oxidative capacity and NAD+ biosynthesis are reduced in human sarcopenia across ethnicities

The causes of impaired skeletal muscle mass and strength during aging are well-studied in healthy populations. Less is known on pathological age-related muscle wasting and weakness termed sarcopenia, which directly impacts physical autonomy and survival. Here, we compare genome-wide transcriptional changes of sarcopenia versus age-matched controls in muscle biopsies from 119 older men from Singapore, Hertfordshire UK and Jamaica. Individuals with sarcopenia reproducibly demonstrate a prominent transcriptional signature of mitochondrial bioenergetic dysfunction in skeletal muscle, with low PGC-1α/ERRα signalling, and downregulation of oxidative phosphorylation and mitochondrial proteostasis genes. These changes translate functionally into fewer mitochondria, reduced mitochondrial respiratory complex expression and activity, and low NAD+ levels through perturbed NAD+ biosynthesis and salvage in sarcopenic muscle. We provide an integrated molecular profile of human sarcopenia across ethnicities, demonstrating a fundamental role of altered mitochondrial metabolism in the pathological loss of skeletal muscle mass and function in older people.

Bisphenol A binding promiscuity: A virtual journey through the universe of proteins

Significant efforts are currently being made to move toxicity testing from animal experimentation to human relevant, mechanism-based approaches. In this context, the identification of molecular target(s) responsible for mechanisms of action is an essential step. Inspired by the recent concept of polypharmacology (the ability of drugs to interact with multiple targets) we argue that whole proteome virtual screening might become a breakthrough tool in toxicology reflecting the real complexity of chemical-biological interactions. Therefore, we investigated the value of performing ligand-protein binding prediction screening across the full proteome to identify new mechanisms of action for food chemicals. We applied the new approach to make a broader comparison between bisphenol A (BPA) (food-packaging chemical) and the endogenous estrogen, 17β-estradiol (EST). Applying a novel high-throughput ligand-protein binding prediction tool (BioGPS) by the Amazon Web Services (AWS) cloud (to speed-up the calculation), we investigated the value of performing in silico screening across the full proteome (all human and rodent x-ray protein structures available in the Protein Data Bank). The strong correlation between in silico predictions and available in vitro data demonstrates the high predictive power of the method used. The most striking results obtained was that BPA was predicted to bind to many more proteins than the ones already known, most of which were common to EST. Our findings provide a new and unprecedented insight on the complexity of chemical-protein interactions, highlighting the binding promiscuity of BPA and its broader similarity compared to the female sex hormone, EST.

AMPK promotes induction of the tumor suppressor FLCN through activation of TFEB independently of mTOR

AMPK is a central regulator of energy homeostasis. AMPK not only elicits acute metabolic responses but also promotes metabolic reprogramming and adaptations in the long-term through regulation of specific transcription factors and coactivators. We performed a whole-genome transcriptome profiling in wild-type (WT) and AMPK-deficient mouse embryonic fibroblasts (MEFs) and primary hepatocytes that had been treated with 2 distinct classes of small-molecule AMPK activators. We identified unique compound-dependent gene expression signatures and several AMPK-regulated genes, including folliculin (Flcn), which encodes the tumor suppressor FLCN. Bioinformatics analysis highlighted the lysosomal pathway and the associated transcription factor EB (TFEB) as a key transcriptional mediator responsible for AMPK responses. AMPK-induced Flcn expression was abolished in MEFs lacking TFEB and transcription factor E3, 2 transcription factors with partially redundant function; additionally, the promoter activity of Flcn was profoundly reduced when its putative TFEB-binding site was mutated. The AMPK-TFEB-FLCN axis is conserved across species; swimming exercise in WT zebrafish induced Flcn expression in muscle, which was significantly reduced in AMPK-deficient zebrafish. Mechanistically, we have found that AMPK promotes dephosphorylation and nuclear localization of TFEB independently of mammalian target of rapamycin activity. Collectively, we identified the novel AMPK-TFEB-FLCN axis, which may function as a key cascade for cellular and metabolic adaptations.—Collodet, C., Foretz, M., Deak, M., Bultot, L., Metairon, S., Viollet, B., Lefebvre, G., Raymond, F., Parisi, A., Civiletto, G., Gut, P., Descombes, P., Sakamoto, K. AMPK promotes induction of the tumor suppressor FLCN through activation of TFEB independently of mTOR.

Aging Disrupts Muscle Stem Cell Function by Impairing Matricellular WISP1 Secretion from Fibro-Adipogenic Progenitors

Research on age-related regenerative failure of skeletal muscle has extensively focused on the phenotypes of muscle stem cells (MuSCs). In contrast, the impact of aging on regulatory cells in the MuSC niche remains largely unexplored. Here, we demonstrate that aging impairs the function of mouse fibro-adipogenic progenitors (FAPs) and thereby indirectly affects the myogenic potential of MuSCs. Using transcriptomic profiling, we identify WNT1 Inducible Signaling Pathway Protein 1 (WISP1) as a FAP-derived matricellular signal that is lost during aging. WISP1 is required for efficient muscle regeneration and controls the expansion and asymmetric commitment of MuSCs through Akt signaling. Transplantation of young FAPs or systemic treatment with WISP1 restores the myogenic capacity of MuSCs in aged mice and rescues skeletal muscle regeneration. Our work establishes that loss of WISP1 from FAPs contributes to MuSC dysfunction in aged skeletal muscles and demonstrates that this mechanism can be targeted to rejuvenate myogenesis.

The EcoChip: A Wireless Multi-Sensor Platform for Comprehensive Environmental Monitoring

This paper presents the EcoChip, a new system based on the state-of-the-art electro-chemical impedance (EIS) technologies allowing the growth of single strain organisms isolated from northern habitats. This portable system is a complete and autonomous wireless platform designed to monitor and cultivate microorganisms directly sampled from their natural environment, particularly from harsh northern environments. Using 96-well plates, the EcoChip can be used in the field for real-time monitoring of bacterial growth. Manufactured with high-quality electronic components, this new EIS monitoring system is designed to function at a low excitation voltage signal to avoid damaging the cultured cells. The high-precision calibration network leads to high-precision results, even in the most limiting contexts. Luminosity, humidity, and temperature can also be monitored with the addition of appropriate sensors. Access to robust data storage systems and power supplies is an obvious limitation for northern research. That is why the EcoChip is equipped with a flash memory that can store data over long periods of time. To resolve the power issue, a low-power micro-controller and a power management unit control and supply all electronic building blocks. Data stored in the EcoChip's flash memory can be transmitted through a transceiver whenever a receiver is located within the functional transmission range. In this paper, we present the measured performance of the system, along with results from laboratory tests in vitro and from two field tests. The EcoChip has been utilized to collect bio-environemental data in the field from the northern soils and ecosystems of Kuujjuarapik and Puvirnituq, during two expeditions, in 2017 and 2018, respectively. We show that the EcoChip can effectively carry out EIS analyses over an excitation frequency ranging from 750 Hz to 10 kHz with an accuracy of 2.35%. The overall power consumption of the system was 140.4 mW in normal operating mode and 81 μW in sleep mode. The proper development of the isolated bacteria was confirmed through deoxyribonucleic acid sequencing, indicating that bacteria thrive in the EcoChip's culture wells while the growing conditions are successfully gathered and stored.

Biomarkers of browning of white adipose tissue and their regulation during exercise- and diet-induced weight loss

BACKGROUND

A hypothesis exists whereby an exercise- or dietary-induced negative energy balance reduces human subcutaneous white adipose tissue (scWAT) mass through the formation of brown-like adipocyte (brite) cells. However, the validity of biomarkers of brite formation has not been robustly evaluated in humans, and clinical data that link brite formation and weight loss are sparse.

OBJECTIVES

We used rosiglitazone and primary adipocytes to stringently evaluate a set of biomarkers for brite formation and determined whether the expression of biomarker genes in scWAT could explain the change in body composition in response to exercise training combined with calorie restriction in obese and overweight women (n = 79).

DESIGN

Gene expression was derived from exon DNA microarrays and preadipocytes from obesity-resistant and -sensitive mice treated with rosiglitazone to generate candidate brite biomarkers from a microarray. These biomarkers were evaluated against data derived from scWAT RNA from obese and overweight women before and after supervised exercise 5 d/wk for 16 wk combined with modest calorie restriction (∼0.84 MJ/d).

RESULTS

Forty percent of commonly used brite gene biomarkers exhibited an exon or strain-specific regulation. No biomarkers were positively related to weight loss in human scWAT. Greater weight loss was significantly associated with less uncoupling protein 1 expression (P = 0.006, R(2) = 0.09). In a follow-up global analysis, there were 161 genes that covaried with weight loss that were linked to greater CCAAT/enhancer binding protein α activity (z = 2.0, P = 6.6 × 10(-7)), liver X receptor α/β agonism (z = 2.1, P = 2.8 × 10(-7)), and inhibition of leptin-like signaling (z = -2.6, P = 3.9 × 10(-5)).

CONCLUSION

We identify a subset of robust RNA biomarkers for brite formation and show that calorie-restriction-mediated weight loss in women dynamically remodels scWAT to take on a more-white rather than a more-brown adipocyte phenotype.

Loss of fibronectin from the aged stem cell niche affects the regenerative capacity of skeletal muscle in mice

Age-related changes in the niche have long been postulated to impair the function of somatic stem cells. Here we demonstrate that the aged stem cell niche in skeletal muscle contains substantially reduced levels of fibronectin (FN), leading to detrimental consequences for the function and maintenance of muscle stem cells (MuSCs). Deletion of the gene encoding FN from young regenerating muscles replicates the aging phenotype and leads to a loss of MuSC numbers. By using an extracellular matrix (ECM) library screen and pathway profiling, we characterize FN as a preferred adhesion substrate for MuSCs and demonstrate that integrin-mediated signaling through focal adhesion kinase and the p38 mitogen-activated protein kinase pathway is strongly de-regulated in MuSCs from aged mice because of insufficient attachment to the niche. Reconstitution of FN levels in the aged niche remobilizes stem cells and restores youth-like muscle regeneration. Taken together, we identify the loss of stem cell adhesion to FN in the niche ECM as a previously unknown aging mechanism.

Protein-leucine ingestion activates a regenerative inflammo-myogenic transcriptome in skeletal muscle following intense endurance exercise

Protein-leucine supplement ingestion following strenuous endurance exercise accentuates skeletal-muscle protein synthesis and adaptive molecular responses, but the underlying transcriptome is uncharacterized. In a randomized single-blind triple-crossover design, 12 trained men completed 100 min of high-intensity cycling then ingested 70/15/180/30 g protein-leucine-carbohydrate-fat (15LEU), 23/5/180/30 g (5LEU), or 0/0/274/30 g (CON) beverages during the first 90 min of a 240 min recovery period. Vastus lateralis muscle samples (30 and 240 min postexercise) underwent transcriptome analysis by microarray followed by bioinformatic analysis. Gene expression was regulated by protein-leucine in a dose-dependent manner affecting the inflammatory response and muscle growth and development. At 30 min, 15LEU and 5LEU vs. CON activated transcriptome networks with gene-set functions involving cell-cycle arrest (Z-score 2.0-2.7, P < 0.01), leukocyte maturation (1.7, P = 0.007), cell viability (2.4, P = 0.005), promyogenic networks encompassing myocyte differentiation and myogenin (MYOD1, MYOG), and a proteinaceous extracellular matrix, adhesion, and development program correlated with plasma lysine, arginine, tyrosine, taurine, glutamic acid, and asparagine concentrations. High protein-leucine dose (15LEU-5LEU) activated an IL-1I-centered proinflammatory network and leukocyte migration, differentiation, and survival functions (2.0-2.6, <0.001). By 240 min, the protein-leucine transcriptome was anti-inflammatory and promyogenic (IL-6, NF- β, SMAD, STAT3 network inhibition), with overrepresented functions including decreased leukocyte migration and connective tissue development (-1.8-2.4, P < 0.01), increased apoptosis of myeloid and muscle cells (2.2-3.0, P < 0.002), and cell metabolism (2.0-2.4, P < 0.01). The analysis suggests protein-leucine ingestion modulates inflammatory-myogenic regenerative processes during skeletal muscle recovery from endurance exercise. Further cellular and translational research is warranted to validate amino acid-mediated myeloid and myocellular mechanisms within skeletal-muscle functional plasticity.

Effect of a mixture of bovine milk oligosaccharides, Lactobacillus rhamnosus NCC4007 and long-chain polyunsaturated fatty acids on catch-up growth of intra-uterine growth-restricted rats

AIM

To investigate the effect of a nutritional mixture (bovine milk oligosaccharides, Lactobacillus rhamnosus NCC4007, arachidonic and docosahexaenoic acid) on growth of intrauterine growth-restricted (IUGR) rats.

METHODS

IUGR was induced by maternal food restriction. The offspring (males and females) were assigned to: REF (non-IUGR, no mixture), IUGRc (IUGR, no mixture), or IUGRmx (IUGR, mixture). The mixture was given from day 7 to day 58, when tissues and plasma from half of the animals were collected for hormones, metabolites and microarray analysis. The rest received a high-fat diet (HFD) until day 100. Glucose tolerance was measured at 56 and 98 days, and body fat content at 21, 52 and 97 days.

RESULTS

IUGRmx had the greatest growth during lactation, but from day 22 to day 54, both IUGR groups gained less body weight than the REF (P < 0.05). In the short-term (58 days), IUGRmx tended to be longer (P = 0.06) and had less body fat (P = 0.03) than IUGRc. These differences were not seen after HFD. Microarray analysis of hepatic mRNA expression at 58 and 100 days revealed a gender-dependent treatment effect, and expression of genes related to lipid metabolism was the most affected. Twelve of these genes were selected for studying differences in DNA methylation in the promoter region, for some, we observed age- and gender-related differences but none because of treatment.

CONCLUSION

The nutritional intervention promoted catch-up growth and normalized excessive adiposity in IUGR animals at short-term. The benefits did not extend after a period of HFD. IUGR and early diet had gender-dependent effects on hepatic gene expression.

Nasopharyngeal carriage of individual Streptococcus pneumoniae serotypes during pediatric radiologically confirmed community acquired pneumonia following PCV7 introduction in Switzerland

BACKGROUND

Community-acquired pneumonia (CAP) is a serious cause of morbidity among children in developed countries. The real impact of 7-valent pneumococcal conjugate vaccine (PCV7) on pneumococcal pneumonia is difficult to assess accurately.

METHODS

Children aged ≤16 years with clinical and radiological pneumonia were enrolled in a multicenter prospective study. Children aged ≤16 years admitted for a minor elective surgery was recruited as controls. Nasopharyngeal samples for PCR serotyping of S. pneumoniae were obtained in both groups. Informations on age, gender, PCV7 vaccination status, day care/school attendance, siblings, tobacco exposure were collected.

RESULTS

In children with CAP (n=236), 54% of the nasopharyngeal swabs were PCR-positive for S. pneumoniae compared to 32% in controls (n=105) (p=0.003). Serotype 19A was the most common pneumococcal serotype carried in children with CAP (13%) and in controls (15%). Most common serotypes were non-vaccine types (39.4% for CAP and 47.1% for controls) and serotypes included only in PCV13 (32.3% for CAP and 23.5% for controls). There was no significant difference in vaccine serotype distribution between the two groups. In fully vaccinated children with CAP, the proportion of serotypes carried only in PCV13 was higher (51.4%) than in partially vaccinated or non vaccinated children (27.6% and 28.6% respectively, p=0.037).

CONCLUSIONS

Two to 4 years following introduction of PCV7, predominant S. pneumoniae serotypes carried in children with CAP were non PCV7 serotypes, and the 6 new serotypes included in PCV13 accounted for 51.4% of carried serotypes in fully vaccinated children.

Effects of increase in fish oil intake on intestinal eicosanoids and inflammation in a mouse model of colitis

BACKGROUND

Inflammatory bowel diseases (IBD) are chronic intestinal inflammatory diseases affecting about 1% of western populations. New eating behaviors might contribute to the global emergence of IBD. Although the immunoregulatory effects of omega-3 fatty acids have been well characterized in vitro, their role in IBD is controversial.

METHODS

The aim of this study was to assess the impact of increased fish oil intake on colonic gene expression, eicosanoid metabolism and development of colitis in a mouse model of IBD. Rag-2 deficient mice were fed fish oil (FO) enriched in omega-3 fatty acids i.e. EPA and DHA or control diet for 4 weeks before colitis induction by adoptive transfer of naïve T cells and maintained in the same diet for 4 additional weeks. Onset of colitis was monitored by colonoscopy and further confirmed by immunological examinations. Whole genome expression profiling was made and eicosanoids were measured by HPLC-MS/MS in colonic samples.

RESULTS

A significant reduction of colonic proinflammatory eicosanoids in FO fed mice compared to control was observed. However, neither alteration of colonic gene expression signature nor reduction in IBD scores was observed under FO diet.

CONCLUSION

Thus, increased intake of dietary FO did not prevent experimental colitis.

Telomeric gene deletion and intrachromosomal amplification in antimony-resistant Leishmania

Antimonials are still the mainstay of treatment against leishmaniasis but drug resistance is increasing. We carried out short read next-generation sequencing (NGS) and comparative genomic hybridization (CGH) of three independent Leishmania major antimony-resistant mutants. Copy number variations were consistently detected with both NGS and CGH. A major attribute of antimony resistance was a novel terminal deletion of variable length (67 kb to 204 kb) of the polyploid chromosome 31 in the three mutants. Terminal deletions in two mutants occurred at the level of inverted repeated sequences. The AQP1 gene coding for an aquaglyceroporin was part of the deleted region and its transfection into resistant mutants reverted resistance to SbIII. We also highlighted an intrachromosomal amplification of a subtelomeric locus on chromosome 34 in one mutant. This region encoded for ascorbate-dependent peroxidase (APX) and glucose-6-phosphate dehydrogenase (G6PDH). Overexpression of these genes in revertant backgrounds demonstrated resistance to SbIII and protection from reactive oxygen species (ROS). Generation of a G6PDH null mutant in one revertant exhibited SbIII sensitivity and a decreased protection of ROS. Our genomic analyses and functional validation highlighted novel genomic rearrangements, functionally important resistant loci and the implication of new genes in antimony resistance in Leishmania.

Six weeks' sebacic acid supplementation improves fasting plasma glucose, HbA1c and glucose tolerance in db/db mice

AIM

To investigate the impact of chronic ingestion of sebacic acid (SA), a 10-carbon medium-chain dicarboxylic acid, on glycaemic control in a mouse model of type 2 diabetes (T2D).

METHODS

Three groups of 15 db/db mice were fed for 6 weeks either a chow diet (Ctrl) or a chow diet supplemented with 1.5 or 15% (SA(1.5%) and SA(15%) , respectively) energy from SA. Fasting glycaemia was measured once a week and HbA1c before and after supplementation. An oral glucose tolerance test (OGTT) was performed at the end of the supplementation. Gene expression was determined by transcriptomic analysis on the liver of the Ctrl and SA(15%) groups.

RESULTS

After 42 days of supplementation, fasting glycaemia and HbA1c were ∼70 and 25% lower in the SA(15%) group compared with the other groups showing a beneficial effect of SA on hyperglycaemia. During OGTT, plasma glucose area under the curve was reduced after SA(15%) compared with the other groups. This effect was associated with a tendency for an improved insulin response. In the liver, Pck1 and FBP mRNA were statistically decreased in the SA(15%) compared with Ctrl suggesting a reduced hepatic glucose output induced by SA.

CONCLUSION

Dietary supplementation of SA largely improves glycaemic control in a mouse model of T2D. This beneficial effect may be due to (i) an improved glucose-induced insulin secretion and (ii) a reduced hepatic glucose output.

Strategies for improving production and purification of a recombinant protein: rP30 of Toxoplasma gondii expressed in the yeast Schizosaccharomyces pombe

Many problems concerned with the production and the purification of recombinant proteins must be addressed prior to launching an industrial production process. Among these problems, attention is focused on low-level expression that complicates the purification step and can jeopardise the process. The expression of a membrane protein, rP30, of Toxoplasma gondii in the yeast Schizosaccharomyces pombe led to a secretion of only 0.5 microg ml(-1). In order to obtain a sufficient quantity for biochemical characterization and evaluation in vitro diagnostic test development, strategies for both production and purification had to be optimized. First, the influence of four nitrogen sources (three peptones and yeast extract) on the growth rate, but also on the separation between the protein and the components of the fermentation broth was assessed. Second, batch and fed-batch fermentations were compared in terms of final biomass and rP30 concentrations. Third, three different protocols that included fixed and expanded bed ion exchange chromatography were compared for processing a large volume of feedstock. By using the most appropriate strategies, i.e. fed-batch fermentation, capture on EBA cation exchanger and affinity chromatography polishing, a purification factor of 1778 and a yield of 49% were achieved. These performances allowed a 12.5-fold increase for the overall rP30 process productivity.

[Haematological complications of prostatic cancer: 2 cases, one revealing the neoplasia]

INTRODUCTION

We report two cases of patients with prostate cancer who underwent haematological complications from the disease.

CLINICAL CASES

Diffuse intravascular coagulopathy (with thrombopenia) was observed in two patients (55 and 59 years-old) diagnosed with prostate cancer. In one patient who had normal prostate at clinical examination, thrombopenia with incomplete diffuse intravascular coagulopathy and biological inflammatory led to diagnosis. It was initially controlled by hormonal therapy and secondary by chemotherapy. In the other patient diffuse intravascular coagulopathy followed introduction of hormonal therapy and lead to the patient's death.

DISCUSSION

Patients with metastatic hormone-refractory prostate carcinoma may have life-threatening coagulation complications due to their disease. Diffuse intravascular coagulopathy is the most frequent coagulation complication. Other coagulopathies associated with prostate cancer are thrombocytopenic thrombotic purpura, thrombosis, Trousseau's syndrome and acquired factor VIII inhibitor development. Usually these haematological manifestations complicate the course of the disease and appear to have a bad prognosis. But thrombopenia or haematologic features may lead to the diagnosis of medullary metastatic prostatic cancer, even if the prostate appears normal at the initial clinical examination.

The development of a high-density canine microarray

DNA microarrays can give global transcriptional views of cellular responses to disease, development, nutrition, and other biological states. They can be used to elucidate biological networks, develop diagnostics, and identify genetic targets and molecular mechanisms. The technology is widely used and can be a valuable complement to more "disease-centric" focused arrays. For these reasons, Nestlé designed a custom canine Affymetrix microarray representing transcripts from multiple tissues for use in areas where a more focused microarray had not already been developed. Sufficient numbers of sequences representing messenger RNAs (mRNAs) or expressed sequence tags (ESTs) is integral for the design of a global microarray chip. This chip was designed using public domain sequences (GenBank) and sequences from a proprietary canine EST database. In order to enrich the chip with annotated transcripts, both of these sequence sets were BLASTed against the nonredundant protein database. The sequences on the microarray were isolated from more than 48 different tissues. The final compliment of sequences had sequences unique to GenBank (3160), unique to the proprietary EST database (17,620), and present in both sources (1996). In comparison with human sequences (RefSeq), 74% of the canine sequences matched a human sequence.

Role of nerve growth factor in the trinitrobenzene sulfonic acid-induced colonic hypersensitivity

The majority of patients with digestive disorders display visceral pain. In these troubles, visceral pain threshold is decreased, demonstrating visceral hypersensitivity. There is growing evidence that nerve growth factor (NGF) may function as a mediator of persistent pain states. This hypothesis was tested in a model of colonic hypersensitivity measured by isobaric distension in conscious rats. This study was designed to evaluate (1) the effect of exogenous NGF on colonic pain threshold, (2) the involvement of NGF in trinitrobenzene sulfonic acid (TNBS)-induced colonic hypersensitivity, by testing an anti-NGF antibody, and (3) finally the involvement of sensory nerves on NGF and TNBS effects using rats treated neonatally with capsaicin. Intra-peritoneal injection of NGF (0.1-100 ng/rat) decreased in a dose-related manner colonic pain threshold in naive rats. This effect was reversed by anti-NGF antibody (1/2000; 2 ml/kg). TNBS-induced colonic hypersensitivity was also reversed by anti-NGF antibody (1/2000; 2 ml/kg): 37.7 +/- 1.7 and 17.6 +/- 0.7 mmHg (p<0.01) for anti-NGF antibody- and vehicle-treated group, respectively. Neonatal capsaicin pre-treatment inhibited NGF- and TNBS-induced decrease in colonic pain threshold: 49.4 +/- 5.3 versus 22.3 +/- 1.6 mmHg (p<0.01) for capsaicin versus vehicle in NGF-treated rats and 39.6 +/- 3.3 versus 18.0 +/- 1.0 mm Hg (p<0.001) for capsaicin versus vehicle in TNBS-treated rats. These data suggest that the action of NGF on sensory neurons contributes to the development of visceral hypersensitivity and that anti-NGF strategy may be of some therapeutic benefits in digestive sensory disorders.

Role of nerve growth factor in the trinitrobenzene sulfonic acid-induced colonic hypersensitivity

The majority of patients with digestive disorders display visceral pain. In these troubles, visceral pain threshold is decreased, demonstrating visceral hypersensitivity. There is growing evidence that nerve growth factor (NGF) may function as a mediator of persistent pain states. This hypothesis was tested in a model of colonic hypersensitivity measured by isobaric distension in conscious rats. This study was designed to evaluate (1) the effect of exogenous NGF on colonic pain threshold, (2) the involvement of NGF in trinitrobenzene sulfonic acid (TNBS)-induced colonic hypersensitivity, by testing an anti-NGF antibody, and (3) finally the involvement of sensory nerves on NGF and TNBS effects using rats treated neonatally with capsaicin. Intra-peritoneal injection of NGF (0.1-100 ng/rat) decreased in a dose-related manner colonic pain threshold in naive rats. This effect was reversed by anti-NGF antibody (1/2000; 2 ml/kg). TNBS-induced colonic hypersensitivity was also reversed by anti-NGF antibody (1/2000; 2 ml/kg): 37.7 +/- 1.7 and 17.6 +/- 0.7 mmHg (p<0.01) for anti-NGF antibody- and vehicle-treated group, respectively. Neonatal capsaicin pre-treatment inhibited NGF- and TNBS-induced decrease in colonic pain threshold: 49.4 +/- 5.3 versus 22.3 +/- 1.6 mmHg (p<0.01) for capsaicin versus vehicle in NGF-treated rats and 39.6 +/- 3.3 versus 18.0 +/- 1.0 mm Hg (p<0.001) for capsaicin versus vehicle in TNBS-treated rats. These data suggest that the action of NGF on sensory neurons contributes to the development of visceral hypersensitivity and that anti-NGF strategy may be of some therapeutic benefits in digestive sensory disorders.

Pregabalin (CI-1008) inhibits the trinitrobenzene sulfonic acid-induced chronic colonic allodynia in the rat

In human, digestive disorders are often associated with visceral pain. In these pathologies, visceral pain threshold is decreased indicating a visceral hypersensitivity. Pregabalin [CI-1008; S-(+)-3-isobutylgaba] presents antihyperalgesic actions in inflammatory somatic pain models. This study was designed to evaluate 1) the effect of injection of TNBS into the colon on visceral pain threshold, and 2) the antihyperalgesic effect of pregabalin on TNBS-induced chronic colonic allodynia. A significant decrease in the colonic pain threshold was observed in trinitrobenzene sulfonic acid (TNBS)-treated animals (17.8 +/- 1.27 versus 43.4 +/- 1.98 mm Hg). Pregabalin (30-200 mg/kg s.c.) and morphine (0.1-1 mg/kg s.c.) showed a dose-related inhibition of TNBS-induced colonic allodynia. Pregabalin did not inhibit the colonic inflammatory effect of TNBS. In normal conditions (control animals), morphine (0.3 mg/kg s.c.) significantly increased the colonic pain threshold, whereas pregabalin (200 mg/kg s.c.) did not modify the colonic pain threshold. Pregabalin suppressed the TNBS-induced colonic allodynia but did not modify the colonic threshold in normal conditions. The ability of pregabalin to block the chronic colonic allodynia indicates that it is effective in abnormal colonic hypersensitivity, suggesting a possible effect in chronic pain in irritable bowel syndrome.

Fibroblast growth factor-18 is a trophic factor for mature chondrocytes and their progenitors

OBJECTIVE

The aim of this study was to examine the effects of recombinant human Fgf18 on chondrocyte proliferation and matrix production in vivo and in vitro. In addition, the expressions of Fgf18 and Fgf receptors (Fgfr) in adult human articular cartilage were examined.

METHODS

Adenovirus-mediated transfer of Fgf18 into murine pinnae and addition of FGF18 to primary cultures of adult articular chondrocytes were used to assess the effects of FGF18 on chondrocytes. In situ hybridization was used to examine the expression of Fgf18 and Fgfr s in adult human articular cartilage.

RESULTS

Expression of Fgf18 by adenovirus-mediated gene transfer in murine pinnae resulted in a significant increase in chondrocyte number. Chondrocytes were identified by staining with toluidine blue and a monoclonal antibody directed against type II collagen. Fgf18, Fgfr 2-(IIIc), Fgfr 3-(IIIc), and Fgfr 4 mRNAs were detected within these cells by in situ hybridization. The nuclei of the chondrocytes stained with antibodies to PCNA and FGF receptor (FGFR) 2. Addition of FGF18 to the culture media of primary articular chondrocytes increased the proliferation of these cells and increased their production of extracellular matrix. To assess the receptor selectivity of FGF18, BaF3 cells stably expressing the genes for the major splice variants of Fgfr1-3 were used. Proliferation of cells expressing Fgfr 3-(IIIc) or Fgfr 2-(IIIc) was increased by incubation with FGF18. Using FGFR-Fc fusion proteins and BaF3 cells expressing Fgfr 3-(IIIc), only FGFR 3-(IIIc)-Fc, FGFR 2-(IIIc)-Fc or FGFR 4-Fc reduced FGF18-mediated cell proliferation. Expression of Fgf18, Fgfr 3-(IIIc) and Fgfr 2-(IIIc) mRNAs was localized to chondrocytes of human articular cartilage by in situ hybridization.

CONCLUSION

These data demonstrate that Fgf18 can act as a trophic factor for elastic chondrocytes and their progenitors in vivo and articular chondrocytes cultured in vitro. Expression of Fgf18 and the genes for two of its receptors in chondrocytes suggests that Fgf18 may play an autocrine role in the biology of normal articular cartilage.

Steady-state end-tidal alveolar dead space fraction and D-dimer: bedside tests to exclude pulmonary embolism

STUDY OBJECTIVE

Less than 35% of patients suspected of having pulmonary embolism (PE) actually have PE. Safe bedside methods to exclude PE could save health-care resources and improve access to diagnostic testing for suspected PE. In patients with suspected PE, we sought to determine the sensitivity, specificity, and negative predictive value of (1) a steady-state end-tidal alveolar dead space fraction (AVDSf) of < 0.15, (2) a negative D-dimer result, and (3) the combination of a steady-state end-tidal AVDSf of < 0.15 and a negative D-dimer result.

STUDY DESIGN

Prospective cohort study.

SETTING

Tertiary-care center in Ottawa, Ontario, Canada.

PATIENTS

Consecutive inpatients, outpatients, and emergency department patients with suspected PE referred to the Departments of Nuclear Medicine or Radiology for investigation of suspected PE.

INTERVENTIONS AND MEASUREMENTS

All study patients had D-Dimer and alveolar dead space measurements prior to determining outcome (PE or no PE) with ventilation/perfusion scans and/or noninvasive leg vein imaging and/or pulmonary angiography.

RESULTS

Two hundred forty-six eligible and consenting patients underwent diagnostic imaging that excluded PE in 163 patients, diagnosed PE in 49 patients, and was indeterminant in 34 patients. A negative D-dimer result excluded PE with a sensitivity of 83.0% (95% confidence interval [CI], 69.2 to 92.4%), a negative predictive value of 91.2% (95% CI, 83.4 to 96.1%), and a specificity of 57.6%. A steady-state end-tidal AVDSf of < 0.15 excluded PE with a sensitivity of 79.5% (95% CI, 63.5 to 90.7%), a negative predictive value of 90.7% (95% CI, 82.5 to 95.9%), and a specificity of 70.3%. The combination of a negative D-dimer result and a steady-state end-tidal AVDSf of < 0.15 excluded PE with a sensitivity of 97.8% (95% CI, 88.5 to 99.9%), a negative predictive value of 98.0% (95% CI, 89.4 to 99.9%), and a specificity of 38.0%.

CONCLUSION

This simple combination of bedside tests may safely rule out PE without further diagnostic testing in large numbers of patients with suspected PE.

Monitoring gastrointestinal intraluminal PCO2: problems with airflow methods

Gastrointestinal intraluminal PCO2 (PiCO2) information is used to assess the adequacy of trauma patient resuscitation and to assist in choosing resuscitative interventions. Therefore, determining the limitations and potential caveats of different PiCO2 monitoring systems is clinically important. This study compared two PCO2 monitoring systems. The airflow device adds and then removes air samples to quantitate PCO2, whereas the fiber-optic device does not.

METHODS

Airflow (TRIP Tonometer/Tonocap) and fiber-optic (Neotrend) systems were used. In vitro they were compared with each other and to two end-tidal CO2 monitors measuring the PCO2 of humidified air containing 5% and then 10% CO2. In vivo the two systems' catheters were surgically juxtaposed in 15 dogs' stomachs; paired PiCO2 readings were taken throughout hemorrhage and resuscitation.

RESULTS

In vitro, paired PCO2 values from the airflow and fiber-optic devices correlated with each other (r = 0.99) and with end-tidal values (r = 0.99 with airflow, r = 0.95 with fiber-optic). In vivo, paired values differed significantly (P < 0.0001), correlating poorly for two devices simultaneously measuring the same variable (r = 0.61). Fiber-optic PiCO2 values were higher than airflow values (mmHg +/- SEM): 69.3 +/- 4.8 vs. 61.3 +/- 5.6 at the start of hemorrhage, 141.3 +/- 12.9 vs. 87.7 +/- 7.9 by end of hemorrhage, and 104.3 +/- 9.6 vs. 82.8 +/- 7.0 by end of resuscitation for fiber-optic and airflow, respectively.

CONCLUSIONS

Despite agreement in vitro, airflow methods can influence PiCO2 values obtained in vivo. Passive sensing methods used to monitor PiCO2, such as fiber-optic methods, are preferable because they neither deliver O2 to, nor remove CO2 from the local microenvironment.

Diagnostic value of arterial blood gas measurement in suspected pulmonary embolism

Pulmonary embolism (PE) is a common and lethal yet treatable condition. Several authors have reported on the diagnostic value of combinations of arterial blood gas (ABG) and other clinical data (i. e., prediction rules), and have claimed that these combinations can be safely used to exclude PE. The purpose of this investigation was to evaluate the diagnostic value of ABG measurement and to attempt to validate the ABG prediction rules published by these various authors for the assessment of patients with suspected PE. Two hundred ninety-three consecutive patients referred for imaging to investigate suspected PE were approached to participate in the investigation. ABG and other clinical data were obtained from consenting and eligible patients before an outcome classification (PE versus non-PE) was performed. None of the ABG data or prediction rules had sufficient negative predictive value, specificity, or likelihood ratios to be useful in the management of patients with suspected PE. We conclude that ABG data alone or in combination with other clinical data are not useful in the assessment of suspected PE.

Diagnostic value of the electrocardiogram in suspected pulmonary embolism

The electrocardiogram is shown to be of limited diagnostic value for determining pulmonary embolism in a prospective cohort study of unselected patients with suspected pulmonary embolism.