Bloodstream infection due to Acinetobacter spp: Epidemiology, risk factors and impact of multi-drug resistance
- Authors: Wareham, David , Bean, David , Khanna, Pooja , Hennessy, Enid , Krahe, Daniel , Ely, Andrew , Millar, Michael
- Date: 2008
- Type: Text , Journal article
- Relation: European Journal of Clinical Microbiology and Infectious Diseases Vol. 27, no. 7 (2008), p. 607-612
- Full Text: false
- Reviewed:
- Description: Acinetobacter spp. are increasingly reported as important causes of human infection. Many isolates exhibit multi-drug resistance, raising concerns over our ability to treat serious infections with these organisms. The impact of infection on clinical outcome as well as the importance of multi-drug resistance is poorly defined. A descriptive retrospective observational study was undertaken of all episodes of Acinetobacter bacteremia occurring in a UK tertiary care centre from 1998-2006. Demographics of infected patients, characteristics and antimicrobial susceptibility of infecting strains were recorded and the impact of antimicrobial therapy on all causes of 30-day mortality assessed. Three hundred ninety-nine episodes of Acinetobacter bacteremia were identified, with A. baumannii being the most frequently isolated species. Most episodes occurred in critical care and were associated with multidrug resistance, with carbapenem resistance rising from 0% in 1998 to 55% in 2006. Although bacteremia due to carbapenem-resistant Acinetobacter and a requirement for critical care were associated with a higher mortality, mortality was not reduced by the administration of appropriate empirical antimicrobial therapy. A prospective study is required to identify both the most effective intervention and those most likely to benefit from treatment.
- Description: C1
β-Adrenergic signaling regulates NR4A nuclear receptor and metabolic gene expression in multiple tissues
- Authors: Myers, Stephen , Eriksson, Natalie , Burow, Rachel , Wang, Mary Shu-Ching , Muscat, George
- Date: 2009
- Type: Text , Journal article
- Relation: Molecular and Cellular Endocrinology Vol. 309, no. 1-2 (2009), p. 101-108
- Full Text: false
- Reviewed:
- Description: The nuclear hormone receptor (NR) 4A subgroup of orphan nuclear receptors includes three members, Nur77 (NR4A1), Nurr1 (NR4A2) and Nor-1 (NR4A3). Previously we have identified the rapid and robust (in vitro and in vivo) induction of the NR4A subgroup following β-adrenergic stimulation in mouse skeletal muscle. This was concomitant with changes in the expression of genes involved in the regulation of nutrient metabolism. We have isolated mouse tissue of cardiovascular, endocrine and gastrointestinal origin at 1, 4, 8 and 24 h after a single intraperitoneal injection of the β-adrenergic agonist, isoprenaline. We similarly identified the significant induction (between 1 and 4 h) of the NR4A genes in many of these tissues. Moreover, we have utilized TaqMan ® Low Density Arrays to determine the β-adrenergic-sensitive metabolic gene expression in liver, white adipose and heart. In summary, cross-talk between β-adrenergic and NR4A signaling occurs in several tissues, and is accompanied by modulation of metabolic gene expression. © 2009 Elsevier Ireland Ltd. All rights reserved.
Increased production through parasite control : can ancient breeds of sheep teach us new lessons?
- Authors: Piedrafita, David , Raadsma, Herman , Gonzalez, Jorge , Meeusen, Els
- Date: 2010
- Type: Text , Journal article
- Relation: Trends in Parasitology Vol. 26, no. 12 (2010), p. 568-573
- Full Text: false
- Reviewed:
- Description: With a rising world population and economic development, the global demand for meat, milk and other animal products is increasing dramatically. Controlling parasitic diseases in livestock, in particular helminth infections, could rapidly improve productivity and resource utilization. There is a growing interest in indigenous ruminant breeds because these animals have adapted to survive with minimal maintenance in the presence of high exposure to parasite infection. Recent findings on the mechanisms of parasite resistance in indigenous breeds are discussed, and the possibility that such studies may lead to new insight into the immunity and control of parasites proposed. These findings have important implications for the preservation of poorly characterized local indigenous breeds.
PTP1B regulates Eph receptor function and trafficking
- Authors: Nievergall, Eva , Janes, Peter , Stegmayer, Caroline , Vail, Mary , Haj, Fawaz , Teng, Shyh , Neel, Benjamin , Bastiaens, Phillippe , Lackmann, Martin
- Date: 2010
- Type: Text , Journal article
- Relation: Journal of Cell Biology Vol. 191, no. 6 (2010), p. 1189-1203
- Full Text: false
- Reviewed:
- Description: Eph receptors orchestrate cell positioning during normal and oncogenic development. Their function is spatially and temporally controlled by protein tyrosine phosphatases (PTPs), but the underlying mechanisms are unclear and the identity of most regulatory PTPs are unknown. We demonstrate here that PTP1B governs signaling and biological activity of EphA3. Changes in PTP1B expression significantly affect duration and amplitude of EphA3 phosphorylation and biological function, whereas confocal fluorescence lifetime imaging microscopy (FLIM) reveals direct interactions between PTP1B and EphA3 before ligand-stimulated receptor internalization and, subsequently, on endosomes. Moreover, overexpression of wild-type (w/t) PTP1B and the [D-A] substrate–trapping mutant decelerate ephrin-induced EphA3 trafficking in a dose-dependent manner, which reveals its role in controlling EphA3 cell surface concentration. Furthermore, we provide evidence that in areas of Eph/ephrin-mediated cell–cell contacts, the EphA3–PTP1B interaction can occur directly at the plasma membrane. Our studies for the first time provide molecular, mechanistic, and functional insights into the role of PTP1B controlling Eph/ephrin-facilitated cellular interactions.
The effect of short-term creatine loading on active range of movement
- Authors: Sculthorpe, Nicholas , Grace, Fergal , Jones, Peter , Fletcher, Iain
- Date: 2010
- Type: Text , Journal article
- Relation: Applied Physiology, Nutrition, and Metabolism Vol. 35, no. 4 (2010), p. 507-511
- Full Text: false
- Reviewed:
- Description: During high-intensity exercise, intracellular creatine phosphate (PCr) is rapidly broken down to maintain adenosine triphosphate turnover. This has lead to the widespread use of creatine monohydrate as a nutritional ergogenic aid. However, the increase in intracellular PCr and the concomitant increase in intracellular water have not been investigated with regard to their effect on active range of movement (ROM). Forty male subjects (age, 24+/-3.2 years) underwent restricted randomization into 2 equal groups, either an intervention group (CS) or a control group (C). The CS group ingested 25 g.day(-1) of creatine monohydrate for 5 days, followed by 5 g.day(-1) for a further 3 days. Before (24 h before starting supplementation (PRE) and after (on the 8th day of supplementation (POST)) this loading phase, both groups underwent goniometry measurement of the shoulder, elbow, hip, and ankle. Data indicated significant reductions in active ROM in 3 movements: shoulder extension (57+/-11.3 degrees PRE vs. 48+/-11.2 degrees POST, p<0.01), shoulder abduction (183.4+/-6.8 degrees PRE vs. 180.3+/-5.1 degrees POST, p<0.05), and ankle dorsiflexion (14.2+/-4.7 degrees PRE vs. 12.1+/-6.4 degrees POST, p<0.01). There was also a significant increase in body mass for the CS group (83.6+/-6.2 kg vs. 85.2+/-6.3 kg, p<0.05). The results suggest that short-term supplementation with creatine monohydrate reduces the active ROM of shoulder extension and abduction and of ankle dorsiflexion. Although the mechanism for this is not fully understood, it may be related to the asymmetrical distribution of muscle mass around those joints.
A roadmap to generate renewable protein binders to the human proteome
- Authors: Colwill, Karen , Persson, Helena , Jarvik, Nicholas , Wyrzucki, Arkadiusz , Wojcik, John , Koide, Akiko , Kossiakoff, Anthony , Koide, Shohei , Sidhu, Sachdev , Dyson, Michael , Pershad, Kritika , Pavlovic, John , Karatt-Vellatt, Aneesh , Schofield, Darren , Kay, Brian , McCafferty, John , Mersmann, Michael , Meier, Doris , Mersmann, Jana , Helmsing, Saskia , Hust, Michael , Dubel, Stefan , Berkowicz, Susan , Freemantle, Alexia , Spiegel, Michael , Sawyer, Alan , Layton, Daniel , Nice, Edouard , Dai, Anna , Rocks, Oliver , Williton, Kelly , Fellouse, Frederic , Hersi, Kadija , Pawson, Tony , Nilsson, Peter , Sundberg, Marten , Sjoberg, Ronald , Sivertsson, Asa , Schwenk, Jochen , Takanen, Jenny , Hober, Sophia , Uhlen, Mathias , Dahlgren, Lars-Goran , Flores, Alex , Johansson, Ida , Weigelt, Johan , Crombet, Lissette , Loppnau, Peter , Kozieradzki, Ivona , Cossar, Doug , Arrowsmith, C. , Edwards, Aled , Graslund, Susanne
- Date: 2011
- Type: Text , Journal article
- Relation: Nature Methods Vol. 8, no. 7 (2011), p. 551-558
- Full Text: false
- Reviewed:
- Description: Despite the wealth of commercially available antibodies to human proteins, research is often hindered by their inconsistent validation, their poor performance and the inadequate coverage of the proteome. These issues could be addressed by systematic, genome-wide efforts to generate and validate renewable protein binders. We report a multicenter study to assess the potential of hybridoma and phage-display technologies in a coordinated large-scale antibody generation and validation effort. We produced over 1,000 antibodies targeting 20 SH2 domain proteins and evaluated them for potency and specificity by enzyme-linked immunosorbent assay (ELISA), protein microarray and surface plasmon resonance (SPR). We also tested selected antibodies in immunoprecipitation, immunoblotting and immunofluorescence assays. Our results show that high-affinity, high-specificity renewable antibodies generated by different technologies can be produced quickly and efficiently. We believe that this work serves as a foundation and template for future larger-scale studies to create renewable protein binders.
Association of genetic variation with systolic and diastolic blood pressure among African Americans: the Candidate Gene Association Resource study
- Authors: Fox, Ervin , Young, J. Hunter , Li, Yali , Dreisbach, Albert , Charchar, Fadi
- Date: 2011
- Type: Text , Journal article
- Relation: Human molecular genetics Vol. 20, no. 11 (June 2011), p. 2273
- Full Text:
- Reviewed:
- Description: The prevalence of hypertension in African Americans (AAs) is higher than in other US groups; yet, few have performed genome-wide association studies (GWASs) in AA. Among people of European descent, GWASs have identified genetic variants at 13 loci that are associated with blood pressure. It is unknown if these variants confer susceptibility in people of African ancestry. Here, we examined genome-wide and candidate gene associations with systolic blood pressure (SBP) and diastolic blood pressure (DBP) using the Candidate Gene Association Resource (CARe) consortium consisting of 8591 AAs. Genotypes included genome-wide single-nucleotide polymorphism (SNP) data utilizing the Affymetrix 6.0 array with imputation to 2.5 million HapMap SNPs and candidate gene SNP data utilizing a 50K cardiovascular gene-centric array (ITMAT-Broad-CARe [IBC] array). For Affymetrix data, the strongest signal for DBP was rs10474346 (P= 3.6 × 10−8) located near GPR98 and ARRDC3. For SBP, the strongest signal was rs2258119 in C21orf91 (P= 4.7 × 10−8). The top IBC association for SBP was rs2012318 (P= 6.4 × 10−6) near SLC25A42 and for DBP was rs2523586 (P= 1.3 × 10−6) near HLA-B. None of the top variants replicated in additional AA (n = 11 882) or European-American (n = 69 899) cohorts. We replicated previously reported European-American blood pressure SNPs in our AA samples (SH2B3, P= 0.009; TBX3-TBX5, P= 0.03; and CSK-ULK3, P= 0.0004). These genetic loci represent the best evidence of genetic influences on SBP and DBP in AAs to date. More broadly, this work supports that notion that blood pressure among AAs is a trait with genetic underpinnings but also with significant complexity.
Genome-wide association study identifies loci influencing concentrations of liver enzymes in plasma
- Authors: Chambers, John , Zhang, Weihua , Sehmi, Joban , Li, Xinzhong , Wass, Mark N , van der Harst, Pim , Holm, Hilma , Sanna, Serena , Kavousi, Maryam , Charchar, Fadi
- Date: 2011
- Type: Text , Journal article
- Relation: Nature genetics Vol. 43, no. 11 (2011), p. 1131-1138
- Full Text: false
- Reviewed:
- Description: Concentrations of liver enzymes in plasma are widely used as indicators of liver disease. We carried out a genome-wide association study in 61,089 individuals, identifying 42 loci associated with concentrations of liver enzymes in plasma, of which 32 are new associations (P = 10−8 to P = 10−190). We used functional genomic approaches including metabonomic profiling and gene expression analyses to identify probable candidate genes at these regions. We identified 69 candidate genes, including genes involved in biliary transport (ATP8B1 and ABCB11), glucose, carbohydrate and lipid metabolism (FADS1, FADS2, GCKR, JMJD1C, HNF1A, MLXIPL, PNPLA3, PPP1R3B, SLC2A2 and TRIB1), glycoprotein biosynthesis and cell surface glycobiology (ABO, ASGR1, FUT2, GPLD1 and ST3GAL4), inflammation and immunity (CD276, CDH6, GCKR, HNF1A, HPR, ITGA1, RORA and STAT4) and glutathione metabolism (GSTT1, GSTT2 and GGT), as well as several genes of uncertain or unknown function (including ABHD12, EFHD1, EFNA1, EPHA2, MICAL3 and ZNF827). Our results provide new insight into genetic mechanisms and pathways influencing markers of liver function. 137 authors
Multilocus sequence typing of Streptococcus pneumoniae by use of mass spectrometry
- Authors: Dunne, Eileen , Ong, Engkok , Moser, Ralf , Siba, Peter , Phuanukoonnon, Suparat , Greenhill, Andrew , Robins-Browne, Roy , Mulholland, Edward , Satzke, Catherine
- Date: 2011
- Type: Text , Journal article
- Relation: Journal of Clinical Microbiology Vol. 49, no. 11 (2011), p. 3756-3760
- Full Text: false
- Reviewed:
- Description: Multilocus sequence typing (MLST) is an important tool for the global surveillance of bacterial pathogens that is performed by comparing the sequences of designated housekeeping genes. We developed and tested a novel mass spectrometry-based method for MLST of Streptococcus pneumoniae. PCR amplicons were subjected to in vitro transcription and base-specific cleavage, followed by analysis of the resultant fragments by using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Comparison of the cleavage fragment peak patterns to a reference sequence set permitted automated identification of alleles. Validation experiments using 29 isolates of S. pneumoniae revealed that the results of MALDI-TOF MS MLST matched those obtained by traditional sequence-based MLST for 99% of alleles and that the MALDITOF MS method accurately identified two single-nucleotide variations. The MADLI-TOF MS method was then used for MLST analysis of 43 S. pneumoniae isolates from Papua New Guinean children. The majority of the isolates present in this population were not clonal and contained seven new alleles and 30 previously unreported sequence types.
Fetal sex affects expression of renin-angiotensin system components in term human decidua
- Authors: Wang, Yu , Pringle, Kirsty , Sykes, Shane , Marques, Francine , Morris, Brian , Zakar, Tamas , Lumbers, Eugenie
- Date: 2012
- Type: Text , Journal article
- Relation: Endocrinology Vol. 153, no. 1 (January 2012), p. 462-468
- Full Text: false
- Reviewed:
- Description: The maternal decidua expresses the genes of the renin-angiotensin system (RAS). Human decidua was collected at term either before labor (i.e. cesarean delivery) or after spontaneous labor. The mRNA for prorenin (REN), prorenin receptor (ATP6AP2), angiotensinogen (AGT), angiotensinconverting enzymes 1 and 2 (ACE1 and ACE2), angiotensin II type 1 receptor (AGTR1), and angiotensin 1-7 receptor (MAS1) were measured by quantitative real-time RT-PCR. Decidual explants were cultured in duplicate for 24 and 48 h, and all RAS mRNA, and the secretion of prorenin, angiotensin II, and angiotensin 1-7 was measured using quantitative real-time RT-PCR, ELISA, and radioimmunoassay, respectively. In the decidua collected before labor, REN mRNA levels were higher if the fetus was female. In addition, REN, ATP6AP2, AGT, and MAS1 mRNA abundance was greater in decidual explants collected from women carrying a female fetus, as was prorenin protein. After 24 h, ACE1 mRNA was higher in the decidual explants from women with a male fetus, whereas after 48 h, both ACE1 and ACE2 mRNA was higher in decidual explants from women with a female fetus. Angiotensin II was present in all explants, but angiotensin 1-7 levels often registered below the lower limits of sensitivity for the assay. After labor, decidua, when compared with nonlaboring decidua, demonstrated lower REN expression when the fetus was female. Therefore, the maternal decidual RAS is regulated in a sex-specific manner, suggesting that it may function differently when the fetus is male than when it is female.
- Description: C1
Field vaccination of sheep with a larval-specific antigen of the gastrointestinal nematode, Haemonchus contortus, confers significant protection against an experimental challenge infection
- Authors: Piedrafita, David , De Veer, Michael , Lydall, Jayne , Kraska, Troy , Elhay, Martin , Meeusen, Els
- Date: 2012
- Type: Text , Journal article
- Relation: Vaccine Vol. 30, no. 50 (2012), p. 7199-7204
- Full Text: false
- Reviewed:
- Description: The availability of effective vaccines would add a valuable tool to the management of gastrointestinal nematode infections in livestock. While some experimental vaccines have shown protection in laboratory trials, few have been tested in the field. In the present study, eight month old sheep kept on pasture were treated with anthelmintic 8 weeks before vaccination with a larval surface antigen of the nematode parasite, Haemonchus contortus, under a commercially acceptable protocol, i.e. 2 immunizations using a commercial adjuvant; they were then given a controlled challenge infection 4 weeks later in indoor pens. Vaccination of sheep with 4 increasing doses of antigen resulted in significant reductions of 61% and 27% in cumulative faecal egg counts in the two highest dose groups, and a 69% reduction in worm burden in the highest dose group. Blood loss, as determined by packed cell volume, was also significantly reduced in the highest dose group of sheep. One outlier sheep showed an unusual increase in egg count without a concomitant increase in worm burden compared to the control sheep, indicating a vaccine-induced stress response. Antigen-specific serum antibody levels steadily increased in sheep while on pasture and decreased when transported to indoor pens. No difference in antibody levels could be detected between vaccinated and unvaccinated sheep, but all showed increased antibody levels compared to uninfected control sheep kept in indoors pens for 2–3 months, suggesting sheep were sensitized to the larval antigen either from low dose pasture contamination or cross reaction with pasture-related antigens. The results of these studies confirm the protective properties of the larval surface antigen and its protective effect when vaccinations are performed in the field.
Is there a role for rare variants in DRD4 gene in the susceptibility for ADHD Searching for an effect of allelic heterogeneity
- Authors: Tovo-Rodrigues, Luciana , Rohde, Luis , Roman, Tatiana , Schmitz, Marcelo , Polanczyk, Guilherme , Zeni, Cristian , Marques, Francine , Contini, Veronica , Grevet, Eugenio , Belmonte-De-Abreu, Paulo , Bau, Claiton , Hutz, Mara
- Date: 2012
- Type: Text , Journal article
- Relation: Molecular Psychiatry Vol. 17, no. 5 (May 2012), p. 520-526
- Full Text: false
- Reviewed:
- Description: Although several studies have demonstrated an association between the 7-repeat (7R) allele in the 48-bp variable number of tandem repeats (VNTRs) in the exon 3 at dopamine receptor D4 (DRD4) gene and attention-deficit/ hyperactivity disorder (ADHD), others failed to replicate this finding. In this study, a total of 786 individuals with ADHD were genotyped for DRD4 exon 3 VNTR. All 7R homozygous subjects were selected for VNTR re-sequencing. Subjects homozygous for the 4R allele were selected paired by age, ancestry and disorder subtypes in order to have a sample as homogeneous as possible with 7R/7R individuals. Using these criteria, 103 individuals (66 with ADHD and 37 control individuals) were further investigated. An excess of rare variants were observed in the 7R alleles of ADHD patient when compared with controls (P = 0.031). This difference was not observed in 4R allele. Furthermore, nucleotide changes that predict synonymous and non-synonymous substitutions were more common in the 7R sample (P = 0.008 for total substitutions and P = 0.043 for non-synonymous substitutions). In silico prediction of structural/functional alterations caused by these variants have also been observed. Our findings suggest that not only repeat length but also DNA sequence should be assessed to better understand the role of DRD4 exon 3 VNTR in ADHD genetic susceptibility.
- Description: C1
The NF-κB1 transcription factor prevents the intrathymic development of CD8 T cells with memory properties
- Authors: Gugasyan, Raffi , Horat, Elisha , Kinkel, Sarah , Ross, Fiona , Grigoriadis, George , Gray, Daniel , O'Keeffe, Meredith , Berzins, Stuart , Belz, Gabrielle , Grumont, Raelene , Banerjee, Ashish , Strasser, Andreas , Godfrey, Dale , Tsichlis, Phillip , Gerondakis, Steve
- Date: 2012
- Type: Text , Journal article
- Relation: EMBO Journal Vol. 31, no. 3 (2012), p. 692-706
- Full Text: false
- Reviewed:
- Description: The role of specific members of the NF-κB family of transcription factors in CD8 T-cell selection and development is largely unknown. Here, we show that mice lacking NF-κB1 develop a unique population of conventional CD8 single-positive (SP) thymocytes with memory T cell-like properties that populate peripheral immune organs. Development of this memory-like population is not due to PLZF + thymocytes and instead coincides with changes in CD8 T-cell selection. These include a reduction in the efficiency of negative selection and a dependence on MHC class Ia or Ib expressed by haematopoietic cells. These findings indicate that NF-κB1 regulates multiple events in the thymus that collectively inhibit the excess development of CD8 + thymocytes with memory cell characteristics. © 2012 European Molecular Biology Organization | All Rights Reserved.
Age-related differences revealed in australian fur seal arctocephalus pusillus doriferus gut microbiota
- Authors: Smith, Stuart , Chalker, Andrea , Dewar, Meagan , Arnould, John
- Date: 2013
- Type: Text , Journal article
- Relation: FEMS Microbiology Ecology Vol. 86, no. 2 (2013), p. 246-255
- Full Text: false
- Reviewed:
- Description: The gut microbiota of Australian fur seals (Arctocephalus pusillus doriferus) was examined at different age classes using fluorescent in situ hybridisation (FISH) and 16S rRNA gene pyrosequencing. The FISH results indicated that in the fur seal groups, the predominant phyla are Firmicutes (22.14-67.33%) followed by Bacteroidetes (3.11-15.45%) and then Actinobacteria (1.4-5.9%) consistent with other mammals. Phylum Proteobacteria had an initial abundance of 1.8% in the 2-month-old pups, but < 1% of bacterial numbers for the other fur seal age groups. Significant differences did occur in the abundance of Clostridia, Lactobacilli and Bifidobacteria between 2 months pups and 9 months pups and adult fur seals. Results from the 16S rRNA gene pyrosequencing supported the FISH data and identified significant differences in the composition of Firmicutes, Bacteroidetes, Actinobacteria, Proteobacteria, Verrucomicrobia and Fusobacteria at all ages. Class Clostridia in phylum Firmicutes dominates the microbiota of the 2 months and 9 months seal pups, whilst class Bacilli dominates the 6 months pups. In addition, a high level of dissimilarity was observed between all age classes. This study provides novel insight into the gut microbiota of Australian fur seals at different age classes. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.
Local immune responses of the Chinese water buffalo, Bubalus bubalis, against Schistosoma japonicum larvae: crucial insights for vaccine design
- Authors: McWilliam, Hamish , Piedrafita, David , Li, Yuesheng , Zheng, Mao , He, Yongkang , Yu, Xinling , McManus, Donald , Meeusen, Els
- Date: 2013
- Type: Text , Journal article
- Relation: PLoS Neglected Tropical Diseases. Vol.7, no.9(Art.No: e2460) (2013), p. 1-11
- Full Text:
- Reviewed:
- Description: Asian schistosomiasis is a zoonotic parasitic disease infecting up to a million people and threatening tens of millions more. Control of this disease is hindered by the animal reservoirs of the parasite, in particular the water buffalo (Bubalus bubalis), which is responsible for significant levels of human transmission. A transmission-blocking vaccine administered to buffaloes is a realistic option which would aid in the control of schistosomiasis. This will however require a better understanding of the immunobiology of schistosomiasis in naturally exposed buffaloes, particularly the immune response to migrating schistosome larvae, which are the likely targets of an anti-schistosome vaccine. To address this need we investigated the immune response at the major sites of larval migration, the skin and the lungs, in previously exposed and re-challenged water buffaloes. In the skin, a strong allergic-type inflammatory response occurred, characterised by leukocyte and eosinophil infiltration including the formation of granulocytic abscesses. Additionally at the local skin site, interleukin-5 transcript levels were elevated, while interleukin-10 levels decreased. In the skin-draining lymph node (LN) a predominant type-2 profile was seen in stimulated cells, while in contrast a type-1 profile was detected in the lung draining LN, and these responses occurred consecutively, reflecting the timing of parasite migration. The intense type-2 immune response at the site of cercarial penetration is significantly different to that seen in naive and permissive animal models such as mice, and suggests a possible mechanism for immunity. Preliminary data also suggest a reduced and delayed immune response occurred in buffaloes given high cercarial challenge doses compared with moderate infections, particularly in the skin. This study offers a deeper understanding into the immunobiology of schistosomiasis in a natural host, which may aid in the future design of more effective vaccines.
Effects of hypoxia and hypercapnia on human HRV and respiratory sinus arrhythmia
- Authors: Brown, Stephen , Barnes, Matthew , Mündel, Toby
- Date: 2014
- Type: Text , Journal article
- Relation: Acta Physiologica Hungarica Vol. 101, no. 3 (2014), p. 263-272
- Full Text: false
- Reviewed:
- Description: Hypercapnia increase minute ventilation (V'E) with little effect on heart rate (HR), whereas hypoxia may increase HR without affecting V'E. However, the effects of hypercania and hypoxia on both heart rate variability (HRV) and the clustering of the heart beats during spontaneous breathing (respiratory sinus arrhythmia -RSA) are not clear. "From abstract"
Interspecific variations in the faecal microbiota of Procellariiform seabirds
- Authors: Dewar, Meagan , Arnould, John , Krause, Lutz , Dann, Peter , Smith, Stuart
- Date: 2014
- Type: Text , Journal article
- Relation: FEMS Microbiology Ecology Vol. 89, no. 1 (2014), p. 47-55
- Full Text: false
- Reviewed:
- Description: Despite the enormous amount of data available on the importance of gut microbiota in vertebrates (especially mammals), there is no information available on the microbiota of seabirds. Procellariiformes are long-lived seabirds that consume a diet high in lipids and are characterised by their ability to produce and store large amount of stomach oils through the partial digestion of prey (with the exception of the Pelecanoididae). Examining the faecal microbiota of three Procellariiform species (short-tailed shearwater, common diving petrel and fairy prion) provided a unique opportunity to not only characterise the gastrointestinal (GI) microbial composition of seabirds but to also examine the influence of stomach oils on the microbial community. The results indicated that Procellariiform seabirds host a highly diverse community of faecal microorganisms, dominated by three phyla (Firmicutes, Proteobacteria and Bacteroidetes) and that each species has its own species-specific GI microbiota. In addition, significant differences were observed in the microbial communities of oil-producing and non-oil-producing seabirds. This study is the first whole-community examination and classification of the faecal microbiota of Procellariiform seabirds.
Acute whole body UVA irradiation combined with nitrate ingestion enhances time trial performance in trained cyclists
- Authors: Muggeridge, David , Sculthorpe, Nicholas , Grace, Fergal , Willis, Gareth , Thornhill, Laurence , Weller, Richard , James, Philip , Easton, Chris
- Date: 2015
- Type: Text , Journal article
- Relation: Nitric Oxide : Biology and Chemistry Vol. 48, no. (2015), p. 3-9
- Full Text:
- Reviewed:
- Description: Dietary nitrate supplementation has been shown to increase nitric oxide (NO) metabolites, reduce blood pressure (BP) and enhance exercise performance. Acute exposure to ultraviolet (UV)-A light also increases NO bioavailability and reduces BP. We conducted a randomized, counterbalanced placebo-controlled trial to determine the effects of UV-A light alone and in combination with nitrate on the responses to sub-maximal steady-state exercise and time trial (TT) performance. Nine cyclists (VO2max 53.1 +/- 4.4 ml/kg/min) completed five performance trials comprising 10 min submaximal steady-state cycling followed by a 16.1 km TT. Following a familiarization the final four trials were preceded, in random order, by either (1) Nitrate gels (NIT) + UV-A, (2) Placebo (PLA) + UV-A, (3) NIT + Sham light (SHAM) and (4) PLA + SHAM (control). The NIT gels (2 x 60 ml gels, ~8.1 mmol nitrate) or a low-nitrate PLA were ingested 2.5 h prior to the trial. The light exposure consisted of 20 J/cm(2) whole body irradiation with either UV-A or SHAM light. Plasma nitrite was measured pre- and post-irradiation and VO2 was measured continuously during steady-state exercise. Plasma nitrite was higher for NIT + SHAM (geometric mean (95% CI), 332 (292-377) nM; P = 0.029) and NIT + UV-A (456 (312-666) nM; P = 0.014) compared to PLA + SHAM (215 (167-277) nM). Differences between PLA + SHAM and PLA + UV-A (282 (248-356) nM) were small and non-significant. During steady-state exercise VO2 was reduced following NIT + UVA (P = 0.034) and tended to be lower in NIT + SHAM (P = 0.086) but not PLA + UV-A (P = 0.381) compared to PLA + SHAM. Performance in the TT was significantly faster following NIT + UV-A (mean +/- SD 1447 +/- 41 s P = 0.005; d = 0.47), but not PLA + UV-A (1450 +/- 40 s; d = 0.41) or NIT + SHAM (1455 +/- 47 s; d = 0.28) compared to PLA + SHAM (1469 +/- 52 s). These findings demonstrate that exposure to UV-A light alone does not alter the physiological responses to exercise or improve performance in a laboratory setting. A combination of UV-A and NIT, however, does improve cycling TT performance in this environment, which may be due to a larger increase in NO availability.
Changes in the leukocyte methylome and its effect on cardiovascular-related genes after exercise
- Authors: Denham, Joshua , O'Brien, Brendan , Marques, Francine , Charchar, Fadi
- Date: 2015
- Type: Text , Journal article
- Relation: Journal of Applied Physiology Vol. 118, no. 4 (2015), p. 475-488
- Relation: http://purl.org/au-research/grants/nhmrc/1009490
- Full Text: false
- Reviewed:
- Description: Physical exercise has proven cardiovascular benefits, yet there is no clear understanding of the related molecular mechanisms leading to this. Here we determined the beneficial epigenetic effects of exercise after sprint interval training, a form of exercise known to improve cardiometabolic health. We quantified genome-wide leukocyte DNA methylation of 12 healthy young (18-24 yr) men before and after 4 wk (thrice weekly) of sprint interval training using the 450K BeadChip (Illumina) and validated gene expression changes in an extra seven subjects. Exercise increased subjects' cardiorespiratory fitness and maximal running performance, and decreased low-density lipoprotein cholesterol concentration in conjunction with genome-wide DNA methylation changes. Notably, many CpG island and gene promoter regions were demethylated after exercise, indicating increased genome-wide transcriptional changes. Among genes with DNA methylation changes, epidermal growth factor (EGF), a ligand of the epidermal growth factor receptor known to be involved in cardiovascular disease, was demethylated and showed decreased mRNA expression. Additionally, we found that in microRNAs miR-21 and miR-210, gene DNA methylation was altered by exercise causing a cascade effect on the expression of the mature microRNA involved in cardiovascular function. Our findings demonstrate that exercise alters DNA methylation in circulating blood cells in microRNA and protein-coding genes associated with cardiovascular physiology. Copyright © 2015 the American Physiological Society
Distinctive phenotype identification for breast cancer genotypes among hereditary breast cancer mutated genes
- Authors: Hassan, Md Rafiul , ul Haq, Imran , Ramadan, Emad , Kamruzzaman, Joarder , Ahmed, Adel
- Date: 2015
- Type: Text , Journal article
- Relation: Current Bioinformatics Vol. 10, no. 1 (2015), p. 5-15
- Full Text: false
- Reviewed:
- Description: It is well known that the mutations in BRCA1 or BRCA2 gene can cause the hereditary breast cancer. However, it is a tedious and expensive task to identify the mutant genes that impact breast cancer due to the large number of genes and very small number of samples. Furthermore, the expressive energy of the subset of genes in comparison to that of one individual gene at a time is considered to have a profound influence in case of breast cancer. In this paper 7 tumors with BRCA1 mutation and 8 tumors with BRCA2 mutation have been used to identify the subset of discriminative genes. A combination of a non-parametric supervised and an unsupervised statistical method is introduced to analyze the gene expressions and the distinctive genes among the highly expressed genes are identified. The most important genes are filtered using the area under the curve (AUC) measure. These filtered genes are then used to build a hidden Markov model (HMM) to analyse their inter-relationship and identify the best subset among them. In addition, Protein-Protein interaction network is generated to analyse the pathways of the identified genes and their link with BRCA1 or BRCA2. Transcription Factors are identified and Gene Set Enrichment Analysis (GSEA) is calculated for the identified genes subset and the results are compared with the results mentioned in other cancer literature. Experimental results suggest that only 8 genes have been identified out of 3226 genes by the proposed hybrid method. Out of the 8 identified genes, 5 have been linked with breast cancer by other studies. Moreover, 7 genes have been associated with numerous diseases that may result in breast cancer. Furthermore, 8 transcription factors were identified that cover the identified genes and BRCA1 and BRCA2. Lastly, GSEA enrichment score of 0.52 is calculated for the identified genes and it is comparatively better considering the small subset of identified genes.