Ground-state phase structure of the spin-1/2 anisotropic planar pyrochlore.

We study the zero-temperature ground-state (GS) properties of the spin-1/2 anisotropic planar pyrochlore, using the coupled cluster method (CCM) implemented to high orders of approximation. The system comprises a J 1-J 2 model on the checkerboard lattice, with isotropic Heisenberg interactions of strength J 1 between all nearest-neighbour pairs of spins on the square lattice, and of strength J 2 between half of the next-nearest-neighbour pairs (in the checkerboard pattern). We calculate results for the GS energy and average local GS on-site magnetization, using various antiferromagnetic classical ground states as CCM model states.

Safety and immunogenicity of RV3-BB human neonatal rotavirus vaccine administered at birth or in infancy: a randomised, double-blind, placebo-controlled trial.

Background: Despite the success of rotavirus vaccines, suboptimal vaccine efficacy in regions with a high burden of disease continues to present a challenge to worldwide implementation. A birth dose strategy with a vaccine developed from an asymptomatic neonatal rotavirus strain has the potential to address this challenge and provide protection from severe rotavirus disease from birth.

Methods: This phase 2a randomised, double-blind, three-arm, placebo-controlled safety and immunogenicity trial was undertaken at a single centre in New Zealand between Jan 13, 2012, and April 17, 2014.

Australian Rotavirus Surveillance Program annual report, 2012.

This report from the Australian Rotavirus Surveillance Program, together with collaborating laboratories Australia-wide, describes the rotavirus genotypes responsible for the hospitalisation of children with acute gastroenteritis during the period 1 January to 31 December 2012. During the survey period, 1,300 faecal samples were referred to the centre for rotavirus G and P genotype analysis, and of these 748 were confirmed as rotavirus positive. A total of 491 specimens were collected from children under 5 years of age, while 257 were from older children and adults.

Valence-bond crystalline order in the s = 1/2 J1-J2 model on the honeycomb lattice.

Using the coupled cluster method we study the phase diagram of the spin-1/2 Heisenberg antiferromagnet on a honeycomb lattice with nearest-neighbour exchange coupling J1 > 0 and frustrating next-nearest-neighbour coupling J2 ≡ xJ1 > 0. In the range 0 < x < 1 we find four phases exhibiting respectively Néel, 6-spin plaquette, staggered dimer and Néel-II orderings, with quantum critical points at xc1 ≈ 0.207(3), xc2 ≈ 0.

Bacteriophages in gut samples from pediatric Crohn's disease patients: metagenomic analysis using 454 pyrosequencing.

Background: The role of bacteriophage in Crohn's disease (CD) is unknown. This study investigated the abundance of phages in ileal and colonic samples from pediatric CD patients and controls.

Methods: Ileal and colonic biopsies from 6 CD patients, gut wash samples from 3 CD patients, and ileal biopsies from 6 noninflammatory bowel disease patients (controls) were analyzed for the presence of bacteriophage using 454 high-throughput pyrosequencing.

Phase I trial of RV3-BB rotavirus vaccine: a human neonatal rotavirus vaccine.

Introduction: RV3 is a human neonatal rotavirus strain (G3P[6]) that has been associated with asymptomatic neonatal infection and replicates well in the infant gut. RV3-BB rotavirus vaccine has been developed as a rotavirus vaccine candidate for administration at birth.

Methods: A single-centre, double-blind, randomised placebo-controlled Phase I study evaluated the safety and tolerability of a single oral dose of the second generation RV3-BB rotavirus vaccine (8.

Australian Rotavirus Surveillance Program annual report, 2010/11.

The Australian Rotavirus Surveillance Program together with collaborating laboratories Australia-wide conducts a laboratory based rotavirus surveillance program. This report describes the genotypes of rotavirus strains responsible for the hospitalisation of children with acute gastroenteritis during 1 July 2010 to 30 June 2011. This report represents the fourth year of surveillance following introduction of rotavirus vaccines into the National Immunisation Program.

Identification of strains of RotaTeq rotavirus vaccine in infants with gastroenteritis following routine vaccination.

Background: RotaTeq vaccine was introduced into the Australian National Immunisation Program in 2007. This study identified and characterised rotavirus strains excreted by infants who presented with symptoms of gastroenteritis following recent RotaTeq vaccination.

Methods: Fecal samples (N = 61) from children who developed gastroenteritis following recent RotaTeq vaccination were forwarded to the Australian Rotavirus Surveillance Program (ARSP).

The frustrated Heisenberg antiferromagnet on the honeycomb lattice: J1-J2 model.

We study the ground-state phase diagram of the frustrated spin-[Formula: see text] antiferromagnet with J(2) = xJ(1) > 0 (J(1) > 0) on the honeycomb lattice, using the coupled-cluster method. We present results for the ground-state energy, magnetic order parameter and plaquette valence-bond crystal (PVBC) susceptibility. We find a paramagnetic PVBC phase for x(c(1)) < x < x(c(2)), where x(c(1)) ≈ 0.

Expression profile of genes involved in pathogenesis of pediatric Crohn's disease.

Background And Aim: Expression profiling of genes specific to pediatric Crohn's Disease (CD) patients was performed to elucidate the molecular mechanisms underlying disease cause and pathogenesis at disease onset.

Methods: We used suppressive subtractive hybridization (SSH) and differential screening analysis to profile the mRNA expression patterns of children with CD and age- and sex-matched controls without inflammatory bowel disease (IBD).

Results: Sequence analysis of 1000 clones enriched by SSH identified 75 functionally annotated human genes, represented by 430 clones.

Australian Rotavirus Surveillance Program: annual report, 2009/2010.

The Australian Rotavirus Surveillance Program together with 15 collaborating laboratories Australia-wide conducts a laboratory based rotavirus surveillance program. This report describes the genotypes of rotavirus strains responsible for the hospitalisation of children with acute gastroenteritis during the period 1 July 2009 to 30 June 2010, the 3rd year of surveillance following introduction of rotavirus vaccines into the National Immunisation Program. Seven hundred and seventy-eight faecal samples were referred to the centre for G and P genotype analysis using hemi-nested multiplex reverse transcription-polymerase chain reaction.

Distribution of rotavirus genotypes after introduction of rotavirus vaccines, Rotarix® and RotaTeq®, into the National Immunization Program of Australia.

Background: Rotavirus vaccines, RotaTeq and Rotarix, were introduced into the Australian National Immunization Program on July 1, 2007. The simultaneous introduction in different Australian states and territories provides a unique opportunity to compare the affect of each vaccine on the types of circulating rotavirus strains. This report describes the rotavirus genotypes responsible for the hospitalization of children during the first 2-year period after vaccine introduction.

Maternal antibodies to rotavirus: could they interfere with live rotavirus vaccines in developing countries?

Introduction: Past experience with live oral vaccines including licensed rotavirus vaccines demonstrates a trend towards reduced vaccine efficacy in developing countries compared with developed countries. The reasons behind this disparity are not well understood. Transplacental transfer of maternal antibodies and breast milk ingestion may attenuate vaccine responses in infants in developing countries where rotavirus infections are endemic, and maternal antibody levels are high.

Interaction of Crohn's disease susceptibility genes in an Australian paediatric cohort.

Genetic susceptibility is an important contributor to the pathogenesis of Crohn's disease (CD). We investigated multiple CD susceptibility genes in an Australian paediatric onset CD cohort. Newly diagnosed paediatric onset CD patients (n = 72) and controls (n = 98) were genotyped for 34 single nucleotide polymorphisms (SNPs) in 18 genetic loci.

Molecular characterization and epidemiology of rotavirus isolates obtained from children with diarrhoea in Malaysia.

This retrospective study examined the G/P type of rotavirus in RNA samples that have previously been e-typed by RNA-PAGE in 1996. The results were then compared to 2007 samples to ascertain the extent of changes that may have occurred in this 11-years time interval. The G and P genotypes were determined by hemi-nested PCR and further analysed by phylogenetic study.

Australian Rotavirus Surveillance Program annual report, 2008/2009.

The Australian Rotavirus Surveillance Program together with collaborating laboratories Australia-wide, conducts a laboratory based rotavirus surveillance program. This report describes the genotypes of rotavirus strains responsible for the hospitalisation of children with acute gastroenteritis during the period 1 July 2008 to 30 June 2009, the second year of surveillance following introduction of rotavirus vaccine into the National Immunisation Program. Five hundred and ninety-two faecal samples from across Australia were examined for G and P genotype using hemi-nested multiplex reverse transcription-polymerase chain reaction assays.

Novel Burkholderiales 23S rRNA genes identified in ileal biopsy samples from children: preliminary evidence that a subtype is associated with perianal Crohn's disease.

A novel family of Burkholderiales bacteria was identified in ileal biopsy specimens from children presenting with symptoms of inflammatory bowel disease. A molecular subtyping approach based on sequencing of a variable region of the bacteria's 23S rRNA genes identified three variants. Pilot analysis identified one variant to be significantly associated with perianal Crohn's disease.

Circulating human group A rotavirus genotypes in Malaysia.

This study examined the temporal distribution of rotavirus genotypes in Malaysia. Rotaviruses from children with diarrhea admitted to hospitals in 1996 (n = 93) and 2007 (n = 12) in two different regions of Peninsular (West) Malaysia were analyzed for their G and P genotypes using a hemi-nested RT-PCR assay. In the 2007 samples, the dominant strain was G9P[8].

Rotavirus strain surveillance--an Australian perspective of strains causing disease in hospitalised children from 1997 to 2007.

This study documents rotavirus strains causing severe disease in Australian children during the pre-vaccine era. During the period 1997-2007, rotavirus strains from national multi-centre hospital-based surveillance in Australia were analysed for G and P types. G1P[8] was the dominant genotype identified during the 11-year study, with intermittent peaks associated with genotypes G2P[4], G3P[8] and G9P[8].

Mycobacterium avium subspecies paratuberculosis in children with early-onset Crohn's disease.

Background: Mycobacterium avium subspecies paratuberculosis (MAP) is the most enduring infectious candidate that may be associated with inflammatory bowel disease (IBD). It is possible that the inconsistencies in the prevalence studies of MAP in adults reflect clinical differences in adult patients studied, including duration of disease and treatment regimens, and also in lack of specificity of some of the assays used. The aim was to determine the presence of MAP in children with symptoms of Crohn's disease (CD) and ulcerative colitis (UC), using gut biopsy tissue and peripheral blood mononuclear cells (PBMC) collected at initial endoscopic examination prior to clinical treatment.

Australian Rotavirus Surveillance Program annual report, 2007/08.

The National Rotavirus Reference Centre together with collaborating laboratories Australia-wide conducts a laboratory based rotavirus surveillance program. This report describes the types of rotavirus strains responsible for the hospitalisation of children with acute gastroenteritis during the period 1 July 2007 to 30 June 2008, the first complete year of surveillance following introduction of rotavirus into the National Immunisation Program. Six hundred faecal samples from across Australia were examined using a combined approach of monoclonal antibody immunoassays and reverse transcription-polymerase chain reaction.

Identification and characterisation of Pseudomonas 16S ribosomal DNA from ileal biopsies of children with Crohn's disease.

Molecular analysis of bacterial 16S rRNA genes has made a significant contribution to the identification and characterisation of bacterial flora in the human gut. In particular, this methodology has helped characterise bacterial families implicated in the aetiology of inflammatory bowel disease (IBD). In this study we have used a genus specific bacterial 16S PCR to investigate the prevalence and diversity of Pseudomonas species derived from the ileum of children with Crohn's disease (CD), and from control children with non-inflammatory bowel disease (non-IBD) undergoing their initial endoscopic examination.