Hypoxaemia during induction of anaesthesia—an audit of children who underwent general anaesthesia for routine elective surgery

Arterial oxygen saturation was measured using pulse oximetry during induction of anaesthesia in 108 children aged 10 days--14 years. No restriction was placed on the method of induction. Oxygen saturation decreased to less than 90% in 29 children (26.8%) and less than 80% in seven children (6.4%). There was a significantly increased incidence of desaturation (to less than 90%) in children under one year of age, in those who had no premedication, in those who received only atropine as a premidicant and in children who were anxious or crying before intravenous induction. Oxygen saturation did not decrease below 90% in any child who received inhalational induction.     

Inflammatory bowel disease: A survey of the epidemiology in Asia

Inflammatory bowel disease (IBD) has long been considered a disease that affects predominantly a Western population. The incidence and prevalence rates from Asian populations are much lower in comparison. More recent data, however, have shown significantly higher rates in Asians and time trend studies have shown an increase in the incidence of ulcerative colitis (UC) and a similar but lower rise in Crohn's disease (CD). The epidemiological changes that are taking place mirror that of the Western experience seen 50 years previously and seem to occur in parallel with the rapid socioeconomic development taking place in Asia. It appears that certain racial groups are more prone than others to develop IBD. For instance, Indians in South‐East Asia have higher rates compared to Chinese and Malays. While there is host genetic predisposition, environmental factor(s) may be responsible for this difference. Migrant studies of South Asians in the UK, where second‐generation immigrants have assumed incidence rates as high as the indigenous whites and Asian Jews who develop high incidence rates comparable to Jews from Europe or North America in Israel point to the role of environmental factors. It is unclear which specific factors are responsible. Studies have suggested a change in diet to a more Westernized one may underlie this epidemiological change in the Asian population. It is likely that there are racial groups amongst Asians who are more susceptible to IBD and who will demonstrate a higher frequency of IBD when exposed to putative environmental factors.     

Heart rate reduces when stroke patients are touched . . . And??

McFadden KL, Hernández TD. Cardiovascular benefits of acupressure (Jin Shin) following stroke. Complement Ther Med 2010; 18: 42–8.     

Fast reconstructed radiographs from octree-compressed volumetric data

Purpose

Simulated 2D X-ray images called digitally reconstructed radiographs (DRRs) have important applications within medical image registration frameworks where they are compared with reference X-rays or used in implementations of digital tomosynthesis (DTS). However, rendering DRRs from a CT volume is computationally demanding and relatively slow using the conventional ray-casting algorithm. Image-guided radiation therapy systems using DTS to verify target location require a large number DRRs to be precomputed since there is insufficient time within the automatic image registration procedure to generate DRRs and search for an optimal pose.

Method

DRRs were rendered from octree-compressed CT data. Previous work showed that octree-compressed volumes rendered by conventional ray casting deliver a registration with acceptable clinical accuracy, but efficiently rendering the irregular grid of an octree data structure is a challenge for conventional ray casting. We address this by using vertex and fragment shaders of modern graphics processing units (GPUs) to directly project internal spaces of the octree, represented by textured particle sprites, onto the view plane. The texture is procedurally generated and depends on the CT pose.

Results

The performance of this new algorithm was found to be 4 times faster than that of a ray-casting algorithm implemented using NVIDIA?Compute Unified Device Architecture (CUDA?) on an equivalent GPU (~95 % octree compression). Rendering artifacts are apparent (consistent with other splatting algorithm), but image quality tends to improve with compression and fewer particles are needed. A peak signal-to-noise ratio analysis confirmed that the images rendered from compressed volumes were of marginally better quality to those rendered using Gaussian footprints.

Conclusions

Using octree-encoded DRRs within a 2D/3D registration framework indicated the approach may be useful in accelerating automatic image registration.     

Arterial “inflammaging” drives vascular calcification in children on dialysis

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Short tandem repeat (STR) haplotypes in HLA: an integrated 50-kb STR/linkage disequilibrium/gene map between the RING3 and HLA-B genes and identification of STR haplotype diversification in the class III region

We present a dense STR/linkage disequilibrium(LD)/gene map between the RING3 and HLA-B loci, reference allelic sizes on the most prevalent HLA haplotypes and their allelic frequencies in pedigree founders. This resource will facilitate LD, evolution and gene mapping studies, including comparisons of HLA and STR haplotypes and identification of HLA recombinants. The map was constructed by testing novel and previously reported STRs using a panel of 885 individuals in 211 families and 60 DNA samples from cell lines and bone marrow donors homozygous in the HLA-A, -B and -DR loci selected from over 15 000 entries into the registry of Swedish bone marrow donors. We have also analysed the variability of STR alleles/haplotypes on the most prevalent HLA haplotypes to identify STRs useful for fine mapping of disease genes in the region previously implicated in susceptibility to many disorders. The analysis of 40 HLA-A*01, B*0801, DRB1*03011, DQB1*0201 haplotypes in homozygous donors showed a surprising stability in 23 STRs between the class II recombination hot spot and HLA-B, with the average of 1.9% (16/838) variant alleles. However, 40% variant alleles were found at the D6S2670 locus in intron 19 of the tenascin-X gene both in the families and homozygous donors. The nucleotide sequence analysis of this STR showed a complex polymorphism consisting of tetra- (CTTT)(8-18) and penta-nucleotide (CTTTT)(1-2) repeats, separated by an intervening non-polymorphic sequence of 42 bp. The HLA-A1, B*0801, DRB1*03011, DQB1*0201 haplotypes had five (CTTT)(14-18)/(CTTTT)(2) variants with a predominant (CTTT)(16) allele, implicating the tetranucleotide component as the source of this ancestral haplotype diversification, which may be due to the location of D6S2670 in the region of the highest GC content in the human MHC.