Linearity study of blood calcium test

BACKGROUND

The EP6-A protocol and Dr. Kroll's EP6-A extended methods are newly approved schemes for assessing linearity. Linearity surveys are used to evaluate the performances of clinical laboratories and improve the quality of tests.

METHODS

In accordance with the instruments used, the data of blood calcium were divided into four groups: Olympus (70 labs), Hitachi (57 labs), Beckman CX (17 labs), and Beckman LX (28 labs). Statistically significant linearity and nonlinearity were judged using polynomial regression analysis, as recommended by the Clinical and Laboratory Standards Institute EP6-A guideline. The imprecision of analytical data were analyzed and the extents of nonlinearity were determined using Dr. Kroll's EP6-A extended methods.

RESULTS

In samples analyzed using Olympus, Hitachi, Beckman CX, and Beckman LX instruments, the imprecision ranged from 0.05% - 11.92%, 0.16% - 10.39%, 0.42% - 2.73%, and 0.10% - 4.10%, respectively. The imprecision for two laboratories in the Olympus and Hitachi groups exceeded the acceptable limits, while the imprecision for the remaining laboratories were precise enough for a linear survey. The average deviations from linearity ranged from 0% - 2.74%, 0% - 3.92%, 0% - 2.25% and 0% - 3.73%, respectively. The linearity with statistical significance was 28.6%, 43.9%, 41.2%, and 3.6%, respectively. The linearity with clinical significance was 70.0%, 54.4%, 58.8%, and 96.4%, respectively. The percentages of laboratories whose blood calcium analyses met the linearity criteria were 98.6%, 98.3%, 100%, and 100%, respectively.

CONCLUSIONS

The majority of the laboratories involved in the linearity survey showed good capability for blood calcium testing.

Intrusion Detection using Continuous Time Bayesian Networks

Intrusion detection systems (IDSs) fall into two high-level categories: network-based systems (NIDS) that monitor network behaviors, and host-based systems (HIDS) that monitor system calls. In this work, we present a general technique for both systems. We use anomaly detection, which identifies patterns not conforming to a historic norm. In both types of systems, the rates of change vary dramatically over time (due to burstiness) and over components (due to service difference). To efficiently model such systems, we use continuous time Bayesian networks (CTBNs) and avoid specifying a fixed update interval common to discrete-time models. We build generative models from the normal training data, and abnormal behaviors are flagged based on their likelihood under this norm. For NIDS, we construct a hierarchical CTBN model for the network packet traces and use Rao-Blackwellized particle filtering to learn the parameters. We illustrate the power of our method through experiments on detecting real worms and identifying hosts on two publicly available network traces, the MAWI dataset and the LBNL dataset. For HIDS, we develop a novel learning method to deal with the finite resolution of system log file time stamps, without losing the benefits of our continuous time model. We demonstrate the method by detecting intrusions in the DARPA 1998 BSM dataset.

Lithium delivery enhances bone growth during midpalatal expansion

Lithium is an activator of β-catenin signaling, and β-catenin mediates bone acquisition in response to mechanical loading in the bone. We tested the hypothesis that lithium enhances new bone formation during midpalatal suture expansion. Forty-eight Wistar rats with or without suture expansion were gavage-fed daily with lithium chloride or sodium chloride. We labeled the rats with bromodeoxyuridine to evaluate the proliferation and differentiation of the osteoprogenitors. Lithium increased β-catenin expression and cell proliferation in expanding sutures. Initial delay in the differentiation of osteoprogenitors into mature osteoblasts by lithium treatment corresponded with expansion of pre-osteoblasts, which preceded the increase of new bone formation in the suture. These results suggested that β-catenin regulates proliferation of osteoprogenitors and maturation of osteoblasts during midpalatal suture expansion osteogenesis, and that lithium enhances bone regeneration by elevating β-catenin expression. Lithium treatment could be a pharmaceutical aid to improve the stability of orthodontic treatment like rapid palatal expansion.

Quantum dot/carbon nanotube/silicon double heterojunctions for multi-band room temperature infrared detection

We report on the observation of room temperature multi-band photocurrent response from a novel structure formed by interior loading of PbS quantum dots into carbon nanotubes grown on silicon. In addition to a mid infrared photoresponse band at ∼ 0.22 eV due to the carbon nanotubes and one band at 1.1 eV corresponding to silicon, two bands in the mid/near infrared at 0.63 and 0.82 eV, corresponding to the first and second exciton bands of the PbS quantum dots, are observed in photocurrents measured at room temperature, in uncooled operation. We have also observed a red shift of the 0.63 and 0.82 eV bands with cooling that reflects a behavior typical for PbS and supports the hypothesis that these photoresponse bands are due to absorption in the PbS quantum dots.

Influence of in ovo injection of disaccharides, glutamine and β-hydroxy-β-methylbutyrate on the development of small intestine in duck embryos and neonates

1. The objective of the present study was to examine the effect of in ovo injection of disaccharides (DS), disaccharides and glutamine (DS + Gln) or disaccharides and β-hydroxy-β-methylbutyrate (DS + HMB) at d 23 of incubation on the development of the small intestine. 2. In DS + Gln-injected ducks, the greatest relative small intestine mass and muscularis layer thickness among 4 treatments was observed from d 25 of incubation to 7 d of age. 3. Jejunal sucrase activity in DS-injected ducks was significantly greater than in controls at hatch and on d 7. 4. In DS + HMB-treated ducks, a tendency toward slightly higher jejunal DNA concentration was observed throughout the experiment. 5. Greater body weight was found in DS + Gln and DS + HMB treated ducks in the first two weeks. However, there was no significant difference in the market weight (35 d) of ducks among the 4 treatments. 6. The results of present study suggest that administering disaccharides and Gln, or disaccharides and HMB, to the duck embryos exerted a beneficial effect on the early development of small intestine and on growth performance.

Association of single-nucleotide polymorphisms in HLA class II/III region with knee osteoarthritis

OBJECTIVE

A genome-wide association study and a replication using Japanese, Spanish and Greek Caucasian populations have recently indicated two single-nucleotide polymorphisms (SNPs) (rs7775228 and rs10947262) associated with knee Osteoarthritis (OA) susceptibility. We have further evaluated the association in knee OA subjects from Han Chinese and Australian Caucasian origin.

METHODS

Two independent case-control association studies were performed using Han Chinese and Australian Caucasian populations. The two SNPs were genotyped in patients who had primary symptomatic knee OA with radiographic confirmation and/or received total knee replacement surgery as well as in matched controls. They were subjected to statistic analyses.

RESULTS

A total of 991 OA patients and 1536 controls were genotyped. No significant difference was detected in genotype or allele frequencies of the two SNPs between knee OA and control groups in the two populations (all P>0.05). The association was also negative even after stratification by sex, body mass index (BMI) and Kellgren/Lawrence scores. The significant heterogeneity was detected between Chinese and Japanese (both P<0.05). In the Caucasian samples, no significant heterogeneity was detected (both P>0.05). The result of meta-analysis showed significant association between knee OA and rs10947262 in total subjects [summary OR=1.26, 95%confidence intervals (CI)=1.07-1.27, P=3 × 10(-8)] and in Caucasian samples (summary OR=1.28, 95%CI=1.04-1.57, P=0.02).

CONCLUSION

We demonstrated no association between the two SNPs in human leukocyte antigen (HLA) class II/III region and knee OA in Han Chinese population. A significant association was detected between SNP rs10947262 and knee OA in Caucasian subjects. Further replication studies are required to identify the impact of controversial association.

Molecular, developmental, and evolutionary genetic studies highlight rapid evolution of genes and genetic systems

The 53rd annual conference of the Genetics Society of Canada was held at McMaster University in Hamilton, Ontario, from 17 to 20 June 2010. About 100 geneticists from across Canada and the US attended the meeting, with a total of 27 posters and 55 oral presentations. The presentations highlighted the power of genetics for understanding a variety of biological issues from sex and recombination to alcoholism and cancer, from DNA replication to antimicrobial resistance, horizontal gene transfer, foraging, and courtship. Large-scale genomic and transcriptomic comparisons were included in many presentations to demonstrate the impact of genomics in biomedical research. The combined molecular, developmental, and evolutionary genetic investigations presented at the meeting, especially those on model organisms, highlighted that genes and genetic systems can evolve very rapidly.

Adsorption of platinum(IV) and palladium(II) from aqueous solution by magnetic cross-linking chitosan nanoparticles modified with ethylenediamine

The adsorption characteristics of platinum(IV) and palladium(II) from aqueous solutions onto the ethylenediamine-modified magnetic chitosan nanoparticles (EMCN) have been investigated. The magnetic chitosan nanoparticles were prepared by adding the basic precipitant of NaOH solution into a W/O microemulsion system. The transmission electron microscope showed that the diameter of EMCN was from 15 to 40 nm. The adsorption experiments indicated that the maximum adsorption capacity occurred at around pH 2.0 for both Pt(IV) and Pd(II). Due to the small diameter and the high surface reactivity, the adsorption equilibrium of Pt(IV) and Pd(II) onto the EMCN reached very quickly. The maximum loading capacity of EMCN for Pt(IV) and Pd(II) was determined to be 171 and 138 mg/g, respectively. Sorption isotherms were determined both in single component with pure metal solutions and bicomponent systems with different Pd/Pt mass ratios. The results showed that the sorbents had a greater affinity for Pt(IV) than for Pd(II). The total sorption capacity was comparable to that of each metal individually, indicating that the metals compete for the same sorption sites. It was found that 0.4 M HNO(3)-1.0 M thiourea solution provided effectiveness of the desorption of Pt(IV) and Pd(II) from EMCN, while 5 M ammonia exhibited the highest selectivity for the tested metal ions.

A prospective comparative study of kyphoplasty using the Jack vertebral dilator and balloon kyphoplasty for the treatment of osteoporotic vertebral compression fractures

This study prospectively compared the efficacy of kyphoplasty using a Jack vertebral dilator and balloon kyphoplasty to treat osteoporotic compression fractures between T10 and L5. Between 2004 and 2009, two groups of 55 patients each underwent vertebral dilator kyphoplasty and balloon kyphoplasty, respectively. Pain, function, the Cobb angle, and the anterior and middle height of the vertebral body were assessed before and after operation. Leakage of bone cement was recorded. The post-operative change in the Cobb angle was significantly greater in the dilator kyphoplasty group than in the balloon kyphoplasty group (-9.51 degrees (sd 2.56) vs -7.78 degrees (sd 1.19), p < 0.001)). Leakage of cement was less in the dilator kyphoplasty group. No other significant differences were found in the two groups after operation, and both procedures gave equally satisfactory results in terms of all other variables assessed. No serious complications occurred in either group. These findings suggest that vertebral dilator kyphoplasty can facilitate better correction of kyphotic deformity and may ultimately be a safer procedure in reducing leakage of bone cement.

CCMG guidelines: prenatal and postnatal diagnostic testing for uniparental disomy

The aim of this statement is to provide clinicians, cytogeneticists and molecular geneticists of the Canadian College of Medical Geneticists (CCMG) a comprehensive review of the role of UPD in constitutional genetic diagnosis and to provide a guideline as to when investigation for UPD is recommended. Members of the CCMG Cytogenetics, Molecular Genetics, Clinical Practice, and Prenatal Diagnosis committees reviewed the relevant literature on uniparental disomy (UPD) in constitutional genetic diagnosis (May 2010). Guidelines were developed for UPD testing in Canada. The guidelines were circulated for comment to the CCMG members at large and following appropriate modification, approved by the CCMG Board of Directors (July 2010).

Structural features of the 5’ flanking region of the Yak (Bos grunniens) growth hormone receptor (GHR) gene (Brief Report)

Abstract. Yak (Bos grunniens) is a species of the Bovidae family living on the Qinghai-Tibetan Plateau and its adjacent territories at altitudes from 2 000–5 000 m (LUO et al. 2005, MA et al. 2009). As a multi-purpose domestic animal, yaks are indispensable to the local animal husbandry development because it can provide life necessities such as meat, milk, fur, velour manufacturing, transportation and manure for fuel to the local herdsmen. There are twelve yak populations numbered around 13.3 million in China and the Bazhou yak is one of Chinese yak populations (WIENER et al. 2003). The Growth Hormone Receptor (GHR) gene was identified as a candidate gene affecting key quantitative traits, like growth, milk yield and composition in livestock. At present, only investigations were carried out on the genetic variation in Exon-8, Intron-8 and Exon-10 of the yak GHR gene (VARVIO et al. 2008), no other information on the yak GHR gene is available. The purposes of this study were to – analyze the structural features of the 5’ flanking region of the yak GHR gene – compare the 5’ flanking region of yak GHR gene with that of other species of the Bovidae family and – construct the phylogenetic tree to indicate the evolutionary relationship among them.

Assessment of the Risk of Rupture of Intracranial Aneurysms using Three-Dimensional Cerebral Digital Subtraction Angiography

The aim of this study was to develop an improved binary logistic regression model for predicting the risk of intracranial aneurysm rupture. A cohort of patients ( n = 37) with aneurysms underwent three-dimensional digital subtraction angiography examination to measure several morphological parameters of the aneurysm. The aspect ratio (height/neck size) and the size ratio (length/mean diameter of parent vessel) were also calculated. All the morphological parameters combined with the aneurysm location and the patient's baseline data were used to derive a backward binary logistic regression model. In order to validate the model, it was applied to another independent cohort of 19 patients with aneurysms. The model had sensitivity, specificity and accuracy of 84.6%, 66.7% and 78.9%, respectively. This binary logistic regression model of aneurysm rupture risk identified the status of an aneurysm with high accuracy and could form the basis of more complex models in the future.