Diagnostic accuracy of rapid phIGFBP-I assay for predicting preterm labor in symptomatic patients

OBJECTIVE

To estimate sensitivity, specificity, positive and negative predictive values (PPV, NPV) of insulin-like growth factor binding protein-1 (phIGFBP-1) test in predicting preterm delivery in women with symptoms of preterm labor. Secondary objectives were to compare test characteristics of the phIGFBP-1 and fetal fibronectin (fFN) tests.

STUDY DESIGN

Labor and delivery units in two Calgary hospitals. Subjects were 349 women with suspected labor between 24 and 35 weeks gestational age (GA). Women had cervical phIGFBP-1 test +/- and fFN testing. Sensitivity, specificity, PPV and NPV were estimated. Primary outcome was birth <37 weeks GA.

RESULT

Sensitivity of phIGFBP-1 test for delivery <37 weeks was 0.39; specificity, 0.76; PPV, 0.24; NPV, 0.86. NPV of phIGFBP-1 did not differ greatly from that of fFN testing (0.88).

CONCLUSION

NPV did not differ between phIGFBP-1 and fFN for delivery <37 weeks. Neither test improves on pretest probability of delivery <37 weeks, so clinicians must decide whether the use of either test is justified.

SU-E-T-280: Optimal Angle for a Dual-Field Stanford Technique for TSET

PURPOSE

This study examines the optimal angle for a dual-field Stanford technique for TSET at extended SSD (SSD= 1, 2, 3, 4, 5 m) to predict a readily available optimal angle for any SSD.

METHODS

The optimal angle at various SSDs is found using detector array. The diode array consists of 9 diodes placed on a vertical board with a measured vertical scale with the origin placed at isocenter. The lateral distance ranges from -100 to +75 cm. A square 36×36 cm² field is used to deliver dose in HDTSe- delivery mode with a dose rate 2500 MU/min from a Varian Clinic 2300IX linac. Several pairs of gantry angles for the dual field are used, with the first gantry being 70°-78° and the second being 110° -102°. These Result in a dual field of 90° ± θ (θ = 10° - 20°) to build a suitable flatness profile on the vertical axis for treatment. The best group is chosen to determine the optimal angle for each SSD considered. From these optimal angles, an algorithm is determined for any extended SSD treatment.

RESULTS

It is found that the optimal angle for TSET does change as one varies the SSD. These angle groups are specific for each SSD giving definite markers for the algorithm. At an SSD of 5 m it has been shown that an optimal angle of θ = 106° produces the best flatness on the vertical axis. While at SSD of 4 m, 9 = 18° Conclusions: An algorithm can now be applied for any treatment center considering a dual- field Stanford technique for TSET simplifying the physics commissioning process for the center in consideration.

Pharmacokinetics and biodistribution of paclitaxel-loaded microspheres

Paclitaxel(PTX)-loaded microspheres composed of poly(D,L-lactide-co-glycolide) (PLGA) were prepared by an O/W emulsion solvent evaporation method. This study was designed to investigate the preparation, in vitro release, in vivo pharmacokinetics and tissue distribution of a PTX-loaded microspheres system. Microspheres are characterized according to drug loading, size and shape. With a dynamic light scattering sizer and a transmission electron microscopy, it is shown that the PTX-loaded microspheres had a mean size of approximately 10.24 µm with narrow size distribution and a spherical shape. The in vitro release profiles indicate that the release of PTX from the microspheres exhibit a sustained release behavior. A similar phenomenon is observed in a pharmacokinetic study in rats, in which AUC of the microspheres formulation were 3.7-fold higher than that of PTX injection. The biodistribution study in mice showed that the PTX-loaded microspheres not only decreased drug uptake by liver, but also increased distribution of drug in lung. These results suggest that PTX-loaded microspheres may efficiently load, protect and retain PTX in both in vitro and in vivo environments, and could be a useful drug carrier for i. v. administration of PTX.

Single-nucleotide polymorphisms in the promoter of the growth hormone-releasing hormone receptor gene are associated with growth and reproduction traits in chickens

Growth hormone-releasing hormone receptor (GHRHR) plays a critical role in growth hormone (GH) synthesis, release and regulation in animals. The objective of this study was to investigate variations of the chicken GHRHR gene and their associations with growth and reproduction traits in 768 Beijing You chickens. Results revealed three single nucleotide polymorphisms (SNPs) in the promoter region of the gene (g.-1654A>G, g.-1411A>G and g.-142T>C). Association analysis revealed that the novel SNP g.-1654A>G had significant effects on chicken body weight at 7, 9, 11, 13, 17 weeks of age and the age of first egg as well as egg number at 32, 36 and 40 weeks. Significant association was also observed between g.-1411A>G and g.-142T>C with EN24. Moreover, the age of first egg was distinctly related with g.-142T>C (P < 0.05). Although significant statistical difference was not detected in GHRHR mRNA levels among genotypes of the SNPs (P > 0.05), strong expression variations of the gene were found between the ages 17 and 20 weeks in the population (P < 0.05). These results suggest that the three SNPs in the GHRHR promoter could be used as potential genetic markers to improve the growth and reproductive traits in chickens.

Polymorphisms of NOD2 and the risk of tuberculosis: a validation study in the Chinese population

A genome-wide association study (GWAS) of leprosy reported four specific genetic polymorphisms of NOD2 that were associated with susceptibility to Mycobacterium leprae in China. Considering the role of NOD2 in innate immune defence, we performed a study in a Chinese population to determine whether the same SNPs of NOD2 that were associated with disease caused by M. leprae were also associated with disease caused by Mycobacterium tuberculosis. We performed a frequency-matched case-control study in 1043 patients with pulmonary tuberculosis and 808 unaffected controls. All subjects were >15 years old and were Han Chinese from Jiangsu Province. We extracted DNA from a blood sample from each study participant. SNPs of rs3135499, rs7194886, rs8057341 and rs9302752 in the NOD2 gene were genotyped using a TaqMan-based allelic discrimination system. Using all possible patients with tuberculosis as cases, no significant association was found between the four specific SNPs and the risk of tuberculosis. In a subgroup analysis restricted to cases with bacteriologically confirmed tuberculosis (sputum culture positive), the variant genotype of rs7194886 was significantly associated with an altered risk of tuberculosis. Compared with the CC genotype, individuals carrying the CT/TT genotype of rs7194886 had an increased risk [odds ratio (OR) 1.35, 95% confidence interval (CI) (1.05-1.72)]. The association was stronger among tobacco smokers and males. By haplotype analysis, rs9302752C-rs7194886T was associated with an increased risk of bacteriologically confirmed tuberculosis (sputum culture positive) (P = 0.039), but it was not significant after correcting for multiple comparisons. In summary, genetic polymorphisms of the SNP rs7194886 in the NOD2 gene, which were discovered in the GWAS of leprosy, might also be associated with the pulmonary tuberculosis in the Chinese population.

Analyses of CDC2L1 gene mutations in keloid tissue

BACKGROUND

Keloid disease is the result of a deregulated wound-healing process. Loss of heterozygosity on chromosome 1p36 has been shown to be associated with keloid formation in humans. The cell division cycle 2-like 1 (CDC2L1) gene is known to be essential for eukaryotic cell-cycle control, and has also been mapped to 1p36.

AIM

To verify the possible association between keloid disease and somatic mutation of the CDC2L1 gene on chromosome 1p36.

METHODS

Mutations of the CDC2L1 gene in keloid and healthy skin tissues were screened by denaturing high-performance liquid chromatography, and confirmed by DNA sequencing analysis.

RESULTS

Of the 27 patients with keloid assessed, 21 had mutations. The most prevalent exon affected was exon 7, with 15 patients affected: 10 patients (37%) had a base G deletion at codon 247, and 12 patients (44.4%) had a base A insertion at codon 267 (6 patients (25.9%) had both mutations). The remaining six patients had mutations in exons 11 (codon 433; n = 3) and 14 (codon 520; n = 3). Comparing the keloid skin tissues with the healthy control skin tissues, significant differences were seen between the groups for the base G deletion at codon 247 and the base A insertion at codon 267.

CONCLUSIONS

We have identified a correlation between two exon 7 mutations of the CDC2L1 gene and keloid disease. A further study of protein-kinase activity should be conducted to confirm the functionality of the CDC2L1 gene in the prevention of scar formation.

A transanal procedure using an endoscopic linear stapler for obstructed defecation syndrome: the first Chinese experience

BACKGROUND

Transanal surgery using an endoscopic linear stapler is a recognized, but not widely performed technique for the treatment of obstructed defecation syndrome (ODS). A study of consecutive patients was conducted to evaluate the safety and effectiveness of the technique for the treatment of ODS in Chinese patients.

METHODS

From November 2008 to December 2010, 43 female patients with ODS caused by rectocele and/or rectal intussusception underwent transanal surgery using an endoscopic linear stapler in three Chinese hospitals. Clinical and functional data including the Wexner constipation score and outcome classification were analyzed retrospectively.

RESULTS

The average duration of surgery was 23 ± 4 min (range 15-30 min). Blood loss was 10 ± 2 ml (range 5-15 ml). The average postoperative hospital stay was 5 days (range 4-6 days). The pathologic findings showed that the specimen contained rectal muscle in all patients. Postoperative complications included 4 patients with transient fecal urgency, 3 patients with anorectal pain, and one patient with mild bleeding from the stapled suture line. Three patients reported minor fecal incontinence (Wexner score less than 3). During a median follow-up of 12 months (range, 3-26 months), the mean constipation score improved from preoperative 13.56 to postoperative 5.07 at 1 year (P < 0.05). The outcome at 1 year was excellent in 18 of 43 patients, good in 13, fairly good in 7, and poor in 5. Postoperative defecography was performed in 28 patients. Rectocele disappeared in 15 patients. Rectocele depth was reduced from 34 ± 4 mm preoperatively to 17 ± 3 mm postoperatively (P < 0.05).

CONCLUSION

The transanal procedure using an endoscopic linear stapler is an easy, safe, and effective option for selected patients with ODS. Long-term prospective, randomized, controlled studies are needed to confirm the advantages of this procedure in comparison with the traditional transanal and stapled transanal rectal resection (STARR) techniques.

Diel vertical distribution of early marine phase juvenile pink salmon (Oncorhynchus gorbuscha) and behaviour when exposed to salmon louse (Lepeophtheirus salmonis)

We observed diel vertical migration patterns in juvenile pink salmon ( Oncorhynchus gorbuscha (Walbaum, 1792)) and tested the hypothesis that fish behaviour is altered by exposure to sea lice copepodids. Experiments involved replicated field deployments of a large (9 m) plankton column, which provided a vertical distribution enclosure under natural light and salinity conditions. Diel vertical distributions of juvenile pink salmon were observed during the first 3 weeks of seawater acclimation in both the presence and the absence of the ectoparasitic salmon louse ( Lepeophtheirus salmonis (Krøyer, 1838)). Immediately upon entering seawater, juvenile pink salmon preferred the top 1 m of the water column, but they moved significantly deeper down the vertical water column as seawater acclimation time increased. A significant diel migration pattern was observed, which involved a preference for the surface at night-time, compared with daytime. When fish in the column were exposed to L. salmonis copepodids for 3 h, 43%–62% of fish became infected, fish expanded their vertical distribution range, and significant changes in vertical distribution patterns were observed.

Pharmacokinetics of a novel amoxicillin/colistin suspension after intramuscular administration in pigs

An amoxicillin (AMO) or colistin (COS) oil suspension was developed and corresponding pharmacokinetics studies were conducted in pigs after i.m. injection. The combination product is a white- to cream-colored oil suspension which is easy to be re-dispersed. Settling volume ratio, syringeability and flowability of the product is well consistent with the technical standards set by the Ministry of Agriculture of People's Republic of China. Two studies were conducted to investigate the pharmacokinetics of the combination product in swine. First, the pharmacokinetics of the combination product was compared with those of the same products merely removing either AMO or COS. No significant change in the major pharmacokinetic parameters (C(max) , T(max) , MRT, t(1/2λ) , AUC and AUMC) was observed when either component was removed from the combination product, indicating that AMO and COS do not interfere with each other in their absorption and distribution in the tissue when used as a combination. Second, the pharmacokinetics of the combination product was compared with that of their respective single products. It was found that the apparent elimination half-lives (t(1/2λ) ) of AMO and COS in combination product were 6.38 and 8.09 h, which were 2.40 and 2.38 times longer than the single products, respectively. Thus, the novel AMO/COS suspension extended significantly the half-life of both drugs to maintain a longer drug residence time in pigs when compared to their single products.

Clinical outcome and quality of life after surgery for peri-acetabular metastases

We set out to determine the impact of surgery on quality of life and function in patients who had undergone surgery for symptomatic peri-acetabular metastases. From a prospective database we retrospectively reviewed 46 consecutive patients who had been treated operatively between June 2003 and June 2009. The mean age of the patients was 56.4 years (20 to 73) and the mean post-operative follow-up was 19.2 months (4 to 70). Functional evaluation and quality-of-life assessments were performed. At the most recent follow-up, 26 patients (56.5%) were alive. Their median survival time was 25.0 months. Ten major postoperative complications had occurred in eight patients (17.4%). The mean post-operative Musculoskeletal Tumor Society score (MSTS 93) was 56.3% (6.7% to 90.0%). Improvement in the Eastern Cooperative Oncology Group (ECOG) performance status was seen in 32 patients (69.6%). On the European Organisation for Research and Treatment of Cancer core quality-of-life questionnaire (QLQ-C30) measure of global health status there was a statistically significant improvement from the patients’ pre-operative status (42.8 (sd 13.7)) to that found at the latest follow-up (58.0 (sd 12.5)) (p = 0.001). The only statistically significant change in the nine symptom domains of the QLQ-C30 was a reduction in the mean level of pain (from 59.1 to 29.5 (out of 100)) (p < 0.001).

Surgery for patients with peri-acetabular metastases reduces pain and improves their quality of life, and has a low rate of surgical complications.

Changes in cortical bone response to high-fat diet from adolescence to adulthood in mice

Diabetic obesity is associated with increased fracture risk in adults and adolescents. We find in both adolescent and adult mice dramatically inferior mechanical properties and structural quality of cortical bone, in agreement with the human fracture data, although some aspects of the response to obesity appear to differ by age.

INTRODUCTION

The association of obesity with bone is complex and varies with age. Diabetic obese adolescents and adult humans have increased fracture risk. Prior studies have shown reduced mechanical properties as a result of high-fat diet (HFD) but do not fully address size-independent mechanical properties or structural quality, which are important to understand material behavior.

METHODS

Cortical bone from femurs and tibiae from two age groups of C57BL/6 mice fed either HFD or low-fat diet (LFD) were evaluated for structural and bone turnover changes (SEM and histomorphometry) and tested for bending strength, bending stiffness, and fracture toughness. Leptin, IGF-I, and non-enzymatic glycation measurements were also collected.

RESULTS

In both young and adult mice fed on HFD, femoral strength, stiffness, and toughness are all dramatically lower than controls. Inferior lamellar and osteocyte alignment also point to reduced structural quality in both age groups. Bone size was largely unaffected by HFD, although there was a shift from increasing bone size in obese adolescents to decreasing in adults. IGF-I levels were lower in young obese mice only.

CONCLUSIONS

While the response to obesity of murine cortical bone mass, bone formation, and hormonal changes appear to differ by age, the bone mechanical properties for young and adult groups are similar. In agreement with human fracture trends, adult mice may be similarly susceptible to bone fracture to the young group, although cortical bone in the two age groups responds to diabetic obesity differently.

Effects of interval between fusion and activation, cytochalasin B treatment, and number of transferred embryos, on cloning efficiency in goats

To improve the efficiency of somatic cell nuclear transfer (SCNT) in goats, we evaluated the effects of the interval between fusion and activation (1 to 5 h), cytochalasin B (CB) treatment after electrofusion, and the number of transferred embryos on the in vivo and in vitro development of cloned caprine embryos. The majority of the reconstructed embryos had condensed chromosomes and metaphase-like chromosomes at 2 and 3 h after fusion; cleavage and blastocyst rates from those two groups were higher (P < 0.05) than those of embryos activated 1, 4, or 5 h after fusion. Treatment with CB between fusion and activation improved in vitro and in vivo development of nuclear transfer (NT) goat embryos by reducing the fragmentation rate (P < 0.05). Although there were no significant differences in NT efficiency, pregnancy rate and kids born per recipient were increased by transfer of 20 or 30 embryos per recipient compared with 10 embryos. We concluded that CB treatment for 2 to 3 h between fusion and activation was an efficient method for generating cloned goats by somatic cell NT. In addition, increasing the number of embryos transferred to each recipient resulted in more live offspring from fewer recipients.

Water equivalent path length measurement in proton radiotherapy using time resolved diode dosimetry

PURPOSE

To verify water equivalent path length (WEPL) before treatment in proton radiotherapy using time resolved in vivo diode dosimetry.

METHODS

Using a passively scattered range modulated proton beam, the output of a diode driving a fast current-to-voltage amplifier is recorded at a number of depths in a water tank. At each depth, a burst of overlapping single proton pulses is observed. The rms duration of the burst is computed and the resulting data set is fitted with a cubic polynomial.

RESULTS

When the diode is subsequently set to an arbitrary depth and the polynomial is used as a calibration curve, the "unknown" depth is determined within 0.3 mm rms.

CONCLUSIONS

A diode or a diode array, placed (for instance) in the rectum in conjunction with a rectal balloon, can potentially determine the WEPL at that point, just prior to treatment, with submillimeter accuracy, allowing the beam energy to be adjusted. The associated unwanted dose is about 0.2% of a typical single fraction treatment dose.

The sodium channel band shapes the response to electric stimulation in retinal ganglion cells

To improve the quality of prosthetic vision, it is desirable to understand how targeted retinal neurons respond to stimulation. Unfortunately, the factors that shape the response of a single neuron to stimulation are not well understood. A dense band of voltage-gated sodium channels within the proximal axon of retinal ganglion cells is the site most sensitive to electric stimulation, suggesting that band properties are likely to influence the response to stimulation. Here, we examined how three band properties influence sensitivity using a morphologically realistic ganglion cell model in NEURON. Longer bands were more sensitive to short-duration pulses than shorter bands and increasing the distance between band and soma also increased sensitivity. Simulations using the known limits of band length and location resulted in a sensitivity difference of approximately 2. Additional simulations tested how changes to sodium channel conductance within the band influenced threshold and found that the sensitivity difference increased to a factor of nearly 3. This is close to the factor of 5 difference measured in physiological studies suggesting that band properties contribute significantly to the sensitivity differences found between different types of retinal neurons.