Orthopedics research output from China, USA, UK, Japan, Germany and France: A 10-year survey of the literature

BACKGROUND

In the past decade, researchers have made great progress in the field of Orthopedics. However, the research status of different countries is unclear. To summarize the number of published articles, we assessed the cumulative impact factors in top orthopedic journals. The aims of the study were to measure: 1) the quality and quantity of publications in orthopedics-related journals from China and other five counties, 2) the trend of the number of publications in orthopedics-related journals.

METHODS

The related journals were selected based on the 2014 scientific citation index (SCI) and articles were searched based on the PubMed database. To assess the quantity and quality of research output, the number of publications including clinical trials, randomized controlled trials, meta-analyses, case reports, reviews, citations, impact factors, number of articles in the top 10 journals and most popular journals were recorded.

RESULTS

A total of 143,138 orthopedics articles were published from 2005 to 2014. The USA accounts for 24.9% (35,763/143,138) of the publications, followed by UK (7878/143,138 (5.5%)), Japan (7133/143,138 (5.0%)), Germany (5942/143,138 (4.2%)), China (4143/143,138 (2.9%)) and France (2748/143,138 (1.9%)). The ranking for accumulated impact factors as follows: USA, UK, Japan, Germany, France and China. The mean impact factor's order is USA, China, Germany, Japan, France, UK, and interestingly the mean impact factors in Japan is similar to the Germany in 2005-2014. The USA had the highest percentage of articles in the top 10 journals, while China owns the least. The USA had the highest number of average citations, while Japan had lowest number of average citations.

CONCLUSIONS

According to this study, we can conclude that the USA has had been leading the orthopedics research in the past 10 years. Although China still falls behind, it has made considerable progress in the orthopedics research, not only in quantity but also quality.

LEVEL OF EVIDENCE

IV.

Host Cell Dependence of Human Immunodeficiency Virus Type-1 Drug Resistance Profiles and Tissue Culture Selection Patterns

Clinical isolates of the human immunodeficiency virus type 1 (HIV-1) displayed differential sensitivity to antiviral nucleosides depending on the type of host cell employed for viral propagation. Viruses derived from the peripheral blood mononuclear cells (PBMC) of subjects on prolonged 3′-azido-3′-deoxythymidine (AZT) therapy behaved as AZT-resistant when tested in either cord blood mononuclear cells or MT-4 cells but as relatively drug-sensitive in the U-937 monocytic cell line. Viruses derived from monocytes/ macrophages of the same individuals behaved as drug-sensitive in all cells tested. It was also shown that cloned recombinant viruses, which contained defined resistance-conferring mutations at either position 65 or 184 in the HIV pol gene, were generally less susceptible to each of 2′-3′-dideoxyinosine (ddl), 2′,3′-dideoxycytidine (ddC) and the (-)enantiomer of 2′,3′-dideoxy-3′thiacytidine (3TC) in MT-4 cells than in any of PBMC, cord blood mononuclear cells (CBMC) or Jurkat cells. Finally, resistance against each of AZT, ddl and ddC could be selected for more easily using MT-4 cells than CBMC or Jurkat lymphocytes and not at all with the U-937 monocytic cell line.

A New Pulse Pileup Rejection Method Based on Position Shift Identification

Pulse pileup events degrade the signal-to-noise ratio (SNR) of nuclear medicine data. When such events occur in multiplexed detectors, they cause spatial misposition, energy spectrum distortion and degraded timing resolution, which leads to image artifacts. Pulse pileup is pronounced in PETbox4, a bench top PET scanner dedicated to high sensitivity and high resolution imaging of mice. In that system, the combination of high absolute sensitivity, long scintillator decay time (BGO) and highly multiplexed electronics lead to a significant fraction of pulse pileup, reached at lower total activity than for comparable instruments. In this manuscript, a new pulse pileup rejection method named position shift rejection (PSR) is introduced. The performance of PSR is compared with a conventional leading edge rejection (LER) method and with no pileup rejection implemented (NoPR). A comprehensive digital pulse library was developed for objective evaluation and optimization of the PSR and LER, in which pulse waveforms were directly recorded from real measurements exactly representing the signals to be processed. Physical measurements including singles event acquisition, peak system sensitivity and NEMA NU-4 image quality phantom were also performed in the PETbox4 system to validate and compare the different pulse pile-up rejection methods. The evaluation of both physical measurements and model pulse trains demonstrated that the new PSR performs more accurate pileup event identification and avoids erroneous rejection of valid events. For the PETbox4 system, this improvement leads to a significant recovery of sensitivity at low count rates, amounting to about 1/4th of the expected true coincidence events, compared to the LER method. Furthermore, with the implementation of PSR, optimal image quality can be achieved near the peak noise equivalent count rate (NECR).

Direct synthesis of layered double hydroxide nanosheets for efficient siRNA delivery

In this paper, we have developed a simple yet efficient method to prepare stable single-sheet MgAl-layered double hydroxide (MA-NS) suspensions without using organic solvents or surfactants.

Risk factors for hemorrhagic cystitis in pediatric allogeneic hematopoietic stem cell transplant recipients

BACKGROUND

Hemorrhagic cystitis (HC) results in significant morbidity among hematopoietic stem cell transplant (HSCT) recipients. Several potential causes for HC have been postulated, including viral infection, but definitive evidence is lacking, particularly in pediatric HSCT patients.

METHODS

Ninety pediatric HSCT recipients were prospectively tested on a weekly basis for adenovirus (ADV) and BK virus (BKV) by quantitative real-time polymerase chain reaction in blood and urine samples. Results were correlated with the occurrence of grade II-IV HC. The odds ratio (OR) of HC (95% confidence interval) for BKV ≥1 × 10(9) copies/mL of urine was 7.39 (1.52, 35.99), with a P-value of 0.013. Those with acute graft-versus-host disease (aGVHD) also had higher odds of developing HC, with an OR of 5.34. Given a 20% prevalence rate of HC, positive and negative predictive values of 29% and 95% were seen with a cutoff of 10(9) copies/mL.

RESULTS

BK viremia did not reach significance as a risk factor for development of HC (P = 0.06). Only 8 patients showed ADV viruria and 7 showed ADV viremia; all had low viral loads and 4 had no evidence of HC.

CONCLUSION

HC in pediatric HSCT is correlated most strongly to elevated urinary viral load of BKV and to aGVHD, but less strongly to BK viremia.

Promoter polymorphism T-786C, 894G→T at exon 7 of endothelial nitric oxide synthase gene are associated with risk of osteoporosis in Sichuan region male residents

OBJECTIVE

To investigate the association between genetic polymorphism of T-786C in promoter region, 894G→T at exon 7 of endothelial nitric oxide synthase (eNOS) gene and osteoporosis (OP) disease.

METHOD

The genotypes of 350 patients with osteoporosis and 350 healthy controls were detected by polymerase chain reaction (PCR) and DNA sequencing. The allele ratios and genotype distributions in the patients and controls were assessed using the Pearson χ(2)-test. Odds ratios (OR) with two tailed P-values and 95% confidence intervals (CI) were calculated as a measure of the association of the eNOS genotypes with OP.

RESULT

the C allele distribution frequency of T-786C eNOS gene in OP group (8.5%) was significantly higher than that in control group (3.9%), relative risk (OR) of OP associated with the CC genotype was 2.68 (95% CI, 0.92 to 1.37). The T allele frequency of 894G→T at exon 7 in eNOS gene in OP group (11.5%) was also significantly higher than that in control group (5.2%), OR of OP associated with the TT genotype was 2.60 (all P<0.05).

CONCLUSION

The analysis results indicated that both T-786C in promoter region and 894G→T at exon 7 of eNOS gene might be genetic predisposal factors of OP, these polymorphisms may be independently or synergic with other loci to have an impact on the incidence of OP.

Genetic association analysis between polymorphisms of HAIRY-AND-ENHANCER-OF SPLIT-7 and congenital scoliosis

OBJECTIVE

We explored the association between genetic polymorphisms of HAIRY-AND-ENHANCER-OF-SPLIT-7 (HES7) and congenital scoliosis (CS) in 246 cases of congenital scoliosis and non-congenital controls, in which the age and sex were fully matched. All participants were Chinese Han population.

METHODS

The genome DNA was extracted from peripheral blood sample. Two SNPs were defined for HES7 using NCBI database. The genotypes of two SNPs were determined by SNP stream UHT Genotyping System.

RESULTS

Polymorphisms were found in both SNPs and in accordance with Hardy-Weinberg equilibrium. For SNP rs3027279, the difference of two alleles (C and A) frequencies between CS and control groups Was statistically significant. Analysis also showed the difference of two genotypes (C/C and C/A) frequencies between two groups was significant (χ(2)=5.857, P<0.05). For SNP rs1442849, both difference of two alleles (A and G) frequencies and difference of three genotypes (G/G, G/A and AA) frequencies between two groups were shown statistically significant.

CONCLUSIONS

The unconditional Logistic regression analysis showed A/A genotype of SNP rsl442849 may be a protective factor (P=0.018<0.05, OR-0.35, 95% CI=0.17-0.74) for the onset of CS, while C/A genotype of SNP rs3027279 increased the onset risk (P=0.015<0.05, OR=1.93, 95% CI=1.13-3.30) of CS. Linkage disequilibrium analysis demonstrated the existence of linkage disequilibrium between the two SNPs.

A DOI Detector With Crystal Scatter Identification Capability for High Sensitivity and High Spatial Resolution PET Imaging

A new phoswich detector is being developed at the Crump Institute, aiming to provide improvements in sensitivity, and spatial resolution for PET. The detector configuration is comprised of two layers of pixelated scintillator crystal arrays, a glass light guide and a light detector. The annihilation photon entrance (top) layer is a 48 × 48 array of 1.01 × 1.01 × 7 mm³ LYSO crystals. The bottom layer is a 32 × 32 array of 1.55 × 1.55 × 9 mm³ BGO crystals. A tapered, multiple-element glass lightguide is used to couple the exit end of the BGO crystal array (52 × 52 mm²) to the photosensitive area of the Position Sensitive Photomultiplier Tube (46 × 46 mm²), allowing the creation of flat panel detectors without gaps between the detector modules. Both simulations and measurements were performed to evaluate the characteristics and benefits of the proposed design. The GATE Monte Carlo simulation indicated that the total fraction of the cross layer crystal scatter (CLCS) events in singles detection mode for this detector geometry is 13.2%. The large majority of these CLCS events (10.1% out of 13.2%) deposit most of their energy in a scintillator layer other than the layer of first interaction. Identification of those CLCS events for rejection or correction may lead to improvements in data quality and imaging performance. Physical measurements with the prototype detector showed that the LYSO, BGO and CLCS events were successfully identified using the delayed charge integration (DCI) technique, with more than 95% of the LYSO and BGO crystal elements clearly resolved. The measured peak-to-valley ratios (PVR) in the flood histograms were 3.5 for LYSO and 2.0 for BGO. For LYSO, the energy resolution ranged from 9.7% to 37.0% full width at half maximum (FWHM), with a mean of 13.4 ± 4.8%. For BGO the energy resolution ranged from 16.0% to 33.9% FWHM, with a mean of 18.6 ± 3.2%. In conclusion, these results demonstrate that the proposed detector is feasible and can potentially lead to a high spatial resolution, high sensitivity and DOI PET system.

[Clinical features and proportion analysis of adult hip fractures at 11 hospitals in Southwest China from 2010 to 2011]

OBJECTIVE

To analyze the clinical feature and constituent ratio of adult hip fractures in Southwest China.

METHODS

The data of adult inpatients and outpatients with hip fractures treated between January 2010 and December 2011 in 11 hospitals of the Southwest China were collected and analyzed. The data includes gender, age, age distribution and fracture pattern according to AO classification.

RESULTS

There were a total of 2,833 adult hip fractures, including 1,340 (47.30%) males and 1,493 (52.70%) females, with a male-to-female incidence ratio of 1: 1.11 and a mean age of (66±18) years. The highest frequency of hip fractures was seen in the 71 to 85 years age group (42.18%, 1,195/2,833). There were 844 fractures (29.79%) in the young and middle-aged group (16-<60 years) and 1 898 fractures (70.21%) in the geriatric group (≥60 years). Men had a higher rate than women (men: 577 fractures, 68.4%) in the young and middle-aged group, while women had a higher rate than men (women: 1,226 fractures, 61.64%) in the geriatric group, with a significant difference in the sex distribution between the two groups (χ2=214.001, P<0.01). The proportion of intertrochanteric fracture (type 31-A), femoral neck (type 31-B) and femoral head fracture (type 31-C) was 46.59%, 49.74% and 3.67% respectively. The highest frequency of the sub-type in each fracture type was type 31-A2, type 31-B2 and type 31-C2.

CONCLUSIONS

Women have a higher rate than men in Southwest China. Geriatric patients are more than the young and middle-aged patients. The femoral neck fractures, intertrochanteric fractures and femoral head fractures are in descending orders according to the proportion of the three different hip fractures.

Effects of Elderberry Juice from Different Genotypes on Oxidative and Inflammatory Responses in Microglial Cells

Many species of berries are nutritious food and offer health benefits. However, among the different types of berries, information on health effects of American elderberries (Sambucus nigra subsp. canadensis) has been lacking and little is known about whether elderberry consumption can confer neuroprotective effects on the central nervous system. Microglial cells constitute a unique class of immune cells and exhibit characteristic properties to carry out multifunctional duties in the brain. Activation of microglial cells has been implicated in brain injury and in many types of neurodegenerative diseases. Our recent studies demonstrated the ability for endotoxin (lipopolysaccharide, LPS) and interferon gamma (IFNγ) to induce reactive oxygen species (ROS) and nitric oxide (NO) in murine microglial cells (BV-2) through activating NADPH oxidase and the MAPK pathways. In this study, BV-2 microglial cells were used to examine effects of elderberry juice obtained from different genotypes on oxidative and inflammatory responses induced by LPS and IFNγ. Results show that 'Wyldewood' extract demonstrated antioxidant properties by inhibiting IFNγ-induced ROS production and p-ERK1/2 expression. On the other hand, most juice extracts exerted small effects on LPS-induced NO production and some extracts showed an increase in NO production upon stimulation with IFNγ. The disparity of responses on ROS and NO production from different extracts suggests possible presence of unknown endogenous factor(s) in the extract in promoting the IFNγ-induced iNOS synthesis pathway.

Optimization of the Energy Window for PETbox4, a Preclinical PET Tomograph With a Small Inner Diameter

Small animal positron emission tomography (PET) systems are often designed by employing close geometry configurations. Due to the different characteristics caused by geometrical factors, these tomographs require data acquisition protocols that differ from those optimized for conventional large diameter ring systems. In this work we optimized the energy window for data acquisitions with PETbox4, a 50 mm detector separation (box-like geometry) pre-clinical PET scanner, using the Geant4 Application for Tomographic Emission (GATE). The fractions of different types of events were estimated using a voxelized phantom including a mouse as well as its supporting chamber, mimicking a realistic mouse imaging environment. Separate code was developed to extract additional information about the gamma interactions for more accurate event type classification. Three types of detector backscatter events were identified in addition to the trues, phantom scatters and randoms. The energy window was optimized based on the noise equivalent count rate (NECR) and scatter fraction (SF) with lower-level discriminators (LLD) corresponding to energies from 150 keV to 450 keV. The results were validated based on the calculated image uniformity, spillover ratio (SOR) and recovery coefficient (RC) from physical measurements using the National Electrical Manufacturers Association (NEMA) NU-4 image quality phantom. These results indicate that when PETbox4 is operated with a more narrow energy window (350-650 keV), detector backscatter rejection is unnecessary. For the NEMA NU-4 image quality phantom, the SOR for the water chamber decreases by about 45% from 15.1% to 8.3%, and the SOR for the air chamber decreases by 31% from 12.0% to 8.3% at the LLDs of 150 and 350 keV, without obvious change in uniformity, further supporting the simulation based optimization. The optimization described in this work is not limited to PETbox4, but also applicable or helpful to other small inner diameter geometry scanners.

Synthesis of conjugated linoleic acid by the linoleate isomerase complex in food-derived lactobacilli

AIMS

To assess strains of lactobacilli for their capacity to produce functional fatty acid-conjugated linoleic acid. To assess the linoleate isomerase for CLA production in the most efficient CLA producer.

METHODS AND RESULTS

In this study, strains of food-derived lactobacilli were cultured in media with linoleic acid and CLA production was assessed. Most of the selected strains produced CLA at different levels, with Lactobacillus plantarum ZS2058 being the most efficient CLA producer converting over 50% of linoleic acid to c9, t11-CLA and t9, t11-CLA. Some intermediates 10-hydroxy-cis-12-octadecenoic acid, 10-oxo-cis-12-octadecenoic acid and 10-oxo-trans-11-octadecenoic acid were determined via GC-MS. The genes coding the multicomponent linoleate isomerase containing myosin-cross-reactive antigen, short-chain dehydrogenase/oxidoreductase and acetoacetate decarboxylase for CLA production in Lact. plantarum ZS2058 were cloned and expressed in Escherichia coli. With the mixture of recombinant E. coli, c9, t11-CLA and three kinds of intermediates were produced from linoleic acid, which were in line with those in the lactobacilli.

CONCLUSIONS

The ability for CLA production by lactobacilli exhibited variation. Lactobacillus plantarum and Lact. bulgaricus were the most efficient producers in the selected strains. Lact. plantarum ZS2058 converted linoleic acid to CLAs with 10-hydroxy-cis-12-octadecenoic acid, 10-oxo-cis-12-octadecenoic acid and 10-oxo-trans-11-octadecenoic acid as intermediates. The multiple-step reactions for CLA production catalysed by multicomponent linoleate isomerase in Lact. plantarum ZS2058 were confirmed successfully.

SIGNIFICANCE AND IMPACT OF THE STUDY

Multicomponent linoleate isomerase provides important results for the illustration of the mechanism for CLA production in lactic acid bacteria. Food-derived lactobacilli with CLA production ability offers novel opportunities for functional foods development.

Safe and efficient local gene delivery into skeletal muscle via a combination of Pluronic L64 and modified electrotransfer

Efficient DNA electrotransfer into muscles can be achieved by combining two types of electronic pulses sequentially: short high-voltage (HV) pulse for the cell electropermeabilization and long low-voltage (LV) pulse for the DNA electrophoresis into cells. However, the voltages currently applied can still induce histological and functional damages to tissues. Pluronic L64 has been considered as a molecule possessing cell membrane-disturbing ability. For these reasons, we hope that L64 can be used as a substitute for the HV pulse in cell membrane permeabilization, and a safe LV pulse may still keep the ability to drive plasmid DNA across the permeabilized membrane. In this work, we optimized the electrotransfer parameters to establish a safe and efficient procedure using a clinically applied instrument, and found out that the critical condition for a successful combination of electrotransfer with L64 was that the injection of plasmid/L64 mixture should be applied 1 h before the electrotransfer. In addition, we revealed that the combined procedure could not efficiently transfer plasmid into solid tumor because the uncompressed plasmid may rapidly permeate the leaky tumor vessels and flow away. Altogether, the results demonstrate that the combined procedure has the potential for plasmid-based gene therapy through safe and efficient local gene delivery into skeletal muscles.

Cardiorenal metabolic syndrome and diabetic cognopathy

The prevalence of the cardiorenal metabolic syndrome (CRS) is increasing in parallel with obesity, type 2 diabetes mellitus, Alzheimer's disease, and other forms of dementia. Along with metabolic, inflammatory, and immunological abnormalities, there is maladaptive structural remodeling of the heart, kidney, and brain. The term 'diabetic cognopathy' (DC) may be used when discussing functional and structural changes in the brain of the diabetic patient. DC likely represents an advanced form of these changes in the brain that evolve with increasing duration of the CRS and subsequent clinical diabetes. We posit that DC develops due to a convergence of aging, genetic and lifestyle abnormalities (overnutrition and lack of exercise), which result in multiple injurious metabolic and immunologic toxicities such as dysfunctional immune responses, oxidative stress, inflammation, insulin resistance, and dysglycemia (systemically and in the brain). These converging abnormalities may lead to endothelial blood-brain barrier tight junction/adherens junction (TJ/AJ) complex remodeling and microglia activation, which may result in neurodegeneration, impaired cognition, and dementia. Herein, we describe the brain ultrastructural changes evolving from a normal state to maladaptive remodeling in rodent models of CRS including microglia activation/polarization and attenuation and/or loss of the TJ/AJ complexes, pericytes and astrocytes of the neurovascular unit. Further, we discuss the potential relationship between these structural changes and the development of DC, potential therapeutic strategies, and future directions.

Pressure and inflammatory stimulation induced increase of cadherin-11 is mediated by PI3K/Akt pathway in synovial fibroblasts from temporomandibular joint

OBJECTIVE

The goal of the study was to investigate the expression of cadherin-11 in synovial fibroblasts (SFs) under mechanical or inflammatory stimuli, and its potential relationship with PI3K/Akt signaling pathway.

METHODS

SFs separated from rat temporomandibular joint (TMJ) were treated with hydrostatic pressures (HP) of 30, 60, 90, and 120 kPa, as well as tumor necrosis factor-α (TNF-α) for 12, 24, 48, and 72 h. The location of cadherin-11 was observed by immunofluorescence microscopy, and its expression was detected by real-time PCR and Western blot. We also studied the activation of PI3K/Akt signaling pathway in SFs with HP or TNF-α stimulation.

RESULTS

The results showed that increased expression of cadherin-11 could be found in the cell-cell contact site of SFs in response to HP and inflammatory stimulation. The mRNA and protein expression of cadherin-11 was positively correlated with the intensity of HP and the duration time of TNF-α treatment. Increased expression of vascular endothelial growth factor-D (VEGF-D) and activation of Akt were also found. Treatment with PI3K inhibitor LY294002 attenuated the pressure or inflammatory cytokine induction increases of cadherin-11, VEGF-D, and FGF-2 both in mRNA and protein levels.

CONCLUSIONS

These findings suggest that cadherin-11 may play important roles in SFs following exposure to mechanical loading and inflammatory stimulation. In addition, PI3K/Akt pathway was associated with pressure or inflammation-induced cadherin-11 expression, which may involve in the pathogenesis of temporomandibular diseases.

Association of the polymorphism of MMP2 with the risk and severity of lumbar disc degeneration in the Chinese Han population

OBJECTIVE

The present study aimed to determine whether the -735 C/T polymorphism of the Matrix Metalloproteinase 2 (MMP2) gene is associated with the risk and severity of lumbar disc degeneration (LDD) in the Chinese Han population.

PATIENTS AND METHODS

A total of 1008 patients with LDD and 906 healthy controls were enrolled in this study. The grade of disc degeneration was determined according to Schneiderman's classification for Magnetic Resonance Imaging (MRI). The -735 C/T polymorphism of MMP2 was genotyped using polymerase chain reaction and the restriction fragment length polymorphism method.

RESULTS

The genotype frequency of the -735 C/T polymorphism was in agreement with the Hardy-Weinberg equilibrium (p = 0.087). The frequencies of the -735CT and TT genotypes were significantly lower among LDD patients compared with normal controls (p < 0.001); CT and TT genotype were significantly associated with a decreased risk of LDD compared with the CC genotype (for TT genotype, p = 0.031; OR 0.413; 95% CI 0.184-0.924; for CT genotype, p < 0.001, OR 0.645, 95% CI 0.506-0.822). Patients with LDD showed significantly higher frequencies of the C allele than normal controls (p < 0.001), T allele was significantly associated with a decreased risk of LDD compared with the C allele (p < 0.001; OR 0.631; 95% CI 0.508-0.783). In addition, the -735TT and CT genotypes, as well as the T allele were associated with lower degenerative grades of LDD compared with CC genotype and the C allele, respectively (both p < 0.001).

CONCLUSIONS

The -735 C/T polymorphism of MMP2 may be associated with the risk and severity of LDD in the Chinese Han population.

NEMA NU-4 performance evaluation of PETbox4, a high sensitivity dedicated PET preclinical tomograph

PETbox4 is a new, fully tomographic bench top PET scanner dedicated to high sensitivity and high resolution imaging of mice. This manuscript characterizes the performance of the prototype system using the National Electrical Manufacturers Association NU 4-2008 standards, including studies of sensitivity, spatial resolution, energy resolution, scatter fraction, count-rate performance and image quality. The PETbox4 performance is also compared with the performance of PETbox, a previous generation limited angle tomography system. PETbox4 consists of four opposing flat-panel type detectors arranged in a box-like geometry. Each panel is made by a 24 × 50 pixelated array of 1.82 × 1.82 × 7 mm bismuth germanate scintillation crystals with a crystal pitch of 1.90 mm. Each of these scintillation arrays is coupled to two Hamamatsu H8500 photomultiplier tubes via a glass light guide. Volumetric images for a 45 × 45 × 95 mm field of view (FOV) are reconstructed with a maximum likelihood expectation maximization algorithm incorporating a system model based on a parameterized detector response. With an energy window of 150-650 keV, the peak absolute sensitivity is approximately 18% at the center of FOV. The measured crystal energy resolution ranges from 13.5% to 48.3% full width at half maximum (FWHM), with a mean of 18.0%. The intrinsic detector spatial resolution is 1.5 mm FWHM in both transverse and axial directions. The reconstructed image spatial resolution for different locations in the FOV ranges from 1.32 to 1.93 mm, with an average of 1.46 mm. The peak noise equivalent count rate for the mouse-sized phantom is 35 kcps for a total activity of 1.5 MBq (40 µCi) and the scatter fraction is 28%. The standard deviation in the uniform region of the image quality phantom is 5.7%. The recovery coefficients range from 0.10 to 0.93. In comparison to the first generation two panel PETbox system, PETbox4 achieves substantial improvements on sensitivity and spatial resolution. The overall performance demonstrates that the PETbox4 scanner is suitable for producing high quality images for molecular imaging based biomedical research.

FcγRI is required for TGFβ2-treated macrophage-induced tolerance

Macrophages treated with TGFβ2 (TGFβ2-Mϕ) and antigen are highly tolerogenic in vivo, and induce antigen-specific and long-lasting tolerance in both naïve and primed mice via induction of suppressor/regulatory T cells. In this study, we examined the molecular pathways, including the requirements for Smad-dependent signaling, that are involved in the induction and function of tolerogenic TGFβ2-Mϕ. Treatment of murine macrophages with TGFβ2 induced translocation of Smad2/3 to the nucleus, and impairment of Smad3-, but not Smad2-, dependent signaling inhibited the tolerogenic function of a TGFβ2-treated murine macrophage cell line. Gene expression in murine macrophages treated with TGFβ2 was evaluated by microarray analysis. The FcγRI gene was one of a number of immune-related genes differentially expressed in TGFβ2-Mϕ, and appeared to be critical for tolerance in this system, since TGFβ2-Mϕ from FcγRI deficient mice were unable to induce tolerance. The role that FcγRI plays in TGFβ2-Mϕ-mediated tolerance is currently unclear. The results of this study provide important information about the factors that are critical for the induction of TGFβ2-Mϕ-mediated tolerance, and a better understanding of these mechanisms could lead to the development of more effective tolerance-inducing strategies for the treatment of autoimmune/inflammatory diseases.

Trepanation and curettage treatment for acute implant periapical lesions

Six dental implants in six patients with periapical lesions were inserted and underwent trepanation and thorough curettage. During surgery, the lesion area was irrigated with copious natural saline and chlorhexidine and the bone defects were treated with tetracycline paste. The six implants were stable and asymptomatic postoperatively. The implants were loaded after 3 months. Radiologically, the radiolucency in the apical part disappeared gradually. These prostheses have functioned satisfactorily with no further complication during the follow-up period. For cases in which small lesions initially appear soon after implant placement, trepanation and curettage of the periapical lesion without resection of the apical part of the implant or bone substitute material and/or autogenous bone grafting is an effective management option. A rapid and exact diagnosis is important for treating implant periapical lesions.

Oxidation of Aluminum Nitride for Defect Characterization

The thermal oxidation of aluminum nitride was developed as a means to study defects in bulk aluminum nitride crystals. The oxidation kinetics was established for the dry oxidation of highly textured AlN polycrystals produced by sublimation-recombination crystal growth in a tungsten furnace. Despite seeding on polycrystalline tungsten, the grains were predominantly [0001] oriented as verified by electron backscattering diffraction (EBSD). The oxidation rate is dependent on the crystal’s orientation, polarity, stress, and surface condition, thus oxidation decorates grain boundaries, polishing scratches, and inversion domains by producing oxide layers of different thicknesses. The initial oxidation rate of nitrogen polar (0001) AlN is approximately 25% faster than on aluminum polar crystals. Low temperature (800 °C) dry oxidation produced an amorphous oxide layer and generated a high density of defects (vacancies, stacking faults, and dislocations) in the nitride near the oxide/nitride interface, as observed by cross-sectional transmission electron microscopy. In contrast, high temperature oxidation (1000 °C) produced a crystalline oxide layer, and left the nitride free of observable defects.

Growth and characterization of ceria thin films and Ce-doped γ-Al2O3 nanowires using sol-gel techniques

γ-Al(2)O(3) is a well known catalyst support. The addition of Ce to γ-Al(2)O(3) is known to beneficially retard the phase transformation of γ-Al(2)O(3) to α-Al(2)O(3) and stabilize the γ-pore structure. In this work, Ce-doped γ-Al(2)O(3) nanowires have been prepared by a novel method employing an anodic aluminium oxide (AAO) template in a 0.01 M cerium nitrate solution, assisted by urea hydrolysis. Calcination at 500 °C for 6 h resulted in the crystallization of the Ce-doped AlOOH gel to form Ce-doped γ-Al(2)O(3) nanowires. Ce(3+) ions within the nanowires were present at a concentration of < 1 at.%. On the template surface, a nanocrystalline CeO(2) thin film was deposited with a cubic fluorite structure and a crystallite size of 6-7 nm. Characterization of the nanowires and thin films was performed using scanning electron microscopy, transmission electron microscopy, electron energy loss spectroscopy, x-ray photoelectron spectroscopy and x-ray diffraction. The nanowire formation mechanism and urea hydrolysis kinetics are discussed in terms of the pH evolution during the reaction. The Ce-doped γ-Al(2)O(3) nanowires are likely to find useful applications in catalysis and this novel method can be exploited further for doping alumina nanowires with other rare earth elements.

Transplantation of umbilical cord mesenchymal stem cells alleviates lupus nephritis in MRL/lpr mice

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease, which, despite the advances in immunosuppressive medical therapies, remains potentially fatal in some patients, especially in treatment-refractory patients. This study found that transplantation of umbilical cord mesenchymal stem cells (UC-MSCs) has the same therapeutic effect as transplantation of bone marrow mesenchymal stem cells (BM-MSCs), which has been reported to be efficient in treating SLE-related symptoms in MRL/lpr mice. Multi-treatment (at the 18th, 19th, and 20th weeks of age) of 1 × 10(6) UC-MSCs was able to decrease the levels of 24-h proteinuria, serum creatinine, and anti-double-stranded DNA (dsDNA) antibody, and the extent of renal injury such as crescent formation in MRL/lpr mice. A lower, but still significant, reduction in these parameters was also observed in mice receiving a single dose of UC-MSCs (at the 18th week). UC-MSCs treatment also inhibited expression of monocyte chemotactic protein-1 (MCP-1) and high-mobility group box 1 (HMGB-1) expression in a similar fashion. UC-MSCs labeled with carboxyfluorescein diacetate succinimidyl ester (CFSE) were found in the lungs and kidneys 1 week post infusion. In addition, after 11 weeks post UC-MSCs infusion, human cells were found in kidney of UC-MSCs-treated mice. These findings indicated that UC-MSCs transplantation might be a potentially promising approach in the treatment of lupus nephritis, possibly by inhibiting MCP-1 and HMGB-1 production.

Detecting positive selection in the budding yeast genome

Available abundant genomic data allows us to study the evolution of the yeast genome at a fine scale. In this study, we examined the adaptive evolution of coding and promoter regions in three Saccharomyces cerevisiae strains. First, using a maximum-likelihood approach, we identified 76 positively selected genes (PSG) whose coding regions likely have undergone positive selection in the recent past. These genes show significant bias in terms of biological function and they show over-representation of charged amino acids at positively selected sites. Next, using recent data on yeast transcription-start sites to define core-promoter regions, we identified 31 positively selected promoters, and their corresponding genes are significantly enriched in transmembrane transporter function. We found PSG show no correlation with promoter adaption or expression variation, suggesting that positive selection on coding regions and positive selection on promoter regions are not coupled. Together, our study provides insights into the evolution of S. cerevisiae strains from different environments.

Impact of hypertension on health-related quality of life in a population-based study in Shanghai, China

OBJECTIVES

The purpose of this study was to examine the relationship between hypertension and health-related quality of life (HRQL) in a general representative Chinese population, and to explore the impacts of comorbidity on people with hypertension.

STUDY DESIGN

Population-based cross-sectional survey.

METHODS

A self-administered questionnaire survey including demographic questions and the Mandarin version of 36-item Short Form (SF-36) was conducted in a general population in Shanghai, China. In total, 1034 subjects participated. The SF-36 dimension scores of hypertensive subjects were compared with those of normotensive subjects. Independent association of hypertension with each quality-of-life domain was analysed using a multiple linear regression model, so were the effects of comorbidity on the HRQL of hypertensive subjects.

RESULTS

Nine hundred and nineteen respondents were included in the analysis, and 16.97% reported hypertension. Respondents with hypertension scored lower than those without hypertension in at least five SF-36 dimensions. The dimension of role limitations due to physical problems was the most affected, whereas the mental health dimension was the least affected. Hypertensive subjects with comorbidity experienced lower SF-36 scores than hypertensive subjects without comorbidity.

CONCLUSIONS

Hypertension markedly impairs quality of life in terms of both physical and mental health. Comorbidity further deteriorates HRQL among people with hypertension. The findings suggest that people with hypertension represent a vulnerable population, and it is important to prevent and treat comorbidity of hypertension.

Growth hormone stimulation of serum insulin concentration in cattle: nutritional dependency and potential mechanisms

Previous studies on the effect of growth hormone (GH) on serum insulin concentration in cattle had generated seemingly conflicting results, and little was known about the mechanism by which GH affects serum insulin concentration in cattle, if it does. In this study, we determined whether the effect of GH on serum insulin concentration in cattle could be affected by the nutritional levels of the animal and whether GH increased serum insulin concentration in cattle by directly stimulating insulin release or insulin gene expression in the pancreatic islets. Administration of recombinant bovine GH increased serum insulin concentration in nonlactating, nonpregnant beef cows fed a daily concentrate meal in addition to ad libitum hay, but it had no effect in those cows fed hay only. Both GH treatments for 1 and 24h increased insulin concentrations in cultures of pancreatic islets isolated from growing cattle. Growth hormone treatment for 24h increased insulin mRNA expression in cultured bovine pancreatic islets. Growth hormone treatment for 16h increased reporter gene expression directed by a approximately 1,500-bp bovine insulin gene promoter in a rat insulin-producing beta cell line. Taken together, these results suggest that exogenous GH can increase serum insulin concentration in cattle, but this effect depends on the nutritional levels of fed cattle, and that GH increases serum insulin concentration in cattle by stimulating both insulin release and insulin gene expression in the pancreatic islets.

Identification and characterization of the bovine G protein-coupled receptor GPR41 and GPR43 genes

Volatile fatty acids (VFA), including acetate, propionate, and butyrate, are not only a primary source of energy, but also regulate rumen development, insulin and glucagon secretion, and other physiological processes in cattle and sheep. The mechanism underlying the regulatory effects of VFA is unknown. Recent "reverse pharmacology" studies identified human G protein-coupled receptors GPR41 and GPR43 as receptors for short-chain fatty acids. It is possible that proteins similar to human GPR41 and GPR43 mediate the regulatory effects of VFA in cattle. In this study, we determined first, whether the bovine genome contains genes similar to the human GPR41 and GPR43 genes; second, whether and where these genes are expressed in cattle; and third, if the proteins encoded by these genes can be activated by acetate, propionate, and butyrate. A search of GenBank revealed bovine genomic sequences and expressed sequence tags highly similar to the human GPR41 and GPR43 DNA and cDNA sequences. The protein-coding and 5' untranslated regions of the bovine GPR41 and GPR43 mRNA were cloned and sequenced from spleen tissue. Based on these sequences, the bovine GPR41 gene contains 3 exons and its transcription is initiated at 2 leader exons, generating 2 GPR41 mRNA variants differing in the 5' untranslated region. The bovine GPR43 gene contains 2 exons and transcription of this gene is initiated from a single start site. The amino acid sequences deduced from the bovine GPR41 and GPR43 mRNA sequences are more than 75% identical to those of the human GPR41 and GPR43 and are predicted to encode 7 transmembrane domains, typical of G protein-coupled receptors. Both bovine GPR41 and GPR43 mRNA were detected in a variety of tissues including rumen and pancreas. In a cell system, interaction of the overexpressed bovine GPR41 or GPR43 protein with acetate, propionate, or butyrate inhibited luciferase reporter expression from a cyclic AMP-responsive promoter, suggesting that the bovine GPR41 and GPR43 proteins couple to Galpha(i/11). In total, these results demonstrate that the bovine genome encodes functional GPR41 and GPR43 genes and suggest that GPR41 and GPR43 may play a role in the regulatory effects of VFA in cattle.

Treatment of cooling tower blowdown water containing silica, calcium and magnesium by electrocoagulation

This research investigated the effectiveness of electrocoagulation using iron and aluminium electrodes for treating cooling tower blowdown (CTB) waters containing dissolved silica (Si(OH)(4)), Ca(2 + ) and Mg(2 + ). The removal of each target species was measured as a function of the coagulant dose in simulated CTB waters with initial pH values of 5, 7, and 9. Experiments were also performed to investigate the effect of antiscaling compounds and coagulation aids on hardness ion removal. Both iron and aluminum electrodes were effective at removing dissolved silica. For coagulant doses < or =3 mM, silica removal was a linear function of the coagulant dose, with 0.4 to 0.5 moles of silica removed per mole of iron or aluminium. Iron electrodes were only 30% as effective at removing Ca(2 + ) and Mg(2 + ) as compared to silica. There was no measurable removal of hardness ions by aluminium electrodes in the absence of organic additives. Phosphonate based antiscaling compounds were uniformly effective at increasing the removal of Ca(2 + ) and Mg(2 + ) by both iron and aluminium electrodes. Cationic and amphoteric polymers used as coagulation aids were also effective at increasing hardness ion removal.

Prevalence of, and factors associated with, gastroesophageal reflux disease: a population-based study in Shanghai, China

The prevalence of gastroesophageal reflux disease (GERD) in China is lower than that in the Western countries, but appears to be increasing. The aim of this pilot study was to evaluate the prevalence of GERD in Shanghai, China, and to explore which population characteristics where associated with GERD. A sample of 1200 adult inhabitants of Shanghai, selected using randomized, stratified, multi-stage sampling, completed Mandarin translations of the Reflux Disease Questionnaire and GERD Impact Scale. Potential risk factors for GERD were examined by nested case-control analysis, using Cochran-Armitage trend testing and logistic regression analysis. The response rate was 86.2%; 919 responses were suitable for analysis. The prevalence of GERD, defined as heartburn and/or regurgitation of any frequency during the previous week, was 6.2% in Shanghai. Obesity and urban dwelling were associated with GERD (odds ratio 3.4, 95% confidence interval 1.3-9.3; and odds ratio 3.6, 95% confidence interval 1.2-10.4, respectively). The prevalence of GERD in Shanghai agreed with previous Chinese studies. GERD in Shanghai was associated with obesity and residency in an urban environment.

Comparison of various blood compartments and reporting units for the detection and quantification of Epstein-Barr virus in peripheral blood

Epstein-Barr virus (EBV) infection is associated with a broad spectrum of disease. While quantification of EBV nucleic acid in the peripheral blood has been demonstrated to be useful for diagnosis and patient care, the optimal sample type and reporting format for such testing remain uncertain. Using quantitative real-time PCR (QRT-PCR), we evaluated EBV in whole blood (WB), peripheral blood mononuclear cells (PBMC), and plasma in 249 samples from 122 patients. In WB and PBMC, results were reported both in viral copies/ml and in copies/microg of total DNA. Trendings of quantitative values over time among the different sample types were compared. The sensitivities of QRT-PCR using WB and that using PBMC did not differ significantly (P = 0.33), and both were more sensitive than plasma alone (P < 0.0001). EBV viral load results from WB and PBMC paired sample types also showed a significant correlation (P < 0.05), as did results reported in copies/ml and copies/microg DNA for both WB and PBMC (R2 > 0.93). EBV viral loads detected using WB and PBMC trended very closely for the few patients who had multiple positive samples available for analysis. WB and PBMC show comparable sensitivities and a close quantitative correlation when assayed for EBV by QRT-PCR. The close correlation between copies/ml and copies/microg DNA also suggests that normalization to cell number or genomic DNA in cellular specimens may not be necessary.

15. RISKS, CHOICES AND CONSEQUENCES: INTERNATIONAL STUDENTS AND SEXUAL HEALTH PROMOTION

International students are the 4th most revenue raising industry in Australia brining in $6 billion in 2006. December 2006 reports show 383 818 international students were enrolled across Australia with 61�019 in Queensland. The vast majority of students come from Asian countries with a high prevalence of HIV/AIDS and STIs combined with minimal sexual health knowledge. Through workshops and discussion groups with international students they have been identified as a high risk in relation to sexual health problems due to their lack of sexual health knowledge, their tendency to engage in risk behaviour without adequate knowledge of risks, consequences and protection mechanisms. As a result, sexual health issues are increasingly presenting to professionals working directly with international students and health services in claims related to pregnancy, abortion rates, sexual assault, rape and reports of international students from high risk countries found to be HIV+. Further, international students reported receiving no information prior to arrival and on arrival of risk behaviour, safety issues, health or laws in Australia. In order to promote safe sex behaviour among international students we have formulated various strategies to raise awareness of international students, from print material on arrival, to information stalls at O-week, intermittent workshops for international students, student leaders and professionals working directly with international students. The feedback from the students is very positive and new strategies are being developed to target students facing language barriers. Our program findings demonstrate that the international student population is a high risk group facing sexual health issues where increased education and support must occur to prevent and reduce sexual health related problems.

In vitro antiretroviral activity and in vitro toxicity profile of SPD754, a new deoxycytidine nucleoside reverse transcriptase inhibitor for treatment of human immunodeficiency virus infection

SPD754 (AVX754) is a deoxycytidine analogue nucleotide reverse transcriptase inhibitor (NRTI) in clinical development. These studies characterized the in vitro activity of SPD754 against NRTI-resistant human immunodeficiency virus type 1 (HIV-1) and non-clade B HIV-1 isolates, its activity in combination with other antiretrovirals, and its potential myelotoxicity and mitochondrial toxicity. SPD754 was tested against 50 clinical HIV-1 isolates (5 wild-type isolates and 45 NRTI-resistant isolates) in MT-4 cells using the Antivirogram assay. SPD754 susceptibility was reduced 1.2- to 2.2-fold against isolates resistant to zidovudine (M41L, T215Y/F, plus a median of three additional nucleoside analogue mutations [NAMs]) and/or lamivudine (M184V) and was reduced 1.3- to 2.8-fold against isolates resistant to abacavir (L74V, Y115F, and M184V plus one other NAM) or stavudine (V75T/M, M41L, T215F/Y, and four other NAMs). Insertions at amino acid position 69 and Q151M mutations (with or without M184V) reduced SPD754 susceptibility 5.2-fold and 14- to 16-fold, respectively (these changes gave values comparable to or less than the corresponding values for zidovudine, lamivudine, abacavir, and didanosine). SPD754 showed similar activity against isolates of group M HIV-1 clades, including A/G, B, C, D, A(E), D/F, F, and H. SPD754 showed additive effects in combination with other NRTIs, tenofovir, nevirapine, or saquinavir. SPD754 had no significant effects on cell viability or mitochondrial DNA in HepG2 or MT-4 cells during 28-day exposure at concentrations up to 200 microM. SPD754 showed a low potential for myelotoxicity against human bone marrow. In vitro, SPD754 retained activity against most NRTI-resistant HIV-1 clinical isolates and showed a low propensity to cause myelotoxicity and mitochondrial toxicity.

Preparation and characterization of EP-liposomes and Span 40-niosomes

Clotrimazole, an imidazole derivative antifungal agent, has been widely used for the treatment of mycotic infections of the genitourinary tract. In order to develop alternative formulations for the vaginal administration of clotrimazole which would provide sustained and controlled release of the appropriate drug for local vaginal therapy, liposomes/niosomes were evaluated as delivery vehicles. To optimize the preparation of the liposomes/niosomes with regard to size and entrapment efficiency, multilamellar liposomes/ niosomes containing the drug were prepared by a lipid hydration method. The liposomes/niosomes thus prepared were evaluated for their stability as drug-loaded liposomes/niosomes in simulated vaginal fluid at 37 +/- 1 degrees C. The two vesicle systems were also evaluated with regard to rat and rabbit vaginal irritation.