Early micromovement of the Articular Surface Replacement (ASR) femoral component: two-year radiostereometry results

Radiostereometric analysis (RSA) can detect early micromovement in unstable implant designs which are likely subsequently to have a high failure rate. In 2010, the Articular Surface Replacement (ASR) was withdrawn because of a high failure rate. In 19 ASR femoral components, the mean micromovement over the first two years after implantation was 0.107 mm (SD 0.513) laterally, 0.055 mm (SD 0.204) distally and 0.150 mm (SD 0.413) anteriorly. The mean backward tilt around the x-axis was -0.08° (SD 1.088), mean internal rotation was 0.165° (SD 0.924) and mean varus tilt 0.238° (SD 0.420). The baseline to two-year varus tilt was statistically significant from zero movement, but there was no significant movement from one year onwards. We conclude that the ASR femoral component achieves initial stability and that early migration is not the mode of failure for this resurfacing arthroplasty.

Associations between Vascular Endothelial Growth Factor Gene Polymorphisms and Susceptibility to Acute Mountain Sickness

Objective:

This study investigated associations between polymorphisms in the vascular endothelial growth factor (VEGF) gene and susceptibility to acute mountain sickness.

Methods:

Two hundred Han Chinese soldiers who developed acute mountain sickness after rapidly ascending to an altitude of < 3600 m and 200 control soldiers (who did not develop the condition) were enrolled in the study. Twelve single nucleotide polymorphisms (SNPs) of the VEGF gene were genotyped in all the study participants. Plasma VEGF concentrations were measured by enzyme-linked immunosorbent assay in 40 subjects with acute mountain sickness and 40 controls before and after exposure to high altitude.

Results:

The frequencies of the rs3025039 genotype and allele were significantly different between the groups. Two SNPs, rs3025039 (which involves a C→T allele variation at position 936 in the 3′ untranslated region) and rs3025030 (which involves a G→C allele variation in the intronic sequence), were associated with a decreased risk of acute mountain sickness.

Conclusion:

The SNPs rs3025039 and rs3025030 of the VEGF gene may be associated with a decreased risk of acute mountain sickness development.

Human papillomavirus type-16 DNA integration in nuclear matrix and chromosome scaffold associated DNA in a cervical-carcinoma cell-line

MARs (matrix attachment region) and SARs (scaffold attachment region) are fragments of DNA that associated with nuclear matrix and chromosome scaffold even after extensive removal of most of the nuclear proteins and chromatin. The present study showed the association of human papillomavirus type 16 DNA with these fragments by polymerase chain reaction in a cervical carcinoma cell line, CC3/CUHK3. This finding proposed an alternative evidence for the elevated transcription rate of the viral genome in transformed cells as nuclear matrix has been proposed to be sites of DNA replication and transcription.

The effect of topiramate plasma concentration on linguistic behavior, verbal recall and working memory

This is the first study of the effect of topiramate on linguistic behavior and verbal recall using a computational linguistics system for automated language and speech analysis to detect and quantify drug-induced changes in speech recorded during discourse-level tasks. Healthy volunteers were administered a single, 100-mg oral dose of topiramate in two double-blind, randomized, placebo-controlled, crossover studies. Subjects' topiramate plasma levels ranged from 0.23 to 2.81 μg/mL. We found a significant association between topiramate levels and impairment on measures of verbal fluency elicited during a picture description task, correct number of words recalled on a paragraph recall test, and reaction time recorded during a working memory task. Using the tools of clinical pharmacology and computational linguistics, we elucidated the relationship between the determinants of a drug's disposition as reflected in plasma concentrations and their impact on cognitive functioning as reflected in spoken language discourse.

The radiation dose-regulated AND gate genetic circuit, a novel targeted and real-time monitoring strategy for cancer gene therapy

The AND gate functions such that when all inputs are activated the downstream gene will be transcribed and it is off otherwise. To accomplish optimal and targeted gene therapy in solid tumor patients, we have constructed an AND gate genetic circuit and investigated whether it could be activated by low-dose radiation in vitro and in vivo. The enhancement green fluorescent protein (EGFP) expression in different tumor cells transfected with control vector plxsn-EGFP confirmed that 2 Gy of radiation and 1% O(2) for 3 h could activate our AND gate. Besides, the obvious different levels of EGFP expression between 2 and 6 Gy of radiation demonstrated that the AND gate could be regulated by radiation doses. Additionally, through EGFP expression and the codistribution of p53 and HIF-1α in xenografts, we illustrated the targeted activation property of the AND gate and real-time monitoring to hypoxic districts in vivo. Moreover, significant growth inhibition and cell cycle arrest in vitro and apoptosis-inducing effects in vitro and in vivo proved that the AND gate induced ideal antitumor effects. In conclusion, the radiation dose-regulated AND gate genetic circuit could not only effectively monitor the therapeutic process in real-time but also induce ideal antitumor efficacy, and can be further exploited for personal therapy in clinical tumor patients.

Cell permeability, migration, and reactive oxygen species induced by multiwalled carbon nanotubes in human microvascular endothelial cells

Multiwalled carbon nanotubes (MWCNT) have elicited great interest in biomedical applications due to their extraordinary physical, chemical, and optical properties. Intravenous administration of MWCNT-based medical imaging agents and drugs in animal models was utilized. However, the potential harmful health effects of MWCNT administration in humans have not yet been elucidated. Furthermore, to date, there are no apparent reports regarding the precise mechanisms of translocation of MWCNT into target tissues and organs from blood circulation. This study demonstrates that exposure to MWCNT leads to an increase in cell permeability in human microvascular endothelial cells (HMVEC). The results obtained from this study also showed that the MWCNT-induced rise in endothelial permeability is mediated by reactive oxygen species (ROS) production and actin filament remodeling. In addition, it was found that MWCNT promoted cell migration in HMVEC. Mechanistically, MWCNT exposure elevated the levels of monocyte chemoattractant protein-1 (MCP-1) and intercellular adhesion molecule 1 (ICAM-1) in HMVEC. Taken together, these results provide new insights into the bioreactivity of MWCNT, which may have implications in the biomedical application of MWCNT in vascular targeting, imaging, and drug delivery. The results generated from this study also elucidate the potential adverse effects of MWCNT exposure on humans at the cellular level.

Cell permeability, migration, and reactive oxygen species induced by multiwalled carbon nanotubes in human microvascular endothelial cells

Multiwalled carbon nanotubes (MWCNT) have elicited great interest in biomedical applications due to their extraordinary physical, chemical, and optical properties. Intravenous administration of MWCNT-based medical imaging agents and drugs in animal models was utilized. However, the potential harmful health effects of MWCNT administration in humans have not yet been elucidated. Furthermore, to date, there are no apparent reports regarding the precise mechanisms of translocation of MWCNT into target tissues and organs from blood circulation. This study demonstrates that exposure to MWCNT leads to an increase in cell permeability in human microvascular endothelial cells (HMVEC). The results obtained from this study also showed that the MWCNT-induced rise in endothelial permeability is mediated by reactive oxygen species (ROS) production and actin filament remodeling. In addition, it was found that MWCNT promoted cell migration in HMVEC. Mechanistically, MWCNT exposure elevated the levels of monocyte chemoattractant protein-1 (MCP-1) and intercellular adhesion molecule 1 (ICAM-1) in HMVEC. Taken together, these results provide new insights into the bioreactivity of MWCNT, which may have implications in the biomedical application of MWCNT in vascular targeting, imaging, and drug delivery. The results generated from this study also elucidate the potential adverse effects of MWCNT exposure on humans at the cellular level.

Multi-walled carbon nanotube-induced gene expression in the mouse lung: association with lung pathology

Due to the fibrous shape and durability of multi-walled carbon nanotubes (MWCNT), concerns regarding their potential for producing environmental and human health risks, including carcinogenesis, have been raised. This study sought to investigate how previously identified lung cancer prognostic biomarkers and the related cancer signaling pathways are affected in the mouse lung following pharyngeal aspiration of well-dispersed MWCNT. A total of 63 identified lung cancer prognostic biomarker genes and major signaling biomarker genes were analyzed in mouse lungs (n=80) exposed to 0, 10, 20, 40, or 80μg of MWCNT by pharyngeal aspiration at 7 and 56days post-exposure using quantitative PCR assays. At 7 and 56days post-exposure, a set of 7 genes and a set of 11 genes, respectively, showed differential expression in the lungs of mice exposed to MWCNT vs. the control group. Additionally, these significant genes could separate the control group from the treated group over the time series in a hierarchical gene clustering analysis. Furthermore, 4 genes from these two sets of significant genes, coiled-coil domain containing-99 (Ccdc99), muscle segment homeobox gene-2 (Msx2), nitric oxide synthase-2 (Nos2), and wingless-type inhibitory factor-1 (Wif1), showed significant mRNA expression perturbations at both time points. It was also found that the expression changes of these 4 overlapping genes at 7days post-exposure were attenuated at 56days post-exposure. Ingenuity Pathway Analysis (IPA) found that several carcinogenic-related signaling pathways and carcinogenesis itself were associated with both the 7 and 11 gene signatures. Taken together, this study identifies that MWCNT exposure affects a subset of lung cancer biomarkers in mouse lungs.

Mechanical strength of ceramic scaffolds reinforced with biopolymers is comparable to that of human bone

Eight groups of calcium-phosphate scaffolds for bone implantation were prepared of which seven were reinforced with biopolymers, poly lactic acid (PLA) or hyaluronic acid in different concentrations in order to increase the mechanical strength, without significantly impairing the microarchitecture. Controls were un-reinforced calcium-phosphate scaffolds. Microarchitectural properties were quantified using micro-CT scanning. Mechanical properties were evaluated by destructive compression testing. Results showed that adding 10 or 15% PLA to the scaffold significantly increased the mechanical strength. The increase in mechanical strength was seen as a result of increased scaffold thickness and changes to plate-like structure. However, the porosity was significantly lowered as a consequence of adding 15% PLA, whereas adding 10% PLA had no significant effect on porosity. Hyaluronic acid had no significant effect on mechanical strength. The novel composite scaffold is comparable to that of human bone which may be suitable for transplantation in specific weight-bearing situations, such as long bone repair.

Ultra-low exposure to α-7 nicotinic acetylcholine receptor partial agonists elicits an improvement in cognition that corresponds with an increase in α-7 receptor expression in rodents: implications for low dose clinical efficacy

Αlpha-7 neuronal nicotinic receptors (NNRs) are considered targets for cognitive enhancement in schizophrenia and Alzheimer's disease. AZD0328 is an alpha-7 NNR partial agonist that enhances cognition in rodents and nonhuman primates at sub-microgram to microgram doses. We hypothesized that increased expression of the alpha-7 receptor contributes to this beneficial activity at low doses and tested this by examining the effect of AZD0328 using in vivo and ex vivo binding, RT-PCR and cognitive function in rodents. AZD0328 (0.00178 mg/kg) was subcutaneously administered to mice 4, 24, 48 and 72 hours prior to testing in novel object recognition and produced a significant increase in cognition at 4, 24 and 48 h post-dosing. In vivo binding was examined in rat brain using [(3)H]AZ11637326 and there was a dose-dependent reduction in receptor binding at higher doses of AZD0328 (0.001-3 mg/kg), and a second alpha-7 partial agonist, SSR180711 (0.01-30 mg/kg). Lower doses of both compounds (0.0001 mg/kg) produced a significant increase in binding of [(3)H]AZ11637326. Ex vivo binding using [(125)I]-α-bungarotoxin, showed a significant increase in receptor number (B(max.)) in the frontal cortex or hippocampus with no significant effect on receptor affinity (K(d)) 2 h post administration of AZD0328. [(3)H]AZ11637326 administered 1.5 h following AZD0328 produced a significant increase in specific binding in rat brain regions. We found that the effect on receptor number was long-lasting, with [(125)I]-α-bungarotoxin binding increased in rats given AZD0328 for 2-48 h, but this was not accompanied by increased mRNA synthesis. SSR180711 produced a similar increase in B(max.) and specific binding with no effect on K(d). Therefore, trace dose of alpha-7 partial agonists has rapid onset and produces a profound, sustained effect on novel object recognition in mice that corresponds by dose to an increase in receptor number in rat brain. These findings provide an explanation for the acute and sustained benefit of alpha-7 receptor activation in working memory in nonhuman primates and guidance for drug development initiatives and treatment regimens for nicotinic partial agonists.

Cancer targeting Gene-Viro-Therapy of liver carcinoma by dual-regulated oncolytic adenovirus armed with TRAIL gene

Liver cancer is a common and aggressive malignancy, but available treatment approaches remain suboptimal. Cancer targeting Gene-Viro-Therapy (CTGVT) has shown excellent anti-tumor effects in a preclinical study. CTGVT takes advantage of both gene therapy and virotherapy by incorporating an anti-tumor gene into an oncolytic virus vector. Potent anti-tumor activity is achieved by virus replication and exogenous expression of the anti-tumor gene. A dual-regulated oncolytic adenoviral vector designated Ad·AFP·E1A·E1B (Δ55) (Ad·AFP·D55 for short thereafter) was constructed by replacing the native viral E1A promoter with the simian virus 40 enhancer/α-fetoprotein (AFP) composite promoter (AFPep) based on an E1B-55K-deleted construct, ZD55. Ad·AFP·D55 showed specific replication and cytotoxicity in AFP-positive hepatoma cells. It also showed enhanced safety in normal cells when compared with the mono-regulated vector ZD55. To improve the anti-hepatoma activities of the virus, the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) gene was introduced into Ad·AFP·D55. Ad·AFP·D55-TRAIL exhibited remarkable anti-tumor activities in vitro and in vivo. Treatment with Ad·AFP·D55-TRAIL can induce both autophagy owing to the Ad·AFP·D55 vector and caspase-dependent apoptosis owing to the TRAIL protein. Therefore, Ad·AFP·D55-TRAIL could be a potential anti-hepatoma agent with anti-tumor activities due to AFP-specific replication and TRAIL-induced apoptosis.

First Report of Impatiens necrotic spot virus in Gentiana macrophylla in China

Large leaf gentian, Gentiana macrophylla Pall., known as Qin Jiao in Chinese, is a medicinal herb. Its root is most commonly used in Chinese traditional medicine to relieve rheumatic conditions and to remove damp-heat. During a survey in July 2009, large leaf gentian plants exhibiting foliar chlorotic and necrotic spots as well as severe stunting were collected in Lijiang County, Yunnan Province of China. Incidence of symptomatic plants ranged from 10 to 30% in the field. Symptomatic leaves from five different G. macrophylla plants were collected and tested for Impatiens necrotic spot virus (INSV), Tomato spotted wilt virus, Watermelon silver mottle virus, Groundnut bud necrosis virus, Tomato chlorotic spot virus, and Groundnut ringspot virus by double-antibody sandwich-ELISA kits (Agdia Inc., Elkhart, IN). All tested samples were positive only for INSV. To further confirm the presence of INSV, reverse transcription (RT)-PCR was conducted. Total RNA was extracted from the symptomatic large leaf gentian plants leaves with a RNeasy Plant Kit (Qiagen Inc., Valencia, CA) and used as a template in RT-PCR using forward (5'-CTT TGC TTT TTA GAA CTG TGC A-3') and reverse (5'-AGA GCA ATT GTG TCA CGA ATA T-3') primers specific to the partial INSV nucleoprotein (N) gene (GenBank No. DQ425096). Amplicons of the expected size (approximately 760 bp) were obtained from all ELISA-positive samples. Three clones were sequenced and the partial nucleocapsid protein genes consensus sequences of these isolates were determined (GenBank No. HQ317133). Nucleotide sequences of large leaf gentian isolates shared 98 to 99% nucleotide identity with INSV sequences of isolates from China, Italy, Japan, United States, and the Netherlands (GenBank Nos. FN400772, GQ336989, DQ425096, AB109100, D00914, AB109100, and X66972). INSV is one of the most serious viral pathogens of ornamental plants in North America, Europe, and Asia (1-3). To our knowledge, this is the first report of natural occurrence of INSV in G. macrophylla in China. References: (1) S. T. Koike. Plant Dis. 92:1248, 2008. (2) E. K. Tóth et al. Plant Dis. 91:331, 2007. (3) Q. Zhang et al. Plant Dis. 94:915, 2010.

Occurrence of Chilli veinal mottle virus in Nicotiana tabacum in Yunnan, China

Flue-cured tobacco (Nicotiana tabacum) is an important crop in Yunnan Province, China. During a survey in July 2010, tobacco plants (N. tabacum cv. Yunyan 85) in the fields near Dali County in the northwest Yunnan Province of China had symptoms of chlorosis along leaf veins and later showed symptoms of white or brown necrosis along the veins. In 10 surveyed fields in Baizhishu Village in the city of Weishan, a commercial tobacco field (10 ha) developed virus-like disease symptoms; the incidence of affected plants ranged from 0.5 to 3%, which caused obvious economic losses. An isolate (YN75) was collected at random from five symptomatic leaves sampled from five plants. Negative staining of crude extracts of the infected leaves and subsequent electron microscopy revealed flexuous rods of 12 to 13 × 750 nm. Pinwheel-like inclusion bodies were abundant in thin sections of infected leaves. The particle size suggested a species of Potyviridae. Thus, the isolate was assayed in double antibody sandwich-ELISA (Agdia, Elkhart, IN) for the presence of Potato virus Y, Tobacco etch virus, and Tobacco vein mottling virus. All antigens gave negative results. Total RNA was extracted from leaves and tested by reverse transcription (RT)-PCR. The primer M4-T (5'-GTT TTC CCA GTC ACG ACT TTT TTT TTT TTT TT-3') was employed for cDNA synthesis described by Chen et al (1). The primer set ChiVMV-F (5'-TAG TTG YGC ATA C (C/G) C AGG AGA GAG-3')/M4 (5'-GTT TTC CCA GTC ACG AC-3') is complimentary to the region of coat protein and 3'-untranslated region of Chilli veinal mottle virus (ChiVMV), respectively. The expected 1,189-bp fragments were amplified from RNA templates and the amplicon was cloned and sequenced (GenBank Accession No. HQ218936). Comparisons of amplicons with the amino acid sequence available in the NCBI database using BLAST showed 91.4% identity with ChiVMV from India (GenBank Accession No. EF213688) and 90.7% with ChiVMV from Taiwan (Accession No. DQ854950). The virus particle size, RT-PCR results, and sequence data revealed that these tobacco plants were infected by ChiVMV. To our knowledge, this is the first report of ChiVMV infecting N. tabacum in China. Reference: (1) J. Chen et al. Arch. Virol. 146:757, 2001.

Comparative serum proteomic analysis of patients with acute-on-chronic liver failure: alpha-1-acid glycoprotein maybe a candidate marker for prognosis of hepatitis B virus infection

The acute-on-chronic liver failure (AoCLF) caused by hepatitis B virus (HBV) infection remains to be a challenge in clinics with a high mortality rate in China, and it is important to identify biomarkers to foresee the prognosis of patients with HBV. The current study analysed serum proteome changes of acute-on-chronic liver failure as a result of acute exacerbation of chronic hepatitis B infection. Serum samples were collected from normal subjects (NS, n = 8), patients with chronic hepatitis B (CHB, n = 12) and patients with AoCLF (n = 12). After removal of albumin/IgG and ultramembrane centrifugation, serum proteins were separated by two-dimensional gel electrophoresis. Differentially expressed spots were identified by matrix-associated laser desorption ionization time-of-flight tandem mass spectrometry. Through the removal of albumin/IgG and ultramembrane centrifugation, the well-resolved and reproducible two-dimensional gel electrophoresis (2-DE) profiles were obtained. A total of 23 proteins were identified on 2-DE profiles by their differential expression between the three cohorts. Mass spectrometry analysis resulted in the identification of 12 proteins unambiguously. Western blot analysis confirmed the proteomics results that the α1-acid glycoprotein (α1-AGP) levels decrease significantly in plasma of patients with AoCLF, but somewhat decreased in patients with chronic HBV. Further α1-AGP levels in bulk serum samples were measured by immune turbidimetry including normal subjects group (n = 25), acute hepatitis group (n = 36), chronic hepatitis group (n = 52) and AoCLF group (n = 48), the level of α1-AGP in AoCLF groups sharply decrease than other groups. Our study shows that α1-AGP may be a potential plasma biomarker for AoCLF diagnosis because of acute exacerbation of chronic hepatitis B infection.

Two-fold elevation of expression of FoxM1 transcription factor in mouse embryonic fibroblasts enhances cell cycle checkpoint activity by stimulating p21 and Chk1 transcription

OBJECTIVES

Forkhead Box M1 (FoxM1) transcription factor regulates expression of cell cycle effective genes and is stabilized by checkpoint kinase 2 (Chk2) to stimulate expression of DNA repair enzymes in response to DNA damage. This study intended to test whether FoxM1 is involved in cell cycle checkpoint pathways.

MATERIALS AND METHODS

Analysis of senescence and cell proliferation in FoxM1 transgenic (TG) mouse embryonic fibroblasts (MEFs) with 2-fold elevation of FoxM1, and overexpression or knockdown of FoxM1 in an inducible FoxM1 expression cell line, or FoxM1 siRNA. Chromatin immunoprecipitation (ChIP), electrophoretic mobility shift assays (EMSA), and cotransfection to determine FoxM1 transcription targets, as well as RNase protection assays and western blot analysis, were performed.

RESULTS

Two-fold elevation of FoxM1 in FoxM1-TG-MEFs resulted in low levels of cell proliferation and increase in permanent cell cycle arrest at early passages (from passage 6 to 9). These phenotypes correlated with increased phosphorylation of p53 on Ser15, elevated expression of cell cycle inhibitor p21 and Chk1 at passage 3. FoxM1 was stabilized in response to DNA damage in MEFs and FoxM1 overexpression induced p21. Knockdown of FoxM1 resulted in decrease in Chk1. ChIP, EMSA and cotransfection assays confirmed that FoxM1 stimulated promoters of p21 and Chk1.

CONCLUSIONS

Chk1 and p21 are direct transcription targets of FoxM1 and FoxM1 participates in transcriptional responses to stress in normal cells.

Diagnosis and microsurgery of symptomatic spontaneous spinal epidural hematoma

BACKGROUND

Symptomatic spontaneous spinal epidural hematoma (SSEH) is an uncommon cause of cord compression that needs emergent treatment. Without effective management of the symptomatic SSEH, irreversible severe spinal injury would be possible.

OBJECTIVES

We aimed to investigate the diagnosis and surgical management of symptomatic SSEH.

METHODS

Five cases of symptomatic SSEH with favorable neurological recovery after emergent microsurgery were prospectively analysed.

RESULTS

The main clinical presentations were root pain and palsy. The main manifestations of MRI were long-segment epidural lesions of high intensity on T1- and T2-weighted images without enhancement. Laminectomy via posterior approach and hematoma removal were undergone for all patients. All patients achieved full neurological recovery without complications.

CONCLUSIONS

MRI manifestation assisted with the main clinical symptoms may aid the preoperative diagnosis of SSEH, and the delay in obtaining preoperative Digital subtraction angiography is worthwhile, especially for those with progressive neurological deterioration.