Effect of argon protection on the biological activity of acid etched titanium surface

OBJECTIVE

As the contamination of implant surface seriously affects the early osseointegration of implants and reduces the survival rate of implants, it has attracted wide attention of researchers. The most oral titanium implants used in current clinical applications are stored in sealed packages. During the process of packaging, storage and usage, the implants inevitably contact air, which results in the surface contamination. As an inert gas, the argon has very inactive chemical properties and is routinely used as a protective gas to cut air pollution. In this study, we investigated whether argon protection can cut air pollution and maintain lasting surface biological activity of titanium implants.

MATERIALS AND METHODS

We prepared sandblasting etched titanium samples under air protection or under argon protection. The samples prepared under air protection were used as the control. With the scanning electron microscopy, the contact angle measurements and the X-ray photoelectron spectroscopy, we examined surface morphology, hydrophilicity, chemical structures and components of the implants prepared under two gas protections. By using beagles as the animal model, we assessed the bone guide of the implants prepared under argon protection and morphological changes of surrounding tissues.

RESULTS

While compared with those implants prepared under air protection, the surface morphology of implants prepared under argon protection did not change, which had preferable hydrophilicity, and there were differences in percentage of surface chemical elements and chemical structure. After 4 weeks, the bone-implant contact (BIC) in argon protection group was twice of the control group and the difference was statistically significant (p < 0.01). The Implant Niuchu experiments also proved that under argon protection, the implants would have good integration with the surrounding bone tissues.

CONCLUSIONS

This study revealed the implants prepared under argon can cut air pollution and have high bone guide property and biological activity.

Subtypes of major depression: latent class analysis in depressed Han Chinese women

BACKGROUND

Despite substantial research, uncertainty remains about the clinical and etiological heterogeneity of major depression (MD). Can meaningful and valid subtypes be identified and would they be stable cross-culturally?

METHOD

Symptoms at their lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾ 30 years, with recurrent DSM-IV MD. Latent class analysis (LCA) was performed in Mplus. RESULTS; Using the nine DSM-IV MD symptomatic A criteria, the 14 disaggregated DSM-IV criteria and all independently assessed depressive symptoms (n = 27), the best LCA model identified respectively three, four and six classes. A severe and non-suicidal class was seen in all solutions, as was a mild/moderate subtype. An atypical class emerged once bidirectional neurovegetative symptoms were included. The non-suicidal class demonstrated low levels of worthlessness/guilt and hopelessness. Patterns of co-morbidity, family history, personality, environmental precipitants, recurrence and body mass index (BMI) differed meaningfully across subtypes, with the atypical class standing out as particularly distinct.

CONCLUSIONS

MD is a clinically complex syndrome with several detectable subtypes with distinct clinical and demographic correlates. Three subtypes were most consistently identified in our analyses: severe, atypical and non-suicidal. Severe and atypical MD have been identified in multiple prior studies in samples of European ethnicity. Our non-suicidal subtype, with low levels of guilt and hopelessness, may represent a pathoplastic variant reflecting Chinese cultural influences.

IL-6 gene promoter polymorphisms and risk of coronary artery disease in a Chinese population

We investigated the relationships between single nucleotide polymorphisms (SNPs) of the interleukin (IL)-6 gene 174 G>C (rs1800795), 572 G>C (rs1800796), and 597 G/A (rs1800797) and coronary artery disease (CAD) risk in a Chinese population. This case-control study recruited 296 CAD patients and 327 controls between January 2009 and May 2012. Genotyping of IL-6 174 G>C (rs1800795), 572 G>C (rs1800796), and 597 G/A (rs1800797) was performed on a 384-well plate format using the Sequenom MassARRAY platform. CAD patients were more likely to be older and male, with a higher body mass index, diabetes, and hypertension, and presented higher triglycerides, and lower total cholesterol, low-density lipoprotein-cholesterol, and high-density lipoprotein-cholesterol. We found that the IL-6 174CC genotype was associated with a significantly increased risk of CAD compared to the wild-type GG genotype in a codominant model [odds ratio (95% confidence interval) = 1.94 (1.13-3.37)], whereas IL-6 174 G>C polymorphisms presented an increased risk of CAD in dominant and recessive models. However, we did not find that the IL-6 572 CC and 597 AA genotypes were correlated with an increased risk of CAD. IL-6 174 G>C rs1800795 was associated with CAD risk in a Chinese population. Further large-scale studies are required to determine whether IL-6 SNPs interact with environmental factors in the development of CAD.

Detection of fetal sex chromosome aneuploidy by massively parallel sequencing of maternal plasma DNA: initial experience in a Chinese hospital

OBJECTIVES

To evaluate the performance of a massively parallel sequencing (MPS)-based test in detecting fetal sex chromosome aneuploidy (SCA) and to present a comprehensive clinical counseling protocol for SCA-positive patients.

METHODS

This was a retrospective study in a large patient cohort of 5950 singleton pregnancies which underwent MPS-based testing as a prenatal screening test for trisomies 21, 18 and 13, with X and Y chromosomes as secondary findings, in Southwest Hospital in China. MPS-based SCA-positive women were offered the choice of knowing whether their SCA results were positive and those who did commenced a two-stage post-test clinical counseling protocol. In Stage 1, general information about SCA was given, and women were given the option of invasive testing for confirmation of findings; in Stage 2, those who had chosen to undergo invasive testing were informed about the specific SCA affecting their fetus and their management options.

RESULTS

Thirty-three cases were classified as SCA-positive by MPS-based testing. After Stage 1 of the two-stage post-test clinical counseling session, 33 (100%) of these pregnant women chose to know the screening test results, and 25 (75.76%) underwent an invasive diagnostic procedure and karyotype analysis, in one of whom karyotyping failed. In thirteen cases, karyotyping confirmed the MPS-based test results (two X0 cases, seven XXX cases, three XXY cases and one XYY case), giving a positive predictive value of 54.17% (13/24 cases confirmed by karyotyping). After post-test clinical counseling session Stage 2, seven women chose to terminate the pregnancy: one X0 case, two XXX cases, the three XXY cases and the single XYY case. Six women decided to continue with pregnancy: one X0 case and five XXX cases.

CONCLUSION

Our study showed the feasibility of clinical application of the MPS-based test in the non-invasive detection of fetal SCA. Together with a two-stage post-test clinical counseling protocol, it leads to a well-informed decision-making procedure.

The structure of the symptoms of major depression: exploratory and confirmatory factor analysis in depressed Han Chinese women

BACKGROUND

The symptoms of major depression (MD) are clinically diverse. Do they form coherent factors that might clarify the underlying nature of this important psychiatric syndrome?

METHOD

Symptoms at lifetime worst depressive episode were assessed at structured psychiatric interview in 6008 women of Han Chinese descent, age ⩾30 years with recurrent DSM-IV MD. Exploratory factor analysis (EFA) and confirmatoryfactor analysis (CFA) were performed in Mplus in random split-half samples.

RESULTS

The preliminary EFA results were consistently supported by the findings from CFA. Analyses of the nine DSM-IV MD symptomatic A criteria revealed two factors loading on: (i) general depressive symptoms; and (ii) guilt/suicidal ideation. Examining 14 disaggregated DSM-IV criteria revealed three factors reflecting: (i) weight/appetite disturbance; (ii) general depressive symptoms; and (iii) sleep disturbance. Using all symptoms (n = 27), we identified five factors that reflected: (i) weight/appetite symptoms; (ii) general retarded depressive symptoms; (iii) atypical vegetative symptoms; (iv) suicidality/hopelessness; and (v) symptoms of agitation and anxiety.

CONCLUSIONS

MD is a clinically complex syndrome with several underlying correlated symptom dimensions. In addition to a general depressive symptom factor, a complete picture must include factors reflecting typical/atypical vegetative symptoms, cognitive symptoms (hopelessness/suicidal ideation), and an agitated symptom factor characterized by anxiety, guilt, helplessness and irritability. Prior cross-cultural studies, factor analyses of MD in Western populations and empirical findings in this sample showing risk factor profiles similar to those seen in Western populations suggest that our results are likely to be broadly representative of the human depressive syndrome.

Changing patterns of basic household consumption in the Inner Mongolian grasslands: a case study of policy-oriented adoptive changes in the use of grasslands

Grassland ecosystems, as the basic natural resources in the Inner Mongolia Autonomous Region, are becoming increasingly sensitive to human intervention, leading to deterioration in fragile ecosystems. The goal of this study was to describe the restoration policy-oriented adoptive changes to basic household consumption patterns of food, fuel, and water, and their spatial distribution by grassland types in the region. Basic household consumption data were collected in the meadow steppe (Hulun Buir), typical steppe (Xilin Gol), and semi-desert steppe (Ordos) ecosystems using structured questionnaires administered to 209 herders and farmers. In 2010, the householders’ intake comprised a low amount of agri-crops, including staple foods, vegetables and fruit with a high amount of meat, which still dominated the patterns of food consumption. However, the number of households preferring this pattern is decreasing and higher amounts of agri-crop and lower amounts of meat consumption pattern is increasing. From 1995 to 2010, fuel consumption patterns changed from being dominated by bio-fuels (dung) to being dominated mainly by electricity and gas. However, bio-fuel remains a major energy source for daily life in the meadow steppe ecosystem. In all three surveyed grassland types, the use of coal, electricity and gas increased from 1995 to 2010. The source of domestic water in all three surveyed areas is from groundwater, with an increasing trend to use tap water from a public supply rather than from privately owned wells.

Cyclin-dependent kinase 1 inhibitor RO3306 promotes mitotic slippage in paclitaxel-treated HepG2 cells

Hepatocellular carcinoma (HCC) is the most common primary liver neoplasm and current systemic chemotherapy are mostly ineffective. Paclitaxel (PTX) has a clinically significant effect on many malignant tumors. Cells treated with PTX undergo reversible mitotic arrest and although high doses can cause side effects it may also induce apoptosis. We investigated the effect of a sequential combination of PTX and RO3306, a cyclin-dependent kinase 1 inhibitor, on the hepatocellular carcinoma HepG2 cell line. The sequential drug treatment protocol involved the addition of PTX (0.2 µmol/L) for 18 h followed by RO3306 (2 µmol/L) for a further 6 h. Cell viability and proliferation were measured using tetrazolium dye (MTT) and colony formation assay. Cell cycle profiles were established by flow cytometry. The expression level of protein was examined by immunoblotting. We observed a synergistic effect of PTX and RO3306 treatment on cell growth and proliferation as well as an increased proportion of cells in sub-G1 phase. Expression levels of cyclin B, cyclin E and phosphorylated Histone H3 demonstrated that RO3306 enhanced apoptosis in PTX treated cells by mitotic slippage. Our data suggested that the combination of PTX and RO3306 may be an effective therapeutic combination for the treatment of liver cancer.

Morphologic characteristics of atherosclerotic middle cerebral arteries on 3T high-resolution MRI

BACKGROUND AND PURPOSE

There are limited studies on the morphologic characteristics of MCA atherosclerotic stenosis. Our aim was to quantitatively assess the remodeling pattern and plaque distribution of atherosclerotic MCAs with 3T high-resolution MR imaging.

MATERIALS AND METHODS

Eighty-seven consecutive patients with symptomatic atherosclerotic stenoses at the M1 segment of the MCA on DSA (50%-99%) were enrolled. The remodeling index was calculated as the Vessel Area at Maximal Lumen Narrowing/Reference Vessel Area. A remodeling index ≥ 1.0 was defined as positive remodeling, and a remodeling index < 1.0, as negative remodeling. Plaque distribution at the maximal lumen narrowing site was classified on the basis of the involvement of the superior, inferior, dorsal, or ventral MCA wall.

RESULTS

Forty-three of 87 patients were excluded due to poor imaging quality (n = 8) or scan plane obliquity secondary to a tortuous M1 segment of the MCA or an MCA ostium lesion or angled lesion (n = 35). Of 44 patients in the final analysis, negative remodeling was found in 19 (43.2%) lesions, and positive remodeling, in 25 (56.8%) lesions. At maximal lumen narrowing sites, lesions with negative remodeling had less vessel area, wall area, and percentage of plaque burden (P < .0001) and a lower eccentricity index (P = .023), compared with lesions with positive remodeling. The plaque involved the superior and dorsal walls in 15 (34.1%) of 44 patients.

CONCLUSIONS

2D high-resolution MR imaging can help assess the remodeling pattern and plaque distribution of MCA stenosis, but the imaging and postprocessing protocol for remodeling assessment needs to be improved in the tortuous course of the MCA and in MCA ostium or angled lesions.

Energy, amino acid, and phosphorus digestibility of phytase transgenic corn for growing pigs

Three experiments were conducted to evaluate energy, AA, and P digestibility in a phytase transgenic corn (PTC) containing a phytase gene (phyA2) isolated from Aspergillus niger compared with a nontransgenic near-isoline conventional corn (CC) grown in the same environmental conditions for growing pigs. Experiment 1 was an energy balance experiment conducted to measure DE and ME in PTC and CC. Eighteen growing barrows (initial BW 25.8±0.3 kg) from 9 litters were allotted by BW and litter to 1 of 2 dietary treatments with 9 pigs per treatment in a randomized complete block design. Pigs were individually placed in metabolism cages and fed diets based on the 2 corns. The DE and ME in PTC (3,967 and 3,941 kcal/kg of DM, respectively) were greater (P<0.05) than those in CC (3,917 and 3,848 kcal/kg of DM, respectively). Experiment 2 was conducted to measure apparent ileal digestibility (AID) and standardized ileal digestibility (SID) values of CP and AA in the 2 corns. Eighteen growing barrows (initial BW 41.8±0.7 kg) were equipped with a T-cannula in the distal ileum. Pigs were placed in metabolism cages in a completely randomized design with 3 dietary treatments of 6 pigs each. An N-free diet was used to estimate basal endogenous losses of CP and AA. The AID and SID values for CP and all AA did not differ between the 2 corns. Experiment 3 was conducted to measure apparent total tract digestibility (ATTD) and standardized total tract digestibility (STTD) values of P in the 2 corns. Eighteen growing pigs (initial BW 30.5±0.5 kg) from 6 litters were placed in metabolism cages in a randomized complete block design with 3 dietary treatments of 6 pigs each based on BW and litter. Two diets were based on the 2 corns, and a P-free diet was used to measure endogenous P losses. The ATTD and STTD values of P were greater (P<0.05) in the PTC diet (71.4% and 76.9%, respectively) than those in the CC diet (27.6% and 33.4%, respectively). Pigs fed the PTC diet had a greater (P<0.05) P retention (70.7%) than those fed the CC diet (27.1%). It was concluded that PTC had a greater digestibility of energy and P than CC for growing pigs. As a consequence, if PTC replaces CC in a pig diet, the DE and ME in the diet will increase, and less inorganic P will need to be supplemented to the diet, and thus P excretion in manure will be decreased.

Evaluation of an isotope dilution liquid chromatography tandem mass spectrometry method for pharmaceuticals in fish

An isotope dilution liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was successfully developed and applied for analysis of 15 pharmaceuticals and 2 pharmaceutically active metabolites in fish tissues. This method relied on electrospray ionization (ESI), for which the influence of sample matrix on analyte ionization efficiencies remains a persistent challenge to environmental analysis. Statistically derived method detection limits (MDLs) for most analytes ranged from 1 to 10 ng/g, independent of sample matrix, and were as low as 0.04 ng/g for the most sensitive compounds in fillet tissue. MDLs for fish fillets were determined for both 10 μL and 100 μL injection volumes; however, results showed that detection limits did not scale linearly with injection volume. Direct comparison of spike recoveries from fish liver demonstrated that isotope dilution was superior to matrix-matched calibration in compensating for matrix interference. Spike recoveries for the isotope dilution approach generally ranged from 91 to 112%, independent of tissue (i.e., fillet or liver). The developed method was applied to examine target analytes in brown trout (Salmo trutta), collected upstream and downstream from a municipal effluent discharge to East Canyon Creek, Park City, UT, USA. Though no pharmaceuticals were detected in fish samples from the upstream location, 3 and 10 compounds (out of 17 target analytes) were detected in fish fillet and liver samples, respectively, from the downstream sampling site. Pharmaceuticals in fish fillets were observed at concentrations ranging from 0.14 to 12 ng/g, while levels were markedly higher in liver tissues (range: 0.27-600 ng/g).

Bacterial communities in sediments of the shallow Lake Dongping in China

AIMS

The purpose of this study was to discuss how the environmental inputs and anthropogenic activities impact bacterial communities in the sediments of a shallow, eutrophic and temperate freshwater lake.

METHODS AND RESULTS

Sediment cores were collected from Lake Dongping, located in Taian, Shandong, China. All samples were processed within 4 h of collection. Total nitrogen, total phosphorus (TP), total organic carbon, ammonium nitrogen and nitrate nitrogen content of samples were measured by Kjeldahl determination, sulphuric acid-perchloric acid digestion and molybdenum blue colorimetry, potassium dichromate titration, Nessler's reagent colorimetric and the phenol disulphonic acid colorimetric method, respectively. Seasonal and temporal diversity of sediment bacterial communities at six stations in Lake Dongping were investigated using molecular approaches (terminal restriction fragment length polymorphism and 16S rDNA clone libraries). Noticeable seasonal and temporal variations were observed in bacterial diversity and composition at all six stations. Sediment bacterial communities in Lake Dongping belonged to 16 phyla: Proteobacteria (including α-Proteobacteria, β-Proteobacteria, δ-Proteobacteria, ε-Proteobacteria, γ-Proteobacteria), Acidobacteria, Planctomycetes, Bacteroidetes, Firmicutes, Verrucomicrobia, Nitrospira, Chloroflexi, Gemmatimonadetes, Chlorobi, Cyanobacteria, Deferribacteres, Actinobacteria, OP8, Spirochaetes and OP11. Members of β-, δ- and γ-Proteobacterial sequences were predominant in 11 of 12 clone libraries derived from sediment samples. Sediment samples collected at stations 1 and 4 in July had the greatest bacterial diversity while those collected at station 2 in October had the least diversity. TP concentration was significantly correlated with the distribution of bacterial communities.

CONCLUSIONS

Our results suggested that different environmental nutrient inputs contribute to seasonal and temporal variations of chemical features and bacterial communities in sediments of Lake Dongping. TP concentration was significantly correlated with the distribution of bacterial communities.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study has an important implication for the optimization of integrated ecosystem assessment of shallow temperate freshwater lake and provides interesting information for the subsequent of the ecosystem.

Purification and characterization of an intracellular beta-glucosidase from the protoplast fusant of Aspergillus oryzae and Aspergillus niger

Protoplasts of Aspergillus oryzae 3.481 and Aspergillus niger 3.316 were prepared using cellulose and snail enzyme with 0.6 M NaCl as osmotic stabilizer. Protoplast fusion has been performed using 35% polyethylene glycol 4.000 with 0.01 mM CaCl2. The fused protoplasts have been regenerated on regeneration medium and fusants were selected for further studies. An intracellular beta-glucosidase (EC 3.2.1.21) was purified from the protoplast fusant of Aspergillus oryzae 3.481 and Aspergillus niger 3.316 and characterized. The enzyme was purified 138.85-fold by ammonium sulphate precipitation, DE-22 ion exchange and Sephadex G-150 gel filtration chromatography with a specific activity of 297.14 U/mg of protein. The molecular mass of the purified enzyme was determined to be about 125 kDa by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The enzyme had an optimum pH of 5.4 and temperature of 65 degrees C, respectively. This enzyme showed relatively high stability against pH and temperature and was stable in the pH range of 3.0-6.6. Na+, K+, Ca2+, Mg2+ and EDTA completely inhibited the enzyme activity at a concentration of 10 mM. The enzyme activity was accelerated by Fe3+. The enzyme activity was strongly inhibited by glucose, the end product ofglucoside hydrolysis. The K(m) and V(max) values against salicin as substrate were 0.035 mM and 1.7215 micromol min(-1), respectively.

Arterial remodeling of advanced basilar atherosclerosis: a 3-tesla MRI study

BACKGROUND

There are limited studies on wall imaging of human basilar artery (BA). Our aim was to investigate remodeling mode of advanced BA atherosclerosis using 3-T MRI.

METHODS

Thirty-two consecutive symptomatic patients with atherosclerotic BA stenosis >or=70% were imaged with a 3-T magnetic resonance scanner. Proton density-weighted (PDW) cross-sectional images with submillimeter voxel size were obtained. The vessel area (VA) and lumen area (LA) at the maximal lumen narrowing (MLN) site and reference site were measured. Intraobserver and interobserver variability was determined by intraclass correlation coefficient (ICC). Wall area (WA) was estimated by VA - LA. Plaque size (PS) was estimated by WA at MLN site--reference WA. Percent plaque burden was calculated as (PS/VA at MLN site) x 100%. Remodeling index (RI) was the ratio of VA at MLN site to reference VA. RI >or=1.05 was defined as positive remodeling (PR) and RI <1.05 as non-PR.

RESULTS

Measurements of cross-sectional BA images were available in 30 of 32 patients. Intraobserver or interobserver variability was small, with ICC ranging from 0.955 to 0.996. The mean RI of the 30 patients was 1.2 +/- 0.4. PR was found in 19 (63.3%) patients and non-PR in 11 (36.7%) patients. Compared with the non-PR group, the PR group had greater PS (15.0 +/- 9.3 mm(2) vs 6.4 +/- 3.9 mm(2), p = 0.007) and greater percent plaque burden (50.5 +/- 9.9% vs 28.5 +/- 12.7%, p < 0.0001).

CONCLUSIONS

3-T high-resolution PDW imaging is a reproducible tool for measuring BA dimensions. In patients with advanced BA atherosclerosis, PR lesions are more frequently observed and contain larger plaques than non-PR lesions.

Wingspan experience at Beijing Tiantan Hospital: new insights into the mechanisms of procedural complication from viewing intraoperative transient ischemic attacks during awake stenting for vertebrobasilar stenosis

BACKGROUND AND AIM

Intracranial vertebrobasilar artery (VBA) stenosis portends a stroke and death rate of 8.5-22.8% annually despite medical therapy. Stenting has emerged as a treatment option but also carries substantial risk. Awake stenting under local anesthesia to minimize major procedural complication was investigated.

METHODS

Between January 2007 and December 2008, 43 of 46 consecutive patients with severe symptomatic intracranial VBA stenosis underwent elective angioplasty assisted with self-expanding Wingspan stent under local anesthesia at our institute. All data were collected prospectively.

RESULTS

All 43 patients tolerated the stenting procedure under local anesthesia well. Forty-two patients (97.7%) were stented successfully. Within 30 days, there were three periprocedural strokes, including thromboembolic infarct, pontine perforator infarct and intracranial hemorrhage, without fatality. In addition, five patients had intraoperative brainstem transient ischemic attacks (TIAs) seconds after the deployment of the stent delivery system across the tortuous VBA. The symptoms and signs included impaired consciousness (n=5), dysarthria (n=3), convulsion (n=2), conjugate horizontal gaze palsy (n=2), nystagmus (n=2) and pinpoint pupils (n=1). There was angiographic evidence of VBA straightening without thromboembolism. The TIAs resolved within minutes of prompt removal of the delivery catheter.

CONCLUSIONS

VBA stenting under local anesthesia is feasible with a 7% periprocedural stroke risk. Awake stenting allows timely detection of intraoperative TIAs. The mechanism of intraoperative TIA appears to be stent delivery system induced VBA straightening and distortion of its vascular tree. A devastating stroke may ensue if the TIA is not detected and distortion of VBA perforators is not reversed promptly.

Do patients with basilar or vertebral artery stenosis have a higher stroke incidence poststenting?

BACKGROUND AND AIM

Posterior circulation stenosis may be a risk factor associated with stroke after intracranial stenting as compared with anterior circulation stenosis. Our aim was to test our hypothesis that there was no difference in clinical outcome poststenting between patients with severe stenosis of the basilar artery (BA) and intracranial vertebral artery (VA).

METHODS

Using the Cox proportional hazards regression model adjusted for prespecified factors (qualifying event, and timing of stenting after the qualifying event), we compared primary endpoint (ischemic stroke in the vertebrobasilar territory, including any stroke or death within 30 days of stenting) between patients with severe symptomatic atherosclerotic BA and VA stenosis who underwent elective stenting in our prospective database. Analysis was by intention-to-treat principle.

RESULTS

Primary endpoint event occurred in 13 (18.8%) of 69 patients with BA stenosis during a mean 23.4 months (9 within 30 days and 4 afterward) and 3 (4.3%) of 70 patients with VA stenosis during a mean 26.4 months (2 within 30 days and 1 afterward). Patients with BA stenosis had a significantly higher risk of the primary endpoint (adjusted HR=4.87, 95% CI 1.37 to 17.29; p=0.014) or any stroke or death within 30 days of stenting (adjusted HR=5.13, 95% CI 1.10 to 23.96; p=0.038) than those with VA stenosis.

CONCLUSION

A significantly higher stroke risk poststenting exists in patients with severe BA stenosis than those with VA stenosis. The discrepancy in clinical outcome after stenting between patients with BA and VA stenosis should be considered in clinical practice and stenting trials.

Hepatitis B virus subgenotype C2 is the most prevalent subgenotype in northeast China

The geographical distribution of hepatitis B virus (HBV) subgenotypes and their clinical implications in patients with acute and chronic hepatitis B in the Heilung-kiang province of northeast China were investigated. Nested PCR and multiplex PCR were performed with genotype-specific primers and with subgenotype-specific primers to identify genotypes and subgenotypes from serum samples of 412 HBV infections including 69 with acute self-limited hepatitis (ASH) and 343 with chronic hepatitis (CH). A total of 361 samples were genotyped and 304 were further subgenotyped. The most common HBV genotype was C (93.63%, 338/361), with subgenotype group C2 (83.73%, 283/338) predominating. Genotype B was also found and subgenotype B2 predominated within this genotype. Out of 69 infected patients with ASH, 48 were identified as genotype C and all belonged to subgenotype C2. Of 343 infected patients with CH, 313 were genotyped and 256 were subgenotyped; amongst these, C2 (91.80%, 235/256), B2 (7.42%, 19/256) and mixed subgenotypes B2 and C2 (0.78%, 2/256) were found. In HBV subgenotype C2 infections, ASH had a higher ratio of women than CH patients. These results show that HBV subgenotypes C2 and B2 were found in Heilung-kiang province of northeast China. In ASH and CH groups, the distributions of subgenotypes were coincident with C2, the predominant subgenotype. Analysis of the association between subgenotype and the outcomes of HBV infection was inconclusive in our study.

Long-term outcome of tandem stenting for stenoses of the intracranial vertebrobasilar artery and vertebral ostium

BACKGROUND AND PURPOSE

Patients with symptomatic atherosclerotic stenosis of the intracranial vertebrobasilar artery (VBA) have a poor prognosis, and those with coexistent intracranial and extracranial stenoses have worse outcomes despite medical therapy. Our aim was to study the long-term outcome of patients with symptomatic atherosclerotic tandem stenoses at the intracranial VBA and the vertebral artery ostium (VAO) after elective stent placement.

MATERIALS AND METHODS

Ten consecutive patients (mean age, 65.3 years) with this condition underwent elective stent placement at our institution between September 2001 and December 2007. Technical success was defined as stent placement of both VAO and intracranial VBA stenoses with complete stent coverage of the lesions, residual stenosis of < or = 30%, and good antegrade blood flow. The study end point was a composite of any stroke or death within 30 days and ischemic stroke in the VBA territory after 30 days.

RESULTS

Technical success was obtained in 9 of 10 patients without any stroke or death within 30 days. During a median follow-up duration of 32 months, 1 patient had a fatal ischemic stroke in the VBA territory at 4 months, and the other 9 patients were free from stroke recurrence. Thus, the annual stroke rate in VBA territory (including any stroke or death within 30 days) was 3.8%.

CONCLUSIONS

This pilot study shows that elective stent placement for patients with symptomatic atherosclerotic tandem stenoses at the intracranial VBA and VAO has an acceptable long-term outcome and may be considered as an alternative to medical therapy.

Isolation and characterization of a new defense gene from soybean

A cDNA clone of a single-copy gene designated SbPRP was isolated and characterized from 2-week-old soybean seedlings. It putatively encodes a bimodular protein similar to developmentally regulated proteins in other plant species. The deduced amino acid sequence consists of 126 amino acids with a distinct proline-rich domain (17 amino acids) and a long hydrophobically cysteine-rich domain (84 amino acids), plus a signal peptide of 25 amino acids in N terminal. SbPRP mRNA transcripts accumulated in an organ specific manner. It can be detected in leaves and epicotyls of soybean seedlings, whereas virtually expression signal of SbPRP was not detected in cotyledons, hypocotyls and roots. Further Northern hybridization suggested that SbPRP steady-state mRNA level accumulated differentially not only in response to salicylic acid, but to the inoculation of soybean mosaic virus Sa strain. Also it was responsive to drought treatment and salt (NaCl) stress. Therefore it is likely that SbPRP functions as a defense gene in soybean.

Experimental demonstration of isotropic negative permeability in a three-dimensional dielectric composite

Isotropic negative permeability resulting from Mie resonance is demonstrated in a three-dimensional (3D) dielectric composite consisting of an array of dielectric cubes. A strong subwavelength magnetic resonance, corresponding to the first Mie resonance, was excited in dielectric cubes by electromagnetic wave. Negative permeability is verified in the magnetic resonance area via microwave measurement and the dispersion properties. The resonance relies on the size and permittivity of the cubes. It is promising for construction of novel isotropic 3D left-handed materials with a simple structure.

Quartz crystal microbalance based on torsional piezoelectric resonators

A quartz crystal microbalance (QCM) is described, which is based on a torsional resonator, rather than a conventional thickness-shear resonator. Typical applications are measurements of film thickness in the coating industry and monitoring of biofouling. The torsional QCM is about a factor of 100 less sensitive than the conventional QCM. On the other hand, it can probe film thicknesses in the range of hundreds of microns, which is impossible with the conventional QCM due to viscoelastic artifacts. Data acquisition and data analysis proceed in analogy to the conventional QCM. An indicator of the material's softness can be extracted from the bandwidth of the resonance. Within the small-load approximation, the frequency shift is independent of whether the sample is applied to the face or to the side of the cylinder. Details of the geometry matter if the viscoelastic properties of the sample are of interest.

Apollo stent for symptomatic atherosclerotic intracranial stenosis: study results

BACKGROUND AND PURPOSE

A recent trial shows an 8.3 per 100-patient-years' ischemic stroke rate in the territory of the intracranial stenotic artery, despite aspirin treatment. Our aim was to prospectively study the feasibility and outcome of a new intracranial balloon-expandable Apollo stent for symptomatic atherosclerotic intracranial stenosis (SAIS).

MATERIALS AND METHODS

Forty-six patients (41 men and 5 women; median, 54 years of age) with forty-eight >or=50% SAISs were enrolled. Procedural feasibility was evaluated by stent success (residual stenosis <or=30%) and procedural time. The primary end point was ischemic stroke in the target-lesion artery territory, including any stroke and death within 30 days.

RESULTS

Forty-four lesions (91.7%) obtained stent success within a median procedural time of 50.6 minutes. Severe tortuosity correlated with stent failure. Three patients (6.5%, 3/46) had minor strokes within 30 days. All patients were available for follow-up (46 had 30-day follow-up, 45 had 6-month follow-up, 44 had 12- and 18-month follow-up, and 24 had follow-up of >or=24 months), which varied from 1 month to 30.7 months (median, 23.9 months). After 30 days, 1 patient (2.2%, 1/46) developed minor stroke in the target-lesion artery territory at 6.7 months. Primary end point rate was 4.3 per 100 patient years. Angiographic follow-up was performed in 25 patients. Seven restenoses (28%, 7/25) were detected, 1 of which was symptomatic.

CONCLUSION

Angioplasty with the Apollo stent for symptomatic atherosclerotic intracranial stenosis is feasible. Severe tortuosity is an independent predictor of stent failure. Our clinical outcome seems to compare favorably with results of aspirin therapy, but the restenotic rate was high.

Long-term outcome of elective stenting for symptomatic intracranial vertebrobasilar stenosis

Seventy-nine consecutive patients with symptomatic atherosclerotic stenosis > or = 50% of intracranial vertebrobasilar artery (VBA) were treated by elective stenting. There were five strokes within 30 days, and three strokes in the VBA territory after 30 days (mean of 812 days). The annual stroke rate in the VBA territory (including any stroke and death within 30 days) was 4.6%. At the last follow-up time, 73 patients were independent (modified Rankin scale grade < or = 2). The outcome compares favorably with medical therapy.

Comparison of elective stenting of severe vs moderate intracranial atherosclerotic stenosis

OBJECTIVE

To test whether symptomatic severe intracranial atherosclerotic stenosis was associated with a higher subsequent stroke risk than moderate stenosis after elective angioplasty with a balloon-expandable stent and to explore which factors were associated with the subsequent stroke.

METHODS

Between September 2001 and June 2005, there were 220 symptomatic intracranial atherosclerotic stenoses in 213 patients undergoing elective stenting at our institute. Of these stenoses, 126 in 121 patients were > or =70% severe stenoses, and 94 in 92 patients were 50% to 69% moderate stenoses. Primary endpoints included lesion-related ischemic stroke, and symptomatic brain or subarachnoid hemorrhage.

RESULTS

Ten primary endpoint events occurred in the severe stenosis group (six within 30 days and four in mean follow-up of 26.0 months after 30 days), and seven occurred in the moderate stenosis group (four within 30 days and three in mean follow-up of 27.6 months after 30 days). There was no significant difference in cumulative probability of primary endpoints between the severe (7.2% at 1 year and 8.2% at 2 years) and moderate (5.3% at 1 year and 8.3% at 2 years) stenosis groups. No single factor was found to be associated with primary endpoints in the moderate stenosis group. Multivariable analysis revealed that stent failure was the only predictor of primary endpoints in the severe stenosis group (hazard ratio 5.31, 95% CI 1.35 to 20.91).

CONCLUSION

Symptomatic severe intracranial atherosclerotic stenosis did not present a higher subsequent stroke risk than moderate stenosis after elective angioplasty with a balloon-expandable stent. Patients with severe stenosis may benefit from successful stent placement, and randomized trials are necessary to demonstrate this possible benefit.

Perforator stroke after elective stenting of symptomatic intracranial stenosis

OBJECTIVE

To study the frequency, clinical course, and functional outcome of perforator stroke (PS) resulting from elective stenting of symptomatic intracranial stenosis.

METHODS

Between September 2001 and November 2004, 169 consecutive patients with 181 symptomatic intracranial stenoses underwent stenting procedure at our institute. The preoperative perforator infarct adjacent to the stenotic segment (PIAS) on MRI was evaluated blindly. Patients who developed PS after stenting were enrolled. Each patient was assessed by an experienced stroke neurologist by neurologic examination and NIH Stroke Scale score every day until discharge and at day 30, and by modified Rankin Scale (mRS) score at the end of the first, third, and sixth month, and then at intervals of 6 months.

RESULTS

PS frequency was 3.0% (5/169 patients). The patients with preoperative PIAS had a higher frequency of PS and PS exacerbation, resulting from intracranial stenting (8.2%, 4/49), vs patients without preoperative PIAS (0.8%, 1/120; p = 0.031). Four PSs occurred during the procedure and one 10 hours after stenting. Four PSs reached the maximum deficit almost at once, and one after 2 hours from onset. All five patients were functionally independent (mRS <or= 1) within 12 months.

CONCLUSION

Patients with preoperative perforator infarct adjacent to the stenotic segment have a higher perforator stroke frequency after elective stenting of intracranial stenosis. Most perforator strokes occur during the procedure and reach the maximum deficit almost immediately. Functional outcomes are relatively good.

Ascites, but Not Hyponatremia, Is Associated With High Intraoperative Transfusion and Vasopressor Requirements During Liver Transplantation

BACKGROUND

We previously demonstrated that patients with high MELD scores required significantly higher volumes of blood transfusion and vasopressor usage during orthotopic liver transplantation (OLT) compared with patients with low MELD scores. Now we investigated whether hyponatremia or ascites were associated with increased transfusion and vasopressor requirements during OLT.

METHODS

Medical records of 192 OLT patients between January 1, 2004, and May 5, 2005, were retrospectively reviewed. Intraoperative transfusion of red blood cells (RBC) or fresh frozen plasma (FFP) and administration of vasopressors were compared.

RESULTS

As expected, patients with high (>30) MELD scores were associated with higher requirements for intraoperative transfusion and vasopressors than those with low (<or=30) MELD scores. Patients with or without hyponatremia (Na+> or <or=130) had similar requirements for transfusion and vasopressors. Patients with ascites had significantly higher requirements for both transfusion and vasopressors compared with those without (16.6+/-9.6 versus 11.8+/-9.0 for RBC; 22.0+/-11.0 versus 16.1+/-11.8 for FFP; and 60.2% versus 37.5% for vasopressors, P=.001 to .002). Patients with high (>30) MELD plus ascites scores (MELD+A, 4.5 points added to MELD if ascites was present) had higher requirements for transfusion and vasopressors compared with patients with low (<or=30) MELD+A scores (16.1+/-9.9 versus 11.4+/-8.6 for RBC; 21.7+/-12.7 versus 15.2+/- 9.6; and 63.4% versus 28.2% for vasopressors, P=.001 to <.001).

CONCLUSION

Although hyponatremia and ascites are indicators for liver disease severity, ascites, but not hyponatremia, is associated with increased intraoperative transfusion and vasopressor requirements during OLT.

Estrogen and raloxifene induce apoptosis by activating p38 mitogen-activated protein kinase cascade in synthetic vascular smooth muscle cells

Proliferation of vascular smooth muscle cells (VSMC) plays a major role as an initiating event of atherosclerosis. Although estrogen directly inhibits the proliferation of VSMC, the mechanism has not been firmly established. In addition, the effect of raloxifene on VSMC remains unknown. 17Beta-estradiol (E(2)) and raloxifene significantly inhibited the growth of VSMC under growth-stimulated conditions. Since mitogen-activated protein (MAP) kinases have been implicated in VSMC proliferation, the role of MAP kinases in both the E(2)- and raloxifene-induced growth inhibition of VSMC was studied. Both E(2) and raloxifene caused rapid, transient phosphorylation and activation of p38 that was not affected by actinomycin D and was blocked by ICI 182,780. In contrast with p38 phosphorylation, extracellular signal-regulated protein kinase (ERK) phosphorylation was significantly inhibited and c-Jun N-terminal kinase (JNK) phosphorylation was not changed by E(2). Because VSMC expressed both estrogen receptor (ER) alpha and ERbeta, it is not known which of them mediates the E(2)-induced phosphorylation of p38. Although E(2) did not affect the p38 phosphorylation in A10 smooth muscle cells, which express ERbeta but not ERalpha, transfection of ERalpha expression vector into A10 cells rendered them susceptible to induction of p38 phosphorylation by E(2). We then examined whether E(2) and raloxifene induce apoptosis through a p38 cascade. Both E(2) and raloxifene induced apoptosis under growth-stimulated conditions. The p38 inhibitor SB 203580 completely blocked the E(2)-induced apoptosis. Our findings suggest that both E(2)- and raloxifene-induced inhibition of VSMC growth is due to induction of apoptosis through a p38 cascade whose activation is mediated by ERalpha via a nongenomic mechanism.

Branched crystal morphology of linear polyethylene crystallized in a two-dimensional diffusion-controlled growth field

The branched crystal morphology of linear polyethylene formed at various temperatures from thin films has been studied by atomic-force microscopy (AFM), transmission electron microscopy (TEM), electron diffraction (ED) pattern and polymer decoration technique. Two types of branched patterns, i.e. dendrite and seaweed patterns, have been visualized. The fractal dimension d(f) = 1.65 of both dendrite and some of seaweed patterns was obtained by using the box-counting method, although most of the seaweed patterns are compact. Selected-area ED patterns indicate that the fold stems tilt about 34.5( degrees ) around the b-axis and polymer decoration patterns show that the chain folding direction and regularity in two (200) regions are quite different from each other. Because of chain tilting, branched crystals show three striking features: 1) the lamella-like branches show two (200) regions with different thickness; 2) the crystals usually bend towards the thin region; 3) the thick region grows faster by developing branches, thus branches usually occur outside the thick region. The branched patterns show a characteristic width w, which gives a linear relationship with the crystallization temperature on a semilogarithmic plot.

[Study of a mutation in connexin 26 gene associated with congenital sensorineural deafness]

OBJECTIVE

So far, at least 39 deafness gene loci have been mapped in human chromosome including the connexin 26 gene coding for a gap-junction protein. This gene is thought to be linked to hereditary non-syndromic sensorineural hearing loss. About 80% of cases of DFNB1 hereditary deafness carry a 30 mer G mutation of connexin 26.

METHOD

To investigate this relationship, we obtained DNA samples from 15 cases with autosomal recessive and autosomal dominant forms of non-syndromic deafness. In addition, DNA samples were obtained from 252 unrelated subjects with sporadic hearing loss; parents of these subjects were symptom free. We analyzed the coding region for the connexin 26 gene for mutation using PCR-SSCP and sequence analysis and PCR-mediated site-directed mutagensis.

RESULT

We detected 46 mutations with SSCP. The PCR products that of 5 cases mutations had similar abnormalities in their electrophoresis bands were sequenced. Results from 2 cases of families with hereditary hearing loss and 3 cases of sporadic hearing loss had a G-to-A transversion at nucleotide 79. In addition, 2 cases sporadic hearing loss with 251 delT and 233 delC were found, 35 delG was not detected in 46 cases abnormal PCR products using PSDM assay.

CONCLUSION

High mutation rates were found in China deafness population of connexin 26 gene, but the mutation loci is different from those previously reported. Finding hot spot of connexin 26 gene mutation in China population is important for deafness etiologic diagnosis and affect genetic counseling.

Syntheses and structural characterizations of sheet- and column-like lanthanide-transition metal arrays: the effect of hydrogen bonding on the structure when K(+) is replaced by [NH4]+

Sheet- and column-like cyanide bridged lanthanide-transition metal arrays were synthesized through metathesis reactions between anhydrous LnCl(3) (Ln = Eu, Yb) and A(2)[M(CN)(4)] (A = K(+), NH(4)(+); M = Ni, Pt) in a 1:2 molar ratio in DMF (DMF = N,N-dimethylformamide) solution. Single-crystal X-ray analysis revealed that complexes of formula [K(DMF)(7)Ln[M(CN)(4)](2)](infinity) (Ln = Eu, M = Ni, 1; Ln = Yb, M = Pt, 2) consist of infinite layers of neutral, puckered sheets that contain hexagonal rings of composition [(DMF)(10)Ln(2)[M(CN)(4)](3)](6) with interstitial (DMF)(4)K(2)[M(CN)(4)] units located between the layers. The sheet structure is generated through the repeating (DMF)(10)Ln(2)[M(CN)(4)](3) unit with trans cyanide ligands in [M(CN)(4)](2)(-) serving as bridges. The column-like complex [(NH(4))(DMF)(4)Yb[Pt(CN)(4)](2)](infinity), 3, is formed when NH(4)(+) replaces K(+). It consists of infinite, negatively charged, square, parallel columns bundled through N-H...NC hydrogen bonds between NH(4)(+) and terminal CN from the columns. Cis cyanide ligands in [Pt(CN)(4)](2)(-) units serve as bridges. Complex 3 is the first known example where Ln(III) centers are coordinated to four [M(CN)(4)](2)(-) units. Bicapped (square face) trigonal prismatic coordination geometries were observed for Ln(III) centers in 1 and 2. Square antiprismatic geometry for Yb(III) centers are observed in 3. Crystal data for 1: triclinic space group P1, a = 8.797(2) A, b = 15.621(3) A, c = 17.973(6) A, alpha = 105.48(2) degrees, beta = 98.60(2) degrees, gamma = 98.15(2) degrees, Z = 2. Crystal data for 2: triclinic space group P1, a = 8.825(1) A, b = 15.673(1) A, c = 17.946(1) A, alpha = 105.46(2) degrees, beta = 99.10(1) degrees, gamma = 98.59(1) degrees, Z = 2. Crystal data for 3: monoclinic space group P2(1)/c, a = 9.032(1) A, b = 29.062(1) A, c = 15.316(1) A, beta = 94.51(1) degrees, Z = 2.

[Study on graft-versus-leukemia effects of donor lymphocyte infusion after nonmyeloablative allogeneic bone marrow transplantation]

OBJECTIVE

To explore the graft-versus-leukemia effects of donor lymphocyte infusion(DLI) after nonmyeloablative allogeneic bone marrow transplantation while attenuating treatment-associated morbidity, mortality and graft-versus-host disease.

METHODS

615(H-2k) mice were loaded with L615 cells and 3 days later received total body irradiation (TBI) 5 Gy (60 Co gamma-ray) followed by allogeneic bone marrow transplantation (allo-BMT). The allo-grafts consisted of 3 x 10(7) bone marrow cells and 1 x 10(7) spleen cells from BALB/c (H-2d) donor mice. Two days after allo-BMT, the recipient mice were given 200 mg/kg of CTX. Afterwards these recipient mice were infused either donor spleen cells (2 x 10(7)) on d14 and d21 or hydrocortison (HC) and cyclosporine A (CsA) treated donor spleen cells (5 x 10(7)) on d14 post-BMT.

RESULTS

Survival time of mice received DLI on d21 and pretreated DLI on d14 post-BMT was longer than that of control group and d14 DLI group(P < 0.01) and without severe graft-versus-host disease.

CONCLUSION

Donor lymphocyte infusion after nonmyeloablative bone marrow transplantation could reduce transplantation-associated morbidity and mortality while strengthening graft-versus-leukemia effects.