Functional Effect of Platelet Membrane Glycoprotein Ia Gene Polymorphism in the Pathogenesis of Unstable Angina Pectoris

The functional effect of platelet membrane glycoprotein Ia ( GPIa) gene 807C/T polymorphism in unstable angina pectoris (UAP) pathogenesis was investigated in Chinese Han individuals. Collagen type I-induced platelet aggregation was measured in 33 healthy subjects. Plasma levels of α-granule membrane protein (GMP-140) were measured in 33 healthy subjects and in 35 patients with recentonset angina at rest within 24 h of hospitalization. Platelet membrane GPIa gene 807C/T polymorphism was determined in all subjects. Lag-time before 30% platelet aggregation was significantly longer in CC genotype than in TC genotype healthy subjects, although there was no significant difference in maximal platelet aggregation between healthy subjects with either genotype. Plasma GMP-140 levels were significantly higher in TC genotype patients compared with CC genotype patients or healthy subjects; a significant difference was also observed between the latter two groups. It was concluded that rapid initiation of collagen-induced platelet aggregation may be associated with the platelet membrane GPIa T807 allele, which may be important in UAP pathogenesis.

Detection of rpoB, katG and inhA gene mutations in Mycobacterium tuberculosis clinical isolates from Chongqing as determined by microarray

The emergence of multidrug-resistance Mycobacterium tuberculosis is an increasing threat to tuberculosis control programmes. Susceptibility testing of Mycobacterium tuberculosis complex isolates by traditional methods requires a minimum of 14 days. This can be reduced significantly if molecular analysis is used. DNA sequencing is a good method for detecting mutation, but cannot be used routinely because of its relatively high cost. A sensitive and specific microarray has been designed to detect mutations in the rifampin resistance determining region of rpoB and loci in katG and inhA associated with isoniazid (INH) resistance. A panel of Mycobacterium tuberculosis isolates containing 13 different rpoB genotypes, two mutation genotypes within codon 315 of katG and one mutation genotypes at inhA was used to validate the microarray. The results obtained indicate that 100% of rifampicin-resistant M. tuberculosis strains isolated in Chongqing had rpoB mutations, with 531-Ser and 526-His being the most common positions substituted. Of the total 50 INH resistant isolates, 82% had a katG315 mutation and 18% had an inhA mutation. All the mutations detected by the microarray method were also confirmed by conventional DNA sequencing. It is demonstrated that the microarray is an efficient, specialized technique and can be used as a rapid method for detecting rifampin and isoniazid resistance.

Porphyromonas gingivalis lipopolysaccharide alters atherosclerotic-related gene expression in oxidized low-density-lipoprotein-induced macrophages and foam cells

BACKGROUND AND OBJECTIVE

The molecular mechanism linking atherosclerosis formation and periodontal pathogens is not clear, although a positive correlation between periodontal infections and cardiovascular diseases has been reported. The aim of this study was to determine whether stimulation with Porphyromonas gingivalis lipopolysaccharide (LPS) affected the expression of atherosclerosis-related genes, during and after the formation of foam cells.

MATERIAL AND METHODS

Macrophages from human THP-1 monocytes were treated with oxidized low-density lipoprotein (oxLDL) to induce the formation of foam cells. P. gingivalis LPS was added to cultures of either oxLDL-induced macrophages or foam cells. The expression of atherosclerosis-related genes was assayed by quantitative real-time PCR, and the production of granulocyte-macrophage colony-stimulating factor, monocyte chemotactic protein-1, interleukin (IL)-1β, IL-10 and IL-12 proteins was determined using ELISA. Nuclear translocation of nuclear factor-kappaB (NF-κB) P(65) was detected by immunocytochemistry, and western blotting was used to evaluate inhibitory kappa B-α (IκΒ-α) degradation to confirm activation of the NF-κB pathway.

RESULTS

P. gingivalis LPS stimulated atherosclerosis-related gene expression in foam cells and increased the oxLDL-induced expression of chemokines, adhesion molecules, growth factors, apoptotic genes and nuclear receptors in macrophages. Transcription of the proinflammatory cytokines IL1β and IL12 was elevated in response to LPS in both macrophages and foam cells, whereas transcription of the anti-inflammatory cytokine, IL10, was not affected. Increased activation of the NF-κB pathway was also observed in macrophages costimulated with LPS + oxLDL.

CONCLUSION

P. gingivalis LPS appears to be an important factor in the development of atherosclerosis by stimulation of atherosclerosis-related gene expression in both macrophages and foam cells via activation of the NF-κB pathway.

High-risk human papillomavirus reduces the expression of microRNA-218 in women with cervical intraepithelial neoplasia

This study was designed to investigate whether there is a correlation between the down-regulation of microRNA-218 (miR-218) and the presence of human papillomavirus (HPV) infection in the pathogenesis of cervical cancer. The participants comprised 78 women with cervical intraepithelial neoplasia (CIN); 22 (28.2%) had CIN 1, 27 (34.6%) had CIN 2 and 29 (37.2%) had CIN 3. MiR-218 expression was determined by reverse transcriptase polymerase chain reaction and HPV genotypes in tissue specimens were identified with a microarray test kit. The findings showed that miR-218 levels in patients with high-risk HPV infection were lower than in those infected with low-risk or intermediate-risk HPV, or in those who were HPV-free. MiR-218 levels in patients with high-risk CIN were lower than in those with low-risk CIN. We concluded that infection with high-risk HPV lowered the expression of miR-218 and that down-regulation of miR-218 was involved in the pathogenesis of cervical cancer.

Novel chimeric thyroid-stimulating hormone-receptor bioassay for thyroid-stimulating immunoglobulins

Thyroid-stimulating immunoglobulins (TSI) are a functional biomarker of Graves' disease (GD). To develop a novel TSI bioassay, a cell line (MC4-CHO-Luc) was bio-engineered to constitutively express a chimeric TSH receptor (TSHR) and constructed with a cyclic adenosine monophosphate (cAMP)-dependent luciferase reporter gene that enables TSI quantification. Data presented as percentage of specimen-to-reference ratio (SRR%) were obtained from 271 patients with various autoimmune and thyroid diseases and 180 controls. Sensitivity of 96% and specificity of 99% for untreated GD were attained by receiver operating characteristic analysis, area under the curve 0·989, 95% confidence interval 0·969-0·999, P = 0·0001. Precision testing of manufactured reagents of high, medium, low and negative SRR% gave a percentage of coefficient-of-variation of 11·5%, 12·8%, 14·5% and 15·7%, respectively. There was no observed interference by haemoglobin, lipids and bilirubin and no non-specific stimulation by various hormones at and above physiological concentrations. TSI levels from GD patients without (SRR% 406 ± 134, mean ± standard deviation) or under anti-thyroid treatment (173 ± 147) were higher (P < 0·0001) compared with TSI levels of patients with Hashimoto's thyroiditis (51 ± 37), autoimmune diseases without GD (24 ± 10), thyroid nodules (30 ± 26) and controls (35 ± 18). The bioassay showed greater sensitivity when compared with anti-TSHR binding assays. In conclusion, the TSI-Mc4 bioassay measures the functional biomarker accurately in GD with a standardized protocol and could improve substantially the diagnosis of autoimmune diseases involving TSHR autoantibodies.

Strong impact of acute kidney injury on survival after liver transplantation

Acute kidney injury (AKI) is a major complication in orthotopic liver transplantation (OLT). In an evaluation of Acute Kidney Injury Network (AKIN) criteria in liver transplanted patients, we retrospectively analyzed the usefulness of these criteria to predict survival of 193 consecutive patients at a single center who underwent primary OLT for clinical parameters and peak AKI. Postoperative AKI according to AKIN occurred in 60.1% of the patients, namely, stages 1, 2, and 3 in 30%, 13% and 17.1% respectively. Using multivariate logistic regression, AKIN stage 1 and 2 AKI were independently associated with the pre-OLT Model for End-Stage Liver Disease (MELD) score and age, while stage 3 AKI was independently associated with MELD and Acute Physiology and Chronic Health Evaluation (APACHE) II scores. The 28-day and 1-year mortality post-OLT of AKI patients were 15.5% and 25.9% respectively compared with 0% and 3.9% among non-AKI patients (P < .05 for both). The survival rates of non-AKI and stages 1, 2, and 3 AKI subjects were 96%, 85.5%, 84%, and 45.3%, respectively. Cox regression analysis showed independent risk factors for mortality during the first year after transplantation to include post-OLT AKI (12.1; P < .05), post-OLT infection (HR 4.7; P < .01), pre-OLT hypertension (HR 4.4; P < .01) hazard ratio [HR] and post-OLT APACHE II ≥10 (HR 3.6; P < .05). We concluded that AKI as defined by the AKIN criteria is a major complication of OLT linked to a poor outcomes. It remains to be evaluated whether aggressive perioperative therapy to prevent AKI can improve survival among OLT patients.

Notch1 and Notch2 have opposite prognostic effects on patients with colorectal cancer

BACKGROUND

Aberrantly activated Notch signaling has been shown to play a key role in carcinogenesis and progression of various human malignancies. In this study, we investigated the expression of Notch1 and Notch2 in colorectal cancer to determine whether they could serve as prognostic predictors.

PATIENTS AND METHODS

The protein expression of Notch1 and Notch2 was examined by immunohistochemistry in 1003 clinical colorectal cancer specimens. Notch1 and Notch2 protein levels were investigated by immunohistochemistry. Statistical analysis was carried out to assess their prognostic value.

RESULTS

Significantly negative correlation between Notch1 and Notch2 was found in colorectal cancer (P < 0.001). Notch1 and Notch2 were proved to be inversely correlated with tumor differentiation, depth of invasion, lymph node metastases, distant metastasis, TNM (tumor-node-metastasis) stage and survival of patients, suggesting opposite function of the two receptors. Notch1 and Notch2 were proved to be adverse independent prognostic predictors (P < 0.001). Moreover, a synergistic effect of positive Notch1 and negative Notch2 coexpression on predicting poor overall survival was proved.

CONCLUSIONS

Notch1 and Notch2 may be independent adverse prognostic predictors for patients with colorectal cancer. These results would contribute to identify more efficient prognostic predictors and therapeutic targets.

Observing and quantifying airflows in the infection control of aerosol- and airborne-transmitted diseases: an overview of approaches

With concerns about the potential for the aerosol and airborne transmission of infectious agents, particularly influenza, more attention is being focused on the effectiveness of infection control procedures to prevent hospital-acquired infections by this route. More recently a number of different techniques have been applied to examine the temporal-spatial information about the airflow patterns and the movement of related, suspended material within this air in a hospital setting. Closer collaboration with engineers has allowed clinical microbiologists, virologists and infection control teams to assess the effectiveness of hospital isolation and ventilation facilities. The characteristics of human respiratory activities have also been investigated using some familiar engineering techniques. Such studies aim to enhance the effectiveness of such preventive measures and have included experiments with human-like mannequins using various tracer gas/particle techniques, real human volunteers with real-time non-invasive Schlieren imaging, numerical modelling using computational fluid dynamics, and small scale physical analogues with water. This article outlines each of these techniques in a non-technical manner, suitable for a clinical readership without specialist airflow or engineering knowledge.

Does bladder urothelial cancer behave differently in young patients?

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Background: From 2000 to 2008, the incidence of bladder urothelial cancer in the young adults was diagnosed at an increasing trend at the Tongji Hospital, China. To investigate whether bladder urothelial cancer in patients under the age of 40 years behaves significantly differently from the bladder urothelial cancer in elder patients.

Methods: From 1994 to 2008, the records of 4,568 patients with pathological diagnosis of bladder urothelial cancer presented to the Tongji Hospital were retrospectively reviewed. 82 patients were younger than 40 at the time of diagnosis. The clinicopathologic parameters were compared between this group and a serial of 164 older patients during the same time period. The Kaplan-Meier and Cox regression analyses were performed for the survival analysis.

Results: 2.05% of patients with pathological diagnosis of bladder urothelial cancer presented to the Tongji Hospital were younger than 40 years (median age 32.93). Compared to the older group, young adults group had a lower sex ratio (male-to-female ratio, 3.4:1vs.6.5:1, p<0.05); much less likely with advanced stages (the percentage of invasive tumor, i.e., T1 or above, 28.1% vs. 52.4%, p<0.01); less with a high grade (the percentage of high grade tumor, 14.6% vs. 22.6%, p<0.05); lower recurrence rate (23.2% vs. 39.6%, p<0.05); less with big tumor size (the percent of tumor size greater than 3 cm, 18.3% vs. 22.0%, p<0.05); and less with multifocal (12.2% vs. 50.6%, p<0.01). Kaplan-Meier method and the log-rank test showed a significantly better cancer specific and overall survival for the group of young patients (p<0.01). The multivariate Cox regression analyses showed the following criteria were independent prognostic factors of overall survival: bladder tumor multiplicity, size greater than 3 cm, T2 or above stage, and high grade.

Conclusions: Despite an increasing trend of diagnosis, both the pathologic features and clinical outcomes were significantly better in the young patients with bladder urothelial cancer when compared to their elderly counterparts. These findings suggested that more consevertive management approaches may be warranted for this group of patients even under the circumstances of extensive bladder involvement.

No significant financial relationships to disclose.

Arterial stiffness and asymptomatic intracranial large arterial stenosis and calcification in hypertensive chinese

BACKGROUND

Intracranial large artery disease (ICLAD), such as stenosis and calcification, is common in Chinese patients with stroke. However, little is known about ICLAD and its association with large arterial stiffness in hypertensive patients.

METHODS

We recruited 270 (mean age 61.0 years, 45.6% male) untreated hypertensive patients without stroke from a community in Shanghai, China. ICLAD was detected by computerized tomographic angiography (CTA). Carotid-femoral pulse wave velocity (cf-PWV), office, and 24-h ambulatory pulse pressure (PP) as well as ambulatory arterial stiffness index (AASI) were determined as the measures of arterial stiffness.

RESULTS

Among all participants, 26 (9.6%) had concurrent intracranial arterial stenosis and calcification, 11 (4.1%) stenosis only, and 71 (26.3%) calcifications only. After adjustment for age, mean arterial pressure, and other covariables, there was significant difference in cf-PWV (13.1 vs. 13.7 vs. 15.0 m/s; P = 0.0015) and 24-h PP (46.7 vs. 48.8 vs. 55.7 mm Hg; P = 0.0007) between patients with normal vessels (n = 162), with stenosis or calcification (n = 82), and with both lesions (n = 26). Multiple ordinal logistic regression analyses showed that both cf-PWV and 24-h PP were independently associated with ICLAD. Odds ratios (95% confidence interval (CI)) of ICLAD after multivariable and mutually adjustment were 1.51 (1.09-2.10) and 1.46 (1.06-2.01) for 1-s.d. increase in cf-PWV and 24-h PP, respectively. No significant association (P ≥ 0.10) with AASI or office PP was observed in multivariable analysis.

CONCLUSION

Increased arterial stiffness was independently associated with ICLAD. cf-PWV and 24-h PP might be useful in identifying those more likely to have ICLAD among hypertensive patients.

The farther from town the lower the blood pressure: report from rural Yunnan province

BACKGROUND

Hypertension (HTN) is a major cause of death in Chinese farmers. Remoteness from population centers may independently affect HTN prevalence and severity.

METHODS

We used random cluster sampling to select 27 villages in Yunnan province, China. Within each village, we randomly selected 50-80 men and women between the ages of 50 and 70 years. A total of 1,177 participants underwent interviews and blood pressure (BP) measurement. We evaluated the relationship between BP and distance of the participants' village from the town and county centers with and without adjustment for covariates.

RESULTS

There was a significant (P < 0.001) inverse relationship between BP and distance from populations centers. For every 10 km from the town center, the mean systolic BP (SBP) in the village decreased by 1.2 mm Hg and the mean diastolic by 0.5 mm Hg. After adjustment for age, gender, ethnicity, body mass index, smoking, and drinking, we found that SBP decreased by 1.8 mm Hg (P = 0.03) and diastolic BP by 1.0 mm Hg (P = 0.02) for every 10 km distance from the town center.

CONCLUSIONS

HTN prevalence and severity are significantly linked to distance from population centers in rural Chinese farmers. The farther a farmer's village is from larger population centers, the greater is the probability that his/her BP will be normal. This relationship is independent of age, gender, ethnicity, body mass index, smoking, and alcohol use. Strategies in addressing HTN in rural regions should take account of this geographic dependence on distance from population centers.

DAB389 EGF for the treatment of superficial urothelial cancer

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Background: Intravesical BCG has remained the standard treatment for superficial bladder cancer for decades, despite frequent recurrences after its use. Toxic fusion proteins are a novel class of agents containing both a targeting and a treatment component; correspondingly, DAB389EGF contains an EGF and a diphtheria element, thereby targeting any cell expressing EGFR. Notably, the normal urothelium has little or no luminal EGFR expression in contrast to urothelial cancers, which frequently overexpress EGFR.

Methods: DAB389EGF was tested in vitro to determine the effect of DAB389EGF on cell viability in culture. Tests of clonogenicity were performed by treating plated cells for 2 hours and following colony counts over 14 days. DAB389EGF was tested in an orthotopic murine model of bladder cancer with implanted HTB9 cells modified to express luciferase. DAB389EGF was administered intravesically via catheterization of the murine bladder and held in place for 2 hours with a temporary suture to close the urethra. Treatments were continued twice weekly for 2 weeks, with DT-GMCSF used as a control.

Results: Treatment with DAB389EGF yielded IC50's ranging from 0.5 to 15.7 ng/ml in 8 tested bladder cancer cell lines, but the IC50 was > 500ng/ml in the EGFR- negative H520 control cell line. A single 2-hour exposure to DAB389EGF (50ng/ml) decreased colony formation in all of the bladder cancer cell lines, with complete suppression in HT1376 and T24 cells. In the animal model, luciferase activity was lost in 5 of 6 mice treated with DAB389EGF, versus 1 of 6 mice treated with control. After the 2 week treatment period, histological assessment of the treated mice was undertaken and was consistent with the luciferase findings. FISH was used to detect human or murine-originated cells in order to confirm the presence or absence of xenograft tissue histologically.

Conclusions: Targeted-toxin fusion proteins represent a novel treatment approach for superficial bladder cancer. By capitalizing on the differential expression of EGFR between cancerous and normal urothelium, DAB389EGF selectively targets bladder cancer cells. Preliminary animal studies support the efficacy and tolerability of this approach with additionally animal work currently underway.

No significant financial relationships to disclose.

An Investigation of Buried Layer Formation by 40keV Oxygen Implantation Into Silicon

Device grade single crystal <100> silicon wafers have been implanted with 40keV oxygen ions over a dose range of 2×1017 to 8×1017/cm2 at a temperature of 5507±10°C. The specimens have been analyzed, both before and after high-temperature annealing at 1320°C for six hours, using SIMS, RBS, and TEM. During implantation a continuous buried SiO2 layer forms when the dose after which the buried SiO2 layer grows primarily toward the surface. After annealing samples implanted with the doses of both 2×1017 and 3×1017/cm2 it was observed that a defective SIMOX like structure was formed. Implanting with a dose of 4×1017/cm2 results in pit formation in the silicon overlayer. For the sample implanted with a higher dose of 5×1017/cm2, a non-continuous poly-crystalline silicon “overlayer” was formed. It would thus appear that when a single step implantation route is chosen, there is a dose (or layer thickness) limit for the production of a thin film SIMOX structure.

Recent Advances in Solid Hydrogen Storage Systems

Hydrogen energy offers great promise as an energy alternative. Hydrogen technologies can reduce and eliminate the release of carbon dioxide from fossil-fuel combustion, the main cause of global warming. One of the main challenges is hydrogen storage. Storing hydrogen in the solid-state hydride form holds a volumetric advantage over compressed and liquid hydrogen states. Solid hydrogen storage systems also have features of low-pressure operation, compactness, safety, tailorable delivery pressure, excellent absorption /desorption kinetics, modular design for easy scalability, and long cycle life.

In this paper, solid hydrogen storage systems (such as portable power canisters, lightweight fiber wrapped vessels, and aluminum tubular vessels, developed by Texaco Ovonic Hydrogen Systems LLC) will be discussed. A system of four canisters each storing approximately 80 grams of reversible hydrogen is shown to run a 1 kW PEM fuel cell for more than 247 minutes at full power. Canisters show no plastic deformation after more than 500 charge/discharge cycles. The measured strain on canister surfaces indicates that DOT stress limits are not exceeded. The canisters are in the early commercialization stage for uninterrupted power supply (UPS) and auxiliary power unit (APU) applications.

A lightweight fiber-wrapped vessel engineered with metal hydride and internal heat exchanger is being developed for onboard applications. At the system level, the vessel has a volumetric energy density of 50 grams of hydrogen per liter and a gravimetric density of 1.6 wt.%. The vessel is capable of storing 3 kg of hydrogen with a fast refueling capability. Ninety percent of the storable hydrogen can be refueled in 10 minutes at 1500 psig. The vessel can easily release the hydrogen at a rate of 350 slpm at 70°C.

Aluminum tubular vessels are being designed and tested for bulk storage and infrastructure applications including stationary power, hydrogen shipment and hydrogen service stations. The tubular vessel dimensions may be designed for specific applications. For example, a tubular vessel 6 inches in diameter and 62 inches in length can store up to 1 kg of hydrogen.

Role of vascular endothelial growth factor in protection of intrahepatic cholangiocytes mediated by hypoxic preconditioning after liver transplantation in rats

OBJECTIVE

To investigate the effect on intrahepatic cholangiocytes mediated by hypoxic preconditioning (HP) after liver transplantation and the role of vascular endothelial growth factor (VEGF).

MATERIALS AND METHODS

This experiment was based on a model of rat orthotopic liver autotransplantation. Sprague-Dawley rats were randomly divided into 3 groups: normal control, autotransplantation (AT), and HP. The HP group was subjected to 8% oxygen atmosphere for 90 minutes before surgery. At 6, 12, 24, and 48 hours after autotransplantation, the rats were killed for testing .Serum total bilirubin, direct bilirubin, and alkaline phosphatase concentrations were determined. The microstructure of cholangiocytes and the ultramicrostructure of cholangioles were determined. Immunohistochemistry was used to detect the expression of VEGF and the proliferation rate of cholangiocytes.

RESULTS

Total bilirubin, direct bilirubin, and alkaline phosphatase concentrations in the AT group increased considerably more than in the HP group during the entire interval (P < .05). Light microscopy demonstrated that the microstructure of cholangiocytes in the AT group was damaged more seriously than in the HP group. At transmission electron microscopy, the ultramicrostructure of cholangioles was changed more obviously than in the HP group. The expression of VEGF on cholangiocytes and the proliferation rate of cholangiocytes were higher in the HP group than in the AT group over the entire experiment (P < .05).

CONCLUSION

Hypoxic preconditioning has a protective effect on cholangiocytes after liver autotransplantation. The mechanism may be related to HP-induced overexpression of VEGF on cholangiocytes.