Biomechanical Research of Three Parallel Cannulated Compression Screws in Oblique Triangle Configuration for Fixation of Femoral Neck Unstable Fractures

OBJECTIVE

Surgical treatment with internal fixation, specifically percutaneous fixation with three cannulated compression screws (CCSs), is the preferred choice for young and middle-aged patients. The mechanical advantage of the optimal spatial configuration with three screws provides maximum dispersion and cortical support. We suspect that the spatial proportion of the oblique triangle configuration (OTC) in the cross-section of the femoral neck isthmus (FNI) may significantly improve shear and fatigue resistance of the fixed structure, thereby stabilizing the internal fixation system in femoral neck fracture (FNF). This study aims to explore the mechanical features of OTC and provide a mechanical basis for its clinical application.

METHODS

Twenty Sawbone femurs were prepared as Pauwels type III FNF models and divided equally into two fixation groups: OTC and inverted equilateral triangle configuration (IETC). Three 7.3 mm diameter cannulated compression screws (CCSs) were used for fixation. The specimens of FNF after screw internal fixation were subjected to static loading and cyclic loading tests, respectively, with five specimens for each test. Axial stiffness, 5 mm failure load, ultimate load, shear displacement, and frontal rotational angle of two fragments were evaluated. In the cyclic loading test, the load sizes were 700 N, 1400 N, and 2100 N, respectively, and the fracture end displacement was recorded. Results were presented as means ± SD. Data with normal distributions were compared by the Student's t test.

RESULTS

In the static loading test, the axial stiffness, ultimate load, shear displacement, and frontal rotational angle of two fragments were (738.64 vs. 620.74) N/mm, (2957.61 vs. 2643.06) N, (4.67 vs. 5.39) mm, and (4.01 vs. 5.52)° (p < 0.05), respectively. Comparison between the femoral head displacement after 10,000 cycles of 700N cyclic loading and total displacement after 20,000 cycles of 700-1400N cyclic loading showed the OTC group was less than the IETC group (p < 0.05). A comparison of femoral head displacement after 10,000 cycles of 1400N and 2100N cycles and total displacement after 30,000 cycles of 700-2100N cycles showed the OTC group was less than another group, but the difference was not significant (p > 0.05).

CONCLUSION

When three CCSs are inserted in parallel to fix FNF, the OTC of three screws has obvious biomechanical advantages, especially in shear resistance and early postoperative weight-bearing, which provides a mechanical basis for clinical selection of ideal spatial configuration for unstable FNF.

[Horizontal sound localization in presence of noise in normal-hearing young adults]

Objective: This study investigates the effect of signal-to-noise ratio (SNR), frequency, and bandwidth on horizontal sound localization accuracy in normal-hearing young adults. Methods: From August 2022 to December 2022, a total of 20 normal-hearing young adults, including 7 males and 13 females, with an age range of 20 to 35 years and a mean age of 25.4 years, were selected to participate in horizontal azimuth recognition tests under both quiet and noisy conditions. Six narrowband filtered noise stimuli were used with central frequencies (CF) of 250, 2 000, and 4 000 Hz and bandwidths of 1/6 and 1 octave. Continuous broadband white noise was used as the background masker, and the signal-to-noise ratio (SNR) was 0, -3, and -12 dB. The root-mean-square error (RMS error) was used to measure sound localization accuracy, with smaller values indicating higher accuracy. Friedman test was used to compare the effects of SNR and CF on sound localization accuracy, and Wilcoxon signed-rank test was used to compare the impact of the two bandwidths on sound localization accuracy in noise. Results: In a quiet environment, the RMS error in horizontal azimuth in normal-hearing young adults ranged from 4.3 to 8.1 degrees. Sound localization accuracy decreased with decreasing SNR: at 0 dB SNR (range: 5.3-12.9 degrees), the difference from the quiet condition was not significant (P>0.05); however, at -3 dB (range: 7.3-16.8 degrees) and -12 dB SNR (range: 9.4-41.2 degrees), sound localization accuracy significantly decreased compared to the quiet condition (all P<0.01). Under noisy conditions, there were differences in sound localization accuracy among stimuli with different frequencies and bandwidths, with higher frequencies performing the worst, followed by middle frequencies, and lower frequencies performing the best, with significant differences (all P<0.01). Sound localization accuracy for 1/6 octave stimuli was more susceptible to noise interference than 1 octave stimuli (all P<0.01). Conclusions: The ability of normal-hearing young adults to localize sound in the horizontal plane in the presence of noise is influenced by SNR, CF, and bandwidth. Noise with SNRs of ≥-3 dB can lead to decreased accuracy in narrowband sound localization. Higher CF signals and narrower bandwidths are more susceptible to noise interference.

Post-procedure anticoagulation in patients with acute ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

Background

Post-procedural anticoagulation (PPAC) after primary percutaneous coronary intervention (pPCI) in patient with ST-segment elevation myocardial infarction (STEMI) may prevent recurrent ischemic events but may increase the risk of bleeding. No consensus has been reached on PPAC use.

Methods

Using data from the CCC-ACS registry, conducted between 2014 and 2019, we stratified all STEMI patients who underwent pPCI according to the use of PPAC or not. Inverse probability of treatment weighting (IPTW) and Cox proportional hazards model with hospital as random effect were used to analyze differences in in-hospital clinical outcomes: the primary efficacy endpoint was mortality, and the primary safety endpoint was major bleeding.

Results

Of 34,826 evaluable patients 26,272 (75.4%) were treated with PPAC, and were on average younger, more stable at admission with lower bleeding risk score, more likely to have comorbidities and multivessel disease, and more often treated within 12 hours of symptom onset than those without PPAC. After IPTW adjustment for baseline differences, PPAC was associated with significantly reduced risk of in-hospital mortality (0.9% vs. 1.8%; hazard ratio (HR): 0.62 [95% confidence interval 0.43, 0.89]; p&lt;0.001) and a nonsignificant difference in risk of in-hospital major bleeding (2.5% vs. 2.2%; HR: 1.05 [0.83, 1.32]; p=0.14).

Conclusions

PPAC in STEMI patients after pPCI was associated with reduced mortality without increasing major bleeding complications. Dedicated randomized trials with contemporary STEMI management are needed to confirm these findings.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): The Improving Care for Cardiovascular Disease in China – Acute Coronary Syndrome (CCC-ACS) project is a collaborative study of the American Heart Association (AHA) and the Chinese Society of Cardiology (CSC). The AHA has been funded by Pfizer and AstraZeneca for quality improvement initiatives through an independent grant. In-hospital clinical outcomes

Efflux transporters in rat placenta and developing brain: transcriptomic and functional response to paracetamol

Adenosine triphosphate binding cassette (ABC) transporters transfer lipid-soluble molecules across cellular interfaces either directly or after enzymatic metabolism. RNAseq analysis identified transcripts for ABC transporters and enzymes in rat E19, P5 and adult brain and choroid plexus and E19 placenta. Their functional capacity to efflux small molecules was studied by quantitative analysis of paracetamol (acetaminophen) and its metabolites using liquid scintillation counting, autoradiography and ultra-performance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS). Animals were treated acutely (30 min) and chronically (5 days, twice daily) with paracetamol (15 mg/kg) to investigate ability of brain and placenta barriers to regulate ABC transport functionality during extended treatment. Results indicated that transcripts of many efflux-associated ABC transporters were higher in adult brain and choroid plexus than at earlier ages. Chronic treatment upregulated certain transcripts only in adult brain and altered concentrations of paracetamol metabolites in circulation of pregnant dams. Combination of changes to metabolites and transport system transcripts may explain observed changes in paracetamol entry into adult and fetal brains. Analysis of lower paracetamol dosing (3.75 mg/kg) indicated dose-dependent changes in paracetamol metabolism. Transcripts of ABC transporters and enzymes at key barriers responsible for molecular transport into the developing brain showed alterations in paracetamol pharmacokinetics in pregnancy following different treatment regimens.

LncRNA CASC2 inhibits cell proliferation, metastasis and EMT through miR-18a/SOCS5 axis in cholangiocarcinoma

OBJECTIVE

Cholangiocarcinoma (CCA) is one of the tumors with high malignancy of the liver and bile system, whose development and prognosis mechanisms are still not clear. Here, a preliminary illustration was made on the expression and function of long non-coding RNA (lncRNA) CASC2 and the relevant mechanism of its function.

PATIENTS AND METHODS

Expression of CASC2 in CCA tissues and cells were examined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Cell proliferation ability was detected using colony formation and Cell Counting Kit-8 (CCK-8) assays while cell invasion and migration abilities were measured using transwell and Matrigel assays. Using bioinformatic analysis, underlying downstream molecules of CASC2 were predicted and by Dual-Luciferase assay and Western blot.

RESULTS

It was found that CASC2 was expressed at a significantly lower level in CCA tissues and cell lines. The overexpression of CASC2 inhibited QBC939 cell proliferation, invasion and migration when the knockdown of CASC2 accelerated HUCCT1 cell growth and metastasis. Besides, miR-18a was identified as a direct target for CASC2, and SOCS5 as target for miR-18a. Moreover, CASC2 functioned as a sponge of miR-18a to promote the SOCS5 expression, then, slowed down the epithelial-to-mesenchymal transition (EMT) progression.

CONCLUSIONS

CASC2 was downregulated in CCA tissues and cells. It could inhibit cell proliferation, invasion, migration and EMT via sponging miR-18a/SOCS5 axis. This might provide a novel target for CCA diagnosis and treatment.

Association of C1q/TNF-related protein-9 (CTRP9) level with obstructive sleep apnea in patients with coronary artery disease

Background

Obstructive sleep apnea (OSA) is closely related to the incidence and progression of coronary artery disease (CAD), but the mechanisms linking OSA and CAD are unclear. C1q/TNF-related protein-9 (CTRP9) is a novel adipokine that protects the heart against ischemic injury and ameliorates cardiac remodeling.

Purpose

We aimed to ascertain the clinical relevance of CTRP9 with OSA prevalence in patients with CAD.

Methods

From August 2016 to March 2019, consecutive eligible patients with CAD (n=154; angina pectoris, n=88; acute myocardial infarction [AMI], n=66) underwent cardiorespiratory polygraphy during hospitalization. OSA was defined as an apnea-hypopnea index (AHI) ≥15 events h–1. Plasma CTRP9 concentrations were measured by ELISA method.

Results

OSA was present in 89 patients (57.8%). CTRP9 levels were significantly decreased in the OSA group than in the non-OSA group (4.7 [4.1–5.2] ng/mL vs. 4.9 [4.4–6.0] ng/mL, P=0.003). The difference between groups was only observed in patients with AMI (3.0 [2.3–4.9] vs. 4.5 [3.2–7.9], P=0.009), but not in patients with AP (5.0 [4.7–5.3] ng/mL vs. 5.1 [4.7–5.9] ng/mL, P=0.571) (Figure 1). Correlation analysis showed that CTRP9 levels were negatively correlated with AHI (r=−0.238, P=0.003) and oxygen desaturation index (r=−0.234, P=0.004), and positively correlated with left ventricular ejection fraction (r=0.251, P=0.004) in all subjects. Multivariate analysis showed that male gender (OR 3.099, 95% CI 1.029–9.330, P=0.044), body mass index (OR 1.148, 95% CI 1.040–1.268, P=0.006), and CTRP9 levels (OR 0.726, 95% CI 0.592–0.890, P=0.002) were independently associated with the prevalence of OSA.

Conclusions

Plasma CTRP9 levels were independently related to the prevalence of OSA in patients with CAD, suggesting that CTRP9 might play a role in the pathogenesis of CAD exacerbated by OSA.

Figure 1. CTRP9 levels in OSA and non-OAS groups

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Natural Science Foundation of China

Serum Stem Cell Factor Level Predicts Decline in Kidney Function in Healthy Aging Adults

BACKGROUND AND OBJECTIVES

Stem cell factor (SCF), the ligand of the c-kit receptor, actively participates in the organ reconstruction and fibrosis associated with various diseases, including kidney disease. However, it remains unclear whether SCF plays a role in kidney aging.

DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS

In the present study, we measured the serum SCF level, estimated glomerular filtration rate (eGFR), and other biological parameters in a Chinese Han group of 892 subjects, and explored the relationship between SCF level and renal function during aging; we sought to define novel biomarkers of kidney aging.

RESULTS

Multiple linear regression was used to select potential indicators of decline in renal function. Only age, SCF level, and 25% maximum expiratory flow (25% MEF) were significant predictors after redundancy analysis (|r| > 0.70 and P < 0.05). Multiple linear regression showed that the relationship among eGFR, SCF level, and age could be described as follows: eGFR = 154.486 - (0.846 × age) - (0.011 × SCF level).

CONCLUSIONS

We found no between-gender difference in the effect of SCF on kidney aging. In conclusion, the SCF level is an ideal biomarker of renal aging and may help to predict changes in eGFR during aging.

Measurement of circulating tumor cells in squamous cell carcinoma of the head and neck and patient outcomes

OBJECTIVES

We report the outcomes of patients with squamous cell carcinoma of the head and neck (HNSCC) whose circulating tumor cells (CTCs) were quantified using surface-enhanced Raman scattering (SERS) nanotechnology.

METHODS

SERS tagged with EGF was used to directly measure targeted CTCs. Patient charts were retrospectively reviewed. An optimal cut point for CTCs in 7.5 ml of peripheral blood predictive of for distant metastasis-free survival (DMFS) was identified by maximizing the log-rank statistic. An ROC analysis was also performed.

RESULTS

Of 82 patients, 13 experienced metastatic progression. The optimal cut point for DMFS was 675 CTCs (p = 0.047). For those with distant recurrence (n = 13) versus those without distant recurrence (n = 69), the CTC cut point which results in the largest combined sensitivity and specificity values is also 675 (sensitivity = 69%, specificity = 68%).

CONCLUSION

Liquid biopsy techniques in HNSCC show promise as a means of identifying patients at greater risk of disease progression.

An integrated bi-level optimization model for air quality management of Beijing's energy system under uncertainty

In this study, an interval chance-constrained bi-level programming (ICBP) method is developed for air quality management of municipal energy system under uncertainty. ICBP can deal with uncertainties presented as interval values and probability distributions as well as examine the risk of violating constraints. Besides, a leader-follower decision strategy is incorporated into the optimization process where two decision makers with different goals and preferences are involved. To solve the proposed model, a bi-level interactive algorithm based on satisfactory degree is introduced into the decision-making processes. Then, an ICBP based energy and environmental systems (ICBP-EES) model is formulated for Beijing, in which air quality index (AQI) is used for evaluating the integrated air quality of multiple pollutants. Result analysis can help different stakeholders adjust their tolerances to achieve the overall satisfaction of EES planning for the study city. Results reveal that natural gas is the main source for electricity-generation and heating that could lead to a potentially increment of imported energy for Beijing in future. Results also disclose that PM₁₀ is the major contributor to AQI. These findings can help decision makers to identify desired alternatives for EES planning and provide useful information for regional air quality management under uncertainty.

Chronic perfluorooctanesulfonic acid exposure disrupts lipid metabolism in zebrafish

Perfluorooctanesulfonic acid (PFOS), a ubiquitous contaminant, has been used in various industrial applications. Currently few studies have documented the effects of chronic PFOS exposure on lipid metabolism, especially in aquatic organisms. The present study defined the effects of chronic exposure to low level of PFOS on lipid metabolism in F0 adult zebrafish and F1 offspring. Our findings revealed a severe fatty degeneration in the liver of F0 males treated with 0.5 μM PFOS and significant ultrastructure changes associated with substance transport or metabolism in liver and intestines (abnormal mitochondria and endoplasmic reticulum, disordered arrangement of inner microvilli within intracellular canaliculus). To address the potential trans-generational effects of PFOS exposure, the early gene expression related to lipid metabolism was measured by real-time quantitative polymerase chain reaction in F1 derived from chronically exposed parental fish. The results indicated that lepa (leptin α), kiss1 (kisspeptins), xdh (xanthine dehydrogenases), and insr (insulin receptor) were significantly upregulated in F1 while dgat1b (diacylglycerol O-acyltransferase), hb9 (motor neuron/pancreas homeobox), and Apoa1 (apolipoprotein A-I) were downregulated. These findings provided evidence that PFOS chronic exposure adversely impacts lipid metabolism in both F0 and F1 and demonstrated the validity of using zebrafish as an alternative model for PFOS chronic toxicity screening.

An integrated optimization method for river water quality management and risk analysis in a rural system

In this study, an interval-stochastic-based risk analysis (RSRA) method is developed for supporting river water quality management in a rural system under uncertainty (i.e., uncertainties exist in a number of system components as well as their interrelationships). The RSRA method is effective in risk management and policy analysis, particularly when the inputs (such as allowable pollutant discharge and pollutant discharge rate) are expressed as probability distributions and interval values. Moreover, decision-makers' attitudes towards system risk can be reflected using a restricted resource measure by controlling the variability of the recourse cost. The RSRA method is then applied to a real case of water quality management in the Heshui River Basin (a rural area of China), where chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP), and soil loss are selected as major indicators to identify the water pollution control strategies. Results reveal that uncertainties and risk attitudes have significant effects on both pollutant discharge and system benefit. A high risk measure level can lead to a reduced system benefit; however, this reduction also corresponds to raised system reliability. Results also disclose that (a) agriculture is the dominant contributor to soil loss, TN, and TP loads, and abatement actions should be mainly carried out for paddy and dry farms; (b) livestock husbandry is the main COD discharger, and abatement measures should be mainly conducted for poultry farm; (c) fishery accounts for a high percentage of TN, TP, and COD discharges but a has low percentage of overall net benefit, and it may be beneficial to cease fishery activities in the basin. The findings can facilitate the local authority in identifying desired pollution control strategies with the tradeoff between socioeconomic development and environmental sustainability.

AMP-activated protein kinase regulates autophagic protection against cisplatin-induced tissue injury in the kidney

Although the nephrotoxicity of cisplatin has been well documented as a major side effect of chemotherapy, the exact mechanism by which prosurvival and apoptotic pathways interplay to determine renal pathology remains elusive. Recent studies suggested that autophagy might serve as an adaptive mechanism to promote cell survival during acute kidney injury (AKI). We have used AKI as a disease model to investigate the mechanism regulating the cytoprotective role of autophagy in cisplatin-induced tissue damage. Pharmacological inhibitors such as chloroquine were used to manipulate autophagy during AKI, and DNA damage was evaluated by using the cellular marker γH2AX. Cisplatin induced extensive DNA damage during AKI. Autophagy activation served as a survival strategy to suppress cisplatin-induced DNA damage in the pathology of AKI both in vitro and in vivo. Interestingly, in the kidney, cisplatin treatment can activate AMP-activated protein kinase (AMPK), a signaling molecule that is also critical for p53-mediated inactivation of mammalian target of rapamycin (mTOR) pathways. As a result, inhibition or knockdown of AMPK can lead to repressed autophagy in cisplatin-induced AKI, resulting in more DNA damage. Activation of AMPK regulates autophagy during cisplatin-induced AKI. Given the fact that p53 can regulate autophagy by inactivating mTOR via AMPK, our results suggest that the p53 pathway may also play a critical role in the pathogenesis of cisplatin-induced renal damage. This study may further our understanding of the physiological roles of autophagy in the pathogenesis of renal injuries, and thus may have pathological implications in the clinical setting.

Prevalence and influencing factors of depressive symptoms among women of reproductive age in the rural areas of Hubei, China

OBJECTIVES

Depression is one of the most common mental disorders and a major public health problem in the Chinese population, especially among women. The current study aims to understand prevalence of depression symptoms and provide detailed epidemiological factors associated with depression among reproductive women in rural areas which was paid less attention in previous surveys.

STUDY DESIGN

Cross-sectional study.

METHODS

Face-to-face household interviews were conducted on 1058 women (age: 15-49 years) in rural areas from July 2012 to August 2012. Questionnaires were used to investigate the influencing factors of depression among women. Pearson's χ(2), logistic regression analysis and structural equation modelling (SEM) were applied to analyze the related factors.

RESULTS

The prevalence of depression among women was 30.7% [95% confidence interval (CI): 27.9%-33.5%]. Compared with non-depressed individuals, those with depression were more likely to be short of social support [odd ratio (OR): 0.940, P < 0.001) and have no one to talk with (OR: 0.366, P < 0.001), to be dissatisfied with the house (OR: 2.673, P < 0.001) and economy (OR: 2.268, P < 0.01) of their family, and to have great pressure (OR: 2.099, P < 0.01), negative life events (OR: 1.485, P < 0.05) and physical diseases (OR: 1.364, P < 0.05). Pressure status, social support assessment, and socio-economic status were negatively related to depression (correlation coefficient: -0.57, -0.27 and 0.17).

CONCLUSIONS

The high prevalence of depression among reproductive women in rural areas is of particular concern. Factors associated with depression may assist health care administrations to identify and assess high-risk women and target strategies accordingly.

Orientation-dependent growth mechanisms of graphene islands on Ir(111)

Using low-energy electron microscopy, we find that the mechanisms of graphene growth on Ir(111) depend sensitively on island orientation with respect to Ir. In the temperature range of 750-900 °C, we observe that growing rotated islands are more faceted than islands aligned with the substrate. Further, the growth velocity of rotated islands depends not only on the C adatom supersaturation but also on the geometry of the island edge. We deduce that the growth of rotated islands is kink-nucleation-limited, whereas aligned islands are kink-advancement-limited. These different growth mechanisms are attributed to differences in the graphene edge binding strength to the substrate.

Association between IRF5 polymorphisms and autoimmune diseases: a meta-analysis

In this study, we investigated the association between 5 interferon regulatory factor-5 (IRF5) single nucleotide polymorphisms (SNPs) and autoimmune diseases using the Medline citation index. Twenty-eight studies with 74 comparisons, including 16 rheumatoid arthritis (RA), 43 systemic lupus erythematous (SLE), 2 juvenile idiopathic arthritis (JIA), 6 multiple sclerosis (MS), and 5 systemic sclerosis (SSc) studies, were examined in the meta-analysis. The SNP rs2004640 was significantly associated with SLE, MS, and SSc, but not with JIA [odds ratio (OR)=1.06, 95% confidence interval (CI)=0.90-1.24, P=0.48] or RA (OR=1.03, 95%CI=0.95-1.11, P=0.44). A significant association was observed between rs2280714 and SLE, MS, and SSc, but not RA (OR=1.01, 95%CI=0.94-1.09, P=0.80). Rs10954213 was associated with the pathogenesis of SLE, RA, MS, and SSc. rs2070197 and the exon 6 insertion were significantly associated with SLE. Haplotypes containing rs2004640T and rs2280714T were significantly associated with an increased risk of SLE, but not with RA. This meta-analysis certified that IRF5 polymorphisms confer susceptibility to SLE, MS, and SSc. To further confirm the correlations between polymorphisms of IRF5 and autoimmune disease susceptibility, studies involving a larger number of patients worldwide are necessary.

Association of Helicobacter pylori infection with esophageal adenocarcinoma and squamous cell carcinoma: a meta-analysis

To evaluate the relationship of Helicobacter pylori and cytotoxin-associated gene A (CagA) positive strains with esophageal neoplasm, including esophageal adenocarcinoma (EAC) and esophageal squamous cell carcinoma (ESCC), the authors conducted a meta-analysis using a predefined protocol. PubMed, Web of Science, China biology medical literature database, Wanfang, and China National Knowledge Infrastructure were searched for relevant articles from the first available year to April 8, 2013. The fixed or random effect pooled measure was selected based on heterogeneity among studies, which was evaluated using Q test and the I(2) of Higgins and Thompson. Metaregression was used to explore the sources of between-study heterogeneity. Publication bias was analyzed by Begg's funnel plot and Egger's regression test. The association was assessed by odds ratio (OR) with 95% confidence interval (CI). A total of 28 eligible studies were included in the meta-analysis. There was a significant inverse association between H. pylori infection (pooled OR, 0.57; 95% CI, 0.44-0.73) and EAC; CagA-positive H. pylori strains were less likely to be associated with EAC compared with CagA-negative strains (pooled OR, 0.64; 95% CI, 0.52-0.79). However, there was no statistically significant association between H. pylori/CagA-positive H. pylori strains infection and ESCC, and the pooled ORs were 1.16 (95% CI, 0.83-1.60) and 0.97 (95% CI, 0.79-1.19). But significant associations between CagA-positive H. pylori strains infection and ESCC risk were found in the stratified analysis of the study location (Asian and non-Asian), and the summary ORs were 0.74 (95% CI, 0.57-0.97) and 1.41 (95% CI, 1.02-1.94). H. pylori infection and CagA-positive strains are associated with decreased risk of EAC in the overall population. No significant association was found between H. pylori infection/CagA-positive strains and ESCC. But CagA-positive strains might have a positive association with ESCC in non-Asian population and an inverse association in Asian population.

Chinese urban-rural disparity in pandemic (H1N1) 2009 vaccination coverage rate and associated determinants: a cross-sectional telephone survey

OBJECTIVES

The present study aimed to examine the differences in pandemic (H1N1) 2009 vaccination coverage rate between urban and rural areas in China, and to explore factors associated with any urban-rural differences.

STUDY DESIGN

Cross-sectional study.

METHODS

Data were derived from a cross-sectional telephone survey performed in seven urban and two rural areas soon after the pandemic peak in China, concerning pandemic (H1N1) 2009 vaccination and associated knowledge, attitudes and practices among the general population in China. A total of 10 669 participants aged 18 years and above participated in the study.

RESULTS

Vaccination amongst rural residents was less than urban residents (8.9% vs 11.2%, P = 0.002). Among those who have not been immunized, 82.2% of rural respondents showed a willingness to get vaccinated against A/H1N1, significantly higher than that of urban respondents (55.3%). The major barrier to vaccination was reported as 'not being informed to get vaccination', of which there was a greater proportion in rural than urban population (71.9% vs 68.8%, P = 0.009). The analysis revealed a number of factors which contribute to this disparity: previous experience of vaccination against flu, degree of awareness of the free vaccination policy, and sociodemographic differences between urban and rural areas.

CONCLUSIONS

Significant discrepancies existed in the pandemic (H1N1) 2009 vaccination coverage rate and associated determinants, as well as the intention to get vaccinated between urban and rural residents. To improve the effectiveness of similar vaccination programmes in the future, campaigns for rural people need to be specifically tailored to address disparities in uptake.

Gonococcal endocarditis: a case report and literature review

Gonococcal endocarditis is rarely encountered in the post-antibiotic era. This case report describes a case of a previously healthy male who presented with double quotidian fever, chills, cough, and urethral symptoms. The presence of a cardiac mitral valvular vegetation along with positive blood cultures for Neisseria gonorrhoeae were diagnostic for gonococcal endocarditis. This case was, to our knowledge, the first reported gonococcal endocarditis case in China.

Sex differences in stroke case fatality: a meta-analysis

BACKGROUND

In recent years, there were great controversies about gender disparities in stroke outcome. The study was aimed to investigate sex differences in stroke case fatality on all published studies based in a comprehensive meta-analysis.

METHODS

A systematic search of Pubmed, EMBASE, SCOPUS, ISI Web of Science, and Cochrane Library was conducted for the included papers between 1992 and 2009. For the pooled group and subgroup analysis, fixed effects or random effects model were used to find sex differences in case fatality of stroke with a Mantel-Haenszel method. Meta-regression analysis was performed to study methodological heterogeneity.

RESULTS

Thirty-six population-based studies, together with three randomized clinical trials (RCTs), were included in the present study. For the pooled group, there was an overall hazard risk of 1.13 for women compared with men. A hazard risk of 1.27 was observed for women in RCTs subgroup and 1.12 for women in population-based subgroup. The regression analysis found no significant correlation between methodological variables and heterogeneity.

CONCLUSIONS

Due to the limited data about sex differences in stroke case fatality, the findings should be treated cautiously as preliminary. More large multicenter clinical trials should be performed to verify the reliability of the results.

Neural crest specification: tissues, signals, and transcription factors

The neural crest is a transient population of multipotent and migratory cells unique to vertebrate embryos. Initially derived from the borders of the neural plate, these cells undergo an epithelial to mesenchymal transition to leave the central nervous system, migrate extensively in the periphery, and differentiate into numerous diverse derivatives. These include but are not limited to craniofacial cartilage, pigment cells, and peripheral neurons and glia. Attractive for their similarities to stem cells and metastatic cancer cells, neural crest cells are a popular model system for studying cell/tissue interactions and signaling factors that influence cell fate decisions and lineage transitions. In this review, we discuss the mechanisms required for neural crest formation in various vertebrate species, focusing on the importance of signaling factors from adjacent tissues and conserved gene regulatory interactions, which are required for induction and specification of the ectodermal tissue that will become neural crest.

Using neural network as a screening and educational tool for abnormal glucose tolerance in the community

Background

Accurate, simple and non-invasive tools are needed for efficient screening of abnormal glu-cose tolerance (AGT) and educating the general public.

Aim

To develop a neural network-based initial screening and educational model for AGT.

Data and methods

230 subjects with AGT and 3,243 subjects with normal glucose tolerance (NGT) were allocated into training, validation and test sets using stratified randomization. The ratios of AGT versus NGT in three groups were 150:50, 30:570 and 50:950, respectively. A feed-forward neural network (FFNN) was trained to predict 2-hour plasma glucose of 75 g Oral Glucose Tolerance Test (OGTT) using age, family history of diabetes, weight, height, waist and hip circumference. The screening performance was evaluated by the area under the receiver operating characteristic (ROC) curve (AUC) and the partial AUC (in the range of false positive rates between 35 and 65%) and compared to those from logistic regression, linear regression and ADA Risk Test.

Results

Sensitivity, specificity, accuracy and percentage that needed further testing at 7.2 mmol/L in test group were 90.0%(95%CI: 78.6 to 95.7%), 47.7% (95%CI: 44.5 to 50.9%), 49.8% (95%CI: 46.7 to 52.9%) and 54.2% (95%CI: 51.1 to 57.3%) respectively. The entire and partial AUCs were 0.70 (95%CI: 0.62 to 0.78) and 0.26 (95%CI: 0.22 to 0.30). The partial AUC of the NN was higher than those of logistic regression (p = 0.06), linear regression (p = 0.06) and ADA Risk Test (P = 0.006).

Conclusion

NN can be used as a high-sensitive and non-invasive initial screening and educational tool for AGT.

Pentagons and heptagons in the first water layer on Pt(111)

Scanning tunneling topography of long-unexplained "square root of 37" and "square root of 39" periodic wetting arrangements of water molecules on Pt(111) reveals triangular depressions embedded in a hexagonal H2O-molecule lattice. Remarkably, the hexagons are rotated 30° relative to the "classic bilayer" model of water-metal adsorption. With support from density functional theory energetics and image simulation, we assign the depressions to clusters of flat-lying water molecules. 5- and 7-member rings of H2O molecules separate these clusters from surrounding "H-down" molecules.

Improving emergency preparedness capability of rural public health personnel in China

OBJECTIVES

Since the outbreaks of severe acute respiratory syndrome and avian influenza, improving the emergency preparedness capability of rural public health personnel has become a new priority in building the infrastructure needed to address public health emergencies. The Chinese Government has carried out a series of emergency preparedness education and training programmes to improve the emergency preparedness capability of rural public health personnel nationwide. The purpose of this study was to evaluate and develop a participatory emergency preparedness training programme for rural public health personnel.

STUDY DESIGN

The research emphasizes the major components of instructional design, including assessing, designing, delivering and evaluating training. The approach is an integrated system with results from one phase influencing the next, so that a series of steps are followed when developing, implementing and evaluating emergency preparedness training.

METHODS

The 226 participants were rural public health personnel from 84 different rural centres for disease control and prevention in China. The programme was evaluated by anonymous questionnaires and semi-structured interviews held prior to training, immediately post-training and 12-months after training (follow-up).

RESULTS

The emergency preparedness training resulted in positive shifts in knowledge and skills for rural public health personnel. At follow-up, the knowledge and skill scores of participants declined slightly compared with the post-test levels (P>0.05). However, there was a significant increase compared with the pre-test levels (P<0.01). Moreover, more than 90% of participants reported that this training provided a valuable learning experience and reinforced the importance of emergency preparedness.

CONCLUSIONS

The emergency preparedness training programme was effective and feasible in improving the performance of rural public health personnel on emergency response. Further studies are needed to test the efficacy of the training approach for competency improvement.

Observation of surface self-diffusion on ice

To determine the role of surface diffusion on the morphology of ice surfaces we track the evolution with STM of 2D ice-island arrays on the basal surface of ice films on Pt(111) between 115 and 135 K. In contrast with previous measurements at higher temperatures, we find that the evolution is dominated by surface diffusion. The extracted surface self-diffusion coefficient has an activation energy of 0.4+/-0.1 eV, much less than the value previously measured for bulk diffusion.

Multifunctional and multiplexed nanoparticles for molecular imaging and treatment of breast cancer

Abstract #6003

Multifunctional nanoparticles with the ability to target tumors, provide molecular imaging and to deliver therapeutic agents hold great promise for improving the survival of cancer patients. We have developed multifunctional nanoparticles targeted to cellular receptors that are highly expressed in breast cancer and tumor stromal cells. Fluorescent quantum dot (QD) or magnetic iron oxide (IO) nanoparticles are conjugated to either the amino-terminal fragment (ATF) of urokinase plasminogen activator (uPA) or to a single chain antibody against the epidermal growth factor receptor (ScFvEGFR), resulting in uPAR or EGFR targeted nanoparticles. Since the binding of ATF peptides or ScFvEGFR to their receptors results in blocking receptor function and internalization of the receptor-ligand complex, these targeted imaging probes can also inhibit tumor growth and deliver drugs. Using near infrared fluorescence (NIR) dye-labeled targeting peptides, we demonstrate specificity of these targeting ligands in an orthotopic human breast cancer model in nude mice. We found that tail vein injection of a mixture of Cy5.5 dye-ATF and IRDye 800-ScFvEGFR peptides leads to the selective accumulation of both probes in human breast cancer xenografts and NIR optical imaging of the tumors in the mammary fat pad of nude mice (Fig. A).&#x2028; &#x2028; We show that uPAR- and EGFR-targeted nanoprobes display different patterns of intratumoral distribution with EGFR probes in the central area and uPAR probes in the peripheral and central regions of the tumor, which may be the results of expressing uPAR in the invasive edge of tumor cells and tumor stromal cells and EGFR only in tumor cells. In vivo optical imaging using ATF-nanoparticles is also demonstrated in human breast cancer xenograft (Fig. B) and in mouse mammary tumor lung metastatic models. Furthermore, magnetic Cy5.5-ATF IO nanoparticles are multimodality imaging probes for both optical and MR tumor imaging. Since magnetic IO nanoparticles are biodegradable and relatively safe for human use, we have developed a therapeutic imaging nanoparticle by encapsulating doxorubicin into the polymer coating of the nanoparticles and have shown selective delivery of the drug and cytotoxic effect in breast cancer cells in vitro. Results of our study show that multifunctional and multiplexed nanoparticles have great potential for the development of novel tumor imaging and therapeutic approaches.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6003.

Insulin-like growth factor-1 receptor polymorphism and ischemic stroke: a case-control study in Chinese population

OBJECTIVES

Low levels of insulin-like growth factor 1 (IGF-1) are associated with atherosclerosis, and insulin-like growth factor-1 receptor (IGF-1R) polymorphisms can change plasma levels of IGF-1 and may alter the function of the receptor. Whether there is any association of genetic variation in IGF-1R gene with ischemic stroke (IS) is presently unknown.

MATERIALS AND METHOD

A 1:1 case-control study was conducted. The G --> A polymorphism of IGF-1R gene (rs2229765) were analyzed by TaqMan SNP genotyping technique in Chinese patients with IS (n = 309) and old subjects without IS (n = 309).

RESULTS

The frequency of A allele in the patients and controls was 45.79% and 39.64%, respectively. The AA genotype distribution of IGF-1R gene was significantly higher in the patients (27.51%) than controls (18.23%; P = 0.022). Conditional logistic regression revealed that the AA genotype of IGF-1R was associated with IS (OR = 1.641, P = 0.022). After adjustment for smoking, alcohol drinking, history of hypertension, and body mass index, IGF-1R AA genotype was still significantly associated with an increased risk of IS (OR = 1.787, P = 0.029), compared with IGF-1R GG.

CONCLUSIONS

The G --> A polymorphism in IGF-1R gene may affect the susceptibility to IS in Chinese population.

Optical control of coherent lattice motions probed by femtosecond electron diffraction

We report the study of laser-induced coherent lattice motions using femtosecond electron diffraction. The oscillations of Bragg peak positions associated with a damped lattice vibration along the surface normal were directly observed in real time and with sub-milli-angstrom spatial resolution. In addition, by using a pair of optical excitation pulses and varying their time delay and relative pulse intensities, we demonstrated the successful control of coherent lattice motions.

Difference of NPY and its receptor gene expressions between obesity and obesity-resistant rats in response to high-fat diet

AIM

To investigate the effect of high-fat diet on expressions of hypothalamic neuropeptide Y (NPY) and Y1, Y2, Y5 receptors and the mechanism relative to the susceptibility of obesity.

METHODS

Thirty-six female SD rats were randomly divided into high-fat diet group (HF, n=27) and chow food group (CF, n=9), and given either HF or CF diet for 13 weeks. Then the HF diet group was subdivided into dietary induced obesi-ty (DIO) and dietary induced obesity resistant (DIO-R) rat according to the final body weight. Body weight, caloric intake, energy efficiency, visceral fat pads were measured and compared. The levels of plasma and hypothalamic NPY were determined by Radioimmunoassay. Real-time Polymerase Chain Reaction (PCR) was used to measure the gene expression of NPY and its receptors in hypothalamus.

RESULTS

Body weight, caloric intake, energy efficiency and visceral fat pads in DIO rats were higher significantly than those in CF or DIO-R rats (p<0.01). No difference in plasma NPY level was detected among the three groups (p>0.05); the hypothalamic NPY level was significantly higher in DIO group than in CF or DIO-R group (p<0.01). Gene expression levels of NPY and Y1, Y2, Y5 receptors were higher significantly in DIO group than in CF or DIO-R group (p<0.01), while no significant difference was found between DIO-R and CF rats (p>0.05), except that Y2 receptor was lower in DIO-R rats (p<0.01).

CONCLUSIONS

SD rat fed with a HF diet showed different susceptibility to obesity, and up-regulated hypothalamic NPY and Y1, Y2, Y5 receptor gene expressions were closely associated with being predisposed to obesity and overeating of DIO rats.