Recent progress on topological semimetal IrO2: electronic structures, synthesis, and transport properties

5dtransition metal oxides, such as iridates, have attracted significant interest in condensed matter physics throughout the past decade owing to their fascinating physical properties that arise from intrinsically strong spin-orbit coupling (SOC) and its interplay with other interactions of comparable energy scales. Among the rich family of iridates, iridium dioxide (IrO2), a simple binary compound long known as a promising catalyst for water splitting, has recently been demonstrated to possess novel topological states and exotic transport properties. The strong SOC and the nonsymmorphic symmetry that IrO2possesses introduce symmetry-protected Dirac nodal lines (DNLs) within its band structure as well as a large spin Hall effect in the transport. Here, we review recent advances pertaining to the study of this unique SOC oxide, with an emphasis on the understanding of the topological electronic structures, syntheses of high crystalline quality nanostructures, and experimental measurements of its fundamental transport properties. In particular, the theoretical origin of the presence of the fourfold degenerate DNLs in band structure and its implications in the angle-resolved photoemission spectroscopy measurement and in the spin Hall effect are discussed. We further introduce a variety of synthesis techniques to achieve IrO2nanostructures, such as epitaxial thin films and single crystalline nanowires, with the goal of understanding the roles that each key parameter plays in the growth process. Finally, we review the electrical, spin, and thermal transport studies. The transport properties under variable temperatures and magnetic fields reveal themselves to be uniquely sensitive and modifiable by strain, dimensionality (bulk, thin film, nanowire), quantum confinement, film texture, and disorder. The sensitivity, stemming from the competing energy scales of SOC, disorder, and other interactions, enables the creation of a variety of intriguing quantum states of matter.

[Cost-effectiveness of anti-tumor associated antigen autoantibody screening for hepatocellular carcinoma in the population with chronic hepatitis B-related cirrhosis]

Objective: To evaluate the cost-effectiveness of anti-tumor associated antigen autoantibody (TAAb) for hepatocellular carcinoma (HCC) screening in cirrhosis population with chronic hepatitis B (CHB). Methods: A simulated cohort of 40-year-old patients with CHB cirrhosis was established with a sample size of 10 000. Using TAAb screening alone or TAAb and AFP screening in parallel (TAAb + AFP) as the research strategy, and liver ultrasound and AFP screening in parallel (liver ultrasound + AFP) as the control strategy, the decision analysis Markov model was constructed and the model validity was evaluated. The 6-month cycle was simulated using TreeAge Pro 2020 software. Cost and quality-adjusted life years (QALY) were calculated. Incremental cost-effectiveness ratio (ICER) was used to compare the two strategies, and sensitivity analysis was used to evaluate the uncertainty of results. Results: The Markov model had a total of 11 outcomes, of which 7 were natural outcomes and 4 wereclinical intervention outcomes, and the goodness of fit was 0.969. The lifetime screening cost of TAAb+AFP strategy for HCC screening was 249 612 yuan/case, and the QALY per capita was 7.704 years. Compared with liver ultrasound +AFP strategy (247 805 yuan/case), the total health cost increased by 1 807 yuan/case, and the QALY obtained was 0.014. The ICER was 127 635 yuan /QALY. When the TAAb screening fee was higher than 889.552 yuan, or the discount rate was higher than 0.068, or the antiviral treatment compliance was lower than 45.1%, ICER > 212 676 yuan /QALY. When the single TAAb screening fee was 400-600 yuan, the TAAB+AFP strategy had cost effective value. When the willingness to pay was 70 892, 141 784 and 212 676 yuan /QALY, the probability of cost-effectiveness of TAAb+AFP strategy was 70.6%, 75.3% and 77.8%, respectively. Conclusion: It is cost-effective to use TAAb+AFP for early screening of liver cancer in Chinese population with CHB cirrhosis.

Measurement of the Cosmic Ray Helium Energy Spectrum from 70 GeV to 80 TeV with the DAMPE Space Mission

The measurement of the energy spectrum of cosmic ray helium nuclei from 70 GeV to 80 TeV using 4.5 years of data recorded by the Dark Matter Particle Explorer (DAMPE) is reported in this work. A hardening of the spectrum is observed at an energy of about 1.3 TeV, similar to previous observations. In addition, a spectral softening at about 34 TeV is revealed for the first time with large statistics and well controlled systematic uncertainties, with an overall significance of 4.3σ. The DAMPE spectral measurements of both cosmic protons and helium nuclei suggest a particle charge dependent softening energy, although with current uncertainties a dependence on the number of nucleons cannot be ruled out.

[Clinical characteristics of 288 cases of pathologically confirmed benign pulmonary nodules post-surgery]

Objective: To analyze retrospectively the clinical characteristics of pathologically confirmed benign pulmonary nodules post-surgery, and therefore to provide evidence for the diagnosis of benign pulmonary nodules. Methods: 288 cases of pulmonary nodules were selected in the Ruijin Hospital from 1^st January 2017 to 31^st October 2019. All the lesions of these patients were confirmed by surgery and had definite pathological diagnosis. The clinical data were collected, including demography, clinical data, radiological features. Features that indicated benign pulmonary nodules were summarized. Results: The main etiologies of benign pulmonary nodules were granulomas, hamartomas, cryptococcus infection, organizing pneumonia and non-specific inflammation. In our cohort, we found that the radiological characteristics of benign nodules were single, solid, less than 10 mm in average diameter, with well-defined margins, absence of vacuole sign or vascular convergence , and negative functional imaging. Conclusion: The most common etiologies of post-surgical benign nodules were granulomas, hamartomas, and cryptococcus infection, characterized by being single, solid and with well-defined margins. Caution should be taken before considering surgery for such nodules.

[A study of LEF1 protein expression in diagnosis and differential diagnosis of lymphoblastic lymphoma/acute lymphoblastic leukemia]

Objective: To evaluate the expression of LEF1 protein in lymphoblastic lymphoma/acute lymphoblastic leukemia (LBL/ALL) and small B-cell lymphomas, and its value in pathologic diagnosis and differential diagnosis of LBL/ALL. Methods: 53 cases of LBL/ALL were collected at shanghai Tongji Hospital from January 2012 to December 2019. The protein expression of LEF1 and TdT was detected by immunohistochemistry in 53 paraffin-embedded tissue samples of LBL/ALL. The specificity and sensitivity of LEF1 and TdT in the diagnosis of LBL/ALL were compared. The expression of LEF1 protein in 77 cases of small B-cell lymphomas including chronic lymphocytic leukemia/small lymphoid lymphoma (CLL/SLL), follicular lymphoma, mantle cell lymphoma, marginal zone lymphoma and Waldenstrom's macroglobulinemia/lymphoplasmacytic lymphoma was studied. The correlation between LEF1 expression and overall survival (OS) and progression-free survival (PFS) was performed by univariate analysis. Results: The expression of LEF1 in LBL/ALL was 100% (53/53), the median value was 90%; the expression of TdT was 84.9% (T-LBL/ALL 78.1%, B-LBL/ALL 95.2%), the median value was 80%; the expression rate and median value of LEF1 and TdT were significantly different (P=0.008 and 0.001 respectively). The expression of LEF1 in CLL/SLL was 14/18, the median value was 45%; LEF1 was not expressed in follicular lymphoma (0/16), mantle cell lymphoma (0/16), marginal zone lymphoma (0/19), and Waldenstrom's macroglobulinemia/lymphoplasmacytic lymphoma (0/8). LEF1 expression was significantly different between B-LBL/ALL and small B-cell lymphomas. The median follow-up time of LBL/ALL cases in this group was 16 months. There was no statistical difference between LEF1 expression and the OS and PFS in LBL/ALL patients. Conclusions: Immunohistochemical staining of LEF1 has high sensitivity and good specificity in the diagnosis of LBL/ALL, and its combination with TdT can improve the diagnostic rate of LBL/ALL.

[Clinical effect of one-stage total knee arthroplasty for knee osteoarthritis with femoral extra-articular deformity]

Objective: To investigate the application and efficacy of the one-stage total knee arthroplasty (TKA) of intra-articular compensation osteotomy in knee osteoarthritis(KOA) patients with extra-articular deformity (EAD). Methods: A retrospective study of 9 patients with end-stage KOA and EAD undergoing one-stage TKA from January 2014 to December 2017 in the First Affiliated Hospital of Zhejiang Chinese Medical University was performed. There were 3 males and 6 females with an average age of 56 years(range, 19-77 years);5 cases of simple coronal deformity (varus 10°-27°, mean 18.2°), 3 cases of sagittal deformity (recurvatum15°-35°, mean 22.6°), 1 case combined with coronal and sagittal deformity (varus 16°, recurvatum 31°); hemophilia dysplasia in 1 case, fracture malformation in 8 cases. Main outcome measures included the mechanical axis, range of motion (ROM) and Hospital for Special Surgery Knee Score (HSS). Results: The mean follow-up period was 33.2 months (range, 25-47 months). The mechanical axis angle was restored from 12.4°±4.1°to 1.4°±0.9°(t=7.954, P<0.01). The HSS was improved from 28±14 preoperatively to 87±7 postoperatively (t=-11.174, P=0.013). The ROM increased from 56°±22°to 99°±8° (t=-5.480, P=0.010). There was no complications such as joint instability, infection, fracture, common peroneal nerve injury and early prosthesis loosening. Conclusions: For KOA patients with femoral EAD, one-stage TKA with intra-articular compensatory osteotomy can effectively restore the mechanical axis and obtain satisfying joint function. Through a series of measures such as preoperative measurement, soft tissue evaluation and 3D printing, the accuracy of surgery can be improved and the difficulty of surgery can be reduced.

[The analysis of clinical characteristics of 34 novel coronavirus pneumonia cases in Ningxia Hui autonomous region]

Objective: To analyze the clinical characteristics of 34 COVID-19 cases and to provide the basis for the prevention and control of the epidemic disease. Methods: Thirty-four COVID-19 patients diagnosed with RT-PCR in the isolation ward of the Fourth People's Hospital of Ningxia Hui autonomous region (infectious diseases hospital) from the January 22 to February 4, 2020 were selected as the research subjects. The clinical data were collected. Excel was used to describe the relationship between clinical classification and age distribution, contact history and date of onset. SPSS 25.0 statistical software was used for analysis. The general information, clinical symptoms, blood test, virus nucleic acid test results, epidemiology, CT imaging, treatment and prognosis were analyzed. Results: There were 5 mild cases (5/34), 24 ordinary cases (24/34), 5 severe cases (5/34). The elderly was more common in severe patients. The main clinical symptoms were fever (27/34)and dry cough(26/34). The peripheral blood showed normal or decreased leukocyte count (33/34), decreased lymphocyte count (12/34). The increase of C-reactive protein (CRP) and D-dimer was related to the severity of the disease. Some patients had mild liver and kidney damage. Six patients were diagnosed through 3 or more times of nucleic acid tests. Sixteen cases had Wuhan related history,13 cases were close contacts, 5 cases had no confirmed route. The clustered infections were found in 6 families. In typical cases, CT showed single or multiple patchy ground glass shadow with thickening of interlobular septum. In severe cases, diffuse lesions of both lungs were found, with ground glass shadow, consolidation shadow and strip shadow coexisting. Thirty-four patients were treated with interferon-α and Lopinavir/Ritonavir with good prognosis. Conclusions: The clinical characteristics of COVID-19 were similar to that of general viral pneumonia but with strong infectivity. Close contact and family aggregation caused disease outbreaks. COVID-19 could not be excluded if two nucleic acid tests were negative and high-resolution CT was helpful for differential diagnosis. Early detection, early isolation, early diagnosis and early treatment are important for good prognosis. The effectiveness of antiviral drugs needs to be further verified.

Expression and prognostic significance of melatonin receptor MT1 in patients with gastric adenocarcinoma

Melatonin receptor type 1 (MTNR1A or MT1) is known to play an important role in cancer progression; however, its prognostic value for resected gastric adenocarcinoma (RGA) is unknown. In this study, we examined the potential of MT1 as a prognostic biomarker for RGA. The expression of the MT1 was evaluated in 67 patients with RGA by immunohistochemistry, and the relationship between MT1 levels and RGA prognosis was analyzed by Chi-square test, multivariate Cox regression, Kaplan-Meier method, and log-rank test. High MT1 expression was associated with a poor survival rate (29.0%, p=0.002) and the occurrence of metastasis (62.9%, p=0.004). Kaplan-Meier survival analysis and log rank tests revealed that patients with high expression of the MT1 had significantly shorter median overall survival compared to those with low expression (33.0 vs. 65.0 months, respectively; p=0.02). Multivariate Cox analysis indicated that the calculated death risk (hazard ratio [HR]) in patients with high expression levels of the MT1 increased to 2.68 (95% confidence interval [CI] 1.21-5.94, p=0.015), which was higher compared to those with low levels. HR of death was also high in patients with advanced T stage (2.51; 95 % CI 1.00-6.26, p=0.049) and metastasis (5.02; 95% CI 1.94-13.03, p=0.001). Our results showed that high MT1 expression in primary gastric adenocarcinoma tissues was associated with the occurrence of metastasis and poor prognosis. It may have prognostic significance as a potential biomarker in patients with RGA.

[Prevalence and risk factors of Blastocystis hominis infection in inpatients in Jiangjin District, Chongqing City]

OBJECTIVE

To understand the prevalence and risk factors of Blastocystis hominis infection in inpatients in Jiangjin District, Chongqing City.

METHODS

A cross-sectional study was conducted in a community hospital in Jiangjin District, Chongqing City, and the inpatients were surveyed by questionnaires. After obtaining the informed consent from the inpatients or legal guardians, the stool and blood samples were collected and examined by microscopy and PCR from April 17 to May 1, 2018. The univariate analysis and logistic regression analysis were used to analyze the risk factors of the B. hominis infection.

RESULTS

A total of 198 hospitalized patients were investigated, and the infection rate of B. hominis was 10.61% (21/198), and the infection rate of the females (12.10%) was higher than that of the males (8.11%), but the difference was not statistically significant. The highest rate of infection was 19.23% in the age group of 10 to 20 years, followed by 17.74% in the age group of 60 years and above, and the lowest rate was 2.38% in the age group of 20 to 40 years. The difference in infection rates of B. hominis among the different age groups was statistically significant (P < 0.05). The infection rate of B. hominis in the people who used dry pail latrines was 33.30%, which was higher than that of the people who used water flush toilets (9.10%) (P < 0.05). The genotypes of B. hominis were ST1, ST3, ST6 and ST7, and ST6 and ST3 being the most predominant genotypes which accounted for 47.62% (10/21) and 38.10% (8/21) respectively, and among the infected males, the genotypes were only ST3 and ST6. The multiple logistic regression analysis showed that among the factors affecting B. hominis infection, only keeping pets was a risk factor [OR = 3.798, 95% CI (1.245, 11.581), P < 0.05].

CONCLUSIONS

A high prevalence of B. hominis infection is found in the inpatients in Jiangjin District, Chongqing City, the predominant genotypes are ST6 and ST3, and keeping pets may be one of the main risk factors.

[Epidemiological characteristics and risk factors of Blastocystis hominis infection among patients with HIV/AIDS in Fuyang City Anhui Province]

OBJECTIVE

To investigate the prevalence and risk factors of Blastocystis hominis infections among patients with HIV/AIDS in Fuyang City, Anhui Province.

METHODS

A cross-sectional study was conducted in Fuyang City, Anhui Province in 2016. The demographic and socioeconomic status, and the lifestyle and production style were collected using a questionnaire survey. B. hominis DNA was detected in subjects'stool samples using a PCR assay, and the CD4+ T lymphocyte count and HIV viral load were measured in the subjects' blood samples. The risk factors of B. hominis infections among patients with HIV/AIDS were identified using univariate and multivariate logistic regression analyses.

RESULTS

A total of 398 HIV/AIDS patients were enrolled in this study, with a mean age of 49.3 years, a mean body weight of 55.9 kg and a mean height of 164.4 cm. The prevalence of B. hominis infection was 6.78% in the study subjects, and no gender- (χ² = 1.589, P = 0.207), education level- (χ² =0.508, P = 0.776), marital status- (χ² = 0.419, P = 0.811) or occupation-specific prevalence (χ² = 2.744, P = 0.615) was detected. Among the patients with HIV/AIDS, there were no significant differences in the age (t = 0.370, P = 0.712), height (t = 1.587, P =0.113), body weight (t = 0.516, P = 0.606), CD4⁺ T lymphocyte count (t = 1.187, P = 0.230) or HIV viral load (t = 0.193, P =0.496) between B. hominis-infected and uninfected individuals. Dinking non-tap water [OR = 6.554, 95% CI: (1.876 to 22.903)] and keeping dogs [OR = 5.895, 95% CI: (2.017 to 17.225)] were identified as risk factors for B. hominis infection in patients with HIV/AIDS.

CONCLUSIONS

The prevalence of B. hominis infection is high in HIV/AIDS patients, and drinking non-tap water and keeping dogs are risk factors for B. hominis infection among HIV/AIDS patients.

[Development of Markov models for economics evaluation of strategies on hepatitis B vaccination and population-based antiviral treatment in China]

Objective: To construct the Markov models to reflect the reality of prevention and treatment interventions against hepatitis B virus (HBV) infection, simulate the natural history of HBV infection in different age groups and provide evidence for the economics evaluations of hepatitis B vaccination and population-based antiviral treatment in China. Methods: According to the theory and techniques of Markov chain, the Markov models of Chinese HBV epidemic were developed based on the national data and related literature both at home and abroad, including the settings of Markov model states, allowable transitions and initial and transition probabilities. The model construction, operation and verification were conducted by using software TreeAge Pro 2015. Results: Several types of Markov models were constructed to describe the disease progression of HBV infection in neonatal period, perinatal period or adulthood, the progression of chronic hepatitis B after antiviral therapy, hepatitis B prevention and control in adults, chronic hepatitis B antiviral treatment and the natural progression of chronic hepatitis B in general population. The model for the newborn was fundamental which included ten states, i.e. susceptiblity to HBV, HBsAg clearance, immune tolerance, immune clearance, low replication, HBeAg negative CHB, compensated cirrhosis, decompensated cirrhosis, hepatocellular carcinoma (HCC) and death. The susceptible state to HBV was excluded in the perinatal period model, and the immune tolerance state was excluded in the adulthood model. The model for general population only included two states, survive and death. Among the 5 types of models, there were 9 initial states assigned with initial probabilities, and 27 states for transition probabilities. The results of model verifications showed that the probability curves were basically consistent with the situation of HBV epidemic in China. Conclusion: The Markov models developed can be used in economics evaluation of hepatitis B vaccination and treatment for the elimination of HBV infection in China though the structures and parameters in the model have uncertainty with dynamic natures.

[Cost-effectiveness of community-based treatment of chronic hepatitis B in China]

Objective: Since eliminating hepatitis B in China would need considerable public health resources, the economics problem of the strategy of community-based antiviral treatment for chronic hepatitis B (CHB) has become an important issue. The cost-effectiveness and affordability of the strategy were evaluated in this study. Methods: According to the advocacy on eliminating hepatitis B by WHO and the comprehensive protocol of community based prevention of major infectious diseases and the guideline for CHB prevention and treatment in China, the decision analytic Markov model was constructed with the parameters from national surveys or Meta-analysis. A cohort population aged 20-59 years was used as study subjects. The strategy of CHB antiviral treatment was compared with the strategies of hepatitis B vaccination and non-intervention, respectively. The costs and disability-adjusted life years (QALYs) of the strategies were calculated from the societal and payer perspectives. The incremental cost-effectiveness ratio (ICER) and the cost-effectiveness ratio (CER) were calculated for the comparison of the strategies. One-way and probability sensitivity analysis were performed for uncertainty of the results. And the cost-effectiveness and affordability curves were introduced to estimate the budget impact on the strategies. Results: In the Chinese aged 20-59 years, the ICER of CHB antiviral treatment was 37 598.6 yuan (RMB) per QALYs and the ICERs were smaller in the low age groups, indicating that the antiviral treatment strategy is cost-effective and low age groups should be the priority population. The ICER of hepatitis B vaccination was -64 000.0 yuan (RMB) per QALYs, indicating that hepatitis B vaccination is cost saving. The CER of CHB antiviral treatment ranged from 731.8 to 1 813.3 yuan (RMB) per QALYs compared with hepatitis B vaccination, and the CER of CHB antiviral treatment was higher than that of hepatitis B vaccination in all age groups, indicating that hepatitis B vaccination would be more cost-effective than CHB antiviral treatment. The price of antiviral drug, entercavir, can influence the cost effectiveness of CHB antiviral treatment. If the price of entercavir declined half, CHB antiviral treatment would be cost-saving. The probability sensitivity analysis showed that people's willing to pay for CHB antiviral treatment should not be ignored, although the results of economics evaluation of CHB antiviral treatment were reliable. The results of affordability analysis indicated that the antiviral treatment strategy could not be implemented with the budget lower than 30 million yuan (RMB), the probability of implementing the strategy was 42.6% if the budget reaches 127 million yuan (RMB), and only when the budget reaches 269 million yuan (RMB), the goal of CHB antiviral treatment strategy can be fully realized. Conclusions: Although the strategy of CHB antiviral treatment as prevention in Chinese aged 20-59 years is cost-effective, it is not an appropriate public health measure due to the high cost. The cost effectiveness would be higher by conducting hepatitis B vaccination and then antiviral treatment in susceptible population.

[Promoting hepatitis B elimination and laying emphasis on its economics evaluation]

WHO has developed and issued global hepatitis B elimination program. Continuing hepatitis B immunization and conducting community based antiviral treatment for chronic hepatitis B are the most important strategies for hepatitis B elimination. According to the estimation of related cost by WHO, the cost of antiviral therapy would be very high. Great achievement has been made in hepatitis B immunization in China, but the prevalence of chronic hepatitis B is high. Elimination of hepatitis B needs a large amount of public resource, posing serious challenge to public health policy making. Economics research on hepatitis B prevention and treatment can provide evidence and technical support for hepatitis B elimination. In this column "Economic evaluations of hepatitis B" , the related articles in this issue summarize the progress in this research field, which is inspiring and encouraging.

[Advances in internal fixation for the treatment of extra-articular distal tibial fracture]

Extra-articular distal tibial fractures as a result of high-energy damage are often comminuted or displaced, frequently accompanied by severe soft tissue injuries.Poor blood supply and various complications make the treatment more difficult,affecting life quality of the patients.The main goals of the treatment are to abtain a healed,well-aligned fracture,functional range of motion of the ankle joint and minimizing complications.It is generally recommended that surgical treatment be performed in the proper context of local conditions to facilitate early functional exercise.Plate fixation and intramedullary nail fixation are the common options for closed fractures.This article focuses on the two treatment methods and some important auxiliary technologies in both domestic and foreign, hoping to provide some references for clinical treatment.

[Cost-effectiveness and affordability of strategy for preventing mother-to-child transmission of hepatitis B in China]

Objective: To evaluate the cost effectiveness of nationwide prevention of mother to child transmission (PMTCT) strategy for hepatitis B, and estimate the willing to pay and budget impacts on the PMTCT. Methods: The decision analytic Markov model for the PMTCT was constructed and a birth cohort of Chinese infants born in 2013 was used to calculate the cost-effectiveness of the PMTCT among them compared with those receiving no intervention. The parameters in the model were obtained from literatures of national surveys or Meta-analysis. The costs, cases of HBV-related diseases and quality-adjusted life-years (QALYs) were obtained from the societal and payer perspectives, respectively. The incremental cost-effectiveness ratio (ICER) was used as measures of strategy optimization. One-way and probability sensitivity analysis were performed to explore the uncertainty of the primary results. In addition, cost-effectiveness acceptability curve and cost-effectiveness affordability curves were drawn to illustrate the cost effectiveness threshold and financial budget of the PMTCT strategy. Results: The lifetime cost for PMTCT strategy was 4 063.5 yuan (RMB) per carrier, which was 37 829.7 yuan (RMB) lower compared with those receiving no intervention. Due to the strategy, a total of 24.516 1 QALYs per person would be gained, which was higher than that in those receiving no intervention. From societal perspective, the ICER was -59 136.6 yuan (RMB) per additional QALYs gained, indicating that the PMTCT is cost effective. The results were reliable indicated by one-way, multi-way and probability sensitivity analyses. By the CEAC, the willing to pay was much lower than the cost-effectiveness threshold. From the affordability curve of the PMTCT strategy, the annual budget ranged from 590.4 million yuan (RMB) to 688.8 million yuan (RMB), which was lower than the financial ability. Based on the results of cost-effectiveness affordability curves, the higher annual budget was determined, the higher probability of affordability for the PMTCT would be obtained under the same willing to pay state. Only when the annual budget reaches 688.8 million yuan (RMB), the goal of PMTCT would be fully realized. Conclusions: The PMTCT strategy in China was cost effective, and the cost is not beyond the financial budget needed and the willing to pay. The strategy, which is consistent with the global hepatitis B elimination efforts, should be conducted widely in China.

[Value of modified Killian's method in diagnosis of congenital pyriform sinus fistula]

Objective: To investigate the feasibility and significance of modified Killian(MK) method in the clinical diagnosis of congenital pyriform sinus fistula(CPSF) by electronic laryngoscopy. Methods: The following examinations were performed for 30 suspected cases of CPSF, including the traditional electronic laryngoscopy, MK examination(modified Killian position+ head rotation+ the Valsalva maneuver), barium swallow X-ray(BSX) and CT , and a prospective comparison among them were done. Patients were divided into two groups according to their age: young age group(≤14 years old) and older age group (>14 years old). The results of MK examination from the patients were analyzed and the positive diagnostic rates (PDR) between groups were compared by using χ(2) tests. Results: Sinuses in 20 of 30 patients were depicted from pyriform sinus in BSX, and the PDR was 66.7%(20/30). The PRD of CT was 83.3%(25/30). The presence of air bubbles around the upper lobe of the thyroid gland or at the inferomedial edge of cricothyroid joints, morphological changes of thyroid grand as well as pseudo-fistula formation on lower neck were detected clearly on CT. Comparing to the traditional electronic laryngoscopy, the effect of exposing piriform fossa fistula by MK examination is significant(χ(2)=17.05, P<0.05), with the PDR of 13.3%(4/30) and 76.7%(23/30) respectively. Nevertheless, comparing to BSX and CT, there were no statistically significant differences in the effect to diagnose CPSF (χ(2)=0.31, χ(2)=0.10 respectively, P>0.05). The PDR of MK in older group is significantly higher than younger group(χ(2)=6.68, P<0.05). Conclusions: MK examination can clearly reveal the hypopharyngeal anatomical structure and detect the sinus of CPSF .It could be a safe, feasible, convenient and economical method as an application in preoperative diagnosis and follow-up examination of clinical suspected CPSF.

Cost-effective way to reduce stimulant-abuse among gay/bisexual men and transgender women: a randomized clinical trial with a cost comparison

OBJECTIVES

A randomized controlled study was conducted with 422 homeless, stimulant-using gay/bisexual (G/B) men and 29 transgender women (n = 451) to assess two community-based interventions to reduce substance abuse and improve health: (a) a nurse case-managed program combined with contingency management (NCM + CM) versus (b) standard education plus contingency management (SE + CM).

STUDY DESIGN

Hypotheses tested included: a) completion of hepatitis A/B vaccination series; b) reduction in stimulant use; and c) reduction in number of sexual partners.

METHODS

A deconstructive cost analysis approach was utilized to capture direct costs associated with the delivery of both interventions. Based on an analysis of activity logs and staff interviews, specific activities and the time required to complete each were analyzed as follows: a) NCM + CM only; b) SE + CM only; c) time to administer/record vaccines; and d) time to receive and record CM visits. Cost comparison of the interventions included only staffing costs and direct cash expenditures.

RESULTS

The study outcomes showed significant over time reductions in all measures of drug use and multiple sex partners, compared to baseline, although no significant between-group differences were detected. Cost analysis favored the simpler SE + CM intervention over the more labor-intensive NCM + CM approach. Because of the high levels of staffing required for the NCM relative to SE, costs associated with it were significantly higher.

CONCLUSIONS

Findings suggest that while both intervention strategies were equally effective in achieving desired health outcomes, the brief SE + CM appeared less expensive to deliver.

[Bone conduction in tympanosclerosis patients and its changes after surgery for tympanosclerosis]

Objective:To investigate the bone conduction (BC) in tympanosclerosis patients and its changes after surgery for tympanosclerosis, as well as its possible causes.Method:Retrospectively analyzed 30 cases of tympanosclerosis patients.Result:Before surgery, the average BC of the operated ear was (21.06±8.88) dBHL, the average BC of the healthy side was (16.78±8.97) dBHL, the difference had a statistical significance (t= 3.072, P< 0.01). The BC threshold, air conduction (AC) and ABG were significantly lower after operation. Preoperative BC at 2 000 Hz was the highest threshold (25.17±10.95) dBHL, and the postoperative decrease of BC thresholds at 500 Hz, 1 000 Hz and 2 000 Hz were statistically significant (P< 0.05 or P< 0.01). Tympanoplasty with mastoidectomy for BC threshold improvement was better than only tympanoplasty (P< 0.05)Conclusion:Tympanosclerosis leads to elevated BC threshold. Removal of tympanosclerosis lesions together with the removal of the lesions in antrum and mastoid and the reconstruction of sound conduction structures not only improve AC hearing and shorten ABG, but also improve postoperative BC hearing significantly.

Epitaxial thin films of pyrochlore iridate Bi2+xIr2-yO7-δ: structure, defects and transport properties

While pyrochlore iridate thin films are theoretically predicted to possess a variety of emergent topological properties, experimental verification of these predictions can be obstructed by the challenge in thin film growth. Here we report on the pulsed laser deposition and characterization of thin films of a representative pyrochlore compound Bi₂Ir₂O₇. The films were epitaxially grown on yttria-stabilized zirconia substrates and have lattice constants that are a few percent larger than that of the bulk single crystals. The film composition shows a strong dependence on the oxygen partial pressure. Density-functional-theory calculations indicate the existence of Bi_Ir antisite defects, qualitatively consistent with the high Bi: Ir ratio found in the films. Both Ir and Bi have oxidation states that are lower than their nominal values, suggesting the existence of oxygen deficiency. The iridate thin films show a variety of intriguing transport characteristics, including multiple charge carriers, logarithmic dependence of resistance on temperature, antilocalization corrections to conductance due to spin-orbit interactions, and linear positive magnetoresistance.

[Prevalence of hearing disorders in China: a population-based survey in four provinces of China]

Objective: To investigate the prevalence, severity of hearing disorders and demographics of people with hearing disorders based on the whole population in Jilin, Guangdong, Shannxi and Gansu provinces in China. Methods: According to " WHO Ear and Hearing Disorders Survey Protocol" , 144 clusters were chosen with probability proportional sampling(PPS) method from the four provinces covering 194, 688, 061 residents. Audiological test, otological examination and questionnaire surveying were conducted for all samples from August, 2014 to September, 2015. The hearing disorders were classified according to WHO criteria and classification. Results: Among 47 511 targeted residents, 45, 052 individuals (94.82% response rate) participated in the survey. The standardized prevalence rates of hearing disorders and disabling hearing disorders were 15.84 % and 5.17 % respectively. Almost 50% of people with hearing disorders had no awareness of it or its starting time. There was significant difference in the prevalence among people of different ages, genders, occupations, provinces, marital status and education levels. The prevalence of hearing disorders increased significantly as age grew. People above 60 years old occupied 55.31% of the total hearing disorders. The prevalence of hearing disorders among male, people of low education and those who lost husband or wife, as well as workers and farmers was relatively higher. Conclusions: The prevalence of hearing disorders is high, and hearing disorders are " invisible" . Demographics and socioeconomic factors significantly influence the prevalence of hearing disorders.

[Cost-effectiveness and cost-benefit analysis on strategy for preventing mother-to-child transmission of hepatitis B virus]

OBJECTIVE

Through cost-benefit analysis (CBA), cost-effectiveness analysis (CEA) and quantitative optimization analysis to understand the economic benefit and outcomes of strategy regarding preventing mother-to-child transmission (PMTCT) on hepatitis B virus.

METHODS

Based on the principle of Hepatitis B immunization decision analytic-Markov model, strategies on PMTCT and universal vaccination were compared. Related parameters of Shenzhen were introduced to the model, a birth cohort was set up as the study population in 2013. The net present value (NPV), benefit-cost ratio (BCR), incremental cost-effectiveness ratio (ICER) were calculated and the differences between CBA and CEA were compared.

RESULTS

A decision tree was built as the decision analysis model for hepatitis B immunization. Three kinds of Markov models were used to simulate the outcomes after the implementation of vaccination program. The PMTCT strategy of Shenzhen showed a net-gain as 38 097.51 Yuan/per person in 2013, with BCR as 14.37. The universal vaccination strategy showed a net-gain as 37 083.03 Yuan/per person, with BCR as 12.07. Data showed that the PMTCT strategy was better than the universal vaccination one and would end with gaining more economic benefit. When comparing with the universal vaccination program, the PMTCT strategy would save 85 100.00 Yuan more on QALY gains for every person. The PMTCT strategy seemed more cost-effective compared with the one under universal vaccination program. In the CBA and CEA hepatitis B immunization programs, the immunization coverage rate and costs of hepatitis B related diseases were the most important influencing factors. Outcomes of joint-changes of all the parameters in CEA showed that PMTCT strategy was a more cost-effective.

CONCLUSIONS

The PMTCT strategy gained more economic benefit and effects on health. However, the cost of PMTCT strategy was more than the universal vaccination program, thus it is important to pay attention to the process of PMTCT strategy and the universal vaccination program. CBA seemed suitable for strategy optimization while CEA was better for strategy evaluation. Hopefully, programs as combination of the above said two methods would facilitate the process of economic evaluation.

p-Type transition-metal doping of large-area MoS2 thin films grown by chemical vapor deposition

Two-dimensional transition metal dichalcogenides (e.g. MoS₂) have recently emerged as a promising material system for electronic and optoelectronic applications. A major challenge for these materials, however, is to realize bipolar electrical transport properties (i.e. both p-type and n-type conduction), which is critical for enhancing device performance and functionalities. Here, we demonstrate the transition metal zinc as a p-type dopant in the otherwise n-type MoS₂, through systematic characterizations of large area Zn-doped MoS₂ thin films grown by a one-step chemical vapor deposition (CVD) approach. Raman characterization and X-ray photoelectron spectroscopy studies identified millimeter-scale, monolayer films with 1-2% Zn as dopants. Zinc doping suppresses n-type conductivity in MoS₂ and shifts its Fermi level downwards. The stability and p-type nature of Zn dopants were further confirmed by density-functional-theory calculations of formation energies and electronic band structures. The electrical transport properties of Zn-MoS₂ films can be influenced by stoichiometry, and p-type gate transfer characteristics were realized by thermal treatment under a sulfur atmosphere. Our work highlights transition-metal doping followed by sulfur vacancy elimination in CVD grown films as a promising route for achieving large area p-type transition metal dichalcogenide films that are essential for practical applications in electronics and optoelectronics.

MiR-214 regulates oral cancer KB cell apoptosis through targeting RASSF5

Ras association domain family member 5 (RASSF5), a member of the Ras association domain family, induces cell apoptosis by phosphorylating FOXO3a, which triggers target gene BIM (pro-apoptotic factor) activation. MiR-214 is overexpressed in oral cancer tissue, indicating its possible involvement in oral cancer pathogenesis. Bioinformatics analysis has revealed a complimentary sequence between miR-214 and the 3'-UTR of RASSF5 mRNA. However, whether miR-124 regulates RASSF5 in oral cancer remains poorly understood. We aimed to investigate the role of miR-214 in RASSF5 expression regulation in oral cancer. Tumor and paracarcinoma tissues were obtained from 48 oral cancer patients to examine miR-214 and RASSF5 expression. The relationship between miR-214 and RASSF5 was investigated by dual luciferase reporter gene assay. Oral cancer KB cells were cultured in vitro and divided into inhibitor NC, miR-214 inhibitor, Scramble-pMD18, RASSF5-pMD18, and miR-214 inhibitor + RASSF5-pMD18 groups. Caspase 3 activity, cell apoptosis, and total protein expression were measured by spectrophotometry, flow cytometry, and western blot, respectively. MiR-214 expression was significantly increased, while that of RASSF5 decreased in oral cancer tumor tissues compared to paracarcinoma tissues. Luciferase assay showed that miR-214 suppressed RASSF5 expression by targeting its 3'-UTR. Down-regulation of miR-214 and/or enhancement of RASSF5 expression markedly increased FOXO3a phosphorylation, BIM expression, caspase 3 activity, and apoptosis. In conclusion, miR-214 expression was elevated and RASSF5 was down-regulated in oral cancer. Moreover, miR-214 regulated KB cell apoptosis through targeted inhibition of RASSF5 expression, FOXO3a phosphorylation, and BIM expression, suggesting its possible application as a novel therapeutic oral cancer target.

[Changes of soil physical properties during the conversion of cropland to agroforestry system]

To provide theoretical basis for modeling and managing agroforestry systems, the influence of conversion of cropland to agroforestry system on soil physical properties was investigated via a walnut (Juglans regia)-wheat (Triticum aestivum) intercropping system, a wide spreading local agroforestry model in northern Weihe River of loess area, with the walnut and wheat monoculture systems as the control. The results showed that the improvement of the intercropping system on soil physical properties mainly appeared in the 0-40 cm soil layer. The intercropping system could prevent soil bulk density rising in the surface soil (0-20 cm), and the plow pan in the 20-40 cm soil layer could be significantly alleviated. The intercropping system had conti-nuous improvement on soil field capacity in each soil layer with the planting age increase, and the soil field capacity was higher than that of each monoculture system in each soil layer (except 20-40 cm soil layer) since the 5th year after planting. The intercropping system had continuous improvement on soil porosity in each soil layer, but mainly in the 0-20 and 20-40 cm soil layer, and the ratio of capillary porosity was also improved. The soil bulk density, field capacity and soil porosity obtained continuous improvement during the conversion of cropland to agroforestry system, and the improvement on soil physical properties was stronger in shallow soil layer than in deep soil.

[Expression of hypoxia-inducible factor 1α in gastric cancer and its clinical signficance]

OBJECTIVE

To explore the expression level and location of hypoxia-inducible factor 1α (HIF-1α) in gastric cancer (GC) tissues and their relationship with clinicopathological features and clinical outcomes.

METHODS

From July to September 2015, 27 pairs of fresh paired GC tissues and adjacent normal tissues were gathered from the Eighth Department of General Surgery of the First Affiliated Hospital of Anhui Medical University. Quantitative real-time PCR (qRT-PCR) and Western blot were performed to detect the expression of HIF-1α mRNA and protein in these tissues. A total of 191 GC tissues and 46 randomly selected adjacent normal gastric tissues were consecutively collected between December 2006 and September 2008 from Department of General Surgery of the same hospital. Immunohistochemistry were performed on them to detect the expression of HIF-1α and CD34[described in terms of microvessel density (MVD)], and correlation of different locations of HIF-1α (in cytoplasm or nucleus) with MVD, clinicopathological features, and clinical prognosis was analyzed.

RESULTS

The average relative expression level of HIF-1α mRNA in GC tissues (0.625±0.170) was significantly higher than in normal adjacent tissues (0.218±0.036, t=2.336, P=0.023) by qRT-PCR. From the results of Western blot, the expression level of HIF-1α protein increased in GC tissues compared with its corresponding normal tissues. Immunohistochemistry results revealed that positive HIF-1α staining was observed in 67.54% GC tissues and 45.65% normal tissues, with significant difference (P=0.006). And 35.08% in GC and 45.65% in normal tissues were cytoplasmic positive (P=0.138); while 37.17% in GC and only 2.17% in normal tissues were nuclear positive, with significant difference (P<0.001). High differentiation group and TNM clinical early stage (Ⅰ+ Ⅱ) group had significantly higher cytoplasmic HIF-1α expression positive rate compared with low differentiation group (P=0.008) and TNM clinical intermediate-advanced stage (Ⅲ+ Ⅳ) group (P=0.019); whereas low differentiation group had significantly higher nuclear HIF-1α expression positive rate compared with high differentiation group (P=0.043). The mean MVD in the nuclear HIF-1α positive GC group (115.6 ± 7.8) was higher than that in the cytoplasmic HIF-1α positive GC group (93.1±7.5, t=2.077, P=0.040). The median follow-up time was 56(3-81)months. Kaplan-Meier survival analysis and Log-Rank test results showed that nuclear HIF-1α positive patients had a shorter survival time (median 45 months) than cytoplasmic HIF-1α positive patients (median 64 months, P<0.001). Multivariate Cox regression analysis revealed that differentiation (HR=1.713; 95% CI: 1.019-2.882), depth of invasion (tumor stage, HR=6.137; 95% CI: 1.832-20.556) and lymph node metastasis (HR=2.788; 95% CI: 1.313-5.920) were independent prognostic factors for GC (all P<0.05).

CONCLUSION

Different location of HIF-1α protein may be realted to the tumorigenesis and progression of GC, and may become a potential prognostic indicator of GC.

[A survey on tyrosine kinase inhibitor treatment in patients with chronic myeloid leukemia in China: from patients'perspective]

OBJECTIVES

To assess tyrosine kinase inhibitor (TKI) treatment status in patients with chronic myeloid leukemia (CML) in China and analyze the response-associated factors.

METHODS

From May to November in 2014, anonymous questionnaires were distributed to adult CML patients who were receiving TKI treatment all over China.

RESULTS

1 038 questionnaires were collected, 949 questionnaires were evaluable. Of the 949 evaluable respondents, 549 (58%) were male with the median age of 41 years (range, 18 to 88 years). 623 (66%) respondents lived in an urban area and 449 (47%) had an education level ≥ a bachelor degree. 888 (94%) respondents were in the chronic phase at diagnosis, and 690 (78%) of them started TKI treatment within one year after diagnosis. 794 (84%) respondents were on imatinib, 768 (81%) on the branded. With a median TKI treatment duration of 3 years (range, <1 to 13 years), 708 of 834 (85%) evaluable respondents achieved Ph- negative (i.e. complete cytogenetic response, CCyR), and 497 of 859 (46% ) BCR- ABL negative (i.e. complete molecular response, CMR). Multivariate analyses showed that female (OR=1.8, 95% CI 1.1-2.8,P=0.019 andOR=1.5, 95% CI 1.1-2.0,P=0.015), TKI treatment duration >3 years (OR=4.1, 95% CI 2.6- 6.5,P<0.001 andOR=3.7, 95% CI 2.7- 5.1,P< 0.001) and imatinib taken (OR=2.1, 95% CI 1.2-3.7,P=0.007 andOR=3.3, 95% CI 2.1-5.1,P<0.001) were factors affecting achieving both CCyR and CMR. In addition, higher education level (OR=2.0, 95% CI 1.3- 3.1,P=0.003), starting TKI treatment <1 year (OR=2.4, 95% CI 1.5- 3.8,P<0.001) and branded drugs received (OR=2.4, 95% CI 1.4- 4.0,P=0.001) were factors affecting achieving a CCyR. In 884 respondents, 534 (62%) reported " heavy financial burden" as the biggest treatment impediment, only 152 (17%) reported " poor quality of life related to adverse effects of TKI".

CONCLUSIONS

The survey showed that majority of the Chinese CML patients received imatinib as a TKI therapy, and most of the patients achieved satisfied responses by TKI. Financial burden became the major obstacle during TKI treatment.

Diameter dependent thermoelectric properties of individual SnTe nanowires

The lead-free compound tin telluride (SnTe) has recently been suggested to be a promising thermoelectric material. In this work, we report on the first thermoelectric study of individual single-crystalline SnTe nanowires with different diameters ranging from ∼218 to ∼913 nm. Measurements of thermopower S, electrical conductivity σ and thermal conductivity κ were carried out on the same nanowires over a temperature range of 25-300 K. While the electrical conductivity does not show a strong diameter dependence, the thermopower increases by a factor of two when the nanowire diameter is decreased from ∼913 nm to ∼218 nm. The thermal conductivity of the measured NWs is lower than that of the bulk SnTe, which may arise from the enhanced phonon - surface boundary scattering and phonon-defect scattering. Temperature dependent figure of merit ZT was determined for individual nanowires and the achieved maximum value at room temperature is about three times higher than that in bulk samples of comparable carrier density.

Single crystalline nanostructures of topological crystalline insulator SnTe with distinct facets and morphologies

Topological crystalline insulators (TCIs) are a new class of topological materials that possess unique metallic surface states protected by crystalline mirror symmetry. Their topological surface properties are expected to strongly depend on the surface orientation. By combining density functional theory (DFT) calculations and synthesis experiments, we demonstrate the controlled growth of single crystalline nanostructures of the prototypical TCI SnTe with distinct facets and morphologies. Our calculations suggest that the excess energy of the {111} surfaces can be either higher or lower than that of the {100} surfaces, depending on the stoichiometry, while the {110} is always higher than the {100}. In our synthesis experiment, we qualitatively controlled the stoichiometry by tailoring the growth temperature and obtained two types of single crystalline nanowires: smooth nanowires dominated by {100} facets at high temperatures and zigzag nanowires composed of both {100} and {111} surfaces at low temperatures. Notably, there is no {110} facet in our nanostructures, strongly supporting the DFT calculations. Our device fabrication and electrical characterizations suggest that both types of nanowires are suitable for transport studies of topological surface states.

Accelerated partial-breast irradiation using intensity-modulated proton radiotherapy: do uncertainties outweigh potential benefits?

OBJECTIVE

Passive scattering proton beam (PSPB) radiotherapy for accelerated partial-breast irradiation (APBI) provides superior dosimetry for APBI three-dimensional conformal photon radiotherapy (3DCRT). Here we examine the potential incremental benefit of intensity-modulated proton radiotherapy (IMPT) for APBI and compare its dosimetry with PSPB and 3DCRT.

METHODS

Two theoretical IMPT plans, TANGENT_PAIR and TANGENT_ENFACE, were created for 11 patients previously treated with 3DCRT APBI and were compared with PSPB and 3DCRT plans for the same CT data sets. The impact of range, motion and set-up uncertainties as well as scanned spot mismatching between fields of IMPT plans was evaluated.

RESULTS

IMPT plans for APBI were significantly better regarding breast skin sparing (p<0.005) and other normal tissue sparing than 3DCRT plans (p<0.01) with comparable target coverage (p=ns). IMPT plans were statistically better than PSPB plans regarding breast skin (p<0.002) and non-target breast (p<0.007) in higher dose regions but worse or comparable in lower dose regions. IMPT plans using TANGENT_ENFACE were superior to that using TANGENT_PAIR in terms of target coverage (p<0.003) and normal tissue sparing (p<0.05) in low-dose regions. IMPT uncertainties were demonstrated for multiple causes. Qualitative comparison of dose-volume histogram confidence intervals for IMPT suggests that numeric gains may be offset by IMPT uncertainties.

CONCLUSION

Using current clinical dosimetry, PSPB provides excellent dosimetry compared with 3DCRT with fewer uncertainties compared with IMPT.

ADVANCES IN KNOWLEDGE

As currently delivered in the clinic, PSPB planning for APBI provides as good or better dosimetry than IMPT with less uncertainty.

Histoplasmosis and subcutaneous nodules in a kidney transplant recipient: erythema nodosum versus fungal panniculitis

Erythema nodosum (EN)-like lesions are a rare occurrence after solid organ transplantation. Differential diagnosis includes infective panniculitis, which can be a feature of progressive disseminated histoplasmosis (PDH), an uncommon but severe form affecting primarily immunocompromised hosts. We report on a fatal case of PDH, which presented as fungal panniculitis masquerading as EN in a renal allograft recipient 25 years after transplantation. We discuss the clinical, histopathological, and microbiological characteristics of this rare complication, with focus on its distinction from EN. This case emphasizes the central role of biopsy in transplant recipients presenting with cutaneous lesions, and the importance of clinicopathologic correlation and complementary microbiological investigations.

Effects of pH adjustment with phosphates on attributes and functionalities of normal and high pH beef

Longissimus dorsi muscles from six normal- and six high-ultimate pH bulls were selected for fine mincing and subsequent pH adjustment with acid and alkaline pyrophosphate. Four pH treatments were prepared: initially high remains high (mean of pH 6.37), high becomes normal (5.62); initially normal remains normal (5.65), and normal becomes high (6.21). The addition level of phosphate as P(2)O(5) was the same in all replicates. Before pH adjustment, colour and water holding capacity (WHC) values were strongly affected by higher (initial) pH in expected ways: darker, lower chroma, higher capacity. After pH adjustment, these values were affected only by the final pH, not the initial pH (the pH history). Total protein solubility was likewise affected by final pH but not initial pH. In contrast, the combination high initial pH-high final pH improved sarcoplasmic protein solubility by 20% over the combination normal initial pH-high final pH. Sarcoplasmic protein solubility is an indicator of strain required to fracture cooked batters made from the minced meats; in the event, the rank order of the four treatments for strain-to-fracture matched that of sarcoplasmic protein solubility. Statistically, sarcoplasmic protein solubility and strain-to-fracture were both affected by initial pH (P<0.01) and final pH (P<0.001). However, stress required to fracture cooked batters was entirely controlled by initial pH (P<0.01). In other words, the stress-to-fracture advantage of initially high pH meat was not matched by upward pH adjustment of initially normal pH meat. Emulsion stability, which is better with higher pH meat, was affected by initial and final pH (both P<0.01). Cook yield, like WHC of pH-adjusted raw meat, was more due to final pH than initial pH, similarly cooked batter colour, whereas final pH had a significant effect on quality attributes (generally better when higher). An initially high pH history conferred an enduring advantage on three important batter attributes, stress-to-fracture, strain-to-fracture, and emulsion stability. Therefore, prior exposure of beef to normal pH conditions (pH 5.4-5.7) renders it less useful as a manufacturing grade product.

Prospective evaluation of a matrix-assisted laser desorption ionization-time of flight mass spectrometry system in a hospital clinical microbiology laboratory for identification of bacteria and yeasts: a bench-by-bench study for assessing the impact on time to identification and cost-effectiveness

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has been found to be an accurate, rapid, and inexpensive method for the identification of bacteria and yeasts. Previous evaluations have compared the accuracy, time to identification, and costs of the MALDI-TOF MS method against standard identification systems or commercial panels. In this prospective study, we compared a protocol incorporating MALDI-TOF MS (MALDI protocol) with the current standard identification protocols (standard protocol) to determine the performance in actual practice using a specimen-based, bench-by-bench approach. The potential impact on time to identification (TTI) and costs had MALDI-TOF MS been the first-line identification method was quantitated. The MALDI protocol includes supplementary tests, notably for Streptococcus pneumoniae and Shigella, and indications for repeat MALDI-TOF MS attempts, often not measured in previous studies. A total of 952 isolates (824 bacterial isolates and 128 yeast isolates) recovered from 2,214 specimens were assessed using the MALDI protocol. Compared with standard protocols, the MALDI protocol provided identifications 1.45 days earlier on average (P < 0.001). In our laboratory, we anticipate that the incorporation of the MALDI protocol can reduce reagent and labor costs of identification by $102,424 or 56.9% within 12 months. The model included the fixed annual costs of the MALDI-TOF MS, such as the cost of protein standards and instrument maintenance, and the annual prevalence of organisms encountered in our laboratory. This comprehensive cost analysis model can be generalized to other moderate- to high-volume laboratories.

Pharmacokinetics, tissue distribution, and metabolism of novel DNA topoisomerase I inhibitor yuanhuacine in rabbit

A liquid chromatography/tandem mass spectrometry method was developed and validated for the quantitative determination of yuanhuacine (YHC), a daphne diterpene ortho-ester anticancer agent, and identification of its metabolites. Pharmacokinetic behaviour, tissue distribution, and metabolism were investigated in rabbit. YHC plasma data best fitted to a two-compartment model and were characterized by an elimination half-life t(1/2)(beta) of 11.1 h following intravenous administration. Tissue distribution studies did not identify any tissues having a high affinity for YHC. The main metabolites are proposed to be M392I, M392II, and M390, resulting from the ortho-ester group and aromatic ester bond being cleaved off simultaneously during Phase I metabolism. This investigation contributes to an understanding of the metabolism of daphne diterpene ortho-esters.

Anti-angiogenic factors and pre-eclampsia in type 1 diabetic women

AIMS/HYPOTHESIS

Elevated anti-angiogenic factors such as soluble fms-like tyrosine kinase 1 (sFlt1), a soluble form of vascular endothelial growth factor receptor, and endoglin, a co-receptor for TGFbeta1, confer high risk of pre-eclampsia in healthy pregnant women. In this multicentre prospective study, we determined levels of these and related factors in pregnant women with type 1 diabetes, a condition associated with a fourfold increase in pre-eclampsia.

METHODS

Maternal serum sFlt1, endoglin, placental growth factor (PlGF) and pigment epithelial derived factor were measured in 151 type 1 diabetic and 24 healthy non-diabetic women at each trimester and at term.

RESULTS

Approximately 22% of the diabetic women developed pre-eclampsia, primarily after their third trimester visit. In women with pre-eclampsia (diabetic pre-eclampsia, n = 26) vs those without hypertensive complications (diabetic normotensive, n = 95), significant changes in angiogenic factors were observed, predominantly in the early third trimester and prior to clinical manifestation of pre-eclampsia. Serum sFlt1 levels were increased approximately twofold in type 1 diabetic pre-eclampsia vs type 1 diabetic normotensive women at the third trimester visit (p < 0.05) and the normal rise of PlGF during pregnancy was blunted (p < 0.05). Among type 1 diabetic women, third trimester sFlt1 and PlGF were inversely related (r(2) = 42%, p < 0.0001). Endoglin levels were increased significantly in the diabetic group as a whole vs the non-diabetic group (p < 0.0001).

CONCLUSIONS/INTERPRETATION

Higher sFlt1 levels, a blunted PlGF rise and an elevated sFlt1/PlGF ratio are predictive of pre-eclampsia in pregnant women with type 1 diabetes. Elevated endoglin levels in women with type 1 diabetes may confer a predisposition to pre-eclampsia and may contribute to the high incidence of pre-eclampsia in this patient group.

Increased serum pigment epithelium-derived factor is associated with microvascular complications, vascular stiffness and inflammation in Type 1 diabetes

AIMS

To determine in Type 1 diabetes patients if levels of pigment epithelium-derived factor (PEDF), an anti-angiogenic, anti-inflammatory and antioxidant factor, are increased in individuals with complications and positively related to vascular and renal dysfunction, body mass index, glycated haemoglobin, lipids, inflammation and oxidative stress.

METHODS

Serum PEDF levels were measured by ELISA in a cross-sectional study of 123 Type 1 diabetic patients (71 without and 52 with microvascular complications) and 31 non-diabetic control subjects. PEDF associations with complication status, pulse-wave analysis and biochemical results were explored.

RESULTS

PEDF levels [geometric mean (95% CI)] were increased in patients with complications 8.2 (7.0-9.6) microg/ml, vs. complication-free patients [5.3 (4.7-6.0) microg/ml, P < 0.001] and control subjects [5.3 (4.6-6.1) microg/ml, P < 0.001; anova between three groups, P < 0.001], but did not differ significantly between control subjects and complication-free patients (P > 0.05). In diabetes, PEDF levels correlated (all P < 0.001) with systolic blood pressure (r = 0.317), pulse pressure (r = 0.337), small artery elasticity (r = -0.269), glycated haemoglobin (r = 0.245), body mass index (r = 0.362), renal dysfunction [including serum creatinine (r = 0.491), cystatin C (r = 0.500)], triglycerides (r = 0.367), and inflammation [including log(e)C-reactive protein (CRP; r = 0.329), and soluble vascular cell adhesion molecule-1 (r = 0.363)]. Age, blood urea nitrogen, systolic blood pressure, pulse pressure and log(e)CRP correlated with PEDF levels in control subjects (all P < 0.04). PEDF levels were not significantly correlated with measures of oxidative stress: isoprostanes, oxidized low-density lipoprotein or paraoxonase-1 activity. On stepwise linear regression analysis (all subjects), independent determinants of PEDF levels were renal function, triglycerides, inflammation, small artery elasticity and age (r(2) = 0.427).

CONCLUSIONS

In Type 1 diabetes, serum PEDF levels are associated with microvascular complications, poor vascular health, hyperglycaemia, adiposity and inflammation.

Association of intercellular adhesion molecule 1 polymorphisms with retinopathy in Chinese patients with Type 2 diabetes

AIMS

To investigate the relationship of the K469E and G241R polymorphisms of the intercellular adhesion molecule 1 (ICAM-1) gene with diabetic retinopathy in Chinese patients with Type 2 diabetes mellitus.

PATIENTS AND METHODS

One hundred and seventy-two Chinese patients with Type 2 diabetes and 80 normal control subjects were recruited. Patients with diabetes were placed into two groups: the diabetic retinopathy (DR) group and the non-diabetic retinopathy (NDR) group. The DR group was subdivided into those with proliferative retinopathy (PDR) and non-proliferative retinopathy (NPDR). Genomic DNA was prepared using the hydroxybenzene-chloroform extraction method. Genotypes and alleles were detected by polymerase chain reaction-heteroduplex-single-strand conformation polymorphism (PCR-HA-SSCP) analysis combined with gene sequencing.

RESULTS

The patients with retinopathy had an increased frequency of the K469K genotype compared with both the patients without retinopathy and the control subjects (61.4 vs. 40.0 and 35.0%, respectively; chi(2) = 8.280 and 13.952, respectively; P < 0.05). The frequency of the K allele in the DR group was higher than in the NDR group and control subjects (75.4 vs. 58.8 and 61.3%, respectively; chi(2) = 9.693 and 11.219, respectively; P < 0.05). Genotype and allele frequencies were similar in the NDR group and control subjects, and in the PDR and NPDR groups.

CONCLUSION

The ICAM-1 gene K469E polymorphism is associated with diabetic retinopathy in Chinese patients with Type 2 diabetes. Patients with the K469K genotype were more likely to have diabetic retinopathy than patients with the K469E or E469E genotype.

Technical Note: A monoclonal antibody-based immunoassay for determination of ractopamine in swine feeds1

An ELISA was developed for routine screening of ractopamine in swine feeds. Swine feed samples were extracted and purified, and the aqueous portion of the extract was analyzed for ractopamine using ELISA and confirmed by HPLC. For swine complex feeds containing ractopamine at 2.5 to 40 mg/kg, the average recoveries ranged from 73.1 to 86.5% by ELISA and 81.9 to 98.2% by HPLC. For the swine supplement containing ractopamine at 50 to 400 mg/kg, the average recoveries were 105.5 to 111.4% by ELISA and 89.1 to 92.9% by HPLC. The limit of detection was 0.24 microg/g by ELISA and 0.48 microg/g by HPLC, respectively. Results from the swine complex feeds (P = 0.009) and the supplement (P = 0.005) using ELISA and HPLC were not highly correlated. The ELISA was more sensitive and rapid and less expensive than the HPLC method and could be used for ractopamine screening in swine feeds before confirmation and quantification by other methods, such as HPLC.

Photorealistic virtual anatomy based on Chinese Visible Human data

Virtual reality based learning of human anatomy is feasible when a database of 3D organ models is available for the learner to explore, visualize, and dissect in virtual space interactively. In this article, we present our latest work on photorealistic virtual anatomy applications based on the Chinese Visible Human (CVH) data. We have focused on the development of state-of-the-art virtual environments that feature interactive photo-realistic visualization and dissection of virtual anatomical models constructed from ultra-high resolution CVH datasets. We also outline our latest progress in applying these highly accurate virtual and functional organ models to generate realistic look and feel to advanced surgical simulators.

X-irradiation reduces lesion scarring at the contusion site of adult rat spinal cord

Spinal cord injury (SCI) results in cell death and tissue destruction, and ultimately cavitation followed by the formation of lesion scars at the injury site. The lesion scars include an astrocytic component (glial scar) and a fibroblastic component (connective tissue scar). The purpose of the present study is to determine if X-irradiation could minimize the formation of lesion scars and reduce the levels of chondroitin sulfate proteoglycans (CSPGs) in the contusion SCI model of the adult rat. Two weeks after SCI, a connective tissue scar formed at the injury site consisting primarily of fibroblasts and exhibits strong CSPG immunoreactivity. The fibroblasts might originate from the connective tissue of pia mater or arachnoid mater. At the same time, reactive astrocytes in the spared tissue accumulate surrounding the lesion cavity to form a thick glial scar with significant enhancement of glial fibrillary acidic protein (GFAP) and CSPG immunoreactivity. After X-irradiation (40 Gy) of the injury site 2 days post-injury, that results in an attenuated dose to the lesion, the connective tissue scar was not observed, and accordingly, almost no CSPG immunoreactivity was detected at this area. Meanwhile, the glial scar and its CSPG immunoreactivity were prominently reduced. X-irradiation did not show significant improvement in locomotor recovery, but resulted in a slight delay of body weight recovery following injury. This preparative treatment could be used to reduce secondary scarring in the lesion resulting in an enriched site for further treatment such as growth related transplantation.

The pre-styloid compartment of the parapharyngeal space: a three-dimensional digitized model based on the Chinese Visible Human

To build a digitized visible model of the parapharyngeal space of the Chinese Visible Human and to provide a sectional anatomic basis for radiological and clinical diagnosis of the parapharyngeal space, sectional anatomy data of the parapharyngeal space were selected from the Chinese Visible Human male and female to compare with MR imaging findings in the axial planes. From these data the parapharyngeal space and surrounding structures were segmented. They were then reconstructed in three dimensions on PC. In the axial planes of the sectional anatomy and MR imaging, the shape, content and relations of the parapharyngeal space were clearly displayed and the dominant plane for showing the parapharyngeal space was elicited. The three-dimensional reconstructed images displayed perfectly the anatomic relationships of the parapharyngeal space, parotid, muscles, mandible and vessels. All reconstructed structures can be displayed singly, in groups or as a whole; any diameter or angle of the reconstructed structures can be easily measured. The Chinese Visible Human male and female data set can provide complete and accurate data. The digitized model of the parapharyngeal space and its surroundings offers unique insights into the complex anatomy of the area, providing morphologic data for imaging diagnosis and surgery of the parapharyngeal space.

Plasminogen kringle 5 reduces vascular leakage in the retina in rat models of oxygen-induced retinopathy and diabetes

AIMS/HYPOTHESIS

Retinal vascular leakage is an early pathological feature in diabetic retinopathy and can lead to macular oedema and loss of vision. Previously we have shown that plasminogen kringle 5 (K5), an angiogenic inhibitor, inhibits retinal neovascularisation in the rat model of oxygen-induced retinopathy (OIR). The purpose of this study was to examine the effect of K5 on vascular leakage in the retina.

METHODS

Neonatal rats were exposed to hyperoxia to induce OIR. Diabetes was induced in adult rats by injecting streptozotocin. Vascular permeability was measured by Evans blue method. Expression of vascular endothelial growth factor (VEGF) was evaluated using immunohistochemistry and western blot analysis.

RESULTS

Rats with OIR and diabetes showed abnormal vascular hyperpermeability in the retina and iris. Intravitreal injection of K5, reduced vascular permeability in both animal models, but did not affect permeability in normal rats. K5 reduced vascular permeability at doses substantially lower than that required for inhibition of retinal neovascularisation. The K5-induced reduction in vascular permeability correlated with its down-regulation of VEGF expression in the retina. Moreover, K5 inhibited IGF-1-induced hyperpermeability, which is known to arise through up-regulation of endogenous VEGF expression. However, K5 had no effect on the hyperpermeability induced by injection of exogenous VEGF.

CONCLUSIONS/INTERPRETATION

Very low doses of K5 reduce pathological vascular leakage in the retina. K5 thus has therapeutic potential in the treatment of diabetic macular oedema. This effect can be ascribed, at least in part, to the down-regulation of endogenous VEGF expression.

Kallikrein-binding protein inhibits retinal neovascularization and decreases vascular leakage

AIMS/HYPOTHESIS

Kallikrein-binding protein (KBP) is a serine proteinase inhibitor (serpin). It specifically binds to tissue kallikrein and inhibits kallikrein activity. Our study was designed to test its effects on retinal neovascularization and vascular permeability.

METHODS

Endothelial cell proliferation was determined by [(3)H] thymidine incorporation assay and apoptosis quantified by Annexin V staining and flow cytometry. Effect on retinal neovascularization was determined by fluorescein angiography and count of pre-retinal vascular cells in an oxygen-induced retinopathy (OIR) model. Vascular permeability was assayed by the Evans blue method. Vascular endothelial growth factor (VEGF) was measured by Western blot analysis and ELISA.

RESULTS

Kallikrein-binding protein specifically inhibited proliferation and induced apoptosis in retinal capillary endothelial cells. Intravitreal injection of KBP inhibited retinal neovascularization in an OIR model. Moreover, KBP decreased vascular leakage in the retina, iris and choroid in rats with OIR. Blockade of kinin receptors by specific antagonists showed significantly weaker inhibition of endothelial cells, when compared to that of KBP, suggesting that the anti-angiogenic activity of KBP is not through inhibiting kallikrein activity or kinin production. KBP competed with (125)I-VEGF for binding to endothelial cells and down-regulated VEGF production in endothelial cells and in the retina of the OIR rat model.

CONCLUSION/INTERPRETATION

Kallikrein-binding protein is a multi-functional serpin, and its vascular activities are independent of its interactions with the kallikrein-kinin system. Inhibition of VEGF binding to its receptors and down-regulation of VEGF expression could represent a mechanism for the vascular activities of KBP.

A study on the sectional anatomy of the oculomotor nerve and its related blood vessels with plastination and MRI

To obtain normal images and sectional anatomical data of the oculomotor nerve and its related arteries, the optimal angles and the length of intracisternal segment of the oculomotor nerve were measured on MPR images. Meanwhile, the relationships between the nerve and the basilar, posterior cerebral, superior cerebellar and posterior communicating arteries were observed from plastination slices, original images, MPR and MIP images. MRI revealed similar results to the plastination sections. The intracisternal segment of oculomotor nerve formed an angle with the posterior plane of the brainstem. The angle was significantly smaller in individuals under 10 and over 50 years old ( P<0.05), and there was no marked difference in the angle between the oculomotor nerve and the median sagittal plane among the different groups ( P>0.05). Shift of the basilar artery was more likely to be found in aged individuals. Most of the posterior cerebral and superior cerebellar arteries were close to the nerve, and a few of them seemed to compress it; for the posterior communicating artery, only the embryonic type was close to or seemed to compress the nerve. MRI is an accurate imaging technique for determination of the relationship of the oculomotor nerve to its related arteries.