A forwards induction approach to candidate drug selection

A forwards induction policy is a type of greedy algorithm for Markov decision processes. It is straightforward to implement and is optimal for a large class of models, especially in stochastic resource allocation. In this paper we consider a model for the optimal allocation of resources in pre-clinical pharmaceutical research. We show that although they are not always strictly optimal, forwards induction policies perform well.

Metabolic Characteristics in Obese Patients Complicated by Mild Thyroid Hormone Deficiency

The prevalence of subclinical hypothyroidism (SH) is increasing, especially in obese people. The purpose of this study was to evaluate the difference in metabolic profiles between obese patients with mild increased thyrotropin (TSH) or with normal TSH. A total of 219 obese patients were recruited in this cross-sectional study. They were divided into 2 groups: obese patients with normal TSH (0.35-2.5 mU/l) and age-, and body mass index (BMI)-matched obese patients with higher-normal TSH (2.5-5.5 mU/l). We have named it compensatory hypothyroidism or mild thyroid hormone deficiency. Anthropometric data, glucose-lipid metabolism, markers of inflammation, body composition, and thyroid function parameters were measured. Results showed that: 1) The levels of fasting plasma glucose (FPG), high density lipoprotein cholesterol (HDL-C), and 25-hydroxyvitamin D levels were significantly lower in obese patients complicated by mild increased TSH than in obese patients with normal TSH (p<0.05). The fasting insulin (FINS) and C reactive protein (CRP) levels were significantly higher in obese patients complicated by mild increased TSH when compared to the obese patients with normal TSH (p<0.01). Jostel's TSH index (TSHI) and standard TSH index (sTSHI) were significantly higher in obesity with mild increased TSH when compared to obesity with normal TSH (both p<0.001). Thyroid's secretory capacity (GT) was significantly lower in obesity with mild increased TSH when compared to obesity with normal TSH (p<0.001). 2) In the obese patients complicated by mild increased TSH group, serum TSH was significantly positively correlated with ALT, AST and CP (p<0.05). In the obese patients with normal TSH group, serum TSH was significantly positively correlated with UA (p<0.05). In all subjects, serum TSH was significantly positively correlated with ALT, AST, FINS, CP, CRP, and UA (p<0.05), but negatively with DBP, FPG, and HDL-C (p<0.05). 3) There was significant difference of the prevalence of hyperinsulinemia and impaired fasting glucose (IFG) between the 2 groups (p<0.05). In Conclusion, obesity complicated by mild increased TSH manifested higher fasting insulin levels, more severe chronic low-grade inflammation, and lower HDL-C levels than obesity with normal TSH.

A profile of sphingolipids and related compounds tentatively identified in yak milk

This work characterized a fraction of constituents in yak milk within the realm of approximately 1,000 to 3,000 Da using matrix-assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometry. Eleven samples of yak milk powder from the Sichuan province of China were received by the Department of Food Science, University of Wisconsin-Madison, and stored at room temperature until analysis. Sample preparation involved delipidation and deproteinization of yak milk samples and cold ethanol precipitation. Subsequently, MALDI time-of-flight mass spectrometry was performed in positive ion, reflector mode (AB Sciex TOF/TOF 4800 MALDI; AB Sciex, Foster City, CA). The instrument was first calibrated with the manufacturer's 6-peptide mixture, and each spectrum was internally calibrated using the accurate mass of ACTH Fragment 18-39 standard peptide (protonated mass at m/z 2464.199) present in each sample. Laser power was adjusted for the calibration standards and for each sample so that the signal obtained for the most-abundant ion in each spectrum could be maximized, or kept below ~2×10(4) to preserve spectral quality. Structure and name based on mass were matched using the Metlin metabolite database (https://metlin.scripps.edu/index.php). Results of the current work for yak milk powder showed a large variety of sphingolipid structures with clusters around 1,200, 1,600, and 2,000 Da. The profiling matched several glycosphingolipids, such as gangliosides GA1, GD1a, GD1b, GD3, GM1, GM2, GM3, and GT2 and several other unique moieties, including deaminated neuraminic acid (KDN) oligosaccharides, and fucose containing gangliosides. Matrix preparation and MALDI time-of-flight parameters were important factors established in this work to allow high resolution profiling of complex sphingolipids in yak powder milk.

Novel highly conductive ferroferric oxide/porous carbon nanofiber composites prepared by electrospinning as anode materials for high performance Li-ion batteries

Ferroferric oxide/porous carbon nanofiber composites were synthesized by electrospinning and subsequent innovative thermal treatments, exhibiting enhanced electrochemical performance.

Serum Irisin Level is Higher and Related with Insulin in Acanthosis Nigricans-related Obesity

OBJECTIVE

Acanthosis nigricans (AN) is proved to be a skin phenotype of hyperinsulinemia especially in obese patients. Irisin is a new myokine which plays an important role in metabolic disorders, such as obesity, insulin resistance, and type 2 diabetes. The role of irisin in the development of AN-related obesity is not yet understood. In this study, we aimed to investigate the relationship between irisin and AN-related obesity. Patients & Measurements: 30 obese patients without AN (OB group), 30 obese patients with AN (AN group), and 20 age-matched healthy volunteers (control group, CON) were included in this study. Weight, BMI, lipid profile, FFA, UA, and CRP were measured in all participants. Oral Glucose Tolerance tests (OGTT) were performed and serum glucose and plasma insulin were measured at 0, 30, 60,120 and 180 min. The AUC (area under curve) of glucose and insulin was calculated. Serum irisin was measured by ELISA.

RESULTS

Hyperinsulinemia is found in both AN and OB groups. The AN group had higher levels of insulin but better blood glucose tolerance and insulin response. The difference in irisin levels between the 3 groups was statistically significant, with the AN group showing the highest serum level of irisin. Serum irisin levels were positively correlated with BMI, and fasting insulin.

CONCLUSION

AN is a state of hyperinsulinmia and has better insulin response and glucose tolerance compared to obese patients without AN. Serum irisin may be a protective factor against impaired beta cell function in obesity with AN.

A novel mutation of the androgen receptor gene in familial complete androgen insensitivity syndrome

OBJECTIVE

Androgen insensitivity syndrome (AIS) is characterized by androgen receptor (AR) dysfunction. Its main characteristic is a female phenotype in an individual with a 46, XY karyotype. The molecular basis of this disorder was investigated in two individuals with familial AIS.

PATIENTS AND METHODS

The diagnoses of the two individuals were confirmed using ultrasonography, hormonal analysis, operative findings, and a histopathological study. Blood samples were collected, and the AR genes were analyzed using PCR and direct sequencing.

RESULTS

Clinical and laboratory testing confirmed the two individuals' diagnoses of CAIS. DNA sequencing analysis of the genomes of these patients revealed a novel mutation of c.2107T > C in exon 4 of the AR gene, which results in a transformation of the protein p.S703P. The individuals' mother possesses a heterozygous allele, implying that she is a heterozygous carrier of the mutant gene.

CONCLUSIONS

These findings suggested that this previously undescribed novel mutation of the AR gene is the cause of CAIS in this family.

Treatment of patients with diabetic peripheral neuropathic pain in China: a double-blind randomised trial of duloxetine vs. placebo

BACKGROUND

Duloxetine has been approved in the United States, European Union and some Asian countries for the treatment of diabetic peripheral neuropathic pain (DPNP). We assessed the efficacy and safety of duloxetine (60 mg once daily) compared with placebo in Chinese patients suffering from DPNP.

METHODS

This was a phase 3, multicenter, randomised, double-blind, parallel, placebo-controlled, 12-week trial of the treatment of DPNP with duloxetine. Subjects were male and female outpatients ≥ 18 years of age with DPNP, as assessed by the Michigan Neuropathy Screening Instrument, and had a rating of ≥ 4 on the Brief Pain Inventory-Modified Short Form-Severity weekly average pain item. The primary efficacy measure was the reduction in pain severity from baseline to 12 weeks, as measured by the weekly mean of 24-h average pain ratings recorded in the patient's diary. Mean changes from baseline in efficacy measures were analysed by a restricted maximum likelihood-based, mixed-effects model repeated measures approach and by analysis of covariance.

RESULTS

Of the 405 patients randomised, 203 patients were assigned to duloxetine 60 mg once daily and 202 patients were assigned to placebo. Duloxetine-treated patients showed significantly greater pain relief on 24-h average pain ratings compared with placebo-treated patients each week of the 12-week study period [week 12: least squares (LS) mean change duloxetine: -2.40, placebo: -1.97; LS mean change difference (95% confidence interval) = -0.43 (-0.82, -0.04), p = 0.030]. Compared with placebo, patients treated with duloxetine experienced higher rates of nausea (p = 0.010), somnolence (p < 0.001) and asthenia (p = 0.002).

CONCLUSIONS

Duloxetine-treated patients showed significantly greater pain relief compared with placebo-treated patients over the 12-week study period. Duloxetine was shown in Chinese patients to have a safety profile similar to that found in previous duloxetine trials.

Overexpression of superoxide dismutase 3 gene blocks high-fat diet-induced obesity, fatty liver and insulin resistance

Oxidative stress plays an important role in the development of obesity and obesity-associated metabolic disorders. As an endogenous antioxidant enzyme, superoxide dismutase 3 (SOD3) has the potential to affect diet-induced obesity and obesity associated complications. In the current work, we overexpressed SOD3 in C57BL/6 mice fed a high fat diet to study its effect on high fat diet-induced obesity, fatty liver and insulin resistance. We demonstrated that the Sod3 gene transfer blocked high fat diet induced obesity, fatty liver and insulin resistance. Real Time PCR analysis of adipose and liver tissues revealed that overexpression of the Sod3 gene suppressed expression of pro-inflammatory genes in adipose tissue including F4/80, Tnfα, Cd11c, Mcp1 and Il6, and increased expression of anti-inflammatory genes such as adiponectin. In the liver, high levels of SOD3 activity in animals enhanced expression of the genes responsible for energy expenditure including Cpt1α, Cpt1β, Pgc1α, Pgc1β and Ucp2. These results suggest that overexpression of the Sod3 gene through gene transfer is an effective approach in preventing diet induced obesity and obesity-associated complications.

Concurrent chemoradiotherapy followed by adjuvant chemotherapy compared with concurrent chemoradiotherapy alone for the treatment of locally advanced nasopharyngeal carcinoma: a retrospective controlled study

OBJECTIVE

We evaluated the survival benefit of providing concurrent chemoradiotherapy (ccrt) plus adjuvant chemotherapy compared with ccrt alone to patients with locally advanced nasopharyngeal carcinoma.

METHODS

This retrospective study included 130 patients with nasopharyngeal carcinoma treated with ccrt plus adjuvant chemotherapy from June 2005 to December 2010. Another 130 patients treated with ccrt alone during the same period were matched on age, sex, World Health Organization histology, T stage, N stage, and technology used for radiotherapy. The endpoints included overall survival, locoregional failure-free survival, distant metastasis failure-free survival, and failure-free survival.

RESULTS

At a mean follow-up of 42.1 months (range: 8-85 months), the observed hazard ratios for the group receiving ccrt plus adjuvant chemotherapy compared with the group receiving ccrt alone were: for overall survival, 0.77 [95% confidence interval (ci): 0.37 to 1.57]; for locoregional failure-free survival, 1.00 (95% ci: 0.37 to 2.71); for distant metastasis failure-free survival, 1.15 (95% ci: 0.56 to 2.37); and for failure-free survival, 1.26 (95% ci: 0.69 to 2.28). There were no significant differences in survival between the groups. After stratification by disease stage, ccrt plus adjuvant chemotherapy provided a borderline significant benefit for patients with N2-3 disease (hazard ratio: 0.35; 95% ci: 0.11 to 1.06; p = 0.052). Multivariate analyses indicated that only tumour stage was a prognostic factor for overall survival.

CONCLUSIONS

Patients with locally advanced nasopharyngeal carcinoma received no significant survival benefit from the addition of adjuvant chemotherapy to ccrt. However, patients with N2-3 disease might benefit from the addition of adjuvant chemotherapy to ccrt.

Neonatal mortality rate and risk factors in northeast China: analysis of 5,277 neonates in 2005

BACKGROUND

Healthcare has dramatically improved for both mothers and neonates over the last three decades in China. However, the reported rates of morbidity and mortality vary among different regions of China, and the exact rates in Northeast China are unknown. This study aimed to determine neonatal morbidity and mortality rates and the associated risk factors in Northeast China.

MATERIALS AND METHODS

Neonates born in 2005 at seven hospitals in five major cities of Heilongjiang province in Northeast China were recruited. Standardized questionnaires on both the mother and neonate were conducted by trained investigators. The questions included demographic data on the mother, the mother's weight, gestational age (GA), complications during pregnancy, method of delivery, neonate's gender, weight, general health situation, and complications after delivery. Results: A total of 5,277 neonates were included, with a male to female ratio of 1.07. The incidence ofpreterm delivery was 8.7%, which was associated with an increased age of the mother, a history of preeclampsia-eclampsia, premature rupture of membranes, and intrauterine distress. Morbidity occurred in 7.0% of neonates, including hypoxic ischemic encephalopathy (2.4%), asphyxia (1.6%), pneumonia (1.6%), hyperbilirubinemia (0.5%), intracranial hemorrhage (0.5%), meconium as- piration syndrome (0.2%), and ingestion syndrome (0.2%). The overall mortality was 9.5%0. Preterm delivery, maternal history ofpreeclamp- sia-eclampsia, hypoxic ischemic encephalopathy, intracranial hemorrhage, pneumonia, asphyxia, and meconium aspiration syndrome were independent risk factors for mortality with odds ratios (95% confidence interval) of 17.42 (7.31-38.9), 12.52 (Table 3) (3.91-16.82), 10.13 (2.52-19.86), 9.77 (2.35-19.93), 4.15 (1.78-9.52), 2.18 (1.21-5.47), and 2.76 (2.11-6.32), respectively (all P<0.01).

CONCLUSIONS

In 2005, the overall morbidity and mortality was 7.0% and 9.5%0, respectively in northeast China, and preterm delivery was the highest risk factor for neonatal mortality. The prevention on preterm delivery should be a top priority for the improvement of neonatal healthcare.

Hyperthyroidism caused by acquired immune deficiency syndrome

BACKGROUND

Acquired immune deficiency syndrome (AIDS) is an immune deficiency disease. The etiology of hyperthyroidism, which can also be immune-related, is usually divided into six classical categories, including hypophyseal, hypothalamic, thyroid, neoplastic, autoimmune and inflammatory hyperthyroidism. Hyperthyroidism is a rare complication of highly active antimicrobial therapy (HAART) for human immunodeficiency virus (HIV). Hyperthyroidism caused directly by AIDS has not been previously reported.

PATIENT FINDINGS

A 29-year-old man who complained of dyspnea and asthenia for 1 month, recurrent fever for more than 20 days, and breathlessness for 1 week was admitted to our hospital. The thyroid function test showed that the level of free thyroxine (FT4) was higher than normal and that the level of thyroid-stimulating hormone (TSH) was below normal. He was diagnosed with hyperthyroidism. Additional investigations revealed a low serum albumin level and chest infection, along with diffuse lung fibrosis. Within 1 month, he experienced significant weight loss, no hand tremors, intolerance of heat, and perspiration proneness. We recommended an HIV examination; subsequently, AIDS was diagnosed based on the laboratory parameters.

SUMMARY

This is the first reported case of hyperthyroidism caused by AIDS.

CONCLUSIONS

AIDS may cause hyperthyroidism by immunization regulation with complex, atypical, and easily ignored symptoms. Although hyperthyroidism is rare in patients with AIDS, clinicians should be aware of this potential interaction and should carefully monitor thyroid function in HIV-positive patients.

Osteocalcin, glucose metabolism, lipid profile and chronic low-grade inflammation in middle-aged and elderly Chinese

AIM

To assess the relationship between serum total osteocalcin and measurements of adiposity, glucose tolerance, lipid profile, adipokine and chronic low-grade inflammation in middle-aged and elderly Chinese subjects.

METHODS

We performed a cross-sectional community-based study in central Shanghai. Serum total osteocalcin was measured by radioimmunoassay in 783 men and 946 post-menopausal women. Their associations with measurements of adiposity, glucose tolerance, lipid profile and chronic low-grade inflammation were examined.

RESULTS

Serum total osteocalcin levels revealed a sexual dimorphism, with post-menopausal women having significantly higher levels than men (P < 0.001). Serum osteocalcin levels of participants with self-reported cardiovascular disease were significantly lower (P = 0.044) than those without. In men, serum osteocalcin levels of participants with the metabolic syndrome were significantly lower than those without the metabolic syndrome (P = 0.036). Serum osteocalcin correlated negatively with fasting serum insulin, homeostasis model assessment of insulin resistance, alanine aminotransferase, triglycerides and total cholesterol, and positively with homeostasis model assessment of β-cell function in both men and post-menopausal women (all P < 0.05). In men, serum osteocalcin correlated negatively with BMI, diastolic blood pressure, fasting plasma glucose and 2-h oral glucose tolerance test glucose after adjustment for age (all P < 0.05). In post-menopausal women, serum osteocalcin correlated negatively with waist-hip ratio, LDL cholesterol and C-reactive protein, and positively with adiponectin (all P < 0.05). Serum osteocalcin was not associated with CXC chemokine ligand 5 level (P > 0.05). Alanine aminotransferase was an independent predictor of serum osteocalcin in both men and post-menopausal women (both P < 0.001). Adiponectin was an independent predictor of serum osteocalcin in post-menopausal women (P = 0.011). Serum osteocalcin was an independent predictor of homeostasis model assessment of β-cell function in both genders (both P < 0.05).

CONCLUSIONS

Serum total osteocalcin was closely associated with glucose and lipid metabolism in both Chinese men and post-menopausal women.

PP2A inactivation is a crucial step in triggering apoptin-induced tumor-selective cell killing

Apoptin (apoptosis-inducing protein) harbors tumor-selective characteristics making it a potential safe and effective anticancer agent. Apoptin becomes phosphorylated and induces apoptosis in a large panel of human tumor but not normal cells. Here, we used an in vitro oncogenic transformation assay to explore minimal cellular factors required for the activation of apoptin. Flag-apoptin was introduced into normal fibroblasts together with the transforming SV40 large T antigen (SV40 LT) and SV40 small t antigen (SV40 ST) antigens. We found that nuclear expression of SV40 ST in normal cells was sufficient to induce phosphorylation of apoptin. Mutational analysis showed that mutations disrupting the binding of ST to protein phosphatase 2A (PP2A) counteracted this effect. Knockdown of the ST-interacting PP2A-B56γ subunit in normal fibroblasts mimicked the effect of nuclear ST expression, resulting in induction of apoptin phosphorylation. The same effect was observed upon downregulation of the PP2A-B56δ subunit, which is targeted by protein kinase A (PKA). Apoptin interacts with the PKA-associating protein BCA3/AKIP1, and inhibition of PKA in tumor cells by treatment with H89 increased the phosphorylation of apoptin, whereas the PKA activator cAMP partially reduced it. We infer that inactivation of PP2A, in particular, of the B56γ and B56δ subunits is a crucial step in triggering apoptin-induced tumor-selective cell death.

Metabolic effects of bariatric surgery in type 2 diabetic patients with body mass index < 35 kg/m2

AIM

The aim of this meta-analysis is to assess the metabolic effects of bariatric surgery in type 2 diabetes mellitus (T2DM) patients with body mass index (BMI) < 35 kg/m(2) .

METHODS

We performed an electronic literature search of published articles to identify relevant evidence since inception to June 2011. Primary outcome measures were metabolic improvement and resolution diabetes after bariatric surgery. The weighted mean difference (WMD) and its 95% confidence interval (CI) were calculated from the raw data extracted from the original literature. The software Review Manager (version 4.3.1) was applied for meta-analysis.

RESULTS

Thirteen trials involving 357 patients were included in the meta-analysis. The follow-up interval ranged from 6 months to 18 years. According to WMD calculation, bariatric surgery led to 5.18 kg/m(2) of BMI lowering (95% CI, 3.79-6.57, p < 0.00001), 4.8 mmol/l of fasting plasma glucose (FPG) decrement (95% CI, 3.88-5.71 mmol/l, p < 0.00001), 2.59% of HbA1c decreasing (95% CI, 2.12-3.07%, p < 0.00001), 56.67 mg/dl of triglyceride decrement (95% CI 11.53-101.82, p = 0.01) and 48.38 mg/dl of total cholesterol reduction (95% CI 21.08-75.68, p = 0.0005). Moreover, the procedures produced an increased high-density lipoprotein cholesterol by 5.37 mg/dl (95% CI -11.37-0.63, p = 0.08). However, this effect was not statistically significant. Overall, 80.0% of the patients achieved adequate glycaemic control (HbA1c < 7%) without antidiabetic medication. The surgeries produced a low incidence of major complications (3.2%) with no mortality.

CONCLUSIONS

Bariatric surgery is effectual and safe in the treatment of non-severely obese (BMI < 35 kg/m(2) ) T2DM patients. Moreover, the metabolic benefits acquired from the procedures can be long sustained after the surgery.

Metabolic effects of bariatric surgery in type 2 diabetic patients with body mass index < 35 kg/m2

AIM

The aim of this meta-analysis is to assess the metabolic effects of bariatric surgery in type 2 diabetes mellitus (T2DM) patients with body mass index (BMI) < 35 kg/m(2) .

METHODS

We performed an electronic literature search of published articles to identify relevant evidence since inception to June 2011. Primary outcome measures were metabolic improvement and resolution diabetes after bariatric surgery. The weighted mean difference (WMD) and its 95% confidence interval (CI) were calculated from the raw data extracted from the original literature. The software Review Manager (version 4.3.1) was applied for meta-analysis.

RESULTS

Thirteen trials involving 357 patients were included in the meta-analysis. The follow-up interval ranged from 6 months to 18 years. According to WMD calculation, bariatric surgery led to 5.18 kg/m(2) of BMI lowering (95% CI, 3.79-6.57, p < 0.00001), 4.8 mmol/l of fasting plasma glucose (FPG) decrement (95% CI, 3.88-5.71 mmol/l, p < 0.00001), 2.59% of HbA1c decreasing (95% CI, 2.12-3.07%, p < 0.00001), 56.67 mg/dl of triglyceride decrement (95% CI 11.53-101.82, p = 0.01) and 48.38 mg/dl of total cholesterol reduction (95% CI 21.08-75.68, p = 0.0005). Moreover, the procedures produced an increased high-density lipoprotein cholesterol by 5.37 mg/dl (95% CI -11.37-0.63, p = 0.08). However, this effect was not statistically significant. Overall, 80.0% of the patients achieved adequate glycaemic control (HbA1c < 7%) without antidiabetic medication. The surgeries produced a low incidence of major complications (3.2%) with no mortality.

CONCLUSIONS

Bariatric surgery is effectual and safe in the treatment of non-severely obese (BMI < 35 kg/m(2) ) T2DM patients. Moreover, the metabolic benefits acquired from the procedures can be long sustained after the surgery.

Reduction of ordering temperature of self-assembled FePt nanoparticles by addition of Au and Ag

The [FePt]94Au6 and [FePt]90Ag10 nanoparticle arrays were synthesized on Si substrates by a reverse micellar method, combined with plasma treatment and in-situ deposition of a SiO2 overlayer, and the post annealing step was performed to drive the face-centered cubic to tetragonal phase transition. These FePt nanoparticles exhibit a quasi-hexagonal order with tailored inter-particle spacing and particle size. The effects of the Ag and Au on the structural and magnetic properties of FePt were investigated. The results indicate that both Au and Ag additives can remarkably enhance the coercivity and reduce the ordering temperature, however, the optimum composition is different for them. The optimum composition is determined to be [FePt]94Au6 and [FePt]90Ag10, respectively, for which the ordering temperature of FePt nanoparticles is reduced by -100 degrees C. After 600 degrees C annealing, the [FePt]94Au6 and [FePt]90Ag10 nanoparticles are totally ferromagnetic with apparent larger coercivities of -7.0 kOe, which is about 3.8 kOe larger than that of the pure FePt nanoparticles. The mechanism of the chemical ordering acceleration may be attributed to the defects and strains caused by the Au/Ag additives.

Context-based Word Acquisition for Situated Dialogue in a Virtual World

To tackle the vocabulary problem in conversational systems, previous work has applied unsupervised learning approaches on co-occurring speech and eye gaze during interaction to automatically acquire new words. Although these approaches have shown promise, several issues related to human language behavior and human-machine conversation have not been addressed. First, psycholinguistic studies have shown certain temporal regularities between human eye movement and language production. While these regularities can potentially guide the acquisition process, they have not been incorporated in the previous unsupervised approaches. Second, conversational systems generally have an existing knowledge base about the domain and vocabulary. While the existing knowledge can potentially help bootstrap and constrain the acquired new words, it has not been incorporated in the previous models. Third, eye gaze could serve different functions in human-machine conversation. Some gaze streams may not be closely coupled with speech stream, and thus are potentially detrimental to word acquisition. Automated recognition of closely-coupled speech-gaze streams based on conversation context is important. To address these issues, we developed new approaches that incorporate user language behavior, domain knowledge, and conversation context in word acquisition. We evaluated these approaches in the context of situated dialogue in a virtual world. Our experimental results have shown that incorporating the above three types of contextual information significantly improves word acquisition performance.

Magnetic Properties of FePt Nanoparticles Prepared by a Micellar Method

FePt nanoparticles with average size of 9 nm were synthesized using a diblock polymer micellar method combined with plasma treatment. To prevent from oxidation under ambient conditions, immediately after plasma treatment, the FePt nanoparticle arrays were in situ transferred into the film-growth chamber where they were covered by an SiO2 overlayer. A nearly complete transformation of L10 FePt was achieved for samples annealed at temperatures above 700 °C. The well control on the FePt stoichiometry and avoidance from surface oxidation largely enhanced the coercivity, and a value as high as 10 kOe was obtained in this study. An evaluation of magnetic interactions was made using the so-called isothermal remanence (IRM) and dc-demagnetization (DCD) remanence curves and Kelly-Henkel plots (ΔM measurement). The ΔM measurement reveals that the resultant FePt nanoparticles exhibit a rather weak interparticle dipolar coupling, and the absence of interparticle exchange interaction suggests no significant particle agglomeration occurred during the post-annealing. Additionally, a slight parallel magnetic anisotropy was also observed. The results indicate the micellar method has a high potential in preparing FePt nanoparticle arrays used for ultrahigh density recording media.

Predictors for casual sex and/or infection among sexually transmitted disease clinic attendees in China

To assess the risk factors for casual sex and infections among the sexually transmitted disease (STD) clinic attendees in two disparate Chinese cities, an STD clinic-based cross-sectional study was conducted to provide demographic and sexual behaviour information. Participants were recruited from nine STD clinics selected by mapping strategy. STD prevalence was 69.4% (68.6% of men and 65.2% of women). The most common diagnoses were non-gonococcal urethritis (22.2%), genital warts (13.2%), syphilis (11.6%), gonorrhoea (8.4%), chlamydia (6.3%) and herpes simplex virus type 2 (HSV-2) (5.8%). Of 536 participants, 22.5% reported having casual sex in the last three months, younger age, less education, unawareness of transmission routes and having had casual sex in the last three months were independent risk factors for acquisition of an STD. Single or separated marital status, non-local residency and STD diagnoses were independently associated with having had casual sex. After decades of exceedingly low STD rates in China, a full panoply of STD diagnoses are now evident. Both for reproductive health concerns and for stemming the expansion of HIV spread, STD control and prevention must be revitalized as a priority for China's public health and medical institutions. Effective training is a priority, given the dearth of STD-experienced health-care workers.

Clinical outcomes of basilar artery aneurysms

To evaluate the effects of endovascular treatments, we retrospectively analyzed a consecutive series of patients with basilar artery aneurysms (BAAs) treated endovascularly. During a seven year period, 43 patients (mean age 42.2 years, male/female ratio 21:22) with BAAs were treated mainly with endovascular techniques at Beijing Tiantan Hospital. Pretreatment clinical grades were determined using the Hunt-Hess scale. Outcome was evaluated using the Glasgow Outcome Scale scores (GOS) during a mean follow-up period of 21.1 months (range, 1 to 72 months). Forty-three patients had 44 BAAs, one MCA aneurysm and one P1 aneurysm. Endovascular treatment was technically feasible in 40 patients. One aneurysm thrombosed spontaneously after initial angiography. Four (9.3%) patients died periprocedurally. Immediate postprocedural angiograms in 44 BAAs showed that complete occlusion was achieved in 33 BAAs, subtotal occlusion in one and incomplete occlusion in seven. Follow-up angiographic results in 30 patients confirmed complete occlusion of 27 aneurysms, subtotal occlusion in one, and incomplete occlusion in two. Two patients with vertebrobasilar atheromatous fusiform aneurysms were treated with antiplatelet medications. Long-term outcome was good (GOS Score 4 or 5) in 39 patients (90.7%) and fatal (GOS Score 1) in four (9.3%). Favorable overall long-term outcome can be achieved in patients with BA apex aneurysms, and in 78.6% of those with BA trunk aneurysms when using endovascular techniques. Endovascular coil embolization of BAAs is an effective treatment in the long-term. Patients with vertebrobasilar atheromatous fusiform aneurysms can be treated with antiplatelet medications.

Composition deviation of arrays of FePt nanoparticles starting from poly(styrene)-poly(4-vinylpyridine) micelles

Ordered arrays of FePt nanoparticles were prepared using a diblock polymer micellar method combined with plasma treatment. Rutherford backscattering spectroscopy analyses reveal that the molar ratios of Fe to Pt in metal-salt-loaded micelles deviate from those when metal precursors are added, and that the plasma treatment processes have little influence upon the compositions of the resulting FePt nanoparticles. The results from Fourier transform infrared spectroscopy show that the maximum loadings of FeCl(3) and H(2)PtCl(6) inside poly(styrene)-poly(4-vinylpyridine) micelles are different. The composition deviation of FePt nanoparticles is attributed to the fact that one FeCl(3) molecule coordinates with a single 4-vinylpyridine (4VP) unit, while two neighboring and uncomplexed 4VP units are required for one H(2)PtCl(6) molecule. Additionally, we demonstrate that the center-to-center distances of the neighboring FePt nanoparticles can also be tuned by varying the drawing velocity.

Rate dependence of crack-tip processes predicts twinning trends in f.c.c. metals

Crack-tip behaviour in metals is among the most basic problems in mechanics of materials. Yet, long-standing experimental evidence suggests that crack-tip twinning in face-centred-cubic (f.c.c.) metals is highly dependent on the material, temperature and loading rate, and previous simulations and models predict twinning in aluminium, where it has never been observed. Here, this discrepancy between theory and experiment is resolved through a new model guided and validated by extensive multiscale simulations. Both the analytic model and simulations reveal a transition from crack-tip twinning at short times to full dislocation formation at long times. Applied to a host of f.c.c. metals, the model agrees with experimental trends as it predicts large differences in the thermal activation needed for full dislocation emission to dominate. More broadly, this work demonstrates the necessity of multiscale modelling and attention to rate dependence for accurate description of material behaviour and computationally guided material design.

Cognitive Principles in Robust Multimodal Interpretation

Multimodal conversational interfaces provide a natural means for users to communicate with computer systems through multiple modalities such as speech and gesture. To build effective multimodal interfaces, automated interpretation of user multimodal inputs is important. Inspired by the previous investigation on cognitive status in multimodal human machine interaction, we have developed a greedy algorithm for interpreting user referring expressions (i.e., multimodal reference resolution). This algorithm incorporates the cognitive principles of Conversational Implicature and Givenness Hierarchy and applies constraints from various sources (e.g., temporal, semantic, and contextual) to resolve references. Our empirical results have shown the advantage of this algorithm in efficiently resolving a variety of user references. Because of its simplicity and generality, this approach has the potential to improve the robustness of multimodal input interpretation.

Inhibition of hepatocarcinoma by systemic delivery of Apoptin gene via the hepatic asialoglycoprotein receptor

Specificity is a prerequisite for systemic gene therapy of hepatocarcinoma. In vitro, the tumor-specific viral death effector Apoptin selectively induces apoptosis in malignant hepatic cells. Intratumoral treatment of xenografted subcutaneous hepatomas with Apoptin results in tumor regression. Here, we report a systemic delivery vehicle containing the Apoptin gene linked to asialoglycoprotein (Asor), which targets asialoglycoprotein receptor (ASGPR) present only on the surface of hepatocytes. In vitro, the protein-DNA complex Asor-Apoptin induced apoptosis in HepG2 hepatocarcinoma cells but not in normal L-02 hepatocytes. Non-hepatocyte-derived tumorigenic human A549 cells lacking the membrane ASGPR were not affected by Asor-Apoptin. In vivo systemic delivery of Asor-Apoptin via the tail vein into mice bearing in situ hepatocarcinoma resulted in specific and efficient distribution of Apoptin in both hepatocarcinoma cells and normal hepatocytes. Five days after injection of Asor-Apoptin, the in situ hepatocarcinomas showed significant signs of regression, whereas the surrounding normal hepatocytes did not. Systemically delivered Asor-LacZ expressing non-apoptotic LacZ gene did not inhibit tumor growth. Our data reveal that systemic delivery of Asor-Apoptin specifically induces apoptosis in malignant hepatocytes and thus constitutes a powerful and safe therapeutics against hepatocarcinomas.

Functional polymorphisms in cell death pathway genes FAS and FASL contribute to risk of lung cancer

BACKGROUND

The FAS and FASL system plays a key role in regulating apoptotic cell death and corruption of this signalling pathway has been shown to participate in immune escape and tumorigenesis. There is reduced expression of FAS but elevated expression of FASL in many types of human cancers including lung cancer. We recently reported an association between functional polymorphisms in FAS (-1377G-->A) and FASL (-844T-->C) and risk of oesophageal cancer.

OBJECTIVE

To examine the contribution of these polymorphisms to risk of developing lung cancer.

METHODS

Genotypes of 1000 lung cancer patients and 1270 controls were analysed by PCR based restriction fragment length polymorphism. Associations with risk of lung cancer were estimated by logistic regression.

RESULTS

Compared with non-carriers, there was a 1.6 fold excess risk of developing lung cancer for carriers of the FAS -1377AA genotype (odds ratio (OR) 1.59, 95% confidence interval (CI) 1.21 to 2.10; p = 0.001), and 1.8 fold excess risk (OR 1.79, 95% CI 1.26 to 2.52; p = 0.001) for carriers of FASL -844CC. Gene-gene interaction of FAS and FASL polymorphisms increased risk of lung cancer in a multiplicative manner (OR for the carriers of both FAS -1377AA and FASL -844CC genotypes 4.18, 95% CI 2.83 to 6.18). Gene-environment interaction of FAS or FASL polymorphism and smoking associated with increased risk of lung cancer was also found.

CONCLUSION

These results are consistent with our initial findings in oesophageal cancer and further support the hypothesis that the FAS and FASL triggered apoptosis pathway plays an important role in human carcinogenesis.

Studies on the growth metabolism of Bacillus thuringiensis and its vegetative insecticidal protein engineered strains by microcalorimetry

The metabolic power-times curves of Bacillus thuringiensis and its vegetative insecticidal protein engineered strains were determined at 30 degrees C by using a thermal activity monitor air Isothermal Microcalorimeter, ampoule method. From the power-times curves, the maximum power (Pmax) in the log phase, the growth rate constant (k), the generation times (tG), the time of the maximum power (tmax), the heat effects (Qlog) for log phase, and the total heat effect in 45 h (Qtotal) of B. thuringiensis strains can be obtained. The results indicate that their power-times curves are different. The relationship between their metabolic power-times curves and character of bacteria metabolism, and thermokinetics and gene expression were analyzed and discussed. The character of the bacteria power-times curves reflected the physiologic character of gene expression. The microcalorimetric method proved to be a reliable and sensitive tool for the assessment of the growth metabolism, the heat output in bacteria and its engineered strains. The determination of the thermokinetic character is beneficial to the control of fermentation.

Inhibition of Angiogenesis Is Associated With Reduced Islet Engraftment in Diabetic Recipient Mice

Rapid reestablishment of a functional microvasculature in transplanted islets is crucial for islet survival and function. To illustrate the importance of angiogenesis in islet engraftment, we took a loss-of-function approach to block angiogenesis in newly transplanted islets and determined the extent of islet engraftment in correlation with islet mass and glycemic control in diabetic recipient mice. Diabetic mice were transplanted with a marginal mass of 200 islets under the renal capsule, followed by once-daily oral administration of saline or 150 mg/kg of C-statin, a potent angiogenic inhibitor, for 14 days. Blood glucose profiles and the amplitude of glucose-stimulated insulin secretion in engrafted islets were determined. At 30 days posttransplant, islet grafts were retrieved for the determination of insulin content and vascular density by immunohistochemistry. When compared to sham-treated controls, diabetic recipient mice receiving a daily oral dose of C-statin exhibited significantly impaired blood glucose profiles and diminished glucose-stimulated insulin secretion in response to glucose challenge, correlating with significantly reduced intragraft insulin content and vascular density. Selective inhibition of angiogenesis was associated with reduced islet mass in diabetic mice. These data extend our view that rapid onset of angiogenesis is crucial for islet survival and engraftment and support the development of therapeutic strategies to stimulate angiogenesis in newly implanted islets for enhancing islet engraftment and improving the outcome of marginal islet transplantation.

Projections of diencephalic dopamine neurons into the spinal cord in mice

The aim of this study is to investigate the pathway of diencephalic dopaminergic (DA) neuronal innervating into the spinal cord in mice, the pathway is postulated relevant to clinical restless legs syndrome (RLS). Tyrosine hydroxylase (TH) immunohistochemistry was used to identify the DA neuron. The fluorescent tracer Fluoro-Gold (FG) was stereotaxically injected into the T10-L5 spinal cord of CBL57 mice (n=20) seven days before the animals were sacrificed. The diencephalic sections were stained with TH antibody and the FG tracer present in the diencephalic DA neurons were examined under fluoresce microscope. The average number of total DA neurons per side in A11, A12, A13 and A14 was 66+/-8, 221+/-12, 350+/-17 and 254+/-21 respectively. After being injected into the spinal cord, FG reached the DA neurons within the A10 and A11 groups, but didn't target to any other DA neuron groups including the A8 and A9 groups in substantia nigra (SN). The diencephalic A11 DA neurons possessed long axons extending over several segments and possibly traversing the entire length of the spinal cord. It is the first time to report A10 and A11 DA neuron projections into the spinal cord in mice.

Experimental study on the antitumor effect of mouse B7-1 gene

Mouse B7-1 cDNA was cloned by RT-PCR from BALB/C mouse splenic cells and inserted into pcDNA3 to construct an eukaryotic expression vector. This constructor was named pCD-mB7-1, in which the B7-1 cDNA was identified to be consistent with the data from other researchers. pCD-mB7-1 plasmid was transfected into B16(F0) cells, and effective expression of mB7-1 in these tumor cells could be detected till the 6th month by RT-PCR and RNA hybridization. Specific cytotoxity assay of lymphocytes was conducted after culturing with tumor cells and the results demonstrated that B16 cells transfected with B7-1 gene were more effective than B16-wt and B16-neo in inducing specific cytotoxity of lymphocytes against B16-wt cells. It is suggested that expression of B7-1 gene in tumor cells could enhance the immunogenicity and induce the effective antitumor immunity.

The recent expansion of Pluto's atmosphere

Stellar occultations--the passing of a relatively nearby body in front of a background star--can be used to probe the atmosphere of the closer body with a spatial resolution of a few kilometres (ref. 1). Such observations can yield the scale height, temperature profile, and other information about the structure of the occulting atmosphere. Occultation data acquired for Pluto's atmosphere in 1988 revealed a nearly isothermal atmosphere above a radius of approximately 1,215 km. Below this level, the data could be interpreted as indicating either an extinction layer or the onset of a large thermal gradient, calling into question the fundamental structure of this atmosphere. Another question is to what extent Pluto's atmosphere might be collapsing as it recedes from the Sun (passing perihelion in 1989 in its 248-year orbital period), owing to the extreme sensitivity of the equilibrium surface pressure to the surface temperature. Here we report observations at a variety of visible and infrared wavelengths of an occultation of a star by Pluto in August 2002. These data reveal evidence for extinction in Pluto's atmosphere and show that it has indeed changed, having expanded rather than collapsed, since 1988.