Characteristics and Application of a Novel Cold-Adapted and Salt-Tolerant Protease EK4-1 Produced by an Arctic Bacterium Mesonia algae K4-1

Mesonia algae K4-1 from the Arctic secretes a novel cold-adapted and salt-tolerant protease EK4-1. It has the highest sequence similarity with Stearolysin, an M4 family protease from Geobacillus stearothermophilus, with only 45% sequence identity, and is a novel M4 family protease. Ek4-1 has a low optimal catalytic temperature (40 °C) and is stable at low temperatures. Moreover, EK4-1 is still active in 4 mol/L NaCl solution and is tolerant to surfactants, oxidizing agents and organic solvents; furthermore, it prefers the hydrolysis of peptide bonds at the P1' position as the hydrophobic residues, such as Leu, Phe and Val, and amino acids with a long side chain, such as Phe and Tyr. Mn²⁺and Mg²⁺ significantly promoted enzyme activity, while Fe³⁺, Co⁺, Zn²⁺ and Cu²⁺ significantly inhibited enzyme activity. Amino acid composition analysis showed that EK4-1 had more small-side-chain amino acids and fewer large-side-chain amino acids. Compared with a thermophilic protease Stearolysin, the cold-adapted protease EK4-1 contains more random coils (48.07%) and a larger active pocket (727.42 ų). In addition, the acidic amino acid content of protease EK4-1 was higher than that of the basic amino acid, which might be related to the salt tolerance of protease. Compared with the homologous proteases EB62 and E423, the cold-adapted protease EK4-1 was more efficient in the proteolysis of grass carp skin, salmon skin and casein at a low temperature, and produced a large number of antioxidant peptides, with DPPH, ·OH and ROO· scavenging activities. Therefore, cold-adapted and salt-tolerant protease EK4-1 offers wide application prospects in the cosmetic and detergent industries.

Novel Antioxidant Peptides Identified from Arthrospira platensis Hydrolysates Prepared by a Marine Bacterium Pseudoalteromonas sp. JS4-1 Extracellular Protease

Crude enzymes produced by a marine bacterium Pseudoalteromonas sp. JS4-1 were used to hydrolyze phycobiliprotein. Enzymatic productions showed good performance on DPPH radical and hydroxyl radical scavenging activities (45.14 ± 0.43% and 65.11 ± 2.64%, respectively), especially small peptides with MWCO <3 kDa. Small peptides were fractioned to four fractions using size-exclusion chromatography and the second fraction (F2) had the highest activity in hydroxyl radical scavenging ability (62.61 ± 5.80%). The fraction F1 and F2 both exhibited good antioxidant activities in oxidative stress models in HUVECs and HaCaT cells. Among them, F2 could upregulate the activities of SOD and GSH-Px and reduce the lipid peroxidation degree to scavenge the ROS to protect Caenorhabditis elegans under adversity. Then, 25 peptides total were identified from F2 by LC-MS/MS, and the peptide with the new sequence of INSSDVQGKY as the most significant component was synthetized and the ORAC assay and cellular ROS scavenging assay both illustrated its excellent antioxidant property.

The investigation of hepatitis A virus and hepatitis E virus co-infection in humans and animals in China

The aim of this study was to investigate the prevalence of co-infection of hepatitis A and hepatitis E virus (HAV/HEV) in patients with acute hepatitis as well as in different animal species. A total of 46 serum samples from patients diagnosed as hepatitis A or hepatitis E and 675 fecal samples of 11 animal species were collected. The IgM class antibodies to HEV and HAV, respectively, were detected by enzyme-linked immunosorbent assay. HEV and HAV RNAs were extracted from serum and fecal samples for the nested reverse transcription polymerase chain reaction. At least 10.9% (5/46) of the patients were co-infected with both HAV and HEV. Fifteen percent (18/120) of rabbit fecal samples and 17.5% (7/40) of swine fecal samples were positive for HEV RNA, but only 1% (2/200) of ferret fecal samples were positive for HAV RNA. Our study showed that co-infection with both HAV and HEV in patients and animals is infrequent. At least in our study, we showed that ferrets may represent the potential HAV hosts. Keywords: hepatitis A virus; hepatitis E virus; co-infection; zoonosis; prevalence.

0075 Neural Correlates of Cognitive Fatigue in Parkinson Disease

Introduction

Parkinson’s disease (PD) is a common neurodegenerative disease affecting millions of people world-wide. Fatigue is a prevalent and debilitating non-motor symptom in PD. However, the neural correlates underlying cognitive fatigue are poorly understood. Our previous studies suggested that continuous performance of a simple but mentally demanding psychomotor vigilance task (PVT) induced cognitive fatigue, operationalized as subjective exhaustion and time-on-task performance decline. Here we used arterial spin labeling (ASL) perfusion fMRI to investigate regional cerebral blood flow (CBF) changes in PD patients during cognitive fatigue induced by continuous performance of 20-min PVT.

Methods

Twenty-one PD patients completed a 20-min PVT during the ASL scan and two additional 4-min resting-state ASL scans before and after PVT. Reaction times (RTs) and regional CBF changes throughout the PVT as well as during pre- and post-task resting baselines were measured. Cognitive fatigue was analyzed by dividing the entire PVT performance into five quintiles in addition to the immediate measurement of self-rated fatigue before and after PVT.

Results

PD patients demonstrated significantly increased self-reported fatigue ratings after the task (p &lt; 0.05) and progressively slower RTs across quintiles (p &lt; 0.05). Perfusion data showed that the PVT activates the right middle frontal cortex, right inferior parietal lobe, right insula, bilateral occipital cortex, and right cerebellum (FDR corrected). Moreover, the bilateral middle frontal gyri were less active during the post-task rest compared to the pre-task rest.

Conclusion

These results demonstrated that cognitive fatigue has an ongoing effect on brain activity after a period of continuous mental effort and supported the critical role of prefrontal cortex in mediating cognitive fatigue in PD. The findings also suggest the utility of continuous PVT as an appropriate paradigm to induce and examine cognitive fatigue in PD.

Support

Supported in part by Parkinson’s Foundation Translational Research Grant and NIH grants R01-MH107571, R21-AG051981, and P30-NS045839.

1100 Self-Monitoring Of PVT Performance In Healthy Adults And Individuals With MDD

Introduction

Negativity bias in depression has been repeatedly demonstrated in the judgment and decision-making literature. Research investigating the impact of sleep deprivation on self-evaluation of performance in healthy or depressed populations is limited. We examined 1) whether individuals with Major Depressive Disorder (MDD) exhibit a negativity bias in subjective ratings of performance on the Psychomotor Vigilance Task (PVT) as compared with healthy adults, and 2) the impact of total sleep deprivation (TSD) on these ratings.

Methods

N=33 individuals with MDD and n=9 healthy adults completed a 5-day study protocol including two baseline nights (B1-B2, 9h TIB), 36 hours of TSD, and one night of recovery sleep opportunity (Rec). The PVT was administered every 2-4 hours. A brief questionnaire was administered immediately prior to (PRE) and following (POST) the PVT, asking participants to estimate their average reaction time (RT) using a 9-point Likert-type scale. Mixed-effects models examined the impact of group (MDD, Control), protocol day (B1, B2, SD, Rec), and their interaction on objective PVT performance (mean RT) and subjective performance estimates (PRE and POST ratings).

Results

Mean RT was significantly slower during TSD (p&lt;0.001) for all participants. Individuals with MDD and healthy adults did not differ in objective PVT performance (p=0.25) across days. There was no significant interaction between group and protocol day (p=0.96). Both groups predicted slower RTs during TSD as compared with baseline or recovery days (PRE-PVT, p=0.006). Individuals with MDD anticipated slower RTs as compared with healthy adults (p=0.001). On POST-PVT estimates, all participants reported subjective poorer performance during TSD (p&lt;0.008). Individuals with MDD reported slower RTs as compared with healthy adults (p=0.002). Interaction effects between group and protocol day on PRE- and POST- performance ratings were not significant.

Conclusion

This project is the first to investigate subjective estimates of PVT performance in healthy and depressed individuals. Individuals with MDD subjectively reported slower response times as compared with control participants, despite similar objective performance. Depressive symptoms may be a potential confounder of subjective, but not objective, PVT performance.

Support

5R01MH107571

0294 Baseline Response Speed Predicts Locus Coeruleus Integrity Change After Sleep Deprivation

Introduction

Locus coeruleus (LC) is the major source of norepinephrine (NE) in the brain, which plays a key role in maintaining arousal and alertness. Sleep loss significantly impairs arousal and alertness. However, it is unknown whether sleep loss disrupts LC integrity, which can be measured non-invasively by diffusion tensor imaging (DTI). In the current study, we used DTI to examine the effects of one night of acute total sleep deprivation (TSD) on fractional anisotropy (FA), an index reflecting fiber density, axonal diameter and myelination.

Methods

We analyzed DTI and psychomotor vigilance test (PVT) data from N=54 health adults (23 females, age range 21–50 years) from a well controlled in-laboratory sleep deprivation study. Participants were randomized to either a TSD condition (n=40) without sleep on night 2, or a control condition (n=14) with no sleep loss. Standard DTI scans were conducted on the morning of day 2 and day 3 between 0700h-1000h. The PVT reciprocal response time (RRT) was used to measure individual’s response speed at baseline without sleep loss. LC regions-of-interest (ROI) were defined by standard templates from Keren et al. (2009). Imaging data were analyzed using FSL toolbox.

Results

For the whole TSD group, no differences were found in the LC FA values before and after sleep deprivation (p &gt; .2). However, when dividing the TSD group to a slow group and a fast group based on their baseline PVT response speed, significantly increased LC FA were found in the slow group (p = .007) but not in the fast group (p &gt; .4). The PVT RRT negatively correlated with LC FA value changes after TSD (r = -.44, p = .004). No correlations were found between the PVT RRT and LC FA changes in the control group.

Conclusion

Our results showed that baseline vigilance response speed correlated with LC integrity change after sleep deprivation, with slower response exhibiting greater changes in LC integrity. These findings support the key role of LC-NE system in the regulation of alertness and arousal.

Support

Supported in part by NIH grants R01-HL102119, R01-MH107571, R21-AG051981. CTRC UL1RR024134, and P30-NS045839.

0060 Morning Locus Coeruleus Activation During the PVT Predicts Later-Day Sleepiness

Introduction

The locus coeruleus (LC) plays a key role in the regulation of arousal and autonomic function. Homeostatic sleep pressure refers to the drive for sleep that increases as a saturating exponential when we stay awake and decreases exponentially when we sleep. The current study used arterial spin labeling (ASL) functional magnetic resonance imaging (fMRI) to investigate the relationship between homeostatic sleep pressure (sleepiness) and LC activity during the psychomotor vigilance test (PVT).

Methods

We analyzed sleepiness and ASL imaging data from N=70 health adults (40 males, age range 21–50 years) who participated in a controlled in-laboratory sleep study. All participants were scanned at rest and during the PVT on the morning between 0700h-1000h after 9 hour time-in-bed (TIB) baseline sleep. LC regions-of-interest (ROI) were defined by standard templates from Keren et al. (2009). Sleepiness was assessed by the Karolinska Sleepiness Scale (KSS) every two hours from 10:30 am to 10:30 pm.

Results

Sleepiness scores gradually increased over wakefulness time and reached its peak in the evening at about 10:20pm. PVT-induced CBF changes did not correlate with sleepiness scores on the morning (p &gt; 0.05), but showed significant negative correlations with sleepiness scores on later day when sleep pressure became higher, especially during the night-time (r = -0.41, p &lt; 0.001). Specifically, LC CBF showed significant increases during the PVT scan as compared to the resting scan (p = 0.04) in individuals with less nigh-time sleepiness (KSS &lt; 4), but no differences (p &gt; 0.1) in individuals with greater nigh-time sleepiness (KSS ≥ 5). After controlling for age, gender, and total sleep time, PVT-induced regional CBF difference in the LC still negatively predicted sleepiness (β = -0.325, p = 0.005).

Conclusion

Our findings showed that individuals with greater LC CBF increases during the PVT were less sleepy during the night, supporting the key role of LC activity in promoting wakefulness and maintaining sleep homeostasis. PVT-induced LC activation may provide a non-invasive bio-marker of homeostatic sleep pressure in healthy adults.

Support

Supported in part by NIH grants R01-HL102119, R01-MH107571, R21-AG051981. CTRC UL1RR024134, and P30-NS045839.

Field enhancement in a doubly resonant optical parametric oscillator

Single-resonant and (signal/idler) double-resonant optical parametric oscillators differ fundamentally on the conversion efficiency back to the pump wave. The nonpresent idler in the single-resonant case allows for signal intracavity enhancement well beyond the pump power level. This paper answers the question, how the phase-matched back conversion in a doubly-resonant system can be overcome to reveal substantial power enhancement, and what parameters it depends on. In a degenerate double-resonant OPO (DROPO) pumped by a thin-disk oscillator, an enhancement up to a factor of four is shown experimentally. Support of a semianalytical theory is presented with exceptionally simple relations between enhancement and intracavity losses. Interestingly, our theory predicts no fundamental limit to the maximal field enhancement or conversion efficiency.

Vinylogous Blaise Reaction: Conceptually New Synthesis of Pyridin-2-ones

A conceptually new synthesis of pyridine rings by a [C4 + CN] assembly has been developed by applying a vinylogous version of the classic Blaise reaction. The zinc-mediated reaction of (het)aryl or alkyl nitriles with ethyl-4-bromocrotonate provided a variety of C(6)-substituted pyridin-2-ones in a single-step.

The higher prevalence of truncal obesity and diabetes in American than Chinese patients with chronic hepatitis C might contribute to more rapid progression to advanced liver disease

BACKGROUND

Chronic hepatitis C virus (HCV) infection is the leading cause of cirrhosis and hepatocellular carcinoma (HCC) in the United States (US) and an emerging cause in China.

AIM

To compare the clinical characteristics of hepatitis C patients in the US and China, and factors influencing disease stage.

METHODS

Prospective study of 2 cohorts of HCV patients recruited at 1 site in the US and 3 sites in China. Standardised questionnaire on risk factors and medical history were used and diagnosis of cirrhosis and HCC was based on pre-defined criteria.

RESULTS

One thousand nine hundred and fifty seven patients (1000 US and 957 China) were enrolled. US patients were more likely to be men (61.4% vs 48.5%), older (median age 57 vs 53 years), obese (38.4% vs 16.8%) and diabetic (21.8% vs 10.8%). A significantly higher per cent of US patients had cirrhosis (38.2% vs 16.0%) and HCC (14.1% vs 2.7%). Investigator estimated time at infection in US was 10 years earlier than in Chinese patients but US patients were more likely to have advanced disease even after stratifying for duration of infection. Study site in the US, older age, truncal obesity, diabetes and prior HCV treatment were significant predictors of advanced disease on multivariate analysis.

CONCLUSIONS

HCV patients in the US had more advanced liver disease than those in China. We speculate that underlying fatty liver disease may be a major contributor to this difference, and management of glycometabolic abnormalities should occur in parallel with anti-viral therapy to achieve optimal outcomes.

Nonpharmacological interventions aimed at modifying health and behavioural outcomes for adults with asthma: a critical review

Evidence suggests that living with asthma is linked with psychological and behavioural factors including self-management and treatment adherence, and therefore, there is a reasonable hypothesis that nonpharmacological treatments may improve health outcomes in people living with this condition. A systematic review of randomized controlled trials (RCTs) of nonpharmacological interventions for adults with asthma was designed. Databases searched included The Cochrane Airways Group Register of trials, CENTRAL and Psychinfo. The literature search was conducted until May 2014. Twenty-three studies met the inclusion criteria and were organized into four groups: relaxation-based therapies (n = 9); mindfulness (n = 1), biofeedback techniques (n = 3); cognitive behavioural therapies (CBT) (n = 5); and multicomponent interventions (n = 5). A variety of outcome measures were used, even when trials belonged to the same grouping, which limited the ability to conduct meaningful meta-analyses. Deficiencies in the current evidence base, notably trial heterogeneity, means that application to clinical practice is limited and clear guidelines regarding the use of nonpharmacological therapies in asthma is limited. Relaxation and CBT, however, appear to have a consistent positive effect on asthma-related quality of life and some psychological outcomes, and lung function (relaxation only). Future trials should be informed by previous work to harmonize the interventions under study and outcome measures used to determine their effectiveness; only then will meaningful meta-analyses inform clinical practice.

Oxidative stress-induced C/EBPβ inhibits β-catenin signaling molecule involving in the pathology of preeclampsia

INTRODUCTION

Oxidative stress-induced trophoblast cell dysfunction is a major pathology in preeclampsia (PE). Recently, CCAAT/enhancer binding protein beta (C/EBPβ) has been investigated as a tumor suppressor that participates in tumor invasion. However, the function of C/EBPβ in trophoblast cells remains unknown. Our study was designed to detect the expression of C/EBPβ in the preeclamptic placenta and to identify the underlying mechanisms of oxidative stress.

METHODS

Human placental tissues with PE were collected. The expression of C/EBPβ and β-catenin were detected. Human first trimester extravillous trophoblast cell (HTR8/SVneo) line exposed to hypoxia/reoxygenation (H/R) was employed as an oxidative stress model in vitro to investigate the effects of C/EBPβ on invasion and the expression of β-catenin. Moreover, first trimester-derived placental villous explants were used to verify the effects of C/EBPβ and β-catenin in placentation.

RESULTS

In preeclamptic placentas, C/EBPβ was overexpressed and β-catenin was decreased. In addition, C/EBPβ was found to have increased expression in H/R-treated HTR8/SVneo cells and villous explants. C/EBPβ knockdown and β-catenin activation could significantly promote the invasion of HTR8/SVneo cells, enhance the outgrowth and migration in villous explants and inhibit the excessive generation of intracellular ROS. These findings might be related to the increased activities of MMP-2/9 and the decreased expression of TIMP-1/2. Meanwhile, C/EBPβ knockdown remarkably increased the expression of β-catenin.

DISCUSSION

We hypothesize that the oxidative stress-induced overexpression of C/EBPβ might influence the activity of MMPs by regulating the Wnt/β-catenin signaling pathway to affect the invasion of trophoblast cells, which then participate in the pathogenesis of preeclampsia.

Zinc and Trimethylsilyl Chloride Mediated Synthesis of 2,3,5-Trisubstituted Pyrrole Diesters from Nitriles and Ethyl Bromoacetate

An efficient, zinc-mediated, single-pot and CN+3C type pseudo-four-component synthesis of 2,3,5-trisubstituted pyrrole diesters was achieved from readily available aromatic/benzylic/aliphatic nitriles and ethyl bromoacetate under trimethylsilyl chloride catalysis.

Genetic association study of GABRA2 single nucleotide polymorphisms and electroencephalography in alcohol dependence

The gamma aminobutyric acid (GABA) system has been implicated in the susceptibility to develop alcohol dependence and in determining electroencephalogram (EEG) beta activity. The role of the GABA receptor alpha-2 gene (GABRA2) in human alcohol dependence was determined in a genetic and electrophysiological study. The study population comprised 586 white UK individuals with alcohol dependence but a very low prevalence of co-morbid drug dependence, and 603 ancestrally matched healthy controls. Genotyping for seven GABRA2 single nucleotide polymorphisms (SNPs), identified from the literature as positively associated with alcohol dependence, was performed with success rates of 90% or greater. EEGs were available in 32 selected patients who had been abstinent from alcohol for a minimum of 24 months and in 138 ancestrally matched healthy controls. None of the SNPs showed allelic or haplotypic association with alcohol dependence. All markers were in Hardy Weinberg equilibrium (HWE) in the controls. HWE for marker rs279841 in the alcohol dependent sample was p=0.0199 and combined p=0.0166. Linkage disequilibrium patterns appear to be very similar to that observed in the HapMap CEU data. A significantly higher prevalence of excess EEG fast activity was found in the patients (31 vs. 14%, p=0.018). A significant relationship was found between the presence of excess EEG fast activity and GABRA2 SNPs rs548583, rs279871 and rs279841. This allelic association study provides no evidence for an association between GABRA2 polymorphisms and alcohol dependence. However, a significant relationship was identified between GABRA2 and excess EEG fast activity. This dissociation of effect may reflect the fact that the EEG is a more direct marker of phenotypic GABRA2 expression than the more heterogeneous alcohol dependence phenotype.

RNAi-mediated knockdown of AURKB and EGFR shows enhanced therapeutic efficacy in prostate tumor regression

Aurora B kinase (AURKB) and epidermal growth factor receptor 1 (EGFR) belong to serine/threonine and tyrosine kinase family of proteins. Both these kinases are found to overexpress in a large number of epithelial cancers, including hormonal refractory prostate cancer. In this communication, we present evidence for down-regulated expression of AURKB and EGFR, either alone or in combination, in prostate cancer cells. The results show that AURKB and EGFR were efficiently down-regulated in a dose-dependent manner. AURKB and EGFR siRNA in combination have shown enhanced therapeutic effect by inhibiting PC3 cell proliferation and inducing apoptosis in vitro, whereas androgen-dependent cancer cells LNCaP remain unaffected correlating the endogenous expression levels. Knockdown of AURKB and EGFR individually resulted in inhibition of prostate tumor growth in athymic nude mice and their combined knockdown resulted in tumor regression in which 40% of the treated mice were found to be tumor free, implicating the potential therapeutic benefits of AURKB-EGFR combination therapy.

A study of stigmatized attitudes towards people with mental health problems among health professionals

The project aimed to assess stigmatized attitudes among health professionals directed towards patients with mental health problems. The Attitude to Mental Illness Questionnaire was used to assess participants' attitudes towards fictitious patients from a secure forensic hospital and patients with schizophrenia and substance use disorders. Participants were health professionals from acute and mental health settings. In total, 108 completed questionnaires were received. Participants had highly stigmatized attitudes towards patients from a forensic hospital and those with active substance use disorders. Attitudes were less stigmatized to people with substance use disorders who were recovering in remission. This suggested that health professionals have stigmatized attitudes towards an illness such as schizophrenia and this is worse towards patients from a secure hospital. The manner in which patients with substance use disorder are presented can have a significant effect on stigmatized attitudes by health professionals.

Sleeping position, oxygenation and lung function in prematurely born infants studied post term

OBJECTIVE

To determine the effect of sleeping position on the lung function of prematurely born infants when post term, whether any effect was similar to that before discharge from the neonatal unit, and if it differed according to bronchopulmonary (BPD) status.

DESIGN

Prospective study.

SETTING

Tertiary neonatal unit.

PATIENTS

Twenty infants, median gestational age 30 weeks (range 25-32); 10 had BPD.

INTERVENTIONS

Before neonatal unit discharge (median age 36 weeks postmenstrual age (PMA)) and when post term, infants were studied prone and supine, each position maintained for 3 h.

MAIN OUTCOME MEASURES

Oxygen saturation was monitored continuously and, at the end of each 3 h period, functional residual capacity (FRC) and compliance (CRS) and resistance (RRS) of the respiratory system were measured.

RESULTS

At a median of 36 weeks PMA and 6 weeks later (post term), respectively, oxygen saturation (98% vs 96%, p = 0.001; 98% vs 97%, p = 0.011), FRC (26 vs 24 ml/kg, p<0.0001; 35 vs 31 ml/kg, p = 0.001) and CRS (3.0 vs 2.4 ml/cm H(2)O, p = 0.034; 3.7 vs 2.5 ml/cm H(2)O, p = 0.015) were higher in the prone than the supine position. In the prone position, both BPD and non-BPD infants had significantly greater FRCs on both occasions and oxygen saturation at 36 weeks PMA, but oxygen saturation was significantly better post term only in non-BPD infants. Twelve infants had superior oxygen saturation and 17 superior FRCs in the prone compared with the supine position at both 36 weeks PMA and post term.

CONCLUSIONS

These results suggest that lung function impairment does not explain why prematurely born infants are at increased risk of sudden infant death syndrome in the prone compared with the supine position.

Characteristics of patients who are violent to staff and towards other people from a community mental health service in South East England

Professionals working in the public sector in the UK report widespread violence towards staff working in areas such as health care, social services and education. This study compares the characteristics of patients with and without a history of violence in a large sample of patients attending a community mental health service in South East England. The data were taken from a study of comorbidity and cannabis use in a mental health trust covering a semi-rural population of 250,000 people in Harlow and the surrounding area of South East England. Key workers were interviewed using semi-structured questionnaires from the Comorbidity of Substance Misuse and Mental illness in Community Mental Health and Substance Misuse Services study. Rates of violence against health workers were more than 20 times higher among those patients with a history of violence (23.6% vs. 1%, P<0.001). Alcohol and drug use was more frequent in those who were violent. Prevalence of comorbidity, schizophrenia and personality disorders was high. Key workers' estimates suggested that there was no difference in aggression, engagement or adherence to care plan among those with a history of violence.

Predictive significance of bone sialoprotein and osteopontin for bone metastases in respectable non-small cell lung cancer: A retrospective study

7666

Background: Bone sialoprotein (BSP) and osteopontin (OPN) have been demonstrated predictive of bone metastases in breast and prostate carcinoma, consistent with the proposed role of BSP as a stimulator of bone mineralization and OPN in differentiation and activation of osteoclasts. Bone metastasis (BM) is often developed in non-small-cell lung cancer (NSCLC), but no predictive biomarker was identified for high risk of metastatic bone dissemination. Methods: 180 completely resected NSCLC patients were included in this study. 38 patients subsequently developed BM. Paraffin embedded primary tumor tissue of patients were supplied to produce a tissue microarray, and immunohistochemistry method was used for evaluation the expression of BSP and OPN. Different expressions of these two biomarkers among BM group and non-BM group were estimated by χ2 test. Bone metastasis-free survival was analyzed by Kaplan-Meier method. The prognostic impact of clinicopathologic parameters and biomarker expression was evaluated by Cox propotional hazards model. Results: BSP expression was associated with BM (P=0.027), while OPN expression could not reach statistical significance (P=0.495). Univariate analysis demonstrated that expression of BSP (P=0.036), N stage (P=0.000) and clinical stage (P=0.001) were associated with time interval to BM. Multivariate analyses showed BSP expression (RR=1.779, P=0.012) and clinical stage (RR=1.620, P=0.005) were independent prognostic factors for BM. Conclusions: BSP protein expression in the primary resected NSCLC is strongly associated with BM and could be used to identify high-risk patients. Correlation of OPN protein expression and bone metastasis need further investigation.

No significant financial relationships to disclose.

APOE epsilon4 and cognitive decline in older stroke patients with early cognitive impairment

BACKGROUND

Dementia is common post stroke, but the potential role of early cognitive impairment and APOE epsilon4 as risk factors is unclear.

METHOD

Stroke survivors older than 75 years without dementia at 3 months post stroke received a detailed neuropsychological evaluation at 3 and 15 months post stroke, which included the Cambridge Assessment of Mental Disorders in the Elderly (CAMCOG). Early cognitive impairment was diagnosed using the criteria for cognitive impairment/no dementia (vascular CIND). APOE genotype was determined using a standardized method.

RESULTS

One hundred thirty-seven older stroke patients without dementia (mean age 80.6 +/- 4.3, mean CAMCOG score 83.5 +/- 10.4, 68 women) participated in the study, of whom 40 met the criteria for CIND. Stroke patients with one or more APOE epsilon4 alleles were significantly more likely to have CIND (14/40 vs 17/97, odds ratio = 2.5, 95% CI 1.1 to 5.8). Over the 1 year of follow-up, CIND patients with one or more APOE epsilon4 alleles had a mean decline on the total CAMCOG of 2.7 points compared with an improvement of >4 points among patients without APOE epsilon4 (T = 2.9 p = 0.006). CIND patients with an APOE epsilon4 allele also experienced greater decline in memory (T = 2.5, p = 0.015).

CONCLUSION

In older stroke patients with early cognitive impairment, the presence of an APOE epsilon4 allele is associated with greater progression of cognitive decline. This has implications for interventions aimed at the secondary prevention of dementia in stroke patients.

Impact of hypertension and apolipoprotein E4 on poststroke cognition in subjects >75 years of age

BACKGROUND AND PURPOSE

The apolipoprotein E4 allele (APOE4) associates with increased dementia risk, and hypertension may associate with mild cognitive deficits. We examined whether nondemented stroke patients with (1) a prestroke history of hypertension and (2) APOE4 were more cognitively impaired at 3 months after stroke.

METHODS

A total of 257 participants were genotyped and outcomes from neuropsychological evaluations analyzed using regression.

RESULTS

Total Cambridge Assessment for Mental Disorders in the Elderly (CAMCOG) and speed of working memory significantly associated with hypertension. No outcomes significantly associated with APOE4.

CONCLUSIONS

Subjects with prestroke hypertension had more impaired global cognition and slower access to information held in working memory.

Continuum description of rarefied gas dynamics. I. Derivation from kinetic theory

We describe an asymptotic procedure for deriving continuum equations from the kinetic theory of a simple gas. As in the works of Hilbert, of Chapman, and of Enskog, we expand in the mean flight time of the constituent particles of the gas, but we do not adopt the Chapman-Enskog device of simplifying the formulas at each order by using results from previous orders. In this way, we are able to derive a new set of fluid dynamical equations from kinetic theory, as we illustrate here for the relaxation model for monatomic gases. We obtain a stress tensor that contains a dynamical pressure term (or bulk viscosity) that is process dependent and our heat current depends on the gradients of both temperature and density. On account of these features, the equations apply to a greater range of Knudsen number (the ratio of mean free path to macroscopic scale) than do the Navier-Stokes equations, as we see in the accompanying paper. In the limit of vanishing Knudsen number, our equations reduce to the usual Navier-Stokes equations with no bulk viscosity.

Continuum description of rarefied gas dynamics. II. The propagation of ultrasound

The equations of fluid dynamics developed in Paper I [X. Chen, H. Rao, and E. A. Spiegel, Phys. Rev. E 64, 46308 (2001)] are applied to the study of the propagation of ultrasound waves. There is good agreement between the predicted propagation speed and experimental results for a wide range of Knudsen numbers.

A novel fibronectin binding site required for fibronectin fibril growth during matrix assembly

Fibronectin (FN) assembly into a fibrillar extracellular matrix is a stepwise process requiring participation from multiple FN domains. Fibril formation is regulated in part by segments within the first seven type III repeats (III1-7). To define the specific function(s) of this region, recombinant FNs (recFNs) containing an overlapping set of deletions were tested for the ability to assemble into fibrils. Surprisingly, recFN lacking type III repeat III1 (FNDeltaIII1), which contains a cryptic FN binding site and has been suggested to be essential for fibril assembly, formed a matrix identical in all respects to a native FN matrix. Similarly, displacement of the cell binding domain in repeats III9-10 to a position close to the NH2-terminal assembly domain, as well as a large deletion spanning repeats III4-7, had no effect on assembly. In contrast, two deletions that included repeat III2, DeltaIII1-2 and DeltaIII2-5, caused significant reductions in fibril elongation, although binding of FN to the cell surface and initiation of assembly still proceeded. Using individual repeats in binding assays, we show that III2 but not III1 contains an FN binding site. Thus, these results pinpoint repeat III2 as an important module for FN-FN interactions during fibril growth.

Degradation of a cohesin subunit by the N-end rule pathway is essential for chromosome stability

Cohesion between sister chromatids is established during DNA replication and depends on a protein complex called cohesin. At the metaphase-anaphase transition in the yeast Saccharomyces cerevisiae, the ESP1-encoded protease separin cleaves SCC1, a subunit of cohesin with a relative molecular mass of 63,000 (Mr 63K). The resulting 33K carboxy-terminal fragment of SCC1 bears an amino-terminal arginine-a destabilizing residue in the N-end rule. Here we show that the SCC1 fragment is short-lived (t1/2 approximately 2 min), being degraded by the ubiquitin/proteasome-dependent N-end rule pathway. Overexpression of a long-lived derivative of the SCC1 fragment is lethal. In ubr1Delta cells, which lack the N-end rule pathway, we found a highly increased frequency of chromosome loss. The bulk of increased chromosome loss in ubr1Delta cells is caused by metabolic stabilization of the ESP1-produced SCC1 fragment. This fragment is the first physiological substrate of the N-end rule pathway that is targeted through its N-terminal residue. A number of yeast proteins bear putative cleavage sites for the ESP1 separin, suggesting other physiological substrates and functions of the N-end rule pathway.

Positive findings on bone scan in multiple myeloma

We report a case of multiple myeloma in which the bone lesions showed high uptake of technetium Tc 99m methylene diphosphonate on a bone scan. A review of the literature comparing the usefulness of conventional skeletal radiography and bone scans in diagnosing the osteolytic lesions of myeloma shows that bone scintigraphy, considered by many to have no role in the detection of osteolytic lesions of myeloma, is in fact more sensitive than radiography in detecting lesions in the ribs, scapula, and spine.

[Detection of Epstein-Barr virus, cell proliferation and apoptosis in thymic tumors]

OBJECTIVE

To investigate the incidence of thymic tumors in Guangzhou, its association with EBV infection and the cell proliferation and apoptosis characteristics of these tumors.

METHODS

EBV encoded small RNAs (EBERs) were detected in 43 thymic tumors and 7 thymic hyperplasia samples by use of in situ hybridization, EBNA-1, LMP-1, PCNA, bcl-2 and p53 were examined using immunohistochemical methods, cell apoptosis was evaluated by TUNEL (TdT-mediated dUTP-X nick end labelling) in situ cell death detection kit.

RESULTS

1. Thymic diseases only accounted for 0.057% of biopsies in the Guangzhou area. Thymic tumor and hyperplasia accounted for 74.7% and 18.6% in thymic diseases respectively. Thymic lymphoepithelimoa-like carcinoma (LELC) occurred in 2.7% of thymic tumors. 2. EBV encoded products (EBERs, EBNA-1 and LMP-1) were not detected in 50 thymic disease specimens. 3. Marked proliferation (3+-4+) grade thymomas (0/18 cases) was much lower than that of thymic carcinomas (10/20 cases), and the marked apoptotic (2+-4+) grade was higher in thymomas (15/18) than the thymic carcinomas (13/20). 4. The p53 protein accumulation rate in thymic carcinomas (8/20) was significantly higher than that of thymomas (1/18). The apoptotic grade is significantly related to p53 accumulation in thymic epithelial tumors. 5. The bcl-2 over expression could be detected both in thymomas and thymic carcinomas.

CONCLUSIONS

1. Thymic diseases, including thymic LELC, is very rare in Guangzhou and is not closely associated with EBV infection. 2. Thymic carcinomas have a relatively rapid growth rate compared to thymomas. 3. p53 gene mutation may play an important role in the carcinogenesis of thymic carcinoma, and bcl-2 over-expression may also be involved in the evolution of thymic epithelial tumors. 4. Wild type p53 protein may exert an apoptosis-inducing function in thymic epithelial tumors, including thymomas and carcinomas, and a proliferation inhibiting function only in thymomas.