Cardiopulmonary Protection for Bilateral Breast Irradiation: A Dosimetric Comparison between Proton and Photon Plans

PURPOSE/OBJECTIVE(S)

Recent advances in cancer treatment improve cancer survivorship. Cardiovascular disease has become the leading cause of non-cancer death in breast cancer survivors. Therefore, risk of cardiopulmonary toxicities during multimodality treatment should be assessed carefully. It remains to be defined the best scenario for proton therapy to confer meaningful cardiovascular protection in the setting of breast irradiation. We hypothesized proton therapy plan provides optimal cardiopulmonary protection during bilateral breast irradiation. The study aimed to compare cardiopulmonary dosimetric parameters of proton and photon radiotherapy plans.

MATERIALS/METHODS

We conducted a retrospective study and patients with bilateral breast cancer indicated for radiotherapy between January 01, 2010 and December 31, 2020 were included. All patients received whole breast or chest wall irradiation with or without regional nodal irradiation. The dose scheme was 50-50.4 Gy in 25-28 fractions. Boost was allowed if patients receiving breast conserving surgery or known risk factors. The dosimetric parameters included planning target volume, mean dose to the heart, the volume of whole lung receiving 5 Gy, 10 Gy, and 20 Gy. For photon therapy, volumetric modulated arc therapy using double partial arc plans was generated with Pinnacle 9.8, Elekta Synergy and tomotherapy helical plan was generated with Tomo Hi-Art planning system. For proton therapy, treatment planning was generated with Ray station 9A. All data was managed using SAS v.9.4 software. Analysis of variance (α = 0.05) was used to compute the dosimetry of different treatment modalities. The statistical significance was considered with a p-value <0.05.

RESULTS

Thirty-one patients with bilateral breast cancer were included, including 12 bilateral breast irradiation patients and 6 bilateral chest wall irradiation patients. The mean dose of heart was 53.0±43.3 cGy in proton therapy while 736.6±225.1 cGy and 869.67±241.0 cGy in Tomotherapy and volumetric modulated arc therapy respectively. The volume of whole lung receiving 5 Gy was 15.4±7.91% in proton therapy while 46.1±10.8% and 46.3±2.5% in Tomotherapy and volumetric modulated arc therapy respectively. The volume of whole lung receiving 20 Gy was 7.7±4.3% in proton therapy while 15.4±5.6% and 19±3.5% in Tomotherapy and volumetric modulated arc therapy respectively. The effects of cardiopulmonary protection were more significant for chest wall irradiation over breast irradiation.

CONCLUSION

Proton radiotherapy provided significant dose reduction for bilateral breast irradiation. The benefit is more significant is patients receiving bilateral chest wall irradiation. Further clinical validations will be warranted to confirm the clinical relevance of the finding.

Safety Profile of Combination Treatment with Radiotherapy and Immune Checkpoint Blockades: A Multi-Institute Real World Experience

PURPOSE/OBJECTIVE(S)

Immune checkpoint blockades have become widely used in recent years and have been approved as standard first-line and subsequent treatment for different types of malignancy. Combination treatment with irradiation also showed promising results in previous clinical studies. However, the treatment toxicities of this combination strategy have not been well defined. We hypothesized combination therapy does not add additional toxicities to immune checkpoint blockade alone. The study aims to investigate the safety profile of combination treatment with immune checkpoint blockade and radiotherapy in all type cancer patients.

MATERIALS/METHODS

We conducted a population-based retrospective cohort study using the electronic medical records from three hospitals in Taiwan from January 01, 2015, to December 31, 2020. Baseline demographic data, laboratory examination, and treatment history were collected. Patients with radiotherapy exposure and immune checkpoint blockade were enrolled. The primary endpoint was all grade toxicities. All patients were monitored from the date of initiating immune checkpoint blockade or irradiation until the event of death, loss follow-up, or any defined adverse events. All data was managed using SAS v.9.4 software. Kaplan-Meier estimators and cox proportional hazard regression models were used to compute the safety profile of combination treatment. The statistical significance was considered with a p-value <0.05.

RESULTS

A total of 305 cases, including 181 male patients and 124 female patients, received combination treatment with immune checkpoint blockade and radiotherapy with different time sequences. The most common cancer types are lung cancer (33.1%) followed by gastroesophageal cancer (16.7%) and hepatobiliary cancer (13.8%). The most common toxicities were arthralgia (25.9%), followed by enterocolitis (23.6%), and anemia (21%). 11 cases (3.6%) developed pneumonitis, 5 cases (1.6%) developed myocarditis, and 5 cases (1.6%) developed hepatitis during combination treatment.

CONCLUSION

There is no evidence leads to additional toxicities based on current real-world experience. Severe immune related adverse events were not increased with this combination strategy compared to historical data. This warrant further prospective analysis.

[To compare the efficacy and incidence of severe hematological adverse events of flumatinib and imatinib in patients newly diagnosed with chronic phase chronic myeloid leukemia]

Objective: To analyze and compare therapy responses, outcomes, and incidence of severe hematologic adverse events of flumatinib and imatinib in patients newly diagnosed with chronic phase chronic myeloid leukemia (CML) . Methods: Data of patients with chronic phase CML diagnosed between January 2006 and November 2022 from 76 centers, aged ≥18 years, and received initial flumatinib or imatinib therapy within 6 months after diagnosis in China were retrospectively interrogated. Propensity score matching (PSM) analysis was performed to reduce the bias of the initial TKI selection, and the therapy responses and outcomes of patients receiving initial flumatinib or imatinib therapy were compared. Results: A total of 4 833 adult patients with CML receiving initial imatinib (n=4 380) or flumatinib (n=453) therapy were included in the study. In the imatinib cohort, the median follow-up time was 54 [interquartile range (IQR), 31-85] months, and the 7-year cumulative incidences of CCyR, MMR, MR(4), and MR(4.5) were 95.2%, 88.4%, 78.3%, and 63.0%, respectively. The 7-year FFS, PFS, and OS rates were 71.8%, 93.0%, and 96.9%, respectively. With the median follow-up of 18 (IQR, 13-25) months in the flumatinib cohort, the 2-year cumulative incidences of CCyR, MMR, MR(4), and MR(4.5) were 95.4%, 86.5%, 58.4%, and 46.6%, respectively. The 2-year FFS, PFS, and OS rates were 80.1%, 95.0%, and 99.5%, respectively. The PSM analysis indicated that patients receiving initial flumatinib therapy had significantly higher cumulative incidences of CCyR, MMR, MR(4), and MR(4.5) and higher probabilities of FFS than those receiving the initial imatinib therapy (all P<0.001), whereas the PFS (P=0.230) and OS (P=0.268) were comparable between the two cohorts. The incidence of severe hematologic adverse events (grade≥Ⅲ) was comparable in the two cohorts. Conclusion: Patients receiving initial flumatinib therapy had higher cumulative incidences of therapy responses and higher probability of FFS than those receiving initial imatinib therapy, whereas the incidence of severe hematologic adverse events was comparable between the two cohorts.

A92 FEMALE AUTHORSHIP IN GASTROENTEROLOGY RANDOMIZED CONTROL TRIALS: 2011 - 2021

Background

Although tremendous strides have been made in the participation of women in medicine, female continues to be underrepresented in leadership positions and higher-level academic medicine. An important factor in determining career advancement in academic medicine is the quality and quantity of an individual’s scholarly publications. To date, no study has looked at female authorship in gastroenterology (GI) randomized control trials (RCTs), which remains the gold standard for evaluating intervention effectiveness.

Purpose

The primary outcome is to assess female authorship in gastroenterology randomized control trials from 2011 to 2021, and the secondary outcome is to assess female authorship within GI subspecialty RCT publications.

Method

In this observational study, the gender of the first and last author of gastroenterology RCTs from January 1, 2011 to December 31, 2021 was assessed. Python (v3.8.12) was used to extract publication data from PubMed. A validated algorithm, genderize.io, was used to determine gender. Author first names that cannot be determined by the algorithm were manually searched on publicly-available profiles.

Result(s)

A total of 5690 original gastroenterology RCTs were included from January 1, 2011 to December 31, 2021. The gender of the first and senior authors of the papers was determined for 5668 (99.6%) first authors and 5656 (99.4%) senior authors. Overall, 1937 (34.1%) of the first authors and 1138 (20.0%) of senior authors were female.

There was an increase in the proportion of female first authors over the past decade, from 25.4% in 2011 to 37.8% in 2021 (p<0.05). For senior authors, there was a more gradual increase in female authorship from 14.2% in 2011 to 21.6% in 2021 (p<0.05). (Figure 1)

Within GI subspecialties, 612 RCTs were included for inflammatory bowel disease, 1143 RCTs were included for hepatology, and 1856 RCTs were included for therapeutic endoscopy from January 1, 2011 to December 31, 2021. Further analysis will be performed to determine the gender trend for GI subspecialties.

Image

Conclusion(s)

Female authorship in gastroenterology RCTs has increased from 2011 to 2021, although the rate of senior authorship has increased to a slower extent compared to first authors. Across all years, female authorship in gastroenterology RCTs has been lower than males.

Please acknowledge all funding agencies by checking the applicable boxes below

None

Disclosure of Interest

None Declared

A127 TIMING OF CHOLECYSTECTOMY AFTER ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY IN A TERTIARY CENTRE: EVALUATION OF OUTCOMES

Background

Endoscopic retrograde cholangiopancreatography (ERCP) is the treatment of choice for patients with choledocholithiasis. Early cholecystectomy (within 24 to 72 hours) is recommended after the initial ERCP to reduce the risk of subsequent biliary events.

Purpose

To investigate the timing of cholecystectomy after ERCP in patients with choledocholithiasis and its associated outcomes in a single tertiary care centre.

Method

This is a retrospective analysis of adult patients who underwent cholecystectomy after ERCP from August 2021 to April 2022 at the University of Alberta Hospital. Outcomes data were stratified according to the length of time between ERCP and cholecystectomy, within 72 hours (early) or after 72 hours (delayed).

Result(s)

During the study period, 55 subjects were examined. Indications for ERCP included gallstone pancreatitis (24/55, 44%), choledocholithiasis (19/55, 34%), and acute cholangitis (12/55, 21%).

In total, 30 (55%) subjects received cholecystectomy within 72 hours, while 25 (45%) subjects received cholecystectomy after 72 hours. The two groups were comparable in age, sex ratios, and comorbidities. Out of the patients who received cholecystectomy after 72 hours, 8 (32%) subjects received their cholecystectomy on a subsequent admission. Of these, 2 subjects developed recurrent biliary events before their cholecystectomy, and 1 subject required a conversion to open cholecystectomy. There were no recurrent biliary events amongst the individuals with early cholecystectomy.

Subjects who received early cholecystectomy had a shorter total hospital stay compared to those with delayed cholecystectomy (4.5 days vs 7.3 days, p=0.0002). There was no significant difference between early and late cholecystectomy in conversion rate (3% vs 8%, p=0.58), average operating time (86min vs 83min, p=0.79), intraoperative complications including adhesions (13% vs 12%, p>0.05) and empyema (27% vs 28%, p>0.05), as well as histological rate of chronic cholecystitis (88% vs 92%, p=0.68).

Reasons associated with significantly delayed (>7 days) cholecystectomy after ERCP (n=12) include requiring coordination/consultation with other services prior to operation (3 subjects), prolonged course of gallstone pancreatitis (3 subjects), poor candidate for operation due to comorbidities (2 subjects), surgical cancellation/delays (2 subjects), post-ERCP pancreatitis (1 subject), and patient preference (1 subject).

Image

Conclusion(s)

Early cholecystectomy is associated with a shorter length of hospital stay and absence of recurrent biliary events. Other post-cholecystectomy outcomes were comparable. Early laparoscopic cholecystectomy should continue to be encouraged through an interdisciplinary approach.

Please acknowledge all funding agencies by checking the applicable boxes below

None

Disclosure of Interest

None Declared

Exercise priming with transcranial direct current stimulation: a study protocol for a randomized, parallel-design, sham-controlled trial in mild cognitive impairment and Alzheimer's disease

Background

Transcranial direct current stimulation (tDCS) is a non-invasive type of brain stimulation that uses electrical currents to modulate neuronal activity. A small number of studies have investigated the effects of tDCS on cognition in patients with Mild Cognitive Impairment (MCI) and Alzheimer’s disease (AD), and have demonstrated variable effects. Emerging evidence suggests that tDCS is most effective when applied to active brain circuits. Aerobic exercise is known to increase cortical excitability and improve brain network connectivity. Exercise may therefore be an effective, yet previously unexplored primer for tDCS to improve cognition in MCI and mild AD.

Methods

Participants with MCI or AD will be randomized to receive 10 sessions over 2 weeks of either exercise primed tDCS, exercise primed sham tDCS, or tDCS alone in a blinded, parallel-design trial. Those randomized to an exercise intervention will receive individualized 30-min aerobic exercise prescriptions to achieve a moderate-intensity dosage, equivalent to the ventilatory anaerobic threshold determined by cardiopulmonary assessment, to sufficiently increase cortical excitability. The tDCS protocol consists of 20 min sessions at 2 mA, 5 times per week for 2 weeks applied through 35 cm² bitemporal electrodes. Our primary aim is to assess the efficacy of exercise primed tDCS for improving global cognition using the Montreal Cognitive Assessment (MoCA). Our secondary aims are to evaluate the efficacy of exercise primed tDCS for improving specific cognitive domains using various cognitive tests (n-back, Word Recall and Word Recognition Tasks from the Alzheimer’s Disease Assessment Scale-Cognitive subscale) and neuropsychiatric symptoms (Neuropsychiatric Inventory). We will also explore whether exercise primed tDCS is associated with an increase in markers of neurogenesis, oxidative stress and angiogenesis, and if changes in these markers are correlated with cognitive improvement.

Discussion

We describe a novel clinical trial to investigate the effects of exercise priming before tDCS in patients with MCI or mild AD. This proof-of-concept study may identify a previously unexplored, non-invasive, non-pharmacological combination intervention that improves cognitive symptoms in patients. Findings from this study may also identify potential mechanistic actions of tDCS in MCI and mild AD.

Trial registration

Clinicaltrials.gov, NCT03670615. Registered on September 13, 2018.

Efficacy of non-invasive brain stimulation on global cognition and neuropsychiatric symptoms in Alzheimer's disease and mild cognitive impairment: A meta-analysis and systematic review

BACKGROUND

Non-invasive brain stimulation (NIBS) techniques have shown some promise in improving cognitive and neuropsychiatric symptoms (NPS) in people with Alzheimer's disease (AD) and its prodromal stage, mild cognitive impairment (MCI). However, data from clinical trials involving NIBS have shown inconsistent results. This meta-analysis investigated the efficacy of NIBS, specifically repetitive transcranial magnetic stimulation (rTMS), and transcranial direct current stimulation (tDCS) compared to sham stimulation on global cognition and NPS in people with AD and MCI.

METHOD

Multi-session randomized sham-controlled clinical trials were identified through MEDLINE, PsycINFO, and Embase until June 2021. Standardized mean difference (SMD) and 95% confidence interval (CI) between the active and sham treatments were calculated using random-effects meta-analyses. Included studies reported outcome measures for global cognition and/or NPS. Heterogeneity, from different NIBS techniques, disease populations, or tests used to assess global cognition or NPS, was measured using chi-square and I², and investigated using subgroup analyses. Possible effects of covariates were also investigated using meta-regressions.

RESULT

The pooled meta-analyses included 19 studies measuring global cognition (N_active=288, N_sham=264), and 9 studies investigating NPS (N_active=165, N_sham=140). NIBS significantly improved global cognition (SMD=1.14; 95% CI=0.49,1.78; p = 0.001; I² = 90.2%) and NPS (SMD=0.82; 95% CI=0.13, 1.50; p = 0.019; I² = 86.1%) relative to sham stimulation in patients with AD and MCI. Subgroup analyses found these effects were restricted to rTMS but not tDCS, and to patients with AD but not MCI. Meta-regression showed that age was significantly associated with global cognition response (N_studies=16, p = 0.020, I² = 89.51%, R² = 28.96%), with larger effects sizes in younger populations. All significant meta-analyses had large effect sizes (SMD ≥0.8), suggesting clinical utility of NIBS in the short term. There remained substantial heterogeneity across all subgroup analyses and meta-regressions (all I² > 50%). Egger's tests showed no evidence of publication biases.

CONCLUSION

rTMS improved global cognition and NPS in those with AD. Further studies in MCI and using tDCS will help to fully evaluate the specific NIBS techniques and populations most likely to benefit on global cognition and NPS measures. Additional research should investigate the long term clinical utility of NIBS in these populations.

Pharmacotherapy decisions among postmenopausal women attending a group medical consultation or a one-on-one specialist consultation at an osteoporosis center: an observational cohort study

Group medical visits for osteoporosis can improve access to care while being highly accepted by patients. In this study, a similar proportion of women planned to initiate pharmacotherapy after attending a group or traditional one-on-one osteoporosis consultation, indicating that the group consultation model does not produce unexpected treatment decisions.

INTRODUCTION

Group medical consultations for osteoporosis are time-efficient and highly accepted by patients, but effects on treatment decisions are unknown. We aimed to compare women's decisions to initiate or decline osteoporosis pharmacotherapy after attending either a group or transitional one-on-one osteoporosis consultation.

METHODS

In this observational study, we prospectively evaluated postmenopausal women referred to an osteoporosis clinic who attended a group medical visit and compared their decisions regarding pharmacologic osteoporosis treatment with retrospective data from a cohort of women who attended a traditional consultation. Both consultation types involved interaction with a specialist physician, individualized fracture risk estimation (using FRAX®), and education regarding fracture consequences and available osteoporosis medications. Both forms of consultation emphasized shared decision-making; however, group consultation attendees did not receive personalized treatment recommendations from the physician.

RESULTS

We reviewed the records of 125 women (median age 63 years) who attended a group consultation and 83 women (median age 64 years) who attended a traditional consultation between 2016 and 2019. Twenty-four (19%) of the group cohort and 16 (19%) of the traditional cohort were at high 10-year risk of major osteoporotic fracture (FRAX® ≥ 20.0%). A similar proportion planned to initiate pharmacologic therapy after the group and traditional consultations (23% vs 16%, p = 0.22); these proportions were comparable among women at high risk (42% vs 50%, p = 0.75) and moderate risk (19% vs 15%, p = 0.77), but a higher proportion of low-risk women planned to initiate therapy after the group consultation (18% vs 0%, p = 0.009).

CONCLUSION

Patient decisions to initiate pharmacologic treatment made during a group visit are similar to those made during traditional one-on-one consultation. The group consultation model represents an alternative to one-on-one assessment for delivering osteoporosis consultative services.

The association between placebo arm inclusion and adverse event rates in antidepressant randomized controlled trials: An examination of the Nocebo Effect

BACKGROUND

Antidepressant efficacy is influenced by patient expectations and, in randomized controlled trials (RCTs), the probability of receiving a placebo. It is unclear whether tolerability demonstrates a similar pattern. This study aimed to determine whether study design influences adverse event (AE) rates in antidepressant trials for subjects receiving active treatment or placebo.

METHODS

RCTs comparing one antidepressant to another antidepressant, placebo, or both in major depressive disorder (MDD) (1996-2018) were retrieved from Medline and PsycINFO. Clinicaltrials.gov was searched for unpublished trials. Of 1,997 studies screened, 77 trials were included. Studies were classified as drug-drug, drug-drug-placebo, or drug-placebo based on design and overall number of subjects experiencing any AE was recorded. Subgroup meta-analysis of proportions and meta-regression techniques were used to compare AE rates across study designs in patients receiving active antidepressant treatment and placebo.

RESULTS

Among the actively treated, AE rates were lower in drug-drug trials (58.5%) compared to drug-drug-placebo (75.7%) and drug-placebo (76.4%) (the model reported coefficients for percent differences between AE rates of different study designs were B=17.0, p<0.001 and B=17.8, p<0.001, respectively). AE rates in patients receiving placebo were not different between study designs.

LIMITATIONS

The present study is limited by the diverse range of study populations, variability in reporting of AEs, and specific antidepressants employed in the included trials.

CONCLUSIONS

The inclusion of a placebo arm in the study design was unexpectedly associated with higher rates of AEs among patients receiving active medication in antidepressant trials. This observation has important implications for interpretation of trial tolerability findings.

Evidence-based umbrella review of 162 peripheral biomarkers for major mental disorders

The literature on non-genetic peripheral biomarkers for major mental disorders is broad, with conflicting results. An umbrella review of meta-analyses of non-genetic peripheral biomarkers for Alzheimer's disease, autism spectrum disorder, bipolar disorder (BD), major depressive disorder, and schizophrenia, including first-episode psychosis. We included meta-analyses that compared alterations in peripheral biomarkers between participants with mental disorders to controls (i.e., between-group meta-analyses) and that assessed biomarkers after treatment (i.e., within-group meta-analyses). Evidence for association was hierarchically graded using a priori defined criteria against several biases. The Assessment of Multiple Systematic Reviews (AMSTAR) instrument was used to investigate study quality. 1161 references were screened. 110 met inclusion criteria, relating to 359 meta-analytic estimates and 733,316 measurements, on 162 different biomarkers. Only two estimates met a priori defined criteria for convincing evidence (elevated awakening cortisol levels in euthymic BD participants relative to controls and decreased pyridoxal levels in participants with schizophrenia relative to controls). Of 42 estimates which met criteria for highly suggestive evidence only five biomarker aberrations occurred in more than one disorder. Only 15 meta-analyses had a power >0.8 to detect a small effect size, and most (81.9%) meta-analyses had high heterogeneity. Although some associations met criteria for either convincing or highly suggestive evidence, overall the vast literature of peripheral biomarkers for major mental disorders is affected by bias and is underpowered. No convincing evidence supported the existence of a trans-diagnostic biomarker. Adequately powered and methodologically sound future large collaborative studies are warranted.

Antidepressant-placebo differences for specific adverse events in major depressive disorder: A systematic review

BACKGROUND

Adverse events (AEs) are known to occur while patients are treated with placebos, part of the so-called nocebo effect. Yet evidence is limited regarding the likelihood that specific AEs occurring with antidepressant treatment are or are not due to nocebo effects.

METHODS

This study identified 56 placebo-controlled, randomized controlled trials (RCTs) of antidepressant monotherapy for adults with major depressive disorder that reported AE rates in sufficient detail for comparison. Poisson regression analyses compared rates of AEs according to antidepressant class weighted by study population to determine which separated from placebo. A "nocebo index" was also calculated (with 0 defined as the lowest rate and 1 or higher indicating the same or greater rate of an AE in the placebo group).

RESULTS

Numerous AEs did not differ statistically between antidepressant classes and placebo including worsening psychiatric symptoms, all forms of pain, weight gain and respiratory symptoms. Nevertheless, a number of AEs were significantly more common in antidepressants than placebos across multiple antidepressant classes. These were predominantly neurological, sexual and anticholinergic effects. Several AEs that separated statistically between antidepressants and placebos nevertheless had moderate nocebo indices (≥0.5). For example, dizziness in SSRIs separated significantly from placebo (OR 1.50, 95%CI 1.13-1.99) but had a nocebo index of 0.67.

LIMITATIONS

This study relied on multiple RCTs with subtle design differences.

CONCLUSIONS

This study identified several AEs that are likely the physiological result of antidepressants and many that likely represent nocebo effects. These results should inform clinical decision making and discussions with patients.

Predictive model of hydrogen trapping and bubbling in nanovoids in bcc metals

The interplay between hydrogen and nanovoids, despite long being recognized as a central factor in hydrogen-induced damage in structural materials, remains poorly understood. Here, focusing on tungsten as a model body-centred cubic system, we explicitly demonstrate sequential adsorption of hydrogen adatoms on Wigner-Seitz squares of nanovoids with distinct energy levels. Interaction between hydrogen adatoms on nanovoid surfaces is shown to be dominated by pairwise power-law repulsion. We establish a predictive model for quantitative determination of the configurations and energetics of hydrogen adatoms in nanovoids. This model, combined with the equation of states of hydrogen gas, enables the prediction of hydrogen molecule formation in nanovoids. Multiscale simulations, performed based on our model, show good agreement with recent thermal desorption experiments. This work clarifies fundamental physics and provides a full-scale predictive model for hydrogen trapping and bubbling in nanovoids, offering long-sought mechanistic insights that are crucial for understanding hydrogen-induced damage in structural materials.

Sleep and Attention in Alzheimer's Disease

Individuals with Alzheimer's disease (AD) present with a wide variety of symptoms, including sleep disruption and sleep disorders. Conversely, disordered sleep has been associated with an increased risk of developing AD. Both conditions individually have adverse effects on attention, which can be further divided into selective, sustained, divided, and alternating attention. The neural mechanisms underpinning sleep problems in AD involve the disruption of the circadian system. This review comprehensively discusses the types of attention impairments, the relationship between AD pathology and sleep disruption, and the effect of sleep issues on attention in AD. Recommendations for future research include addressing the lack of consistency among study designs and outcomes, and the need to continue exploring the biology of sleep and attention in AD.

The impacts of the quantum-dot confining potential on the spin-orbit effect

For a nanowire quantum dot with the confining potential modeled by both the infinite and the finite square wells, we obtain exactly the energy spectrum and the wave functions in the strong spin-orbit coupling regime. We find that regardless of how small the well height is, there are at least two bound states in the finite square well: one has the σ ^x [Formula: see text] = -1 symmetry and the other has the σ ^x [Formula: see text] = 1 symmetry. When the well height is slowly tuned from large to small, the position of the maximal probability density of the first excited state moves from the center to x ≠ 0, while the position of the maximal probability density of the ground state is always at the center. A strong enhancement of the spin-orbit effect is demonstrated by tuning the well height. In particular, there exists a critical height [Formula: see text], at which the spin-orbit effect is enhanced to maximal.

Using transcranial direct current stimulation to treat symptoms in mild cognitive impairment and Alzheimer's disease

Transcranial direct current stimulation (tDCS) has recently been investigated as a potential nonpharmacological treatment for individuals with mild cognitive impairment (MCI) and Alzheimer's disease (AD). A comprehensive literature search was performed on tDCS studies published until March 2017 using MEDLINE, Embase and PsychINFO databases. 12 articles with a total of 202 MCI or AD participants were included. Although ten of the 12 studies demonstrated positive findings with tDCS, two studies reported no effect on cognition. There was a wide range of methodological approaches used and in the cognitive functions measured. The variability in treatment response may be related to the heterogeneity in stimulation parameters including the site of stimulation, and cognitive assessments used. Patient-related factors including individual psychological, biological, and physiological status at the time of stimulation may also influence treatment response. We recommend that more comparative studies using similar patient factors and study parameters are needed in order to better understand the efficacy of tDCS in MCI and AD.

Peripheral inflammatory markers in Alzheimer's disease: a systematic review and meta-analysis of 175 studies

OBJECTIVES

Increasing evidence suggests that inflammation is involved in Alzheimer's disease (AD) pathology. This study quantitatively summarised the data on peripheral inflammatory markers in patients with AD compared with healthy controls (HC).

METHODS

Original reports containing measurements of peripheral inflammatory markers in AD patients and HC were included for meta-analysis. Standardised mean differences were calculated using a random effects model. Meta-regression and exploration of heterogeneity was performed using publication year, age, gender, Mini-Mental State Examination (MMSE) scores, plasma versus serum measurements and immunoassay type.

RESULTS

A total of 175 studies were combined to review 51 analytes in 13 344 AD and 12 912 HC patients. Elevated peripheral interleukin (IL)-1β, IL-2, IL-6, IL-18, interferon-γ, homocysteine, high-sensitivity C reactive protein, C-X-C motif chemokine-10, epidermal growth factor, vascular cell adhesion molecule-1, tumour necrosis factor (TNF)-α converting enzyme, soluble TNF receptors 1 and 2, α1-antichymotrypsin and decreased IL-1 receptor antagonist and leptin were found in patients with AD compared with HC. IL-6 levels were inversely correlated with mean MMSE scores.

CONCLUSIONS

These findings suggest that AD is accompanied by a peripheral inflammatory response and that IL-6 may be a useful biological marker to correlate with the severity of cognitive impairment. Further studies are needed to determine the clinical utility of these markers.

Evidence for Inflammation-Associated Depression

This chapter explores the evidence supporting inflammation-associated depression. Data to date suggest a bidirectional relationship between inflammation and depression wherein one process can drive the other. A wealth of animal and clinical studies have demonstrated an association between concentrations of pro-inflammatory cytokines - specifically interleukin (IL)-1β, IL-6, and tumor necrosis factor-α - and depressive symptoms. There is also evidence that this pro-inflammatory state is accompanied by aberrant inflammation-related processes including platelet activation factor hyperactivity, oxidative and nitrosative stress, and damage to mitochondria. These complex and interrelated mechanisms can collectively contribute to negative neurobiological outcomes that may, in part, underlie the etiopathology of depression. Mounting evidence has shown a concomitant reduction in both depressive symptoms and pro-inflammatory cytokine concentrations following treatment with pharmacological anti-inflammatory interventions. Taken together, the reviewed preclinical and clinical findings may suggest the existence of a distinct inflammatory subtype of depression in which these patients exhibit unique biochemical and clinical features and may potentially experience improved clinical outcomes with inflammation-targeted pharmacotherapy.

Peripheral cytokine and chemokine alterations in depression: a meta-analysis of 82 studies

OBJECTIVE

To conduct a systematic review and meta-analysis of studies that measured cytokine and chemokine levels in individuals with major depressive disorder (MDD) compared to healthy controls (HCs).

METHOD

The PubMed/MEDLINE, EMBASE, and PsycINFO databases were searched up until May 30, 2016. Effect sizes were estimated with random-effects models.

RESULT

Eighty-two studies comprising 3212 participants with MDD and 2798 HCs met inclusion criteria. Peripheral levels of interleukin-6 (IL-6), tumor necrosis factor (TNF)-alpha, IL-10, the soluble IL-2 receptor, C-C chemokine ligand 2, IL-13, IL-18, IL-12, the IL-1 receptor antagonist, and the soluble TNF receptor 2 were elevated in patients with MDD compared to HCs, whereas interferon-gamma levels were lower in MDD (Hedge's g = -0.477, P = 0.043). Levels of IL-1β, IL-2, IL-4, IL-8, the soluble IL-6 receptor (sIL-6R), IL-5, CCL-3, IL-17, and transforming growth factor-beta 1 were not significantly altered in individuals with MDD compared to HCs. Heterogeneity was large (I² : 51.6-97.7%), and sources of heterogeneity were explored (e.g., age, smoking status, and body mass index).

CONCLUSION

Our results further characterize a cytokine/chemokine profile associated with MDD. Future studies are warranted to further elucidate sources of heterogeneity, as well as biosignature cytokines secreted by other immune cells.

Econazole induces increases in free intracellular Ca2+ concentrations in human osteosarcoma cells

Econazole is an antifungal drug with different in vitro effects. However, econazole's effect on osteoblast like cells is unknown. In human MG63 osteosarcoma cells, the effect of econazole on intracellular Ca2+ concentrations ([Ca2+]i) was explored by using fura-2. At a concentration of 0.1 μM, econazole started to cause a rise in [Ca2+]i in a concentration-dependent manner. Econazole-induced [Ca2+]i rise was reduced by 74% by removal of extracellular Ca2+. The econazole-induced Ca2+ influx was mediated via a nimodipine-sensitive pathway. In Ca2+ free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca2+ ATPase, caused a [Ca2+]i rise, after which the increasing effect of econazole on [Ca2+]i was abolished. Pretreatment of cells with econazole to deplete Ca2+ stores totally prevented thapsigargin from releasing Ca2+. U73122, an inhibitor of phospholipase C, abolished histamine (an inositol 1,4,5-trisphosphate dependent Ca2+ mobilizer)-induced, but not econazoleinduced, [Ca2+]i rise. Econazole inhibited 76% of thapsigargin-induced store-operated Ca2+ entry. These findings suggest that in MG63 osteosarcoma cells, econazole increases [Ca2+]i by stimulating Ca2+ influx and Ca2+ release from the endoplasmic reticulum via a phospholipase C-independent manner. In contrast, econazole acts as a potent blocker of store-operated Ca2+ entry.

Energetic and kinetic dataset on interaction of the vacancy and self-interstitial atom with the grain boundary in α-iron

We provide the dataset of the vacancy (interstitial) formation energy, segregation energy, diffusion barrier, vacancy-interstitial annihilation barrier near the grain boundary (GB) in bcc-iron and also the corresponding interactive range. The vacancy-interstitial annihilation mechanisms in the bulk, near the GB and at the GB at across scales were given.

Extraordinary high ductility/strength of the interface designed bulk W-ZrC alloy plate at relatively low temperature

The refractory tungsten alloys with high ductility/strength/plasticity are highly desirable for a wide range of critical applications. Here we report an interface design strategy that achieves 8.5 mm thick W-0.5 wt. %ZrC alloy plates with a flexural strength of 2.5 GPa and a strain of 3% at room temperature (RT) and ductile-to-brittle transition temperature of about 100 °C. The tensile strength is about 991 MPa at RT and 582 MPa at 500 °C, as well as total elongation is about 1.1% at RT and as large as 41% at 500 °C, respectively. In addition, the W-ZrC alloy plate can sustain 3.3 MJ/m² thermal load without any cracks. This processing route offers the special coherent interfaces of grain/phase boundaries (GB/PBs) and the diminishing O impurity at GBs, which significantly strengthens GB/PBs and thereby enhances the ductility/strength/plasticity of W alloy. The design thought can be used in the future to prepare new alloys with higher ductility/strength.

Cannabinoids for the Treatment of Agitation and Aggression in Alzheimer's Disease

Alzheimer's disease (AD) is frequently associated with neuropsychiatric symptoms (NPS) such as agitation and aggression, especially in the moderate to severe stages of the illness. The limited efficacy and high-risk profiles of current pharmacotherapies for the management of agitation and aggression in AD have driven the search for safer pharmacological alternatives. Over the past few years, there has been a growing interest in the therapeutic potential of medications that target the endocannabinoid system (ECS). The behavioural effects of ECS medications, as well as their ability to modulate neuroinflammation and oxidative stress, make targeting this system potentially relevant in AD. This article summarizes the literature to date supporting this rationale and evaluates clinical studies investigating cannabinoids for agitation and aggression in AD. Letters, case studies, and controlled trials from four electronic databases were included. While findings from six studies showed significant benefits from synthetic cannabinoids—dronabinol or nabilone—on agitation and aggression, definitive conclusions were limited by small sample sizes, short trial duration, and lack of placebo control in some of these studies. Given the relevance and findings to date, methodologically rigorous prospective clinical trials are recommended to determine the safety and efficacy of cannabinoids for the treatment of agitation and aggression in dementia and AD.

Nanostructured fuzz growth on tungsten under low-energy and high-flux He irradiation

We report the formation of wave-like structures and nanostructured fuzzes in the polycrystalline tungsten (W) irradiated with high-flux and low-energy helium (He) ions. From conductive atomic force microscope measurements, we have simultaneously obtained the surface topography and current emission images of the irradiated W materials. Our measurements show that He-enriched and nanostructured strips are formed in W crystal grains when they are exposed to low-energy and high-flux He ions at a temperature of 1400 K. The experimental measurements are confirmed by theoretical calculations, where He atoms in W crystal grains are found to cluster in a close-packed arrangement between {101} planes and form He-enriched strips. The formations of wave-like structures and nanostructured fuzzes on the W surface can be attributed to the surface sputtering and swelling of He-enriched strips, respectively.

Using hydrological simulation to detect human-disturbed epoch in runoff series

Runoff in major rivers in China has been decreasing in recent decades, mainly due to climate change and human activity. River basin managers have a critical interest in detecting and diagnosing non-stationaries in runoff time series. Here we use a rainfall runoff model-based approach to identify the human-disturbed periods of the record. The method is applied to the Kuye River catchment, located in the Loess Plateau, China. The SimHyd model performs well for simulation of monthly natural discharges, and the method suggests that discernable human influence began in 1980. Anthropogenic effects were detectable several years earlier at the downstream stations than the upstream stations, consistent with pace and timing of soil and water conservation measures implemented across the Kuye River catchment.

Origin of the crossover in dynamics of the sub-Rouse modes at the same temperature as the structural α-relaxation in polymers

The nature of the liquid-glass transition remains an unsolved fundamental problem. One aspect is the striking change in dynamics of the structural α-relaxation generally observed at a temperature T(B) above Tg in all glass-formers. More intriguing in the case of polymers is that the change of dynamics occurs not only in the structural α-relaxation but also in the sub-Rouse modes, i.e. chain modes in between the α-relaxation and the Rouse modes. However, the nature of the dynamic crossover of the sub-Rouse modes remains unclear. In this paper, the dynamics of a series of poly(n-alkyl methacrylates) with different molecular weights and microstructures studied by mechanical spectroscopy are reported. We demonstrate that the sub-Rouse modes exhibit a similar crossover of dynamics at the same T(B) as the α-relaxation. This property shared by the two viscoelastic mechanisms is remarkable. By invoking the results from the studies using positron annihilation spectroscopy and adiabatic calorimetry, we show that both viscoelastic mechanisms are coupled to density, correlated with the change of the configuration entropy, and are intermolecularly cooperative. The time scale of sub-Rouse modes at T(B) of the polymers studied is approximately independent of molecular weight and micro-structure of the polymers studied. The findings enhance the understanding of the sub-Rouse modes and their manifestation in the viscoelasticity of polymers in the glass-rubber transition region.

A universal scaling law of grain chain elasticity under pressure revealed by a simple force vibration method

The grain contact force, the key player in determining the mechanical properties of grain materials, depends on the elastic modulus and deformation (δ) of grains. However, our knowledge on their relationship in a three-dimensional granular medium is limited mainly owing to the difficulty of realizing direct experimental investigation. Using a simple force vibration technique, we measure the dissipation spectra (the frequency response) of three kinds of grains with different elastic moduli under different pressures (to change the grain deformation). The dissipation spectra exhibit multiple resonant peaks, indicative of the resonance of grain chains with different lengths. This allows us to quantitatively characterize the elastic behaviors of grain chains. A universal correlation of the resonant frequency (f) of a grain chain with deformation is observed for all granular systems with different material properties (Young's modulus E, density ρ and Poisson's coefficient ν): f(2) ∝ δ(1/2)E/ρ(1 - ν). The deformation of the grain chain under pressure follows a p(2/3) pressure dependence. This general behavior suggests that the pressure-induced deformation of the grain chain under low-frequency weak shear vibration is overwhelmed by the nonlinear Hertzian contact elasticity.

Unruptured saccular aneurysm presenting migraine

Headache can be attributed to cranial or cervical vascular disorders including ischemic stroke or transient ischemic attack, non-traumatic intracranial hemorrhage, unruptured vascular malformation, arteritis, carotid-vertebral artery pain, and cerebral venous thrombosis. Here, we present a case report of unruptured saccular aneurysm with migraine. The patient was a previously healthy 32-year-old man with repeated episodes of headache for 6 years. Findings for computed tomography and magnetic resonance imaging of the head were normal. Head magnetic resonance angiography revealed a small, nodule-like protuberance seen in the anterior communicating artery. Based on his clinical features and ancillary examinations, the patient was diagnosed with migraine without aura. The patient subsequently underwent digital subtraction angiography (DSA), which revealed a 2-mm cystic protuberance in the superoposterior anterior communicating artery. The patient underwent stent-assisted coil embolization of the aneurysm. Subsequent DSA results indicated no recurrence of aneurysm and no recurrence of headache was reported after surgical treatment.

Obesity and bipolar disorder: synergistic neurotoxic effects?

Bipolar disorder (BD) is a disabling and chronic neuropsychiatric disorder that is typified by a complex illness presentation, episode recurrence and by its frequent association with psychiatric and medical comorbidities. Over the past decade, obesity has emerged as one of many comorbidities generating substantial concern in the BD population due to important prognostic implications. This comprehensive review details the bidirectional relationship between obesity and BD as evidenced by alterations in the structure and function of the central nervous system, in addition to greater depressive recurrence, cognitive dysfunction and risk of suicidality. Drawing on current research results, this article presents several putative mechanisms underlying the synergistic toxic effects and provides a framework for future treatment options for the obesity-BD comorbidity. There is a need for more large-scale prospective studies to investigate the bidirectional relationships between obesity and BD.

Possible s±-wave pairing evidenced by midgap surface bound states in Fe-pnictide superconductors

A phenomenological theory of tunneling spectroscopy for Fe-pnictide superconductors is developed by taking into consideration asymmetric interface scattering between particle and holes. It is shown that, consistent with anti-phase s(±)-wave pairing, appreciable zero-energy surface bound states exist on the [100] surface of Fe-pnictide superconductors. However, in contrast to the [110] bound states in d-wave cuprate superconductors, these bound states arise as a result of non-conservation of momentum perpendicular to the interface for tunneling electrons and the s(±) pairing, and hence they can only exist in a small window (~ ± 6°) in the orientation of edges near the [100] direction. Our results explain why a zero-bias conductance peak is often observed in tunneling spectroscopy and why, when it disappears, two coherent peaks show up. These results provide unambiguous signals to test for possible s(±)-wave pairing in Fe-pnictide superconductors.

A bacteria injection scheme for in situ bioaugmentation

This article presents an innovative design for inoculating the desired organisms to stratified geological layers at desired rates during in-situ bioaugmentation. The new delivery system consists of intermittent porous tubes connected in series with impermeable polyethylene tubes that run horizontally in each stratified layer of a contaminated aquifer. A bioaugmentation test using the new delivery system was conducted to inject an enriched culture of Escherichia coli (E. coli). Results of the test indicated that the distribution of E. coli through each porous tube was fairly uniform. A mathematical model previously developed to calculate the distribution of water flow through each porous tube was modified to calculate the distribution of E. coli. Geological layers often have different hydraulic conductivities. By controlling the permeability and the length of porous tubes placed in stratified layers, the new design provides a means to selectively deliver aqueous bacteria to various layers at desired rates according to aquifer heterogeneity.

Interplay between periodicity and nonlinearity of indirect excitons in coupled quantum wells

Inspired by a recent experiment of localization-delocalization transition (LDT) of indirect excitons in lateral electrostatic lattices (Remeika et al 2009 Phys. Rev. Lett. 102 186803), we theoretically investigate the interplay between periodic potential and nonlinear interactions of indirect excitons in coupled quantum wells. It is shown that the model involving both attractive two-body and repulsive three-body interactions can lead to a natural account for the LDT of excitons across the lattice when reducing lattice amplitude or increasing particle density. In addition, the observations that the smooth component of the photoluminescent energy increases with increasing exciton density and that the exciton interaction energy is close to the lattice amplitude at the transition are also qualitatively explained. Our model provides an alternative way of understanding the underlying physics of the exciton dynamics in lattice potential wells.

Plasmoid ejection and secondary current sheet generation from magnetic reconnection in laser-plasma interaction

Reconnection of the self-generated magnetic fields in laser-plasma interaction was first investigated experimentally by Nilson et al. [Phys. Rev. Lett. 97, 255001 (2006)] by shining two laser pulses a distance apart on a solid target layer. An elongated current sheet (CS) was observed in the plasma between the two laser spots. In order to more closely model magnetotail reconnection, here two side-by-side thin target layers, instead of a single one, are used. It is found that at one end of the elongated CS a fanlike electron outflow region including three well-collimated electron jets appears. The (>1 MeV) tail of the jet energy distribution exhibits a power-law scaling. The enhanced electron acceleration is attributed to the intense inductive electric field in the narrow electron dominated reconnection region, as well as additional acceleration as they are trapped inside the rapidly moving plasmoid formed in and ejected from the CS. The ejection also induces a secondary CS.

Oxidative degradation of propachlor by ferrous and copper ion activated persulfate

The process of in situ chemical oxidation (ISCO) by persulfate (S(2)O(8)(2-)) can be accelerated by metal ion activation, which more effectively degrades subsurface pollutants by enhancing sulfate radical (SO(4)(-)) generation. This study compared the results of propachlor degradation by Cu(2+) and Fe(2+) activated persulfate and revealed differing degradation kinetics and mechanisms between the two types of activation system. The activation of persulfate by Fe(2+) ions generally resulted in rapid degradation in the early stage, but was accompanied by a dramatic decrease in efficiency due to the rapid depletion of Fe(2+) by the sulfate radicals generated. In contrast, the Cu(2+) activated persulfate had a longer lasting degradation effect and a proportionally greater degradation enhancement at elevated Cu(2+) concentrations. An optimal Fe(2+) concentration should be sought to activate the persulfate, as a high Fe(2+) concentration of 2.5mM or above, as was used in this study, may inhibit propachlor degradation due to the competitive consumption of sulfate radicals by the excess Fe(2+) ions. Higher temperatures (55°C compared with 30°C) resulted in enhanced metal activation, particularly with the Cu(2+) activated system. Furthermore, acidic conditions were found to be more favorable for propachlor degradation by metal activated persulfate. The ecotoxicity of degraded propachlor samples, which was indicated by average well color development (AWCD) for its microbial community activity, was confirmed to be decreased during the degradation processes with these two ions activated persulfate.

Kinetics and mechanism of propachlor reductive transformation through nucleophilic substitution by dithionite

Chloroacetanilide herbicides are extensively used in the control of weeds and have widely resulted in nonpoint contamination of groundwater and soil resources. In the attempt to achieve better remediation for herbicide-contaminated resources, we investigated the reductive transformation of propachlor through nucleophilic substitution by dithionite (S(2)O(4)(2-)). Results showed that propachlor underwent rapid dechlorination in the presence of dithionite. The reaction was of second-order kinetics and strongly influenced by pH and temperature. At pH 7.0 and temperature 308K, the rate constant of propachlor dechlorination was estimated at 123.4±0.7M(-1)h(-1). Within the pH range tested (3.0-9.5), higher pH promoted the ionization of dithionite, resulting in a more active nucleophilic reagent of S(2)O(4)(2-) to enhance the propachlor transformation rate. Similarly, higher reaction temperature overcame the activation barrier of steric hindrance in propachlor structure and accelerated the excitation of dithionite, in which higher rate constants of propachlor reductive dechlorination were obtained. Dechlorination was found to be the first and necessary step of propachlor nucleophilic substitution by dithionite. Sulfur nucleophile substituted compounds, including propachlor dithionite, propachlor ethanesulfonic acid (ESA), and hydroxyl propachlor, were identified as the dechlorination products of propachlor, indicating bimolecular nucleophilic substitution (S(N)2) as the mechanism for propachlor transformation initiated by dithionite.

Genetic evaluation and management of fetal chylothorax: review and insights from a case of Noonan syndrome

Fetal chylothorax is one of a very few syndromes that can be treated in utero with thoracoamniotic shunting or pleurodesis by OK-432 as two major therapeutic modalities. We report on a fetus with Noonan syndrome and a missense mutation c.182A > C (p.Asp61Ala) of PTPN11 who responded poorly to antenatal pleurodesis by OK-432. Based on our previous publication and this case study, we propose that fetal chylothorax of a distinct genetic origin may respond poorly to OK-432 pleurodesis.

Photodegradation of polycyclic aromatic hydrocarbon pyrene by iron oxide in solid phase

To better understand the photodegradation of polycyclic aromatic hydrocarbons (PAH) in solid phase in natural environment, laboratory experiments were conducted to study the influencing factors, kinetics and intermediate compound of pyrene photodegradation by iron oxides. The results showed that the pyrene photodegradation rate followed the order of alpha-FeOOH>alpha-Fe(2)O(3)>gamma-Fe(2)O(3)>gamma-FeOOH at the same reaction conditions. Lower dosage of alpha-FeOOH and higher light intensity increased the photodegradation rate of pyrene. Iron oxides and oxalic acid can set up a photo-Fenton-like system without additional H(2)O(2) in solid phase to enhance the photodegradation of pyrene under UV irradiation. All reaction followed the first-order reaction kinetics. The half-life (t(1/2)) of pyrene in the system showed the higher efficiencies of using iron oxide as photocatalyst to degrade pyrene. Intermediate compound pyreno was found during photodegradation reactions by gas chromatography-mass spectrometry (GC-MS). The photodegradation efficiency for PAHs in this photo-Fenton-like system was also confirmed by using the contaminated soil samples. This work provides some useful information to understand the remediation of PAHs contaminated soils by photochemical techniques under practical condition.

Effect of Celecoxib on Ca2+Fluxes and Proliferation in MDCK Renal Tubular Cells

The effect of celecoxib on renal tubular cells is largely unexplored. In Madin Darby canine kidney (MDCK) cells, the effect of celecoxib on intracellular CaCa2+ concentration ([Ca2+]i) and proliferation was examined by using the Ca(2 +)-sensitive fluorescent dye fura-2 and the viability detecting fluorescent dye tetrazolium, respectively. Celecoxib (> or =1 micro M) caused an increase of [CaCa2+]i in a concentration-dependent manner. Celecoxib-induced [CaCa2+]i increase was partly reduced by removal of extracellular CaCa2+. Celecoxib-induced CaCa2+ influx was independently suggested by MnCa2+ influx-induced fura-2 fluorescence quench. In Ca(2 +)-free medium, thapsigargin, an inhibitor of the endoplasmic reticulum Ca(2 +)-ATPase, caused a monophasic [CaCa2+]i increase, after which celecoxib only induced a tiny [CaCa2+]i increase; conversely, pretreatment with celecoxib completely inhibited thapsigargin-induced [CaCa2+]i increases. U73122, an inhibitor of phospholipase C, abolished ATP (but not celecoxib)-induced [CaCa2+]i increases. Overnight incubation with 1 or 10 micro M celecoxib decreased cell viability by 80% and 100%, respectively. These data indicate that celecoxib evokes a [CaCa2+]i increase in renal tubular cells by stimulating both extracellular CaCa2+ influx and intracellular CaCa2+ release and is highly toxic to renal tubular cells in vitro.

Chitosan/Cellulose Acetate Microspheres Preparation and Ranitidine Release In Vitro

New microspheres containing hydrophilic core and hydrophobic coating as a controlled-release system with no toxic reagents were proposed. Water in oil in water (W/O/W) emulsion and solvent evaporation methods were used to make chitosan/ cellulose acetate (CCA) microspheres sized 200 - 400 microm. Ranitidine hydrochloride, as a model drug, was investigated for its release properties in vitro. The loading efficiency and release rate of ranitidine were affected by chitosan concentration and molecular weight. Higher loadings were obtained at lower concentrations in the interval of 1% to 2%. With chitosan at a 2% concentration microspheres could be obtained with more spherical appearance, smaller size, and higher ranitidine loading efficiency microspheres than at other concentrations. Among the different molecular weight chitosan (47, 145, 308, 499, and 1130 KD) microspheres, the high molecular weight chitosan (1130 KD) microspheres had relatively high loading efficiency (10%). Molecular weight and concentration of chitosan as well as the size of microspheres affected the release of ranitidine. Microspheres smaller than 280 microm released the drug faster than did the bigger by about 10%. The optimal condition for the preparation of the microspheres was chitosan concentration 2%, molecular weight 1130 KD. The ranitidine release from the microspheres was 30% during 48 h in phosphate-buffer saline medium.

Characterization of reflection intermittency in a composite granular chain

The physical factors controlling the power-law behavior of impact energy in a composite granular chain remain elusive. Based on event-driven simulations and the on-off intermittency of wave reflections, we obtain the probability distribution functions of the waiting time tau and the energy leakage DeltaE . They exhibit lognormal distributions, which together with the relationship between DeltaE and tau allow one to explain directly the power-law behavior of the confined energy. This work may be extended to higher dimensions and help us understand the complex dynamics in granular materials.

Effect of alumina on photocatalytic activity of iron oxides for bisphenol A degradation

To study the photodegradation of organic pollutants at the interface of minerals and water in natural environment, three series of alumina-coupled iron oxides (Al(2)O(3)-Fe(2)O(3)-300, Al(2)O(3)-Fe(2)O(3)-420, and Al(2)O(3)-Fe(2)O(3)-550) with different alumina fraction were prepared and characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) and Barret-Joyner-Halender (BJH), and Fourier transform infrared spectra (FTIR). The XRD results showed that existence of alumina in iron oxides could hinder the formation of maghemite and hematite, and also the crystal transformation from maghemite to hematite during sintering. It has been confirmed that the BET surface area and micropore surface area of Al(2)O(3)-Fe(2)O(3) catalysts increased with an increased dosage of alumina and with decreased sintering temperature. The pore size distribution also depended on the fraction of alumina. Furthermore, all Al(2)O(3)-Fe(2)O(3) catalysts had a mixed pore structure of micropore, mesopore and macropore. FTIR results showed that FTIR peaks attributable to Fe-O vibrations of maghemite or hematite were also affected by alumina content and sintering temperature. It was confirmed that the crystal structure and crystalline, the surface area and pore size distribution of Al(2)O(3)-Fe(2)O(3) catalysts depend strongly on the content of alumina and also sintering temperature. Bisphenol A (BPA) was selected as a model endocrine disruptor in aquatic environment. The effects of alumina on the photocatalytic activity of iron oxides for BPA degradation were investigated in aqueous suspension. The experimental results showed that the dependence of BPA degradation on the alumina content was attributable to the crystal structure, crystalline and also the properties of their surface structures. It was confirmed that the mixed crystal structure of maghemite and hematite could achieve the higher photocatalytic activity than maghemite or hematite alone.

Crossover in the power-law behavior of confined energy in a composite granular chain

We present a numerical study of the impact energy decay in a composite granular chain containing two heavy and one light sections. We observe a marked crossover in the power-law behavior of the impact-energy decay. The average reflection frequency first increases with a decreasing acceleration, and arrives at its maximum at "crossing" time then decays almost exponentially. The analysis demonstrates that this phenomenon is related to the structural transition from compression to dilation state in both heavy-particle sections. The further calculations suggest the dependence relation of the power-law exponent (gammacb) in compression state on the mass ratio (m2/m1) and the Hertz law exponent (n) of the composite granular chain gammacb approximately (m2/m1)1/(n+1).

B-group vitamins, MTHFR C677T polymorphism and carotid intima-media thickness in clinically healthy subjects

OBJECTIVE

Plasma B-group vitamins and age may affect the carotid intima-media thickness (IMT) in subjects with different 677TT genotype of the methylenetetrahydrofolate reductase (MTHFR) gene.

DESIGN

A hospital-based cross-study.

SETTING

Genomic and Vascular Center, Changhua Christian Hospital, Changhua, Taiwan.

SUBJECTS

Five hundred and forty-one clinically healthy subjects.

INTERVENTION

Fasting plasma, homocysteine (Hcy), vitamin B(6), vitamin B(12), folate and B-mode carotid ultrasound.

RESULTS

MTHFR genotype, plasma concentrations of folate, vitamin B(6) and vitamin B(12) and age were significantly correlated to the plasma Hcy concentration. MTHFR 677TT carriers had higher concentrations of Hcy than did subjects with the CC and CT genotypes. Age, sex, body mass index and plasma Hcy were independent contributors to increase carotid IMT. However, with stratification by mean value of age and B-group vitamins concentrations, we found that at advanced age, lower plasma folate and vitamin B(12) were three risk factors involved in the enhancing effect of the MTHFR 677TT genotype on the increase of plasma Hcy and carotid IMT.

CONCLUSION

MTHFR 677TT-related carotid atherosclerosis was only identified in healthy elderly subjects with lower level of plasma folate and vitamin B(12).

SPONSORSHIP

Changhua Christian Hospital.

Development of a degradable cement of calcium phosphate and calcium sulfate composite for bone reconstruction

A new type of composite bone cement was prepared and investigated by adding calcium sulfate (CS) to calcium phosphate cement (CPC). This composite cement can be handled as a paste and easily shaped into any contour, which can set within 5-20 min, the setting time largely depending on the liquid-solid (L/S) ratio; adding CS to CPC had little effect on the setting time of the composite cements. No obvious temperature increase and pH change were observed during setting and immersion in simulated body fluid (SBF). The compressive strength of the cement decreased with an increase in the content of CS. The degradation rate of the composite cements increased with time when the CS content was more than 20 wt%. Calcium deficient apatite could form on the surface of the composite cement because the release of calcium into SBF from the dissolution of CS and the apatite of the cement induced the new apatite formation; increasing the content of CS in the composite could improve the bioactivity of the composite cements. The results suggested that composite cement has a reasonable setting time, excellent degradability and suitable mechanical strength and bioactivity, which shows promising prospects for development as a clinical cement.

Calculations of cellular microdosimetry parameters for alpha particles and electrons

The cellular microdosimetry parameters including the cellular S-value and the single-event specific energy distribution for alpha particles and electrons are important in radiation dosimetry and biology. These parameters may be used to determine the relative biological effectiveness of radiations in the boron neutron capture therapy. In the present work, such parameters were calculated for different source to target region combinations, i.e. cell surface, cytoplasm, nucleus and cell. Calculations were made using a semi-analytical model that simulated the emission of alpha particles or electrons by the Monte Carlo method and calculated the energy imparted to the target volume by the analytical method. Delta particle equilibrium and partial delta particle equilibrium were applied to alpha particles and electrons, respectively. Range-energy relations were employed to determine the incident and emerging energies of the primary particles. For electrons, the fraction in the energy loss resulting from the generation of bremsstrahlung and high-energy secondary electrons was estimated. The energy loss straggling of electrons entering and leaving a target volume was also estimated. Calculated cellular S-values were compared to corresponding data of the MIRD Committee. Calculated single-event specific energy distributions were also compared to results calculated using the Penelope code.

Epidemiological and genetic studies of myotonic dystrophy type 1 in Taiwan

To investigate the prevalence and genetic characteristics of myotonic dystrophy type 1 (DM1) in Taiwan, DM-suspected patients and their families identified during the period of 1990-2001 had their clinical records reevaluated and the CTG repeat sizes at the DM1 locus examined. A total of 96 subjects belonging to 26 families were identified as DM1 patients, which gave a minimal disease prevalence of 0.46/100,000 inhabitants. Clinical anticipation was frequently observed in affected families, even in some parent-child pairs with transmission contraction of the CTG repeat size. The inverse correlation between age at onset and CTG repeat length was significant only in patients with small expansions. In addition, a DM1 carrier with a childhood-onset son was found to have CTG length heterogeneity in the range of 40-50, indicating that premutation alleles could be unstable during gametogenesis as well as in somatic tissues. Our data demonstrated that DM1 is a rare disease in Taiwan and showed that transmission contraction of repeat size is more likely to occur in alleles with large repeats.

Electron- or hole-assisted reactions of H defects in hydrogen-bonded KDP

We present an ab initio study of the stability and defect reactions of neutral and charged H interstitial (H(i)) and H vacancy (H(v)) in KH2PO4 (KDP). We find that while there is no interaction between the neutral H(i) and the host, the addition of an electron leads to the ejection of a H host atom and the subsequent formation of an interstitial H2 molecule and a H(v). In sharp contrast, the addition of a hole results in the formation of a hydroxyl bond. Thus, H(i) in both charged states severs the H-bonded network. For the H(v), the addition of a hole leads to the formation of a peroxyl bridge. The neutral H(i) and the positively charged H(v) induce states in the gap. The results elucidate the underlying atomic mechanism for the defect reactions suggested by experiment.

[Study on the interaction between sparfloxacin and serum albumins by fluorescence]

The binding reaction between sparfloxacion (SPFX) and bovine serum albumin (BSA) or chicken egg albumin (CEA) in aqueous was studied using fluorescence and absorption spectra. Their binding constants are KCEA = 8.29 x 10(6) and KBSA = 4.41 x 10(7), and the binding sites are nCEA = 0.558, nBSA = 0.793 respectively. The action distances (RCEA = 1.99 nm, RBSA = 2.09 nm) and energy transfer efficiencies (ECEA = 0.766, EBSA = 0.714) between donor-acceptor and SPFX were obtained by Förster's nonradiative energy transfer mechanism. The experiment demonstrated that the higher the temperature is, the lower the slopes of quenching curves of BSA and CEA are in presence of different amounts of SPFX. It is confirmed that the combination for SPFX with BSA or CEA is a single static quenching process, their interaction may be interpreted with energy transfer mechanism. Through binding reaction of the two albumins with SPFX, the biological effects and action mechanism of SPFX with albumins in vivo were discussed.