Interdiffusion and Carrier Recombination in High Intensity Transient Gratings

Transient grating (TG) experiments were performed to study carrier diffusion and recombination in amorphous silicon films (a-Si:H) at high light intensities using 8 ns pulses from a frequency-doubled Nd:YAG laser. The ambipolar diffusion coefficients reached about 10−2cm2/s, which is 2 orders of magnitude larger than the steady-state value. Similar results were obtained in intrinsic, p-, and n-doped a-Si:H films, indicating that the diffusion coefficients in all cases reflect the near band edge mobility of the slower carriers, that is holes. In particular, the p-type sample shows an initially fast, then a slow grating efficiency decay, consistent with dispersive transport.

Activity of a novel dual PI3-kinase/mTOR inhibitor NVP-BEZ235 to enhance antitumor activities of gemcitabine and EMAP II in pancreatic cancer

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Background: Gemcitabine (Gem, G) has limited benefits as single agent or in combination for pancreatic ductal adenocarcinomas (PDACs). The phosphatidylinositol-3-kinase (PI3K)/AKT and mammalian target of rapamycin (mTOR) signaling pathways are frequently dysregulated in diverse human cancers including PDAC. NVP-BEZ235 (BEZ, B) is a novel dual PI3K/mTOR inhibitor that has been shown to have antitumor activity in multiple tumor types. Endothelial monocyte activating polypeptide II (EMAP, E) is an antiendothelial and antiangiogenic agent that enhances Gem and docetaxel activity in PDAC. We tested the combination benefits of BEZ and Gem in addition to EMAP in experimental PDAC.

Methods: In vitro cell proliferation and protein expression were analyzed by WST-1 assay and Western blotting. In vivo animal survival experiments were performed in NOD-SCID PDAC xenografts.

Results: Cultured cells of PDAC (AsPC-1), endothelial (HUVECs), and fibroblast origin (WI-38) all expressed AKT and mTOR protein. BEZ inhibited in vitro cell proliferation of AsPC-1 and HUVECs cells, with some additive effects in combination with Gem or EMAP, after 72 hours of incubation. In AsPC-1, treatment of BEZ (100 nM), Gem (100 nM) and EMAP (1 μM) caused 34, -7, -16, 62, 51, 3, and 59 percent inhibition in proliferation in the B, G, E, B+G, B+E, G+E and B+G+E groups. In HUVECs, percent inhibition in proliferation was 35, 33, 15, 55, 35, 31 and 53 in the B, G, E, B+G, B+E, G+E and B+G+E groups, respectively. Compared to controls (median survival: 16 days), an animal survival increase after BEZ and EMAP therapy alone (both 21 days) and Gem therapy alone (28 d) was observed. Further increases in survival occurred in combination therapy groups B+G (30 d, p=0.007), B+E (27 d, p=0.02), G+E (31 d, p=0.001) and B+G+E (33 d, p=0.004).

Conclusions: Bez has experimental PDAC antitumor activity in vitro and in vivo that is further enhanced by combination of Gem and EMAP. These findings demonstrate advantages of combination therapy strategies targeting multiple pathways in pancreatic cancer treatment.

No significant financial relationships to disclose.

Augmenting chemotherapy response through EMAP II combination in experimental pancreatic cancer

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Background: Gemcitabine (Gem), the most active drug for locally advanced, non-operable and metastatic PDAC, has limited benefits as single agent or in combination. Endothelial monocyte activating polypeptide II (EMAP, E) enhances Gem effects in PDAC. We evaluated the antitumor activities of EMAP in combination with doxorubicin (Dox) or docetaxel (DT) in PDAC.

Methods: In vitro cell proliferation, protein expression and apoptosis were analyzed by WST-1 assay, Western blotting and FACS analysis. In vivo local tumor growth and animal survival experiments were performed in murine xenografts.

Results: In vitro PDAC cell proliferation was not affected by EMAP, compared to a small inhibition by Dox, DT and Gem. EMAP combination to these agents did not increase the antiproliferative effects. In endothelial cells (ECs), EMAP, Dox, DT and Gem all inhibited proliferation (59, 79, 96 and 85% at 10 μM, respectively); addition of EMAP caused additive antiproliferative effects. In PDAC cells, no agent caused measurable apoptosis, but in ECs all agents either alone or in combination increased the apoptosis. In vivo, Dox, DT, Gem and EMAP all decreased local tumor growth, and addition of EMAP enhanced inhibitory effects of DT and Gem, but not of Dox (92, 63, 60, 42, 73, 85 and 68 % inhibition after Dox, DT, Gem, E, Dox+E, DT+E and Gem+E, respectively); DT followed by Gem led to 72% inhibition without EMAP, and to 99% with EMAP (p=0.001). Inhibition of intra-tumoral proliferative activity and increase of apoptotic index were enhanced in all EMAP combination groups. Compared to controls (median survival: 21 days), EMAP (20 d) had no, but Dox (31 d) and DT (35 d) had extended survival benefit. EMAP enhanced the DT effect (44 d, p=0.009) but not that of Dox (31 d, p=0.04). In a sequential therapy experiment, median survival after controls, Gem, DT, Gem followed by DT, DT followed by Gem, Gem+E, DT+E, Gem/DT+E and DT/Gem+E was 17, 25, 29, 39, 39, 28, 35, 34 and 41 days, respectively.

Conclusions: The antiendothelial agent EMAP enhances antitumor effects of not just gemcitabine. Therefore, combination approaches with EMAP-like agents could render other drugs such as taxanes or their doublets sufficiently effective for clinical applications in PDAC therapy.

No significant financial relationships to disclose.

A comparison of competing lymph node staging schemes in resectable biliary cancer

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Background: New schemes for lymph node (LN) staging have been proposed to improve upon the AJCC TNM cancer staging convention. We compared AJCC N0/N1 staging with the LN ratio and logarithmic odds systems in predicting overall survival (OS) in resectable biliary cancer patients, including cancer of the gallbladder, extrahepatic bile duct (EHBD), and ampulla of Vater (AOV).

Methods: In a large, multiinstitutional U.S.-based biliary cancer data set, we identified 4,288 nonmetastatic resectable biliary cancer patients diagnosed between 1988 and 2006. We compared each subject's AJCC N stage with the two novel staging schemes. We split patients into two groups above or below the median for the two novel staging schemes and analyzed OS. Our comparison metric was the log-rank chi-squared statistic. As a baseline comparator, we included the median number of LNs resected.

Results: Median (range) of follow- up was 2.5 years (1 month–19 years), with an overall median survival of 2.0 years (95% CI: 2.0–2.1 years). For all biliary patients combined, we found that the AJCC N0/N1 system and LN ratio schemes performed similarly. For gallbladder cancers (N= 1,340), LN ratio showed higher OS prediction utility, whereas in EHBD (N= 1,083) and AOV cancers (N= 1,865), AJCC staging was superior among competing methods.

Conclusions: The LN ratio method is comparable with AJCC N staging for OS prediction, although the AJCC scheme is superior in two of three biliary cancers. We conclude that AJCC staging remains adequate for staging biliary cancers given the newer staging proposals.

[Table: see text]

No significant financial relationships to disclose.

Local piezoelectric properties of ZnO thin films prepared by RF-plasma-assisted pulsed-laser deposition method

Zinc oxide (ZnO) thin films were grown on uncoated and zinc-coated Corning glass substrates by pulsed-laser deposition (PLD). X-ray diffraction measurements revealed that the as-deposited films are polycrystalline having preferential orientation along the [0002] and [[Formula: see text]] directions. Transmittance spectroscopy verified that the as-deposited films are transparent with a direct bandgap of about 3.28 eV at room temperature. Piezoresponse imaging and local hysteresis loop acquisition were performed to characterize the piezoelectric and possible ferroelectric properties of the films. The out-of-plane (effective longitudinal, d(parellel)) and in-plane (effective shear, d(perpendicular)) coefficients were estimated from the local piezoresponse based on the comparison with LiNbO(3) single crystals. Measurements of all three components of piezoresponse (one longitudinal and two shear signals) allowed constructing piezoelectric maps for polycrystalline ZnO and to relate the variation of piezoelectric properties to the crystallographic and grain structure of the films. A shifted piezoresponse hysteresis loop under high voltages hints at the possible pseudoferroelectricity, as discussed recently by Tagantsev (2008 Appl. Phys. Lett. 93 202905).

Depression and anxiety in patients undergoing herniated disc surgery: relevant but underresearched - a systematic review

BACKGROUND

An association between depression and anxiety and musculoskeletal disorders has been consistently reported in the past years. This article provides a systematic overview of the literature on the prevalence rates of depression and anxiety in patients undergoing surgery for a herniated disc.

METHODS

A systematic literature search was conducted in the following electronic databases: PubMed, PsycINFO, Web of Science, Cochrane Library and PSYNDEXplus. The identified articles were evaluated for prevalence rates of depression and anxiety, methodological issues, change of depression and anxiety over time, and major findings on the impact of depression and anxiety on patients undergoing disc surgery.

RESULTS

Fourteen studies were identified. Prevalence rates for depression and anxiety in patients undergoing disc surgery varied between 21.5% and 49.3% before and between 4.1% and 79.6% after disc surgery. The study designs, the use of assessment instruments and cut-off values varied greatly. Depression and anxiety decreased within the population of disc surgery patients over time. Depression and anxiety were found to have a great impact on the postoperative outcome of surgery, return to work, analgesia abuse, pain experience, and abnormal illness behaviour.

CONCLUSIONS

Little research has been done to investigate depression and anxiety in patients undergoing surgery for a herniated disc. Evidently disc surgery patients are at higher risk of suffering from depression and anxiety than the general population. The review outlines the importance for clinicians to be more sensitive to psychological concerns in patients undergoing disc surgery. Psychological assessment and assistance from mental health professionals should be considered during the hospital stay and rehabilitation period, depending on local feasibility. Further investigations are necessary to examine whether the implementation of a multidisciplinary in-patient treatment program will improve postoperative outcome in patients undergoing intervertebral disc surgery.

Anxiety and depression in cancer patients compared with the general population

The objective of this study was to compare the prevalence of anxiety and depression in cancer patients with the prevalence found in the general population, using the Hospital Anxiety and Depression Scale (HADS). Participants were 1529 cancer patients treated between 2002 and 2004 in Germany and 2037 persons from the German general population. In the cancer patients, the risk of psychiatric distress was nearly twice that of the general population. While for older age groups (61 years and above) there were only small differences between cancer patients and the general population, the differences in both scales were high for young persons. There were differences between the HADS mean scores of the patients with different tumour localisations, with high values for brain cancer and low scores for prostate cancer. The influence of the tumour stage on anxiety and depression was weak. However, depression scores of patients with a survival time less than 1 year were elevated. The results show that large sample sizes are necessary to evaluate the psychological situation of cancer patients, and that age and gender differences must be taken into account when several samples are compared.

[Psychosocial support care wanted and actually received by patients with cancer. Gender-specific differences]

BACKGROUND AND OBJECTIVES

Professional psychosocial support of patients with cancer is an essential component of the entire process of medical care of these patients. But so far gender specific differences have only rarely been investigated. Yet some studies have suggested that there are differences between male and female patients regarding their psychological burden and their use of psychosocial support facilities. This article discusses the latter issue, based on empirical data.

METHODS

At the beginning of their treatment (t1) the patients were asked to answer a questionnaire exploring their needs and wishes regarding medical and psychological care, as well as regarding self-support. There were 252 patients (60% males; mean age of males = 60.1 ; mean age of females = 55.5) with different kinds of cancer (39.7% of males had prostate cancer; 26.7% of females had breast cancer). The follow-up (t2) took place half a year after t1. As part of the follow-up questionnaire data regarding the meeting of the individual patient's needs was collected. Standardized scales were used (t1, t2), as well as a clinical interview (SKID) (t1), which recorded psychological co-morbidity.

RESULTS

The need for support was found not to differ significantly between the genders but depended on the grade of co-morbidity and on the particular group of supporting professionals, respectively. Most frequently, within the overall condition "medical support" the patients' need for support (t1) and the actually received support (t2) were found to be coincident (85.7 - 94.2 %) for women as for men. Particularly with regard to psychological and social care, multivariate analysis revealed the need for care (t1) being a predictor of actually received support (t2). Especially within the group of women the factor "living alone" was found to explain the congruence between the need for care and the received support.

CONCLUSION

Few gender-specific differences regarding need for care and actually received support have been found within this cohort of male and female patients with cancer. It is a unclear to what degree such differences could be due to the design of the study. It is important to assess the patient's wishes and needs for multiprofessional care at the beginning of cancer treatment. In addition the family and social situation must be taken into account.

Optically Clear Endometrial Nuclei

The ultrastructure of optically clear endometrial nuclei is presented. These nuclear alterations have been found in spontaneous abortion, term pregnancy, endometriosis, and uterine choriocarcinoma.

Parity violation constraints using cosmic microwave background polarization spectra from 2006 and 2007 observations by the QUaD polarimeter

We constrain parity-violating interactions to the surface of last scattering using spectra from the QUaD experiment's second and third seasons of observations by searching for a possible systematic rotation of the polarization directions of cosmic microwave background photons. We measure the rotation angle due to such a possible "cosmological birefringence" to be 0.55 degrees +/-0.82 degrees (random) +/-0.5 degrees (systematic) using QUaD's 100 and 150 GHz temperature-curl and gradient-curl spectra over the spectra over the multipole range 200<l<2000, consistent with null, and constrain Lorentz-violating interactions to <2 x 10;{-43} GeV (68% confidence limit). This is the best constraint to date on electrodynamic parity violation on cosmological scales.

[The role of next of kin in medical decision-making--empirical findings from haemato-oncological diseases]

AIM OF THE STUDY

Models of shared decision making in the patient-doctor relationship are attracting increasing attention. A recent study focuses on the so far inadequate attention paid to the role of next of kin. It was examined in which decision areas next of kin of haematological cancer patients were included, further what support next of kin could provided and finally which factors encouraged the participation of next of kin in that process.

METHODS

From 2006-2008 empirical data were collected from hemato-oncological patients undergoing treatment as well as from their families. The participating family members of patients were mailed questionnaires based on the patient sample (designation of a family member by the patient: 118/177 or 66.7%) on average half of a year following the patient's (in- or outpatient) treatment. The response rate of the participants was 67.8% (80/118). Of the respondents, 65% were spouses or partners of the patients, the average age was 53.9 years, and 66.3% were female.

RESULTS

Family members think it makes sense for them to take an active part in medical decisions affecting their loved ones and a majority of them reported having participated in decision-making processes concerning a variety of issues. Being involved in their loved one's discussions with their doctors has a significant influence on this. Family members' level of education was the only clear predictor for participation in discussions with doctors that could be isolated.

CONCLUSION

It is clear that family members, especially spouses and partners, consider it meaningful to participate in medical decisions affecting their loved ones, and that they want to be able to do this in the clinical context. One limitation that must be mentioned is that due to the small size of the sample and an approach that focused on initial exploration, the results should be interpreted as a point of orientation. Further studies should look in more detail at how inner family structures play a role in patient-doctor shared decision-making, as well as the concrete conditions and implications that play a role in family members' participation in this process, i.e., adherence to "doctor's orders" and possible decision-making conflicts on the part of the patient.

Hospital anxiety and depression scale cutoff scores for cancer patients in acute care

The aim of this study was to determine optimal cutoff scores for the Hospital Anxiety and Depression Scale (HADS) when used in evaluating cancer patients in acute care. A total of 689 cancer patients were assessed during their first days of in-patient treatment, using the structured clinical interview for DSM and the HADS. Statistical analysis was performed using ROC curves. A total of 222 patients (32%) had a mental disorder. The area under the curve was the best in the total scale of the HADS, namely 0.73. With a score of ⩾13, it is possible to detect 76% of the cases with a specificity of .60, whereas 95% of the cases can be detected with a score of ⩾6 (specificity 0.21). With scores of ⩾16 and ⩾22, recommended by the test authors for primary care, only 59 and 30% of the comorbid cancer patients are indicated. Lower HADS cutoff scores when preferable when evaluating cancer patients than are recommended for use in primary care. When using HADS in clinical practice and epidemiological studies, it is important to decide whether, for the task at hand, high detection rates of affected patients or low misclassification rates are more important.