Transcription Independent Stimulation of Telomerase Enzymatic Activity by HTLV-I Tax Through Stimulation of IKK

The persistence and spreading of HTLV-I infected cells relies upon their clonal expansion through cellular replication. The development of adult T cell leukemia (ATLL) occurs decades following primary infection by HTLV-I. Moreover, identical provirus integration sites have been found in samples recovered several years apart from infected individuals. These observations suggest that infected cells persist in the host for an extended period of time. To endure long term proliferation, HTLV-I pre-leukemic cells must acquire critical oncogenic events, two of which are the bypassing of apoptosis and replicative senescence. In the early stages of disease, interleukin-2 (IL-2)/IL-2R signaling likely plays a major role in combination with activation of anti-apoptotic pathways. Avoidance of replicative senescence in HTLV-I infected cells is achieved through reactivation of human telomerase (hTERT). We have previously shown that HTLV-I viral Tax transcriptionally activates the hTERT promoter. In this study we demonstrate that Tax can stimulate hTERT enzymatic activity independently of its transcriptional effects. We further show that this occurs through Tax-mediated NF-KB activating functions. Our results suggest that in ATLL cells acquire Tax-transcriptional and post-transcriptional events to elevate telomerase activity.

Validation of a simple tool for anxiety trait screening in children presenting for surgery

Background.

Screening for preoperative anxiety is an important challenge during the preoperative period. The aim of our study was to validate the faces scale used to detect anxiety trait in children.

Methods.

Children aged 8-18 yr were asked to quantify their anxiety trait using the readily available faces scale and to respond to the trait component of the State-Trait Anxiety Inventory (STAI) for children (C) or adults (A) before the anaesthesia consultation. Using receiver operating characteristics analysis, we determined the faces scale optimal value on a construct cohort. A validation cohort was recruited to assess the accuracy of the results.

Results.

The construction cohort comprised 207 patients and the validation cohort 91 patients. The receiver operating characteristics analysis found an area under the curve of 0.75 [95% confidence interval (CI) 0.67, 0.83]. The optimal value for faces scale score was 4, with a sensitivity of 0.61 [95% CI 0.59, 0.62] and a specificity of 0.82 [95% CI 0.81, 0.83]. When this threshold was applied to the construction and validation cohorts, 61.3 and 44.4% of positives were true positives in the construction and validation cohorts, respectively; and 82.1 and 81.3% of negatives were true negatives, respectively.

Conclusions.

Our study determined the performance of a simple faces scale to measure the preoperative anxiety trait in children aged 8-18 yr. This tool is potentially helpful for clinicians aiming to identify patients at risk of preoperative anxiety and to assign them to targeted management.

The "E" word: epilepsy and perceptions of unfair treatment from the 2010 Australian Epilepsy Longitudinal Survey

AIM

The aim of the current study was to examine self-report data on perceptions of unfair treatment due to epilepsy.

METHOD

We analyzed data from the 2010 Australian Epilepsy Longitudinal Survey, distributed to 621 registrants on the Australian Epilepsy Research Register. A total of 343 responses were received (55% response rate), providing insight into experiences of life with epilepsy in Australia. Responses relating to perceptions of unfair treatment in areas of employment, education and community participation as a result of epilepsy are reported in this article.

RESULTS

Forty-eight percent of respondents reported perceptions of unfair treatment as a result of their epilepsy, with most providing details of their experiences. Discrimination in the workplace remains of key concern, with 47% citing examples of unfair treatment in this setting.

CONCLUSIONS

In spite of Australian anti-discrimination laws, findings indicate that full-time employment rates for people with epilepsy are lower than previously reported, with further mechanisms for support required to improve education and reduce experiences of stigma.

SU-E-T-107: Uncertainty Estimate of a Practical EBT-2 Film Dosimetry Approach: Transpose-And-Scan Technique

PURPOSE

To estimate the uncertainty of a practical EBT2 film dosimetry approach that has been established at our institution and used for routine patient-specific plan verifications, particularly for SBRT and RapidArc, as well as planning system commissioning. Our technique is unique from other common dosimetry protocols with respect to calibration, irradiation and scanning.

METHODS

Film dosimetry for patient-specific quality assurance of 29 patient plans were retrospectively reviewed. For each case, four films were irradiated; two for calibration and two for treatment plan. Each pair of two films were irradiated together in a phantom with one film transposed (rotated 180 degrees relative to the other) to compensate for asymmetric film response. After a minimum of 12 hrs post-irradiation, each film was scanned in four different orientations to mitigate non-uniform response of the scanner light and detector elements. The scanned 8 calibration and 8 plan images were averaged into one calibration and one plan film image, respectively. Each color channel of the calibration film was correlated to the reference dose matrix to produce a 3rd order polynomial calibration curve. Finally, each color channel of the plan film was converted to a dose map using the corresponding calibration curve. Average dose maps of the red and green channels were correlated to the treatment planning dose matrix, and the mean dose differences at the center of dose distributions (5×5mm̂2 area) as well as a gamma analysis were evaluated.

RESULTS

The absolute dose differences were -0.8±1.7% (range=-4.5-3.0%). The gamma pass-rates (3%/3mm) were 94±7% (min.=74%). The pass rate increased to 99±3%(min.=87%) with the film scaled relatively to the plan doses.

CONCLUSIONS

Based on a large number of cases, our approach appears to be robust to non-uniform film and scanner responses, and is shown to have an uncertainty (1SD) of less than 2% for absolute film dosimetry.

Gastric emptying of a liquid nutrient meal in the critically ill: relationship between scintigraphic and carbon breath test measurement

OBJECTIVE

It is assumed that delayed gastric emptying (GE) occurs frequently in critical illness; however, the prevalence of slow GE has not previously been assessed using scintigraphy. Furthermore, breath tests could potentially provide a convenient method of quantifying GE, but have not been validated in this setting. The aims of this study were to (i) determine the prevalence of delayed GE in unselected, critically ill patients and (ii) evaluate the relationships between GE as measured by scintigraphy and carbon breath test.

DESIGN

Prospective observational study.

SETTING

Mixed medical/surgical intensive care unit.

PATIENTS

25 unselected, mechanically ventilated patients (age 66 years (49-72); and 14 healthy subjects (age 62 years (19-84)).

INTERVENTIONS

GE was measured using scintigraphy and (14)C-breath test. A test meal of 100 ml Ensure (standard liquid feed) labelled with (14)C octanoic acid and (99m)Technetium sulphur colloid was placed in the stomach via a nasogastric tube.

MAIN OUTCOME MEASURES

Gastric 'meal' retention (scintigraphy) at 60, 120, 180 and 240 min, breath test t(50) (BTt(50)), and GE coefficient were determined.

RESULTS

Of the 24 patients with scintigraphic data, GE was delayed at 120 min in 12 (50%). Breath tests correlated well with scintigraphy in both patients and healthy subjects (% retention at 120 min vs BTt(50); r(2)=0.57 healthy; r(2)=0.56 patients; p≤0.002 for both).

CONCLUSIONS

GE of liquid nutrient is delayed in approximately 50% of critically ill patients. Breath tests correlate well with scintigraphy and are a valid method of GE measurement in this group.

The relation between forearm and vertebral mineral density and fractures in postmenopausal women

Vertebral and forearm mineral density (VMD and FMD, respectively) were determined in 124 postmenopausal women with no crushed vertebrae or peripheral fractures, 51 who had sustained peripheral fractures only since the menopause, 62 with vertebral compression(s) only and 75 with both types of fracture. There was a very significant correlation between the two measurements in the whole set. The scatter could not be accounted for by methodological error but was partly accounted for by body weight, since VMD was related to body weight and FMD was not. Whatever criterion was used for the diagnosis of osteoporosis (whether fracture or density) the percentage of misclassified cases was very similar by the two methods. However, VMD was relatively more reduced than FMD in vertebral fracture cases and FMD was marginally more reduced than VMD in peripheral fracture cases. There is little to choose between vertebral and forearm density in the diagnosis of osteoporosis but vertebral densitometry is slightly superior to forearm densitometry in describing the severity of osteoporosis in vertebral fracture patients.