Characterising private and shared signatures of positive selection in 37 Asian populations

The Asian Diversity Project (ADP) assembled 37 cosmopolitan and ethnic minority populations in Asia that have been densely genotyped across over half a million markers to study patterns of genetic diversity and positive natural selection. We performed population structure analyses of the ADP populations and divided these populations into four major groups based on their genographic information. By applying a highly sensitive algorithm haploPS to locate genomic signatures of positive selection, 140 distinct genomic regions exhibiting evidence of positive selection in at least one population were identified. We examined the extent of signal sharing for regions that were selected in multiple populations and observed that populations clustered in a similar fashion to that of how the ancestry clades were phylogenetically defined. In particular, populations predominantly located in South Asia underwent considerably different adaptation as compared with populations from the other geographical regions. Signatures of positive selection present in multiple geographical regions were predicted to be older and have emerged prior to the separation of the populations in the different regions. In contrast, selection signals present in a single population group tended to be of lower frequencies and thus can be attributed to recent evolutionary events.

Permissive expansion and homing of adoptively transferred T cells in tumor-bearing hosts

Activated T cells expressing endogenous or transduced TCRs are two cell types currently used in clinical adoptive T-cell therapy. The ability of these cells to recognize their antigen, expand and traffic to the tumor site are the initial steps necessary for successful therapy. In this study, we used in vivo bioluminescent imaging (BLI) of Renilla luciferase (RLuc) expressing T cells to evaluate the ability of adoptively transferred T cells to survive, expand and home to tumor site in vivo. Using this method, termed RT-Rack (Rluc T cell tracking), we followed T-cell response against tumors in vivo. Expansion and homing of adoptively transferred T cells were antigen dependent, but independent of the host immune status. Moreover, we successfully detected T-cell response to small and large tumors, including autochthonous liver tumors. The adoptively transferred T cells were not ignorant or excluded in a partially tolerant host, which expressed low level of the target in the periphery. Using T cell receptor (TCR)-engineered T cells, we showed the ability of these cells to respond in tumor-bearing hosts by expanding and homing to the tumor site. In all these models, the host immune status, the nature of the tumor or of the antigen, the tumor size and the presence of the targeted antigen in the periphery did not prevent the adoptively transferred T cells from responding by expanding and homing to the tumor. However, T cells had higher expression of the inhibitory receptor PD1 and reduced functional activity when a self-antigen was targeted.

Portkatheterbrüche bei 361 implantierten Portsystemen Ursachenanalyse – Lösungsmöglichkeiten – Literaturübersicht

INTRODUCTION

The use of a venous port-catheter-system is known as a relatively safe implant. Besides infections, the breakage of PIPS is the most common reason for explanation before term. The purpose of this study is to analyse port-related complications and to show ways of preventing them.

METHOD

Between 1.1.1994 and 31.12.1999, 391 PIPS were implanted in the V. subclavia with the Seldinger technique at Surgical Clinic 1 of the University of Leipzig. Subsequently, 311 of them were followed up until 31.12.2000, with a mean observation time of 45 months.

RESULTS

We registered 48 complications altogether (15.4% of 311), 21(6.7%) of which occurred immediately after implantation (up to 30 days postoperatively). These could be divided either into wound-healing disorders/pulmonary distress (4.5%, n = 14) or complications concerning the catheter systems (2.3%, n = 7). Long-term complications after 31 days were evident in 27 patients (8.7%), due either to infections (4.5%, n = 13) or catheter-associated problems (4.5%, n = 14). Catheter lesions occurred in nine cases (2.9% out of 311) at the point of entry into the musculus pectoralis, i.e., where the catheter had to change direction. Typically these were lengthways tears caused by the catheter. We observed one full breakage without dislocation, and two dislocated catheter fragments in the systemic circulation. We consider the change of direction to be responsible for wear on the silicon catheter. During implantation, extreme change of direction of the catheter should be avoided because this is where breakage happens. Catheter implantation by means of exposure of the vena basilica in the infraclavicular triangle is the method of choice.

Ultrasound elastography of pulmonary lesions - a feasibility study

INTRODUCTION

The potential of sonography in the examination of lung tissue is extremely limited by the air-filled alveoles of the lung. Only in special circumstances like pleural adhesion lesions, atelectasis or pneumonia can lung tissue be visualized by B-mode sonography. Real-time elastography was primarily applied to detect and visualize pulmonary lesions.

METHODS AND PATIENTS

8 patients with a total of 18 histologically proven metastases of the lung were included. All pulmonary lesions were detected by computed tomography. Sonographic examination was performed with a 7.5 MHz linear transducer (Acuson Antares premium edition, Siemens, Erlangen, Germany), including B-mode and real-time elastography (RTE). The mean distance between pleura and the lesions ranged from 0 to 2.5 cm. Two lesions were located in the upper right lobe, eleven lesions in the lower right and five in the lower left lobe.

RESULTS

RTE was able to detect and visualize all 18 pulmonary lesions in contrast to B-mode. The size and distance of the lesions from the pleura correlated with the CT findings.

CONCLUSION

In contrast to B-mode sonography, RTE is able to detect and visualize peripheral, non-pleural adherent pulmonary lesions.

Time evolution of luminescence of Sr₂SiO₄:Eu²⁺

In this contribution, the photoluminescence, time-resolved luminescence and luminescence kinetics of α'-Sr2SiO4:Eu(2+) are studied. The luminescence of Sr2SiO4:Eu(2+) consists of two broad bands, peaked at 490 nm (blue-green) and 570 nm (yellow-orange), which originate from two luminescence centers, related to Eu(2+) in ten-coordinated SI and nine-coordinated SII sites, respectively. Based on spectroscopic data the energetic structure of Sr2SiO4:Eu(2+) has been developed, which includes the bands edges, energies of Eu(2+) in the SI and SII sites and energies of strontium and oxygen vacancies. To investigate the long-lasting luminescence phenomenon in Sr2SiO4:Eu(2+) the temperature influence on the time evolution of luminescence was analyzed. It has been found that the long-lasting luminescence is related to the Eu(2+) in SII site. The shallowest traps responsible for emission decaying within a few seconds are tentatively attributed to the [Eu(3+)(SII)-[Formula: see text]] centers. The depth of traps responsible for the long-lasting luminescence observed at room temperature has been estimated as equal 0.73 eV.

Factors affecting delay in initiation of treatment of tuberculosis in the Thames Valley, UK

OBJECTIVE

To quantify and determine factors associated with delay in initiation of tuberculosis (TB) treatment in the Thames Valley area, South East England, and the proportion of this delay that could be attributed to patient care-seeking or to delay within the National Health Service (NHS).

STUDY DESIGN

Retrospective analysis study reviewing medical notes and enhanced TB surveillance data.

METHODS

Demographic and clinical information was collected from medical notes and the Enhanced TB Surveillance database for patients who were diagnosed with TB and resident in the Thames Valley. Treatment delay was defined as the period between the onset of symptoms and the start of treatment. Patient delay was defined as the period between the onset of symptoms and the first presentation to the NHS. Health service delay was defined as the period between the first contact with the NHS and the start of treatment. Univariate and multivariate linear regression analyses were used to assess the association between delays and explanatory variables (age, gender, place of birth, ethnicity, disease site, sputum smear, culture, primary care trust of residence).

RESULTS

The study included 273 patients with TB. The median time between symptom onset and initiation of treatment was 73 days [95% confidence interval (CI) 65-89], of which the contributions of health service, patient and referral delays were 39 (95% CI 34-55), 29 (95% CI 22-36) and 16 (95% CI 12-24) days, respectively. On multivariate analysis, extrapulmonary TB (P = 0.010), female (P = 0.003) and UK-born (P = 0.008) patients were associated with longer health service delay. Age (P = 0.001) and extrapulmonary TB (P = 0.010) were associated with longer overall treatment delay.

CONCLUSION

Treatment delay for TB, especially delay after first presentation to the NHS, remains a public health concern. Differences in health service delay, for example by gender and country of birth, highlight that some of this should be open to health service intervention.

Epidemiology of internal contamination with polonium-210 in the London incident, 2006

BACKGROUND

More than 700 UK residents were tested for possible contamination with polonium-210 ((210)Po) following the alleged poisoning of Mr Alexander Litvinenko in London in November 2006. This paper describes the epidemiology of internal contamination with the radionuclide in this group.

METHODS

11 locations in London had been identified as sufficiently environmentally contaminated with (210)Po to present a health risk to people associated with them. Public health consultant teams identified individuals at risk and offered 24-h urine testing for (210)Po excretion. Prevalence of internal contamination was estimated, and a retrospective cohort analysis was completed for each location.

RESULTS

Overall 139 individuals (prevalence 0.19 (95% CI 0.13 to 0.27)) showed evidence of internal contamination with (210)Po, although none with uptakes likely to cause adverse health effects. Substantial prevalence was seen among specific hotel service staff, customers, staff and other users of a hotel bar, office and hospital staff, staff of one restaurant and residents of and visitors to the family home. Increased risks of contamination were seen for a hotel bar in association with occupational, behavioural and temporal factors. Occupational and guest exposure to contaminated areas of hotels were also associated with increased contamination risk. Nurses were more likely to become contaminated than other staff involved in direct patient care.

CONCLUSIONS

Uptake of trace amounts of radionuclide in this incident was frequent. Occupational, behavioural and temporal gradients in contamination risk were mostly consistent with a priori site risk assessments. Utility of the investigation methods and findings for future accidental or deliberate environmental contamination incidents are discussed.

Effect of CT scan protocols on x-ray-induced DNA double-strand breaks in blood lymphocytes of patients undergoing coronary CT angiography

AIMS

To compare in vivo DNA lesions induced during helical and sequential coronary computed tomography angiography (CTA) and to evaluate the effect of CT parameters on double-strand break (DSB) levels.

METHODS

Thirty-six patients were examined with various CT protocols and modes (helical scan, n = 27; sequential scan, n = 9) either using a 64-slice dual-source or a 128-slice CT system. Blood samples were obtained before and 30 min after CT. Lymphocytes were isolated, stained against the phosphorylated histone variant γ-H2AX, and DSBs were visualised by using fluorescence microscopy.

RESULTS

DSB yields 30 min after CTA ranged from 0.04 to 0.71 per cell and showed a significant correlation to DLP (ρ = 0.81, p < 0.00001). Median DSB yield and median DLP were significantly lower after sequential compared to helical CT examinations (0.11 vs. 0.37 DSBs/cell and 249 vs. 958 mGy cm, p < 0.00001). Additional calcium scoring led to an increase in DLP (p = 0.15) and DSB levels (p = 0.04). DSB levels normalised to the DLP showed a significant correlation to the attenuation of the blood (ρ = 0.53, p = 0.01) and a negative correlation to the body mass index of the patients (ρ = -0.37, p = 0.06).

CONCLUSION

γ-H2AX immunofluorescence microscopy allows one to determine dose-related effects on x-ray-induced DSB levels and to consider individual factors which cannot be monitored by physical dose measurements.

Recent developments in stress urinary incontinence in women

This article provides an overview of stress urinary incontinence (SUI) and current treatments. The role of the specialist nurse is also explored. It is recommended that conservative treatment is offered to all women with SUI. This article was originally published in Nursing Standard in 2006, volume 20, number 35, pages 48-54.

Peripheral intravenous power injection of iodinated contrast media through 22G and 20G cannulas: can high flow rates be achieved safely? A clinical feasibility study

PURPOSE

Modern examination protocols for computed tomography (CT) often require high injection rates of iodinated contrast media (CM). The purpose of this study was to evaluate the maximum achievable flow rates and stability of different peripheral intravenous catheters (IVC) in vitro and to assess the feasibility of higher injection rates through small IVC in vivo.

MATERIALS AND METHODS

For in vitro experiments flow measurements followed by high pressure testing of different types of IVC (22, 20, and 18 gauge [G]) were performed. For the in vitro study 91 patients with already inserted 22 or 20G IVC who had been referred for CT received Iopamidol (300 mg iodine/ml) at flow rates between 2 and 5 ml/sec. Complications were documented.

RESULTS

The maximal achievable flow rate of the tested IVC in vitro ranged from 5 to 8 ml/sec. No damage was observed during in vitro testing. The initially targeted in vivo flow rate was dropped in 33 of 91 (36 %) patients because the IVC could not be flushed adequately with saline before CM injection. Extravasation of CM occurred in 2 cases. In the remaining 58 patients the standard CT protocol was performed with flow rates of 3 ml/sec through 22G IVC and 5 ml/sec through 20G IVC, respectively. In this group, the extravasation of CM was observed twice (p > 0.05).

CONCLUSION

Even with highly viscous CM, high flow rates can be applied in vitro in 22, 20, and 18G IVC without risking material damage. In vivo power injection of iodinated CM through 22G and 20G IVC seems to be safely achievable in the majority of patients with flow rates of up to 3 ml/sec and 5 ml/sec. Extravasation rates do not differ significantly between patients with high-flow or low-flow injections.

Unusual subcutaneous localisation of a dermatofibrosarcoma protuberans of the female breast: a case report

Dermatofibrosarcoma protuberans (DFSP) is a slow growing soft tissue neoplasm of dermal fibroblastic origin characterised by local invasion and a high propensity for local recurrence. We report a 31-year-old woman with subcutaneous DFSP of the breast, which is an unusual localisation. Diagnostic work-up comprised clinical examination, mammography and ultrasound. Definitive diagnosis was not possible prior to histological analysis of the lesion. Wide excision of the tumour was performed, which is the therapy of choice in DFSP. Ultrasound played an important role in histological diagnosis before definitive surgery and might be helpful in follow-up of patients with DFSP of the breast.

[Mammography screening]

Exclusive biannual mammography screening for women ages 50-69 years reduces the mortality from breast cancer among participants by 35%. Compared with 50% of clinically detected cancers, only 20% of carcinomas detected in screening have nodal metastases, and up to 55% of screening carcinomas are in the T1 stage of "minimal cancer." In many European countries (including Sweden, Norway, the Netherlands, and Great Britain), mammography screening programmes have been established for more than 10 years. In Germany, the aim is to establish, by 2008, a nationwide organised programme on the basis of the European Guidelines for Quality Assurance. This goal requires 80-100 mammography screening units. The first screening units went into use in 2005. Women between 50 and 69 years are invited to participate in 2-year intervals.

Clinical evaluation of bone-subtraction CT angiography (BSCTA) in head and neck imaging

Fifty-one patients were examined with bone subtraction CT angiography (BSCTA). Data were acquired on 4-and 64-slice spiral CT systems. The post-processing method is based on fully automatic registration of non-enhanced and contrast-enhanced CT data and subsequent selective bone removal. Vascular structures and brain tissue are retained with the original CTA noise level. Image quality and delineation of the pathologic process were assessed and artifacts introduced by the bone removal process recorded. The bone subtraction algorithm worked successfully in all examinations. The processing time was 6 min on average. Image quality was rated excellent in 20 (39%), good in 26 (51%) and acceptable in 5 (10%) patients. Ophthalmic arteries were visible in 12 (24%) patients bilaterally, in 13 (25%) patients unilaterally and in 26 (51%) patients at least at the origin. BSCTA improved visualization of the infraclinoid ICA and the vertebral arteries. The depiction of stenosis of the extracranial ICA and supraclinoid aneurysms was not significantly improved. In patients with suspicion of sinus thrombosis, BSCTA and conventional CTA yielded similar results. To conclude, BSCTA improves the visualization of vessels with close contact to bone and can improve the diagnostic accuracy and therapy planning of infraclinoid aneurysms.

CTA der A.�carotis mit unterschiedlichen CT-Ger�ten

Noninvasive modalities like CTA are increasingly replacing selective angiography in the evaluation of carotid artery stenosis. Dedicated scan protocols and contrast injection techniques are mandatory for the morphological assessment of carotid artery stenosis. These protocols need to be adapted to different scanner types. The delineation of plaque components and the residual lumen is improved with high resolution scan protocols and dedicated reconstruction algorithms. The exact delineation of in-stent stenosis remains limited. Standardization of postprocessing is crucial in order to attain reproducible results. Multislice spiral CT allows reliable grading of carotid artery stenosis. Relevant venous opacification and pulsation artifacts have to be expected with 4-slice scanners, the short scan time of the latest CT scanners minimize these problems.