Using second harmonic generation to predict patient outcome in solid tumors

BACKGROUND

Over-treatment of estrogen receptor positive (ER+), lymph node-negative (LNN) breast cancer patients with chemotherapy is a pressing clinical problem that can be addressed by improving techniques to predict tumor metastatic potential. Here we demonstrate that analysis of second harmonic generation (SHG) emission direction in primary tumor biopsies can provide prognostic information about the metastatic outcome of ER+, LNN breast cancer, as well as stage 1 colorectal adenocarcinoma.

METHODS

SHG is an optical signal produced by fibrillar collagen. The ratio of the forward-to-backward emitted SHG signals (F/B) is sensitive to changes in structure of individual collagen fibers. F/B from excised primary tumor tissue was measured in a retrospective study of LNN breast cancer patients who had received no adjuvant systemic therapy and related to metastasis-free survival (MFS) and overall survival (OS) rates. In addition, F/B was studied for its association with the length of progression-free survival (PFS) in a subgroup of ER+ patients who received tamoxifen as first-line treatment for recurrent disease, and for its relation with OS in stage I colorectal and stage 1 lung adenocarcinoma patients.

RESULTS

In 125 ER+, but not in 96 ER-negative (ER-), LNN breast cancer patients an increased F/B was significantly associated with a favorable MFS and OS (log rank trend for MFS: p = 0.004 and for OS: p = 0.03). On the other hand, an increased F/B was associated with shorter PFS in 60 ER+ recurrent breast cancer patients treated with tamoxifen (log rank trend p = 0.02). In stage I colorectal adenocarcinoma, an increased F/B was significantly related to poor OS (log rank trend p = 0.03), however this relationship was not statistically significant in stage I lung adenocarcinoma.

CONCLUSION

Within ER+, LNN breast cancer specimens the F/B can stratify patients based upon their potential for tumor aggressiveness. This offers a "matrix-focused" method to predict metastatic outcome that is complementary to genomic "cell-focused" methods. In combination, this and other methods may contribute to improved metastatic prediction, and hence may help to reduce patient over-treatment.

Determination of the separation efficiencies of a single-stage cryogenic distillation setup to remove krypton out of xenon by using a (83m)Kr tracer method

The separation of krypton and xenon is of particular importance for the field of direct dark matter search with liquid xenon detectors. The intrinsic contamination of the xenon with radioactive (85)Kr makes a significant background for these kinds of low count-rate experiments and has to be removed beforehand. This can be achieved by cryogenic distillation, a technique widely used in industry, using the different vapor pressures of krypton and xenon. In this paper, we present an investigation on the separation performance of a single stage distillation system using a radioactive (83m)Kr-tracer method. The separation characteristics under different operation conditions are determined for very low concentrations of krypton in xenon at the level of (83m)Kr/Xe = 1.9 ⋅ 10(-15), demonstrating, that cryogenic distillation in this regime is working. The observed separation is in agreement with the expectation from the different volatilities of krypton and xenon. This cryogenic distillation station is the first step on the way to a multi-stage cryogenic distillation column for the next generation of direct dark matter experiment XENON1T.

Pseudomonas exit-site infection: treatment outcomes with topical gentamicin in addition to systemic antibiotics

Background

Although, Pseudomonas exit-site infection (ESI) is recognized as a major complication of peritoneal dialysis (PD) with high risk of catheter loss due to refractory/recurrent infection or peritonitis, there is remarkably little literature about treatment outcomes. International Society for Peritoneal Dialysis guidelines advise the use of one to two antibiotics; in addition, we change standard exit-site care by stopping prophylactic mupirocin and starting regular use of gentamicin 1% cream.

Methods

Retrospective review of outcomes of Pseudomonas ESI from January 2012 to March 2015.

Results

During the study period, a total of 135 patients were on PD with an overall incidence of any ESI of 0.36/patient-year. There were 14 patients with ESI episodes with Pseudomonas with a rate of 0.12/patient-year. In total, 13 of 14 patients with ESI episodes were treated with oral ciprofloxacin and/or intraperitoneal (IP) gentamicin or ceftazidime, plus topical gentamicin, with a success rate of 38% (5/13). One patient had gentamicin-resistant Pseudomonas species and was treated successfully with topical polymyxin/bacitracin cream. Median follow-up time in cured patients was 385 days (range 74–1107). Six patients had associated with Pseudomonas peritonitis, four during follow-up and two at initial presentation. Three patients had recurrent ESI with Pseudomonas, with one successfully re-treated with topical and IP gentamicin. In total, in only 50% of the patients was Pseudomonas ESI successfully treated. Five of the patients (36%) changed modality to permanent haemodialysis following catheter removal.

Conclusion

Eradication of Pseudomonas ESI remains difficult even with the addition of topical gentamicin to the exit site. There should be a low threshold for catheter replacement.

Search for Event Rate Modulation in XENON100 Electronic Recoil Data

We have searched for periodic variations of the electronic recoil event rate in the (2-6) keV energy range recorded between February 2011 and March 2012 with the XENON100 detector, adding up to 224.6 live days in total. Following a detailed study to establish the stability of the detector and its background contributions during this run, we performed an unbinned profile likelihood analysis to identify any periodicity up to 500 days. We find a global significance of less than 1σ for all periods, suggesting no statistically significant modulation in the data. While the local significance for an annual modulation is 2.8σ, the analysis of a multiple-scatter control sample and the phase of the modulation disfavor a dark matter interpretation. The DAMA/LIBRA annual modulation interpreted as a dark matter signature with axial-vector coupling of weakly interacting massive particles to electrons is excluded at 4.8σ.

Vaccination against tuberculosis in badgers and cattle: an overview of the challenges, developments and current research priorities in Great Britain

Bovine tuberculosis (TB) is a significant threat to the cattle industry in England and Wales. It is widely acknowledged that a combination of measures targeting both cattle and wildlife will be required to eradicate bovine TB or reduce its prevalence until European official freedom status is achieved. Vaccination of cattle and/or badgers could contribute to bovine TB control in Great Britain, although there are significant gaps in our knowledge regarding the impact that vaccination would actually have on bovine TB incidence. Laboratory studies have demonstrated that vaccination with BCG can reduce the progression and severity of TB in both badgers and cattle. This is encouraging in terms of the prospect of a sustained vaccination programme achieving reductions in disease prevalence; however, developing vaccines for tackling the problem of bovine TB is challenging, time-consuming and resource-intensive, as this review article sets out to explain.

Tackling medication non-adherence in severe mental illness: where are we going wrong?

Although people with schizophrenia require medication to manage symptoms such as hearing voices, most do not take it as prescribed (they are non-adherent). We talked to psychiatrists, nurses and pharmacists about how they work with patients to help them be better at sticking with their medication. Although the professionals that we talked to recognized that treatment adherence was a major issue in their clinical work, they did not make best use of evidence-based interventions to address the problem. Often their practice was based on what they believed would work (e.g. patient education) even when the research shows that way of working to be ineffective. As far as we can determine, this is the first study to examine what interventions different mental health professionals report that they use in clinical practice to address patient's medication non-adherence. Non-adherence with medication is common in patients with schizophrenia. Addressing adherence to treatment may enhance clinical outcomes. Our aim was to explore mental health professionals experience and practise managing medication adherence in patients with schizophrenia. In this qualitative study, we interviewed mental health professionals from three key groups involved in promoting adherence: pharmacists, psychiatrists and nurses. Interviews were transcribed and analysed using a thematic approach. Thirty-five health professionals participated. From these interviews, we identified five main themes: my beliefs inform my practice; withholding information; adherence is important; who is responsible for promoting adherence?; and is it ok to pay people to take medication? Our overarching meta-theme was that practice with regard to promoting adherence was informed by beliefs and not by evidence. To the best of our knowledge, this is the first study to explore different mental health professionals' approaches to working with patients who do not want to take medication. The significance of participants' personal beliefs is an important observation. Our findings suggest that to support clinicians to more effectively help patients manage their medication, it may be first necessary to challenge pre-existing beliefs about adherence.

SURVEY OF STAFF OPINIONS ABOUT EXTENDED HAEMODIALYSIS TREATMENT TIME AND SERVICE IMPLICATIONS

BACKGROUND

We explored the potential impact of staff opinions and service provision upon patient's willingness to recruit to a clinical trial studying the effects of extended treatment time (TT) on haemodialysis (HD), six hours versus four hours for a period of twenty-four weeks.

METHODS

We conducted a local survey of dialysis nurses and a national survey of multidisciplinary HD staff opinions to extended TT including clinical benefits, tolerance to, prescription and ability to accommodate extended TT on in-centre HD programmes.

RESULTS

The survey was completed by 56/134 (42%) local nurses and the national survey by 15/72 (21%) of dialysis providers across the UK (35% nurses and 75% other healthcare professionals). The majority of respondents felt extended TT was clinically beneficial but only 42% of nurses would recommend extended TT compared to 95% of non-nursing healthcare professionals (p < 0.0001). Although 45% of nurses felt that it was well tolerated, non-nursing healthcare professionals suggested this was significantly higher at 75% (p < 0.05). The negative impact on service provision was agreed by 83% of nurses with the need to facilitate shifts within a finite time period and pressure to find session spaces being cited.

CONCLUSION

There is conflict between the understanding that extended TT is clinically beneficial and its prescription & delivery to patients. Enrolment to studies examining HD delivery strategies may be influenced by service provision and staff attitudes. In centre HD has been designed to maximise patient throughput and we may need to consider more flexible settings in which to deliver longer treatment time: Home HD maybe a solution.

Predictive value of interferon-gamma release assays for postpartum active tuberculosis in HIV-1-infected women

BACKGROUND

Data on the prognostic utility of interferon-gamma release assays (IGRAs) for active tuberculosis (TB) among human immunodeficiency virus 1 (HIV-1) infected individuals are limited.

METHODS

Samples from a perinatal cohort of HIV-1-infected women in Kenya, obtained during pregnancy, were tested using T-SPOT®.TB IGRAs to detect Mycobacterium tuberculosis-specific interferon-gamma (IFN-γ) responses. IFN-γ (cut-off values of >0, ≥6 and ≥10 spot-forming cells [SFC]/well) and CD4 cell count (cut-off values of <250 and <350 cells/l) were evaluated to determine sensitivity and specificity using a time-dependent receiver operating characteristic curve and positive predictive value (PPV) using the Kaplan Meier method for future TB within 1 year postpartum.

RESULTS

Of 327 women, 9 developed TB within 1 year postpartum (incidence rate 3.5/100 person-years of follow-up, 95%CI 1.66.7). IFN-γ ≥ 6 SFC/well was associated with an optimal trade-off between sensitivity (78%) and specificity (55%) and a PPV of 5.9%. In women with CD4 cell count of <250 cells/μl, the sensitivity and specificity of IFN- 6 SFC/well were respectively 89% and 63%, and the PPV was 19.2%.

CONCLUSION

Among HIV-1 infected women, IFN-γ response (≥6 SFC/well) during pregnancy lacked a high PPV for postpartum TB, but had higher sensitivity and PPV among immunosuppressed women (CD4 cell count of <250 cells/μl).

Impact of hernias on peritoneal dialysis technique survival and residual renal function

OBJECTIVE

We evaluated the effect of hernias and their surgical or conservative management on peritoneal dialysis (PD) technique survival and residual renal function.

METHODS

This 10-year single-center retrospective case-control study (January 2001 - January 2011) compared patient survival, PD technique survival, and residual renal function in patients with a history of abdominal hernias and in a control cohort matched for age and PD vintage.

RESULTS

Of 73 hernias identified in 63 patients (mean age: 55 years; 63% men), umbilical hernias were the most frequent (40%), followed by inguinal (33%), incisional, and epigastric hernias. Some hernias were surgically repaired before (n = 10) or at the time of PD catheter insertion (n = 11), but most (71%) were diagnosed and managed after initiation of PD. Overall, 49 of 73 (67%) hernias were treated surgically. In 53% of subjects, early postoperative dialysis was not needed; only 7 patients required temporary hemodialysis. The occurrence of a hernia and its treatment did not significantly affect residual renal function. After a hernia diagnosis or repair, 86% of patients were able to continue with PD. ♢

CONCLUSIONS

The incidence of abdominal hernia and hernia management in patients on PD do not significantly influence residual renal function or PD technique survival. Timely management of hernias is advisable and does not preclude continuation with PD as a dialysis modality.

BRAF mutation testing algorithm for vemurafenib treatment in melanoma: recommendations from an expert panel

The incidence of melanoma has increased rapidly over the past 30 years, and the disease is now the sixth most common cancer among men and women in the U.K. Many patients are diagnosed with or develop metastatic disease, and survival is substantially reduced in these patients. Mutations in the BRAF gene have been identified as key drivers of melanoma cells and are found in around 50% of cutaneous melanomas. Vemurafenib (Zelboraf(®) ; Roche Molecular Systems Inc., Pleasanton, CA, U.S.A.) is the first licensed inhibitor of mutated BRAF, and offers a new first-line option for patients with unresectable or metastatic melanoma who harbour BRAF mutations. Vemurafenib was developed in conjunction with a companion diagnostic, the cobas(®) 4800 BRAF V600 Mutation Test. The purpose of this paper is to make evidence-based recommendations to facilitate the implementation of BRAF mutation testing and targeted therapy in patients with metastatic melanoma in the U.K. The recommendations are the result of a meeting of an expert panel and have been reviewed by melanoma specialists and representatives of the National Cancer Research Network Clinical Study Group on behalf of the wider melanoma community. This article is intended to be a starting point for practical advice and recommendations, which will no doubt be updated as we gain further experience in personalizing therapy for patients with melanoma.

The role of peritoneal dialysis in modern renal replacement therapy

Most patients starting dialysis can choose between peritoneal dialysis and haemodialysis. There is little evidence proving that one form of dialysis is better than the other; although there may be an early advantage to peritoneal dialysis (PD) in young patients with residual function this effect is short-lived. Technique failure develops after years on PD so dialysis modality will often change during a long dialysis career. Quality of life studies, which must be interpreted carefully, indicate that patients require information about the impact of dialysis on their lifestyle as well as health-related outcomes so that they can choose the most suitable dialysis modality. Increasing numbers of frail elderly patients are starting dialysis; support in the home by nursing staff may facilitate the use of PD in this group. In the UK guidelines prioritise the patient's choice of dialysis modality (where feasible) based on good quality predialysis education. Cost of treatment is generally lower on PD, which is particularly recommended for patients with residual renal function and few comorbidities.

Limits on spin-dependent WIMP-nucleon cross sections from 225 live days of XENON100 data

We present new experimental constraints on the elastic, spin-dependent WIMP-nucleon cross section using recent data from the XENON100 experiment, operated in the Laboratori Nazionali del Gran Sasso in Italy. An analysis of 224.6 live days×34 kg of exposure acquired during 2011 and 2012 revealed no excess signal due to axial-vector WIMP interactions with 129Xe and 131Xe nuclei. This leads to the most stringent upper limits on WIMP-neutron cross sections for WIMP masses above 6 GeV/c², with a minimum cross section of 3.5×10(-40) cm² at a WIMP mass of 45 GeV/c², at 90% confidence level.