The therapeutic investigation

No abstract available.

Becoming the illness

“What you think, you become” – Buddha

Experimental evidence for hillslope control of landscape scale

Landscape evolution theory suggests that climate sets the scale of landscape dissection by modulating the competition between diffusive processes that sculpt convex hillslopes and advective processes that carve concave valleys. However, the link between the relative dominance of hillslope and valley transport processes and landscape scale is difficult to demonstrate in natural landscapes due to the episodic nature of erosion. Here, we report results from laboratory experiments combining diffusive and advective processes in an eroding landscape. We demonstrate that rainsplash-driven disturbances in our experiments are a robust proxy for hillslope transport, such that increasing hillslope transport efficiency decreases drainage density. Our experimental results demonstrate how the coupling of climate-driven hillslope- and valley-forming processes, such as bioturbation and runoff, dictates the scale of eroding landscapes.

Non-obtrusive sources and secondary actors

No abstract available.

Availability of highly sensitive troponin assays and acute coronary syndrome care: insights from the SNAPSHOT registry

OBJECTIVES

To examine differences in care and inhospital course of patients with possible acute coronary syndrome (ACS) in Australia and New Zealand based on whether a highly sensitive (hs) troponin assay was used at the hospital to which they presented.

DESIGN, SETTING AND PATIENTS

A snapshot study of consecutive patients presenting to hospitals in Australia and New Zealand from 14 to 27 May 2012 with possible ACS.

MAIN OUTCOME MEASURES

Rates of major adverse cardiac events (inhospital death, new or recurrent myocardial infarction, stroke, cardiac arrest or worsening heart failure); association between assay type and outcome (via propensity score matching and a generalised estimating equation [GEE]; averages of the predicted outcomes among patients who were treated with and without the availability of an hs assay (via inverse probability-weighting [IPW] with regression-adjusted estimators).

RESULTS

4371 patients with possible ACS were admitted to 283 hospitals. Over half of the hospitals (156 [55%]) reported using the hs assay and most patients (2624 [60%]) had hs tests (P = 0.004). Use of the hs assay was independent of hospital coronary revascularisation capability. Patients tested with the hs assay had more non-invasive investigations (exercise tests, stress echocardiography, stress nuclear scans, and computed tomography coronary angiography) than those tested with the sensitive assay. However, there were no differences between the groups in rates of angiography or revascularisation. All adjusted analyses showed a consistently lower rate of inhospital events, including recurrent heart failure in patients for whom the hs assay was used (GEE odds ratio, 0.75; 95% CI, 0.60-0.94; P = 0.014); IPW analysis showed a 2.3% absolute reduction in these events with the use of the hs assay (P = 0.018).

CONCLUSION

Use of hs troponin testing of patients hospitalised with possible ACS was associated with an increased rate of non-invasive cardiac investigations and fewer inhospital adverse events.

The prepared patient

No abstract available.

Benefit to neoadjuvant anti-human epidermal growth factor receptor 2 (HER2)-targeted therapies in HER2-positive primary breast cancer is independent of phosphatase and tensin homolog deleted from chromosome 10 (PTEN) status

BACKGROUND

Assessment of phosphatase and tensin homolog deleted from chromosome 10 (PTEN) might be an important tool in identifying human epidermal growth factor receptor 2 (HER2)-positive breast cancer patients unlikely to derive benefit from anti-HER2 therapies. However, studies to date have failed to demonstrate its predictive role in any treatment setting.

PATIENTS AND METHODS

Prospectively collected baseline core biopsies from 429 early-stage HER2-positive breast cancer patients treated with trastuzumab, lapatinib, or their combination in the Neo-ALTTO study were stained using two anti-PTEN monoclonal antibodies (CST and DAKO). The association of PTEN status and PI3K pathway activation (defined as either PTEN loss and/or PIK3CA mutation) with total pathological complete response (tpCR) at surgery, event-free survival (EFS), and overall survival (OS) was evaluated.

RESULTS

PTEN loss was observed in 27% and 29% of patients (all arms, n = 361 and n = 363) for CST and DAKO, respectively. PTEN loss was more frequently observed in hormone receptor (HR)-negative (33% and 36% with CST and DAKO, respectively) compared with HR-positive tumours (20% and 22% with CST and DAKO, respectively). No significant differences in tpCR rates were observed according to PTEN status. PI3K pathway activation was found in 47% and 48% of patients (all arms, n = 302 and n = 301) for CST and DAKO, respectively. Similarly, tpCR rates were not significantly different for those with or without PI3K pathway activation. Neither PTEN status nor PI3K pathway activation were predictive of tpCR, EFS, or OS, independently of treatment arm or HR status. High inter-antibody and inter-observer agreements were found (>90%). Modification of scoring variables significantly affected the correlation between PTEN and HR status but not with tpCR.

CONCLUSION

These data show that PTEN status determination is not a useful biomarker to predict resistance to trastuzumab and lapatinib-based therapies. The lack of standardization of PTEN status determination may influence correlations between expression and relevant clinical end points.

CLINICAL TRIALS

This trial is registered with ClinicalTrials.gov: NCT00553358.

Retrospective evaluation of continuation rates following a switch to subcutaneous methotrexate in rheumatoid arthritis patients failing to respond to or tolerate oral methotrexate: the MENTOR study

OBJECTIVES

To retrospectively evaluate continuation rates in patients with rheumatoid arthritis (RA) who failed to respond to or tolerate oral methotrexate (MTX) and were subsequently switched to subcutaneous MTX (SC MTX) in routine clinical practice.

METHOD

We conducted a retrospective review of all patients with RA who had been prescribed SC MTX following oral MTX at the Norfolk and Norwich University Hospital and had been captured on the hospital pharmacy database of MTX use between 17 May 2011 and 20 March 2012. Only patients for whom complete records were available before and for at least 6 months after the switch were included.

RESULTS

A total of 196 patients were included in the analysis (75.5% women; mean age at diagnosis 47.4 years; mean duration of oral MTX therapy 6.6 years). Patients were changed from oral to SC MTX because of lack of efficacy (50.5%), adverse events (43.9%), or other/unknown reasons (5.6%). High continuation rates were seen, with 83.0% of patients analysed still on SC MTX at 1 year, 75.2% at 2 years, and 47.0% at 5 years. Following the switch to SC MTX, < 10% of patients were prescribed additional biologic therapy during the first and second year because of an insufficient response.

CONCLUSIONS

Treatment with SC MTX results in high continuation rates in patients who fail to respond to or tolerate oral MTX. Consequently, management guidelines should be adapted to include advice that SC MTX should be used before biologic therapy and that MTX failure is defined as failure only when use of SC MTX has failed.

Feasibility and acceptability of HIV screening through the use of rapid tests by general practitioners in a Brussels area with a substantial African community

OBJECTIVES

To assess:1) if HIV screening with rapid tests in neighbourhoods with a substantial African community is feasible and acceptable among GPs and patients; 2) HIV seroprevalence.

METHODS

Multicenter prospective study with 10 trained physicians. Use of HIV standard test and INSTI Ultrarapid test.

INCLUSION CRITERIA

MSM, sex worker, multiple sexual partners, having returned or coming from a country with high HIV prevalence, IVDU, Indicator conditions as defined by HIV Indicator Diseases across Europe Study, having an AIDS-defining illness, having had a recent pregnancy or abortion; or presenting other risks.

RESULTS

From August 2010 to August 2011, 10 trained GPs offered an HIV test to 224 patients: 51% ♀, 48% ♂, 43% Caucasians, 45% Africans.

INCLUSION CRITERIA

32% "high risk group", 9% returning from an endemic country, 29% with an indicator condition; 12 patients (6%) refused the standard test. The INSTI was offered to 217(97%), 197 performed with 2 reactive rapid tests confirmed. The seroprevalence according to ethnic origin was 0% among Caucasians and 2.2% among Africans and was 1.5% among patients with an indicator condition. 1087 consecutive consultations of the same GPs were recorded: 42% patients had ≥ 1 inclusion criteria among which 41% of offered tests, that is to say 59% of "missed opportunities". The reasons for not offering the test as recorded for 55% of patients:"not indicated" 44.5%, "no time" 33%, "impossible to propose" 15%, test completed previously 11%, known HIV-positive 4%.

CONCLUSIONS

Standard and rapid tests are well received by patients but were usually not offered by doctors who have been trained.

Genetic polymorphism rs6922269 in the MTHFD1L gene is associated with survival and baseline active vitamin B12 levels in post-acute coronary syndromes patients

Background and Aims

The methylene-tetrahydrofolate dehydrogenase (NADP+ dependent) 1-like (MTHFD1L) gene is involved in mitochondrial tetrahydrofolate metabolism. Polymorphisms in MTHFD1L, including rs6922269, have been implicated in risk for coronary artery disease (CAD). We investigated the association between rs6922269 and known metabolic risk factors and survival in two independent cohorts of coronary heart disease patients.

Methods and Results

DNA and plasma from 1940 patients with acute coronary syndromes were collected a median of 32 days after index hospital admission (Coronary Disease Cohort Study, CDCS). Samples from a validation cohort of 842 patients post-myocardial infarction (PMI) were taken 24–96 hours after hospitalization. DNA samples were genotyped for rs6922269, using a TaqMan assay. Homocysteine and active vitamin B12 were measured by immunoassay in baseline CDCS plasma samples, but not PMI plasma. All cause mortality was documented over follow-up of 4.1 (CDCS) and 8.8 (PMI) years, respectively. rs6922269 genotype frequencies were AA n = 135, 7.0%; GA n = 785, 40.5% and GG n = 1020, 52.5% in the CDCS and similar in the PMI cohort. CDCS patients with AA genotype for rs6922269 had lower levels of co-variate adjusted baseline plasma active vitamin B12 (p = 0.017) and poorer survival than patients with GG or GA genotype (mortality: AA 19.6%, GA 12.0%, GG 11.6%; p = 0.007). In multivariate analysis, rs6922269 genotype predicted survival, independent of established covariate predictors (p = 0.03). However the association between genotype and survival was not validated in the PMI cohort.

Conclusion

MTHFD1L rs6922269 genotype is associated with active vitamin B12 levels at baseline and may be a marker of prognostic risk in patients with established coronary heart disease.

Concomitant myasthenia gravis and macroprolactinoma: the immunomodulatory role of prolactin and its potential therapeutic use

Considerable evidence attests to the role of the hypothalamic-pituitary endocrine axis (HPA) in the maintenance of normal immunocompetence. The immune and neuroendocrine systems are integrally linked and coordinated with bidirectional communication maintaining immune balance. Any disturbance of the normal function of the HPA may significantly alter native immunocompetence and therefore be associated with the development of disorders which have a clearly established autoimmune basis. Molecular and functional evidence shows prolactin, produced by the anterior pituitary, to be a cytokine, exerting its effect via both paracrine and endocrine mechanisms [1]. Its involvement in the activation of multiple immune responses may adversely upregulate certain autoimmune diseases. Myasthenia gravis (MG) has long been recognized as an autoimmune disorder. In this mini review, we present the coterminous presentation of MG and prolactin-secreting macroadenoma. We review published cases in the world literature, discuss pathological mechanism, and consider future targeted therapies.