Concordance of blood- and tumor-based detection of RAS mutations to guide anti-EGFR therapy in metastatic colorectal cancer

Background

Circulating tumor DNA (ctDNA) is a potential source for tumor genome analysis. We explored the concordance between the mutational status of RAS in tumor tissue and ctDNA in metastatic colorectal cancer (mCRC) patients to establish eligibility for anti-epidermal growth factor receptor (EGFR) therapy.

Patients and methods

A prospective-retrospective cohort study was carried out. Tumor tissue from 146 mCRC patients was tested for RAS status with standard of care (SoC) PCR techniques, and Digital PCR (BEAMing) was used both in plasma and tumor tissue.

Results

ctDNA BEAMing RAS testing showed 89.7% agreement with SoC (Kappa index 0.80; 95% CI 0.71 − 0.90) and BEAMing in tissue showed 90.9% agreement with SoC (Kappa index 0.83; 95% CI 0.74 − 0.92). Fifteen cases (10.3%) showed discordant tissue-plasma results. ctDNA analysis identified nine cases of low frequency RAS mutations that were not detected in tissue, possibly due to technical sensitivity or heterogeneity. In six cases, RAS mutations were not detected in plasma, potentially explained by low tumor burden or ctDNA shedding. Prediction of treatment benefit in patients receiving anti-EGFR plus irinotecan in second- or third-line was equivalent if tested with SoC PCR and ctDNA. Forty-eight percent of the patients showed mutant allele fractions in plasma below 1%.

Conclusions

Plasma RAS determination showed high overall agreement and captured a mCRC population responsive to anti-EGFR therapy with the same predictive level as SoC tissue testing. The feasibility and practicality of ctDNA analysis may translate into an alternative tool for anti-EGFR treatment selection.

Effects of TNF receptor blockade on in vitro cell survival and response to negative energy balance in dairy cattle

Background

Associative data and some controlled studies suggest that the inflammatory cytokine tumor necrosis factor (TNF) α can induce fatty liver in dairy cattle. However, research demonstrating that TNFα is a necessary component in the etiology of bovine fatty liver is lacking. The aim of this work was to evaluate whether blocking TNFα signaling with a synthetic cyclic peptide (TNF receptor loop peptide; TRLP) would improve liver metabolic function and reduce triglyceride accumulation during feed restriction.

Results

Capability of TRLP to inhibit TNFα signaling was confirmed on primary bovine hepatocytes treated with recombinant bovine TNFα and 4 doses of TRLP (0, 1, 10, 50 μmol/L) over 24 h. Next, 4 lactating Holstein cows (parity 1.4 ± 0.5, 433 ± 131 d in milk) in an incomplete Latin rectangle design (3 × 2) were subcutaneously administered with different TRLP doses (0, 1.5, 3.0 mg/kg BW) every 4 h for 24 h, followed by an intravenous injection of TNFα (5 μg/kg BW). Before and for 2 h after TNFα injection, TRLP decreased plasma non-esterified fatty acid (NEFA) concentration (P ≤ 0.05), suggesting an altered metabolic response to inflammation. Finally, 10 non-pregnant, non-lactating Holstein cows (3.9 ± 1.1 yr of age) were randomly assigned to treatments: control (carrier: 57% DMSO in PBS) or TRLP (1.75 mg TRLP /kg BW per day). Treatments were administrated every 4 h for 7 d by subcutaneous injection to feed-restricted cows fed 30% of maintenance energy requirements. Daily blood samples were analyzed for glucose, insulin, β-hydroxybutyrate, NEFA, and haptoglobin concentrations, with no treatment effects detected. On d 7, cows completed a glucose tolerance test (GTT) by i.v. administration of a dextrose bolus (300 mg glucose/kg BW). Glucose, insulin, and NEFA responses failed to demonstrate any significant effect of treatment during the GTT. However, plasma and liver analyses were not indicative of dramatic lipolysis or hepatic lipidosis, suggesting that the feed restriction protocol failed to induce the metabolic state of interest. Injection site inflammation, assessed by a scorer blinded to treatment, was enhanced by TRLP compared to control.

Conclusions

Although the TRLP inhibited bovine TNFα signaling and altered responses to i.v. administration of TNFα, repeated use over 7 d caused apparent local allergic responses and it failed to alter metabolism during a feed restriction-induced negative energy balance. Although responses to feed restriction seemed atypical in this study, side effects of TRLP argue against its future use as a tool for investigating the role of inflammation in metabolic impacts of negative energy balance.

An excess of massive stars in the local 30 Doradus starburst

The 30 Doradus star-forming region in the Large Magellanic Cloud is a nearby analog of large star-formation events in the distant universe. We determined the recent formation history and the initial mass function (IMF) of massive stars in 30 Doradus on the basis of spectroscopic observations of 247 stars more massive than 15 solar masses ([Formula: see text]). The main episode of massive star formation began about 8 million years (My) ago, and the star-formation rate seems to have declined in the last 1 My. The IMF is densely sampled up to 200 [Formula: see text] and contains 32 ± 12% more stars above 30 [Formula: see text] than predicted by a standard Salpeter IMF. In the mass range of 15 to 200 [Formula: see text], the IMF power-law exponent is [Formula: see text], shallower than the Salpeter value of 2.35.

TrueNTH sexual recovery study protocol: a multi-institutional collaborative approach to developing and testing a web-based intervention for couples coping with the side-effects of prostate cancer treatment in a randomized controlled trial

BACKGROUND

Over half of men who receive treatment for prostate suffer from a range of sexual problems that affect negatively their sexual health, sexual intimacy with their partners and their quality of life. In clinical practice, however, care for the sexual side effects of treatment is often suboptimal or unavailable. The goal of the current study is to test a web-based intervention to support the recovery of sexual intimacy of prostate cancer survivors and their partners after treatment.

METHODS

The study team developed an interactive, web-based intervention, tailored to type of treatment received, relationship status (partnered/non-partnered) and sexual orientation. It consists of 10 modules, six follow the trajectory of the illness and four are theme based. They address sexual side effects, rehabilitation, psychological impacts and coaching for self-efficacy. Each includes a video to engage participants, psychoeducation and activities completed by participants on the web. Tailored strategies for identified concerns are sent by email after each module. Six of these modules will be tested in a randomized controlled trial and compared to usual care. Men with localized prostate cancer with partners will be recruited from five academic medical centers. These couples (N = 140) will be assessed prior to treatment, then 3 months and 6 months after treatment. The primary outcome will be the survivors' and partners' Global Satisfaction with Sex Life, assessed by a Patient Reported Outcome Measure Information Systems (PROMIS) measure. Secondary outcomes will include interest in sex, sexual activity, use of sexual aids, dyadic coping, knowledge about sexual recovery, grief about the loss of sexual function, and quality of life. The impact of the intervention on the couple will be assessed using the Actor-Partner Interaction Model, a mixed-effects linear regression model able to estimate both the association of partner characteristics with partner and patient outcomes and the association of patient characteristics with both outcomes.

DISCUSSION

The web-based tool represents a novel approach to addressing the sexual health needs of prostate cancer survivors and their partners that-if found efficacious-will improve access to much needed specialty care in prostate cancer survivorship.

TRIAL REGISTRATION

Clinicaltrials.gov registration # NCT02702453 , registered on March 3, 2016.

[Eosinophilia heralding the diagnosis of eosinophilic fasciitis (Shulman's disease)]

INTRODUCTION

Eosinophilic fasciitis or Shulman's disease is characterized, in its typical form, by palpable thickening of the skin and soft tissues, blood hypereosinophilia and fascia lesions. We hereby report a case of eosinophilic fasciitis in which hypereosinophilia preceded for several months the clinical signs of fasciitis.

CASE REPORT

A 64-year-old woman, with a history of Little's syndrome with motor disability, was admitted in internal medicine for eosinophilia. For almost three months, no origin to the eosinophilia was found. The secondary onset of an edema and pain located on four limbs led to the diagnosis of eosinophilic fasciitis. Muscle magnetic resonance imaging was supportive and the muscle histological analysis confirmed the diagnosis of eosinophilic fasciitis. Treatment with steroids induced a rapid normalization of the eosinophilia and edema.

CONCLUSION

In this case report, eosinophilia was preceding the clinical cutaneous signs that led to the diagnosis of eosinophilic fasciitis. It is likely to believe that myalgias, frequently found in the onset of eosinophilic fasciitis, may have been hidden by the history of infantile encephalopathy. The diagnosis of eosinophilic fasciitis must be kept in mind of physicians in the investigation of an eosinophilia, even though cutaneous signs are lacking.

Outpatient parenteral antimicrobial therapy for infective endocarditis in patients over 80 years

OBJECTIVE

The incidence of infective endocarditis is progressively increasing, especially in elderly patients. Outpatient parenteral antibiotic therapy (OPAT) is being an excellent alternative for treatment, but advanced age is one of the relative contraindications. The aim of this study is to compare the characteristics and prognosis of patients less or more than 80 years, treated with OPAT.

METHODS

One hundred and ninety four patients were included between 1996 and 2015, 31 of them older than 80 years.

RESULTS

The most frequently affected valve is the aortic one, mainly native valves. Most used antibiotics are ceftriaxone, ampicillin, cloxacillin and daptomycin. Differences in surgery (39.9% vs 9.7%, p=0.001) and use of infusion pump (55.2% vs 35.5%; p= 0.044) were observed, under 80 years and older respectively. No differences in readmissions and mortality were observed.

CONCLUSIONS

OPAT could be considered an effective alternative for appropriately-selected elderly patients with infective endocarditis.

Antenatal antipsychotic exposure induces multigenerational and gender-specific programming of adiposity and glucose tolerance in adult mouse offspring

Second-generation antipsychotics (SGAs) are well known for their metabolic side effects in humans, including obesity and diabetes. These compounds are maintained during pregnancy to prevent the relapse of psychoses, but they readily diffuse across the placenta to the fetus, as documented with the widely-prescribed drug olanzapine (OLZ). However, observational studies have provided conflicting results on the potential impact of SGAs on fetal growth and body weight, and their effects on metabolic regulation in the offspring. For this reason, our study has tested whether antenatal exposure of CD1 mice to OLZ influenced metabolic outcomes in the offspring of the first (F1) and second (F2) generations. In F1 mice, OLZ antenatal treatment caused a decrease in neonatal body weight in both genders, an effect that persisted throughout life only in male animals. Interestingly, F1 female mice also displayed altered glucose homoeostasis. F2 mice, generated by mating normal males with F1 female mice exposed to OLZ during antenatal life, exhibited higher neonatal body weights which persisted only in F2 female animals. This was associated with expansion of fat mass and a concordant pattern of adipose tissue gene expression. Moreover, male and female F2 mice were glucose-intolerant. Thus, our study has demonstrated that antenatal OLZ exposure induces multigenerational and gender-specific programming of glucose tolerance in the offspring mice as adults, and points to the need for careful monitoring of children exposed to SGAs during pregnancy.

Low serum selenium concentrations in French patients with measles

Objective

Selenium deficiency adversely affects the clinical outcome of measles in the tropics. In developed countries, serum selenium level has never been investigated during acute measles. The aim of this study was to determine serum selenium concentrations in French patients with acute measles and to seek correlations with clinical and virological findings.

Patients and methods

We studied serum selenium concentrations in 94 French patients with acute measles and in 99 healthy controls matched for age and sex.

Results

The mean of selenium concentration was significantly lower in the patients than in the controls (46.4 ± 14.1 μg/L versus 86.5 ± 13.9 μg/L, P < 0.0001). In the patients, selenium concentrations were not associated with age, sex, vaccination status, clinical signs or specific antibody responses. Selenium levels did not differ significantly between patients with uncomplicated measles (45.8 ± 14.2 μg/L) and patients with complications (52.7 ± 13.2 μg/L) (P = 0.15).

Conclusion

Acute measles is associated with significant reduction of selenium level that did not seem to negatively affect the course of the disease suggesting compensating mechanisms in patients from developed countries against the disease.

Glucose supplementation has minimal effects on blood neutrophil function and gene expression in vitro

During early lactation, glucose availability is low and the effect of glucose supply on bovine polymorphonuclear leukocyte (PMNL) function is poorly understood. The objective of this study was to determine the effect of glucose supplementation on the function and transcriptomic inflammatory response of PMNL from cows in early and mid-lactation in vitro. Twenty Holstein cows in early (n=10; days in milk=17±3.1) and mid-lactation (n=10; days in milk=168±14.8) were used for this study. Jugular blood was analyzed for serum concentrations of nonesterified fatty acids, β-hydroxybutyrate, and glucose. Polymorphonuclear leukocytes were isolated and diluted using RPMI (basal glucose concentration was 7.2 mM) to different concentrations of PMNL/mL for phagocytosis, chemotaxis, gene expression, and medium analyses. Working solutions of glucose (0 or 4 mM of d-glucose) and lipopolysaccharide (0 or 50μg/mL) were added and tubes were incubated for 120 min at 37°C. Media were analyzed for concentrations of glucose and tumor necrosis factor-α (TNF-α). Data were analyzed in a randomized block (stage of lactation) design. Challenge with lipopolysaccharide increased the expression of the genes encoding for nuclear factor kappa B (NFKB1), IL-10 (IL10), IL1B, IL6, IL8, TNF-α (TNFA), glucose transporter 3 (SLC2A3), and the concentration of TNF-α in medium (147.3 vs. 72.5 pg/mL for lipopolysaccharide and control, respectively). Main effect of stage of lactation was minimal where the expression of IL10 increased for cows in early compared with cows in mid-lactation. After lipopolysaccharide challenge, cows in early lactation experienced more marked increases in the expression of IL6, TNFA, and IL8 when compared with cows in mid-lactation. Glucose supplementation had minimal effects on gene expression where glucose supplementation increased the expression of lysozyme (LYZ). Glucose supplementation increased PMNL phagocytosis but did not alter chemotaxis, morphology, or concentration of TNF-α in the medium. Under the conditions of the experiment, stage of lactation had minimal effects on PMNL response to glucose supply where only the expression of NFKB1 and the production of TNF-α were greater for cows in mid-lactation when compared with early lactation. Metabolic profiles for cows in early lactation did not parallel those for cows during the early postpartum period and may partly explain results for this study. Future studies investigating the effect of glucose supply on bovine PMNL function in vivo and how this may be altered by stage of lactation are warranted.

International multi-center evaluation of a novel chemiluminescence assay for the detection of anti-dsDNA antibodies

OBJECTIVE

Anti-double stranded desoxyribonucleic acid (anti-dsDNA) antibodies are considered fairly specific for systemic lupus erythematosus (SLE) and their quantification is useful for the clinical management of SLE patients. We assessed the diagnostic performance of the QUANTA Flash dsDNA chemiluminescent immunoassay (CIA) in comparison to an ELISA, using patients from five participating countries. The main focus was to evaluate the correlation between anti-dsDNA antibody results from the CIA and global SLE disease activity, as measured by the SLE Disease Activity Index 2000 (SLEDAI-2K).

PATIENTS AND METHODS

A total of 1431 samples (SLE, n = 843; disease controls, n = 588) from five countries (Canada, USA, Portugal, Sweden and Spain) were tested with QUANTA Flash dsDNA (Inova Diagnostics, San Diego, CA, USA). Data obtained with the QUANTA Lite dsDNA SC ELISA (Inova Diagnostics) were available for samples from three sites (Canada, USA and Sweden, n = 566). The SLEDAI-2K scores were available for 805 SLE patients and a cut-off of > 4 was used to define active disease.

RESULTS

QUANTA Flash dsDNA had a sensitivity of 54.3% for the diagnosis of SLE, combined with 89.8% specificity. Anti-dsDNA antibody levels were significantly higher (p < 0.0001) in active SLE (SLEDAI-2K > 4; n = 232; median value 83.0 IU/mL) versus the inactive patients (n = 573; median value 22.3 IU/mL), and the SLEDAI-2K scoring correlated with their dsDNA antibody levels (Spearman's rho = 0.44, p < 0.0001). Similar but less pronounced findings were also found for the ELISA, in relation to disease activity.

CONCLUSIONS

The QUANTA Flash dsDNA assay showed good clinical performance in a large international multi-center study. Additionally, the strong correlation between anti-dsDNA antibody results and SLEDAI-2K scores supported the potential utility of QUANTA Flash dsDNA for monitoring disease activity.

Feasibility of Flat Panel Detector CT in Perfusion Assessment of Brain Arteriovenous Malformations: Initial Clinical Experience

The different results from flat panel detector CT in various pathologies have provoked some discussion. Our aim was to assess the role of flat panel detector CT in brain arteriovenous malformations, which has not yet been assessed. Five patients with brain arteriovenous malformations were studied with flat panel detector CT, DSC-MR imaging, and vessel-encoded pseudocontinuous arterial spin-labeling. In glomerular brain arteriovenous malformations, perfusion was highest next to the brain arteriovenous malformation with decreasing values with increasing distance from the lesion. An inverse tendency was observed in the proliferative brain arteriovenous malformation. Flat panel detector CT, originally thought to measure blood volume, correlated more closely with arterial spin-labeling-CBF and DSC-CBF than with DSC-CBV. We conclude that flat panel detector CT perfusion depends on the time point chosen for data collection, which is triggered too early in these patients (ie, when contrast agent appears in the superior sagittal sinus after rapid shunting through the brain arteriovenous malformation). This finding, in combination with high data variability, makes flat panel detector CT inappropriate for perfusion assessment in brain arteriovenous malformations.

Body size and vocalization in primates and carnivores

A fundamental assumption in bioacoustics is that large animals tend to produce vocalizations with lower frequencies than small animals. This inverse relationship between body size and vocalization frequencies is widely considered to be foundational in animal communication, with prominent theories arguing that it played a critical role in the evolution of vocal communication, in both production and perception. A major shortcoming of these theories is that they lack a solid empirical foundation: rigorous comparisons between body size and vocalization frequencies remain scarce, particularly among mammals. We address this issue here in a study of body size and vocalization frequencies conducted across 91 mammalian species, covering most of the size range in the orders Primates (n = 50; ~0.11-120 Kg) and Carnivora (n = 41; ~0.14-250 Kg). We employed a novel procedure designed to capture spectral variability and standardize frequency measurement of vocalization data across species. The results unequivocally demonstrate strong inverse relationships between body size and vocalization frequencies in primates and carnivores, filling a long-standing gap in mammalian bioacoustics and providing an empirical foundation for theories on the adaptive function of call frequency in animal communication.

[Uncommon cutaneous presentation of visceral Leishmaniasis associated with HIV]

BACKGROUND

Visceral leishmaniasis is not normally expressed in skin. Herein, we describe the case of an HIV-positive patient who developed two unusual skin manifestations during an episode of visceral leishmaniasis.

PATIENTS AND METHODS

A 48-year-old female patient consulted initially for infiltrated purpura of all four limbs. Skin biopsy revealed leukocytoclastic vasculitis with Leishman-Donovan bodies. Laboratory tests showed medullary, splenic, gastric and colic involvement, suggesting systemic disease, and enabling visceral leishmaniasis to be diagnosed. Two years later, despite prolonged treatment, the patient presented maculopapular exanthema, and histology revealed persistent Leishman-Donovan bodies.

DISCUSSION

We report herein an association of two rare skin manifestations in an HIV-positive patient with visceral leishmaniasis: infiltrated purpura and maculopapular exanthema. However, the underlying mechanisms remain hypothetical. The initial leukocytoclastic exanthema could be secondary to either polyclonal hypergammaglobulinaemia or to IgA deposits, or possibly to mechanical impairment of blood vessels by the actual parasite. The maculopapular exanthema occurring later raised the possibility of post-Kala-Azar leishmaniasis due to blood-borne dissemination in an anergic subject or perhaps even immune reconstitution inflammatory syndrome.