Exploring pressures, tissue reperfusion and body positioning: a pilot evaluation

OBJECTIVE

To assess the relationship in healthy adults and critically ill patients between: patient position, body mass index (BMI), patient body temperature, interface pressure (IP) and tissue reperfusion (TR). Also to determine the relationship in critically ill patients between: Sequential Organ Failure Assessment (SOFA) score, Braden Scale score for predicting pressure injury risk, Acute Physiology and Chronic Health Evaluation II (APACHE II) severity of disease classification score, IP and TR.

METHODS

This study took place in a 27-bed intensive care unit (ICU) of an Australian tertiary hospital. IP and TR outcomes were measured at the sacrum and greater trochanter. Repeated measures analyses of variance (ANOVAs) and doubly multivariate repeated measures ANOVAs were conducted using peak pressure index (PPI), peak time (PT), settled time constant (STC) and normalised hyperaemic area (NHA) measures of TR as outcomes. Participant type, body mass index (BMI), Braden and APACHE II scores and patient body temperature were considered as between-groups factors and covariates.

RESULTS

We recruited 23 low- and high-acuity ICU patients and nine healthy adult volunteers. Not all IP readings could be obtained from ICU patients. TR readings were collected from all recruited patients, but not all TR measurements were mutually uncorrelated. Controlling for age, PPI readings differed between participant types (p=0.093), with the highest values associated with high-acuity patients and the lowest with healthy adults; the association was not substantive when controlling for age and BMI. Age was a significant variable (p=0.008), with older participants having higher scores than younger ones. No statistically significant associations between any measured parameter and TR variables were observed. However, temperature was revealed to be related to TR (p=0.091).

CONCLUSIONS

Although not powered to detect significant effects, this pilot analysis has determined several associations of importance, with differences in outcomes observed between low- and high-acuity ICU patients; and between ICU patients and healthy volunteers.

Tests of General Relativity with GW170817

The recent discovery by Advanced LIGO and Advanced Virgo of a gravitational wave signal from a binary neutron star inspiral has enabled tests of general relativity (GR) with this new type of source. This source, for the first time, permits tests of strong-field dynamics of compact binaries in the presence of matter. In this Letter, we place constraints on the dipole radiation and possible deviations from GR in the post-Newtonian coefficients that govern the inspiral regime. Bounds on modified dispersion of gravitational waves are obtained; in combination with information from the observed electromagnetic counterpart we can also constrain effects due to large extra dimensions. Finally, the polarization content of the gravitational wave signal is studied. The results of all tests performed here show good agreement with GR.

[Catatonia education in France: A cross-sectional study]

OBJECTIVES

Catatonia is a transnosographic syndrome described by K. Kahlbaum in 1874. Catatonia can be life-threatening due to its complications and in case of malignant catatonia. Safe and effective treatments have been identified (benzodiazepines and electro-convulsive-therapy). The prevalence of this syndrome is important and represents about 10% of inpatients in an acute psychiatric ward. However, this syndrome appears to remain under-diagnosed and poorly known. We were, therefore, interested in the current knowledge of French psychiatry residents and young psychiatrists as well as the education they had received about catatonia.

METHODS

A questionnaire was submitted to French psychiatry residents and young psychiatrists with fewer than 5 years of experience. It included questions about knowledge of the symptoms, complications, causes and treatments of catatonia. Participants were also asked about their confidence in the management of a patient with catatonia and about the number of catatonic patients they had already met. The type of lecture and teaching about catatonia was also assessed.

RESULTS

Among the 376 psychiatrists that completed the questionnaire, 37.5% never had received any specific teaching about catatonia. Concerning the 62.5% who benefited from a specific lecture, this was mainly delivered as part of psychiatry DES. Heterogeneity in the education delivery on the French territory had been highlighted. In addition, participants' knowledge of catatonic syndrome seems incomplete. However, knowledge of catatonic symptoms and first intention treatments was significantly better among respondents who were part of the "with education" group. The confidence in catatonia recognition and management, as well as the number of catatonic patients they met, are also significantly higher in the group "with education".

CONCLUSION

Specific education seems to improve the knowledge of young doctors and their ability to diagnose and treat catatonic patients. This education remains poorly provided and heterogeneous on the French territory. Catatonia deserves a place in the teaching program of the psychiatry DES, thus to become systematic.

Neutron diffraction of deuterated tripalmitin and the influence of shear on its crystallisation

This neutron diffraction study of deuterated tripalmitin has provided further insight into a forensic observation of the crystallisation of lipids under high-shear conditions. To achieve this, an experimental set up was designed to enable simultaneous rheological data from a Couette cell to be recorded with neutron powder diffraction, enabling the influence of shear on the polymorph transformation on cooling to be monitored in real time. Tripalmitin was observed to directly transform from a liquid phase to a β polymorph under the influence of shear. Although the liquid to β transition was not observed to be influenced by shear rate, the degree of crystallinity, qualitatively denoted by an increase in the sharpness of the diffraction peaks, was observed at higher shear rates. Evidence is also presented that the rate of cooling influences the ordering in the β-polymorph produced in zero shear conditions.

Abstract P1-19-02: Innovation in diagnosis and treatment of brain metastases using multifunctional nanomedicines

Systemic therapies have limited efficacy against brain metastases, largely because passive delivery of naked compounds via the bloodstream does not achieve sufficiently high or evenly dispersed intratumoural concentrations. Heterogeneous tissue architecture, abnormal perfusion, hypoxic zones and high interstitial fluid pressure are key factors limiting drug delivery, compounded by patchy blood-tumour-barrier permeability. Also, brain metastases are usually detected late, once patients become symptomatic. We are investigating whether engineered biopharmaceuticals might improve diagnostic sensitivity for earlier detection, as well as therapeutic efficacy and side-effect profiles of existing agents through active tumour targeting, delayed clearance and microenvironment-mediated activation. This study is proceeding with parallel preclinical and clinical tracks.

Preclinical aims: (1) Develop and characterise monoclonal antibody (mAb) fragments (scFvs) that target the brain metastasis markers HER2 and HER3; (2) Functionalise polyethylene glycol (PEG)-based nanocarriers with the scFvs, along with imaging agents to facilitate in vivoand ex vivoanalysis of tissue distribution; (3) Functionalise HER2/3-targeted carriers with doxorubicin via an acid-labile hydrazone bond for release in hypoxic environments, or the endosome compartment after internalization. Results to date. His-tagged HER2- and HER3-targeted scFvs based on ligand-binding sequences of clinically-approved mAbs were expressed and purified from Expi293 suspension cultures. Binding affinities are an order of magnitude stronger than parent mAbs (KD 2-8x10E-11M), determined using surface plasmon resonance analysis. The scFvs are cytostatic and moderately cytotoxic in vitro, with IC50s in order of 0.4-1.0μM. HER2 and HER3 scFvs exhibited dose-dependent, additive growth inhibition when used in combination, and induced internalisation of their receptor ligands within 4 hours in SKBr3 cells. Conclusions.The scFvs are strong carrier-tethering candidates in terms of both extracellular and intracellular payload release. Carrier synthesis is currently underway and preliminary in vivo data will be presented.

Clinical aims: (1) Develop and characterise 89Zirconium-labelled HER2-targeted PET tracers based on parent mAb and scFv; (2) Compare uptake and retention of the tracers in breast cancer patients with brain metastases; (3) Computationally relate tumour uptake to the administered dose, perfusion, tumour size and HER2 expression; (4) Determine the uptake range within and between patients, and the minimum size for reliable detection. Results to date. The mAb tracer has been synthesised, characterised and labelling processes scaled for clinical production. It is stable in physiologic conditions, retains HER2-binding activity and has a favourable biodistribution profile in NOD-SCID mice bearing BT474 xenografts. Conclusions. Australian regulatory approvals are in place and recruitment for the mAb imaging trial ("BoNSAI") has begun. Preliminary data will be presented.

Citation Format: Saunus JM, Lim M, Puttick S, Kalita-de Croft P, Houston ZH, Jones ML, Latter MJ, Campbell LC, Thomas P, Jeffree RL, Rose SE, Mahler SM, Thurecht KJ, Scott AM, Lakhani SR. Innovation in diagnosis and treatment of brain metastases using multifunctional nanomedicines [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-19-02.

Abstract OT2-09-02: A phase I dose escalation study of topical bexarotene in women at high risk for breast cancer

Background: Breast cancer prevention with anti-estrogens, including tamoxifen, raloxifene, and exemestane, has been shown to reduce the incidence of hormone receptor-positive breast cancer. However, agents that can reduce the incidence of hormone receptor negative breast cancer are currently lacking. Rexinoids such as bexarotene are vitamin A analogues that have been shown to be involved in cell differentiation, growth, and apoptosis. In preclinical mouse models that develop ER-negative breast cancers, bexarotene showed a significant reduction in mammary tumor development. Oral bexarotene has been evaluated in BRCA mutation carriers and significant decreases in cyclin D1 were noted in breast cells suggesting biological activity of bexarotene on breast tissue. Systemic side effects of hyperlipidemia and hypothyroidism were also found. Data from chemoprevention studies with topical 4-hydroxytamoxifen support the concept of topical agents penetrating into the breast tissue and exhibiting biological activity in the tissue. We hypothesize that topical bexarotene can be applied to the breast as a chemoprevention agent with penetration to the breast tissue without subsequent systemic side effects and toxicity as seen with oral bexarotene.

Trial Design: Women at high risk for breast cancer will be recruited and assigned to one of three different dose levels: 10mg (1ml) every other day, 10mg (1ml) daily, 20mg (2ml) daily to one unaffected breast for 4 weeks. The primary endpoint of the study is to determine the recommended phase II dose of topical bexarotene 1% gel for evaluation in healthy at-risk women. Dose Limiting Toxicity (DLT) is defined as a grade 2 skin adverse event that persists for at least 6 days or any grade 3 or greater adverse event related to the study drug. A grade 2 skin adverse event that recurs and persists for at least 3 days is also a DLT. The Maximum Tolerated Dose (MTD) will be defined as the highest dose level at which no more than 2 participants experience a DLT among 10 participants treated. A conservative modification of the standard “3+3” design will be applied. The first three participants will be assigned to the lowest dose level. New cohorts of 3-4 participants will not be treated until toxicity has been fully evaluated for all current participants through 4 weeks. Once the MTD has been determined, an expansion cohort of an additional 10 patients will be recruited at the MTD to further evaluate safety and toxicity at this dose level as well bexarotene concentration in the breast tissue. Secondary endpoints include serum bexarotene level, tissue bexarotene levels, and changes in thyroid function tests, lipid profile, and calcium. The planned accrual for this study if maximally accrued to all dose levels and the dose expansion cohort will be 40 participants.

Citation Format: Thomas PS, Patel AB, Contreras A, Liu DD, Lee JJ, Khan S, Vornik LA, Dimond EP, Perloff M, Heckman-Stoddard BM, Brown PH. A phase I dose escalation study of topical bexarotene in women at high risk for breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT2-09-02.

Abstract PD3-07: A phase II pre-surgical trial of lapatinib for the treatment of women with HER2 positive or EGFR positive ductal carcinoma in situ

Background: Estrogen receptor (ER)-negative tumors and human epidermal growth factor 2-Neu (HER2) positive breast cancers are known to be more clinically aggressive subtypes of breast cancer and account for 30% of all breast cancers. Women with HER2 + breast cancers, whether ER+ or ER -, require cytotoxic chemotherapy with a HER2-targeting agent, and often have adverse outcomes. Thus, preventive agents are needed to reduce the incidence of these subtypes of aggressive breast cancer. Lapatinib, a dual tyrosine kinase inhibitor, inhibits epidermal growth factor receptors (EGFR) and HER2 kinases and has shown to decrease breast cell proliferation in invasive breast cancer and adjacent premalignant lesions. Therefore, we conducted a multi-institutional randomized Phase II clinical trial to study the effects of the signal transduction inhibitor lapatinib in women with HER2-positive or EGFR-positive ductal carcinoma in situ (DCIS).

Methods: Randomized participants received either lapatinib (750mg, 1000mg, or 1500mg) or placebo daily for 2-6 weeks prior to their surgery. After minimal accrual, the trial was later amended to lapatinib 1000mg or placebo. Pre-treatment breast tissue was obtained from initial diagnostic core biopsy and post-treatment breast tissue was obtained from surgical excision specimen. Blood was obtained prior to surgery to assess serum lapatinib level. Participants kept a daily symptom assessment log and had a cardiac assessment at baseline and prior to surgery. Patients were instructed to take drug up to and including the day before surgery. The dual primary endpoint for this study was change in proliferation in pre- versus post-treatment biopsies between the two treatment arms, as measured by Ki67 as well as toxicity assessment. Secondary endpoints included incidence of DCIS at surgery and modulation of tissue biomarker expression in growth factor receptors (EGFR, ErbB2); phosphorylated growth factor receptor (phospho-ErbB2); signal transduction markers (MAPK, phospho-MAPK); hormone receptors (ER, PR); and p27.

Results:Twenty-two women (mean age: 51; range: 32-66) with HER2+ or EGFR+ DCIS were treated with lapatinib (1,000 or 1,500 mg) or placebo for 2–6 weeks prior to surgical excision. Ki67 expression was significantly decreased in the lapatinib treatment arms compared to placebo (p=0.0122). Diarrhea, fatigue, and skin reactions were notable adverse events that occurred predominately in the lapatinib arm compared to placebo. No grade 3 or 4 events related to the study drug were noted during the study. No changes were noted in cardiac function. DCIS was present in all surgical specimens in both arms. Invasive breast cancer was noted in 1 patient on lapatinib 1000mg and 3 patients on placebo. No statistically significant changes were noted in signal transduction biomarkers

Conclusion:These results demonstrate the effectiveness of lapatinib in reducing proliferation in women with EGFR+ or HER2+ DCIS. Even low-grade toxicities can deter use of an agent in the prevention setting. This and the lack of a risk model for HER2+ and triple negative breast cancer make the development of larger scale clinical prevention trials of lapatinib for the prevention a challenge.

Citation Format: Thomas PS, Contreras A, Pruthi S, Krontiras H, Rimawi M, Garber J, Wang T, Hilsenbeck SG, Vornik LA, Gilmer T, Friedman R, Heckman-Stoddard BM, Dunn B, Kuerer H, Brown PH. A phase II pre-surgical trial of lapatinib for the treatment of women with HER2 positive or EGFR positive ductal carcinoma in situ [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr PD3-07.

Constraining the p-Mode-g-Mode Tidal Instability with GW170817

We analyze the impact of a proposed tidal instability coupling p modes and g modes within neutron stars on GW170817. This nonresonant instability transfers energy from the orbit of the binary to internal modes of the stars, accelerating the gravitational-wave driven inspiral. We model the impact of this instability on the phasing of the gravitational wave signal using three parameters per star: an overall amplitude, a saturation frequency, and a spectral index. Incorporating these additional parameters, we compute the Bayes factor (lnB_{!pg}^{pg}) comparing our p-g model to a standard one. We find that the observed signal is consistent with waveform models that neglect p-g effects, with lnB_{!pg}^{pg}=0.03_{-0.58}^{+0.70} (maximum a posteriori and 90% credible region). By injecting simulated signals that do not include p-g effects and recovering them with the p-g model, we show that there is a ≃50% probability of obtaining similar lnB_{!pg}^{pg} even when p-g effects are absent. We find that the p-g amplitude for 1.4  M_{⊙} neutron stars is constrained to less than a few tenths of the theoretical maximum, with maxima a posteriori near one-tenth this maximum and p-g saturation frequency ∼70  Hz. This suggests that there are less than a few hundred excited modes, assuming they all saturate by wave breaking. For comparison, theoretical upper bounds suggest ≲10^{3} modes saturate by wave breaking. Thus, the measured constraints only rule out extreme values of the p-g parameters. They also imply that the instability dissipates ≲10^{51}  erg over the entire inspiral, i.e., less than a few percent of the energy radiated as gravitational waves.

Serum Procalcitonin and C-reactive Protein as Markers of Sepsis and Outcome in Patients with Neurotrauma and Subarachnoid Haemorrhage

This prospective study evaluated serum procalcitonin (PCT) and C-reactive protein (CRP) as markers for systemic inflammatory response syndrome (SIRS)/sepsis and mortality in patients with traumatic brain injury and subarachnoid haemorrhage. Sixty-two patients were followed for 7 days. Serum PCT and CRP were measured on days 0, 1, 4, 5, 6 and 7.

Seventy-seven per cent of patients with traumatic brain injury and 83% with subarachnoid haemorrhage developed SIRS or sepsis (P=0.75). Baseline PCT and CRP were elevated in 35% and 55% of patients respectively (P=0.03). There was a statistically non-significant step-wise increase in serum PCT levels from no SIRS (0.4±0.6 ng/ml) to SIRS (3.05±9.3 ng/ml) to sepsis (5.5±12.5 ng/ml). A similar trend was noted in baseline PCT in patients with mild (0.06±0.9 ng/ml), moderate (0.8±0.7 ng/ml) and severe head injury (1.2±1.9 ng/ml). Such a gradation was not observed with serum CRP. There was a non-significant trend towards baseline PCT being a better marker of hospital mortality compared with baseline CRP (ROC-AUC 0.56 vs 0.31 respectively). This is the first prospective study to document the high incidence of SIRS in neurosurgical patients. In our study, serum PCT appeared to correlate with severity of traumatic brain injury and mortality. However, it could not reliably distinguish between SIRS and sepsis in this cohort. This is in part because baseline PCT elevation seemed to correlate with severity of injury. Only a small proportion of patients developed sepsis, thus necessitating a larger sample size to demonstrate the diagnostic usefulness of serum PCT as a marker of sepsis. Further clinical trials with larger sample sizes are required to confirm any potential role of PCT as a sepsis and outcome indicator in patients with head injuries or subarachnoid haemorrhage.

Search for Subsolar-Mass Ultracompact Binaries in Advanced LIGO's First Observing Run

We present the first Advanced LIGO and Advanced Virgo search for ultracompact binary systems with component masses between 0.2  M_{⊙}-1.0  M_{⊙} using data taken between September 12, 2015 and January 19, 2016. We find no viable gravitational wave candidates. Our null result constrains the coalescence rate of monochromatic (delta function) distributions of nonspinning (0.2  M_{⊙}, 0.2  M_{⊙}) ultracompact binaries to be less than 1.0×10^{6}  Gpc^{-3}  yr^{-1} and the coalescence rate of a similar distribution of (1.0  M_{⊙}, 1.0  M_{⊙}) ultracompact binaries to be less than 1.9×10^{4}  Gpc^{-3}  yr^{-1} (at 90% confidence). Neither black holes nor neutron stars are expected to form below ∼1  M_{⊙} through conventional stellar evolution, though it has been proposed that similarly low mass black holes could be formed primordially through density fluctuations in the early Universe and contribute to the dark matter density. The interpretation of our constraints in the primordial black hole dark matter paradigm is highly model dependent; however, under a particular primordial black hole binary formation scenario we constrain monochromatic primordial black hole populations of 0.2  M_{⊙} to be less than 33% of the total dark matter density and monochromatic populations of 1.0  M_{⊙} to be less than 5% of the dark matter density. The latter strengthens the presently placed bounds from microlensing surveys of massive compact halo objects (MACHOs) provided by the MACHO and EROS Collaborations.

Raman spectra and structural peculiarities of TeO2-TeO3 mixed oxides

Raman spectra of the mixed crystalline oxides of the (1  -  x)TeO₂  +  xTeO₃ (x  =  0, ¼, ½, 1) series were recorded and simulated by using the DFT calculations. Good agreement between observed and calculated Raman spectra makes it possible to establish unambiguous assignment for all prominent Raman lines. This result gives an insight into relations between structural peculiarities and observed spectral features for the crystals promising as nonlinear optical materials. Highlights • Several mixed TeO₂-TeO₃ crystals were synthesized by solid-state chemistry • DFT calculations well describe structures and phonon spectra of TeO₂-TeO₃ oxides • Raman lines can be assigned to internal vibrations of TeO₄ and TeO₆ polyhedrons • Observed Raman bands can be used as fingerprints of different structural units.

[Socio-demographic and clinical characteristics of adolescents hospitalized in French units for inmates: Results of a cross-sectional study]

BACKGROUND

In France, on the first of January 2018, 772 underage persons were in jail or about 1.1 % of the incarcerated population. The prevalence of psychiatric disorders among those inmates is high. As a result psychiatric care (and particularly full-time hospitalization) is essential for this population. The unités hospitalières spécialement aménagées (UHSA) are full-time inpatient hospitalization units for inmates in France. Adults but also underage inmates can be admitted to UHSA for voluntary or involuntary hospitalization. However, no study about the characteristics of young patients admitted to UHSA is currently available. The aim of this study is to describe the population of children and adolescent patients hospitalized in these facilities and to evaluate the care provided.

METHOD

We conducted a retrospective study, including all the patients under 18 years of age, who have been hospitalized in UHSA since its creation in 2010 until 31 December 2016. Anonymized data concerning socio-demographic profile, clinical symptoms and care provided have been collected from the medical records of each patient.

RESULTS

Overall 80 underage patients were included, for 120 hospitalisations in UHSA. Those patients are mainly male (80%) with a mean age of 16.7 years. They are mostly hospitalized with their consent (59%) for stays of about 50 days and frequently after self-harm behaviours. The main diagnoses are anxiety disorders (26%) and psychotic disorders (25%). At the end, 86% of the patients are prescribed a psychotropic drug treatment and 40% of those medical drugs are prescribed outside the guidelines. Finally, several specific problems were identified. Especially, contact with families and educators or access to education programs are very challenging.

CONCLUSION

This study highlights the current difficulties encountered in the management of inmate underage patients in full-time psychiatric hospitalization. In this paper, we propose areas for improvement through (1) specific arrangements to receive young patients (specific service's management in order to reinforce the observation of those young people, to facilitate contact with their families, to improve the access to education programs, etc.); (2) specific arrangements in the treatment offered to young patients in UHSA (specific training course for nurses, specific therapeutic programs, etc.); (3) the development of networks working with psychiatric services inside and outside the prison, educators, families and prison services, in order to promote the continuity of cares.

GW170817: Measurements of Neutron Star Radii and Equation of State

On 17 August 2017, the LIGO and Virgo observatories made the first direct detection of gravitational waves from the coalescence of a neutron star binary system. The detection of this gravitational-wave signal, GW170817, offers a novel opportunity to directly probe the properties of matter at the extreme conditions found in the interior of these stars. The initial, minimal-assumption analysis of the LIGO and Virgo data placed constraints on the tidal effects of the coalescing bodies, which were then translated to constraints on neutron star radii. Here, we expand upon previous analyses by working under the hypothesis that both bodies were neutron stars that are described by the same equation of state and have spins within the range observed in Galactic binary neutron stars. Our analysis employs two methods: the use of equation-of-state-insensitive relations between various macroscopic properties of the neutron stars and the use of an efficient parametrization of the defining function p(ρ) of the equation of state itself. From the LIGO and Virgo data alone and the first method, we measure the two neutron star radii as R_{1}=10.8_{-1.7}^{+2.0}  km for the heavier star and R_{2}=10.7_{-1.5}^{+2.1}  km for the lighter star at the 90% credible level. If we additionally require that the equation of state supports neutron stars with masses larger than 1.97  M_{⊙} as required from electromagnetic observations and employ the equation-of-state parametrization, we further constrain R_{1}=11.9_{-1.4}^{+1.4}  km and R_{2}=11.9_{-1.4}^{+1.4}  km at the 90% credible level. Finally, we obtain constraints on p(ρ) at supranuclear densities, with pressure at twice nuclear saturation density measured at 3.5_{-1.7}^{+2.7}×10^{34}  dyn cm^{-2} at the 90% level.