Detecting changes in distortion product otoacoustic emission maps using statistical parametric mapping and random field theory

Distortion product otoacoustic emission (DPOAE) maps collect DPOAE emissions over a broad range of frequencies and ratios. One application of DPOAE mapping could be monitoring changes in intracranial pressure (ICP) in space, where non-invasive measures of ICP are an area of interest. Data were collected in two experiments to statistically assess changes in DPOAE maps. A repeatability study where four maps per subject were collected across four weeks to establish "normal" variability in DPOAE data, and a posture study where subjects were measured supine and prone with lower body negative pressure, lower body positive pressure (LBPP), and at atmospheric pressure. DPOAE amplitude maps were analyzed using statistical parametric mapping and random field theory. Postural changes produced regional changes in the maps, specifically in the range of 5-7.5 kHz and between primary tone ratios of 1.13-1.24. These regional changes were most pronounced in the prone LBPP condition, where amplitudes were lower from baseline for the Postural Cohort than the Repeatability Cohort. Statistical parametric mapping provided a sensitive measure of regional DPOAE map changes, which may be useful clinically to monitor ICP noninvasively in individuals or for research to identify differences within in cohorts of people.

CRISPR/Cas9-Mediated Foxp1 Silencing Restores Immune Surveillance in an Immunocompetent A20 Lymphoma Model

The interaction of lymphoma cells with their microenvironment has an important role in disease pathogenesis and is being actively pursued therapeutically using immunomodulatory drugs, including immune checkpoint inhibitors. Diffuse large B-cell lymphoma (DLBCL) is an aggressive high-grade disease that remains incurable in ~40% of patients treated with R-CHOP immunochemotherapy. The FOXP1 transcription factor is abundantly expressed in such high-risk DLBCL and we recently identified its regulation of immune response signatures, in particular, its suppression of the cell surface expression of major histocompatibility class II (MHC-II), which has a critical role in antigen presentation to T cells. Using CRISPR/Cas9 genome editing we have depleted Foxp1 expression in the aggressive murine A20 lymphoma cell line. When grown in BALB/c mice, this cell line provides a high-fidelity immunocompetent disseminated lymphoma model that displays many characteristics of human DLBCL. Transient Foxp1-depletion using siRNA, and stable depletion using CRISPR (generated by independently targeting Foxp1 exon six or seven) upregulated cell surface I-Ab (MHC-II) expression without impairing cell viability in vitro. RNA sequencing of Foxp1-depleted A20 clones identified commonly deregulated genes, such as the B-cell marker Cd19, and hallmark DLBCL signatures such as MYC-targets and oxidative phosphorylation. Immunocompetent animals bearing Foxp1-depleted A20 lymphomas showed significantly-improved survival, and 20% did not develop tumors; consistent with modulating immune surveillance, this was not observed in immunodeficient NOD SCIDγ mice. The A20 Foxp1 CRISPR model will help to further characterize the contribution of Foxp1 to lymphoma immune evasion and the potential for Foxp1 targeting to synergize with other immunotherapies.

Immunopeptidomic Profiling of HLA-A2-Positive Triple Negative Breast Cancer Identifies Potential Immunotherapy Target Antigens

The recent development in immune checkpoint inhibitors and chimeric antigen receptor (CAR) T-cells in the treatment of cancer has not only demonstrated the potency of utilizing T-cell reactivity for cancer therapy, but has also highlighted the need for developing new approaches to discover targets suitable for such novel therapeutics. Here we analyzed the immunopeptidomes of six HLA-A2-positive triple negative breast cancer (TNBC) samples by nano-ultra performance liquid chromatography tandem mass spectrometry (nUPLC-MS2 ). Immunopeptidomic profiling identified a total of 19 675 peptides from tumor and adjacent normal tissue and 130 of the peptides were found to have higher abundance in tumor than in normal tissues. To determine potential therapeutic target proteins, we calculated the average tumor-associated cohort coverage (aTaCC) that represents the percentage coverage of each protein in this cohort by peptides that had higher tumoral abundance. Cofilin-1 (CFL-1), interleukin-32 (IL-32), proliferating cell nuclear antigen (PCNA), syntenin-1 (SDCBP), and ribophorin-2 (RPN-2) were found to have the highest aTaCC scores. We propose that these antigens could be evaluated further for their potential as targets in breast cancer immunotherapy and the small cohort immunopeptidomics analysis technique could be used in a wide spectrum of target discovery. Data are available via ProteomeXchange with identifier PXD009738.

The European antibody network's practical guide to finding and validating suitable antibodies for research

Antibodies are widely exploited as research/diagnostic tools and therapeutics. Despite providing exciting research opportunities, the multitude of available antibodies also offers a bewildering array of choice. Importantly, not all companies comply with the highest standards, and thus many reagents fail basic validation tests. The responsibility for antibodies being fit for purpose rests, surprisingly, with their user. This paper condenses the extensive experience of the European Monoclonal Antibody Network to help researchers identify antibodies specific for their target antigen. A stepwise strategy is provided for prioritising antibodies and making informed decisions regarding further essential validation requirements. Web-based antibody validation guides provide practical approaches for testing antibody activity and specificity. We aim to enable researchers with little or no prior experience of antibody characterization to understand how to determine the suitability of their antibody for its intended purpose, enabling both time and cost effective generation of high quality antibody-based data fit for publication.

Cancer/Testis Antigen PASD1 Silences the Circadian Clock

The circadian clock orchestrates global changes in transcriptional regulation on a daily basis via the bHLH-PAS transcription factor CLOCK:BMAL1. Pathways driven by other bHLH-PAS transcription factors have a homologous repressor that modulates activity on a tissue-specific basis, but none have been identified for CLOCK:BMAL1. We show here that the cancer/testis antigen PASD1 fulfills this role to suppress circadian rhythms. PASD1 is evolutionarily related to CLOCK and interacts with the CLOCK:BMAL1 complex to repress transcriptional activation. Expression of PASD1 is restricted to germline tissues in healthy individuals but can be induced in cells of somatic origin upon oncogenic transformation. Reducing PASD1 in human cancer cells significantly increases the amplitude of transcriptional oscillations to generate more robust circadian rhythms. Our results describe a function for a germline-specific protein in regulation of the circadian clock and provide a molecular link from oncogenic transformation to suppression of circadian rhythms.

Increased Expression of Phosphorylated FADD in Anaplastic Large Cell and Other T-Cell Lymphomas

FAS-associated protein with death domain (FADD) is a major adaptor protein involved in extrinsic apoptosis, embryogenesis, and lymphocyte homeostasis. Although abnormalities of the FADD/death receptor apoptotic pathways have been established in tumorigenesis, fewer studies have analyzed the expression and role of phosphorylated FADD (pFADD). Our identification of FADD as a lymphoma-associated autoantigen in T-cell lymphoma patients raises the possibility that pFADD, with its correlation with cell cycle, may possess role(s) in human T-cell lymphoma development. This immunohistochemical study investigated pFADD protein expression in a range of normal tissues and lymphomas, particularly T-cell lymphomas that require improved therapies. Whereas pFADD was expressed only in scattered normal T cells, it was detected at high levels in T-cell lymphomas (eg, 84% anaplastic large cell lymphoma and 65% peripheral T cell lymphomas, not otherwise specified). The increased expression of pFADD supports further study of its clinical relevance and role in lymphomagenesis, highlighting phosphorylation of FADD as a potential therapeutic target.

First clinical results with a real time, electronic imager as an aid to colonoscopy

The early clinical results are described of a real time, electromagnetic imaging system as an aid to colonoscopy. After gaining experience with the use of the system, one experienced endoscopist was randomised to perform consecutive colonoscopies either with (n = 29) or without (n = 26) the imager view. All procedures were recorded on computer disk and replayed for retrospective analysis. Total colonoscopy was achieved in all patients except one (imager view not available). Comparing intubation time and duration of loop formation per patient, there was no significant difference between the two study groups. The number of attempts taken to straighten the colonoscope pre patient, however, was less when the endoscopist was able to see the imager view, p = 0.03. Hand pressure was also more effective when the endoscopist and endoscopy assistant could see the imager display, p = 0.02. Preliminary experience suggests that real time, electronic imaging of colonoscopy is safe, effective, and will improve the accuracy of the procedure.

Pharmacological properties of the natural marine product furospongin-1

1. The natural marine product, furospongin-1 (6, 12 and 24.5 mumol/L) significantly inhibited contractions of segments of guinea-pig ileum induced by submaximal concentrations (0.1 mumol/L) of acetylcholine (ACh) and histamine. Furospongin-1 (24.5 and 36.7 mumol/L) reduced both the phasic and tonic components of a contraction induced by 30 mumol/L K+ solution in the absence and presence of atropine (1 mumol/L), mepyramine (1 mumol/L) and phentolamine (1 mumol/L). Furospongin-1 also decreased basal tension and the amplitude of spontaneous phasic contractions of guinea-pig ileum. 2. The mitochondrial ATP synthase inhibitor oligomycin (0.3, 1 and 3 mumol/L) had a similar concentration-dependent action, reducing basal activity and contractions evoked by histamine and ACh. Oligomycin also reduced both the phasic and tonic components of a contraction induced by 30 mmol/L K+ solution in the absence and presence of atropine (1 mumol/L), mepyramine (1 mumol/L) and phentolamine (1 mumol/L). 3. Furospongin-1 (6 and 37.6 mumol/L) and oligomycin (3 mumol/L) had no effect on contractions of chemically skinned guinea-pig ileum longitudinal muscle segments. In this same tissue, furospongin-1 (6, 12 and 24.5 mumol/L) and oligomycin (0.3, 1 and 3 mumol/L) concentration-dependently reduced tissue levels of ATP. 4. In lyzed bovine mitochondria, oligomycin (0.1, 0.3, 1 and 3 mumol/L) inhibited conversion of ATP to ADP whilst furospongin-1 (6, 12 and 24.5 mumol/L) and carbonyl cyanide m-chlorophenylhydrazone (0.5 mmol/L) had no significant effect on ATP breakdown.(ABSTRACT TRUNCATED AT 250 WORDS)

The marine natural product 3,5-dibromo-2-(2,4-dibromo-phenoxy)phenol, inhibits contractile activity in the guinea-pig ileum

1. The tetrabrominated diphenyl ether 3,5-dibromo-2-(2,4-dibromophenoxy)phenol (BPE), a natural marine product isolated from a sponge, was tested for pharmacological activity in guinea-pig ileum. 2. BPE (2 mumol/L) decreased basal force and the frequency of spontaneous contractions of the ileum. It also significantly decreased contractions of the ileum induced by 5 mmol/L barium and to electrical stimulation at parameters which stimulated intrinsic nerves. 3. The slopes of concentration-response curves to acetylcholine (ACh), histamine and 5-hydroxytryptamine (5-HT) were significantly reduced by BPE at concentrations of 2 mumol/L or greater. 4. BPE (2 mumol/L) did not affect calcium-induced contractions of longitudinal muscle fibres from guinea-pig ileum which were stripped of their cellular membrane. It (6 mumol/L) also had no effect on ATP levels in longitudinal muscle fibres. 5. BPE (2 mumol/L) reduced both phasic and tonic components of contractions induced by raising the extracellular concentration of K+ to 15, 30, 45 or 60 mmol/L (in the presence of atropine, propranolol, phentolamine and desensitization to 5-HT to inhibit the effects of nerve transmitter release). 6. BPE (2 mumol/L) reduced carbachol-induced contractions of ileum pre-incubated in 1 mumol/L felodipine, a blocker of L-type voltage-operated calcium channels (VOCC). 7. BPE dose dependently (0.6-6 mumol/L) reduced contractions induced by Ca2+ in both K+ depolarized ileum and in tissue exposed to carbachol (10 mumol/L) in the presence of felodipine (0.1 mumol/L). 8. These results suggest that BPE affects intracellular messenger systems controlling cytosolic calcium and/or blocks entry of calcium into the cell through both VOCC and receptor-operated channels (ROC).

Non-radiological technique for three-dimensional imaging of endoscopes

A novel system is described which images in three dimensions, the total configuration of a colonoscope without the use of conventional radiological techniques. A low intensity magnetic field is used in conjunction with a miniature inductive sensor. The system intrinsically safe and it is potentially inexpensive and capable of being used in a normal hospital environment. Clinical trials are described in which the system is validated in terms of its suitability for the application. Magnetic and conventional X-ray images obtained ex vivo with the endoscope held in various configurations and comparisons in the patients confirm the practical applicability of the new system.

A robot-controlled microwave antenna system for uniform hyperthermia treatment of superficial tumours with arbitrary shape

A system for microwave hyperthermia by scanning an antenna 'footprint' over a disease site is demonstrated. A computer-controlled robot arm scans a 2.45 GHz helical antenna and controls the absorbed power distribution. The 'ideal' power distribution required to achieve steady-state temperature uniformity over a given region has been calculated and a corresponding antenna trajectory programmed to approximate this pattern. Computer models, based on the solution of the bio-heat equation, have been implemented to allow various system parameters, such as antenna beam size, scan path and velocity profile, to be optimized. Experiments on a homogeneous muscle-equivalent phantom have shown that the scanning antenna system produces uniform temperature distributions over large areas of arbitrary shape. The addition of a thermal control system, based on temperature signal feedback, would enable 'real-time' modification of the power distribution and allow inhomogeneous and perfused tissue structures to be heated more uniformly.

Quantitative assessment of impedance tomography for temperature measurements in microwave hyperthermia

The objective of this study is a non-invasive assessment of the thermal dose in microwave hyperthermia. We intend to monitor the induced temperature rise via the change in the resistivity of body tissue, and hence control the microwave power during treatment. An initial feasibility study using electrical impedance tomography in vivo has indicated that a microwave induced temperature difference of a suitable magnitude can be mapped from a knowledge of the temperature coefficient of conductivity for tissue (typically 2% per degrees C). The accuracy of the currently employed reconstruction algorithm is assessed from data simulated by finite element prediction methods. A circular arrangement of electrodes surrounding a conductive sheet is used to evaluate the voltage distribution on the boundary of the sheet. A range of regions inside the circular field are chosen and the conductivity is changed uniformly by steps of 1% up to 10%. Images of these changes are produced. It is noticed that the algorithm underestimates the values of resistivity change for the small areas and overestimates the change for the larger areas. We are studying results for a variety of shapes of surface regions of the body that undergo resistivity change with microwave heating applied. Further work is necessary to account for three-dimensional current paths. Preliminary results are also presented of experimental investigations of the microwave-induced temperature rise in layers of carbon-loaded paper sheet.

The influence of tissue layering on microwave thermographic measurements

Non-invasive thermal imaging and temperature measurement by microwave radiometry has been investigated for medical diagnostic applications and monitoring hyperthermia treatment of cancer, in the context of heterogeneous body structure. The temperature measured by a radiometer is a function of the emission and propagation of microwaves in tissue and the receiving characteristics of the radiometric probe. Propagation of microwaves in lossy media was analysed by a spectral diffraction approach. Extension of this technique via a cascade transmission line model provides an efficient algorithm for predicting the field patterns of aperture antennas contacting multi-layered tissue. A coherent radiative transfer analysis was used to relate the field pattern of a radiating antenna to its receiving characteristics when used as a radiometer probe, leading to a method for simulating radiometric data. Measurements and simulations were used to assess the effect of overlying fat layers upon radiometer response to temperature hot spots in muscle-type media. Results suggest that dielectric layering in tissue greatly influences measured temperatures and should be accounted for in the interpretation of radiometric data.

A feasibility study of microwave thermographic mapping for use during hyperthermia treatment

A study to assess the possible use of a microwave radiometric system for tomographic thermal mapping during hyperthermia treatment has been examined using a computer model. Results indicate that as few as ten waveguide probes in contact with the body may be sufficient for spatial resolution of the heated region. A single probe microwave radiometer has been constructed and used to obtain scan data in a water phantom as an initial stage in the verification of the computer results.

Studies in burns: XIV, Heling in burn wounds treated with Ethyl Linoleate alone or in combination with selected topical antibacterial agents

Studies of the efficacy, in terms of burned wound healing, of a mixture of Ethyl Linoleate (ethyl 9-12 (cis, cis) octadecadienoate) with alpha-1-histidine, alpha-tocopherol, and TBHQ (hELate) was undertaken in 12 swine. The species was selected so as to study an animal with skin anatomy similar to the human. Statistically significantly greater healing occurred in 730 C/7sec contact burns (20% BSA) treated with hELate than in untreated burns in pigs. Further, there was no contracture noted in the hELate treated lesions, while marked contracture occurred in the untreated burns. Additionally, we noted that there was a proportional increase in weight gain amongst swine studied as their burn lesions epithelialized. In order to evaluate the compatibility of hELate with selected, currently-used topical antibacterial agents, 154 rabbits with 20% 730 C/7 sec contact burns were studied. The lipid was applied (0.01 ml/cm2 burn) at 1 hour postburning; the topical agent was applied at 2 hours post-burn and every 24-hours. All animals were washed once daily. hELate was applied only once. We found no statistical difference in the number of subjects healed or in the mortality between animals treated with hELate alone and those treated with the agent plus Gentamycin cream, Neosporin cream, and silver sulfadiazine 1% in Unibase USP (compounded at Medical College of Georgia specifically and only for this study.) We suggest that Ethyl Linoleate agent (hELate) may be used safely in combination with selected antibacterial substances. Further, these selected combinations seem to be non-toxic and appear to allow the calorie-saving and healing effects of the lipid to proceed unimpeded.

Studies in burns. XIII. Effects of a topical lipid on burned subjects and their wounds

We evaluated ethyl linoleate (ethyl, (9, 12)-cic, cis-octadecadienoate), a naturally occurring cutaneous water-holding lipid, for its water-holding metabolic, healing and toxic properties in groups of unburned and burned rabbits and its toxic potentials in this species and mice. The lipid appears to reduce evaporative water loss in full-thickness burned rabbits. Associated with this effect is a proportional and related lowering of metabolic heat production. The topical application of the lipid at any time after burn appears to be associated with a significant healing in lesions that, histologically at least, would be interpreted as fullthickness. The material is highly toxic if applied daily to mice or rabbits. The details of the toxic effect (s) are being studied. The commerical-grade material (75 percent pure) contains a derivative of ricinoleci acid and chronic exposure of the EL to air may result in the formation of peroxides and epoxides. These materials exert well-defined toxicity. The obvious potential uses of this agent in treating human burn lesions need not be emphasized, but it does need to be stated categorically that, at present, (Feb 1974), the toxicity has not been defined enough for use except in experiments.