1,240 research outputs found
Two-Dimensional Intravascular Near-Infrared Fluorescence Molecular Imaging of Inflammation in Atherosclerosis and Stent-Induced Vascular Injury
ObjectivesThis study sought to develop a 2-dimensional (2D) intravascular near-infrared fluorescence (NIRF) imaging strategy for investigation of arterial inflammation in coronary-sized vessels.BackgroundMolecular imaging of arterial inflammation could provide new insights into the pathogenesis of acute myocardial infarction stemming from coronary atheromata and implanted stents. Presently, few high-resolution approaches can image inflammation in coronary-sized arteries in vivo.MethodsA new 2.9-F rotational, automated pullback 2D imaging catheter was engineered and optimized for 360° viewing intravascular NIRF imaging. In conjunction with the cysteine protease-activatable imaging reporter Prosense VM110 (VisEn Medical, Woburn, Massachusetts), intra-arterial 2D NIRF imaging was performed in rabbit aortas with atherosclerosis (n =10) or implanted coronary bare-metal stents (n = 10, 3.5-mm diameter, day 7 post-implantation). Intravascular ultrasound provided coregistered anatomical images of arteries. After sacrifice, specimens underwent ex vivo NIRF imaging, fluorescence microscopy, and histological and immunohistochemical analyses.ResultsImaging of coronary artery–scaled phantoms demonstrated 8-sector angular resolution and submillimeter axial resolution, nanomolar sensitivity to NIR fluorochromes, and modest NIRF light attenuation through blood. High-resolution NIRF images of vessel wall inflammation with signal-to-noise ratios >10 were obtained in real-time through blood, without flushing or occlusion. In atherosclerosis, 2D NIRF, intravascular ultrasound–NIRF fusion, microscopy, and immunoblotting studies provided insight into the spatial distribution of plaque protease activity. In stent-implanted vessels, real-time imaging illuminated an edge-based pattern of stent-induced arterial inflammation.ConclusionsA new 2D intravascular NIRF imaging strategy provides high-resolution in vivo spatial mapping of arterial inflammation in coronary-sized arteries and reveals increased inflammation-regulated cysteine protease activity in atheromata and stent-induced arterial injury
Generational research: between historical and sociological imaginations
This paper reflects on Julia Brannen’s contribution to the development of theory and methods for intergenerational research. The discussion is contextualised within a contemporary ‘turn to time’ within sociology, involving tensions and synergies between sociological and historical imagination. These questions are informed by a juxtaposition of Brannen’s four-generation study of family change and social historian Angela Davis’s exploration women and the family in England between 1945 and 2000. These two studies give rise to complementary findings, yet have distinctive orientations towards the status and treatment of sources, the role of geography in research design and limits of generalisatio
Neutrality of Molecules by the Pulsed Gas Flow Method
Contains an introduction and a description on one research project.F.L. Friedman Chai
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The genomic landscape of Ménière's disease: a path to endolymphatic hydrops
BackgroundMénière's disease (MD) is a disorder of the inner ear that causes episodic bouts of severe dizziness, roaring tinnitus, and fluctuating hearing loss. To date, no targeted therapy exists. As such, we have undertaken a large whole genome sequencing study on carefully phenotyped unilateral MD patients with the goal of gene/pathway discovery and a move towards targeted intervention. This study was a retrospective review of patients with a history of Ménière's disease. Genomic DNA, acquired from saliva samples, was purified and subjected to whole genome sequencing.ResultsStringent variant calling, performed on 511 samples passing quality checks, followed by gene-based filtering by recurrence and proximity in molecular interaction networks, led to 481 high priority MD genes. These high priority genes, including MPHOSPH8, MYO18A, TRIOBP, OTOGL, TNC, and MYO6, were previously implicated in hearing loss, balance, and cochlear function, and were significantly enriched in common variant studies of hearing loss. Validation in an independent MD cohort confirmed 82 recurrent genes. Pathway analysis pointed to cell-cell adhesion, extracellular matrix, and cellular energy maintenance as key mediators of MD. Furthermore, the MD-prioritized genes were highly expressed in human inner ear hair cells and dark/vestibular cells, and were differentially expressed in a mouse model of hearing loss.ConclusionBy enabling the development of model systems that may lead to targeted therapies and MD screening panels, the genes and variants identified in this study will inform diagnosis and treatment of MD
Circulating HPV DNA as a Biomarker for Pre-Invasive and Early Invasive Cervical Cancer: A Feasibility Study
BACKGROUND: High-risk HPV infection is responsible for >99% of cervix cancers (CC). In persistent infections that lead to cancer, the tumour breaches the basement membrane, releasing HPV-DNA into the bloodstream (cHPV-DNA). A next-generation sequencing assay (NGS) for detection of plasma HPV circulating DNA (cHPV-DNA) has demonstrated high sensitivity and specificity in patients with locally advanced cervix cancers. We hypothesised that cHPV-DNA is detectable in early invasive cervical cancers but not in pre-invasive lesions (CIN). METHODS: Blood samples were collected from patients with CIN (n = 52) and FIGO stage 1A-1B CC (n = 12) prior to treatment and at follow-up. DNA extraction from plasma, followed by NGS, was used for the detection of cHPV-DNA. RESULTS: None of the patients with pre-invasive lesions were positive for CHPV-DNA. In invasive tumours, plasma from one patient (10%) reached the threshold of positivity for cHPV-DNA in plasma. CONCLUSION: Low detection of cHPV-DNA in early CC may be explained by small tumour size, poorer access to lymphatics and circulation, and therefore little shedding of cHPV-DNA in plasma at detectable levels. The detection rate of cHPV-DNA in patients with early invasive cervix cancer using even the most sensitive of currently available technologies lacks adequate sensitivity for clinical utility
Canagliflozin retards age-related lesions in heart, kidney, liver, and adrenal gland in genetically heterogenous male mice.
Canagliflozin (Cana), a clinically important anti-diabetes drug, leads to a 14% increase in median lifespan and a 9% increase in the 90th percentile age when given to genetically heterogeneous male mice from 7 months of age, but does not increase lifespan in female mice. A histopathological study was conducted on 22-month-old mice to see if Cana retarded diverse forms of age-dependent pathology. This agent was found to diminish incidence or severity, in male mice only, of cardiomyopathy, glomerulonephropathy, arteriosclerosis, hepatic microvesicular cytoplasmic vacuolation (lipidosis), and adrenal cortical neoplasms. Protection against atrophy of the exocrine pancreas was seen in both males and females. Thus, the extension of lifespan in Cana-treated male mice, which is likely to reflect host- or tumor-mediated delay in lethal neoplasms, is accompanied by parallel retardation of lesions, in multiple tissues, that seldom if ever lead to death in these mice. Canagliflozin thus can be considered a drug that acts to slow the aging process and should be evaluated for potential protective effects against many other late-life conditions
The impact of induction and/or concurrent chemoradiotherapy on acute and late patient-reported symptoms in oropharyngeal cancer:Application of a mixed-model analysis of a prospective observational cohort registry
BACKGROUND The goal of this study was to comprehensively investigate the association of chemotherapy with trajectories of acute symptom development and late symptom recovery in patients with oropharyngeal cancer (OPC) by comparing symptom burden between induction chemotherapy followed by concurrent chemoradiotherapy (ICRT), concurrent chemo-radiotherapy (CRT), or radiotherapy (RT) alone.METHODS Among a registry of 717 patients with OPC, the 28-item patient-reported MD Anderson Symptom Inventory-Head and Neck Module (MDASI-HN) symptoms were collected prospectively at baseline, weekly during RT, and 1.5, 3 to 6, 12, and 18 to 24 months after RT. The effect of the treatment regimen (ICRT, CRT, and RT alone) was examined with mixed-model analyses for the acute and late period. In the CRT cohort, the chemotherapy agent relationship with symptoms was investigated.RESULTS Chemoradiation (ICRT/CRT) compared with RT alone resulted in significantly higher acute symptom scores in the majority of MDASI-HN symptoms (ie, 21 out of 28). No late symptom differences between treatment with or without chemotherapy were observed that were not attributable to ICRT. Nausea was lower for CRT with carboplatin than for CRT with cisplatin; cetuximab was associated with particularly higher scores for acute and late skin, mucositis, and 6 other symptoms. The addition of ICRT compared with CRT or RT alone was associated with a significant increase in numbness and shortness of breath.CONCLUSION The addition of chemotherapy to definitive RT for OPC patients was associated with significantly worse acute symptom outcomes compared with RT alone, which seems to attenuate in the late posttreatment period. Moreover, induction chemotherapy was specifically associated with worse numbness and shortness of breath during and after treatment.LAY SUMMARYChemotherapy is frequently used in addition to radiotherapy cancer treatment, yet the (added) effect on treatment-induced over time is not comprehensively investigatedThis study shows that chemotherapy adds to the symptom severity reported by patients, especially during treatment</p
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Phenotypic heterogeneity and genetic modification of P102L inherited prion disease in an international series
The largest kindred with inherited prion disease P102L, historically Gerstmann-Sträussler-Scheinker syndrome, originates from central England, with émigrés now resident in various parts of the English-speaking world. We have collected data from 84 patients in the large UK kindred and numerous small unrelated pedigrees to investigate phenotypic heterogeneity and modifying factors. This collection represents by far the largest series of P102L patients so far reported. Microsatellite and genealogical analyses of eight separate European kindreds support multiple distinct mutational events at a cytosine-phosphate diester-guanidine dinucleotide mutation hot spot. All of the smaller P102L kindreds were linked to polymorphic human prion protein gene codon 129M and were not connected by genealogy or microsatellite haplotype background to the large kindred or each other. While many present with classical Gerstmann-Sträussler-Scheinker syndrome, a slowly progressive cerebellar ataxia with later onset cognitive impairment, there is remarkable heterogeneity. A subset of patients present with prominent cognitive and psychiatric features and some have met diagnostic criteria for sporadic Creutzfeldt-Jakob disease. We show that polymorphic human prion protein gene codon 129 modifies age at onset: the earliest eight clinical onsets were all MM homozygotes and overall age at onset was 7 years earlier for MM compared with MV heterozygotes (P = 0.02). Unexpectedly, apolipoprotein E4 carriers have a delayed age of onset by 10 years (P = 0.02). We found a preponderance of female patients compared with males (54 females versus 30 males, P = 0.01), which probably relates to ascertainment bias. However, these modifiers had no impact on a semi-quantitative pathological phenotype in 10 autopsied patients. These data allow an appreciation of the range of clinical phenotype, modern imaging and molecular investigation and should inform genetic counselling of at-risk individuals, with the identification of two genetic modifiers
Localizing transcripts to single cells suggests an important role of uncultured deltaproteobacteria in the termite gut hydrogen economy
Identifying microbes responsible for particular environmental
functions is challenging, given that most environments contain
an uncultivated microbial diversity. Here we combined approaches
to identify bacteria expressing genes relevant to catabolite flow
and to locate these genes within their environment, in this case
the gut of a “lower,” wood-feeding termite. First, environmental
transcriptomics revealed that 2 of the 23 formate dehydrogenase
(FDH) genes known in the system accounted for slightly more than
one-half of environmental transcripts. FDH is an essential enzyme
of H_2 metabolism that is ultimately important for the assimilation
of lignocellulose-derived energy by the insect. Second, single-cell
PCR analysis revealed that two different bacterial types expressed
these two transcripts. The most commonly transcribed FDH in situ
is encoded by a previously unappreciated deltaproteobacterium,
whereas the other FDH is spirochetal. Third, PCR analysis of fractionated
gut contents demonstrated that these bacteria reside in
different spatial niches; the spirochete is free-swimming, whereas
the deltaproteobacterium associates with particulates. Fourth, the
deltaproteobacteria expressing FDH were localized to protozoa via
hybridization chain reaction-FISH, an approach for multiplexed,
spatial mapping of mRNA and rRNA targets. These results underscore
the importance of making direct vs. inference-based gene–
species associations, and have implications in higher termites, the
most successful termite lineage, in which protozoa have been lost
from the gut community. Contrary to expectations, in higher termites,
FDH genes related to those from the protozoan symbiont
dominate, whereas most others were absent, suggesting that a
successful gene variant can persist and flourish after a gut perturbation
alters a major environmental niche
Proton Image-guided Radiation Assignment for Therapeutic Escalation via Selection of locally advanced head and neck cancer patients [PIRATES]:A Phase I safety and feasibility trial of MRI-guided adaptive particle radiotherapy
Introduction: Radiation dose-escalation for head and neck cancer (HNC) patients aiming to improve cure rates is challenging due to the increased risk of unacceptable treatment-induced toxicities. With “Proton Image-guided Radiation Assignment for Therapeutic Escalation via Selection of locally advanced head and neck cancer patients” (PIRATES), we present a novel treatment approach that is designed to facilitate dose-escalation while minimizing the risk of dose-limiting toxicities for locally advanced HPV-negative HNC patients. The aim of this Phase I trial is to assess the safety & feasibility of PIRATES approach. Methods: The PIRATES protocol employs a multi-faceted dose-escalation approach to minimize the risk of dose-limiting toxicities (DLTs): 1) sparing surrounding normal tissue from extraneous dose with intensity-modulated proton therapy, 2) mid-treatment hybrid hyper-fractionation for radiobiologic normal tissue sparing; 3) Magnetic Resonance Imaging (MRI) guided mid-treatment boost volume adaptation, and 4) iso-effective restricted organ-at-risk dosing to mucosa and bone tissues. The time-to-event Bayesian optimal interval (TITE-BOIN) design is employed to address the challenge of the long DLT window of 6 months and find the maximum tolerated dose. The primary endpoint is unacceptable radiation-induced toxicities (Grade 4, mucositis, dermatitis, or Grade 3 myelopathy, osteoradionecrosis) occurring within 6 months following radiotherapy. The second endpoint is any grade 3 toxicity occurring in 3–6 months after radiation. Discussion: The PIRATES dose-escalation approach is designed to provide a safe avenue to intensify local treatment for HNC patients for whom therapy with conventional radiation dose levels is likely to fail. PIRATES aims to minimize the radiation damage to the tissue surrounding the tumor volume with the combination of proton therapy and adaptive radiotherapy and within the high dose tumor volume with hybrid hyper-fractionation and not boosting mucosal and bone tissues. Ultimately, if successful, PIRATES has the potential to safety increase local control rates in HNC patients with high loco-regional failure risk. Trial registration: ClinicalTrials.gov ID: NCT04870840; Registration date: May 4, 2021. Netherlands Trial Register ID: NL9603; Registration date: July 15, 2021
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