675 research outputs found

    Development of stainless cardiac histology of clinical biopsy samples with infrared spectroscopy

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    Cardiac diseases are the leading cause of mortality in the United States, accounting for every one in seven deaths. There are a large proportion of cardiac diseases that need histopathological examination by pathologists for a conclusive diagnosis, but this technique hasn’t been improved upon in the past decade. In this work, we have attempted to advance the current state of histology by developing stainless staining protocols using infrared spectroscopy. The current gold standard to identify cardiovascular complications such as ischemia, fibrosis, alcoholic cardiomyopathy and transplant rejection is biopsy followed by histology. This approach lacks in many aspects. Major challenges faced by pathologists are: addressing inter-observer variability and experimental variations in stain development, and developing approaches for in-situ histopathology. Specifically, in the case of cardiac transplants, regular monitoring of the transplant is required in order to ensure that the body accepts the transplant. This is done by collecting tissue biopsies at specific time intervals. The presence of lymphocytic infiltration and accompanying fibrosis is indicative of transplant rejection. A prompt clinical action is required if rejection is identified in the biopsy. Cardiac transplant patients can benefit from techniques that can identify lymphocytic infiltration and fibrosis with high accuracy, complementing current pathology practice and giving greater opportunity to pathologists to study complex cases. In the first part of this work, we used infrared spectroscopy coupled with supervised Bayesian classification to identify lymphocytic infiltration and fibrosis in the myocardium in endomyocardial biopsy samples. This classifier was robust and could be easily applied to identify lymphocytes in the tissue and to differentiate between fibrosis in endocardium with fibrosis in myocardium which stains similarly in hematoxylin and eosin stain (H&E). Repeated biopsy procedures can cause significant trauma to the patient, and often the surgeons require real time histopathology information of the tissue during surgeries. This cannot be accomplished by traditional histology where the tissue sample needs to be excised, sectioned and stained for analysis. Since infrared spectroscopy in stainless, probe-based instruments can be developed to provide detection in-situ but were earlier limited by the speed of imaging using Fourier Transform infrared spectrometers. The problem of speed can be overcome by using quantum cascade laser-based discrete frequency infrared (DFIR) imaging instruments. In the second part of this work, we analyzed data collected on recently developed discrete frequency instruments and compared it to data collected on FT-IR imaging instruments. This was done by unsupervised data clustering to observe histological classes in both types of data. After establishing that the data collected in DFIR mode retained spectral differences between the histological classes to enable their differentiation, in part three of this work we have done extensive analysis of classification approaches that can be applied to the DFIR data. This study will be relevant to many of the previously built Bayesian classification models that need to be evaluated for their applicability on data collected in discrete frequency mode. In addition, we identified specific spectral features that could be used to differentiate between fibrosis and normal tissue in cardiac biopsy samples computationally at high speed using discrete frequency approach. This can give way to utilization of this model in fiber optic probe-based technology for on-site detection of fibrosis in patients

    Quantitative chemical imaging: A top-down systems pathology approach to predict colon cancer patient survival

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    Colon cancer is the second deadliest cancer, affecting the quality of life in older patients. Prognosis is useful in developing an informed disease management strategy, which can improve mortality as well as patient comfort. Morphometric assessment provides diagnosis, grade, and stage information. However, it is subjective, requires multi-step sample processing, and annotations by pathologists. In addition, morphometric techniques offer minimal molecular information that can be crucial in determining prognosis. The interaction of the tumor with its surrounding stroma, comprised of several biomolecular factors and cells is a critical determinant of the behavior of the disease. To evaluate this interaction objectively, we need biomolecular profiling in spatially specific context. In this work, we achieved this by analyzing tissue microarrays using infrared spectroscopic imaging. We developed supervised classification algorithms that were used to reliably segment colon tissue into histological components, including differentiation of normal and desmoplastic stroma. Thus, infrared spectroscopic imaging enabled us to map the stromal changes around the tumor. This supervised classification achieved >0.90 area under the curve of the receiver operating characteristic curve for pixel level classification. Using these maps, we sought to define evaluation criteria to assess the segmented colon images to determine prognosis. We measured the interaction of tumor with the surrounding stroma containing activated fibroblast in the form of mathematical functions that took into account the structure of tumor and the prevalence of reactive stroma. Using these functions, we found that the interaction effect of large tumor size in the presence of a high density of activated fibroblasts provided patients with worse outcome. The overall 6-year probability of survival in patient groups that were classified as “low-risk” was 0.73 whereas in patients that were “high-risk” was 0.54 at p-value <0.0003. Remarkably, the risk score defined in this work was independent of patient risk assessed by stage and grade of the tumor. Thus, objective evaluation of prognosis, which adds to the current clinical regimen, was achieved by a completely automated analysis of unstained patient tissue to determine the risk of 6-year death. In this work, we demonstrate that quantitative chemical imaging using infrared spectroscopic imaging is an effective method to measure tumor-tumor microenvironment interactions. As a top-down systems pathology approach, our work integrated morphometry based spatial constraints and biochemistry based stromal changes to identify markers that gave us mechanistic insights into the tumor behavior. Our work shows that while the tumor microenvironment changes are prognostic, an interaction model that takes into account both the extent of microenvironment modifications, as well as the tumor morphology, is a better predictor of prognosis. Finally, we also developed automated tumor grade determination using deep learning based infrared image analysis. Thus, the computational models developed in this work provide an objective, processing-free and automated way to predict tumor behavior

    Mechanism of Occurrence of Photonic Band Gap

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    24 Hours chronomics of ambulatory blood pressure and its relation with circadian rhythm of 6-sulfatoxy melatonin in night shift health care workers

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    Background: Night shift workers have altered circadian pattern of blood pressure/heart rate and hormones like melatonin and cortisol. Due to this variation, night shift worker suffers from various cardiovascular disorders and hormonal disturbances.Methods: The Present study was aimed to investigate the effects of rotating night shift on 24 hours chronomics of BP/HR and its relation with 6-sulfatoxy melatonin levels. 62 healthy nursing professionals, aged 20-40 year, performing day and night shift duties were recruited. Each month scheduled to continuous 9 days night shift (12 hours in regular 9 nights, from 20:00 to 08:00); after 9 days night shift they perform remaining duties in day shift and 4 days off in each month.Results: Ambulatory BP and HR were recorded at every 30 min intervals in day time and each hour in night time synchronically with circadian pattern of 6 sulfatoxy melatonin during shift duties. Highly Significant difference was found in double amplitude (2DA) of blood pressure between night and day shift (p<0.001). In night shift, hyperbaric index (HBI) of mean systolic blood pressure was found to be increased at 00-03 am (midnight) while during day shift, peak was found at 06-09 am. Peak melatonin was to be found in early morning as compared to mid night in both the shift.Conclusions: The present study concluded that the desynchronization was appeared during night shift and entrainment of circadian rhythm in the day shift.

    DMPA provision in PSS clinics in Uttar Pradesh: Costs and prices

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    The injectable contraceptive DMPA was introduced in the private sector in India in 1993, contingent on completion of a post-marketing surveillance study of users. The commercial price of a dose of DMPA is about Rs. 150-180, exclusive of the fees of the medical provider. This price puts it beyond the reach of most Parivar Seva Sanstha (PSS) clients in need of safe and effective family planning (FP) services in Uttar Pradesh. Since April 1996, an experiment has been underway with three PSS clinics in Uttar Pradesh to study the effect of price on demand for DMPA. The study seeks to better understand the issues of service delivery, client profile and the price at which the service can be offered in a sustainable way. Since April 1996, PSS has charged clients selecting DMPA Rs. 50 in Agra, Rs. 100 in Lucknow, and the product is offered free in Varanasi. All other PSS clinics in India offer the product at Rs. 50. This cost analysis has two main objectives: to estimate the cost of providing DMPA services at three clinics in Uttar Pradesh and to analyze the price at which DMPA services can be sustainably offered given the cost structure at each clinic

    Minimal information for studies of extracellular vesicles 2018 (MISEV2018):a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

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    The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points

    Measurement of inclusive and differential cross sections for single top quark production in association with a W boson in proton-proton collisions at s \sqrt{s} = 13 TeV

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    Measurements of the inclusive and normalised differential cross sections are presented for the production of single top quarks in association with a W boson in proton-proton collisions at a centre-of-mass energy of 13 TeV. The data used were recorded with the CMS detector at the LHC during 2016-2018, and correspond to an integrated luminosity of 138 fb−1^{−1}. Events containing one electron and one muon in the final state are analysed. For the inclusive measurement, a multivariate discriminant, exploiting the kinematic properties of the events is used to separate the signal from the dominant ttˉt\bar{t} background. A cross section of 79.2 ± 0.9 (stat) −8.0+7.7^{+7.7}_{−8.0} (syst) ± 1.2 (lumi) pb is obtained, consistent with the predictions of the standard model. For the differential measurements, a fiducial region is defined according to the detector acceptance, and the requirement of exactly one jet coming from the fragmentation of a bottom quark. The resulting distributions are unfolded to particle level and agree with the predictions at next-to-leading order in perturbative quantum chromodynamics

    Search for long-lived particles decaying to a pair of muons in proton-proton collisions at s \sqrt{s} = 13 TeV

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    An inclusive search for long-lived exotic particles decaying to a pair of muons is presented. The search uses data collected by the CMS experiment at the CERN LHC in proton-proton collisions at s√ = 13 TeV in 2016 and 2018 and corresponding to an integrated luminosity of 97.6 fb−1. The experimental signature is a pair of oppositely charged muons originating from a common secondary vertex spatially separated from the pp interaction point by distances ranging from several hundred ÎŒm to several meters. The results are interpreted in the frameworks of the hidden Abelian Higgs model, in which the Higgs boson decays to a pair of long-lived dark photons ZD, and of a simplified model, in which long-lived particles are produced in decays of an exotic heavy neutral scalar boson. For the hidden Abelian Higgs model with m(ZD) greater than 20 GeV and less than half the mass of the Higgs boson, they provide the best limits to date on the branching fraction of the Higgs boson to dark photons for cτ(ZD) (varying with m(ZD)) between 0.03 and ≈0.5 mm, and above ≈0.5 m. Our results also yield the best constraints on long-lived particles with masses larger than 10 GeV produced in decays of an exotic scalar boson heavier than the Higgs boson and decaying to a pair of muons

    Observation of the Rare Decay of the η Meson to Four Muons

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    A search for the rare η→Ό+Ό−Ό+Ό− double-Dalitz decay is performed using a sample of proton-proton collisions, collected by the CMS experiment at the CERN LHC with high-rate muon triggers during 2017 and 2018 and corresponding to an integrated luminosity of 101  fb−1. A signal having a statistical significance well in excess of 5 standard deviations is observed. Using the η→Ό+Ό− decay as normalization, the branching fraction B(η→Ό+Ό−Ό+Ό−)=[5.0±0.8(stat)±0.7(syst)±0.7(B2ÎŒ)]×10−9 is measured, where the last term is the uncertainty in the normalization channel branching fraction. This work achieves an improved precision of over 5 orders of magnitude compared to previous results, leading to the first measurement of this branching fraction, which is found to agree with theoretical predictions

    Search for invisible decays of the Higgs boson produced via vector boson fusion in proton-proton collisions at s\sqrt{s} = 13 TeV

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    A search for invisible decays of the Higgs boson produced via vector boson fusion (VBF) has been performed with 101  fb−1^{-1} of proton-proton collisions delivered by the LHC at s\sqrt{s} =13  TeV and collected by the CMS detector in 2017 and 2018. The sensitivity to the VBF production mechanism is enhanced by constructing two analysis categories, one based on missing transverse momentum and a second based on the properties of jets. In addition to control regions with Z and W boson candidate events, a highly populated control region, based on the production of a photon in association with jets, is used to constrain the dominant irreducible background from the invisible decay of a Z boson produced in association with jets. The results of this search are combined with all previous measurements in the VBF topology, based on data collected in 2012 (at s\sqrt{s} =8  TeV), 2015, and 2016, corresponding to integrated luminosities of 19.7, 2.3, and 36.3  fb−1^{-1}, respectively. The observed (expected) upper limit on the invisible branching fraction of the Higgs boson is found to be 0.18 (0.10) at the 95% confidence level, assuming the standard model production cross section. The results are also interpreted in the context of Higgs-portal models
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