Tag: nevin manimala

Surg Infect (Larchmt). 2023 Aug 2. doi: 10.1089/sur.2023.030. Online ahead of print.

ABSTRACT

Abstract Background: Herpes simplex virus encephalitis (HSVE) is a rare post-operative infection that can be fatal if treatment is delayed. Herpes simplex virus type 1 (HSV-1) is a more common cause of encephalitis than herpes simplex virus type 2 (HSV-2), however, a significant overlap exists. The goal of this project was to understand the frequency and trend of HSVE after neurosurgery through a case series at our institution and in the literature with a focus on comparing HSV-1 versus HSV-2. Patients and Methods: A literature review of all published cases and case series of HSVE after neurosurgery was performed. Descriptive statistics comparing HSV-1 and HSV-2 encephalitis were computed. Data on demographics, symptoms, surgery, treatment, immunosuppression, imaging findings, steroids, and mortality were collected. Results: We identified 55 total cases of HSVE post-neurosurgery. These included 28 cases of HSV-1, 10 cases of HSV-2, and 17 cases of HSV-unspecified encephalitis. There were no differences in age, gender, symptoms, surgery, or latency between surgery and symptom onset between HSV-1 and HSV-2. Mortality was higher with HSV-1 versus HSV-2 although not statistically significant. The primary surgical indication varied substantially between HSV-1 and HSV-2. Conclusions: Herpes simplex virus encephalitis is often overlooked in the setting of encephalitis after surgery. A high index of suspicion is needed to prevent a delay in treatment.

PMID:37527427 | DOI:10.1089/sur.2023.030

West J Emerg Med. 2023 Jul 10;24(4):786-792. doi: 10.5811/westjem.57862.

ABSTRACT

OBJECTIVE: Patients discharged from the hospital with diagnoses of myocardial infarction, congestive heart failure or acute exacerbation of chronic obstructive pulmonary disease (COPD) have high rates of readmission. We sought to quantify the impact of a community paramedicine (CP) intervention on hospital readmission and emergency department (ED) and clinic utilization for patients discharged with these conditions and to calculate the difference in healthcare costs.

METHODS: This was a prospective, observational cohort study with a matched historical control. The groups were matched for qualifying diagnosis, age, gender, and ZIP code. The intervention group received 1-2 home visits per week by a community paramedic for 30 days. We calculated the number of all-cause hospital readmissions and ED and clinic visits, and used descriptive statistics to compare cohorts.

RESULTS: Included in the study were 78 intervention patients and 78 controls. Compared to controls, fewer subjects in the CP cohort had experienced a readmission at 120 days (34.6% vs 64.1%, P < 0.001) and 210 days (43.6% vs 75.6%, P < 0.001) after discharge. At 210 days the CP cohort had 40.9% fewer total hospital admissions, saving 218 bed days and $410,428 in healthcare costs. The CP cohort had 40.7% fewer total ED visits.

CONCLUSION: Patients who received a post-hospital community paramedic intervention had fewer hospital readmissions and ED visits, which resulted in saving 218 bed days and decreasing healthcare costs by $410,428. Incorporation of a home CP intervention of 30 days in this patient population has the potential to benefit payors, hospitals, and patients.

PMID:37527389 | DOI:10.5811/westjem.57862

West J Emerg Med. 2023 Jun 30;24(4):685-692. doi: 10.5811/westjem.58965.

ABSTRACT

INTRODUCTION: Point-of-care ultrasound (POCUS) is commonly used in the emergency department (ED) as a rapid diagnostic tool. Emergency medicine (EM) has been an early adopter of POCUS with indications expanding over the last 10 years. While the literature describes widespread use among academic sites, there is little data on clinical POCUS utilization at non-academic EDs. We sought to describe community emergency physician (EP) use of POCUS by quantifying the number and type of studies performed, characteristics of the performing physician, and quality metrics.

METHODS: Prior to the study period, all EPs underwent a standardized training and credentialing program. A retrospective review of all POCUS studies across 11 non-academic EDs from October 1, 2018-September 30, 2020 was performed by fellowship-trained physicians, who identified physician, exam type, and residency graduation year. The studies were then cross-referenced with quality review reports that assessed image acquisition, image interpretation, and image labeling. We performed descriptive statistics.

RESULTS: During the study period, 5,099 POCUS studies were performed by 170 EPs. Exams most frequently performed were cardiac (24%), focused assessment of sonography in trauma (21.7%), and pregnancy (16.2%). Recent EM residency graduates (<10 years) were higher utilizers of POCUS with a group mean of 1.3 exams per 100 patients. Of the studies done, 86% had no quality issues.

CONCLUSION: Community POCUS demonstrates a heavy focus on core exams performed by recent EM residency graduates with minimal quality issues after a standardized training program. This study is the first to quantify actual community POCUS use in multiple EDs and may impact credentialing and skills maintenance requirements.

PMID:37527388 | DOI:10.5811/westjem.58965

Radiat Res. 2023 Aug 1. doi: 10.1667/RADE-22-00189.1. Online ahead of print.

ABSTRACT

In radiobiology, and throughout translational biology, synergy theories for multi-component agent mixtures use 1-agent dose-effect relations (DERs) to calculate baseline neither synergy nor antagonism mixture DERs. The most used synergy theory, simple effect additivity, is not self-consistent when curvilinear 1-agent DERs are involved, and many alternatives have been suggested. In this paper we present the mathematical aspects of a new alternative, generalized Loewe additivity (GLA). To the best of our knowledge, generalized Loewe additivity is the only synergy theory that can systematically handle mixtures of agents that are malstressors (tend to produce disease) with countermeasures – agents that oppose malstressors and ameliorate malstressor damage. In practice countermeasures are often very important, so generalized Loewe additivity is potentially far-reaching. Our paper is a proof-of-principle preliminary study. Unfortunately, generalized Loewe additivity’s scope is restricted, in various unwelcome but perhaps unavoidable ways. Our results illustrate its strengths and its weaknesses. One area where our methodology has potentially important applications is analyzing counter-measure mitigation of galactic cosmic ray damage to astronauts during interplanetary travel.

PMID:37527362 | DOI:10.1667/RADE-22-00189.1

Am J Forensic Med Pathol. 2023 Jul 31. doi: 10.1097/PAF.0000000000000859. Online ahead of print.

ABSTRACT

Collecting and reporting accurate disaster mortality data are critical to informing disaster response and recovery efforts. The National Association of Medical Examiners convened an ad hoc committee to provide recommendations for the documentation and certification of disaster-related deaths. This article provides definitions for disasters and direct, indirect, and partially attributable disaster-related deaths; discusses jurisdiction for disaster-related deaths; offers recommendations for medical examiners/coroners (ME/Cs) for indicating the involvement of the disaster on the death certificate; discusses the role of the ME/C and non-ME/C in documenting and certifying disaster-related deaths; identifies existing systems for helping to identify the role of disaster on the death certificate; and describes disaster-related deaths that may require amendments of death certificates. The recommendations provided in this article seek to increase ME/C’s understanding of disaster-related deaths and promote uniformity in how to document these deaths on the death certificate.

PMID:37527356 | DOI:10.1097/PAF.0000000000000859

IEEE Trans Neural Netw Learn Syst. 2023 Aug 1;PP. doi: 10.1109/TNNLS.2023.3293888. Online ahead of print.

ABSTRACT

Traditional support vector machines (SVMs) are fragile in the presence of outliers; even a single corrupt data point can arbitrarily alter the quality of the approximation. If even a small fraction of columns is corrupted, then classification performance will inevitably deteriorate. This article considers the problem of high-dimensional data classification, where a number of the columns are arbitrarily corrupted. An efficient Support Matrix Machine that simultaneously performs matrix Recovery (SSMRe) is proposed, i.e. feature selection and classification through joint minimization of l_2,1 (the nuclear norm of L ). The data are assumed to consist of a low-rank clean matrix plus a sparse noisy matrix. SSMRe works under incoherence and ambiguity conditions and is able to recover an intrinsic matrix of higher rank in the presence of data densely corrupted. The objective function is a spectral extension of the conventional elastic net; it combines the property of matrix recovery along with low rank and joint sparsity to deal with complex high-dimensional noisy data. Furthermore, SSMRe leverages structural information, as well as the intrinsic structure of data, avoiding the inevitable upper bound. Experimental results on different real-time applications, supported by the theoretical analysis and statistical testing, show significant gain for BCI, face recognition, and person identification datasets, especially in the presence of outliers, while preserving a reasonable number of support vectors.

PMID:37527325 | DOI:10.1109/TNNLS.2023.3293888

IEEE Trans Neural Netw Learn Syst. 2023 Aug 1;PP. doi: 10.1109/TNNLS.2023.3282785. Online ahead of print.

ABSTRACT

Canonical correlation analysis (CCA) is a correlation analysis technique that is widely used in statistics and the machine-learning community. However, the high complexity involved in the training process lays a heavy burden on the processing units and memory system, making CCA nearly impractical in large-scale data. To overcome this issue, a novel CCA method that tries to carry out analysis on the dataset in the Fourier domain is developed in this article. Appling Fourier transform on the data, we can convert the traditional eigenvector computation of CCA into finding some predefined discriminative Fourier bases that can be learned with only element-wise dot product and sum operations, without complex time-consuming calculations. As the eigenvalues come from the sum of individual sample products, they can be estimated in parallel. Besides, thanks to the data characteristic of pattern repeatability, the eigenvalues can be well estimated with partial samples. Accordingly, a progressive estimate scheme is proposed, in which the eigenvalues are estimated through feeding data batch by batch until the eigenvalues sequence is stable in order. As a result, the proposed method shows its characteristics of extraordinarily fast and memory efficiencies. Furthermore, we extend this idea to the nonlinear kernel and deep models and obtained satisfactory accuracy and extremely fast training time consumption as expected. An extensive discussion on the fast Fourier transform (FFT)-CCA is made in terms of time and memory efficiencies. Experimental results on several large-scale correlation datasets, such as MNIST8M, X-RAY MICROBEAM SPEECH, and Twitter Users Data, demonstrate the superiority of the proposed algorithm over state-of-the-art (SOTA) large-scale CCA methods, as our proposed method achieves almost same accuracy with the training time of our proposed method being 1000 times faster. This makes our proposed models best practice models for dealing with large-scale correlation datasets. The source code is available at https://github.com/Mrxuzhao/FFTCCA.

PMID:37527324 | DOI:10.1109/TNNLS.2023.3282785

IEEE Trans Med Imaging. 2023 Aug 1;PP. doi: 10.1109/TMI.2023.3300656. Online ahead of print.

ABSTRACT

The segmentation of blurred cell boundaries in cornea endothelium microscope images is challenging, which affects the clinical parameter estimation accuracy. Existing deep learning methods only consider pixel-wise classification accuracy and lack of utilization of cell structure knowledge. Therefore, the segmentation of the blurred cell boundary is discontinuous. This paper proposes a structural prior guided network (SPG-Net) for corneal endothelium cell segmentation. We first employ a hybrid transformer convolution backbone to capture more global context. Then, we use Feature Enhancement (FE) module to improve the representation ability of features and Local Affinity-based Feature Fusion (LAFF) module to propagate structural information among hierarchical features. Finally, we introduce the joint loss based on cross entropy and structure similarity index measure (SSIM) to supervise the training process under pixel and structure levels. We compare the SPG-Net with various state-of-the-art methods on four corneal endothelial datasets. The experiment results suggest that the SPG-Net can alleviate the problem of discontinuous cell boundary segmentation and balance the pixel-wise accuracy and structure preservation. We also evaluate the agreement of parameter estimation between ground truth and the prediction of SPG-Net. The statistical analysis results show a good agreement and correlation.

PMID:37527299 | DOI:10.1109/TMI.2023.3300656

PLoS One. 2023 Aug 1;18(8):e0289366. doi: 10.1371/journal.pone.0289366. eCollection 2023.

ABSTRACT

Evolutionary models are used to study the self-organisation of collective action, often incorporating population structure due to its ubiquitous presence and long-known impact on emerging phenomena. We investigate the evolution of multiplayer cooperation in mobile structured populations, where individuals move strategically on networks and interact with those they meet in groups of variable size. We find that the evolution of multiplayer cooperation primarily depends on the network topology and movement cost while using different stochastic update rules seldom influences evolutionary outcomes. Cooperation robustly co-evolves with movement on complete networks and structure has a partially detrimental effect on it. These findings contrast an established principle from evolutionary graph theory that cooperation can only emerge under some update rules and if the average degree is lower than the reward-to-cost ratio and the network far from complete. We find that group-dependent movement erases the locality of interactions, suppresses the impact of evolutionary structural viscosity on the fitness of individuals, and leads to assortative behaviour that is much more powerful than viscosity in promoting cooperation. We analyse the differences remaining between update rules through a comparison of evolutionary outcomes and fixation probabilities.

PMID:37527254 | DOI:10.1371/journal.pone.0289366

PLoS One. 2023 Aug 1;18(8):e0288744. doi: 10.1371/journal.pone.0288744. eCollection 2023.

ABSTRACT

PURPOSE: The purpose of this study is to evaluate the influences of gadolinium-based contrast agents, field-strength and different sequences on perfusion quantification in Phase-Resolved Functional Lung (PREFUL) MRI.

MATERIALS AND METHODS: Four cohorts of different subjects were imaged to analyze influences on the quantified perfusion maps: 1) at baseline and after 2 weeks to obtain the reproducibility (26 COPD patients), 2) before and after the administration of gadobutrol (11 COPD, 2 PAH and 1 asthma), 3) at 1.5T and 3T (12 healthy, 4 CF), and 4) with different acquisition sequences spoiled gradient echo (SPGR) and balanced steady-state free precession (bSSFP) (11 COPD, 7 healthy). Wilcoxon-signed rank test, Bland-Altman plots, voxelwise Pearson correlations, normalized histogram analyses with skewness and kurtosis and two-sample Kolmogorov-Smirnov tests were performed. P value ≤ 0.05 was considered statistically significant.

RESULTS: In all cohorts, linear correlations of the perfusion values were significant with correlation coefficients of at least 0.7 considering the entire lung (P<0.01). The reproducibility cohort revealed stable results with a similar distribution. In the gadolinium cohort, the quantified perfusion increased significantly (P<0.01), and no significant change was detected in the histogram analysis. In the field-strength cohort, no significant change of the quantified perfusion was shown, but a significant increase of skewness and kurtosis at 3T (P = 0.01). In the sequence cohort, the quantified perfusion decreased significantly in the bSSFP sequence (P<0.01) together with a significant decrease of skewness and kurtosis (P = 0.02). The field-strength and sequence cohorts had differing probability distribution in the two-sample Kolmogorov-Smirnov tests.

CONCLUSION: We observed a high susceptibility of perfusion quantification to gadolinium, field-strength or MRI sequence leading to distortion and deviation of the perfusion values. Future multicenter studies should strictly adhere to the identical study protocols to generate comparable results.

PMID:37527251 | DOI:10.1371/journal.pone.0288744