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Background: Junctional ectopic tachycardia (JET) is a prevalent life-threatening arrhythmia in children with congenital heart disease. It has a marked resemblance to normal sinus rhythm, often leading to delay in diagnosis and management. Objective: The study sought to develop a novel multimodal automated arrhythmia detection tool that outperforms existing JET detection tools. Methods: This is a cohort study performed on 40 patients with congenital heart disease at Texas Children's Hospital. Electrocardiogram and central venous pressure waveform data produced by bedside monitors are captured by the Sickbay platform. Convolutional neural networks (CNNs) were trained to classify each heartbeat as either normal sinus rhythm or JET based only on raw electrocardiogram signals. Results: Our best model improved the area under the curve from 0.948 to 0.952 and the true positive rate at 5% false positive rate from 71.8% to 80.6%. Using a 3-model ensemble further improved the area under the curve to 0.953 and the true positive rate at 5% false positive rate to 85.2%. Results on a subset of data show that adding central venous pressure can significantly improve area under the receiver-operating characteristic curve from 0.646 to 0.825. Conclusion: This study validates the efficacy of deep neural networks to notably improve JET detection accuracy. We have built a performant and reliable model that can be used to create a bedside alarm that diagnoses JET, allowing for precise diagnosis of this life-threatening postoperative arrhythmia and prompt intervention. Future validation of the model in a larger cohort is needed.
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BACKGROUND: Hiatal hernia repair (HHR) performed concurrently with vertical sleeve gastrectomy (VSG) has been shown to improve postoperative gastroesophageal reflux disease (GERD). However, data on the optimal extent of esophageal mobilization during repair are lacking. Mobilization techniques for HHR during VSG include partial (PM) or full (FM) mobilization of the esophagus. We hypothesize that patients who undergo full mobilization will be less likely to develop postoperative reflux. METHODS: A single-institution retrospective review of all patients who underwent a VSG with a HHR between 2014 and 2021 was conducted. The primary outcome was postoperative reflux symptoms defined by diagnosis in the medical record, utilization of anti-reflux medications, and GERD health-related quality of life (GERD-HRQL) scores obtained via patient surveys. RESULTS: There were 190 patients included with 80 patients (42.1%) undergoing PM and 110 (57.9%) undergoing FM. Rates of preoperative reflux were similar between the two groups (47.5% vs. 51.8%; p = 0.55). During the GERD-HRQL survey, there were 114 patients (60.0%) contacted with a participation rate of 91.2% (104 patients). Patients with preoperative reflux who underwent PM were found to have a higher rate of reported postoperative reflux (90.0% vs. 62.5%; p = 0.03) and higher GERD-HRQL scores (16.40 ± 9.95 vs. 10.84 ± 9.01; p = 0.04). Patients without preoperative reflux did not have a significant difference in reported reflux (55.0% vs. 51.7%; p = 0.82) or GERD-HRQL scores (12.35 ± 14.14 vs. 9.93 ± 9.46; p = 0.25). CONCLUSION: Our study found that postoperative GERD was higher in patients with preexisting reflux who underwent partial esophageal mobilization during concurrent hiatal hernia repair with vertical sleeve gastrectomy. In patients without preoperative GERD, our data suggest that postoperative reflux symptoms are not dependent on the extent of esophageal mobilization during hiatal hernia repair with vertical sleeve gastrectomy.
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Recording and analysis of neural activity is often biased toward detecting sparse subsets of highly active neurons, masking important signals carried in low magnitude and variable responses. To investigate the contribution of seemingly noisy activity to odor encoding, we used mesoscale calcium imaging from mice of both sexes to record odor responses from the dorsal surface of bilateral olfactory bulbs (OBs). The outer layer of the mouse OB is comprised of dendrites organized into discrete "glomeruli", which are defined by odor receptor-specific sensory neuron input. We extracted activity from a large population of glomeruli and used logistic regression to classify odors from individual trials with high accuracy. We then used add-in and drop-out analyses to determine subsets of glomeruli necessary and sufficient for odor classification. Classifiers successfully predicted odor identity even after excluding sparse, highly active glomeruli, indicating that odor information is redundantly represented across a large population of glomeruli. Additionally, we found that Random Forest feature selection informed by Gini Inequality (RFGI) reliably ranked glomeruli by their contribution to overall odor classification. RFGI provided a measure of "feature importance" for each glomerulus that correlated with intuitive features like response magnitude. Finally, in agreement with previous work, we found that odor information persists in glomerular activity after odor offset. Together, our findings support a model of olfactory bulb odor coding where sparse activity is sufficient for odor identification, but information is widely, redundantly available across a large population of glomeruli, with each glomerulus representing information about more than one odor.Significance statement This study leverages meso-scale imaging and machine learning to investigate how odor information is first represented in the brain. Typically, recordings of neuronal activity focus on active individual cells, potentially overlooking broader variations in neuronal responses across populations. Our results demonstrate that a considerable amount of olfactory information is redundantly distributed across a large proportion of olfactory bulb glomeruli. Even after excluding a majority of glomeruli, odor identification remained possible. These findings indicate that, although a few glomeruli are sufficient for odor recognition, an abundance of additional information is represented across a broad population. Understanding how the brain manages redundant olfactory information will shed light on its adaptive mechanisms for navigating diverse real-world circumstances and responding to fluctuating internal states.
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Depression is a common illness, affecting >264 million people worldwide. According to the literature, depression patients have baseline subclinical inflammation. The immunomodulatory effects of antidepressants, such as selective serotonin reuptake inhibitors (SSRIs), are largely unclear and poorly understood. Using evidence-based medicine, this study aimed to determine the immunomodulatory effects of SSRIs by assessing changes in immunomodulatory markers following SSRI treatment. Using the PubMed website, a literature search was conducted with various terminologies related to the treatment of depression and various markers of inflammation. Out of 387 retrieved articles, after critical appraisal and screening based on inclusion and exclusion criteria, 17 were selected. Qualitative synthesis and quantitative analysis were carried out. RevMan 5 software was used to synthesize and evaluate the data. Microsoft Word and Excel (Microsoft Corporation, Redmond, Washington, United States) were used for generating tables and figures. We extracted data from a total of 839 patients in 17 studies. A highly significant reduction in interleukins-6 (IL-6) (standardised mean difference (SMD) = 1.32 (95% confidence interval (CI): 0.58, 2.06), Z = 3.48, P = 0.0005), a significant reduction in tumor necrosis factor-alpha (TNF-α) (SMD = 1.29 (95% CI: 0.19, 2.39), Z = 2.30, P = 0.02) but no change in overall C-reactive protein (CRP) (SMD = 0.40 (95% CI: -0.26, 1.07), Z = 1.19, P = 0.23) levels were observed by using the random-effects model. There was substantial heterogeneity found between the studies. SSRIs have an immunomodulatory effect in patients with depression by significantly reducing the peripheral pro-inflammatory cytokine markers of IL-6 and TNF-α, which may contribute to ameliorating the response to antidepressant drug treatment. In contrast, no effects of SSRIs on acute-phase protein CRP were found.
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Adversarial attacks are still a significant challenge for neural networks. Recent efforts have shown that adversarial perturbations typically contain high-frequency features, but the root cause of this phenomenon remains unknown. Inspired by theoretical work on linear convolutional models, we hypothesize that translational symmetry in convolutional operations together with localized kernels implicitly bias the learning of high-frequency features, and that this is one of the main causes of high frequency adversarial examples. To test this hypothesis, we analyzed the impact of different choices of linear and non-linear architectures on the implicit bias of the learned features and adversarial perturbations, in spatial and frequency domains. We find that, independently of the training dataset, convolutional operations have higher frequency adversarial attacks compared to other architectural parameterizations, and that this phenomenon is exacerbated with stronger locality of the kernel (kernel size) end depth of the model. The explanation for the kernel size dependence involves the Fourier Uncertainty Principle: a spatially-limited filter (local kernel in the space domain) cannot also be frequency-limited (local in the frequency domain). Using larger convolution kernel sizes or avoiding convolutions (e.g., by using Vision Transformers or MLP-style architectures) significantly reduces this high-frequency bias. Looking forward, our work strongly suggests that understanding and controlling the implicit bias of architectures will be essential for achieving adversarial robustness.
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Recent advances in surgical neuromodulation have enabled chronic and continuous intracranial monitoring during everyday life. We used this opportunity to identify neural predictors of clinical state in 12 individuals with treatment-resistant obsessive-compulsive disorder (OCD) receiving deep brain stimulation (DBS) therapy ( NCT05915741 ). We developed our neurobehavioral models based on continuous neural recordings in the region of the ventral striatum in an initial cohort of five patients and tested and validated them in a held-out cohort of seven additional patients. Before DBS activation, in the most symptomatic state, theta/alpha (9 Hz) power evidenced a prominent circadian pattern and a high degree of predictability. In patients with persistent symptoms (non-responders), predictability of the neural data remained consistently high. On the other hand, in patients who improved symptomatically (responders), predictability of the neural data was significantly diminished. This neural feature accurately classified clinical status even in patients with limited duration recordings, indicating generalizability that could facilitate therapeutic decision-making.
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BACKGROUND: Patients undergoing sleeve gastrectomy (SG) experience transformative changes in eating-related experiences that include eating-related symptoms, emotions, and habits. Long-term assessment of these endpoints with rigorous patient-reported outcome measures (PROMs) is limited. We assessed patients undergoing SG with the Body-Q Eating Module PROMs. METHODS: All patients evaluated at the Emory Bariatric Center were given the Body-Q Eating Modules questionnaire at preoperative/postoperative clinic visits. Rasch scores and prevalence of relevant endpoints were assessed across six time-points of interest: preoperatively, post-operative months 0-6, 7-12, 12-24, 24-36, and over 36. Student's t-test and Chi-square test were used for analysis. RESULTS: Overall, 1,352 questionnaires were completed pre-operatively and 493 postoperatively. Survey compliance was 81%. Compared to the pre-operative group, the post-operative group had lower BMI (39.7 vs. 46.4, p < 0.001) and higher age (46.3 vs. 44.9, p = 0.019). Beginning one year after SG, patients experience more frequent eating-related pain, nausea and constipation compared to pre-operative baseline (p < 0.05). They also more frequently experience eating-related regurgitation and dumping syndrome-related symptoms beginning post-operative year two (p < 0.05). In the first year after SG, patients more rarely feel eating-related embarrassment, guilt, and disappointment compared to pre-operative baseline (p < 0.05). These improvements disappear one year after SG, after which patients more frequently experience feeling out of control, unhappy, like a failure, disappointed, and guilty (p < 0.05). In the first year after SG, patients experience an increased frequency in positive eating behaviors (ate healthy foods, showed self-control, stopped before full; (p < 0.05). Only two eating-related behavior improvements persist long-term: feeling in control and eating the right amount (p < 0.05). CONCLUSIONS: Patients undergoing SG may experience more frequent eating-related symptoms, distress, and behavior in the long-term. These findings can enhance the pre-operative informed consent and guide development of a more tailored approach to postoperative clinical management such as more frequent visits with the dietician.
Subject(s)
Gastrectomy , Obesity, Morbid , Patient Reported Outcome Measures , Humans , Gastrectomy/methods , Gastrectomy/psychology , Female , Male , Cross-Sectional Studies , Adult , Middle Aged , Obesity, Morbid/surgery , Obesity, Morbid/psychology , Feeding Behavior/psychology , Surveys and Questionnaires , Bariatric Surgery/psychology , Feeding and Eating Disorders/psychologyABSTRACT
INTRODUCTION: Pathway innovation using smartphone otoscopy and tablet-based audiometry technologies to deliver ear and hearing services via trained audiologists may improve efficiency of the service. An ENT-integrated-community-ear service (ENTICES-combining community audiology management, remote ENT review and novel technologies) was piloted. We aimed to assess the efficiency and safety of ENTICES. METHOD: ENTICES was a community-based and audiologist-led pathway. Patients with otological symptoms were self-referred to this service. Smartphone otoscopy and tablet-based audiograms were performed. Two otologists reviewed all decisions made in the community by audiologists based on video-otoscopy, hearing tests and chart reviews. Data on the first 50 consecutive new patients attending either consultant-led hospital otology clinics (HOC), audiologist-led hospital advanced audiology diagnostics (AAD) or ENTICES clinics were collected between 1 August 2021 and 31 December 2021. Data were collected through chart reviews and questionnaires to compare the three pathways with respect to efficiency, patient satisfaction, technology utility and safety. RESULTS: No audiology-led ENTICES decisions were amended by hospital otologists following remote review. Remote review of video-otoscopy with history was sufficient for a diagnosis in 80% of cases. Adding hearing tests and standardised history increased the diagnostic yield to 98%. Patient satisfaction scores showed 100% service recommendation. The cost per patient, per visit, was £83.36, £99.07 and £69.72 for AAD, HOC or ENTICES, respectively. CONCLUSION: ENTICES provides a safe ear and hearing service that patients rated highly. Thirty-two per cent of hospital otology patients were eligible for this service. For those patients, ENTICES is 20% more cost-effective and can reduce the number of clinic visits by up to 60% compared with HOC.
Subject(s)
Otolaryngology , Telemedicine , Humans , Pilot Projects , Male , Female , Middle Aged , Adult , Otoscopy/methods , Aged , Ear Diseases/diagnosis , Ear Diseases/therapy , Patient Satisfaction , Audiometry , Adolescent , Referral and ConsultationABSTRACT
OBJECTIVE: Tonsillectomy is a common procedure performed nationally. The personal protective equipment and surgical gowning practices used during this procedure vary widely. We compiled a survey of ENT specialists to gain a national opinion about gowning in tonsillectomy with the aim of determining whether we could make it more environmentally friendly whilst maintaining the highest safety standards. METHOD: We developed a nine-question survey that was piloted prior to final implementation. The questionnaire was sent to senior registrars and consultant otolaryngologists in the UK. RESULTS: The survey was completed by a total of 63 ENT specialists. It was found that 82.54 per cent of clinicians would consider wearing a reusable gown that would be sterilised between each procedure. CONCLUSION: Our survey suggests most ENT clinicians would consider using a more environmentally friendly surgical gown and some may even consider wearing no gown at all, although many are understandably concerned about the transmission of infection or blood splatter.
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Noncoding DNA undergoes widespread context-dependent transcription to produce noncoding RNAs. In recent decades, tremendous advances in genomics and transcriptomics have revealed important regulatory roles for noncoding DNA elements and the RNAs that they produce. Enhancers are one such element that are well-established drivers of gene expression changes in response to a variety of factors such as external stimuli, cellular responses, developmental cues, and disease states. They are known to act at long distances, interact with multiple target gene loci simultaneously, synergize with other enhancers, and associate with dynamic chromatin architectures to form a complex regulatory network. Recent advances in enhancer biology have revealed that upon activation, enhancers transcribe long noncoding RNAs, known as enhancer RNAs (eRNAs), that have been shown to play important roles in enhancer-mediated gene regulation and chromatin-modifying activities. In the brain, enhancer dysregulation and eRNA transcription has been reported in numerous disorders from acute injuries to chronic neurodegeneration. Because this is an emerging area, a comprehensive understanding of eRNA function has not yet been achieved in brain disorders; however, the findings to date have illuminated a role for eRNAs in activity-driven gene expression and phenotypic outcomes. In this review, we highlight the breadth of the current literature on eRNA biology in brain health and disease and discuss the challenges as well as focus areas and strategies for future in-depth research on eRNAs in brain health and disease.
Subject(s)
Brain Diseases , RNA, Long Noncoding , Humans , Enhancer RNAs , Enhancer Elements, Genetic , Gene Expression Regulation , Chromatin/genetics , RNA, Long Noncoding/genetics , Brain Diseases/genetics , DNA , Transcription, GeneticABSTRACT
AIM OF THE STUDY: Multiple ring-enhancing lesions are commonly experienced group of brain pathologies which we come across in day-to-day practice. Clinical symptoms in these lesions are quite non-specific, and hence, it is difficult to reach a final diagnosis. However, these lesions have a varied group of differential diagnosis and it is sometimes difficult to have an accurate diagnosis on conventional MRI. This article was written with the objective of discussing the demographical study and etiology, clinical diagnosis and management for these patients. MATERIALS AND METHODS: It is a prospective study carried out at the Department of Neurosurgery, Dr. D Y Patil Medical College and Hospital, Pune, from September 2019 to August 2022 and included 50 patients who presented to us multiple ring-enhancing brain lesions. RESULTS: In our study, 50 patients between age (1-70 years) with multiple ring-enhancing lesions were analyzed. Majority of the patients were between age group 30-39 years. Males (76%) were majority in our study than females (24%). Most common pathology was primary neoplasm (glioma) and metastasis, followed by nine patients of pyogenic abscess and tuberculosis each. Neurocysticercosis was seen in eight patients and three patients were diagnosed with CNS lymphoma. Most of our patients presented with headache (38 patients) and a subset of patients had associated seizures (28 patients). Two patients with primary neoplasm were diagnosed to have WHO grade 3 glioma and seven patients were diagnosed to have WHO grade 4 glioma. Glioblastoma multiforme presented as multifocal and multicentric lesions. Among the patients with primary neoplasm, three patients underwent stereotactic biopsy for diagnosis and the rest of seven patients underwent maximum safe resection followed by chemotherapy and radiotherapy. Ten patients were diagnosed with metastatic lesions, among them six patients underwent stereotactic biopsy for histopathological diagnosis and immunohistochemistry, and rest of the patients were managed on the basis of the primary lesion. Five patients were immune-compromised, among them two patients presented with abscess and three patients presented with primary neoplastic lesion. Thirty-six patients underwent biopsy, among them seven patients underwent frameless, seven patients underwent frame stereotactic biopsy, and the rest 22 patients underwent excision biopsy. CONCLUSION: Multiple ring-enhancing lesions of brain pose a challenge in terms of achieving an accurate diagnosis and planning further treatment. It is of utmost importance to have a diagnosis in mind based on radiological investigations, so that surgical intervention can be planned accordingly be it by invasive or minimal invasive techniques. An idea toward the diagnosis also helps in prognosticating these patients which could avoid costly whole-body scans and unnecessary surgical intervention.
Subject(s)
Brain Neoplasms , Glioma , Male , Female , Humans , Infant , Child, Preschool , Child , Adolescent , Young Adult , Adult , Middle Aged , Aged , Brain Neoplasms/diagnosis , Brain Neoplasms/therapy , Brain Neoplasms/pathology , Abscess , Prospective Studies , Tertiary Healthcare , India , Glioma/pathology , Biopsy/methodsABSTRACT
A 46-year-old female came to neurosurgery outpatient department with sudden onset of drooping of RE upper eyelid and restriction of movements in adduction, depression and elevation in right eye. Patient was a known case of diabetes mellitus whose blood sugar levels were deranged. On examination, patient was diagnosed pituitary macroadenoma. Patient was treated for her uncontrolled diabetes mellitus following which she had underwent transsphenoidal pituitary macroadenoma removal. On treatment, patient's ptosis had subsided and restriction of movement has resolved.
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Despite the common focus of gait in rehabilitation, there are few tools that allow quantitatively characterizing gait in the clinic. We recently described an algorithm, trained on a large dataset from our clinical gait analysis laboratory, which produces accurate cycle-by-cycle estimates of spatiotemporal gait parameters including step timing and walking velocity. Here, we demonstrate this system generalizes well to clinical care with a validation study on prosthetic users seen in therapy and outpatient clinics. Specifically, estimated walking velocity was similar to annotated 10-m walking velocities, and cadence and foot contact times closely mirrored our wearable sensor measurements. Additionally, we found that a 2D keypoint detector pretrained on largely able-bodied individuals struggles to localize prosthetic joints, particularly for those individuals with more proximal or bilateral amputations, but after training a prosthetic-specific joint detector video-based gait analysis also works on these individuals. Further work is required to validate the other outputs from our algorithm including sagittal plane joint angles and step length. Code for the gait transformer and the trained weights are available at https://github.com/peabody124/GaitTransformer .
Subject(s)
Artificial Limbs , Gait Analysis , Humans , Gait , Walking , Lower Extremity , Biomechanical PhenomenaABSTRACT
Cholangiocarcinoma (CCA) is a deadly and heterogeneous type of cancer characterized by a spectrum of epidemiologic associations as well as genetic and epigenetic alterations. We seek to understand how these features inter-relate in the earliest phase of cancer development and through the course of disease progression. For this, we studied murine models of liver injury integrating the most commonly occurring gene mutations of CCA - including Kras, Tp53, Arid1a and Smad4 - as well as murine hepatobiliary cancer models and derived primary cell lines based on these mutations. Among commonly mutated genes in CCA, we found that Smad4 functions uniquely to restrict reactive cholangiocyte expansion to liver injury through restraint of the proliferative response. Inactivation of Smad4 accelerates carcinogenesis, provoking pre-neoplastic biliary lesions and CCA development in an injury setting. Expression analyses of Smad4-perturbed reactive cholangiocytes and CCA lines demonstrated shared enriched pathways, including cell-cycle regulation, MYC signaling and oxidative phosphorylation, suggesting that Smad4 may act via these mechanisms to regulate cholangiocyte proliferation and progression to CCA. Overall, we showed that TGFß/SMAD4 signaling serves as a critical barrier restraining cholangiocyte expansion and malignant transformation in states of biliary injury.
Subject(s)
Bile Duct Neoplasms , Proto-Oncogene Proteins c-myc , Animals , Mice , Signal Transduction , Carcinogenesis/genetics , Cell Proliferation , Bile Ducts, IntrahepaticABSTRACT
The cellular-level visualization of retinal microstructures such as blood vessel wall components, not available with other imaging modalities, is provided with unprecedented details by dark-field imaging configurations; however, the interpretation of such images alone is sometimes difficult since multiple structural disturbances may be present in the same time. Particularly in eyes with retinal pathology, microstructures may appear in high-resolution retinal images with a wide range of sizes, sharpnesses, and brightnesses. In this paper we show that motion contrast and phase gradient imaging modalities, as well as the simultaneous acquisition of depth-resolved optical coherence tomography (OCT) images, provide additional insight to help understand the retinal neural and vascular structures seen in dark-field images and may enable improved diagnostic and treatment plans.
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BACKGROUND: Metabolic and bariatric surgery (MBS) venous thromboembolism (VTE) prescribing practices vary widely. Our institutional VTE prophylaxis protocol has historically been unstandardized. OBJECTIVES: To create a standardized MBS VTE prophylaxis protocol, track protocol compliance, and identify barriers to protocol compliance and address them with Plan-Do-Study-Act (PDSA) cycles. SETTING: Single Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program-accredited academic hospital. METHODS: We conducted a retrospective study for all patients undergoing MBS (January 2019 to September 2022). A multidisciplinary group of bariatric clinicians reviewed literature and developed the following standardized VTE prophylaxis protocol: 5000 units preoperative subcutaneous (SC) heparin within 60 minutes of anesthesia induction and postoperative 40 mg SC low molecular weight heparin (LMWH) within 24 hours of surgery. This protocol was distributed to relevant clinical stakeholders. We assessed monthly compliance rates through chart review. Goal compliance was ≥90%. We identified sources of noncompliance and addressed them with PDSA methodology. RESULTS: A total of 796 patients were included. Preoperative heparin administration increased from a mean of 47% (107/228) preintervention to 96% (545/568) postintervention (P < .0001), and postoperative LMWH administration increased from 71% (47/66) to 96% (573/597, P = .0002). These compliance rates were sustained for 3 years. Barriers to protocol noncompliance included order set timing errors (n = 45), surgeon error (n = 44), surgeon discretion (n = 40), and nursing error (n = 20). No change in bleeding or VTE rates was observed. CONCLUSIONS: Developing a standardized VTE prophylaxis protocol, monitoring process measures, and engaging relevant stakeholders in PDSA cycles resulted in drastic and durable improvement in VTE prophylaxis compliance rates.
Subject(s)
Bariatric Surgery , Venous Thromboembolism , Humans , Venous Thromboembolism/etiology , Venous Thromboembolism/prevention & control , Heparin, Low-Molecular-Weight/therapeutic use , Retrospective Studies , Anticoagulants/therapeutic use , Heparin/therapeutic use , Academic Medical Centers , Postoperative Complications/prevention & control , Postoperative Complications/drug therapyABSTRACT
Since its discovery, surface-enhanced Raman spectroscopy (SERS) has shown outstanding promise of identifying trace amounts of unknown molecules in rapid, portable formats. However, the many different types of nanoparticles or nanostructured metallic SERS substrates created over the past few decades show substantial variability in the SERS spectra they provide. These inconsistencies have even raised speculation that substrate-specific SERS spectral libraries must be compiled for practical use of this type of spectroscopy. Here, we report a machine learning (ML) algorithm that can identify chemicals by matching their SERS spectra to those of a standard Raman spectral library. We use an approach analogous to facial recognition that utilizes feature extraction in the presence of multiple nuisance variables for spectral recognition. The key element is a metric we call "Characteristic Peak Similarity" (CaPSim) that focuses on the characteristic peaks in the SERS spectra. It has the flexibility to accommodate substrate-specific variability when quantifying the degree of similarity to a Raman spectrum. Analysis shows that CaPSim substantially outperforms existing spectral matching algorithms in terms of accuracy. This ML-based approach could greatly facilitate the spectroscopic identification of molecules in fieldable SERS applications.
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Diseases such as diabetes affect the retinal vasculature and the health of the neural retina, leading to vision problems. We describe here an imaging method and analysis procedure that enables characterization of the retinal vessel walls with cellular-level resolution, potentially providing markers for eye diseases. Adaptive optics scanning laser ophthalmoscopy is used with a modified detection scheme to include four simultaneous offset aperture channels. The magnitude of the phase gradient derived from these offset images is used to visualize the structural characteristics of the vessels. The average standard deviation image provides motion contrast and enables segmentation of the vessel lumen. Segmentation of blood vessel walls provides quantitative measures of geometrical characteristics of the vessel walls, including vessel and lumen diameters, wall thickness, and wall-to-lumen ratio. Retinal diseases may affect the structural integrity of the vessel walls, their elasticity, their permeability, and their geometrical characteristics. The ability to measure these changes is valuable for understanding the vascular effects of retinal diseases, monitoring disease progression, and drug testing. In addition, loss of structural integrity of the blood vessel wall may result in microaneurysms, a hallmark lesion of diabetic retinopathy, which may rupture or leak and further create vision impairment. Early identification of such structural abnormalities may open new treatment avenues for disease management and vision preservation. Functional testing of retinal circuitry through high-resolution measurement of vasodilation as a response to controlled light stimulation of the retina (neurovascular coupling) is another application of our method and can provide an unbiased evaluation of one's vision and enable early detection of retinal diseases and monitoring treatment results.
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INTRODUCTION: Surgery remains the cornerstone treatment for gastric cancer. Previous studies have reported better lymphadenectomy with minimally invasive approaches. There is a paucity of data comparing robotic and laparoscopic gastrectomy in the US. Herein, we examined whether oncological adequacy differs between laparoscopic and robotic approaches. METHODS: The National Cancer Database was utilized to identify patients who underwent gastrectomy for adenocarcinoma between 2010 and 2019. A propensity score-matching analysis between robotic gastrectomy (RG) versus laparoscopic gastrectomy (LG) was performed. The primary outcomes were lymphadenectomy ≥ 16 nodes and surgical margins. RESULTS: A total of 11,173 patients underwent minimally invasive surgery for gastric adenocarcinoma between 2010 and 2019. Of those 8320 underwent LG and 2853 RG. Comparing the unmatched cohorts, RG was associated with a higher rate of adequate lymphadenectomy (63.5% vs 57.1%, p < .0.0001), higher rate of negative margins (93.8% vs 91.9%, p < 0.001), lower rate of prolonged length of stay (26.0% vs 29.6%, p < .0.001), lower 90-day mortality (3.7% vs 5.0%, p < 0.0001), and a better 5-year overall survival (OS) (56% vs 54%, p = 0.03). A propensity score-matching cohort with a 1:1 ratio was created utilizing the variables associated with lymphadenectomy ≥ 16 nodes. The matched analysis revealed that the rate of adequate lymphadenectomy was significantly higher for RG compared to LG, 63.5% vs 60.4% (p = 0.01), respectively. There was no longer a significant difference between RG and LG regarding the rate of negative margins, prolonged length of stay, 90-day mortality, rate of receipt of postoperative chemotherapy, and OS. CONCLUSIONS: This propensity score-matching analysis with a large US cohort shows that RG was associated with a higher rate of adequate lymphadenectomy compared to LR. RG and LG had a similar rate of negative margins, prolonged length of stay, receipt of postoperative chemotherapy, 90-day mortality, and OS, suggesting that RG is a comparable surgical approach, if not superior to LG.
Subject(s)
Adenocarcinoma , Laparoscopy , Robotic Surgical Procedures , Stomach Neoplasms , Humans , Treatment Outcome , Propensity Score , Adenocarcinoma/surgery , Stomach Neoplasms/pathology , Gastrectomy , Retrospective Studies , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Postoperative Complications/surgeryABSTRACT
OBJECTIVE: African-Americans have the highest rate of colorectal cancer deaths. Adherence to colorectal cancer screening guidelines can improve outcomes. The objective of this study was to evaluate physician trust and barriers to screening utilizing a unique bi-directional learning focus group involving African-American adults and health care learners. METHODS: A focus group of African-American adults from a community church and university health care learners was conducted to identify colon cancer screening barriers. Health care learners were medical students, resident physicians and gastroenterology fellows. Pre-focus group surveys, including the Wake Forest Physician Trust Scale (WFPTS) and a colon cancer screening knowledge survey, were administered. Audio recording of the focus group was transcribed with subsequent thematic analysis. A post-focus group survey evaluated the colorectal cancer screening barriers identified during the focus group. Analysis of pre- and post- focus group surveys was performed using Fisher Exact test with significance set at p<0.05. RESULTS: The focus group consisted of 18 members (7 African-American community members, 11 non-African American health care learners). WFPTS revealed that 83% (86% community members, 82% health care learners; pâ¯=â¯1.0) strongly agree / agree that their physician would advocate for their health. 77% (86% community members, 73% health care learners; pâ¯=â¯1.0) strongly agree / agree that they trusted their physician. 100% recognized that colon cancer screening is recommended. The focus group identified lack of awareness (81%), colonoscopy preparation (81%), trust in physician (60%), lack of insurance coverage (56%), transportation (56%), colonoscopy wait time (50%), insufficient physician discussion (50%) and fear of procedure or cancer (35%) as screening barriers. Post-focus group surveys revealed that community members more frequently identified racial disparity in health care (pâ¯=â¯0.0474), physician respect toward patients (pâ¯=â¯0.0128) and insufficient physician discussion (pâ¯=â¯0.0006) as screening barriers. CONCLUSIONS: Focus group discussion identified multiple barriers for colorectal cancer screening. Notably, differences in the perceptions of African-American community members and non-African-American health care learners about racial disparity in health care, physician respect toward patients and insufficient physician discussion were revealed. The integration of bi-directional focus group learning can be considered as a potential strategy to assist in the development of focused screening interventions.