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1.
Mamm Biol ; 102(3): 921-933, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36164481

RESUMEN

To address biodiversity decline in the era of big data, replicable methods of data processing are needed. Automated methods of individual identification (ID) via computer vision are valuable in conservation research and wildlife management. Rapid and systematic methods of image processing and analysis are fundamental to an ever-growing need for effective conservation research and practice. Bears (ursids) are an interesting test system for examining computer vision techniques for wildlife, as they have variable facial morphology, variable presence of individual markings, and are challenging to research and monitor. We leveraged existing imagery of bears living under human care to develop a multispecies bear face detector, a critical part of individual ID pipelines. We compared its performance across species and on a pre-existing wild brown bear Ursus arctos dataset (BearID), to examine the robustness of convolutional neural networks trained on animals under human care. Using the multispecies bear face detector and retrained sub-applications of BearID, we prototyped an end-to-end individual ID pipeline for the declining Andean bear Tremarctos ornatus. Our multispecies face detector had an average precision of 0.91-1.00 across all eight bear species, was transferable to images of wild brown bears (AP = 0.93), and correctly identified individual Andean bears in 86% of test images. These preliminary results indicate that a multispecies-trained network can detect faces of a single species sufficiently to achieve high-performance individual classification, which could speed-up the transferability and application of automated individual ID to a wider range of taxa. Supplementary Information: The online version contains supplementary material available at 10.1007/s42991-021-00168-5.

2.
Dig Dis Sci ; 66(4): 1127-1141, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32328893

RESUMEN

BACKGROUND: Factors underlying gastroparesis are not well defined. AIMS: We hypothesized that multiple systems may be involved in patients with gastroparesis symptoms and performed a comparative physiologic study. METHODS: We studied 43 consecutive eligible patients with gastroparetic symptoms categorized by GI symptoms, metabolic status, illness quantification, and gastric physiology. Patients were evaluated by two methods in each of five core areas: inflammatory, autonomic, enteric, electrophysiologic, and hormonal with abnormalities examined by correlations. RESULTS: Patients had similar GI symptoms regardless of baseline gastric emptying or diabetic/idiopathic status, and all patients demonstrated abnormalities in each of the 5 areas studied. Nearly all patients presented with elevated markers of serum TNFα (88%) and serum IL-6 (91%); elevated cutaneous electrogastrogram frequency (95%); and interstitial cells of Cajal count abnormalities (inner: 97%, outer: 100%). Measures of inflammation correlated with a number of autonomic, enteric anatomy, electrophysiologic and hormonal abnormalities. CONCLUSIONS: We conclude that patients with the symptoms of gastroparesis have multiple abnormalities, when studied by traditional, as well as newer, diagnostic assessments. Inflammation appears to be a fundamental abnormality that affects other organ systems in symptomatic patients. Future work on gastroparetic syndromes and their treatment may benefit from a focus on the diffuse nature of their illness, diverse pathophysiologic mechanisms involved, especially the possible causes of underlying inflammation and disordered hormonal status. TRAIL REGISTRY: This study is registered with Clinicaltrials.gov under study # NCT03178370 https://clinicaltrials.gov/ct2/show/NCT03178370 .


Asunto(s)
Vaciamiento Gástrico/fisiología , Mucosa Gástrica/fisiopatología , Gastroparesia/sangre , Gastroparesia/fisiopatología , Mediadores de Inflamación/sangre , Adulto , Femenino , Mucosa Gástrica/patología , Gastroparesia/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Síndrome
4.
Support Care Cancer ; 25(1): 27-31, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27534962

RESUMEN

PURPOSE: Malignancy-associated gastroparesis (MAG) is a cause of morbidity in cancer patients but therapies are lacking. Gastric electrical stimulation (GES) is a novel treatment for MAG. Here, we describe 19 patients with MAG who underwent temporary GES placement. PATIENTS AND METHODS: Nineteen patients (6 males, 13 females) with various malignancies were reviewed for symptom scores and physiologic measures at baseline and after temporary GES placement. Symptoms were scored by three variables: nausea (N), vomiting (V), and GI total symptom score (TSS). Physiologic profiles were measured by solid and liquid phase gastric emptying scans (GET) at 1, 2, and 4 h and cutaneous electrogastrogram (EGG) and mucosal electrogram (EG) frequencies. Symptoms were measured for 5 days after temporary endoscopic GES placement, and measures were repeated post GES placement. RESULTS: Baseline GET results displayed delayed gastric emptying in 16 of 19 patients (mean solid retention 21.7 % at 4 h, normal <10 %; mean liquid retention 10.4 % at 4 h, normal <5 %). Cutaneous EGG (mean frequency 5.5 cpm) and EG (mean proximal frequency 5.1 cpm; mean distal frequency 5.1 cpm) showed evidence of neuromuscular dysfunction (normal 2.5-3.3 cpm). Symptom scores in N, V, and TSS showed statistically significant reduction after GES placement. CONCLUSION: A small sample of patients with MAG and receiving temporary GES experienced symptom improvement, with less change on gastric emptying time or gastric electrical amplitude or frequency. GES may provide a potential therapeutic option for symptomatic management of MAG and evaluation of these MAG patients after permanent GES placement is ongoing. Prospective studies of MAG using temporary and permanent GES may be warranted.


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Gastroparesia/terapia , Prótesis e Implantes/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
6.
ASAIO J ; 69(6): 588-594, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36804288

RESUMEN

Assessment of frailty is key for evaluation for advanced therapies (ATs). Most programs use a subjective provider assessment (SPA) or "eye-ball" test; however, objective measures exist. The modified five-item Fried Frailty Index (mFFI) is a validated tool to assess frailty. We compared SPA to mFFI testing in patients referred for AT. We also compared levels of macrophage migration inhibitory factor (MIF), an inflammatory biomarker associated with worse outcomes in heart failure, between frail and not frail subjects. Seventy-eight patients referred for evaluation for AT underwent both SPA and mFFI testing. Three cardiac surgeons independently assessed patients for frailty (SPA). SPA significantly underestimated frailty compared with mFFI testing and correlation between SPA and mFFI was not strong (κ = 0.02-0.14). Providers were correct 84% of the time designating a subject as frail, but only 40% of the time designating as not frail. Agreement between all three providers was robust (76%), which was primarily driven by designation as not frail. There was no significant difference in plasma MIF levels between frail and not frail subjects (47.6 ± 25.2 vs . 45.2 ± 18.9 ng/ml; p = 0.6). Clinicians significantly underestimate frailty but are usually correct when designating a patient as frail.


Asunto(s)
Fragilidad , Insuficiencia Cardíaca , Humanos , Biomarcadores , Fragilidad/diagnóstico , Insuficiencia Cardíaca/terapia , Insuficiencia Cardíaca/complicaciones
7.
J Exp Med ; 203(7): 1637-42, 2006 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-16818669

RESUMEN

Severe sepsis, a lethal syndrome after infection or injury, is the third leading cause of mortality in the United States. The pathogenesis of severe sepsis is characterized by organ damage and accumulation of apoptotic lymphocytes in the spleen, thymus, and other organs. To examine the potential causal relationships of apoptosis to organ damage, we administered Z-VAD-FMK, a broad-spectrum caspase inhibitor, to mice with sepsis. We found that Z-VAD-FMK-treated septic mice had decreased levels of high mobility group box 1 (HMGB1), a critical cytokine mediator of organ damage in severe sepsis, and suppressed apoptosis in the spleen and thymus. In vitro, apoptotic cells activate macrophages to release HMGB1. Monoclonal antibodies against HMGB1 conferred protection against organ damage but did not prevent the accumulation of apoptotic cells in the spleen. Thus, our data indicate that HMGB1 production is downstream of apoptosis on the final common pathway to organ damage in severe sepsis.


Asunto(s)
Apoptosis/inmunología , Proteína HMGB1/fisiología , Sepsis/mortalidad , Sepsis/patología , Clorometilcetonas de Aminoácidos/farmacología , Animales , Anticuerpos Monoclonales/uso terapéutico , Apoptosis/efectos de los fármacos , Inhibidores de Caspasas , Femenino , Proteína HMGB1/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Sepsis/inmunología , Sepsis/terapia
8.
ESC Heart Fail ; 9(4): 2272-2278, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35451212

RESUMEN

AIMS: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly being used to support patients in cardiogenic shock (CS). Early determination of disposition is paramount, as longer durations of support have been associated with worse outcomes. We describe a stepwise, bedside weaning protocol to assess cardiopulmonary recovery during VA-ECMO. METHODS AND RESULTS: Over 1 year, we considered all patients on VA-ECMO for CS for the Weaning Protocol (WP) at our centre. During the WP, patients had invasive haemodynamic monitoring, echocardiography, and blood gas analysis while flow was reduced in 1 LPM decrements. Ultimately, the circuit was clamped for 30 min, and final measures were taken. Patients were described as having durable recovery (DR) if they were free of pharmacological and mechanical support at 30 days post-decannulation. Over 12 months, 34 patients had VA-ECMO for CS. Fourteen patients were eligible for the WP at 4-12 days. Ten patients tolerated full flow reduction and were successfully decannulated. Twenty-four per cent of the entire cohort demonstrated DR with no adverse events during the WP. Patients with DR had significantly higher ejection fraction, cardiac index, and smaller left ventricular size at lowest flow during the WP. CONCLUSIONS: We describe a safe, stepwise, bedside weaning protocol to assess cardiac recovery during VA-ECMO. Early identification of patients more likely to recover may improve outcomes during ECMO support.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Oxigenación por Membrana Extracorpórea/métodos , Corazón , Humanos , Choque Cardiogénico/etiología , Volumen Sistólico , Función Ventricular Izquierda
9.
Ecol Evol ; 10(23): 12883-12892, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33304501

RESUMEN

Emerging technologies support a new era of applied wildlife research, generating data on scales from individuals to populations. Computer vision methods can process large datasets generated through image-based techniques by automating the detection and identification of species and individuals. With the exception of primates, however, there are no objective visual methods of individual identification for species that lack unique and consistent body markings. We apply deep learning approaches of facial recognition using object detection, landmark detection, a similarity comparison network, and an support vector machine-based classifier to identify individuals in a representative species, the brown bear Ursus arctos. Our open-source application, BearID, detects a bear's face in an image, rotates and extracts the face, creates an "embedding" for the face, and uses the embedding to classify the individual. We trained and tested the application using labeled images of 132 known individuals collected from British Columbia, Canada, and Alaska, USA. Based on 4,674 images, with an 80/20% split for training and testing, respectively, we achieved a facial detection (ability to find a face) average precision of 0.98 and an individual classification (ability to identify the individual) accuracy of 83.9%. BearID and its annotated source code provide a replicable methodology for applying deep learning methods of facial recognition applicable to many other species that lack distinguishing markings. Further analyses of performance should focus on the influence of certain parameters on recognition accuracy, such as age and body size. Combining BearID with camera trapping could facilitate fine-scale behavioral research such as individual spatiotemporal activity patterns, and a cost-effective method of population monitoring through mark-recapture studies, with implications for species and landscape conservation and management. Applications to practical conservation include identifying problem individuals in human-wildlife conflicts, and evaluating the intrapopulation variation in efficacy of conservation strategies, such as wildlife crossings.

10.
Neurogastroenterol Motil ; 31(3): e13534, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30706646

RESUMEN

BACKGROUND AND AIMS: Factors underlying gastroparesis are not well defined, nor is the mechanism of action of gastric electrical stimulation (GES). We hypothesized that GES acts via several mechanisms related to underlying disordered pathophysiology. METHODS: We studied 43 consecutive eligible patients with gastroparetic symptoms, previously evaluated by two methods in each of five core areas: inflammatory, autonomic, enteric, electrophysiologic, and hormonal; and also categorized by GI symptoms, metabolic status, illness quantification, and gastric physiology. We then studied 41 patients who underwent temporary GES for 5-7 days. Thirty-six of those patients were implanted and 30 were followed up at 6 months after permanent GES. RESULTS: In previous but separately reported work, patients had similar GI symptoms regardless of baseline gastric emptying or diabetic/idiopathic status and all patients demonstrated abnormalities in each of the five areas studied. After GES, patients showed early and late effects of electrical stimulation with changes noted in multiple areas, categorized by improvement status. CONCLUSION: Patients with symptoms of gastroparesis have multiple abnormalities, including systemic inflammation and disordered hormonal status. GES affects many of these abnormalities. We conclude electrical stimulation improves symptoms and physiology with (a) an early and sustained anti-emetic effect; (b) an early and durable gastric prokinetic effect in delayed emptying patients; (c) an early anti-arrhythmic effect that continues over time; (d) a late autonomic effect; (e) a late hormonal effect; (f) an early anti-inflammatory effect that persists; and (g) an early and sustained improvement in health-related quality of life. This study is registered with Clinicaltrials.gov under study # NCT03178370 (https://clinicaltrials.gov/ct2/show/NCT03178370).


Asunto(s)
Terapia por Estimulación Eléctrica/métodos , Gastroparesia/terapia , Dolor Abdominal/etiología , Adulto , Anciano , Arritmias Cardíacas/etiología , Arritmias Cardíacas/terapia , Sistema Nervioso Autónomo/fisiopatología , Citocinas/análisis , Citocinas/metabolismo , Diabetes Mellitus/epidemiología , Femenino , Vaciamiento Gástrico , Gastroparesia/fisiopatología , Gastroparesia/psicología , Frecuencia Cardíaca , Hormonas/sangre , Humanos , Inflamación/patología , Masculino , Persona de Mediana Edad , Calidad de Vida , Resultado del Tratamiento , Vómitos/etiología , Vómitos/prevención & control , Vómitos/terapia
11.
Am Surg ; 82(4): 337-42, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27097627

RESUMEN

We compared outcomes for two gastric electrical stimulation placement strategies, minilaparotomy with adjunctive care (MLAC) versus laparoscopy without adjunctive care (LAPA). For electrode placement, the peritoneal cavity was accessed with either a single 2.5 to 3.0 cm midline incision (MLAC) or three trocar incisions (LAPA). For both groups, generator was placed subcutaneously over the anterior rectus sheath. For MLAC, adjunctive pain control measures were used for placement of both electrode and generator (transversus abdominus plane block). For LAPA, those that could not be completed by laparoscopy were converted to traditional open approach and kept in the analysis. MLAC (n = 128) resulted in shorter operative times than LAPA (n = 37) (median operative time: 87.5 vs 137.0 minutes, P ≤ 0.01). Hospital length of stay was also shorter for MLAC than for LAPA (median: 2.0 vs 3.0 days, P ≤ 0.01) without any increase in readmission rates to the hospital within 30 days of discharge (11.0 vs 16.2%, P = 0.39). After equalizing learning curves, these differences were even greater (median operative time: 84.5 vs 137.0 minutes, P < 0.01; median length of stay: 1.0 vs 3.0 days; P < 0.01) without increasing 30-day readmission rates (9.1 vs 16.2%, P = 0.25). For implantation of gastric electrical stimulators, minilaparotomy can result in improved outcomes when coupled with adjunctive pain control measures.


Asunto(s)
Terapia por Estimulación Eléctrica/instrumentación , Electrodos Implantados , Gastroparesia/cirugía , Laparoscopía/métodos , Laparotomía/métodos , Dolor Postoperatorio/prevención & control , Cuidados Posoperatorios/métodos , Adulto , Anciano , Amidas/uso terapéutico , Anestésicos Locales/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Tempo Operativo , Readmisión del Paciente/estadística & datos numéricos , Ropivacaína
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