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1.
Pulm Circ ; 14(2): e12374, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38736894

RESUMO

Chronic thromboembolic pulmonary hypertension (CTEPH) is a sequela of a pulmonary embolus that occurs in approximately 1%-3% of patients. Pulmonary thromboendoarterectomy (PTE) can be a curative procedure, but balloon pulmonary angioplasty (BPA) has emerged as an option for poor surgical candidates. We used the National Inpatient Sample to query patients who underwent PTE or BPA between 2012 and 2019 with CTEPH. The primary outcome was a composite of in-hospital mortality, myocardial infarction, stroke, tracheostomy, and prolonged mechanical ventilation. Outcomes were compared between low- and high-volume centers, defined as 5 and 10 procedures per year for BPA and PTE, respectively. During our study period, 870 BPA and 2395 PTE were performed. There was a 328% relative increase in the number of PTE performed during the study period. Adverse events for BPA were rare. There was an increase in the primary composite outcome for low-volume centers compared to high-volume centers for PTE (24.4% vs. 12.1%, p = 0.003). Patients with hospitalizations for PTE in low-volume centers were more likely to have prolonged mechanical ventilation (20.0%% vs. 7.2%, p < 0.001) and tracheostomy (7.8% vs. 2.6%, p = 0.017). In summary, PTE rates have been rising over the past 10 years, while BPA rates have remained stable. While adverse outcomes are rare for BPA, patients with hospitalizations at low-volume centers for PTE were more likely to have adverse outcomes. For patients undergoing treatment of CTEPH with BPA or PTE, referral to high-volume centers with multidisciplinary teams should be encouraged for optimal outcomes.

2.
Med Biol Eng Comput ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38656734

RESUMO

This paper proposes a medical image fusion method in the non-subsampled shearlet transform (NSST) domain to combine a gray-scale image with the respective pseudo-color image obtained through different imaging modalities. The proposed method applies a novel improved dual-channel pulse-coupled neural network (IDPCNN) model to fuse the high-pass sub-images, whereas the Prewitt operator is combined with maximum regional energy (MRE) to construct the fused low-pass sub-image. First, the gray-scale image and luminance of the pseudo-color image are decomposed using NSST to find the respective sub-images. Second, the low-pass sub-images are fused by the Prewitt operator and MRE-based rule. Third, the proposed IDPCNN is utilized to get the fused high-pass sub-images from the respective high-pass sub-images. Fourth, the luminance of the fused image is obtained by applying inverse NSST on the fused sub-images, which is combined with the chrominance components of the pseudo-color image to construct the fused image. A total of 28 diverse medical image pairs, 11 existing methods, and nine objective metrics are used in the experiment. Qualitative and quantitative fusion results show that the proposed method is competitive with and even outpaces some of the existing medical fusion approaches. It is also shown that the proposed method efficiently combines two gray-scale images.

4.
Curr Cardiol Rep ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38466533

RESUMO

PURPOSE OF REVIEW: This review describes the presentation, diagnosis, and management of congenital coronary artery fistulas (CAFs) in adults. RECENT FINDINGS: CAFs are classified as coronary-cameral or coronary arteriovenous fistulas. Fistulous connections at the distal coronary bed are more likely to be aneurysmal with higher risk of thrombosis and myocardial infarction (MI). Medium-to-large or symptomatic CAFs can manifest as ischemia, heart failure, and arrhythmias. CAF closure is recommended when there are attributable symptoms or evidence of adverse coronary remodeling. Closure is usually achievable using transcatheter techniques, though large fistulas may require surgical ligation with bypass. Given their anatomic complexity, cardiac CT with multiplanar 3-D reconstruction can enhance procedural planning of CAF closure. Antiplatelet and anticoagulation are essential therapies in CAF management. CAFs are rare cardiac anomalies with variable presentations and complex anatomy. CAF management strategies include indefinite medical therapy, percutaneous or surgical CAF closure, and lifelong patient surveillance.

6.
Open Heart ; 11(1)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191233

RESUMO

BACKGROUND: A quarter of patients with severe aortic stenosis (AS) were asymptomatic, and only a third of them survived at the end of 4 years. Only a select subset of these patients was recommended for aortic valve replacement (AVR) by the current American College of Cardiology/American Heart Association guidelines. We intended to study the effect of early AVR (eAVR) in this subset of asymptomatic patients with preserved left ventricle function. METHODS AND RESULTS: We searched PubMed and Embase for randomised and observational studies comparing the effect of eAVR versus conservative therapy in patients with severe, asymptomatic AS and normal left ventricular function. The primary outcome was all-cause mortality. The secondary outcomes were composite major adverse cardiac events (MACE) (study defined), myocardial infarction (MI), stroke, cardiac death, sudden death, the development of symptoms, heart failure hospitalisations and major bleeding. We used GRADEPro to assess the certainty of the evidence. In the randomised controlled trial (RCT) only analysis, we found no significant difference in all-cause mortality between the early aortic intervention group versus the conservative arm (CA) (incidence rate ratio, IRR (CI): 0.5 (0.2 to 1.1), I2=31%, p=0.09). However, in the overall cohort, we found mortality benefit for eAVR over CA (IRR (CI): 0.4 (0.3 to 0.7), I2=84%, p<0.01). There were significantly lower MACE, cardiac death, sudden death, development of symptoms and heart failure hospitalisations in the eAVR group. We noticed no difference in MI, stroke and major bleeding. CONCLUSION: We conclude that there is no reduction in all-cause mortality in the eAVR arm in patients with asymptomatic AS with preserved ejection fraction. However, eAVR reduces heart failure related hospitalisations and death or heart failure hospitalisations. PROSPERO REGISTRATION NUMBER: CRD42022306132.


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Humanos , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/cirurgia , Tratamento Conservador/efeitos adversos , Morte Súbita Cardíaca/etiologia , Insuficiência Cardíaca/etiologia , Hemorragia/etiologia , Infarto do Miocárdio/etiologia , Acidente Vascular Cerebral/etiologia , Estados Unidos , Função Ventricular Esquerda , Implante de Prótese de Valva Cardíaca/efeitos adversos , Substituição da Valva Aórtica Transcateter/efeitos adversos
8.
Am J Cardiol ; 205: 406-412, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37659261

RESUMO

A subset of patients with myocarditis present with cardiogenic shock. There is a lack of contemporary data assessing the use of mechanical circulatory support (MCS) in these patients. Myocarditis hospitalizations were analyzed using the National Inpatient Sample between 2016 and 2019. Characteristics of patients with and without cardiogenic shock were assessed. Trends in mortality, MCS, right-sided cardiac catheterization (RHC) and endomyocardial biopsy were evaluated. The impact of RHC on consequent MCS and mortality was studied. A total of 38,300 hospitalizations for myocarditis were included in the study, of which 3,490 hospitalizations (9.1%) had cardiogenic shock. Patients with cardiogenic shock were older (p <0.001) and had more chronic kidney disease and atrial fibrillation. Between 2016 and 2019, there was an increase in myocarditis admissions but no difference in rates of cardiogenic shock and mortality and the use of extracorporeal membrane oxygenation, percutaneous ventricular assist devices, intra-aortic balloon pumps, left ventricular assist devices, and cardiac transplant. The most common form of MCS used in myocarditis was extracorporeal membrane oxygenation. The rates of RHC (p = 0.02) and endomyocardial biopsy (p = 0.03) increased over time. Patients who underwent RHC were more likely to receive mechanical support, and in patients with shock, RHC was associated with lower mortality (adjusted odds ratio 0.34, p <0.01). Myocarditis admissions increased over time but with no increase in the rates of cardiogenic shock and MCS. In patients with cardiogenic shock, RHC resulted in lower mortality.


Assuntos
Fibrilação Atrial , Miocardite , Humanos , Pacientes Internados , Choque Cardiogênico/epidemiologia , Choque Cardiogênico/terapia , Miocardite/epidemiologia , Miocardite/terapia , Incidência
9.
Eur Heart J Case Rep ; 7(6): ytad260, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37501915

RESUMO

Background: Cardiac angiosarcoma is an exceptionally rare primary malignant tumour with an aggressive course and typically poor prognosis. Diagnosis is difficult, and patients often present with metastatic disease. We report the rare case of a patient with cardiac angiosarcoma who presents with constrictive physiology due to tumour encasement. Case summary: A 65-year-old female with a past medical history of Hodgkin's lymphoma and limited scleroderma presented with progressive dyspnoea on exertion. Multimodality imaging and haemodynamics with echocardiography, cardiac magnetic resonance imaging (MRI), and cardiac catheterization showed findings of constrictive physiology. Cardiac MRI showed areas of pericardial enhancement, so she was initially started on colchicine, prednisone, and mycophenolate mofetil to treat pericardial inflammation. However, her symptoms progressed, and she underwent pericardiectomy with cardiac surgery. Pericardium was noted to be thickened and a mass-like substance was densely adherent and potentially invading the heart itself and could not be dissected free. Surgical pathology showed features consistent with epithelioid angiosarcoma. Patient had rapid progression of her disease and was started on chemotherapy. Her course, however, was complicated by acute gastrointestinal bleeding, atrial fibrillation with rapid rates, and persistent volume overload. She elected for comfort measures and passed away shortly after her diagnosis. Discussion: Our case shows an extremely rare diagnosis, cardiac angiosarcoma, presenting with typical findings of constrictive physiology. The case shows the typical features of constrictive physiology using multimodality imaging and haemodynamics and emphasizes the need to always think broadly in creating a differential diagnosis for constriction to ensure that rare diseases are considered.

10.
Clin Med Insights Case Rep ; 16: 11795476231174196, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37325178

RESUMO

Background: Juvenile dermatomyositis (JDM) is an autoimmune connective tissue disorder characterized by an inflammation of proximal muscles of both upper and lower limbs in children below the age of 18 years. The condition mainly involves the proximal muscles and skin but extra-muscular involvement such as the gastrointestinal tract, lungs, and heart are also common. Case presentation: We present a case of a 12-year-old south Asian male who developed weakness and muscular pain in all 4 extremities at 3 years of age. The condition gradually worsened recently, and the patient developed tender ulcerated skin nodules. Power in all 4 limbs was decreased and the patient was not able to perform his routine work such as combing of hair, closing a shirt button, and walking. Laboratory investigations revealed raised total leukocyte count (TLC) and erythrocyte sedimentation rate (ESR) and biopsy of the proximal muscles and skin lesions showed focal mild necrotic infiltrate involving nonnecrotic muscle fibers and calcinosis cutis respectively. A diagnosis of JDM was made and the patient was started on immunosuppressive therapy (steroids) and diltiazem. Conclusion: JDM shares clinical features with other autoimmune, genetic, and inflammatory conditions. Proper history, thorough clinical examination, and laboratory workup is needed to rule out other masquerading conditions. This case report also highlighted the importance of diltiazem in the treatment of calcinosis cutis which is more commonly seen in patients with dermatomyositis.

11.
Cardiovasc Revasc Med ; 54: 25-30, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36842933

RESUMO

BACKGROUND: Patients with symptomatic calcified coronary lesions have poor outcomes. Such lesions require additional atherectomy devices for bed preparation. AIM: To assess the safety and efficacy of OPN balloon in patients with calcified coronary lesions. METHODS: This is an investigator-initiated, prospective, observational study. The primary outcome of the study was a procedural success. RESULTS: We studied 71 patients (133 lesions). Maximum lesions were located in LAD [46.6 %]. The OPN balloon was used for pre-dilatation alone in 28.6 % (Pre-stent OPN group), post-dilatation alone in 63.2 % of lesions (Post-stent OPN group), and in both situations in 8.3 % of lesions with procedural success in 98.5 % of patients. Further dilatation with different NC balloons was required in both groups (30 %). The median (IQR) OPN balloon diameter in the pre- and post-stent OPN group were 2.5 (2.5, 3.0) and 3.0 (3.0,3.0) mm (p = 0.001), respectively. The difference between the diameter of the stent and OPN balloon used in pre-stent OPN group was 0.5 (0.2, 0.5) mm while it was 0.0 (0.0,0.2) mm in the post-stent OPN group (p < 0.001). Eight complications and two deaths occured. Distal shaft rupture was also noticed. CONCLUSION: OPN balloon is safe, and effective in treating calcified coronary lesions. We propose to undersize the balloon by 0.5 mm for pre-dilatation followed by 0.25 mm larger NC balloon if needed. In the post-dilatation group, use a 1:1 size balloon in a non-tortuous straight segment. Use imaging especially when (1) the pressure taken more than the rated burst pressure, (2) an OPN balloon size is ≥3 mm (3) using 1:1 size OPN balloon in a tortuous segment.


Assuntos
Angioplastia Coronária com Balão , Aterectomia Coronária , Doença da Artéria Coronariana , Calcificação Vascular , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/terapia , Estudos Prospectivos , Aterectomia Coronária/métodos , Angiografia Coronária , Resultado do Tratamento , Stents , Calcificação Vascular/diagnóstico por imagem , Calcificação Vascular/terapia
12.
Eur Heart J Case Rep ; 7(1): ytad011, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36694871

RESUMO

Background: Coronary artery fistulae are abnormal communications of coronary arteries with systemic vasculature, pulmonary vasculature, or cardiac chambers. Use of multimodality imaging can be paramount to understanding anatomical and functional features of these complex vascular lesions, therefore optimizing success of potential curative interventions. Case summary: We present two patients with incidentally discovered giant aneurysmal coronary arteries with distal fistulous connections to the coronary sinus, which were successfully closed percutaneously with Amplatzer Septal Occluders using the assistance of three-dimensional (3D) printed heart models. Conclusion: Computed tomography-guided reconstruction with 3D multiplanar, multicolour printed models can help augment visuospatial understanding of the size, origin, course, and drainage of giant aneurysmal coronary artery-to-coronary sinus fistulae, and with manual bench testing can assist with choosing accurately sized and shaped devices for closure.

13.
AIDS ; 37(3): 401-411, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36384811

RESUMO

OBJECTIVE: Liver disease is accelerated in people with HIV (PWH) with hepatitis B virus (HBV) coinfection. We hypothesized that liver fibrosis in HIV-HBV is triggered by increased hepatocyte apoptosis, microbial translocation and/or HIV/HBV viral products. DESIGN: Sera from PWH with HBV coinfection versus from those with HBV only or putative mediators were used to examine the pathogenesis of liver disease in HIV-HBV. METHODS: We applied sera from PWH and HBV coinfection versus HBV alone, or putative mediators (including HMGB1), to primary human hepatic stellate cells (hHSC) and examined pro-fibrogenic changes at the single cell level using flow cytometry. High mobility group box 1 (HMGB1) levels in the applied sera were assessed according to donor fibrosis stage. RESULTS: Quantitative flow cytometric assessment of pro-fibrogenic and inflammatory changes at the single cell level revealed an enhanced capacity for sera from PWH with HBV coinfection to activate hHSC. This effect was recapitulated by lipopolysaccharide, HIV-gp120, hepatocyte conditioned-media and the alarmin HMGB1. Induction of hepatocyte cell death increased their pro-fibrogenic potential, an effect blocked by HMGB1 antagonist glycyrrhizic acid. Consistent with a role for this alarmin, HMGB1 levels were elevated in sera from PWH and hepatitis B coinfection compared to HBV alone and higher in those with HIV-HBV with liver fibrosis compared to those without. CONCLUSIONS: Sera from PWH and HBV coinfection have an enhanced capacity to activate primary hHSC. We identified an increase in circulating HMGB1 which, in addition to HIV-gp120 and translocated microbial products, drove pro-fibrogenic changes in hHSC, as mechanisms contributing to accelerated liver disease in HIV-HBV.


Assuntos
Coinfecção , Infecções por HIV , Proteína HMGB1 , Hepatite B , Humanos , Vírus da Hepatite B , Alarminas , Hepatite B/complicações , Cirrose Hepática/patologia
15.
BJR Case Rep ; 8(3): 20210072, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36101735

RESUMO

Osteofibrous dysplasia is a rare non-malignant fibro-osseous bone tumour, first described and characterised under this name by Campanacci in 1976. It is most commonly encountered in the tibia of children and young adults, but less frequently seen in the neonate with only few prior reports in the literature. We report a case of neonatal congenital osteofibrous dysplasia, presenting with unilateral limb deformity at birth. Radiographs demonstrated well-defined mixed lytic-sclerotic lesions, in a previously unreported distribution in this age-group, confined to the distal metadiaphysis of the affected tibia and fibula. Open surgery was performed for deformity correction, with tissue biopsy confirming the radiographically-suspected diagnosis. We present the up-to-date clinical, radiological and pathological findings in this case of a rare pathology with some novel features, within this age group, in disease distribution and consequent radiographic appearances. OFD should be considered in the differential of similar congenital deforming bone lesions of the lower limb. We also review the small number of previously published cases of congenital OFD in the neonate, noting in particular that the frequency of ipsilateral fibular involvement appears to be higher than that observed in older patients.

16.
Diabetes Care ; 45(11): 2636-2643, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36126177

RESUMO

OBJECTIVE: To document glycemic and user-initiated bolus changes following transition from predictive low glucose suspend (PLGS) system to automated insulin delivery (AID) system during real-life use. RESEARCH DESIGN AND METHODS: We conducted analysis of 2,329,166 days (6,381 patient-years) of continuous glucose monitoring (CGM) and insulin therapy data for 19,354 individuals with type 1 Diabetes, during 1-month PLGS use (Basal-IQ technology) followed by 3-month AID use (Control-IQ technology). Baseline characteristics are as follows: 55.4% female, age (median/quartiles/range) 39/19-58/1-92 years, mean ± SD glucose management indicator (GMI) 7.5 ± 0.8. Primary outcome was time in target range (TIR) (70-180 mg/dL). Secondary outcomes included CGM-based glycemic control metrics and frequency of user-initiated boluses. RESULTS: Compared with PLGS, AID increased TIR on average from 58.4 to 70.5%. GMI and percent time above and below target range improved as well: from 7.5 to 7.1, 39.9 to 28.1%, and 1.66 to 1.46%, respectively; all P values <0.0001. Stratification of outcomes by age and baseline GMI revealed clinically significant differences. Glycemic improvements were most pronounced in those <18 years old (TIR improvement 14.0 percentage points) and those with baseline GMI >8.0 (TIR improvement 13.2 percentage points). User-initiated correction boluses decreased from 2.7 to 1.8 per day, while user-initiated meal boluses remained stable at 3.6 to 3.8 per day. CONCLUSIONS: Observed in real life of >19,000 individuals with type 1 diabetes, transitions from PLGS to AID resulted in improvement of all glycemic parameters, equivalent to improvements observed in randomized clinical trials, and reduced user-initiated boluses. However, glycemic and behavioral changes with AID use may differ greatly across different demographic and clinical groups.


Assuntos
Diabetes Mellitus Tipo 1 , Insulina , Feminino , Humanos , Adolescente , Masculino , Automonitorização da Glicemia/métodos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Glicemia , Hipoglicemiantes/uso terapêutico , Insulina Regular Humana/uso terapêutico
17.
JTCVS Open ; 11: 351-362, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36172453

RESUMO

Objectives: Tricuspid valve (TV) surgery remains understudied and little data exist describing the surgical indications, outcomes, and prognostic factors for pediatric patients with non-Ebstein 2-ventricle congenital TV lesions. This study aims to describe early and late outcomes of pediatric patients with non-Ebstein congenital TV lesions undergoing isolated TV procedures at a single institution. Methods: All patients who underwent TV surgery for non-Ebstein congenital TV disease between 2006 and 2018 were included. Patients who had missing preoperative data, patients with single-ventricle physiology, congenitally corrected transposition of the great arteries, and patients undergoing TV intervention as part of repair of an atrioventricular canal defect were excluded. The primary end point was the occurrence of TV reintervention or TV regurgitation (TR) ≥ moderate. Results: A total of 85 patients were included. The tricuspid lesion was isolated TR in 80 (94.1%), isolated tricuspid stenosis in 3 (3.5%) and mixed disease in 2 (2.4%) patients. Median age at surgery was 33 years (interquartile range, 12-53 years). TV repair and TV replacement were performed in 66 (77.6%) and 19 (22.4%) patients, respectively. One (1.2%) patient underwent TV reoperation during the same admission. There was no in-hospital mortality. Median follow-up was 3.3 years (interquartile range, 0.1-4.7 years). The overall cumulative incidence of TV reintervention or TR deemed moderate or greater at 1, 3, and 5 years was 3% ± 2%, 11% ± 4%, and 20% ± 8%. In multivariable analysis, age younger than 12 years (P = .04) and mitral valve regurgitation deemed moderate or greater (P = .01) were independent risk factors for TV reintervention or recurrent TR deemed to be moderate or greater at last follow-up. Conclusions: TV surgery in patients with non-Ebstein congenital TV disease can be performed with good outcomes. TV reintervention or TR deemed moderate or greater occurred in 20% of patients on midterm follow-up. Patients younger than age 12 years are at higher risk for recurrent TR or TV reintervention, whereas preoperative MR deemed moderate or greater increases this risk, especially in patients older than age 12 years. There was no difference in outcomes between TV replacement and repair.

18.
Pediatr Radiol ; 52(13): 2538-2548, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35666285

RESUMO

BACKGROUND: More than half of paediatric radiology research presented at annual conference meetings between 2010-2012 remains unpublished. It is unclear if there are any improvements in this statistic despite some initiatives to improve awareness of the importance of evidence-based medicine. OBJECTIVES: To determine the abstract to publication rates (APRs) originating from recent paediatric radiology meetings, trends in research topics and factors associated with publication success. MATERIALS AND METHODS: All PubMed cited articles originating from oral presentations at European Society of Paediatric Radiology, Society for Paediatric Radiology or International Paediatric Radiology conferences between 2013-2016 were evaluated, and compared to those from previously published data from the same conferences dated 2010-2012. Publication rates, study design and topic as well as characteristics of the research group (e.g., author affiliations and number) were evaluated and compared between published and unpublished groups. RESULTS: The APR increased to 433/937 (46%) for abstracts presented between 2013-2016, compared to 300/715 (42%) in 2010-2012 (P=0.094). The largest proportion of publications comes from academic and tertiary centres (324/433 [75%]). International collaboration increased to 49/433 (11%) from 18/300 (6%) in 2010-2012 (P=0.018). A greater proportion of work was published within 12 months of conference: 41% in 2013-2016, compared to 29% in 2010-2012 (P=0.02). Paediatric Radiology remained the most popular destination journal, publishing 167/433 (39%) articles. CONCLUSION: There was a slight increase over time in the proportion of abstracts that resulted in publication, yet more than half of abstracts still do not reach publication status. Further work should identify how radiologists (particularly those outside tertiary and academic centres) can be supported to share their research.


Assuntos
Indexação e Redação de Resumos , Radiologia , Criança , Humanos , Sociedades Médicas , Radiografia , Projetos de Pesquisa
19.
Front Neurosci ; 16: 869671, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35527822

RESUMO

Early-life seizures (ELS) are often associated with the development of cognitive deficits. However, methods to predict and prevent these deficits are lacking. To increase the range of research models available to study cognitive consequences of ELS, we investigated whether seizures in larval zebrafish (Danio rerio) lead to behavioral deficits later in life. We thus modified the existing pentylenetetrazole (PTZ)-induced seizure model in larval zebrafish, exposing zebrafish to PTZ daily from 5 to 7 days post-fertilization (dpf). We then compared later-life learning, social behavior (shoaling), and behavioral and chemical measures of anxiety in the PTZ-exposed zebrafish (PTZ group) to that of naïve clutchmates (untouched controls, UC) and to a second control group (handling control, HC) that experienced the same handling as the PTZ group, but without PTZ exposure. We observed that only the PTZ group displayed a significant deficit in a y-maze learning task, while only the HC group displayed a social deficit of decreased shoaling. HC fish also showed an increased frequency of behavioral freezing and elevated cortisol responses to netting, heightened stress responses not seen in the PTZ fish. Since mild stressors, such as the handling the HC fish experienced, can lead to learned, advantageous responses to stress later in life, we tested escape response in the HC fish using an acoustic startle stimulus. The HC group showed an enhanced startle response, swimming significantly farther than either the PTZ or UC group immediately after being startled. Taken together, these results indicate that seizures in larval zebrafish impair learning and the development of an adaptive, heightened stress response after early-life stress. These findings expand the behavioral characterization of the larval zebrafish seizure model, strengthening the power of this model for ELS research.

20.
Sci Robot ; 7(65): eabl6307, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35442701

RESUMO

Current space exploration roadmaps envision exploring the surface geology of celestial bodies with robots for both scientific research and in situ resource utilization. In such unstructured, poorly lit, complex, and remote environments, automation is not always possible, and some tasks, such as geological sampling, require direct teleoperation aided by force-feedback (FF). The operator would be on an orbiting spacecraft, and poor bandwidth, high latency, and packet loss from orbit to ground mean that safe, stable, and transparent interaction is a substantial technical challenge. For this scenario, a control method was developed that ensures stability at high delay without reduction in speed or loss of positioning accuracy. At the same time, a new level of safety is achieved not only through FF itself but also through an intrinsic property of the approach preventing hard impacts. On the basis of this method, a tele-exploration scenario was simulated in the Analog-1 experiment with an astronaut on the International Space Station (ISS) using a 6-degree-of-freedom (DoF) FF capable haptic input device to control a mobile robot with manipulator on Earth to collect rock samples. The 6-DoF FF telemanipulation from space was performed at a round-trip communication delay constantly between 770 and 850 milliseconds and an average packet loss of 1.27%. This experiment showcases the feasibility of a complete space exploration scenario via haptic telemanipulation under spaceflight conditions. The results underline the benefits of this control method for safe and accurate interactions and of haptic feedback in general.


Assuntos
Robótica , Retroalimentação , Geologia , Órbita , Planetas
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