Embedded Computational Heart Model for External Ventricular Assist Device Investigations

xlomafota.13 shared this article with you from Inoreader Embedded Computational Heart Model for External Ventricular Assist Device Investigations Via Latest Results for Cardiovascular Engineering and Technology Abstract Purpose External cardiac assist devices are based on a promising and simple concept for treating heart failure, but they are surprisingly difficult to design. Thus, a structured approach combining experiments with computer-based optimization is essential. The latter provides the motivation for the work presented in this paper. Methods We present a computational modeling framework for realistic representation of the heart's tissue structure, electrophysiology and actuation. The passive heart tissue is described by a nonlinear anisotropic material law, considering fiber and sheetlet directions. For muscle contraction, an orthotropic active-strain model is employed, initiated by a periodically propagating electrical potential. The model allows for boundary conditions at the epicardium accounting for external assist devices, and it is coupled to a circulation network providing appropriate pressure boundary conditions inside the ventricles. Results Simulated results from an unsupported healthy and a pathological heart model are presented and reproduce accurate deformations compared to phenomenological measurements. Moreover, cardiac output and ventricular pressure signals are in good agreement too. By investigating the impact of applying an exemplary external actuation to the pathological heart model, it shows that cardiac patches can restore a healthy blood flow. Conclusion We demonstrate that the devised computational modeling framework is capable of predicting characteristic trends (e.g. apex shortening, wall thickening and apex twisting) of a healthy heart, and that it can be used to study pathological hearts and external activation thereof. View on the web Inoreader. Take back control of your news feed. Follow us on Twitter and Facebook.

Gastric duplication cyst: a challenging EUS differential diagnosis between subepithelial gastric lesion and exophytic pancreatic cystic neoplasm—a case report and a literature review

xlomafota.13 shared this article with you from Inoreader Gastric duplication cyst: a challenging EUS differential diagnosis between subepithelial gastric lesion and exophytic pancreatic cystic neoplasm—a case report and a literature review Via Latest Results for Clinical Journal of Gastroenterology Abstract Gastric duplication cysts are rare congenital malformation with a potential neoplastic progression and they may represent a challenge in differential diagnosis with exophytic pancreatic cyst neoplasm. We describe a case of a 38-year old man, complaining of recurrent epigastric pain due to a large abdominal mass, referred to our Hospital for EUS evaluation. Differential diagnosis was between gastric duplication cyst and exophytic pancreatic cyst because of FNA pointed out amylase 1280 UI/L and CEA 593.33 ng/mL. Despite antibiotic prophylaxis, an overinfection of the lesion occurred after the FNA, likely due to the technical failure to drain the cyst completely. Afterwards, the patient was referred to surgery and the pathologist confirmed the diagnosis of gastric duplication cyst. In this setting, EUS procedure has gained a leading play, complementary to traditional imaging tests, although its role has been not yet standardized in the reported literature. Here , we describe and discuss our demanding case, and we propose an algorithm to simplify and standardize the diagnostic workup. View on the web Inoreader. Take back control of your news feed. Follow us on Twitter and Facebook.

Real-time eye state recognition using dual convolutional neural network ensemble

xlomafota.13 shared this article with you from Inoreader Real-time eye state recognition using dual convolutional neural network ensemble Via Latest Results for Journal of Real-Time Image Processing Abstract Automatic recognition of the eye states is essential for diverse computer vision applications related to drowsiness detection, facial emotion recognition (FER), human–computer interaction (HCI), etc. Existing solutions for eye state detection are either parameter intensive or suffer from a low recognition rate. This paper presents the design and implementation of a vision-based system for real-time eye state recognition on a resource-constrained embedded platform to tackle these issues. The designed system uses an ensemble of two lightweight convolutional neural networks (CNN), each trained to extract relevant information from the eye patches. We adopted transfer-learning-based fine-tuning to overcome the over-fitting issues when training the CNNs on small sample eye state datasets. Once trained, these CNNs are integrated and jointly fine-tuned to achieve enhanced performance. Experimental results manifest the effectiveness of the proposed eye state recognizer that is robust and computationally efficient. On the ZJU dataset, the proposed DCNNE model delivered the state-of-the-art recognition accuracy of 97.99% and surpassed the prior best recognition accuracy of 97.20% by 0.79%. The designed model also achieved competitive results on the CEW and MRL datasets. Finally, the designed CNNs are optimized and ported on two different embedded platforms for real-world applications with real-time performance. The complete system runs at 62 frames per second (FPS) on an Nvidia Xavier device and 11 FPS on a low-cost Intel NCS2 embedded platform using a frame size of 640 \(\times\) 480 pixels resolution. View on the web Inoreader. Take back control of your news feed. Follow us on Twitter and Facebook.

Microglia phenotypes are associated with subregional patterns of concomitant tau, amyloid-β and α-synuclein pathologies in the hippocampus of patients with Alzheimer’s disease and dementia with Lewy bodies

xlomafota.13 shared this article with you from Inoreader Microglia phenotypes are associated with subregional patterns of concomitant tau, amyloid-β and α-synuclein pathologies in the hippocampus of patients with Alzheimer's disease and dementia with Lewy bodies Via Latest Results for Acta Neuropathologica Communications Abstract The cellular alterations of the hippocampus lead to memory decline, a shared symptom between Alzheimer's disease (AD) and dementia with Lewy Bodies (DLB) patients. However, the subregional deterioration pattern of the hippocampus differs between AD and DLB with the CA1 subfield being more severely affected in AD. The activation of microglia, the brain immune cells, could play a role in its selective volume loss. How subregional microglia populations vary within AD or DLB and across these conditions remains poorly understood. Furthermore, how the nature of the hippocampal local pathological imprint is associated with microglia responses needs to be elucidated. To this purpose, we employed an automated pipeline for analysis of 3D confocal microscopy images to assess CA1, CA3 and DG/CA4 subfields microglia responses in post-mortem hippocampal samples from late-onset AD (n = 10), DLB (n = 8) and age-matched control (CTL) (n =� ��11) individuals. In parallel, we performed volumetric analyses of hyperphosphorylated tau (pTau), amyloid-β (Aβ) and phosphorylated α-synuclein (pSyn) loads. For each of the 32,447 extracted microglia, 16 morphological features were measured to classify them into seven distinct morphological clusters. Our results show similar alterations of microglial morphological features and clusters in AD and DLB, but with more prominent changes in AD. We identified two distinct microglia clusters enriched in disease conditions and particularly increased in CA1 and DG/CA4 of AD and CA3 of DLB. Our study confirms frequent concomitance of pTau, Aβ and pSyn loads across AD and DLB but reveals a specific subregional pattern for each type of pathology, along with a generally increased severity in AD. Furthermore, pTau and pSyn loads were highly correlated across subregions and conditions. We uncovered tight associations between microglial changes and the subfield pathological imprint. Our findi ngs suggest that combinations and severity of subregional pTau, Aβ and pSyn pathologies transform local microglia phenotypic composition in the hippocampus. The high burdens of pTau and pSyn associated with increased microglial alterations could be a factor in CA1 vulnerability in AD. View on the web Inoreader. Take back control of your news feed. Follow us on Twitter and Facebook.

Laser‐Assisted Sialolithotripsy: A Correlation of Objective and Subjective Outcomes

xlomafota13 shared this article with you from Inoreader Laser‐Assisted Sialolithotripsy: A Correlation of Objective and Subjective Outcomes Via The Laryngoscope Objective To analyze the long-term symptomatic results of laser-assisted sialolithotripsy (LAS) in cases of obstructive sialolithiasis and correlate with objective criteria using diagnostic sialendoscopy (DS) as a method of examination. Methods This is a retrospective study comprising 50 consecutive patients who underwent holmium-YAG LAS and completed follow-up of at least 6 months. Symptom scoring and endoscopic scoring were done at 6 weeks and 6 months intervals for further study purposes. Results At the end of 6 weeks post-LAS, 70% patients were asymptomatic (A-sym) and only 30% had residual symptoms (Sym). However, obstructed duct (OB-duct) was observed on endoscopic scoring in 88% due to stenosis, residual stones, or both stenosis and residual stones. The obstructed ducts were treated in outpatient clinic and followed up over time, leading to 98% of patients being in A-sym group at the end of study period of 6 months. At the end of study, 82% of patients had clear duct (CL-duct). Conclusion Holmium LAS is a viable option for the management of intermediate-sized stones. LAS if used judiciously, and in properly selected cases, has high rate of stone fragmentation and symptom resolution. A vigilant postoperative protocol taking into account residual mealtime symptoms and altered salivary characteristics combined with early DS can help identify and treat patients with residual stone fragments and ductal stenosis. Level of Evidence 3 Laryngoscope, 2022 View on the web Inoreader. Take back control of your news feed. Follow us on Twitter and Facebook.

Biodegradation of poly(L-lactic acid) and poly(epsilon-caprolactone) patches by human amniotic fluid in an in-vitro simulated fetal environment

xlomafota13 shared this article with you from Inoreader Biodegradation of poly(L-lactic acid) and poly(epsilon-caprolactone) patches by human amniotic fluid in an in-vitro simulated fetal environment Via leak of cerebrospinal fluid Sci Rep. 2022 Mar 10;12(1):3950. doi: 10.1038/s41598-022-07681-8. ABSTRACT Open spina bifida or myelomeningocele (MMC) is a devastating neurologic congenital defect characterized by primary failure of neural tube closure of the spinal column during the embryologic period. Cerebrospinal fluid leak caused by the MMC spinal defect in the developing fetus can result in a constellation of encephalic anomalies that include hindbrain herniation and hydrocephalus. The exposure of extruded spinal cord to amniotic fluid also poses a significant risk for inducing partial or complete paralysis of the body parts beneath the spinal aperture by progressive spinal cord damage in-utero. A randomized trial demonstrated that prenatal repair by fetal surgery, sometimes using patches, to cover the exposed spinal cord with a watertight barrier is effective in reducing the postnatal neurologic morbidity as evidenced by decreased incidence and severity of postnatal hydrocephalus and the reduced need for ventricular-peritoneal shunting. Currently, the use of inert or collagen-based patches are associated with high costs and inadequate structural properties. Specifically, the inert patches do not degrade after implantation, causing the need for a post-natal removal surgery associated with trauma for the newborn. Our present study is aimed towards in-vitro degradation studies of a newly designed patch, which potentially can serve as a superior alternative to existing patches for MMC repair. This novel patch was fabricated by blending poly(L-lactic acid) and poly(ε-caprolactone). The 16-week degradation study in amniotic fluid was focused on tracking changes in crystallinity and mechanical properties. An additional set of designed patches was exposed to phosphate-buffered saline (PBS), as a time-paired control. Crystallinity studies indicate the progress of hydrolytic degradation of the patch in both media, with a preference to bulk erosion in ph osphate buffered saline and surface erosion in amniotic fluid. Mechanical testing results establish that patch integrity is not compromised up to 16 weeks of exposure either to body fluids analog (PBS) or to amniotic fluid. PMID:35273223 | PMC:PMC8913814 | DOI:10.1038/s41598-022-07681-8 View on the web Inoreader. Take back control of your news feed. Follow us on Twitter and Facebook.

Local estrogen for nonsurgical recontouring of auricular cartilage

xlomafota13 shared this article with you from Inoreader Local estrogen for nonsurgical recontouring of auricular cartilage Via Journal of plastic, reconstructive & aesthetic surgery : JPRAS J Plast Reconstr Aesthet Surg. 2022 Feb 18:S1748-6815(22)00073-0. doi: 10.1016/j.bjps.2022.02.002. Online ahead of print. ABSTRACT INTRODUCTION: 5% of children are born with auricular deformities. Permanent recontouring can be achieved through splinting during early infancy. Beyond this time, splinting is ineffective, and patients require surgical correction. Neonatal cartilage malleability is hypothesized to be secondary to retained maternal estrogens, increasing hyaluronic acid concentration. In this article, we evaluate the efficacy of local estrogen treatments for the nonsurgical recontouring of mature auricular cartilage. METHODS: Ears of New Zealand rabbits were folded and splinted and then were randomly assigned to an experimental group, n = 10 (injected estrogen, topical estrogen, saline, or untreated). Treatment ears received injected estrogen or saline twice weekly or topical estrogen daily for 4 weeks. Two weeks post-t reatment, splints were removed, and ear angles were measured. Biopsies were taken for histologic and mechanical analysis, and systemic estrogen levels were assayed. RESULTS: Ear angles stabilized by 9 days post-splinting. Topical estrogen led to a significantly smaller resting angle (121.6° ± 13.5°) compared with saline and control (135.9° ± 11.2° and 145.3° ± 13.0°, respectively). Injected estrogen led to the most pronounced angle decrease (64.5° ± 35.3°). Ears injected with estrogen also showed a significant increase in cartilage thickness. Hyaluronic acid concentration was increased in both estrogen treatment groups compared with saline. At 3 weeks post-treatment, there was no significant differences in the elastic modulus of the cartilage or serum estrogen levels among the groups. CONCLUSION: Results show the potential result of local estrogen treatment to achieve a stable nonsurgical remodeling of mature auricular cartilage. Further study is needed to ev aluate the molecular mechanism and improve the transdermal estrogen delivery to optimize treatment regimen. PMID:35288037 | DOI:10.1016/j.bjps.2022.02.002 View on the web Inoreader. Take back control of your news feed. Follow us on Twitter and Facebook.