Blind source separation of ex-vivo aorta tissue multispectral images

Blind Source Separation methods (BSS) aim for the decomposition of a given signal in its main components or source signals. Those techniques have been widely used in the literature for the analysis of biomedical images, in order to extract the main components of an organ or tissue under study. The analysis of skin images for the extraction of melanin and hemoglobin is an example of the use of BSS. This paper presents a proof of concept of the use of source separation of ex-vivo aorta tissue multispectral Images. The images are acquired with an interference filter-based imaging system. The images are processed by means of two algorithms: Independent Components analysis and Non-negative Matrix Factorization. In both cases, it is possible to obtain maps that quantify the concentration of the main chromophores present in aortic tissue. Also, the algorithms allow for spectral absorbance of the main tissue components. Those spectral signatures were compared against the theoretical ones by using correlation coefficients. Those coefficients report values close to 0.9, which is a good estimator of the method’s performance. Also, correlation coefficients lead to the identification of the concentration maps according to the evaluated chromophore. The results suggest that Multi/hyper-spectral systems together with image processing techniques is a potential tool for the analysis of cardiovascular tissue.OCIS codes: (000.1430) Biology and medicine, (000.2170) Equipment and techniques, (110.4234) Multispectral and hyperspectral imaging, (170.3880) Medical and biological imaging, (170.4580) Optical diagnostics for medicine, (170.6935) Tissue characterization     

Cervical Osteophytes Increase the Risk for Foreign Body Impaction: A 171-Patient Case–Control Study

The aim of this study is to define the relationship between anatomical and pathological cervical structures and the impaction of ingested foreign bodies (FBs). The effects of such structures on deglutition have been previously discussed, however their contribution to FB impaction has not yet been examined. This was a retrospective case–control study of 171 patients who underwent computed tomography (CT) scans over the period 2008–2014: 57 patients with an esophageal or hypopharyngeal FB; the other 114 comprised the control group, selected using the ‘neighbor control’ method. CT scans were reviewed for measurements of cervical structures. The mean age was 63 ± 13 years and 55 ± 17 years in the case and control groups, respectively (p-value = 0.003). Age was the only demographic or clinical characteristic which demonstrated a significant difference. Overall, 24 patients had cervical osteophytes: 28 %(16) with an impacted FB, compared with 7 %(8) from the control group (p-value < 0.001). Of the patients with osteophytes and impacted FBs, 62.5 % had the FB lodged at a vertebral level corresponding to their osteophytes, while another 18.75 % had the FB within three vertebral levels above the osteophytes. Stepwise logistic regression revealed that osteophytes were a significant factor, independent of older age (p-value = 0.004). Adjusted odds ratio for FB impaction in the presence of osteophytes was 4.04. Ventral cervical osteophytes increase the risk for FB impaction in the upper digestive tract. This risk is independent of older age. These findings can be of value in preventive medicine, and emphasize the importance of looking for spinal changes in patients with recurrent FB impaction.     

Impact of age on surgical outcomes and failure rates in patients with thyroglossal duct cysts

PurposeThyroglossal duct cyst (TGDC) may appear in all age groups. The impact of age on surgical outcome has been reported with conflicting results. The aim of the study was to evaluate different risk factors for surgical success according to stratified age groups.MethodsA single center retrospective study. All patients who underwent a Sistrunk procedure between 2004 and 2018 were enrolled. Data included demographics, pre-operative presentation, intra\postoperative complications and surgical failures. Population groups were divided into adults (≥18 years), older children (OC, 3–18 years) and toddlers (<3 years).ResultsA total of 109 patients were included: 55 adults (50.5%), 36 OC (33%) and 18 toddlers (16.5%). The adult group demonstrated a significant lower rate of surgical failures when compared to the toddler (3.6%, vs. 38.9%, P < 0.001, respectively) and the OC group (3.6%, vs 16.7%, P = 0.032, respectively). A borderline significance was found when comparing surgical failure rates among toddlers and OC (38.9% vs.16.7%, P = 0.07, respectively). Post-operative complications were associated with surgical failures among toddlers (P = 0.045) and OC (P = 0.016), but not adults. Pre-operative infection and admission were significantly associated with failure in the OC group.ConclusionsSurgical failures following Sistrunk procedures and their associated risk factors vary between age groups. Familiarity with these rates and associations can contribute to better decision making in managing TGDC patients.     

Protective efficacy of a single immunization with capripoxvirus-vectored recombinant peste des petits ruminants vaccines in presence of pre-existing immunity

Sheeppox, goatpox and peste des petits ruminants (PPR) are highly contagious ruminant diseases widely distributed in Africa, the Middle East and Asia. Capripoxvirus (CPV)-vectored recombinant PPR vaccines (rCPV-PPR vaccines), which have been developed and shown to protect against both Capripox (CP) and PPR, would be critical tools in the control of these important diseases. In most parts of the world, these disease distributions overlap each other leaving concerns about the potential impact that pre-existing immunity against either disease may have on the protective efficacy of these bivalent rCPV-PPR vaccines. Currently, this question has not been indisputably addressed. Therefore, we undertook this study, under experimental conditions designed for the context of mass vaccination campaigns of small ruminants, using the two CPV recombinants (Kenya sheep-1 (KS-1) strain-based constructs) developed previously in our laboratory. Pre-existing immunity was first induced by immunization either with an attenuated CPV vaccine strain (KS-1) or the attenuated PPRV vaccine strain (Nigeria 75/1) and animals were thereafter inoculated once subcutaneously with a mixture of CPV recombinants expressing either the hemagglutinin (H) or the fusion (F) protein gene of PPRV (10³ TCID₅₀/animal of each). Finally, these animals were challenged with a virulent CPV strain followed by a virulent PPRV strain 3 weeks later. Our study demonstrated full protection against CP for vaccinated animals with prior exposure to PPRV and a partial protection against PPR for vaccinated animals with prior exposure to CPV. The latter animals exhibited a mild clinical form of PPR and did not show any post-challenge anamnestic neutralizing antibody response against PPRV. The implications of these results are discussed herein and suggestions made for future research regarding the development of CPV-vectored vaccines.     

Littoral cell angioma of the spleen

Littoral cell angiomas (LCAs) are rare splenic vascular neoplasms that arise from the cells lining the red pulp sinuses. The clinical course is benign and in most cases asymptomatic. However, as has been described in the literature, we have seen an association with malignant neoplasms and haematological disorders. The definitive diagnosis is made on histology and confirmed with immunohistochemistry. The use of percutaneous fine-needle aspiration biopsy (FNA) in preoperative diagnosis is controversial.     

Reinstatement of nicotine seeking is mediated by glutamatergic plasticity

Nicotine abuse and addiction is a major health liability. Nicotine, an active alkaloid in tobacco, is self-administered by animals and produces cellular adaptations in brain regions associated with drug reward, such as the nucleus accumbens. However, it is unknown whether, akin to illicit drugs of abuse such as cocaine or heroin, the adaptations endure and contribute to the propensity to relapse after discontinuing nicotine use. Using a rat model of cue-induced relapse, we made morphological and electrophysiological measures of synaptic plasticity, as well as quantified glutamate overflow, in the accumbens after 2 wk of withdrawal with extinction training. We found an enduring basal increase in dendritic spine head diameter and in the ratio of AMPA to NMDA currents in accumbens spiny neurons compared with yoked saline animals at 2 wk after the last nicotine self-administration session. This synaptic potentiation was associated with an increase in both AMPA (GluA1) and NMDA (GluN2A and GluN2B) receptor subunits, and a reduction in the glutamate transporter-1 (GLT-1). When nicotine seeking was reinstated by presentation of conditioned cues, there were parallel increases in behavioral responding, extracellular glutamate, and further increases in dendritic spine head diameter and ratio of AMPA to NMDA currents within 15 min. These findings suggest that targeting glutamate transmission might inhibit cue-induced nicotine seeking. In support of this hypothesis, we found that pharmacological inhibition of GluN2A with 3-Chloro-4-fluoro-N-[4-[[2-(phenylcarbonyl)hydrazino]carbonyl]benzyl]benzenesulfonamide (TCN-201) or GluN2B with ifenprodil abolished reinstated nicotine seeking. These results indicate that up-regulated GluN2A, GluN2B, and rapid synaptic potentiation in the accumbens contribute to cue-induced relapse to nicotine use.Tobacco smoking is the leading preventable cause of mortality, and relapse rates remain high (1, 2). Nicotine is a primary active alkaloid in tobacco and is generally recognized as being responsible for maintaining smoking behavior in humans (3). Accordingly, current smoking pharmacotherapy relies largely on replacing nicotinic receptor stimulation with compounds having pharmacokinetic and/or receptor efficacy characteristics that decrease nicotine craving without producing significant reward (4). Given the high rates of failure by replacement therapies, there is a pressing need to develop effective new medications targeting the neurological changes produced by cigarette use that underpin persistent relapse vulnerability.Nicotine self-administration results from activating α₄β₂ subunit-containing nicotinic cholinergic receptors localized on dopamine cell bodies in the ventral tegmental area and by stimulating presynaptic α₇-containing nicotinic acetylcholine receptors on glutamatergic afferents to dopamine neurons (5–7); the net consequence being increased dopamine release in the nucleus accumbens, a brain nucleus central to reward circuitry (8). In contrast to the well-understood synaptic physiology mediating the reinforcing properties of nicotine administration, the neuroadaptations underlying the enduring vulnerability to relapse produced by continued nicotine use are largely unknown. Studies examining brain tissue within 24 h after discontinuing nicotine self-administration reveal decreased accumbens proteins involved in glutamate signaling (9), including glial glutamate transport and presynaptic, release-regulating mGluR2/3 receptors (10). Thus, akin to other addictive drugs, such as cocaine, heroin, and alcohol, the enduring susceptibility to relapse to nicotine use may involve changes in accumbens glutamate transmission. However, it remains unexplored whether the nicotine-induced glutamatergic adaptations endure after more extended withdrawal, and whether they are required for nicotine relapse. For example, it is unclear whether rats withdrawn from nicotine self-administration share characteristics of altered spine morphology and synaptic strength seen after chronic cocaine or heroin administration (11, 12), or whether reinstating nicotine seeking further alters synaptic plasticity. Similarly, it is unknown whether there are enduring changes in extracellular glutamate as with withdrawal from cocaine (13) or in the glutamate receptors and transporters that regulate synaptic strength. Here we demonstrate that 2 wk after discontinuing nicotine self-administration there are enduring changes in glutamatergic synaptic physiology and morphology in the accumbens akin to what is produced by cocaine self-administration, and that further changes are elicited during cue-induced reinstatement of nicotine seeking [animal model of relapse (14)]. These changes in synaptic plasticity are associated with elevations in glutamate receptor subunits, and inhibiting GluN2A- or GluN2B-containing NMDA receptors abolished reinstated nicotine seeking.     

Outcome and survival following tracheostomy in patients ≥ 85 years old

European Archives of Oto-Rhino-Laryngology - To evaluate percutaneous dilatational tracheostomy in patients&nbsp;≥&nbsp;85&nbsp;years old: its complication rate and possible risk...     

Prognostic significance of granulomas in children with Crohn’s disease

Objectives: Granulomas have long been considered the histological hallmark of Crohn's disease (CD). Currently, there is considerable dispute with regards to their prognostic implications. We aimed to determine the effect of granulomas on phenotypic features and disease's long-term outcomes in a large cohort of pediatric CD patients.

Materials and methods: Medical records of pediatric CD patients diagnosed at the Schneider Children’s Medical Center were reviewed retrospectively. Patients were categorized into two groups based on the presence or absence of granulomas at diagnosis. Baseline characteristics included anthropometric, clinical, laboratory, radiological and endoscopic data. Outcome measures included flares, hospitalizations, biological therapy and surgery.

Results: Of 289?CD patients diagnosed between 2001 and 2015, 99 patients (34%) had granulomas. Median age of the entire cohort at diagnosis was 14.2 years (females, 42.6%), with a median follow-up of 8.5 years. Patients with granulomas had a significantly higher percentage (47.5% vs. 23.7%, p?=?.001) of upper gastrointestinal involvement and ileo-colonic disease (64.9% vs. 49.5%, p?=?.01). Extraintestinal manifestations were twice as common in patients without granulomas (16.3% vs. 8.1%, p?=?.05). Patients with granulomas were more likely to be hospitalized (HR =1.43, 95% CI: 1.0–2.0) and to receive biologic therapy (HR?=?1.52, 95% CI: 1.1–2.11). Additionally, both of these disease outcomes occurred significantly earlier (p?=?.013 and p?=?.027, respectively). In contrast, patients with granulomas did not exhibit increased risk of flares or bowel resection.

Conclusion: Patients with granulomas exhibited a distinct phenotype at diagnosis and demonstrated a more severe disease course.     

Humoral Response to the Pfizer BNT162b2 Vaccine in Patients Undergoing Maintenance Hemodialysis

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