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Noninvasive tracking of biochemical processes in the body is paramount in diagnostic medicine. Among the leading techniques is spectroscopic magnetic resonance imaging (MRI), which tracks metabolites with an amplified (hyperpolarized) magnetization signal injected into the subject just before scanning. Traditionally, the brief enhanced magnetization period of these agents limited clinical imaging. We propose a solution based on amalgamating two materials-one having diagnostic-metabolic activity and the other characterized by robust magnetization retention. This combination slows the magnetization decay in the diagnostic metabolic probe, which receives continuously replenished magnetization from the companion material. Thus, it extends the magnetization lifetime in some of our measurements to beyond 4 min, with net magnetization enhanced by more than four orders of magnitude. This could allow the metabolic probes to remain magnetized from injection until they reach the targeted organ, improving tissue signatures in clinical imaging. Upon validation, this metabolic MRI technique promises wide-ranging clinical applications, including diagnostic imaging, therapeutic monitoring, and posttreatment surveillance.
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Meios de Contraste , Imageamento por Ressonância Magnética , Imageamento por Ressonância Magnética/métodos , Meios de Contraste/química , Humanos , Animais , MagnetismoRESUMO
Pediatric brain tumors are the second most common type of cancer, accounting for one in four childhood cancer types. Brain tumor resection surgery remains the most common treatment option for brain cancer. While assessing tumor margins intraoperatively, surgeons must send tissue samples for biopsy, which can be time-consuming and not always accurate or helpful. Snapshot hyperspectral imaging (sHSI) cameras can capture scenes beyond the human visual spectrum and provide real-time guidance where we aim to segment healthy brain tissues from lesions on pediatric patients undergoing brain tumor resection. With the institutional research board approval, Pro00011028, 139 red-green-blue (RGB), 279 visible, and 85 infrared sHSI data were collected from four subjects with the system integrated into an operating microscope. A random forest classifier was used for data analysis. The RGB, infrared sHSI, and visible sHSI models achieved average intersection of unions (IoUs) of 0.76, 0.59, and 0.57, respectively, while the tumor segmentation achieved a specificity of 0.996, followed by the infrared HSI and visible HSI models at 0.93 and 0.91, respectively. Despite the small dataset considering pediatric cases, our research leveraged sHSI technology and successfully segmented healthy brain tissues from lesions with a high specificity during pediatric brain tumor resection procedures.
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BACKGROUND AND OBJECTIVES: Meticulous dissection and identification of nerves during head and neck surgery are crucial for preventing nerve damage. At present, nerve identification relies heavily on the surgeon's knowledge of anatomy, optionally combined with intraoperative neuromonitoring. Recently, optical techniques such as Mueller polarimetric imaging (MPI) have shown potential to improve nerve identification. STUDY DESIGN/MATERIALS AND METHODS: With institutional approval, seven 25-35 kg Yorkshire pigs underwent cervical incision in the central neck. Intraoperative images were obtained using our in-house MPI system. Birefringence maps from the MPI system were processed to quantify the values between 0 and 255 from different tissue types; an active contour model was applied to further improve nerve visualization on the corresponding color images. RESULTS: Among the seven pigs, the vagus nerves and recurrent laryngeal nerves were successfully differentiated with a mean intensity of 130.954 ± 20.611, which was significantly different (P < 0.05) from those of arteries (78.512 ± 27.78) and other surrounding tissues (82.583 ± 35.547). There were no imaging-related complications during the procedure. © 2021 Wiley Periodicals LLC. CONCLUSIONS: MPI is a potentially complementary intraoperative tool for nerve identification in adjacent tissues.
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Nervo Laríngeo Recorrente , Tireoidectomia , Animais , Estudos de Viabilidade , Pescoço/diagnóstico por imagem , Pescoço/cirurgia , SuínosRESUMO
PROBLEM: Antibody-mediated autoimmune diseases, such as autoimmune thyroid diseases (ATD), systemic lupus erythematosus (SLE), and antiphospholipid syndrome (APS), often are associated with recurrent fetal loss. One of the ATD is Hashimoto's thyroiditis which recently showed association with complications of pregnancy with increased levels of circulating autoantibodies reactive with epitopes on thyroid tissue such as thyroid peroxidase (anti-TPO). In retrospective study of sera analyses in patients with Hashimoto's thyroiditis, all patients had mainly elevated circulating anti-TPO autoantibodies. AIM: We assessed the potential of human anti-TPO highly positive IgG, derived from patients with Hashimoto's thyroiditis sera associated with complications of pregnancy, to cause directly complications of pregnancy in murine model. METHOD OF STUDY: Naïve ICR female mice, infused intravenously with 100 µg of anti-TPO-positive IgG, showed increased fetal loss and embryo small for date (P < .001) in comparison with mice passively transferred with commercial IgG or PBS. Moreover, we observed embryos small for date in the mice passively transferred with anti-TPO-positive IgG, exemplified by reduced weight of embryos and placentae (P = .001). Histopathological examination revealed delay in fetal development in 50% cases of anti-TPO-positive IgG-treated mice. Importantly, pathological changes in the transition zone, state of glycogen cells, and significant structural changes in the labyrinth part of placenta were observed in all anti-TPO-positive IgG samples. CONCLUSION: The current study shows in the first time, a direct proof of concept, on the association of human TPO-positive IgG from Hashimoto's thyroiditis patients on fetal loss induction in murine model.
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Autoanticorpos/imunologia , Autoantígenos/imunologia , Morte Fetal , Doença de Hashimoto/imunologia , Imunoglobulina G/imunologia , Iodeto Peroxidase/imunologia , Proteínas de Ligação ao Ferro/imunologia , Complicações na Gravidez/imunologia , Animais , Feminino , Doença de Hashimoto/sangue , Humanos , Camundongos Endogâmicos ICR , Placenta/patologia , GravidezRESUMO
BACKGROUND: Systemic-lupus-nephritis is a chronic autoimmune disease characterized by immune complex deposition and a flare of autoantibodies and leading to renal injury. OBJECTIVES: To expose anti-Dense-Fine-Speckled-70 (DFS70)-antibodies to genetically-prone-lupus-mice. METHODS: NZBXW/F1 female mice were monitored for the onset of glomerulonephritis by proteinuria upon infusion of anti-DFS70 (40 µg/mouse), commercial-human-IgG (cIgG) or phosphate-buffered-saline (PBS) as controls. The survival time was detected by mice death. Circulating anti-dsDNA were tested by ELISA. Proteinuria, was defined by a standard semi-quantitative-Bayer-Multistix-dipstick. Kidney histology was analyzed by periodic-acid-Schiff-PAS staining. RESULTS: A significantly higher percentage of anti-DFS70-infused mice exhibited prolonged survival time as compared with cIgG and PBS-subjected mice (p < 0.022). One mouse out of 10 mice injected with anti-DFS70-antibodies died at week 36, whereas, 6 out of 10 mice subjected with PBS found dead at this time. Eighty percent of anti-DFS70 injected mice did not show severe glomerulonephritis by histology. CONCLUSIONS: anti-DFS70 attenuated the progression of glomerulonephritis and prolonged the survival time. Circulating anti-DFS70-autoantibodies may confer a protective role against renal injury in murine-lupus-nephritis. Our data may propose a novel therapy approach for lupus patients.
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Anticorpos Antinucleares/imunologia , Glomerulonefrite/imunologia , Glomerulonefrite/patologia , Nefrite Lúpica/imunologia , Nefrite Lúpica/patologia , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Animais , Anticorpos Antinucleares/farmacologia , Modelos Animais de Doenças , Feminino , Rim/patologia , Camundongos , Camundongos Endogâmicos NZB , Proteinúria/imunologia , Proteinúria/patologia , Taxa de Sobrevida , Fatores de Transcrição/imunologiaRESUMO
BACKGROUND: Ferritin, the cellular protein storage for iron, has emerged as a key molecule in the immune system, orchestrating the cellular defense against inflammation. At the end of 2019, the novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) rapidly spread throughout China and other countries around the world, resulting in a viral pandemic. OBJECTIVES: To evaluate the correlation between ferritin and disease severity in coronavirus disease-2019 (COVID-19). METHODS: In this cross-sectional study, we obtained clinical and laboratory data regarding 39 hospitalized patients with confirmed COVID-19 from two hospitals in Israel. RESULTS: A significant increase in ferritin levels was demonstrated in patients with moderate and severe disease, compared to patients with mild disease (P = 0.006 and 0.005, respectively). Severe patients had significantly higher levels of ferritin (2817.6 ng/ml) than non-severe patients (708.6 ng/ml) P = 0.02. CONCLUSIONS: In this preliminary cross-sectional study, elevated ferritin levels were shown to correlate with disease severity in 39 patients from Israel with confirmed COVID-19 infection. Our results further strengthen the hypothesis that severe COVID-19 disease might be due to an underlying dysregulated hyperimmune response. In order to identify these patients early and prioritized resources, we believe that all patients with COVID-19 should be screened for hyperferritinemia.
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COVID-19/sangue , Ferritinas/sangue , Hiperferritinemia/sangue , Gravidade do Paciente , Adulto , Idoso , Biomarcadores/sangue , COVID-19/complicações , Estudos Transversais , Feminino , Humanos , Hiperferritinemia/virologia , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Adulto JovemRESUMO
Autoantibodies, which are antibodies that target self-epitopes, have considerable diagnostic, prognostic and predictive value in specific autoimmune diseases. Various infectious agents have been linked via numerous mechanisms to the formation of different autoantibodies. Therefore, estimating the prevalence of autoantibodies and anti-infectious antibodies in different populations is of high importance. Different genetic and environmental pressures, such as these found in Ghana's different geographical provinces, may affect the prevalence of autoantibodies. In this study, we assessed the seroprevalence of a diverse panel of autoantibodies and anti-infectious antibodies among the healthy Ghanaian population and investigated possible environmental and genetic predispositions for autoantibodies and autoimmunity. The sera of 406 healthy individuals were obtained from Greater Accra, Upper West, Eastern and Volta regions. Multiplexed assay and chemiluminescent immunoassay techniques were utilized to assess the presence of a panel of autoantibodies and anti-infectious antibodies. We found a high prevalence of anti-HSV-1 IgG (91-100%), anti-EBNA IgG (81-93%) and anti-EBV-VCA IgG (97-100%) antibodies. The prevalence of ANA (at least one of: anti-dsDNA; anti-chromatin; anti-ribosomal-P; anti-Ro/SSA; anti-La/SSB; anti-centromere B; anti-Sm; anti-Sm/RNP; anti-Scl-70; anti-Jo1; anti-DFS70) was estimated at 14%. An inverse association between anti-HSV-2 antibodies and ANA (p = 0.044; adjusted OR = 0.398; CI [0.162-0.975]) was found, after adjusting for differences in gender, age, and familial history of autoimmune diseases. A trend towards reduced seroprevalence of anti-dsDNA antibodies among subjects who were positive for anti-HSV-2 antibodies was also noted (p = 0.1). In conclusion, the inverse association between anti-HSV-2 antibodies and ANA positivity suggests a possible protective role of HSV-2 infection against autoimmunity.
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Anticorpos Antinucleares/sangue , Anticorpos Antifosfolipídeos/sangue , Anticorpos Antivirais/sangue , Doenças Autoimunes/epidemiologia , Infecções por Vírus Epstein-Barr/epidemiologia , Herpes Simples/epidemiologia , Adolescente , Adulto , Idoso , Doenças Autoimunes/imunologia , Infecções por Vírus Epstein-Barr/imunologia , Feminino , Gana , Herpes Simples/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Adulto JovemRESUMO
PURPOSE OF REVIEW: To summarize the recent data regarding Guillain-Barré syndrome (GBS) as an autoimmune disorder following infection with Zika virus (ZIKV) infection, including the proposed pathogenic mechanisms and the role of autoantibodies. RECENT FINDINGS: The loss of self-tolerance that leads to autoimmune diseases is a multifactorial process that may be illustrated as 'the mosaic of autoimmunity'. Infectious agents may contribute to the development of autoimmunity by several proposed mechanisms. One of the central mechanisms is molecular mimicry, which is also the most plausible mechanism in the case of ZIKV-induced autoimmune disorders.A recent meta-analysis found a low prevalence of GBS associated with ZIKV infection. Nevertheless, the estimated cost of illness for patients with GBS associated with ZIKV are tremendous and exceed 4.7 million dollars per year in Brazil alone. SUMMARY: Currently, there is sufficient data to indicate that ZIKV infection is one of many triggers and factors that may contribute to the development GBS. Thus, it is advised to evaluate and determine ZIKV exposure and infection in the management of potential GBS patients.
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Anticorpos Antivirais/imunologia , Autoimunidade , Síndrome de Guillain-Barré/etiologia , Tolerância Imunológica , Infecção por Zika virus/imunologia , Zika virus/imunologia , Síndrome de Guillain-Barré/imunologia , Humanos , Infecção por Zika virus/complicaçõesRESUMO
Dynamic nuclear polarization (DNP) for the enhancement of the NMR signals of specific metabolites has recently found applications in the context of magnetic resonance imaging (MRI). Currently, DNP signal enhancement is implemented in clinical systems through the use of exogenous stable organic free radicals, known as polarization agents (PAs), mixed in a solution with the metabolite of interest. These PAs are medically undesirable and thus must be filtered out prior to patient injection - a task that involves considerable technical complexity and consumes valuable time during which the polarization decays. Here, we aim to demonstrate DNP enhancements large enough for clinical relevance using a process free of exogenous PAs. This is achieved by processing (soft grinding) the metabolite in its solid form and subsequently exposing it to plasma in a dilute atmosphere to produce chemically-unstable free radicals (herein referred to as electrical-discharge-induced radicals - EDIRs) within the powder. These samples are then subjected to the normal DNP procedure of microwave irradiation while placed under a high static magnetic field, and their NMR signal is measured to quantify the enhancement of the protons' signal in the solid. Proton signal enhancements (measured as the ratio of the NMR signal with microwave irradiation to the NMR signal without microwave irradiation) of up to 150 are demonstrated in glucose. Upon fast dissolution, the free radicals are annihilated, leaving the sample in its original chemical composition (which is safe for clinical use) without any need for filtration and cumbersome quality control procedures. We thus conclude that EDIRs are found to be highly efficient in providing DNP enhancement levels that are on par with those achieved with the exogenous PAs, while being safe for clinical use. This opens up the possibility of applying our method to clinical scenarios with minimal risks and lower costs per procedure.
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Glucose/química , Espectroscopia de Ressonância Magnética , Gases em Plasma/química , Prótons , PósAssuntos
Anticorpos Antinucleares/imunologia , Canabidiol/farmacologia , Fatores Imunológicos/farmacologia , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Proteinúria/tratamento farmacológico , Animais , Modelos Animais de Doenças , Progressão da Doença , Feminino , Humanos , Lúpus Eritematoso Sistêmico/fisiopatologia , Camundongos , Camundongos Endogâmicos NZB , Proteinúria/etiologia , Análise de SobrevidaRESUMO
BACKGROUND: Previously described as a subcategory of obsessive compulsive disorder (OCD), hoarding disorder was added to the fifth Diagnostic and Statistical Manual of Mental Disorders (DSM-V) as a stand-alone diagnosis for the first time. The first formal research in the 1990s surprisingly found no connection between material deprivation early in life and hoarding; however, later studies linked early traumatic life experiences with hoarding. Subsequent familial studies demonstrated a genetic predisposition for hoarding. Emerging evidence suggests a link between a post-traumatic stress disorder (PTSD) and hoarding in Jewish Holocaust survivors. OBJECTIVES: To evaluate the literature on PTSD among Jewish Holocaust survivors for associations between PTSD and hoarding. METHODS: A systematic search of selected databases, including PubMed, Google Scholar, NCBI, Psych Info, and EBSCO Host was conducted from 1 March 2017 to 15 July 2018 using the following search terms: hoarding, hoarding disorder, obsessive compulsive disorder, OCD, compulsive hoarding, Jewish Holocaust survivors, Shoa, post-traumatic stress disorder, and PTSD. Inclusion criteria included peer reviewed research published on adults in English since 1990. Because no publications linking hoarding and PTSD in Jewish Holocaust survivors were found, references in retained papers were also searched for any relevant published work. RESULTS: Seven articles linking PTSD and hoarding were identified for this review. However, no articles were found linking PTSD and hoarding in Jewish Holocaust survivors. CONCLUSIONS: A relationship between PTSD and hoarding in Jewish Holocaust survivors is conceivable and should be explored to effectively diagnose and care for affected individuals.
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Colecionismo/epidemiologia , Holocausto/psicologia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Sobreviventes/psicologia , Bases de Dados Factuais , Colecionismo/psicologia , Humanos , Judeus/psicologia , Modelos Teóricos , Transtorno Obsessivo-Compulsivo/epidemiologia , Transtorno Obsessivo-Compulsivo/psicologia , Projetos de Pesquisa , Transtornos de Estresse Pós-Traumáticos/psicologiaRESUMO
Dynamic nuclear polarization (DNP) is a method for enhancing nuclear magnetic resonance (NMR) signals that has many potential applications in chemistry and medicine. Traditionally, DNP signal enhancement is achieved through the use of exogenous radicals mixed in a solution with the molecules of interest. Here we show that proton DNP signal enhancements can be obtained for solid samples without the use of solvent and exogenous radicals. Radicals are generated primarily on the surface of a solid sample using electrical discharges. These radicals are found suitable for DNP. They are stable under moderate vacuum conditions, yet readily annihilate upon compound dissolution or air exposure. This feature makes them attractive for use in medical applications, where the current variety of radicals used for DNP faces regulatory problems. In addition, this solvent-free method may be found useful for analytical NMR of solid samples which cannot tolerate solvents, such as certain pharmaceutical products.
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Radicais Livres/química , Ressonância Magnética Nuclear Biomolecular/métodos , Química Farmacêutica , Campos Eletromagnéticos , Espectroscopia de Ressonância de Spin Eletrônica , Manose/química , Prótons , Dióxido de Silício/química , Solubilidade , Solventes , Sacarose/químicaRESUMO
The in-operando detection and high resolution spatial imaging of paramagnetic defects, impurities, and states becomes increasingly important for understanding loss mechanisms in solid-state electronic devices. Electron spin resonance (ESR), commonly employed for observing these species, cannot meet this challenge since it suffers from limited sensitivity and spatial resolution. An alternative and much more sensitive method, called electrically-detected magnetic resonance (EDMR), detects the species through their magnetic fingerprint, which can be traced in the device's electrical current. However, until now it could not obtain high resolution images in operating electronic devices. In this work, the first spatially-resolved electrically-detected magnetic resonance images (EDMRI) of paramagnetic states in an operating real-world electronic device are provided. The presented method is based on a novel microwave pulse sequence allowing for the coherent electrical detection of spin echoes in combination with powerful pulsed magnetic-field gradients. The applicability of the method is demonstrated on a device-grade 1-µm-thick amorphous silicon (a-Si:H) solar cell and an identical device that was degraded locally by an electron beam. The degraded areas with increased concentrations of paramagnetic defects lead to a local increase in recombination that is mapped by EDMRI with â¼20-µm-scale pixel resolution. The novel approach presented here can be widely used in the nondestructive in-operando three-dimensional characterization of solid-state electronic devices with a resolution potential of less than 100 nm.
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A new method for obtaining an NMR signal in the Earth's magnetic field (EF) is presented. The method makes use of a simple pulse sequence with only DC fields which is much less demanding than previous approaches in terms of the pulses' rise and fall times. Furthermore, it offers the possibility of obtaining NMR data with enough spectral resolution to allow retrieving high resolution molecular chemical shift (CS) information - a capability that was not considered possible in EF NMR until now. Details of the pulse sequence, the experimental system, and our specially tailored EF NMR probe are provided. The experimental results demonstrate the capability to differentiate between three types of samples made of common fluorine compounds, based on their CS data.