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1.
Anal Biochem ; 689: 115500, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38431139

RESUMO

Early detection of the coronavirus is acknowledged as a crucial measure to mitigate the spread of the pandemic, facilitating timely isolation of infected individuals, and disrupting the transmission chain. In this study, we leveraged the properties of synthesized Ag-MOF, including high porosity and increased flow intensity. Electrochemical techniques such as cyclic voltammetry (CV) and differential pulse voltammetry (DPV) were employed to develop an economical and portable sensor with exceptional selectivity for COVID-19 detection. The methodology involves the deposition of Ag-MOF onto the surface of a Glassy Carbon Electrode (GCE), which resulted in a progressive augmentation of electric current. Subsequently, the targeted antibodies were applied, and relevant tests were conducted. The sensor demonstrated the capacity to detect the virus within a linear range of 100 fM to 10 nM, boasting a noteworthy Limit of Detection (LOD) of 60 fM. The entire detection process could be completed in a brief duration of 20 min, exhibiting high levels of accuracy and precision, outperforming comparable techniques in terms of speed and efficacy.


Assuntos
Técnicas Biossensoriais , COVID-19 , Humanos , Técnicas Biossensoriais/métodos , COVID-19/diagnóstico , Imunoensaio , Carbono/química , Anticorpos , Técnicas Eletroquímicas/métodos , Eletrodos
2.
Mikrochim Acta ; 191(7): 419, 2024 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916771

RESUMO

A method is presented for chemiluminescence resonance energy transfer (CRET) using APTES-Fe3O4 as a highly efficient energy acceptor with strong magnetic effectiveness over extended distances, while an Au@BSA-luminol composite acts as the donor. In order to boost the chemiluminescence reactions, CuO nanoparticles were successfully employed. The distance between the donor and acceptor is a crucial factor in the occurrence of the CRET phenomenon. A sensitive and high-throughput sandwich chemiluminescence immunosensor has been developed accordingly with a linear range of 1.0 × 10-7 g/L to 6.0 × 10-5 g/L and a limit of detection of 0.8 × 10-7 g/L. The CRET-based sandwich immunosensor has the potential to be implemented to early cancer diagnosis because of its high sensitivity in detecting Nanog, fast analysis (30 min), and simplicity. Furthermore, this approach has the potential to be adapted for the recognition of other antigen-antibody immune complexes by utilizing the corresponding antigens and their selective antibodies.


Assuntos
Biomarcadores Tumorais , Proteína Homeobox Nanog , Humanos , Imunoensaio/métodos , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/imunologia , Biomarcadores Tumorais/análise , Proteína Homeobox Nanog/imunologia , Células-Tronco Neoplásicas/imunologia , Limite de Detecção , Medições Luminescentes/métodos , Cobre/química , Anticorpos Imobilizados/imunologia , Ouro/química , Técnicas Biossensoriais/métodos , Nanopartículas Metálicas/química
3.
Neurol Sci ; 44(8): 2903-2914, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36914833

RESUMO

PURPOSE: Task-based BOLD fMRI and DTI-fiber tracking have become part of the routine presurgical work-up of brain tumor patients in many institutions. However, their potential impact on both surgical treatment and neurologic outcome remains unclear, in despite of the high costs and complex implementation. METHODS: We retrospectively investigated whether performing fMRI and DTI-ft preoperatively substantially impacted surgical planning and patient outcome in a series of brain tumor patients. We assessed (i) the quality of fMRI and DTI-ft results, by using a scale of 0-2 (0 = failed mapping; 1 = intermediate confidence; 2 = good confidence), (ii) whether functional planning substantially contributed to defining the surgical strategy to be undertaken (i.e., no surgery, biopsy, or resection, with or without ESM), the surgical entry point and extent of resection, and (iii) the incidence of neurological deficits post-operatively. RESULTS: Twenty-seven patients constituted the study population. The mean confidence rating was 1.9/2 for fMRI localization of the eloquent cortex and lateralization of the language function and 1.7/2 for DTI-ft results. Treatment strategy was altered in 33% (9/27) of cases. Surgical entry point was modified in 8% (2/25) of cases. The extent of resection was modified in 40% (10/25). One patient (1/25, 4%) developed one new functional deficit post-operatively. CONCLUSION: Functional MR mapping - which must not be considered an alternative to ESM - has a critical role preoperatively, potentially modifying treatment strategy or increasing the neurosurgeons' confidence in the surgical approach hypothesized based on conventional imaging.


Assuntos
Neoplasias Encefálicas , Imageamento por Ressonância Magnética , Humanos , Estudos Retrospectivos , Imagem de Tensor de Difusão/métodos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Neoplasias Encefálicas/patologia , Idioma , Mapeamento Encefálico/métodos
4.
Crit Care ; 26(1): 35, 2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-35130953

RESUMO

INTRODUCTION: Brain multimodal monitoring including intracranial pressure (ICP) and brain tissue oxygen pressure (PbtO2) is more accurate than ICP alone in detecting cerebral hypoperfusion after traumatic brain injury (TBI). No data are available for the predictive role of a dynamic hyperoxia test in brain-injured patients from diverse etiology. AIM: To examine the accuracy of ICP, PbtO2 and the oxygen ratio (OxR) in detecting regional cerebral hypoperfusion, assessed using perfusion cerebral computed tomography (CTP) in patients with acute brain injury. METHODS: Single-center study including patients with TBI, subarachnoid hemorrhage (SAH) and intracranial hemorrhage (ICH) undergoing cerebral blood flow (CBF) measurements using CTP, concomitantly to ICP and PbtO2 monitoring. Before CTP, FiO2 was increased directly from baseline to 100% for a period of 20 min under stable conditions to test the PbtO2 catheter, as a standard of care. Cerebral monitoring data were recorded and samples were taken, allowing the measurement of arterial oxygen pressure (PaO2) and PbtO2 at FiO2 100% as well as calculation of OxR (= ΔPbtO2/ΔPaO2). Regional CBF (rCBF) was measured using CTP in the tissue area around intracranial monitoring by an independent radiologist, who was blind to the PbtO2 values. The accuracy of different monitoring tools to predict cerebral hypoperfusion (i.e., CBF < 35 mL/100 g × min) was assessed using area under the receiver-operating characteristic curves (AUCs). RESULTS: Eighty-seven CTPs were performed in 53 patients (median age 52 [41-63] years-TBI, n = 17; SAH, n = 29; ICH, n = 7). Cerebral hypoperfusion was observed in 56 (64%) CTPs: ICP, PbtO2 and OxR were significantly different between CTP with and without hypoperfusion. Also, rCBF was correlated with ICP (r = - 0.27; p = 0.01), PbtO2 (r = 0.36; p < 0.01) and OxR (r = 0.57; p < 0.01). Compared with ICP alone (AUC = 0.65 [95% CI, 0.53-0.76]), monitoring ICP + PbO2 (AUC = 0.78 [0.68-0.87]) or ICP + PbtO2 + OxR (AUC = 0.80 (0.70-0.91) was significantly more accurate in predicting cerebral hypoperfusion. The accuracy was not significantly different among different etiologies of brain injury. CONCLUSIONS: The combination of ICP and PbtO2 monitoring provides a better detection of cerebral hypoperfusion than ICP alone in patients with acute brain injury. The use of dynamic hyperoxia test could not significantly increase the diagnostic accuracy.


Assuntos
Lesões Encefálicas Traumáticas , Hiperóxia , Encéfalo/diagnóstico por imagem , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Circulação Cerebrovascular , Humanos , Pressão Intracraniana , Pessoa de Meia-Idade , Oxigênio
5.
Eur J Nucl Med Mol Imaging ; 48(6): 1890-1901, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33398411

RESUMO

OBJECTIVES: Sudden loss of smell is a very common symptom of coronavirus disease 19 (COVID-19). This study characterizes the structural and metabolic cerebral correlates of dysosmia in patients with COVID-19. METHODS: Structural brain magnetic resonance imaging (MRI) and positron emission tomography with [18F]-fluorodeoxyglucose (FDG-PET) were prospectively acquired simultaneously on a hybrid PET-MR in 12 patients (2 males, 10 females, mean age: 42.6 years, age range: 23-60 years) with sudden dysosmia and positive detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on nasopharyngeal swab specimens. FDG-PET data were analyzed using a voxel-based approach and compared with that of a group of healthy subjects. RESULTS: Bilateral blocking of the olfactory cleft was observed in six patients, while subtle olfactory bulb asymmetry was found in three patients. No MRI signal abnormality downstream of the olfactory tract was observed. Decrease or increase in glucose metabolism abnormalities was observed (p < .001 uncorrected, k ≥ 50 voxels) in core olfactory and high-order neocortical areas. A modulation of regional cerebral glucose metabolism by the severity and the duration of COVID-19-related dysosmia was disclosed using correlation analyses. CONCLUSIONS: This PET-MR study suggests that sudden loss of smell in COVID-19 is not related to central involvement due to SARS-CoV-2 neuroinvasiveness. Loss of smell is associated with subtle cerebral metabolic changes in core olfactory and high-order cortical areas likely related to combined processes of deafferentation and active functional reorganization secondary to the lack of olfactory stimulation.


Assuntos
Anosmia , COVID-19 , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , SARS-CoV-2 , Olfato , Tomografia Computadorizada por Raios X , Adulto Jovem
6.
Appl Opt ; 60(2): 367-374, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33448960

RESUMO

The development of random lasers (RLs) is attracting considerable interest. Here, we investigate how the nonlinear optical behaviors of scattering particles can affect the emission of RLs. In this regard, molybdenum oxide is synthesized by the electrodeposition method, and its nonlinear optical properties are measured using the Z-scan technique. Then, to study the nonlinear effects on RL emission, we insert molybdenum oxide in a conventional RL. It was observed that the emitted intensity enhanced for samples with a positive sign of nonlinear refractive index, while intensity degraded for samples with a negative refractive index. Our results show that both the sign and magnitude of the nonlinear refractive index can modify the intensity of RL emission at pump energies enough above the threshold.

7.
J Stroke Cerebrovasc Dis ; 29(5): 104684, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32151477

RESUMO

INTRODUCTION: Intracranial vasculopathies easily elude classic stroke work-up. We aim in this work to show that vessel wall-MRI could prove an efficient alternative to digital subtraction angiography for the diagnosis of intracranial vasculopathies by identifying intracranial arterial vessel walls anomalies and contrast enhancement, suggestive of angiitis of the central nervous system. MATERIALS AND METHODS: Clinical and imaging characteristics of stroke patients diagnosed with primary angiitis of the central nervous system based on vessel wall-MRI were retrospectively reviewed and the clinical and imaging features of angiitis associated with intracranial vessel walls anomalies and contrast enhancement detailed. RESULTS: Twenty patients were included (mean age was 59 years old). All patients were admitted for focal neurological deficits of sudden onset that were recurrent in 13 subjects. Cognitive impairment, headache and seizures occurred in, respectively, 13, 5, and 2 patients. Cerebrospinal fluid analysis was abnormal in 15 patients. In MRI, FLAIR sequences showed ischemic infarcts in 20 patients and DWI showed acute infarct in 15 patients. Digital subtraction angiography was performed in 11 patients and disclosed proximal and distal multifocal stenosis in 10 patients along distal irregularities in different vascular territories in 7. For all of our patients, VW-MRI revealed a concentric contrast enhancement of arterial walls, localized in multiple vascular territories, suggesting angiitis. Abnormalities on digital subtraction angiography and/or MR-Angiography, and vessel wall-MRI were consistent in all patients. CONCLUSIONS: This report underlies the added value of vessel wall-MRI to the diagnosis of underlying intracranial vasculopathy, particularly primary angiitis of the central nervous system, without the use of invasive endovascular techniques and the yield of vessel wall-MRI in the work-up of cryptogenic stroke.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Artérias Cerebrais/diagnóstico por imagem , Imageamento por Ressonância Magnética , Acidente Vascular Cerebral/diagnóstico por imagem , Vasculite do Sistema Nervoso Central/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Digital , Isquemia Encefálica/etiologia , Isquemia Encefálica/fisiopatologia , Angiografia Cerebral , Artérias Cerebrais/efeitos dos fármacos , Artérias Cerebrais/fisiopatologia , Feminino , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/fisiopatologia , Resultado do Tratamento , Vasculite do Sistema Nervoso Central/complicações , Vasculite do Sistema Nervoso Central/tratamento farmacológico , Vasculite do Sistema Nervoso Central/fisiopatologia
8.
Ann Neurol ; 83(2): 283-294, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29328521

RESUMO

OBJECTIVES: In multiple sclerosis (MS), magnetic resonance imaging (MRI) is a sensitive tool for detecting white matter lesions, but its diagnostic specificity is still suboptimal; ambiguous cases are frequent in clinical practice. Detection of perivenular lesions in the brain (the "central vein sign") improves the pathological specificity of MS diagnosis, but comprehensive evaluation of this MRI biomarker in MS-mimicking inflammatory and/or autoimmune diseases, such as central nervous system (CNS) inflammatory vasculopathies, is lacking. In a multicenter study, we assessed the frequency of perivenular lesions in MS versus systemic autoimmune diseases with CNS involvement and primary angiitis of the CNS (PACNS). METHODS: In 31 patients with inflammatory CNS vasculopathies and 52 with relapsing-remitting MS, 3-dimensional T2*-weighted and T2-fluid-attenuated inversion recovery images were obtained during a single MRI acquisition after gadolinium injection. For each lesion, the central vein sign was evaluated according to consensus guidelines. For each patient, lesion count, volume, and brain location, as well as fulfillment of dissemination in space MRI criteria, were assessed. RESULTS: MS showed higher frequency of perivenular lesions (median = 88%) than did inflammatory CNS vasculopathies (14%), without overlap between groups or differences between 3T and 1.5T MRI. Among inflammatory vasculopathies, Behçet disease showed the highest median frequency of perivenular lesions (34%), followed by PACNS (14%), antiphospholipid syndromes (12%), Sjögren syndrome (11%), and systemic lupus erythematosus (0%). When a threshold of 50% perivenular lesions was applied, central vein sign discriminated MS from inflammatory vasculopathies with a diagnostic accuracy of 100%. INTERPRETATION: The central vein sign differentiates inflammatory CNS vasculopathies from MS at standard clinical magnetic field strengths. Ann Neurol 2018;83:283-294.


Assuntos
Encéfalo/patologia , Esclerose Múltipla Recidivante-Remitente/patologia , Vasculite do Sistema Nervoso Central/patologia , Adulto , Idoso , Encéfalo/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Neuroimagem/métodos , Vasculite do Sistema Nervoso Central/diagnóstico por imagem , Adulto Jovem
9.
Neuroradiology ; 60(12): 1287-1295, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30219936

RESUMO

PURPOSE: To evaluate the ability of dual-energy CT angiography (DECTA) in metal artifact reduction in patients with treated intracranial aneurysms by comparing DECTA-based virtual monoenergetic extrapolations (VMEs) and mixed images (MI). METHODS: Thirty-five patients underwent prospectively a dual-source DECTA (Somatom Force, Siemens Medical Solutions, Forchheim, Germany) after aneurysm repair. A total number of 40 aneurysms (23 treated by coil embolization and 17 treated by surgical clipping) were analyzed. Mixed images (equivalent to a conventional single-energy CT angiography) were compared to VMEs at 75, 95, and 115 keV. Artifact severity was assessed quantitatively by measuring the mean attenuation value and standard deviation within regions of interest placed in the most hypodense coil or clip artifact area. Artifact severity score and contrast vessel score were also assessed qualitatively by two independent blinded readers. RESULTS: In those aneurysms treated by surgical clipping, quantitative and qualitative analyses showed significant reduction of artifacts on VMEs compared to MI with the best compromise being obtained at 95 keV in order to keep an optimal vessel contrast in the adjacent vessel. In those aneurysms treated by coil embolization, there was no significant reduction of artifacts both on quantitative and qualitative analyses. CONCLUSION: Dual-source DECTA was helpful in order to reduce clip artifacts on VMEs with the optimal adjacent vessel visualization obtained at 95 keV, whereas this technique was not helpful in aneurysms treated by coiling.


Assuntos
Prótese Vascular , Angiografia por Tomografia Computadorizada/métodos , Procedimentos Endovasculares/instrumentação , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/terapia , Adulto , Idoso , Algoritmos , Artefatos , Embolização Terapêutica/instrumentação , Feminino , Humanos , Masculino , Metais , Pessoa de Meia-Idade , Estudos Prospectivos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Stents
10.
Clin Neurophysiol ; 163: 90-101, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38714152

RESUMO

OBJECTIVE: To investigate cortical oscillations during a sentence completion task (SC) using magnetoencephalography (MEG), focusing on the semantic control network (SCN), its leftward asymmetry, and the effects of semantic control load. METHODS: Twenty right-handed adults underwent MEG while performing SC, consisting of low cloze (LC: multiple responses) and high cloze (HC: single response) stimuli. Spectrotemporal power modulations as event-related synchronizations (ERS) and desynchronizations (ERD) were analyzed: first, at the whole-brain level; second, in key SCN regions, posterior middle/inferior temporal gyri (pMTG/ITG) and inferior frontal gyri (IFG), under different semantic control loads. RESULTS: Three cortical response patterns emerged: early (0-200 ms) theta-band occipital ERS; intermediate (200-700 ms) semantic network alpha/beta-band ERD; late (700-3000 ms) dorsal language stream alpha/beta/gamma-band ERD. Under high semantic control load (LC), pMTG/ITG showed prolonged left-sided engagement (ERD) and right-sided inhibition (ERS). Left IFG exhibited heightened late (2500-2550 ms) beta-band ERD with increased semantic control load (LC vs. HC). CONCLUSIONS: SC involves distinct cortical responses and depends on the left IFG and asymmetric engagement of the pMTG/ITG for semantic control. SIGNIFICANCE: Future use of SC in neuromagnetic preoperative language mapping and for understanding the pathophysiology of language disorders in neurological conditions.


Assuntos
Magnetoencefalografia , Semântica , Humanos , Masculino , Feminino , Adulto , Magnetoencefalografia/métodos , Córtex Cerebral/fisiologia , Adulto Jovem
11.
Clin Neuroradiol ; 34(2): 475-483, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38386051

RESUMO

BACKGROUND AND PURPOSE: Cerebral vasospasm (CV) following aneurysmal subarachnoid hemorrhage (aSAH) may lead to morbidity and mortality. Endovascular mechanical angioplasty may be performed if symptomatic CV is refractory to noninvasive medical management. Off-label compliant remodelling balloons tend to conform to the course of the vessel, contrary to noncompliant or semi-compliant balloons. Our objective is to describe our initial experience with the semi-compliant Neurospeed balloon (approved for intracranial stenosis) in cerebral vasospasm treatment following aSAH. METHODS: All patients included in the prospective observational SAVEBRAIN PWI (NCT05276934 on clinicaltrial.gov) study who underwent cerebral angioplasty using the Neurospeed balloon for the treatment of medically refractory and symptomatic CV after aSAH were identified. Patient demographic information, procedural details and outcomes were obtained from electronic medical records. RESULTS: Between February 2022 and June 2023, 8 consecutive patients underwent CV treatment with the Neurospeed balloon. Angioplasty of 48 arterial segments (supraclinoid internal carotid artery, A1 and A2 segments of the anterior cerebral artery, M1 and M2 segments of the middle cerebral artery) was attempted and 44/48 (92%) were performed. The vessel diameter significantly improved following angioplasty (+81%), while brain hypoperfusion decreased (-81% of the mean TMax). There was no long-term clinical complication, 4% periprocedural complications occurred. CONCLUSION: The semi-compliant Neurospeed balloon is effective in the treatment of cerebral vasospasm following aSAH, bringing a new device into the armamentarium of the neurointerventionalist to perform intracranial angioplasty.


Assuntos
Angioplastia com Balão , Hemorragia Subaracnóidea , Vasoespasmo Intracraniano , Humanos , Vasoespasmo Intracraniano/etiologia , Vasoespasmo Intracraniano/terapia , Vasoespasmo Intracraniano/diagnóstico por imagem , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/terapia , Feminino , Masculino , Pessoa de Meia-Idade , Angioplastia com Balão/métodos , Estudos Prospectivos , Idoso , Adulto , Resultado do Tratamento , Angiografia Cerebral
12.
Avicenna J Med Biotechnol ; 15(1): 14-20, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36789121

RESUMO

Background: WWTR1 or TAZ is a transcriptional co-activator protein expressed in cytoplasm which functions as the main downstream effector of the Hippo signaling pathway. This pathway is an evolutionally conserved signal cascade, which plays a pivotal role in organ size control and tumorigenesis. Ectopic expression of TAZ has already been observed in many malignancies, while the ectopic localization of TAZ is reported for the first time. The aim of this study was to produce a specific monoclonal antibody (mAb) against a synthetic peptide derived from WWTR1 protein to be used as a research tool in human carcinomas. Methods: A 21-mer synthetic peptide (derived from human TAZ protein) was used for immunization of BALB/c mice after conjugation with Keyhole Limpet Haemocyanin (KLH) using hybridoma technology. The generated mAb reacted with the immunizing peptide employing ELISA assay. The reactivity of the antibody with native TAZ protein was assessed through Western blot, immunocytochemistry, and flow cytometry using different cancer cell lines. Results: The produced mAb could recognize the immunizing peptide in ELISA and Kaff was 0.6×10-9 M. The produced anti-TAZ mAb unlike available commercial anti-TAZ antibody, was capable of specifically recognizing cell surface TAZ in human carcinoma cell lines including MCF-7, Raji, and A431 in Western blot, immunocytochemistry, and flow cytometry assays. As expected, no reactivity was observed using normal Peripheral Blood Mononuclear Cell (PBMC) from healthy donors. Conclusion: Based on the results, TAZ is ectopically expressed on the surface of tumor cell lines which is not the case in normal cells. The generated mAb has a potential to be used as a research tool in studying the expression of TAZ in human carcinomas in different applications.

13.
Avicenna J Med Biotechnol ; 15(2): 68-75, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37034891

RESUMO

Background: Vimentin is a prominent Intermediate Filaments (IFs) protein expressed in different mesenchymal origin cell types. Besides a wide range of cellular function roles associated with vimentin expression, its dysregulation and cell surface expression in the induction of malignancy properties have been reported extensively, making it a promising cancer-specific target. Therefore, this study aimed to generate and characterize anti-vimentin monoclonal antibodies. Methods: A 14-mer synthetic peptide from vimentin was conjugated to Keyhole Limpet Hemocyanin (KLH) and used for immunization of Blab/C mice and monoclonal production by conventional hybridoma technology. The monoclonal antibody was purified using affinity chromatography of supernatants from the selected hybridoma cells. ELISA, Immunoprecipitation-Western blotting (IP-WB), Immunocytochemistry (ICC), and flow cytometry were employed to characterize the produced monoclonal antibody in terms of interaction with vimentin immunizing peptide as well as vimentin protein. Results: Amid the several obtained producing anti-vimentin antibody hybridomas, the 7C11-D9 clone (IgG1 isotype with kappa light chain) showed higher reactivity with the immunizing peptide, and led to its selection for purification and characterization. The purified antibody could detect vimentin protein in IP-WB, ICC and flow cytometry of the normal and cancerous cells with different origin. No vimentin expression was found in normal healthy Peripheral Blood Mononuclear Cell (PBMC). Conclusion: Taken together, 7C11-D9 anti-vimentin monoclonal antibody might be used as immune diagnostic or immune therapeutic tool where detection or targeting of vimentin in a wide range of organisms is required.

14.
Tissue Cell ; 81: 101996, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36657256

RESUMO

In the development of vascular tissue engineering, particularly in the case of small diameter vessels, one of the key obstacles is the blockage of these veins once they enter the in vivo environment. One of the contributing factors to this problem is the aberrant proliferation and migration of vascular smooth muscle cells (VSMCs) from the media layer of the artery to the interior of the channel. Two distinct phenotypes have been identified for smooth muscle cells, namely synthetic and contractile. Since the synthetic phenotype plays an essential role in the unusual growth and migration, the aim of this study was to convert the synthetic phenotype into the contractile one, which is a solution to prevent the abnormal growth of VSMCs. To achieve this goal, these cells were subjected to electrical signals, using a 1000 µA sinusoidal stimulation at 10 Hz for four days, with 20 min duration per 24 h. The morphological transformations and changes in the expression of vimentin, nestin, and ß-actin proteins were then studied using ICC and flow cytometry assays. Also, the expression of VSMC specific markers such as smooth muscle myosin heavy chain (SMMHC) and smooth muscle alpha-actin (α-SMA) were evaluated using RT-PCR test. In the final phase of this study, the sheep decellularized vessel was employed as a scaffold for seeding these cells. Based on the results, electrical stimulation resulted in some morphological alterations in VSMCs. Furthermore, the observed reductions in the expression levels of vimentin, nestin and ß-actin proteins and increase in the expression of SMMHC and α-SMA markers showed that it is possible to convert the synthetic phenotype to the contractile one using the studied regime of electrical stimulation. Finally, it can be concluded that electrical stimulation can significantly affect the phenotype of VSMCs, as demonstrated in this study.


Assuntos
Actinas , Músculo Liso Vascular , Animais , Ovinos , Músculo Liso Vascular/metabolismo , Actinas/metabolismo , Nestina , Vimentina/metabolismo , Diferenciação Celular/fisiologia , Fenótipo , Estimulação Elétrica , Células Cultivadas , Proliferação de Células
15.
J Neurointerv Surg ; 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37500477

RESUMO

BACKGROUND: Vasospasm and delayed cerebral ischemia (DCI) are the leading causes of morbidity and mortality after intracranial aneurysmal subarachnoid hemorrhage (aSAH). Vasospasm detection, prevention and management, especially endovascular management varies from center to center and lacks standardization. We aimed to evaluate this variability via an international survey of how neurointerventionalists approach vasospasm diagnosis and endovascular management. METHODS: We designed an anonymous online survey with 100 questions to evaluate practice patterns between December 2021 and September 2022. We contacted endovascular neurosurgeons, neuroradiologists and neurologists via email and via two professional societies - the Society of NeuroInterventional Surgery (SNIS) and the European Society of Minimally Invasive Neurological Therapy (ESMINT). We recorded the physicians' responses to the survey questions. RESULTS: A total of 201 physicians (25% [50/201] USA and 75% non-USA) completed the survey over 10 months, 42% had >7 years of experience, 92% were male, median age was 40 (IQR 35-46). Both high-volume and low-volume centers were represented. Daily transcranial Doppler was the most common screening method (75%) for vasospasm. In cases of symptomatic vasospasm despite optimal medical management, endovascular treatment was directly considered by 58% of physicians. The most common reason to initiate endovascular treatment was clinical deficits associated with proven vasospasm/DCI in 89%. The choice of endovascular treatment and its efficacy was highly variable. Nimodipine was the most common first-line intra-arterial therapy (40%). Mechanical angioplasty was considered the most effective endovascular treatment by 65% of neurointerventionalists. CONCLUSION: Our study highlights the considerable heterogeneity among the neurointerventional community regarding vasospasm diagnosis and endovascular management. Randomized trials and guidelines are needed to improve standard of care, determine optimal management approaches and track outcomes.

16.
Neuropathology ; 32(3): 306-10, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22017366

RESUMO

Chondromas are unusual tumors that arise from the base of the skull and have a predilection for the spheno-ethmoidal region. Chondromas represent less than 0.5% of all intracranial tumors. In rare instances, these tumors originate from the dura mater of the convexity. Fewer than 30 cases of dural chondromas arising from the convexity or the falx are reported in the literature. In this study, we describe a new case of convexity chondroma. We discuss the radiological and histological features of this case and also review the literature.


Assuntos
Condroma/patologia , Dura-Máter/patologia , Neoplasias da Base do Crânio/patologia , Angiografia Cerebral , Condroma/cirurgia , Diagnóstico Diferencial , Feminino , Cefaleia/etiologia , Humanos , Imuno-Histoquímica , Antígeno Ki-67/metabolismo , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Cervicalgia/etiologia , Procedimentos Neurocirúrgicos , Proteínas S100/metabolismo , Neoplasias da Base do Crânio/cirurgia , Tomografia Computadorizada por Raios X , Adulto Jovem
17.
Cureus ; 14(3): e22905, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35399411

RESUMO

Posteriorly migrated disc extrusion may mimic tumoral masses on MRI with contrast; still, this diagnosis must be evoked in patients presenting acute low back pain with a posterior epidural mass. We describe a case of epidural posterior migration of an inflammatory lumbar disc herniation in a young patient with acute lumbosciatica. MRI showed an intracanalar mass with intense global enhancement, which is an uncommon feature of this rare condition.

18.
Iran J Pathol ; 17(2): 174-182, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35463727

RESUMO

Background & Objective: Cell surface expression of sortilin in different types of cancer signifies it as a therapeutic target for cancer therapy. The aim of this study was to detect sortilin expression in bladder cancer cells using an anti-sortilin monoclonal antibody (mAb) to evaluate sortilin as a target for developing diagnostic and therapeutic agents against bladder carcinoma. Methods: The protein expression of sortilin in bladder cancer tissues and cell lines (5637 and EJ138) was investigated by immunohistochemistry (IHC), immune-cytochemistry (ICC), and flow cytometry. Furthermore, the capability of anti-sortilin mAb in apoptosis induction in bladder cancer cells was evaluated. Results: A high expression level was observed in bladder carcinoma tissues (P≤0.001) and cell lines, using IHC and ICC, respectively. Flow cytometry results showed cell surface expression of 27.5±3% (P≤0.01), 74.4±7.8% (P≤0.001), and 4.2±0.4% of sortilin in EJ138, 5637, and HFFF cells, respectively. In EJ138 anti-sortilin mAb induced apoptosis in 25.2±11.5% (P≤0.05) (early) and 4.5±1.1% (P>0.05) (late) after 6 h incubation, while for 12 h, the values of 11.6±3.8% (P>0.05) and 20.7±4.4% (P≤0.05) were achieved. In 5637 cells, 6 h incubation resulted in 10.2±0.3% (P>0.05) and 6.6±1.4% (P>0.05) apoptosis induction, while these values were 12.1±0.8% (P>0.05) and 27.4±4.5% (P≤0.01) after 12 h. The HFFF cells did not show significant apoptosis. Conclusion: The overexpression of sortilin in bladder tumor cells and its potential in inducing apoptosis via directed targeting with the specific monoclonal antibody may represent this protein as a potential candidate of targeted therapy in bladder carcinoma.

19.
Bioelectrochemistry ; 147: 108161, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35659688

RESUMO

Coronavirus disease (COVID-19) is a new and highly contagious disease posing a threat to global public health and wreaking havoc around the world. It's caused by the Coronavirus that causes severe acute respiratory syndrome (SARS-CoV-2). In the current pandemic situation, rapid and accurate SARS-CoV-2 diagnosis on a large scale is critical for early-stage diagnosis. Early detection and monitoring of viral infections can aid in controlling and preventing infection in large groups of people. Accordingly, we developed a sensitive and high-throughput sandwich electrochemiluminescence immunosensor based on antigen detection for COVID-19 diagnosis (the spike protein of SARS-CoV-2). For the spike protein of SARS-CoV-2, the ECL biosensor had a linear range of 10 ng mL-1 to 10 µg mL-1 with a limit of detection of 1.93 ng mL-1. The sandwich ECL immunosensor could be used in early clinical diagnosis due to its excellent recovery in detecting SARS-CoV-2, rapid analysis (90 min), and ease of use.


Assuntos
Técnicas Biossensoriais , COVID-19 , Nanocompostos , COVID-19/diagnóstico , Teste para COVID-19 , Técnicas Eletroquímicas , Humanos , Imunoensaio , Luminol , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus
20.
Avicenna J Med Biotechnol ; 14(1): 37-45, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35509360

RESUMO

Background: Sortilin has an important role in various malignances and can be used as a promising target to eradicate cancer cells. Methods: In this study, the expression of sortilin in 4T1 and MDA-MB231 cell lines was evaluated by flow cytometry and immunocytochemistry. Apoptosis assay was also applied to evaluate apoptosis induction in 4T1 and MDA-MB231 cell lines. Results: Based on cell surface flow cytometry results, anti-sortilin (2D8-E3) mAb could recognize sortilin molecules in 79.2% and 90.3% of 4T1 and MDA-MB231 cell-lines, respectively. The immunocytochemistry staining results confirmed sortilin surface expression. Apoptosis assay indicated that anti-sortilin mAb could induce apoptosis in 4T1 and MDA-MB231 cell lines. Conclusion: Our study revealed the important role of surface sortilin in breast carcinoma cell survival and its possible application as a therapeutic agent in cancer targeted therapies.

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