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1.
Front Bioeng Biotechnol ; 10: 1036224, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36406228

RESUMO

Screen-printed electrodes (SPEs) are promising candidates for fabricating biosensing platforms in the laboratory and industry due to the various advantages they involve. The primary method for fabricating SPEs is 2D printing. However, commercial SPEs have some limitations due to the specific ports and connections they require, inflexible design, high prices, and decreased efficiency after a short time. This article introduces high performance, feasible, and cost-effective gold SPEs based on the combination of printed circuit board substrate (PCBs) and sputtering methods for electrochemical biosensing platforms. First, we discuss a general gold SPE development procedure that helps researchers to develop specific designs. The final developed version of SPEs was characterized in the second step, showing positive performance in electrochemical parameters because of the optimization of design and fabrication steps. In the study's final phase, SPEs were used to fabricate a simple platform for breast cancer cell detection as a proof of concept without using any linker or labeling step. The designed immunosensor is very simple and cost-effective, showing a linear calibration curve in the range of 10 - 2× 102 cells mL-1 (R 2 = 0.985, S/N = 3). This research can be used as a reference for future studies in SPEs-based biosensors because of the flexibility of its design and the accessibility of the manufacturing equipment required.

2.
PLoS One ; 17(6): e0267608, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35727837

RESUMO

Identifying individuals with early mild cognitive impairment (EMCI) can be an effective strategy for early diagnosis and delay the progression of Alzheimer's disease (AD). Many approaches have been devised to discriminate those with EMCI from healthy control (HC) individuals. Selection of the most effective parameters has been one of the challenging aspects of these approaches. In this study we suggest an optimization method based on five evolutionary algorithms that can be used in optimization of neuroimaging data with a large number of parameters. Resting-state functional magnetic resonance imaging (rs-fMRI) measures, which measure functional connectivity, have been shown to be useful in prediction of cognitive decline. Analysis of functional connectivity data using graph measures is a common practice that results in a great number of parameters. Using graph measures we calculated 1155 parameters from the functional connectivity data of HC (n = 72) and EMCI (n = 68) extracted from the publicly available database of the Alzheimer's disease neuroimaging initiative database (ADNI). These parameters were fed into the evolutionary algorithms to select a subset of parameters for classification of the data into two categories of EMCI and HC using a two-layer artificial neural network. All algorithms achieved classification accuracy of 94.55%, which is extremely high considering single-modality input and low number of data participants. These results highlight potential application of rs-fMRI and efficiency of such optimization methods in classification of images into HC and EMCI. This is of particular importance considering that MRI images of EMCI individuals cannot be easily identified by experts.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos
3.
J Clin Neurosci ; 99: 99-108, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35278936

RESUMO

BACKGROUND: Automated segmentation methods are developed to help with the segmentation of different brain areas. However, their reliability has yet to be fully investigated. To have a more comprehensive understanding of the distribution of changes in Alzheimer's disease (AD), as well as investigating the reliability of different segmentation methods, in this study we compared volumes of cortical and subcortical brain segments, using HIPS, volBrain, CAT and BrainSuite automated segmentation methods between AD, mild cognitive impairment (MCI) and healthy controls (HC). METHODS: A total of 182 MRI images were taken from the minimal interval resonance imaging in Alzheimer's disease (MIRIAD; 22 AD and 22 HC) and the Alzheimer's disease neuroimaging initiative database (ADNI; 43 AD, 50 MCI and 45 HC) datasets. Statistical methods were used to compare different groups as well as the correlation between different methods. RESULTS: The two methods of volBrain and CAT showed a strong correlation (p's < 0.035 Bonferroni corrected for multiple comparisons). The two methods, however, showed no significant correlation with BrainSuite (p's > 0.820 Bonferroni corrected). Furthermore, BrainSuite did not follow the same trend as the other three methods and only HIPS, volBrain and CAT showed strong conformity with the past literature with strong correlation with mini mental state examination (MMSE) scores. CONCLUSION: Our results showed that automated segmentation methods HIPS, volBrain and CAT can be used in the classification of HC, AD and MCI. This is an indication that such methods can be used to inform researchers and clinicians of underlying mechanisms and progression of AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Progressão da Doença , Humanos , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Reprodutibilidade dos Testes
4.
Sci Rep ; 12(1): 1020, 2022 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-35046444

RESUMO

Alzheimer's disease (AD) is the most prevalent form of dementia. The accurate diagnosis of AD, especially in the early phases is very important for timely intervention. It has been suggested that brain atrophy, as measured with structural magnetic resonance imaging (sMRI), can be an efficacy marker of neurodegeneration. While classification methods have been successful in diagnosis of AD, the performance of such methods have been very poor in diagnosis of those in early stages of mild cognitive impairment (EMCI). Therefore, in this study we investigated whether optimisation based on evolutionary algorithms (EA) can be an effective tool in diagnosis of EMCI as compared to cognitively normal participants (CNs). Structural MRI data for patients with EMCI (n = 54) and CN participants (n = 56) was extracted from Alzheimer's disease Neuroimaging Initiative (ADNI). Using three automatic brain segmentation methods, we extracted volumetric parameters as input to the optimisation algorithms. Our method achieved classification accuracy of greater than 93%. This accuracy level is higher than the previously suggested methods of classification of CN and EMCI using a single- or multiple modalities of imaging data. Our results show that with an effective optimisation method, a single modality of biomarkers can be enough to achieve a high classification accuracy.


Assuntos
Encéfalo/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuroimagem/métodos
5.
Sci Rep ; 11(1): 20657, 2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34667242

RESUMO

In this paper, various multi-layer shields are designed, optimized, and analyzed for electron and proton space environments. The design process is performed for various suitable materials for the local protection of sensitive electronic devices using MCNPX code and the Genetic optimization Algorithm. In the optimizations process, the total ionizing dose is 53.3% and 72% greater than the aluminum shield for proton and electron environments, respectively. Considering the importance of the protons in the LEO orbits, the construction of the shield was based on designing a proton source. A sample shield is built using a combination of Aluminum Bronze and molybdenum layers with a copper carrier to demonstrate the idea. Comparisons of radiation attenuation coefficient results indicate a good agreement between the experimental, simulation, and analytical calculations results. The good specifications of the proposed multi-layer shield prove their capability and ability to use in satellite missions for electronic device protection.

6.
J Neurosurg Case Lessons ; 2(18): CASE21170, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36061624

RESUMO

BACKGROUND: Central nervous system (CNS) tuberculomas are a feared complication of tuberculosis (TB) infection. These lesions can present in varying manners and are associated with significant morbidity and mortality. Prompt diagnosis and treatment of the lesion and the underlying infection are critical in the care of these patients. The authors presented a case of a 45-year-old Yemeni immigrant presenting with a 3-month history of severe right temporo-occipital headaches with photophobia and night sweats. Imaging showed a rim-enhancing lesion in the right cerebellar hemisphere. OBSERVATIONS: Laboratory tests were unremarkable and within normal limits. QuantiFERON testing was negative, ruling out latent TB infection. The patient received a suboccipital craniotomy, and resection of the cerebellar lesion showed caseating granuloma formation, which was positive for acid-fast bacilli and Fite stain. LESSONS: CNS tuberculomas are an important differential to consider in patients with a history of primary TB, regardless of active disease or immunocompetent status. Resection of these lesions remains a viable treatment option that is safe and effective.

7.
J Periodontol ; 92(4): 580-591, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32846000

RESUMO

BACKGROUND: Peri-implantitis treatments are mainly based on protocols for teeth but have not shown favorable outcomes for implants. The potential role of titanium dissolution products in peri-implantitis necessitate the consideration of material properties in devising treatment protocols. We assessed implant cleaning interventions on (1) bacterial removal from Ti-bound biofilms, (2) Ti surface alterations and related Ti particle dissolution, and (3) cytocompatibility. METHODS: Acid-etched Ti discs were inoculated with human peri-implant plaque biofilms and mechanical antimicrobial interventions were applied on the Ti-bound biofilms for 30 seconds each: (1) rotary nylon brush; (2) Ti brush; (3) water-jet on high and (4) low, and compared to sterile, untreated and Chlorhexidine-treated controls. We assessed colony forming units (CFU) counts, biofilm removal, surface changes via scanning electron microscopy (SEM) and atomic force microscopy (AFM), and Ti dissolution via light microscopy and Inductively-coupled Mass Spectrometry (ICP-MS). Biological effects of Ti particles and surfaces changes were assessed using NIH/3T3 fibroblasts and MG-63 osteoblastic cell lines, respectively. RESULTS: Sequencing revealed that the human biofilm model supported a diverse biofilm including known peri-implant pathogens. WJ and Nylon brush were most effective in reducing CFU counts (P < 0.01 versus control), whereas Chlorhexidine was least effective; biofilm imaging results were confirmatory. Ti brushes led to visible streaks on the treated surfaces, reduced corrosion resistance and increased Ti dissolution over 30 days of material aging as compared to controls, which increase was amplified in the presence of bacteria (all P-val < 0.05). Ti particles exerted cytotoxic effects against fibroblasts, whereas surfaces altered by Ti brushes exhibited reduced osteoconductivity versus controls (P < 0.05). CONCLUSIONS: Present findings support that mechanical treatment strategies selected for implant biofilm removal may lead to Ti dissolution. Ti dissolution should become an important consideration in the clinical selection of peri-implantitis treatments and a necessary criterion for the regulatory approval of instruments for implant hygiene.


Assuntos
Implantes Dentários , Peri-Implantite , Biofilmes , Materiais Dentários , Humanos , Peri-Implantite/prevenção & controle , Solubilidade , Propriedades de Superfície , Titânio
8.
Methods Mol Biol ; 2125: 57-72, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31848892

RESUMO

Magnetic nanoparticles have demonstrated considerable capacity for theranosis purposes due to their unique characteristics, including magnetic properties, comparable size to biomolecules, favorable conjugations of drugs and biomolecules, ability to labeling, and capability of sensing, separation, detection, and targeted drug delivery. They could be exploited in magnetic resonance imaging as the contrast agents and also warmed as exposed to an external magnetic AC field that could be applied in hyperthermia. Here, progresses and advances in the strategy and assembly of fluorescent magnetic nanoparticles are presented for stem cell tracing and drugs/biomolecules targeting into cells.


Assuntos
Diagnóstico por Imagem/métodos , Hipertermia Induzida , Nanopartículas de Magnetita/química , Células-Tronco Mesenquimais/citologia , Coloração e Rotulagem , Animais , Compostos de Cádmio/química , Diferenciação Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Células Cultivadas , Fluorescência , Humanos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Pontos Quânticos/química , Receptores de Quimiocinas/metabolismo , Dióxido de Silício/química , Telúrio/química
9.
Micromachines (Basel) ; 9(10)2018 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-30424443

RESUMO

Deep brain stimulation (DBS) is a successful medical therapy for many treatment resistant neuropsychiatric disorders such as movement disorders; e.g., Parkinson's disease, Tremor, and dystonia. Moreover, DBS is becoming more and more appealing for a rapidly growing number of patients with other neuropsychiatric diseases such as depression and obsessive compulsive disorder. In spite of the promising outcomes, the current clinical hardware used in DBS does not match the technological standards of other medical applications and as a result could possibly lead to side effects such as high energy consumption and others. By implementing more advanced DBS devices, in fact, many of these limitations could be overcome. For example, a higher channels count and smaller electrode sites could allow more focal and tailored stimulation. In addition, new materials, like carbon for example, could be incorporated into the probes to enable adaptive stimulation protocols by biosensing neurotransmitters in the brain. Updating the current clinical DBS technology adequately requires combining the most recent technological advances in the field of neural engineering. Here, a novel hybrid multimodal DBS probe with glassy carbon microelectrodes on a polyimide thin-film device assembled on a silicon rubber tubing is introduced. The glassy carbon interface enables neurotransmitter detection using fast scan cyclic voltammetry and electrophysiological recordings while simultaneously performing electrical stimulation. Additionally, the presented DBS technology shows no imaging artefacts in magnetic resonance imaging. Thus, we present a promising new tool that might lead to a better fundamental understanding of the underlying mechanism of DBS while simultaneously paving our way towards better treatments.

10.
J Cardiovasc Thorac Res ; 10(4): 227-230, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30680082

RESUMO

Introduction: Coronary Artery Disease (CAD) is known as the major cause of morbidity and mortality in the world with a growing trend, especially in some developing countries. CAD commonly observed in elderly cases, however; recently it is usually found in young adults. In this study, we aimed to evaluate the prevalence of anti-phospholipid antibody syndrome (APS) in patients with premature CAD. Methods: The cross-sectional study was conducted in Baqiyatallah hospital from April 2012 to April 2016. Patients with premature CAD were included in the study. The data regarding the laboratory tests, echocardiography, and angiography were obtained from all cases. Results: Overall 133 eligible patients were included in the study. In the first set of the laboratory test, 18 patients were recognized to have APS (13.53%). The second confirmatory APA test was showing 3 of 18 patients were considered to have APS (2.25%). Conclusion: The results showed there is an association between the risk of developing Premature CAD and APS could potentially. The APS may have significant effects on the risk of coronary heart disease, especially in young adults.

11.
Life Sci ; 146: 52-7, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26764231

RESUMO

AIMS: Previous reports on the possible effects of Extremely Low Frequency Magnetic Fields (ELF MF) on mood have been paradoxical in different settings while no study has yet been conducted on animal behavior. In addition, it was shown that ELF MF exposure makes an increase in brain nitric oxide level. Therefore, in the current study, we aimed to assess the possible effect(s) of ELF MF exposure on mice Forced Swimming Test (FST) and evaluate the probable role of the increased level of nitric oxide in the observed behavior. MAIN METHODS: Male adult mice NMRI were recruited to investigate the short term and long term ELF MF exposure (0.5 mT and 50 Hz, single 2h and 2 weeks 2h a day). Locomotor behavior was assessed by using open-field test (OFT) followed by FST to evaluate the immobility time. Accordingly, NΩ-nitro-l-arginine methyl ester 30 mg/kg was used to exert anti-depressant like effect. KEY FINDINGS: According to the results, short term exposure did not alter the immobility time, whereas long term exposure significantly reduces immobility time (p<0.01). However, it was revealed that the locomotion did not differ among all experimental groups. Short term exposure reversed the anti-depressant like effect resulting from 30 mg/kg of NΩ-nitro-l-arginine methyl ester (p<0.01). SIGNIFICANCE: It has been concluded that long term exposure could alter the depressive disorder in mice, whereas short term exposure has no significant effect. Also, reversing the anti-depressant activity of L-NAME indicates a probable increase in the brain nitric oxide.


Assuntos
Transtorno Depressivo/etiologia , Campos Magnéticos/efeitos adversos , Óxido Nítrico/efeitos da radiação , Transdução de Sinais/efeitos da radiação , Animais , Antidepressivos/farmacologia , Comportamento Animal/efeitos da radiação , Transtorno Depressivo/metabolismo , Inibidores Enzimáticos/farmacologia , Masculino , Camundongos , Atividade Motora/efeitos da radiação , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/antagonistas & inibidores , Natação/psicologia
12.
Spine J ; 13(12): e1-5, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24051332

RESUMO

BACKGROUND CONTEXT: Brown-Séquard syndrome is characterized by a hemisection of the spinal cord most commonly after spinal trauma or neoplastic disease. The injury causes ipsilateral hemiplegia and proprioceptive sensory disturbances with contralateral loss of pain and temperature sensation. Patients with Brown-Séquard syndrome have the best prognosis of all spinal cord injury patterns. At this time, the ideal management for Brown-Séquard syndrome after penetrating trauma has yet to be defined. PURPOSE: To report a case of a gun shot wound to the upper cervical spine that resulted in Brown-Séquard syndrome and was treated effectively with early cervical spine decompression and fusion. STUDY DESIGN: Observational case report. METHODS: A 28-year-old woman presented after sustaining a low-velocity gun shot wound in to the upper cervical spine in a civilian assault. On initial presentation, she had 0/5 motor scores in the left upper and lower extremities and normal motor scores on the right. Sensory examination was limited as she was intubated and sedated on admission due to airway compromise. A computed tomography scan revealed a bullet lodged in the vertebral body of C3 with boney fragments and soft tissue encroaching on the spinal cord. Subsequently, she underwent C3 corpectomy, bulletectomy, and anterior cervical decompression with fusion. RESULTS: Intraoperatively, no dural disruption or cerebral spinal fluid leak was noted, and her posterior longitudinal ligament was intact. One month postoperatively, her left lower extremity motor score was 5/5 with movement of her left thumb and all fingers. Strength in her biceps, triceps, and wrist extensors and flexors was 3/5. Her functional capacity and strength gradually improved. CONCLUSIONS: Reinke et al. support surgical intervention for patients with incomplete paraplegia after the patient is medically stabilized, although their case report discussed lower thoracic injury, which carries a more favorable prognosis. All other prior case reports and prospective studies that reported favorable outcomes after Brown-Séquard syndrome involved the midthoracic, low thoracic, or lumbar spinal levels. This report is the first case of Brown-Séquard syndrome after a high cervical gun shot wound, which was managed with immediate decompression and fusion, where near complete recovery was obtained.


Assuntos
Síndrome de Brown-Séquard/etiologia , Síndrome de Brown-Séquard/cirurgia , Traumatismos da Medula Espinal/etiologia , Traumatismos da Medula Espinal/cirurgia , Ferimentos por Arma de Fogo/complicações , Adulto , Síndrome de Brown-Séquard/diagnóstico por imagem , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/lesões , Vértebras Cervicais/cirurgia , Descompressão Cirúrgica , Feminino , Humanos , Radiografia , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/diagnóstico por imagem , Fusão Vertebral , Ferimentos por Arma de Fogo/diagnóstico por imagem , Ferimentos por Arma de Fogo/cirurgia
13.
Artigo em Inglês | MEDLINE | ID: mdl-23230472

RESUMO

BACKGROUND AND AIMS: The use of fluoride mouthrinses has been proved to be one of the most effective ways to prevent tooth decay. A community based program using F+ rinse at school has also proved to be well-controlled and efficient. The aim of this investigation was to evaluate fluoride uptake level of a locally prepared NaF rinse used in Iran's school program during 2005. MATERIALS AND METHODS: A total of 30 freshly extracted sound human premolars were collected and divided into two groups of 15. Each tooth then underwent two steps of sectioning; first the root was amputated from CEJ and then a longitudi-nal section was performed in bucco-lingual direction to provide two similar samples of the same tooth. A specific hemi-circular area on either of the experimental halves was treated by NaF rinse from USA or a locally prepared NaF used in school programs. Two subsequent biopsies were taken from each half using acid etch enamel biopsy technique. Fluoride and calcium content of the specimens were measured in order to evaluate fluoride uptake level and biopsy depth effect, respectively. Col-lected data were recorded in the forms provided and statistical analysis, mostly descriptive, was performed for comparison. RESULTS: Based on the data collected, it appears that the use of F+ rinse would clearly improve enamel quality by a rise in fluoride concentration. Statistical analysis using a paired t-test and repeated measure method revealed that with 95% confi-dence fluoride concentration increases at both levels of biopsy with no statistically significant differences between the samples treated with two rinses. CONCLUSION: There seem to be reasonable potential for the clinical use of Iranian brand fluoride mouthrinse. There was no significant difference between the level of uptake from NaF from USA and the Iranian product in 2 layers of enamel biopsy.

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