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1.
Tissue Cell ; 87: 102338, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38428370

RESUMO

Hair loss disorder (alopecia) affects numerous people around the world. The low effectiveness and numerous side effects of common treatments have prompted researchers to investigate alternative and effective solutions. Hair follicle (HF) bioengineering is the knowledge of using hair-inductive (trichogenic) cells. Most bioengineering-based approaches focus on regenerating folliculogenesis through manipulation of regulators of physical/molecular properties in the HF niche. Despite the high potential of cell therapy, no cell product has been produced for effective treatment in the field of hair regeneration. This problem shows the challenges in the functionality of cultured human hair cells. To achieve this goal, research and development of new and practical approaches, technologies and biomaterials are needed. Based on recent advances in the field, this review evaluates emerging HF bioengineering strategies and the future prospects for the field of tissue engineering and successful HF regeneration.


Assuntos
Folículo Piloso , Engenharia Tecidual , Humanos , Bioengenharia , Materiais Biocompatíveis
2.
Cureus ; 16(3): e55511, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38440202

RESUMO

Hospitals across the United States use patient satisfaction surveys to assess the quality of inpatient and outpatient services provided to patients when they interact with the healthcare system. Results from this survey are used as input to identify weaknesses in the system with the intention of providing appropriate intervention. Here, we report the results of the quality improvement project completed in an acute healthcare facility. Patient satisfaction was evaluated based on indices established by the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS). Responses from 400 patients admitted into the hospital between July 2022 and June 2023 were obtained using a pre-designed questionnaire prepared by HCAHPS on behalf of Prime Healthcare Services. Indices of assessment include doctor-patient interaction, nurse-patient interaction, hospital responsiveness to patient needs, hospital environment, communication about medicine, discharge information, transition of care, overall assessment, and willingness to recommend. The best hospital performance was seen in the dissemination of discharge information, while the worst performance was noted in the transition of care and communication about medicine. Appropriate recommendations were made to improve on these weak areas.

3.
Water Environ Res ; 96(1): e10960, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38168046

RESUMO

As an emerging desalination technology, forward osmosis (FO) can potentially become a reliable method to help remedy the current water crisis. Introducing uncomplicated and precise models could help FO systems' optimization. This paper presents the prediction and evaluation of FO systems' membrane flux using various artificial intelligence-based models. Detailed data gathering and cleaning were emphasized because appropriate modeling requires precise inputs. Accumulating data from the original sources, followed by duplicate removal, outlier detection, and feature selection, paved the way to begin modeling. Six models were executed for the prediction task, among which two are tree-based models, two are deep learning models, and two are miscellaneous models. The calculated coefficient of determination (R2 ) of our best model (XGBoost) was 0.992. In conclusion, tree-based models (XGBoost and CatBoost) show more accurate performance than neural networks. Furthermore, in the sensitivity analysis, feed solution (FS) and draw solution (DS) concentrations showed a strong correlation with membrane flux. PRACTITIONER POINTS: The FO membrane flux was predicted using a variety of machine-learning models. Thorough data preprocessing was executed. The XGBoost model showed the best performance, with an R2 of 0.992. Tree-based models outperformed neural networks and other models.


Assuntos
Inteligência Artificial , Purificação da Água , Purificação da Água/métodos , Membranas Artificiais , Osmose , Água
4.
Arch Oral Biol ; 159: 105878, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38171058

RESUMO

OBJECTIVE: We investigated the effects of molar tooth shortening on the mRNA expression of the AßPP/BACE1, BDNF/TrkB, and Bax/Bcl-2 signaling pathways in the Wistar male rat hippocampal regions. DESIGN: Four groups (n = 5 per group) of male Wistar rats (control, SRM (shortened right molar), SLM (shortened left molar), and SBM (shortened bilateral molar)) were used. RNA was isolated from the hippocampus and transformed into cDNA. Real-time quantitative PCR was used to evaluate the mRNA expression levels of AßPP, BACE1, Bax, Bcl-2, BDNF, and TrkB. RESULTS: Differential mRNA expression was observed in rat groups. SBM significantly upregulated the AßPP, BACE1, and Bax mRNA expressions, whereas the expression levels of Bcl-2, BDNF, and TrkB were decreased. SRM and SLM approximately had the same effect on the expression enhancement of AßPP, BACE1, and Bax; however, SRM was more effective than SLM in increasing the expression of these genes. CONCLUSIONS: Symmetrical molar teeth shortening affected the mRNA expression of AßPP and BACE1, which is related to learning and memory dysfunction.


Assuntos
Secretases da Proteína Precursora do Amiloide , Fator Neurotrófico Derivado do Encéfalo , Ratos , Masculino , Animais , Ratos Wistar , Secretases da Proteína Precursora do Amiloide/metabolismo , Proteína X Associada a bcl-2/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Hipocampo/metabolismo , RNA Mensageiro/metabolismo
5.
Brain Res ; 1825: 148688, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38042394

RESUMO

Neurodegenerative diseases arise due to slow and gradual loss of structure and/or function of neurons and glial cells and cause different degrees of loss of cognition abilities and sensation. The little success in developing effective treatments imposes a high and regressive economic impact on society, patients and their families. In recent years, regenerative medicine has provided a great opportunity to research new innovative strategies with strong potential to treatleva these diseases. These effects are due to the ability of suitable cells and biomaterials to regenerate damaged nerves with differentiated cells, creating an appropriate environment for recovering or preserving existing healthy neurons and glial cells from destruction and damage. Ultimately, a better understanding and thus a further investigation of stem cell technology, tissue engineering, gene therapy, and exosomes allows progress towards practical and effective treatments for neurodegenerative diseases. Therefore, in this review, advances currently being developed in regenerative medicine using animal models and human clinical trials in neurological disorders are summarized.


Assuntos
Doenças Neurodegenerativas , Medicina Regenerativa , Animais , Humanos , Doenças Neurodegenerativas/terapia , Engenharia Tecidual , Células-Tronco , Neurônios
6.
Gait Posture ; 108: 28-34, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37979323

RESUMO

BACKGROUND: Although the effects of footwear type on joint stiffness have previously been investigated, researchers did not consider foot flexibility. Thus, the present investigation aimed to determine the interaction effects of footwear type, static navicular drop and dynamic ankle pronation on dynamic joint stiffness in running. RESEARCH QUESTION: Does the footwear types in interaction with the foot posture affect the stiffness of the joints of the lower limb? METHODS: Forty-seven male individuals participated in this study. Firstly, they were divided into the high navicular, low navicular, and normal navicular drop. Secondly, they were divided into the high dynamic ankle pronation, low dynamic ankle pronation, and normal dynamic ankle pronation groups. Participants performed three running trials at 3 ± 0.2 m/s at minimalist footwear, conventional footwear, and barefoot conditions. We collected the ground reaction forces and three-dimensional kinematic data and calculated joint stiffness over the stance phase. RESULTS: There was no significant main effect of navicular drop or dynamic ankle pronation on dynamic joint stiffness for the ankle, knee, and hip (p > 0.05). However, footwear type significantly affected dynamic joint stiffness. The pairwise comparison revealed that the ankle and hip dynamic joint stiffness magnitudes in the conventional footwear condition were greater than in the barefoot and minimalist footwear conditions (p 0.001). In contrast, the knee dynamic joint stiffness magnitude in the conventional footwear condition was lesser than in barefoot and minimalist footwear conditions (p 0.001). SIGNIFICANCE: The navicular drop or dynamic ankle pronation did not influence lower limb joint stiffness, and there was no significant interaction between navicular drop or dynamic ankle pronation and footwear on lower limb dynamic joint stiffness. However, conventional footwear increased the ankle and hip dynamic joint stiffness while reducing knee dynamic joint stiffness, leading to changes in transfer energy, which could have implications for relative injury risk.


Assuntos
Tornozelo , Corrida , Masculino , Humanos , Pronação , Sapatos , Extremidade Inferior , Articulação do Tornozelo , Corrida/lesões , Fenômenos Biomecânicos
7.
Biotechnol J ; 19(1): e2300462, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38073122

RESUMO

New formulations of Amphotericin-B (Am-B), the most popular therapeutic drug for many human infections such as parasitic and fungal pathogens, are safe, economical, and effective in the world. Several newly designed carrier systems for Am-B can also be considered orally with sufficient gastrointestinal permeability and good solubility. However, the clinical application of several new formulations of Am-B with organ cytotoxicity, low bioavailability, high costs, and technical problems have caused some issues. Therefore, more attention and scientific design are required to progress safe and effective drug delivery systems. Currently, the application of nano-based technology and nanomaterials in the advancement of drug delivery systems exhibits promising outcomes to cure many human systemic infections. Designing novel drug delivery systems including solid lipid nanostructured materials, lipo-polymersomes, drug conjugates and microneedles, liposomes, polymer and protein-based nanostructured materials, dendrimers, emulsions, mixed micelles, polymeric micelles, cyclodextrins, nanocapsules, and nanocochleate for Am-B has many advantages to reducing several related issues. The unique properties of nanostructured particles such as proper morphology, small size, surface coatings, and, electrical charge, permit scientists to design new nanocomposite materials against microorganisms for application in various human diseases. These features have made these nanoparticles an ideal candidate for drug delivery systems in clinical approaches to cure a number of human disorders and currently, several therapeutic nanostructured material formulations are under different stages of clinical tests. Hence, this scientific paper mainly discussed the advances in new formulations of Am-B for the treatment of human systemic infections and related clinical tests.


Assuntos
Leishmaniose , Micoses , Nanopartículas , Humanos , Anfotericina B/uso terapêutico , Micelas , Sistemas de Liberação de Medicamentos , Micoses/tratamento farmacológico , Leishmaniose/tratamento farmacológico , Polímeros/uso terapêutico
8.
Sci Rep ; 13(1): 21651, 2023 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-38066216

RESUMO

There is limited data on the prevalence of thyroid dysfunction in the older population. This study aimed to determine the prevalence of thyroid dysfunction among a sample of Iranian older adults. A cross-sectional analysis of older adults who aged 60 years and over was conducted. A total of 363 subjects were randomly selected from Birjand longitudinal aging study (BLAS) cohort study. Serum thyroid-stimulating hormone (TSH) level, total thyroxine (T4) and total triiodothyronine (T3) were measured by the enzyme-linked immunosorbent assay (ELISA). Based on thyroid function tests and history of taking medicines used to treat thyroid disorders, participants were classified into the following groups: euthyroid, overt/subclinical hypothyroidism, and overt/subclinical hyperthyroidism. Subsequently, the crude and World Health Organization (WHO) age-standardized prevalence were estimated for different thyroid function categories. A total of 171 men and 192 women, aged 60-94 years, were randomly selected. The crude prevalence of total hypothyroidism was 22.31% (subclinical [18.46%], overt [3.86%]), and that of hyperthyroidism was 1.66% (subclinical [1.38%], overt [0.28%]). The crude prevalence of total thyroid dysfunction was, therefore, 23.97%. A female preponderance was noticed in both total (P-value = 0.035) and overt (P-value = 0.035) hypothyroidism. An increasing trend with age was noticed in the prevalence of total hypothyroidism (P-value = 0.049). Age-standardized prevalence of total hypothyroidism and hyperthyroidism was 26.63% (95% confidence interval [CI] 20.58-33.69%) and 1.11% (95% CI 0.49-2.51%), respectively. A considerable proportion of our study population demonstrated evidence of thyroid dysfunction, particularly subclinical hypothyroidism. Our findings highlight the importance of further investigation of thyroid disorders among older Iranian adults.


Assuntos
Hipertireoidismo , Hipotireoidismo , Doenças da Glândula Tireoide , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Transversais , Irã (Geográfico)/epidemiologia , Estudos de Coortes , Prevalência , Hipotireoidismo/epidemiologia , Hipertireoidismo/epidemiologia , Testes de Função Tireóidea , Tiroxina , Tireotropina
9.
Cancers (Basel) ; 15(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37958402

RESUMO

This study presents a measurement principle for determining the size of the ablation zone in MWA, which could ultimately form an alternative to more expensive monitoring approaches like CT. The measurement method is based on a microwave transmission measurement. A MWA is performed experimentally on ex vivo bovine liver to determine the ablation zone. This setup uses a custom slot applicator performing the MWA at an operating frequency of 2.45 GHz and a custom bowtie antenna measuring the waves transmitted from the applicator. Furthermore, a custom measurement probe is used to determine the dielectric properties. A time-shift analysis is used to determine the radial extent of the ablation zone. Several measurements are carried out with a power of 50 W for 10 min to show the reproducibility. The results show that this method can provide reproducible outcomes to determine the ablation zone with a maximum error of 4.11%.

10.
Tissue Cell ; 85: 102238, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37832248

RESUMO

As a natural material, fish skin contains significant amounts of collagen I and III, and due to its biocompatible nature, it can be used to regenerate various tissues and organs. To use fish skin, it is necessary to perform the decellularization process to avoid the immunological response of the host body. In the process of decellularization, it is crucial to conserve the extracellular matrix (ECM) three-dimensional (3D) structure. However, it is known that decellularization methods may also damage ECM strands arrangement and structure. Moreover, after decellularization, the post-processing of fish skin improves its mechanical and biological properties and preserves its 3D design and strength. Also, sterilization, which is one of the post-processing steps, is mandatory in pre-clinical and clinical settings. In this review paper, the fish skin decellularization methods performed and the various post-processes used to increase the performance of the skin have been studied. Moreover, multiple applications of acellular fish skin (AFS) and its extracted collagen have been reviewed.


Assuntos
Engenharia Tecidual , Tecidos Suporte , Animais , Engenharia Tecidual/métodos , Tecidos Suporte/química , Matriz Extracelular/química , Colágeno , Colágeno Tipo I
11.
Sci Rep ; 13(1): 11966, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37488224

RESUMO

Ionic liquids (ILs) have drawn much attention due to their extensive applications and environment-friendly nature. Refractive index prediction is valuable for ILs quality control and property characterization. This paper aims to predict refractive indices of pure ILs and identify factors influencing refractive index changes. Six chemical structure-based machine learning models called eXtreme Gradient Boosting (XGBoost), Light Gradient Boosting Machine (LightGBM), Categorical Boosting (CatBoost), Convolutional Neural Network (CNN), Adaptive Boosting-Decision Tree (Ada-DT), and Adaptive Boosting-Support Vector Machine (Ada-SVM) were developed to achieve this goal. An enormous dataset containing 6098 data points of 483 different ILs was exploited to train the machine learning models. Each data point's chemical substructures, temperature, and wavelength were considered for the models' inputs. Including wavelength as input is unprecedented among predictions done by machine learning methods. The results show that the best model was CatBoost, followed by XGBoost, LightGBM, Ada-DT, CNN, and Ada-SVM. The R2 and average absolute percent relative error (AAPRE) of the best model were 0.9973 and 0.0545, respectively. Comparing this study's models with the literature shows two advantages regarding the dataset's abundance and prediction accuracy. This study also reveals that the presence of the -F substructure in an ionic liquid has the most influence on its refractive index among all inputs. It was also found that the refractive index of imidazolium-based ILs increases with increasing alkyl chain length. In conclusion, chemical structure-based machine learning methods provide promising insights into predicting the refractive index of ILs in terms of accuracy and comprehensiveness.

12.
J Nutr ; 153(8): 2312-2319, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37356498

RESUMO

BACKGROUND: There is evidence of the role of vitamin D deficiency in cognitive decline. However, the results of studies regarding the relationship between the reduction of vitamin D concentrations and cognitive impairment are heterogeneous. OBJECTIVES: We aimed to answer the question of whether vitamin D deficiency is associated with cognitive decline in older adults. METHODS: In this cross-sectional study, the baseline data of the Birjand Longitudinal Aging Study (BLAS) were analyzed. Of 1420 participants in the BLAS, 1219 participants aged ≥60 y old were included in the present study. Serum concentrations of 25-hydroxyvitamin D [25(OH)D] were measured by the enzyme-linked immunosorbent assay method. The 6-item Cognitive Impairment Test (6-CIT), Mini-Mental State Examination (MMSE), Category Fluency Test (CFT), and Abbreviated Mental Test Score (AMTS) were used to assess cognitive function. Multiple logistic regression analysis, adjusted for potential confounders, was employed to estimate the association between cognitive function and 25(OH)D concentrations. RESULTS: Among study participants, 905 (74.24%) had sufficient vitamin D concentrations (≥20 ng/ml), 209 (17.15%) had insufficient vitamin D concentrations (12-20 ng/ml), and 105 (8.61%) had vitamin D deficiency (<12 ng/ml). There was no significant correlation between serum 25(OH)D concentrations and scores of 6-CIT (P = 0.279), AMTS (P = 0.181), MMSE (P = 0.118), and CFT (P = 0.259). Also, the prevalence of cognitive impairment had no significant relationship with vitamin D status. Finally, in the multiple logistic regression analysis, there was no association between the insufficient or deficient concentrations of 25(OH)D and impaired cognitive function both before and after adjustment for various cofounders. CONCLUSIONS: The present study found no significant association between vitamin D status and cognitive impairment.


Assuntos
Disfunção Cognitiva , Deficiência de Vitamina D , Humanos , Idoso , Irã (Geográfico)/epidemiologia , Estudos Transversais , Vitamina D , Envelhecimento , Vitaminas , Cognição , Disfunção Cognitiva/epidemiologia , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/epidemiologia
13.
J Cell Biochem ; 124(5): 635-655, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37158125

RESUMO

Mitochondrial calcium (Ca2+ ) dynamics play critical roles in regulating vital physiological conditions in the brain. Importantly, Mitochondria-associated endoplasmic reticulum (ER) membranes serve different cellular functions including Ca2+ signaling, bioenergetics, phospholipid biosynthesis, cholesterol esterification, programmed cell death, and communication between the two organelles. Several Ca2+ -transport systems specialize at the mitochondria, ER, and their contact sites that provide tight control of mitochondrial Ca2+ signaling at the molecular level. The biological function of Ca2+ channels and transporters as well as the role of mitochondrial Ca2+ signaling in cellular homeostasis can open new perspectives for investigation and molecular intervention. Emerging evidence suggests that abnormalities in ER/mitochondrial brain functions and dysregulation of Ca2+ homeostasis are neuropathological hallmarks of neurological disorders like Alzheimer's disease, but little evidence is available to demonstrate their relationship to disease pathogenesis and therapeutic approaches. In recent years, the detection of the molecular mechanism regulating cellular Ca2+ homeostasis and also mitochondrial functions have expanded the number of targeted treatments. The main experimental data identify beneficial effects, whereas some scientific trials did not meet the expectations. Together with an overview of the important function of mitochondria, this review paper introduced the possible tested therapeutic approaches that target mitochondria in the context of neurodegenerative diseases. Since these treatments in neurological disorders have shown different degrees of progress, it is essential to perform a detailed assessment of the significance of mitochondrial deterioration in neurodegenerative diseases and of a pharmacological treatment at this stage.


Assuntos
Sinalização do Cálcio , Doenças Neurodegenerativas , Humanos , Cálcio/metabolismo , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Doenças Neurodegenerativas/metabolismo
14.
Int Wound J ; 20(7): 2924-2941, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36924081

RESUMO

Fish skin grafting as a new skin substitute is currently being used in clinical applications. Acceleration of the wound healing, lack of disease transmission, and low cost of the production process can introduce fish skin as a potential alternative to other grafts. An appropriate decellularization process allows the design of 3D acellular scaffolds for skin regeneration without damaging the morphology and extracellular matrix content. Therefore, the role of decellularization processes is very important to maintain the properties of fish skin. In this review article, recent studies on various decellularization processes as well as biological, physical, and mechanical properties of fish skin and its applications with therapeutic effects in wound healing were investigated.


Assuntos
Derme Acelular , Pele Artificial , Animais , Cicatrização , Transplante de Pele , Matriz Extracelular , Peixes
15.
Oral Dis ; 29(3): 1356-1366, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34862999

RESUMO

OBJECTIVE: This study aimed to investigate the relationship between different patterns of molar crown loss and the association between symmetrical and asymmetrical shortening molar teeth with memory impairment. MATERIALS AND METHODS: Male Wistar rats were divided into four groups (n = 10) including control, SLM (shortened left molar), SRM (shortened right molar), and SBM (shortened bilateral molar) groups. Morris water maze (MWM) and passive avoidance test (PAT) were performed to assess spatial and fear memory, respectively. Besides, histological assessment of hippocampus and gingival tissues was done. RESULTS: In the MWM test, SBM and SLM groups had higher escape latency over training trials and spent less time in the target quadrant in the probe trial (p < 0.01). In the PAT, step-through latency was significantly reduced in three groups, and time spent in the dark compartment increased in SBM (p < 0.01) and SLM (p < 0.05) groups. In addition, each teeth shortening group indicated a reduction in density (p < 0.01) and thickness layer (p < 0.05) of pyramidal cells. Gingival was normal after shortening of the molar crown. CONCLUSIONS: Different patterns of molar teeth shortening induced learning and memory impairment; however, symmetrical molar teeth shortening has more effects on memory impairment.


Assuntos
Aprendizagem , Transtornos da Memória , Ratos , Animais , Masculino , Ratos Wistar , Transtornos da Memória/etiologia , Dente Molar
16.
Heliyon ; 8(7): e09817, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35874056

RESUMO

Background and aim: Mental disorders are among the most common diseases in the world. Not only the lack of social support and health services but also the social stigma surrounding individuals with mental disorders and their family members has exacerbated the difficulty of living with and caring for these patients. The present study aimed to determine the effect of group psychological training on the attitudes of family caregivers taking care of patients with schizophrenia as a common mental disorder. Materials and methods: This interventional study was conducted on 60 caregivers of patients with schizophrenia who had a history of hospitalization in the psychiatric ward of Imam Reza Hospital of Birjand in 2020. The intervention group attended eight 90-minute sessions of psychological training in four weeks. However, the control group received no educational intervention during the study period. the opinions about mental illness scale (OMI) modified by Cohen and Struening was used to collect data before and after the intervention. Data were analyzed using SPSS16 by running descriptive statistics, Chi-square, independent t-test, and paired t-test at the significance level of 0.05. Results: The mean scores of attitudes toward mental illness were not significantly different between the intervention (87.37 ± 15.51) and control (89.48 ± 14.08) groups before the intervention (P > 0.05). However, the mean scores of the intervention group (156.44 ± 10.09) increased significantly compared to the mean scores of the control group (88.4 ± 16.15) followed by the intervention (P < 0.05). Conclusion: According to the study results, psychological group training is effective in improving the attitudes of family caregivers of schizophrenic patients. So, it can be applied method of this study as simple, low-cost, and effective in improving the life quality of schizophrenic patients and their families.

17.
J Nanobiotechnology ; 19(1): 327, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34663344

RESUMO

Iron oxide nanoparticles (IONPs) have been proposed as targeted carriers to deliver therapeutic molecules in the central nervous system (CNS). However, IONPs may damage neural tissue via free iron accumulation, protein aggregation, and oxidative stress. Neuroprotective effects of quercetin (QC) have been proven due to its antioxidant and anti-inflammatory properties. However, poor solubility and low bioavailability of QC have also led researchers to make various QC-involved nanoparticles to overcome these limitations. We wondered how high doses or prolonged treatment with quercetin conjugated superparamagnetic iron oxide nanoparticles (QCSPIONs) could improve cognitive dysfunction and promote neurogenesis without any toxicity. It can be explained that the QC inhibits protein aggregation and acts against iron overload via iron-chelating activity, iron homeostasis genes regulation, radical scavenging, and attenuation of Fenton/Haber-Weiss reaction. In this review, first, we present brain iron homeostasis, molecular mechanisms of iron overload that induced neurotoxicity, and the role of iron in dementia-associated diseases. Then by providing evidence of IONPs neurotoxicity, we discuss how QC neutralizes IONPs neurotoxicity, and finally, we make a brief comparison between QC and conventional iron chelators. In this review, we highlight that QC as supplementation and especially in conjugated form reduces iron oxide nanoparticles neurotoxicity in clinical application.


Assuntos
Encéfalo/efeitos dos fármacos , Nanopartículas Magnéticas de Óxido de Ferro/toxicidade , Fármacos Neuroprotetores/farmacologia , Neurotoxinas/toxicidade , Quercetina/farmacologia , Animais , Encéfalo/fisiologia , Modelos Animais de Doenças , Humanos , Ferro/metabolismo , Sobrecarga de Ferro , Camundongos , Doenças Neurodegenerativas , Ratos
18.
Arch Oral Biol ; 127: 105138, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33940515

RESUMO

OBJECTIVE: In the current study, we aimed to investigate the expression profile of TrkA, TrkB, TrkC, and p75NTR neurotrophin receptors because of their roles in the functional differentiation of human exfoliated deciduous teeth (SHED) cells into neural-like cells before and after differentiation of SHED cells into neural-like cells. DESIGN: Total RNAs isolated from dental pulp tissue, SHED cells, and neural-like cells were reverse transcribed into complementary DNA. Neurotrophin receptor expression at mRNA and protein levels were compared in these three cell types by means of real-time PCR and western blot methods. RESULTS: TrkA mRNA increased (713.6 ± 251.5) significantly (p < 0.01) in neural-like cells difference from SHED and TrkB mRNA enhanced to 3618 times in these cells. The expression pattern of TrkC was very similar to the pattern of TrkA, and B. p75NTR mRNA increased 41.99 ± 21.61 fold in neural-like cells and 9.805 ± 4.06 fold in SHED cells. Almost the same pattern was observed for the expression of these receptors at the protein levels. Alterations with different grades and trends in neurotrophin receptors mRNA and protein expression levels were observed in these cells. CONCLUSION: Neurotrophin receptors are important in the existence and differentiation of SHED cells into neuron cells. Therefore, because of the neurogenic potential and accessibility of SHED cells, derived cells from SHED cells can be distinguished as an ideal source for tissue engineering.


Assuntos
Receptor trkA , Receptor trkC , Diferenciação Celular , Expressão Gênica , Humanos , Receptor trkA/genética , Receptor trkC/genética , Receptores de Fator de Crescimento Neural/genética , Dente Decíduo
19.
Nanomaterials (Basel) ; 11(5)2021 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-33922883

RESUMO

Electromechanical sensing devices, based on resins doped with carbon nanotubes, were developed by digital light processing (DLP) 3D printing technology in order to increase design freedom and identify new future and innovative applications. The analysis of electromechanical properties was carried out on specific sensors manufactured by DLP 3D printing technology with complex geometries: a spring, a three-column device and a footstep-sensing platform based on the three-column device. All of them show a great sensitivity of the measured electrical resistance to the applied load and high cyclic reproducibility, demonstrating their versatility and applicability to be implemented in numerous items in our daily lives or in industrial devices. Different types of carbon nanotubes-single-walled, double-walled and multi-walled CNTs (SWCNTs, DWCNTs, MWCNTs)-were used to evaluate the effect of their morphology on electrical and electromechanical performance. SWCNT- and DWCNT-doped nanocomposites presented a higher Tg compared with MWCNT-doped nanocomposites due to a lower UV light shielding effect. This phenomenon also justifies the decrease of nanocomposite Tg with the increase of CNT content in every case. The electromechanical analysis reveals that SWCNT- and DWCNT-doped nanocomposites show a higher electromechanical performance than nanocomposites doped with MWCNTs, with a slight increment of strain sensitivity in tensile conditions, but also a significant strain sensitivity gain at bending conditions.

20.
Materials (Basel) ; 13(15)2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32756526

RESUMO

An immature failure of a gas flare tip used in Qatar oil and gas offshore industry was investigated throughout this study. The design lifetime of the flare was fifteen years; however, it manifested immature failure resulting in a reduction of its lifetime to ten years. The flare is composed of different parts where the upper flare body and wind deflector showed failure while other components were still healthy. The material used for the aforementioned failed parts was Incoloy 800H, which is a highly corrosion and high-temperature resistant steel alloy. The material was rolled up and welded together with different welding joints. The root cause of failure was identified by using chemical analysis and microstructural and mechanical characterizations. For the mechanical characterization, an optical microscope (OM) and scanning electron microscope (SEM) equipped with energy dispersive spectroscopy (EDS) analyses were used for the specimen extracted from the failed part in order to ensure that the material mentioned by the manufacturer demonstrated the same metallurgical properties. For the mechanical characterization, two sets of specimens were used, one close to the failure region and the other far from the failure area. The chemical analysis revealed that the material was truthfully Incoloy 800H. The mechanical examination results showed a significant reduction of mechanical properties, i.e., the ultimate tensile strength (UTS) and microhardness dropped by 44% and 41% for samples close and far from the failure regions, respectively. Careful examination of the failed parts indicated that failure mostly took place in the vicinity of the welds, in particular near the joints. Improper joint designs, as well as a number of joints being designed in tiny areas, worsened the harmful effect of the heat-affected zone (HAZ), resulting in crack nucleation in the HAZ regions. The effect of welding in a combination of harsh service conditions of flare caused further crack extension where they merged, resulting in final immature failure.

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