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1.
Ann Anat ; 252: 152185, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37944830

RESUMO

3-acetylpyridine (3-AP) is a neurotoxin that is known to mainly affect the inferior olivary nucleus (ION) in the brain stem. Although several studies have explored the effect of this neurotoxin, still further investigation is required to understand the impact of this toxin on different parts of the brain. In this research, two groups of rats were studied, the 3-AP-treated and the control groups. Behavioral, stereological, and immunohistochemical analyses were performed. The locomotor activity of the 3-AP-treated rats decreased whereas their anxiety levels were higher than in normal controls. Also, memory performance was impaired in animals in the 3-AP group. Microscopic observations showed a decline in the numerical density of neurons in the hippocampus and striatum along with gliosis. Although this toxin is used to affect the ION, it exerts a neurotoxic effect on different brain regions.


Assuntos
Encéfalo , Neurotoxinas , Ratos , Masculino , Animais , Neurotoxinas/toxicidade , Hipocampo , Piridinas/toxicidade
2.
Toxicol Res (Camb) ; 12(5): 783-795, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37915479

RESUMO

The present study was designed to evaluate whether elderberry (EB) effectively reduces inflammation and oxidative stress in hippocampal cells to modify seizure damage. Seizure was induced in rats by the injection of pentylenetetrazol (PTZ). In the Seizure + EB group, EB powder was added to the rats' routine diet for eight consecutive weeks. The study included several behavioral tests, immunohistopathology, Voronoi tessellation (to estimate the spatial distribution of cells in the hippocampus), and Sholl analysis. The results in the Seizure + EB group showed an improvement in the behavioral aspects of the study, a reduction in astrogliosis, astrocyte process length, number of branches, and intersections distal to the soma in the hippocampus of rats compared to controls. Further analysis showed that EB diet increased nuclear factor-like 2 expression and decreased caspase-3 expression in the hippocampus in the Seizure + EB group. In addition, EB protected hippocampal pyramidal neurons from PTZ toxicity and improved the spatial distribution of hippocampal neurons in the pyramidal layer and dentate gyrus. The results of the present study suggest that EB can be considered a potent modifier of astrocyte reactivation and inflammatory responses.

3.
Metab Brain Dis ; 38(8): 2735-2750, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37851137

RESUMO

Epilepsy significantly reduces the patient's quality of life, and we still need to develop new therapeutic approaches to control it. Transplantation of cells such as Sertoli cells (SCs), having a potent ability to release a variety of growth and immunoprotective substances, have made them a potential candidate to deal with neurological diseases like epilepsy. Hence, this study aims to evaluate whether SCs transplant effectively protects the hippocampus astrocytes and neurons to oppose seizure damage. For this purpose, the effects of bilateral intrahippocampal transplantation of SCs were investigated on the rats with the pentylenetetrazol (PTZ) induced seizure. After one-month, post-graft analysis was performed regarding behavior, immunohistopathology, and the distribution of the hippocampal cells. Our findings showed SCs transplantation reduced astrogliosis, astrocytes process length, the number of branches, and intersections distal to the soma of the hippocampus in the seizure group. In rats with grafted SCs, there was a drop in the hippocampal caspase-3 expression. Moreover, the SCs showed another protective impact, as shown by an improvement in pyramidal neurons' number and spatial distribution. The findings suggested that SCs transplantation can potently modify astrocytes' reactivation and inflammatory responses.


Assuntos
Epilepsia , Células de Sertoli , Masculino , Ratos , Humanos , Animais , Células de Sertoli/patologia , Qualidade de Vida , Convulsões/tratamento farmacológico , Epilepsia/tratamento farmacológico , Hipocampo/metabolismo , Morte Celular , Amnésia/metabolismo
4.
Metab Brain Dis ; 38(5): 1555-1572, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36877342

RESUMO

Irritable bowel syndrome (IBS) is related to a problem in the gut-brain axis. This experimental research aimed to shed light on the potential therapeutic application of elderberry (EB), which can work on the axis and get better the IBS symptoms. There were three groups (36 Sprague-Dawley rats) in this experiment, including control, IBS, and IBS with EB diet (IBS + EB). Making use of intracolonic instillation of 1 ml of 4% acetic acid for 30 s, IBS was induced. 7 days later, the EB extract (2%) was added to the diets of all animals for 8 weeks. Some histological, behavioral, and stereological techniques were used to detect the effects of EB on the gut and brain tissues. The findings showed that the EB diet improved locomotion and decreased anxiety-like behavior in the rat models of IBS. Moreover, the diet dropped the expression of TNF-α and increased mucosal layer thickness and the number of goblet and mast cells in colon tissue samples. In the hippocampal samples, administration of EB prevented astrogliosis and astrocyte reactivity. Although hippocampal and cortical neurons decreased markedly in the IBS group, EB prevented the drop in the number of neurons. Although lots of research is needed to elucidate the effectiveness of EB in IBS and its exact molecular mechanism, the result of this study showed that EB as an antioxidant and immune-modulatory agent could be a promising research target to prevent the impairment in the gut-brain axis, and could ameliorative classic IBS symptoms.


Assuntos
Disfunção Cognitiva , Síndrome do Intestino Irritável , Sambucus , Ratos , Animais , Síndrome do Intestino Irritável/tratamento farmacológico , Síndrome do Intestino Irritável/psicologia , Eixo Encéfalo-Intestino , Doenças Neuroinflamatórias , Ratos Sprague-Dawley , Disfunção Cognitiva/tratamento farmacológico , Dieta
5.
J Chem Neuroanat ; 126: 102172, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36280114

RESUMO

Reports have emerged on the sudden opioid-induced auditory hearing loss, and the underlying pathology is not fully understood. The present study aimed to determine the mechanism of action of these drugs in the inner ear. For this purpose, 20 rats were treated with 50 mg/kg tramadol daily for three weeks. Next, the stereological and immunohistochemical alteration of the inner hair cells under chronic exposure to tramadol was evaluated. The results revealed that tramadol induced hair cell degeneration and decreased bipolar neurons of the spiral ganglion and the thickness of stria vascularis. Moreover, immunohistochemistry showed that tramadol caused apoptosis in inner hair cells and bipolar neurons. These findings indicate that tramadol induces apoptosis in auditory hair cells, suggesting that tramadol may cause hearing loss and ototoxicity.


Assuntos
Perda Auditiva , Tramadol , Ratos , Masculino , Animais , Tramadol/toxicidade , Células Ciliadas Auditivas , Estria Vascular/patologia , Apoptose , Perda Auditiva/patologia
6.
J Chem Neuroanat ; 120: 102071, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35051594

RESUMO

Cell replacement therapy (CRT) is one of the most effective approaches used to alleviate symptoms of neurodegenerative syndromes such as cerebellar ataxia (CA). Human olfactory epithelium mesenchymal stem cells (OE-MSCs) have been recognized as a promising candidate for CRT, due to their distinctive features including immunomodulatory properties and ease of accessible compared to other types of MSCs. Hence, the main goal of our study was to explore the impacts of OE-MSCs transplantation on behavioral, structural, and histological deficiencies in a rat model of CA. After obtained an informed consent from volunteers, OE-MSCs were obtained from their nasal cavity. Then, OE-MSCs were characterized by the positive expression of CD73, CD90, and CD105 as MSCs as well as nestin and vimentin as primitive neuroectodermal stem cells markers. Then, the animals were randomized into three control, 3-acetylpyridine (3-AP) treated, and 3-AP + cell groups. In both experimental groups, the rats received intraperitoneal injection of 3-AP (75 mg/kg), followed by the implantation of OE-MSCs into the cerebellum of 3-AP + cell group. The impact of engrafted OE-MSCs on motor coordination and performance along with biochemical, immunohistochemical, and stereological changes in the cerebellum of the rat models of CA were investigated. According to our findings, the administration of 3-AP decreased the cerebellar GSH concentration. The injection of 3-AP also altered the morphological characteristics of the cerebellar Golgi cells. On the other hand, OE-MSCs transplantation improved motor coordination in CA. Besides, the implantation of OE-MSCs reduced caspase-3 expression and microglia proliferation in the cerebellum upon 3-AP administration. Finally, the transplant of OE-MSCs protected Purkinje cells against 3-AP toxicity. In sum, the present study revealed considerable advantages of OE-MSCs in managing CA animal model.


Assuntos
Ataxia Cerebelar , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Animais , Humanos , Ratos , Ataxia Cerebelar/terapia , Células-Tronco Mesenquimais/metabolismo , Mucosa Olfatória
7.
Reprod Sci ; 29(12): 3373-3386, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35088364

RESUMO

Over the past years, several studies have also reported the adverse effects of hyperthermia on normal testicular tissues in several species including mice, rats, and humans. These deleterious impacts include temporarily drop in relative weight of testis along with a temporary partial or complete infertility. Sambucus nigra, also known as elderberry or sweet elder, is a source of bioactive compounds that has drawn growing attention for its potential beneficial effects in preventing and treating several diseases. This experimental research divided 30 mice into the following three groups: (1) control, (2) hyperthermia, and (3) hyperthermia receiving elderberry diet for 35 days. Scrotal hyperthermia was induced by water bath with 43 °C for 30 min. Then, the mice were euthanized, and their sperm samples were collected for sperm parameters analysis. Then, we took the testis samples for histopathological experimentations, immunohistochemistry against TNF-α and caspase-3 and serum testosterone, FSH and LH levels. Our outputs indicated that elderberry diet could largely improve the sperms parameters and stereological parameters, like spermatogonia, primary spermatocyte, round spermatid, and Leydig cells together with an increasing level of the serum testosterone compared to the scrotal hyperthermia induced mice. In addition, it was found that the expression of TNF-α and caspase-3 significantly decreased in the treatment groups by elderberry diet compared to the scrotal hyperthermia-induced mice. In conclusion, it could be concluded that elderberry diet may be regarded as an alternative treatment for improving the spermatogenesis process in the scrotal hyperthermia induced mice.


Assuntos
Sambucus , Animais , Masculino , Camundongos , Caspase 3/metabolismo , Dieta , Sambucus/metabolismo , Sementes/metabolismo , Espermatogênese , Espermatozoides/metabolismo , Testículo/metabolismo , Testosterona , Fator de Necrose Tumoral alfa/metabolismo
8.
J Biomed Mater Res B Appl Biomater ; 110(5): 1001-1011, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34846808

RESUMO

This study was based on in vivo assessment of bone regeneration capacity of synthesized porous ß-tricalcium phosphate (ß-TCP) nanocomposite granules and aimed to explore the effects of fabricated ß-TCP granules reinforced with layered double hydroxides (LDH) nanoclay compared to ß-TCP granules, in terms of osteoconductivity and biodegradability. Granules with diameters of 2-3 mm were implanted into cavities drilled in rabbit distal femur and were left in situ for up to 3 months. The mechanical study demonstrated that the presence of LDH nanoparticles in ß-TCP granules resulted in a significant increase in compressive modulus from 174.4 to 231.4 MPa, while the porosity was constant at 76%-80%. The results revealed that the obtained granules showed no cytotoxicity. In this study, x-ray radiographic, micro-computed tomography, and histological staining analysis were taken to evaluate the percentage of bone ingrowth and biodegradability of the porous granules. The results exhibited that both granules support bone regeneration and also the amount of new bone formation in the bone defect filled with both granules was almost six times higher than the empty defects. Although no significant difference in bone formation for two different granules was observed, a higher biodegradability was detected in ß-TCP granules in comparison to ß-TCP/LDH granules. Overall, the addition of LDH nanoclay (10%) enhanced the physicochemical and mechanical properties of ß-TCP granules while it is biological and osteoconductity properties have been maintained and its biodegradation rate has been decreased.


Assuntos
Substitutos Ósseos , Nanocompostos , Animais , Regeneração Óssea , Substitutos Ósseos/farmacologia , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Hidróxidos/farmacologia , Coelhos , Microtomografia por Raio-X
9.
J Biosci ; 462021.
Artigo em Inglês | MEDLINE | ID: mdl-34475317

RESUMO

This study aimed to examine the expression of the genes associated with different development stages of primordial germ cells (PGCs) in differentiating mouse embryonic stem cells (mESCs). The cells were cultured in three groups of control, 10-8 M of all-trans retinoic acid and the combination of 10-7 M of Progesterone and retinoic acid for 7, 12, 17, and 22 days. Immunofluorescent and Quantitative RT-PCR were used to evaluate the effect of progesterone on the differentiation of mESCs into primordial germ cells. RA-treated cells exhibited increased expression of Fragilis, Stella, Dazl, Stra8, Sycp3, and Gdf9 genes and decreased expression of Oct4, Mvh genes compared to the non-treated controls. Furthermore, RA in combination with progesterone (RA?P) led to increased expression of Oct4, Fragilis, Stella, Dazl, Sycp3, Gdf9 and decreased expression of Mvh, and Stra8 genes compared to the RA-treated scenario. Immunofluorescence detection of Stella and Mvh showed that the expression levels of the cells treated with RA+P are much higher than those of the other groups. Our project showed that under the influence of the induced factors, mESCs can spontaneously differentiate into germ cells. Also, the combination of RA+P can enhance and accelerate the differentiation of mESCs into germ cells.


Assuntos
Células-Tronco Embrionárias Murinas/efeitos dos fármacos , Progesterona/farmacologia , Tretinoína/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Células Germinativas , Camundongos , Células-Tronco Embrionárias Murinas/fisiologia
10.
Neurosci Lett ; 764: 136246, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34530114

RESUMO

Choroid plexus (CP) is the principal source of cerebrospinal fluid. CP can produce and release a wide range of materials including growth factors, neurotrophic factors, etc. all of which play an important role in the maintenance and proper functioning of the brain. Methamphetamine (METH) is a CNS neurostimulant that causes brain dysfunction. Herein, we investigated the potential effects of METH exposure on CP structure and function. Stereological analysis revealed a significant alteration in CP volume, epithelial cells and capillary number upon METH treatment. Electron microscopy exhibited changes in ultrastructure. Moreover, the upregulation of neurotrophic factors such as BDNF and VEGF as well as autophagy and apoptosis gene following METH administration were observed. We also identified several signaling cascades related to autophagy. In conclusion, gene expression changes coupled with structural alterations of the CP in response to METH suggested METH-induced autophagy in CP.


Assuntos
Estimulantes do Sistema Nervoso Central/toxicidade , Plexo Corióideo/efeitos dos fármacos , Metanfetamina/toxicidade , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Autofagia/efeitos dos fármacos , Autofagia/genética , Fator Neurotrófico Derivado do Encéfalo/análise , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Caspase 3/análise , Caspase 3/metabolismo , Estimulantes do Sistema Nervoso Central/administração & dosagem , Plexo Corióideo/citologia , Plexo Corióideo/patologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Células Epiteliais/ultraestrutura , Injeções Intraperitoneais , Masculino , Metanfetamina/administração & dosagem , Microscopia Eletrônica de Transmissão , Ratos , Regulação para Cima/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/análise , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
Brain Res ; 1762: 147444, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33745925

RESUMO

Huntington's disease (HD) is an inherited neurodegenerative disorder which begins in the striatum and then spreads to other neural areas. Known as a progressive movement cognitive disorder, HD has no efficient therapy. Although the exact mechanism of HD is still unknown, several different etiological processes such as oxidative stress have been shown to play critical roles. Also, the current evidence indicates a strong correlation between immune activation and neural damage induced by neuroinflammatory and apoptotic agents in neurodegenerative disorders. Thus, natural products like Elderberry (EB) could be considered as a novel and potential therapeutic candidate for the treatment of this disease. In this study EB was added to the daily ration of ordinary rats for two months in order to ameliorate inflammatory and oxidative responses in rats injected with 3-nitropropionic acid (3-NP) in an experimental model of HD. Using Rotarod and electromyography setups, we showed that EB diet significantly recovered motor failure and muscle incoordination in 3-NP injected rats compared to the control group. Also, the molecular findings implied that EB diet led to a significant drop in 3-NP induced growth in caspase-3 and TNF-α concentration. The treatment also improved striatal antioxidative capacity by a significant reduction in ROS and a remarkable rise in GSH, which might be correlated with motor recovery in the tests. In sum, the findings demonstrate the advantages of EB treatment in the HD rat model with a score of beneficial anti-oxidative and anti-inflammatory effects.


Assuntos
Doença de Huntington/induzido quimicamente , Doença de Huntington/dietoterapia , Atividade Motora/fisiologia , Nitrocompostos/toxicidade , Estresse Oxidativo/fisiologia , Propionatos/toxicidade , Sambucus , Animais , Morte Celular/fisiologia , Modelos Animais de Doenças , Estimulação Elétrica/métodos , Eletromiografia/métodos , Doença de Huntington/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
12.
Mol Biotechnol ; 63(6): 477-490, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33755861

RESUMO

One of the most important challenges facing tissue engineering researches is the scaffold design with optimum physical and mechanical properties for growth and proliferation of cells, and tissue formation. The aim of this study was to produce a novel nanocomposite containing ß-tricalcium phosphate and layered double hydroxide (ß-TCP-LDH) and analyzing the capacity of its osteogenic activity in vitro. In this paper, ß-tricalcium phosphate and layered double hydroxide powders were synthesized by co-precipitation processes. Then, the porous nanocomposite granules were prepared by the polyurethane sponge replication method. In this study, four kinds of ß-TCP granules containing LDHs nanoparticles (ranging from 0.1 to 10 wt%) have been prepared. X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX) analyses were selected to study the phase structure, morphology, and phase distribution, respectively. Physicochemical characterizations demonstrated that the granules were synthesized successfully. Interconnected macro pores ranging over 200-500 µm were observed for all kinds of granules. SEM micrographs showed that human mesenchymal stem cells (hMSCs) were attached to the surfaces of the granules and proliferated in good shape. The results warranted that the synthesized granules exhibited good biocompatibility and mineralization. Based on the results of compressive strength and porosity tests, the most suitable type of granule is ß-TCP/LDH 10 wt% with 77% porosity and compressive modulus of 231.4 MPa, which can be utilized in bone tissue engineering. To our knowledge, layered double hydroxides have not previously been incorporated into tricalcium phosphate granules for bone grafting. Also, this study is the first report on the effects of LDH on the mechanical properties and porosity of ß-TCP granules. Our results demonstrated that ß-TCP/LDH nanocomposite granule has a great potential for bone defects regeneration and tissue engineering applications.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Engenharia Tecidual , Alicerces Teciduais/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Regeneração Óssea/genética , Osso e Ossos/química , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Humanos , Hidróxidos/química , Hidróxidos/farmacologia , Nanocompostos/química , Porosidade
13.
Neurosci Res ; 170: 133-144, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33359180

RESUMO

Stem cell-based therapy has recently offered a promising alternative for the remedy of neurodegenerative disorders like Huntington's disease (HD). Herein, we investigated the potential ameliorative effects of implantation of dental pulp stem cells (DPSCs) in 3-nitropropionic acid (3-NP) rat models of HD. In this regard, human DPSCs were isolated, culture-expanded and implanted in rats lesioned with 3-NP. Post-transplantation examinations revealed that DPSCs were able to survive and augment motor skills and muscle activity. Histological analysis showed DPSCs treatment hampered the shrinkage of the striatum along with the inhibition of gliosis and microgliosis in the striatum of 3-NP rat models. We also detected the downregulation of Caspase-3 and pro-inflammatory cytokines such as TNF and IL-1ß upon DPSCs grafting. Overall, these findings imply that the grafting of DPSCs could repair motor-skill impairment and induce neurogenesis, probably through the secretion of neurotrophic factors and the modulation of neuroinflammatory response in HD animal models.


Assuntos
Doença de Huntington , Animais , Atrofia , Polpa Dentária , Modelos Animais de Doenças , Humanos , Doença de Huntington/induzido quimicamente , Doença de Huntington/terapia , Inflamação/induzido quimicamente , Nitrocompostos , Propionatos , Ratos , Células-Tronco
14.
Biologicals ; 56: 39-44, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30309678

RESUMO

Generation of germ cells from embryonic stem cells in vitro could have great application for treating infertility. The temporal expression profile of several genes was expressed at different stages of germ cell development and examined in differentiation the mouse embryonic stem cells. Cells were treated in three groups of control, with 10-8 M of all-trans retinoic acid and the combination of 10-9 M of 17ß-Estradiol and retinoic acid for 7, 12, 17 or 22 days. Quantitative RT-PCR and Immunofluorescent were used to investigate the possible inductive effects of estrogen on mouse embryonic stem cell-derived primordial germ cells. mRNA expression of Oct4 and Dazl were downregulated in embryonic stem cells by the retinoic acid group, whereas Mvh transcription was reduced by retinoic acid and estrogen group in these cells compared to the control group. But, retinoic acid with estrogen group-treated cells exhibited increased mRNA expression of Stra8, Fragilis, Sycp3, GDF9, and Stella compared to untreated controls. The expression of Stella and Mvh proteins were remarkably increased in cell colonies. This study shows that estrogen affects the expression of specific markers of primordial germ cells. Also, estrogen and retinoic acid speed up and increase the level of expression of specific markers.


Assuntos
Estradiol/farmacologia , Estrogênios/farmacologia , Expressão Gênica/efeitos dos fármacos , Células Germinativas/crescimento & desenvolvimento , Células-Tronco Embrionárias Murinas/efeitos dos fármacos , Tretinoína/farmacologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Proteínas de Ciclo Celular , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Células Cultivadas , Proteínas Cromossômicas não Histona , RNA Helicases DEAD-box/genética , Proteínas de Ligação a DNA , Células Germinativas/citologia , Células Germinativas/metabolismo , Fator 9 de Diferenciação de Crescimento/genética , Proteínas de Membrana/genética , Camundongos , Células-Tronco Embrionárias Murinas/citologia , Células-Tronco Embrionárias Murinas/metabolismo , Proteínas Nucleares/genética , Proteínas Repressoras/genética
15.
Int J Nanomedicine ; 13: 4575-4589, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30127607

RESUMO

INTRODUCTION: The application of nanoparticles (NPs) in medicine and biology has received great interest due to their novel features. However, their adverse effects on the biological system are not well understood. MATERIALS AND METHODS: This study aims to evaluate the effect of cerium oxide nanoparticles (CNPs) on conformational changes of human hemoglobin (HHb) and lymphocytes by different spectroscopic (intrinsic and synchronous fluorescence spectroscopy and far and near circular dichroism [CD] spectroscopy), docking and cellular (MTT and flow cytometry) investigations. RESULTS AND DISCUSSION: Transmission electron microscopy (TEM) showed that CNP diameter is ~30 nm. The infrared spectrum demonstrated a strong band around 783 cm-1 corresponding to the CNP stretching bond. Fluorescence data revealed that the CNP is able to quench the intrinsic fluorescence of HHb through both dynamic and static quenching mechanisms. The binding constant (Kb ), number of binding sites (n), and thermodynamic parameters over three different temperatures indicated that hydrophobic interactions might play a considerable role in the interaction of CNPs with HHb. Synchronous fluorescence spectroscopy indicated that microenvironmental changes around Trp and Tyr residues remain almost unchanged. CD studies displayed that the regular secondary structure of HHb had no significant changes; however, the quaternary structure of protein is subjected to marginal structural changes. Docking studies showed the larger CNP cluster is more oriented toward experimental data, compared with smaller counterparts. Cellular assays revealed that CNP, at high concentrations (>50 µg/mL), initiated an antiproliferative response through apoptosis induction on lymphocytes. CONCLUSION: The findings may exhibit that, although CNPs did not significantly perturb the native conformation of HHb, they can stimulate some cellular adverse effects at high concentrations that may limit the medicinal and biological application of CNPs. In other words, CNP application in biological systems should be done at low concentrations.


Assuntos
Fenômenos Biofísicos , Cério/química , Simulação de Acoplamento Molecular , Nanopartículas/química , Apoptose , Sítios de Ligação , Dicroísmo Circular , Hemoglobinas/metabolismo , Humanos , Linfócitos/metabolismo , Nanopartículas/ultraestrutura , Tamanho da Partícula , Ligação Proteica , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
16.
J Clin Monit Comput ; 31(5): 1043-1052, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27590919

RESUMO

With the motivation of providing safety for a patient under anesthesia, this paper suggests conditions for evaluating the correctness of an available user interface for systems under shared control based on observability and predictability requirements. Situation awareness is necessary for the user to make correct decisions about the inputs. In this article, we develop a technique to investigate the conditions under which an anesthetists can attain situation awareness about a limited but important aspect of anesthesia, namely depth of hypnosis (DOH). Furthermore, we consider that, in practice, to attain situation awareness, the estimation of the task states does not necessarily need to be precise but can be bounded within certain margins. Hence, attaining situation awareness about DOH is modeled as a bounded-error delayed functional observation/prediction. Unless such an observer/predictor exists for a system with a given user-interface, the safety of the operation may be compromised. The suggested technique proves that, in order to provide safety for the patient under anesthesia, it is necessary for the anesthetist to have access to the predictive information from a clinical decision support system.


Assuntos
Anestesia Geral/métodos , Hipnose , Monitorização Intraoperatória/métodos , Algoritmos , Anestesiologia/métodos , Sistemas de Apoio a Decisões Clínicas , Humanos , Aprendizagem , Modelos Teóricos , Reprodutibilidade dos Testes , Interface Usuário-Computador
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