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1.
J Chem Neuroanat ; : 101946, 2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33745942

RESUMO

Maternal diabetes during pregnancy affects the development of hippocampus in the offspring. Brain-derived neurotrophic factor (BDNF) has received increasing attention for its role in regulating the survival and differentiation of neuronal cells in developing and adult brain. In the current study, we evaluated the effects of maternal diabetes and insulin treatment on expression and distribution pattern of BDNF in the hippocampus of neonatal rats at the first two postnatal weeks. We found no differences in hippocampal expression of BDNF between diabetics with normal control or insulin treated neonatal rats at postnatal day (P0) (P > 0.05 each). Nevertheless, there was a marked BDNF downregulation in both sides' hippocampi of male/female diabetic group in two-week-old offspring (P ≤ 0.05 each). Furthermore, the numerical density of BDNF+ cells was significantly reduced in the right/left dentate gyrus (DG) of male and female newborns born to diabetic animals at all studied postnatal days (P ≤ 0.05 each). In addition, a lower number of reactive cells have shown in the all hippocampal subareas in the diabetic pups at P14 (P ≤ 0.05 each). Our results have demonstrated that the insulin-treatment improves some of the negative impacts of diabetes on the expression of hippocampal BDNF in the newborns. We conclude that diabetes in pregnancy bilaterally disrupts the expression of BDNF in the hippocampus of the both male and female newborns at early postnatal days. In addition, good glycemic control by insulin in the most cases is sufficient to prevent the alterations in expression of BDNF protein in developing hippocampus.

2.
Cell Mol Neurobiol ; 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33651238

RESUMO

The serotonergic system extends throughout the central nervous system (CNS) and the gastrointestinal (GI) tract. In the CNS, serotonin (5-HT, 5-hydroxytryptamine) modulates a broad spectrum of functions, including mood, cognition, anxiety, learning, memory, reward processing, and sleep. These processes are mediated through 5-HT binding to 5-HT receptors (5-HTRs), are classified into seven distinct groups. Deficits in the serotonergic system can result in various pathological conditions, particularly depression, schizophrenia, mood disorders, and autism. In this review, we outlined the complexity of serotonergic modulation of physiologic and pathologic processes. Moreover, we provided experimental and clinical evidence of 5-HT's involvement in neuropsychiatric disorders and discussed the molecular mechanisms that underlie these illnesses and contribute to the new therapies.

3.
Mater Sci Eng C Mater Biol Appl ; 121: 111855, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33579488

RESUMO

Mechanical properties of tissue engineering nanofibrous scaffolds are of importance because they not only determine their ease of application, but also influence the environment for cell growth and proliferation. Cellulose nanocrystals (CNCs) are natural renewable nanoparticles that have been widely used for manipulating nanofibers' mechanical properties. In this article, cellulose nanoparticles were incorporated into poly(caprolactone) (PCL) solution, and composite nanofibers were produced. Ozawa-Flynn-Wall (OFW) methodology and X-ray diffraction were used to investigate the effect of CNC incorporation on PCL crystalline structure and its biological properties. Results showed that CNC incorporation up to 1% increases the crystallization activation energy and reduces the crystal volume, while these factors remain constant above this critical concentration. MTT assay and microscopic images of seeded cells on the nanofiber scaffolds indicated increased cell growth on the samples containing CNC. This behavior could be attributed to their greater hydrophilicity, which was confirmed using parallel exponential kinetics (PEK) model fitting to results obtained from dynamic vapor sorption (DVS) studies. Superior performance of CNC containing samples was also confirmed by in vivo implantation on full-thickness wounds. The wound area faded away more rapidly in these samples. H&E and Masson's trichrome staining showed better regeneration and more developed tissues in wounds treated with PCL-CNC1% nanofibers.

4.
BMC Neurol ; 21(1): 73, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33588777

RESUMO

BACKGROUND: New Oral Anticoagulants (NOACs) such as Rivaroxaban are introduced as alternatives to conventional vitamin-K antagonists in the long-term treatment of thrombotic events due to their lower bleeding risk. There is a lack of evidence on the effectiveness and safety of Rivaroxaban in Cerebral venous thrombosis (CVT). This study aims to assess the effectiveness and bleeding risk of Rivaroxaban in comparison with Warfarin for the treatment of CVT. MATERIALS AND METHODS: 36 patients with diagnosis of CVT were included. Clinical and background information was assessed on admission and patients were followed for at least 12 months. Measured outcomes were modified Rankin Scale (mRS), evidence of recanalization on contrast-enhanced Brain MR venography (MRV) and major or minor bleeding. Patients were divided into two groups according to the type of oral anticoagulant (Rivaroxaban vs Warfarin). Groups were compared in terms of final outcomes and side effects. RESULT: Overall, 13 (36.11%) patients received Warfarin and 23 (63.89%) received Rivaroxaban. Optimal mRS score (0-1) was attained in 9 of 10 (90%) of patients treated with Rivaroxaban and 19 of 22 (86.36%) of patients received Warfarin. MRV showed complete or partial recanalization in 12 of 14 (85.71%) patients treated with Rivaroxaban and all patients in the Warfarin group. There was no significant difference between the two groups in terms of major and minor hemorrhage. CONCLUSION: Rivaroxaban holds promise for the treatment of CVT.

5.
J Mol Neurosci ; 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33481220

RESUMO

As a complex neurodevelopmental disorder, autism affects children in three major cognitive domains including social interactions, language learning and repetitive stereotyped behaviors. Abnormal regulation of cell proliferation in the brain during the embryonic period via the TGF-ß signaling pathway and TRIM33 gene that encodes a protein with a corepressor and regulatory role in this pathway has been considered as an etiology for autism. Here, we investigated the association of a variation of TRIM33 with autism symptoms at levels of mRNA and protein expression. We used Autism Diagnostic Interview-Revised (ADI-R) and Childhood Autism Rating Scale (CARS) as behavioral diagnostic tools. Normal and autistic children were genotyped for a TRIM33 polymorphism (rs11102807), and then expression was assessed at transcriptional and translational levels. Results demonstrated that the frequency of the homozygous A allele (AA genotype of rs11102807) was significantly higher in children with autism (P < 0.001), whereas carriers of the G allele were mostly among healthy individuals. Children homozygous for the rs11102807 A allele were associated with an increase in CARS and ADI-R scores, indicating a significant correlation with autism symptoms. TRIM33 gene expression at both mRNA (P < 0.01) and protein (P < 0.001) levels was significantly higher in controls compared to autistic children. A remarkable association between higher TRIM33 gene expression at the transcriptional level and lower scores for both CARS and ADI-R was observed in non-autistic children. It seems that rs11102807 modulates the function and expression of the TRIM33 gene, implying that the A allele may increase the risk of autism in children by reducing gene expression and altering the TGF-ß signaling pathway.

6.
Neurosci Lett ; 745: 135620, 2021 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-33429001

RESUMO

BACKGROUND: Pain is one of the most common non-motor symptoms in Parkinson's disease (PD). Using an appropriate and specific measuring tool would be helpful in managing the pain. King's Parkinson's disease Pain Scale (KPPS) is an instrument designed to specifically measure pain in people with PD. PURPOSE: This study aimed to examine the psychometric properties of the Persian version of KPPS (KPPS-P) and its cut-off points for pain severity levels. METHODS: A total of 480 people with PD (with a mean (SD) age of 60.89 (10.98)) were recruited. The acceptability of KPPS-P was calculated. The structural validity and discriminant validity for different levels of pain was explored via the factor analysis, and Receiver Operating Characteristics (ROC) curves, respectively. Internal consistency, test-retest, and inter-rater reliability were estimated by Cronbach's alpha and Interclass Correlation coefficient (ICC). Convergent validity was established between KPPS-P and other scales including Visual Analog Scale-Pain, Douleur Neuropathic 4, Brief Pain Inventory, Short-form McGill Pain Questionnaire-2, and Parkinson's Disease-8. RESULTS: A significant floor effect was observed. The exploratory factor analysis revealed 4 factors. Cronbach's alpha and ICC values were higher than 0.80. The correlation range between KPPS-P and other scales was 0.35-0.76. Cut-off points of 0, 17, and 68 were obtained to discriminate pain severity levels between no pain, mild, moderate, and severe pain, respectively, with sensitivity and specificity above 0.80. CONCLUSION: Our results indicate that the Persian version of KPPS not only has acceptable psychometric properties to assess pain in PD but also has the ability to distinguish between different levels of pain severity.

7.
Neurol Sci ; 2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33241536

RESUMO

OBJECTIVE: Neuropathic pain is a type of pain reported in people with Parkinson's disease. There are various scales to evaluate the characteristics of this kind of pain. The purpose of this study was to investigate the psychometric properties of the Neuropathic Pain Symptom Inventory (NPSI), a specific scale that measures neuropathic pain in Iranian people with Parkinson's disease. METHOD: Four hundred forty-seven individuals with Parkinson's disease were recruited in the study. Acceptability, internal consistency (Cronbach's alpha), and test-retest reliability (intraclass correlation coefficient, ICC) of NPSI were calculated. Dimensionality was examined through exploratory factor analysis. For convergent validity, correlations of NPSI with Douleur Neuropathic 4, Brief Pain Inventory, King's Pain Parkinson disease Scale, and Visual Analog Scale-Pain were used. Discriminative validity and sensitivity to change between On- and Off- medication states were analyzed. RESULTS: A marked floor effect was observed for this scale (64.2%). Cronbach's alpha and ICC were 0.90 and 0.87, respectively. Items of NPSI were placed in 4 factors. A moderate to the strong association (rs = 0.55 to 0.85) between NPSI and other scales was obtained. The results of discriminative validity and sensitivity to change indicate the ability of NPSI to show differences between medication states. CONCLUSION: The results of this study suggest that NPSI has acceptable reliability, validity, and sensitivity to change, indicating that this scale is suitable for measuring neuropathic pain in Iranian people with Parkinson's disease.

8.
Rev Neurosci ; 31(6): 617-636, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32739909

RESUMO

The molecular and chemical properties of neuronal nitric oxide synthase (nNOS) have made it a key mediator in many physiological functions and signaling transduction. The NOS monomer is inactive, but the dimer form is active. There are three forms of NOS, which are neuronal (nNOS), inducible (iNOS), and endothelial (eNOS) nitric oxide synthase. nNOS regulates nitric oxide (NO) synthesis which is the mechanism used mostly by neurons to produce NO. nNOS expression and activation is regulated by some important signaling proteins, such as cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB), calmodulin (CaM), heat shock protein 90 (HSP90)/HSP70. nNOS-derived NO has been implicated in modulating many physiological functions, such as synaptic plasticity, learning, memory, neurogenesis, etc. In this review, we have summarized recent studies that have characterized structural features, subcellular localization, and factors that regulate nNOS function. Finally, we have discussed the role of nNOS in the developing brain under a wide range of physiological conditions, especially long-term potentiation and depression.

9.
Biomed Eng Online ; 19(1): 64, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32811522

RESUMO

BACKGROUND: Fear of falling (FoF) is defined as a lasting concern about falling that causes a person to limit or even stop the daily activities that he/she is capable of. Seventy percent of Parkinson's disease (PD) patients report activity limitations due to FoF. Timely identification of FoF is critical to prevent its additional adverse effects on the quality of life. Self-report questionnaires are commonly used to evaluate the FoF, which may be prone to human error. OBJECTIVES: In this study, we attempted to identify a new postural stability-indicator to objectively predict the intensity of FoF and its related behavior(s) in PD patients. METHODS: Thirty-eight PD patients participated in the study (mean age, 61.2 years), among whom 10 (26.32%) were identified with low FoF and the rest (73.68%) with high FoF, based on Falls Efficacy Scale-International (FES-I). We used a limit of stability task calibrated to each individual and investigated the postural strategies to predict the intensity of FoF. New parameters (FTRis; functional time ratio) were extracted based on the center of pressure presence pattern in different rectangular areas (i = 1, 2, and 3). The task was performed on two heights to investigate FoF-related behavior(s). RESULTS: FTR1/2 (the ratio between FTR1 and FTR2) was strongly correlated with the FES-I (r = - 0.63, p < 0.001), Pull test (r = - 0.65, p < 0.001), Timed Up and Go test (r = - 0.57, p < 0.001), and Berg Balance Scale (r = 0.62, p < 0.001). The model of FTR1/2 was identified as a best-fitting model to predicting the intensity of FoF in PD participants (sensitivity = 96.43%, specificity = 80%), using a threshold level of ≤ 2.83. CONCLUSIONS: Using the proposed assessment technique, we can accurately predict the intensity of FoF in PD patients. Also, the FTR1/2 index can be potentially considered as a mechanical biomarker to sense the FoF-related postural instability in PD patients.

10.
Int J Neurosci ; : 1-10, 2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32746675

RESUMO

AIM OF THE STUDY: In this study, we investigated the effect of long-term administration of orexin receptor 1 (OXR1) antagonist on naloxone-precipitated morphine withdrawal symptoms and nociceptive behaviors in morphine-dependent rats. MATERIALS AND METHODS: Wistar rats received subcutaneous (s.c.) injections of morphine (6, 16, 26, 36, 46, 56, and 66 mg/kg, 2 ml/kg) at an interval of 24 h for 7 days. In chronic groups, the OXR1 antagonist, SB-334867 (20 mg/kg, i.p.), or its vehicle, was injected repetitively from postnatal day 1 (PND1)-PND23 and then for the following seven days before each morphine injection. Meanwhile, in acute groups, SB-334867, or its vehicle, was administered before each morphine injection. In groups of rats that were designated for withdrawal experiments, naloxone (2.5 mg/kg, i.p.) was administered after the last injection of morphine. In the formalin-induced pain, the effect of OXR1 inhibition on the antinociceptive effects of morphine was measured by injecting formalin after the final morphine injection. RESULTS: Animals that received long-term SB-334867 administration before morphine injection demonstrated a significant reduction in chewing, defecation, diarrhea, grooming, teeth chattering, wet-dog shake, and writhing. Inhibiting OXR1 for a long time increased formalin-induced nociceptive behaviors in interphase and phase II of the formalin-induced pain. CONCLUSIONS: Our results indicated that the inhibition of OXR1 significantly reduces the development of morphine dependence and behavioral signs elicited by the administration of naloxone in morphine-dependent rats. Furthermore, the prolonged blockade of OXR1 might be involved in formalin-induced nociceptive behaviors.

11.
Pharmacol Res ; 160: 105163, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32846212

RESUMO

Extensive progress has been made to understand the pathophysiology of stroke but it is still a major cause of mortality and disability worldwide. There are few strategies for the treatment of this disease and the use of thrombolytic tissue plasminogen activator is limited due to the narrow time window. However, the administration of neuroactive steroids could be considered as a potential treatment approach to decrease ischemia-induced lesions. Neurosteroids receptors play important roles in neuroprotection mediated by these hormones. Membrane and intracellular receptors are both involved in the protective effects of estrogen and progesterone on ischemic brain injury. The intracellular receptors often regulate the gene transcription while the membrane receptors act through modulation of signal transduction pathways. Besides, allopregnanolone acts as a potent positive modulator of the GABA receptor. Moreover, the neuroprotective effects of vitamin D and dehydroepiandrosterone (DHEA) are mediated through the binding to vitamin D receptor (VDR) and several intracellular and membrane receptors, respectively. Activation of VDR could affect various processes including apoptosis, calcium metabolism, oxidative stress, immune modulation, inflammation and detoxification, and DHEA can modulate neurogenesis, neuronal function, and mitochondrial oxidative capacity. The present study aimed to describe the neuroprotective roles of the aforementioned neurosteroids with a focus on their receptors against ischemic stroke.

12.
Neuroscience ; 444: 196-208, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32717294

RESUMO

Impulsivity includes hasty actions, social intrusiveness or premature decision-making. Neuropeptides like oxytocin alleviate haste and anxiety, and affect fear conditioning. However, no investigations have been done via gene-network based approach with cognitive and interventional genetic association studies to scrutinize the link between impulsive behavior and oxytocin. Here, interactive gene network and pathways associated with impulsivity were reconstructed, and serotonin transporter gene (SLC6A4) and serotoninergic synaptic transmission were identified as the most central gene and pathway related to impulsivity. Young healthy males received intranasal oxytocin or placebo, and impulsivity was evaluated via go/no-go test. Test performance scores then were analyzed based on commission and omission errors, response inhibition and reaction time. Blood DNA was extracted and a 761 bp intronic region in oxytocin receptor (OXTR) gene was amplified and sequenced using PCR-pyrosequencing. Employing Haploview, haplotypes and linkage disequilibrium (LD) pattern among all SNPs in the target sequence were determined based on D' and LOD values, and rs2254298 with the highest LD was indicated as the tag SNP. Oxytocin group and participants with GG genotype showed a significantly decreased commission error and increased inhibition. This means that oxytocin alleviated impulsive behavior, and subjects with GG genotype had lower rate of impulsivity than those with GA and AA genotypes. rs2254298 may modulate the function or expression of the OXTR gene, implying that G allele may increase the expression of OXTR gene compared to A allele. We suggest that intranasal oxytocin may notably moderate impulsive behavior and tendency to make hasty or premature decisions.

13.
Life Sci ; 257: 118046, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32622948

RESUMO

Orexin-A is an endogenous peptide with receptors throughout the brain. According to some recent research, learning and memory are affected by the central administration of orexin; however, no study so far has investigated the long-term inhibition of the orexinergic system. The present study has evaluated the effect of pretraining administration of orexin 1 receptor (OXR1) antagonist, SB-334867, on the acquisition of memory. The Morris water maze (MWM) task was used for training and trial purposes in all groups. Memory performance was analyzed by measuring escape latency, traveled distance, and time spent in the target quadrant. Moreover, the effect of SB-334867 on phospholipase Cß3 (PLCß3) levels in the CA1 region of hippocampus slices was examined. Hippocampus slices were prepared using an immunohistochemistry (IHC) approach. SB-334867 (20 mg/kg) increased escape latency in SB-treated rats compared to SB-vehicle group (P < 0.01). SB-treated rats spent less time in the target quadrant compared to the SB-vehicle group (P < 0.001). Distance traveled in the target quadrant was significantly more in SB-treated rats compared to the SB-vehicle group (P < 0.001). Furthermore, SB-334867 decreased PLCß3 levels in the CA1 of the hippocampus (P < 0.01 and P < 0.05, respectively). Put together, our results suggest that the long-term inhibition of OXR1 plays a prominent role in spatial learning and memory, probably by attenuating PLCß3 in CA1 neurons.


Assuntos
Memória/efeitos dos fármacos , Memória/fisiologia , Fosfolipase C beta/metabolismo , Animais , Benzoxazóis/farmacologia , Hipocampo/metabolismo , Hipocampo/fisiologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Naftiridinas/farmacologia , Receptores de Orexina/metabolismo , Orexinas/metabolismo , Fosfolipase C beta/fisiologia , Ratos , Ratos Wistar , Ureia/análogos & derivados , Ureia/farmacologia
14.
Cell Tissue Res ; 381(3): 397-410, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32696217

RESUMO

Spinal cord injury (SCI) is a devastating condition with a growing incidence in developing countries. The activity of inflammasome complexes initiates neuroinflammation, which is a key player in SCI pathogenesis. Here, NLRP1, NLRP3, and absent in melanoma 2 (AIM2) inflammasome complexes were assessed in the contusive (T6) SCI rats for their expression profiles and their response to hormonal therapy (10 mg/kg melatonin or 25 µg/kg 17ß-estradiol [E2] every 12 h until 72 h). Two phases was considered in this study: the dominant time of inflammasome activation, which was 72 h post-SCI and the response from each complex to hormonal therapy at this time. Gene and protein expressions of NLRP1, NLRP3, AIM2, ASC, and caspase-1 were evaluated by real-time PCR (for gene analysis), western blot, and immunohistochemistry (IHC), and biochemical presence of IL-18 and IL-1ß in spinal cord tissue homogenates was analyzed by enzyme-linked immunosorbent assay (ELISA). The whole inflammasome complexes showed high expressions in the SCI group, while after hormonal therapy, these alterations were counteracted, which were more conspicuous for the NLRP1 and NLRP3. Melatonin had no predilection over E2 for such effect. Finally, the expression profile of signaling related to the synthesis (TLR4/NF-κB) and activation (NADPH oxidase 2 [NOX2]/TXNIP) of inflammasome complexes was surveyed, and there were low activities for the two pathways in SCI rats that underwent hormone therapy. From the findings, it is concluded that both melatonin and E2 are efficient to target inflammasome activation in the SCI rats.

15.
Cell Mol Neurobiol ; 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32696288

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disorder, in which amyloid precursor protein (APP) misprocessing and tau protein hyperphosphorylation are well-established pathogenic cascades. Despite extensive considerations, the central mediator of neuronal cell death upon AD remains under debate. Therefore, we examined the direct interplay between tauopathy and amyloidopathy processes. We employed primary culture neurons and examined pathogenic P-tau and Aß oligomers upon hypoxia treatment by immunofluorescence and immunoblotting. We observed both tauopathy and amyloidopathy processes upon the hypoxia condition. We also applied Aß1-42 or P-tau onto primary cultured neurons. We overexpressed P-tau in SH-SY5Y cells and found Aß accumulation. Furthermore, adult male rats received Aß1-42 or pathogenic P-tau in the dorsal hippocampus and were examined for 8 weeks. Learning and memory performance, as well as anxiety behaviors, were assessed by Morris water maze and elevated plus-maze tests. Both Aß1-42 and pathogenic P-tau significantly induced learning and memory deficits and enhanced anxiety behavior after treatment 2 weeks. Aß administration induced robust tauopathy distribution in the cortex, striatum, and corpus callosum as well as CA1. On the other hand, P-tau treatment developed Aß oligomers in the cortex and CA1 only. Our findings indicate that Aß1-42 and pathogenic P-tau may induce each other and cause almost identical neurotoxicity in a time-dependent manner, while tauopathy seems to be more distributable than amyloidopathy.

16.
J Telemed Telecare ; : 1357633X20919308, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32393139

RESUMO

INTRODUCTION: The use of telemedicine in orthopaedics can provide high-quality orthopaedic services to patients in remote areas. Tele-orthopaedics is widely acknowledged for decreasing travel, time and cost, increasing accessibility and quality of care. In the absence of a comprehensive review on tele-orthopaedics applications and services, here, we systematically identify and classify the tele-orthopaedic applications and services and provide an overview of the trends in the field. METHODS: In this study, a systematic mapping was conducted to answer six research questions, we searched the databases Scopus, PubMed, IEEE Digital Library and Web of Science up to 2019. Consequently, 77 papers were screened and selected on the basis of specific inclusion and exclusion criteria. RESULTS: We found that mobile-based teleconsultation was mostly asynchronous, while non-mobile teleconsultation was synchronous. The results showed that the physician-patient relationship was more common than other interactions, such as physician-physician and physician-robot interactions. In addition, more than half of the services provided by tele-orthopaedics have been used for orthopaedic diseases/traumas in which joint replacement and fracture reduction have been the most important orthopaedic procedures. It has been noted that more attention has been paid to tele-orthopaedics in developed countries such as the USA, Australia, Canada and Finland. DISCUSSION: Telemonitoring (teleconsultation and telemetry) and telesurgery (telerobotics and telementoring) were found to be the two major forms of tele-orthopaedics. Mobile phones were used asynchronously in most of the teleconsultations. The development of different applications may result in the use of multiple smartphones applications in real-time teleconsultation. The use of smartphones is expected to increase in the near future.

17.
Mol Cell Biochem ; 470(1-2): 29-39, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32388790

RESUMO

Logistic complexities of heart transplantation embossed the necessity of utilizing novel methods, which enable heart regeneration. Human cardiosphere-derived cells (hCDCs) are taken into consideration as a promising cell resource in cell therapy in recent years. In this study, we designed an electrochemical stimulation system, which sends square pulses to the hCDCs and records their electrical response. Morphology, viability and differentiation of hCDCs are monitored at certain time courses of the treatment. Differentiating hCDCs aligned perpendicularly with respect to the direction of applied electric current, and obtained a spindle-like morphology, while they remained viable. At the same time, specific cardiac marker genes including GATA4, cTnT and α-MHC showed a considerable up-regulation. Our findings confirm that hCDCs differentiate to committed cardiomyocytes when hCDCs receive an electrical energy of 0.06 - 0.12 Wh. This amount of electrical energy could be applied to the stem cells using versatile electrical stimulation patterns via commercially available devices.

18.
Int J Pharm ; 577: 119037, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31953081

RESUMO

Spinal Cord Injury (SCI) is one of the leading causes of physical disability. In this study, spherical PLGA nanoparticles (NPs) containing ChABC enzyme were manufactured and fully characterized for SCI therapy. The NPs were used in the rat's contused spinal cord to assess the functional improvement and scar digestion. Twenty-three adult male Wistar rats (275 ± 25 g) were assigned into four groups of control, sham, blank-treated particle, and ChABC-treated particle. Throughout the survey, the BBB scores were obtained for all the groups. Finally, the injured sections of animals were dissected, and histological studies were conducted using Luxol fast blue and Bielschowsky. The biocompatibility and non-toxicity effects of the NPs on olfactory ensheathing cells (OECs) were confirmed by the MTT test. The flow-cytometry revealed the purity of cultured OECs with p75+/GFAP+ at around 87.9 ± 2.4%. Animals in the control and the blank-treated groups exhibited significantly lower BBB scores compared with the ChABC-treated particle group. Histological results confirmed the induced contusion models in the injured site. Myelin was observed in the treated groups, especially when the ChABC-loaded nanoparticles were utilized. The immunohistochemistry results indicated the scar glial degradation in animals treated by the ChABC-loaded particles. According to this study, the loaded particles can potentially serve as a suitable candidate for spinal cord repair, functional recovery and axonal regeneration.

19.
Biomed Mater ; 15(3): 035014, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-31896091

RESUMO

Tendon tissue engineering based on stem cell differentiation has attracted a great deal of attention in recent years. Previous studies have examined the effect of cell-imprinted polydimethylsiloxane (PDMS) substrate on induction differentiation in stem cells. In this study, we used tenocyte morphology as a positive mold to create a tenocyte-imprinted substrate on PDMS. The morphology and topography of this tenocyte replica on PDMS was evaluated with scanning electron microscopy (SEM) and atomic force microscopy. The tenogenic differentiation induction capacity of the tenocyte replica in adipose tissue-derived mesenchymal stem cells (ADSCs) was then investigated and compared with other groups, including tissue replica (which was produced similarly to the tenocyte replica and was evaluated by SEM), decellularized tendon, and bone morphogenic protein (BMP)-12, as other potential inducers. This comparison gives us an estimate of the ability of tenocyte-imprinted PDMS (called cell replica in the present study) to induce differentiation compared to other inducers. For this reason, ADSCs were divided into five groups, including control, cell replica, tissue replica, decellularized tendon and BMP-12. ADSCs were seeded on each group separately and investigated by the real-time reverse transcription polymerase chain reaction (RT-PCR) technique after seven and 14 days. Our results showed that in spite of the higher effect of the growth factor on tenogenic differentiation, the cell replica can also induce tenocyte marker expression (scleraxis and tenomodulin) in ADSCs. Moreover, the tenogenic differentiation induction capacity of the cell replica was greater than tissue replica. Immunocytochemistry analysis revealed that ADSCs seeding on the cell replica for 14 days led to scleraxis and tenomodulin expression at the protein level. In addition, immunohistochemistry indicated that contrary to the promising results in vitro, there was little difference between ADSCs cultured on tenocyte-imprinted PDMS and untreated ADSCs. The results of such studies could lead to the production of inexpensive cell culture plates or biomaterials that can induce differentiation in stem cells without growth factors or other supplements.

20.
Methods ; 171: 62-67, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31302179

RESUMO

A matrix derived from natural tissue functions as a highly biocompatible and versatile scaffold for tissue engineering applications. It can act as a supportive construct that provides a niche for colonization by host cells. In this work, we describe a cost-effective, reliable and reproducible protocol for decellularization and preservation of human skin as a potential soft tissue replacement. The decellularized human skin is achieved using purely chemical agents without any enzymatic steps. The suitability of the proposed method for the preservation of the extracellular matrix (ECM) structure and its main components and integrity were evaluated using histological and immunohistochemical analysis. Cryopreservation and final sterility were conducted using programmable freeze-drying and gamma irradiation. The architecture, basement membrane and 3D structure of ECM can be successfully preserved after decellularization. Our protocol was found to be appropriate to maintain key proteins such as collagen type I, III, IV and laminin in the structure of final scaffold. This protocol offers a novel platform for the preparation of a dermal substitute for potential clinical applications. STATEMENT OF SIGNIFICANCE: Clinical application of naturally-based scaffolds for verity of health problems obliges development of a reproducible and effective technology that does not change structural and compositional material properties during scaffold preparation and preservation. Lack of an effective protocol for the production of biological products using decellularization method is still remaining. This effort is directing to solve this challenge in order to accomplish the off-the -shelf availability of decellularized dermal scaffold in market for clinical application.

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