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The fate of herpesvirus genomes following entry into different cell types is thought to regulate the outcome of infection. For the Herpes simplex virus 1 (HSV-1), latent infection of neurons is characterized by association with repressive heterochromatin marked with Polycomb silencing-associated lysine 27 methylation on histone H3 (H3K27me). However, whether H3K27 methylation plays a role in repressing lytic gene expression in non-neuronal cells is unclear. To address this gap in knowledge, and with consideration that the fate of the viral genome and outcome of HSV-1 infection could be heterogeneous, we developed an assay to quantify the abundance of histone modifications within single viral genome foci of infected fibroblasts. Using this approach, combined with bulk epigenetic techniques, we were unable to detect any role for H3K27me3 during HSV-1 lytic infection of fibroblasts. By contrast, we could detect the lesser studied H3K27me2 on a subpopulation of viral genomes, which was consistent with a role for H3K27 demethylases in promoting lytic gene expression. In addition, viral genomes co-localized with the H3K27me2 reader protein PHF20L1, and this association was enhanced by inhibition of the H3K27 demethylases UTX and JMJD3. Notably, targeting of H3K27me2 to viral genomes was enhanced following infection with a transcriptionally defective virus in the absence of Promyelocytic leukemia nuclear bodies. Collectively, these studies implicate a role for H3K27me2 in fibroblast-associated HSV genome silencing in a manner dependent on genome sub-nuclear localization and transcriptional activity. IMPORTANCE: Investigating the potential mechanisms of gene silencing for DNA viruses in different cell types is important to understand the differential outcomes of infection, particularly for viruses like herpesviruses that can undergo distinct types of infection in different cell types. In addition, investigating chromatin association with viral genomes informs on the mechanisms of epigenetic regulation of DNA processes. However, there is a growing appreciation for heterogeneity in the outcome of infection at the single cell, and even single viral genome, level. Here we describe a novel assay for quantifying viral genome foci with chromatin proteins and show that a portion of genomes are targeted for silencing by H3K27me2 and associate with the reader protein PHF20L1. This study raises important questions regarding the mechanism of H3K27me2-specific targeting to viral genomes, the contribution of epigenetic heterogeneity to herpesvirus infection, and the role of PHF20L1 in regulating the outcome of DNA virus infection.
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Herpes Simple , Herpesvirus Humano 1 , Humanos , Cromatina/metabolismo , Proteínas Cromosómicas no Histona/genética , Proteínas Cromosómicas no Histona/metabolismo , Epigénesis Genética , Fibroblastos , Herpesvirus Humano 1/fisiologíaRESUMEN
The fate of herpesvirus genomes following entry into different cell types is thought to regulate the outcome of infection. For the Herpes simplex virus 1 (HSV-1), latent infection of neurons is characterized by association with repressive heterochromatin marked with Polycomb silencing-associated lysine 27 methylation on histone H3 (H3K27me). However, whether H3K27 methylation plays a role in repressing lytic gene expression in non-neuronal cells is unclear. To address this gap in knowledge, and with consideration that the fate of the viral genome and outcome of HSV-1 infection could be heterogeneous, we developed an assay to quantify the abundance of histone modifications within single viral genome foci of infected fibroblasts. Using this approach, combined with bulk epigenetic techniques, we were unable to detect any role for H3K27me3 during HSV-1 lytic infection of fibroblasts. In contrast, we could detect the lesser studied H3K27me2 on a subpopulation of viral genomes, which was consistent with a role for H3K27 demethylases in promoting lytic gene expression. This was consistent with a role for H3K27 demethylases in promoting lytic gene expression. In addition, viral genomes co-localized with the H3K27me2 reader protein PHF20L1, and this association was enhanced by inhibition of the H3K27 demethylases UTX and JMJD3. Notably, targeting of H3K27me2 to viral genomes was enhanced following infection with a transcriptionally defective virus in the absence of Promyelocytic leukemia nuclear bodies. Collectively, these studies implicate a role for H3K27me2 in fibroblast-associated HSV genome silencing in a manner dependent on genome sub-nuclear localization and transcriptional activity.
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INTRODUCTION: Orthodontics is closely related to periodontics. The buccolingual inclination (BLI) of the incisors and deficiencies in their buccal (BHd) and lingual (LHd) cortical plate heights may affect orthodontic outcomes. Identifying risk factors that can compromise buccal or lingual bone heights may have clinical value. The literature on BLI/BHd/LHd is not only scarce but also limited to one jaw. We aimed to examine, for the first time, factors affecting BLI/BHd/LHd not evaluated before as well as other factors with scarce literature about them. METHODS: In this two-phase epidemiological and analytical study, inclinations and cortical heights of 248 incisors (bilateral centrals and laterals) were evaluated blindly on 62 randomly selected high-resolution pretreatment cone-beam computed tomography volumes (30 maxillae [13 men, 17 women], 32 mandibles [13 men, 19 women]). The sample was balanced in terms of sexes, jaws, and ages. The BLI/BHd/LHd of bilateral incisors were measured (intraobserver agreement > 95%). The effects of jaws, sexes, age, sides, and incisor types on each of the anatomical variables (BLI/BHd/LHd) were analyzed using a Mixed-Model Multiple Linear Regression analysis. Correlations among continuous variables were assessed using a Pearson coefficient (α = 0.05). RESULTS: For the maxillary centrals, BLI, BHd, and LHd were 106.79 ± 5.06, 1.94 ± 0.95, and 1.50 ± 0.76, respectively. These parameters were '110.56 ± 5.97, 1.81 ± 0.83, 1.23 ± 0.69' for the maxillary laterals; '97.64 ± 8.26, 2.98 ± 1.48, 3.46 ± 1.45' for the mandibular centrals; and '95.98 ± 6.80, 3.29 ± 1.72, and 2.73 ± 1.15' for the mandibular laterals. BLI was greater in the maxilla compared to the mandible and in the lateral incisors compared to centrals (P < 0.05). BHd was greater (more deficient) in the mandible (P = 0.000). Age, sex, or side were not associated with BLI (P > 0.05). Age, sex, side, or incisor types were not associated with BHd (P > 0.05). LHd was greater in the mandible, older individuals, and centrals (P < 0.05). There were some significant but weak correlations between BLI with BHd and especially LHd (P < 0.05). CONCLUSION: In the maxilla, but not in the mandible, incisors' BLI may determine LHd. Maxillary incisors may have greater BLIs as well as greater buccal and lingual alveolar bone heights compared to mandibular incisors. BLI might be greater in the laterals compared to the centrals in both jaws combined.
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Incisivo , Maxilar , Masculino , Femenino , Humanos , Mandíbula , Lengua , Corteza CerebralRESUMEN
Titanium dioxide nanotubes (TNT) are widely researched materials for the photocatalytic generation of free radicals, which are useful in wastewater treatment. We aimed to prepare Mo-doped TNT sheets, covered with a cellulose membrane to avoid TNT surface inactivation by protein adsorption. We studied the susceptibility of serum albumin (SA) bound to different molar ratios of palmitic acid (PA) to denaturation and fibrillation by this system, which is meant to mimic oxidative stress conditions such as non-alcoholic fatty liver disease. The results demonstrated that cellulose membrane-covered TNT successfully oxidized the SA, identified by structural changes to the protein. Increasing the molar ratio of PA to protein-enhanced thiol group oxidation while protecting the protein against structural changes. Finally, we propose that in this photocatalyzed oxidation system, the protein is oxidized by a non-adsorptive mechanism mediated by H2O2. Therefore, we suggest that this system could be used as a sustained oxidation system to oxidize biomolecules as well as potentially in wastewater treatment.
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Peróxido de Hidrógeno , Nanotubos , Oxidación-Reducción , Estrés Oxidativo , Nanotubos/química , Titanio/químicaRESUMEN
Introduction: In the present study, the effects of prenatal stress on spatial learning and memory deficit and its relationship with hippocampal insulin resistance were examined in male and female offspring. Methods: Female NMRI mice were mated with males overnight, and the 0-day of pregnancy was detected (Gestational day 0-GD0). The pregnant mice were then randomly divided into stress and control groups. The stress group received stress from the GD0 to GD10. On post natal day 30 (PND30), the offspring were divided into 4 subgroups, namely: male-control, female-control, male-stress, and female-stress. Barnes maze method was used for spatial learning evaluation. Plasma cortisol and insulin levels were measured at the beginning of the experiments. At the end of the experiments, the animals' brains were removed, and their hippocampus was extracted. The hippocampus was homogenized, and its insulin and insulin-receptor contents were evaluated. Results: The stressed animals needed more time for reaching to target hole. In addition, they spend more distance to find the target hole, which was more pronounced in the male offspring. Both plasma and hippocampal insulin content were reduced in the stressed groups. Moreover, the hippocampal insulin receptors protein was reduced in the stressed animals. There was a positive relationship between plasma and hippocampal content and memory deficit in the stressed groups. Conclusion: These results indicated that prenatal stress could induce spatial learning and memory deficit in offspring, which is associated with plasma and hippocampal insulin and receptor content reduction (hippocampal insulin resistance) in these animals. Highlights: Maternal stress is very harmful for fetus.The effect of stress is significant during the early days of gestation.This effect is due to several hormonal and neuronal disturbances including Insulin resistance.The effects of stress on the fetus is gender dependent. Plain Language Summary: The possible effectiveness of prenatal stress on learning and memory in neonates and also the changes in hippocampus as of essential part of the brain involved in learning and memory. We found that prenatal stress can reduce the insulin effects in hippocampus and it may be the main cause of stress on neonatal memory deficits.
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BACKGROUND AND OBJECTIVES: Periodontium is an important tooth-supporting tissue composed of both hard (alveolar bone and cementum) and soft (gingival and periodontal ligament) sections. Due to the multi-tissue architecture of periodontium, reconstruction of each part can be influenced by others. This review focuses on the bone section of the periodontium and presents the materials used in tissue engineering scaffolds for its reconstruction. MATERIALS AND METHODS: The following databases (2015 to 2021) were electronically searched: ProQuest, EMBASE, SciFinder, MRS Online Proceedings Library, Medline, and Compendex. The search was limited to English-language publications and in vivo studies. RESULTS: Eighty-three articles were found in primary searching. After applying the inclusion criteria, seventeen articles were incorporated into this study. CONCLUSIONS: In complex periodontal defects, various types of scaffolds, including multilayered ones, have been used for the functional reconstruction of different parts of periodontium. While there are some multilayered scaffolds designed to regenerate alveolar bone/periodontal ligament/cementum tissues of periodontium in a hierarchically organized construct, no scaffold could so far consider all four tissues involved in a complete periodontal defect. The progress and material considerations in the regeneration of the bony part of periodontium are presented in this work to help investigators develop tissue engineering scaffolds suitable for complete periodontal regeneration.
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Background: Cemento-ossifying fibroma (COF) is a type of benign fibro-osseous tumor that mainly occurs in the maxillofacial region. Bone reconstruction after the surgery is often performed with bone transplantation. However, the present case report describes the accurate diagnosis and successful surgical resection of a COF with periosteum preservation, after which the defect was completely and spontaneously filled with the newly formed bone through a natural process. Case Presentation. A 32-year-old Iranian female patient presented with a history of gradual development of painful swelling, spontaneous pain, and lower lip and chin hypoesthesia in the lower third of the left side of her face. The dome-shaped swelling was tender. The patient was suffering from renal infection and urethral prolapse and was taking folic acid. She also mentioned a positive family history of similar swellings in her mother and uncle. Intraoral examination indicated a lesion in buccal and lingual vestibules extending from the first premolar to the third molar teeth. It had a firm consistency, and the covering mucosa was normal in terms of color and texture. The aspiration test was negative. The lesion had caused severe mobility of the second premolar and first and second molar teeth. Panoramic radiography revealed an extensive well-defined unilocular radiolucency. Significant knife-edge resorption of the first and second molar roots at the involved site and thinning of the alveolar crest and inferior border of the mandible were also clear. Cone-beam computed tomography showed severe expansion in the buccal and moderate expansion in the lingual aspect, causing thinning of both the buccal and lingual cortical plates. Histopathological analysis revealed neoplastic tissue mixed with fibrous connective tissue and several round and oval-shaped calcification foci. Immunohistochemical analysis confirmed the final diagnosis (COF) with the presence of SMA-8. The lesion was removed by enucleation and curettage, while the periosteum was carefully preserved. Fixation with screw and plate was also performed. Conclusions: Correct diagnosis of COF and precise implementation of the periosteal osteogenesis technique, in this case, resulted in entirely and spontaneously bone regeneration, which was a rare and favorable outcome with minimum cost and complications for the patient.
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Background: Accurate shade matching of metal-ceramic restorations with natural teeth is one of the most challenging aspects of dental restorations and esthetic dentistry. The aim of this study was to evaluate of the color parameters of two types of porcelain systems VMK Master and VM13 porcelain with VITA 3D-master shade guide. Materials and Methods: In this in vitro study a total of 56 metal discs (10 mm diameter and 2 mm thickness) were fabricated. Each of the disks was veneered with porcelain (Vita Zahnfabrik, Bad Sackingen, Germany) of the VITA shade. The discs were randomly divided into four groups (2M2 and 3M2 from VM13, 2M2 and 3M2 from VMK master) of 14 (n = 14). The spectrophotometer was used for taking color measurements based on the numerical color data of the CIELAB color system. Data analysis was performed by t-test (P < 0.05). Results: Comparison of color parameters in different porcelain showed that the type of porcelain caused a significant difference in color parameters (L, a, and b) (P < 0.05). The degree of translucency (L*) or glaze of VMK porcelains was higher than VM13, but the parameters a* and b* were higher in VM13 porcelains than VMK (P < 0.05). Furthermore, the color difference of two porcelain in 2M2 (1.63 ± 0.84) and 3M2 (1.71 ± 0.96) shades was within the acceptable clinical limit. Considering the total color difference (ΔE), there were no significant differences between the ΔE values produced by any of shades (P > 0.05). Conclusion: In the present study, the spectrophotometric analysis revealed that the porcelain shade type causes a change in the color parameters, but the color difference between two porcelains VMK and VM13 is within the acceptable range of clinical color. Therefore, both porcelain systems with 2M2 and 3M2 shades are suitable for enhancing the results of restorative dentistry.
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PURPOSE: This study was designed to assess dosimetric characteristics of 3D-printed personalized multi-channel cylinder applicator (MCCA). MATERIAL AND METHODS: UnionTech RS Pro 600 (UnionTech, Inc., Shanghai, China) 3D printer was used for manufacturing MCCA. The geometry of MCCA was designed with Fusion 360 v.2.0.5827 (Autodesk, Inc.) software. The designed file was exported to Meshmixer v.3.5 (Autodesk, Inc.) to create three-dimensional model in stereolithography (STL) file format, which is the common file format for inputting data to 3D printers. We used high-temp resin, FLHTAM02 model (Formlabs Inc., MA, USA), as material in 3D printing process. This resin model has good resistance to high temperature and compatibility with various solvents. We created a simple cubic shape phantom for dosimetric evaluation of the applicator with Gafchromic EBT3 films. Also, Monte Carlo method was applied to simulate MCCA in the same configuration as in experimental test. RESULTS: The mean ± standard deviation (SD) difference between measured and calculated doses in treatment planning system (TPS) for all control points was 0.0860 ±0.0393 Gy, corresponding to 4.01 ±1.21%. The mean ±SD difference between doses calculated by Monte Carlo simulation and TPS for all control points was 0.0996 ±0.0471 Gy, corresponding to 4.58 ±1.05%. The mean ±SD of dose difference between film measurement and Monte Carlo simulation for all control points was 0.0136 ±0.0200 Gy, corresponding to 0.60 ±0.69%. P-value for dose difference between film measurement and TPS, Monte Carlo and TPS, and film measurement and Monte Carlo were 0.7, 0.66, and 0.95, respectively. CONCLUSIONS: Dosimetric results and mechanical accuracy of MCCA show that high-temp resin with SLA 3D printing technique can be used for producing patient-specific MCCA in brachytherapy.
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AIMS: Apigenin (4',5,7-trihydroxyflavone) is one of the subclasses of flavonoids and has various pharmacological effects. The present work was carried out to study the effect of apigenin on ethylene glycol-induced kidney damage in male Wistar rats. MAIN METHODS: We evaluated the effects of apigenin orally administrated in normal and urolithiatic rats. Animals were assigned to nine groups in random: normal control; apigenin alone (0.005, 0.01, and 0.02 g/kg bw); urolithiatic control (0.75% ethylene glycol and 1.0% ammonium chloride in drinking water); apigenin (0.005, 0.01, and 0.02 g/kg bw) plus ethylene glycol and ammonium chloride; and cystone (0.75 g/kg bw) plus ethylene glycol and ammonium chloride. At the end of 28th day of treatment, animals were sacrificed for biochemical and histopathological assays. KEY FINDINGS: Our results indicated that the apigenin treatment decreased the formation of urinary stones in urolithiatic rats. Also, apigenin reduced the generation of malondialdehyde and enhanced antioxidant enzymes activities in the kidney homogenate of rats. It also caused a significant decrease in the calcium oxalate crystals numbers in urinary sample of rats with ethylene glycol-induced hyperoxaluria. These findings were supported by histopathological examinations. SIGNIFICANCE: Based on the results obtained, apigenin attenuate ethylene glycol-related kidney damage in male Wistar rats. Although the underlying mechanism of apigenin effect has not been determined, reduction of urinary levels of stone-producing constituents, antioxidant activities, and inhibition of TGF-ß signaling may be involved.
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Apigenina/farmacología , Glicol de Etileno/toxicidad , Inflamación/prevención & control , Estrés Oxidativo/efectos de los fármacos , Sustancias Protectoras/farmacología , Urolitiasis/tratamiento farmacológico , Animales , Inflamación/etiología , Inflamación/metabolismo , Inflamación/patología , Masculino , Ratas , Ratas Wistar , Urolitiasis/inducido químicamente , Urolitiasis/metabolismo , Urolitiasis/patologíaRESUMEN
Despite all the new treatments, metastatic breast cancer (BC) causes many deaths. Chlorogenic acid (CGA) is a polyphenol compound with various pharmacological traits, such as anticancer properties. Targeting apoptotic death pathways has been propounded as the most effective therapeutic method in various cancers. In the current study, apoptotic agents such as p53, Bax, Bcl-2, and caspase-3 have been investigated. The experimental groups included saline, BC, CGA, protective (PR), and treatment (TM) groups. First, 4T1 mouse BC was established and then the effects of treatment with CGA were investigated through measurement of tumor weight and volume, metastatic nodules, liver biochemical tests, hematoxylin and eosin (H&E), immunohistochemistry (IHC) staining, and real-time reverse transcription-polymerase chain reaction (RT-PCR) in experimental groups. The findings showed that CGA reduced tumor weight and volume in the PR group (P < .05) and in the TM group (P < .001). Surprisingly, it eliminated the tumors in the TM group. Metastatic nodules in the PR and TM groups were significantly reduced as compared with the BC group (P < .001). The evaluation by H&E staining showed cell apoptosis in both the PR and TM groups. The results of real-time RT-PCR showed that CGA therapy increased the expression ratio of Bax/Bcl-2 (P < .001 and P < .05, respectively) and the expression of p53 (P < .001 and P < .05, respectively) and caspase-3 genes (P < .01) in the PR and TM groups. The IHC data regarding the Bax/Bcl-2 ratio confirmed the other results (P < .001). The findings demonstrate that CGA plays a significant role in the induction of apoptosis and the treatment of 4T1 BC tumors in BALB/c mice.
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Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Ácido Clorogénico/farmacología , Neoplasias Mamarias Experimentales/patología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Animales , Peso Corporal/efectos de los fármacos , Línea Celular Tumoral , Femenino , Pruebas de Función Hepática , Neoplasias Mamarias Experimentales/metabolismo , Ratones , Ratones Endogámicos BALB C , Metástasis de la Neoplasia , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
BACKGROUND: Gutta-percha has been the predominant root canal filling material which is developed with different taper. Canal obturation fixed with nickel-titanium (NiTi) instruments and tapered gutta-percha master cone and lateral condensation is advantageous because it is clinically effectual and appears to result in a radiographically acceptable outcome. The aim of this in vitro study was to determine the effect of tapered master gutta-percha cone on apical seal of straight and curved root canals using NiTi rotary files. MATERIALS AND METHODS: In this in vitro study total of 130 mandibular molars were selected and divided into six experimental groups (n = 20) based on the degree of root canal curvatures (0°-20°and 20°-40°) and the taper of master cones (0.02, 0.04, and 0.06). The roots were immersed in the bacterial leakage model and monitored daily for a period of 70 days. Data were analyzed using Kaplan-Meier approach, log-rank test, and Chi-square tests. P < 0.05 was considered statistically significant. RESULTS: The microleakage in the 0°-20° canal curvature using 0.02- and 0.04-tapered master cones was similar and considerably <0.06-tapered master cone (P < 0.05). However, the microleakage in the 20°-40° canal curvature using 0.02- and 0.04-tapered master cones was more than 0°-20° and for 0.06-tapered master cone was <0°-20°, but there was no statistical difference between the use of 0.02-, 0.04-, and 0.06-tapered master cones (P > 0.05). CONCLUSION: The lateral condensation filling technique using 0.02- and 0.04-tapered master cones is more effective in minimizing microbial leakage in straight canals than 0.06-tapered master cone.
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OBJECTIVE(S): Chlorogenic acid is an herbal compound with various effects such as antiviral, antioxidant, and anticancer effect with low toxicity, which inhibits cell proliferation. Clinical studies had shown that chlorogenic acid has a positive effect on the different types of cancers treatment. Hence, this study evaluates chlorogenic acid effects on 4T1 breast cancer cells. MATERIALS AND METHODS: In this study, cell proliferation was measured using an 3-(4,5-methylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay (MTT) on 4T1 cells. Afterwards, other assays like P53, Caspase-3 proteins expression and Annexin V/PI were detected by flow cytometry. Also; Bax and Bcl-2 were carried out by immunocytochemistry. RESULTS: 200 µM of chlorogenic acid concentration showed the highest level of cytotoxicity toward 4T1 cells. Percentage of cell viability data were significant in 100 µM (P < 0.05) and 150, 200 µM (P < 0.001) doses. The evaluation using Annexin V/PI showed cell apoptosis in 100 µM (P < 0.05), 150 µM (P < 0.01), and for 200 µM (P < 0.05 and P < 0.01). Immunocytochemistry results showed the upregulation of Bax and also the downregulation of Bcl-2 in 4T1 cells treated with chlorogenic acid (P < 0.001). The expression level of P53 and caspase-3 increased during treatment with chlorogenic acid in the 4T1 cells (P < 0.001). CONCLUSION: Our findings demonstrated that chlorogenic acid plays a notable role on apoptosis inducing in the 4T1 cells through regulation of apoptotic proteins.
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Neoplasias de la Mama/tratamiento farmacológico , Ácido Clorogénico/farmacología , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Caspasa 3/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ácido Clorogénico/uso terapéutico , Modelos Animales de Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ratones , Proteínas Proto-Oncogénicas c-bcl-2/genética , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Proteína p53 Supresora de Tumor/genética , Proteína X Asociada a bcl-2/genética , Proteína X Asociada a bcl-2/metabolismoRESUMEN
Mitochondria are highly dynamic organelles that can exhibit a wide range of morphologies. Mitochondrial morphology can differ significantly across cell types, reflecting different physiological needs, but can also change rapidly in response to stress or the activation of signaling pathways. Understanding both the cause and consequences of these morphological changes is critical to fully understanding how mitochondrial function contributes to both normal and pathological physiology. However, while robust and quantitative analysis of mitochondrial morphology has become increasingly accessible, there is a need for new tools to generate and analyze large data sets of mitochondrial images in high throughput. The generation of such datasets is critical to fully benefit from rapidly evolving methods in data science, such as neural networks, that have shown tremendous value in extracting novel biological insights and generating new hypotheses. Here we describe a set of three computational tools, Cell Catcher, Mito Catcher and MiA, that we have developed to extract extensive mitochondrial network data on a single-cell level from multi-cell fluorescence images. Cell Catcher automatically separates and isolates individual cells from multi-cell images; Mito Catcher uses the statistical distribution of pixel intensities across the mitochondrial network to detect and remove background noise from the cell and segment the mitochondrial network; MiA uses the binarized mitochondrial network to perform more than 100 mitochondria-level and cell-level morphometric measurements. To validate the utility of this set of tools, we generated a database of morphological features for 630 individual cells that encode 0, 1 or 2 alleles of the mitochondrial fission GTPase Drp1 and demonstrate that these mitochondrial data could be used to predict Drp1 genotype with 87% accuracy. Together, this suite of tools enables the high-throughput and automated collection of detailed and quantitative mitochondrial structural information at a single-cell level. Furthermore, the data generated with these tools, when combined with advanced data science approaches, can be used to generate novel biological insights.
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Mitocondrias/metabolismo , Programas Informáticos , Animales , Biología Computacional , Humanos , Procesamiento de Imagen Asistido por Computador , Mitocondrias/genética , Dinámicas Mitocondriales/genética , Dinámicas Mitocondriales/fisiología , Transducción de Señal/genética , Transducción de Señal/fisiologíaRESUMEN
Repeated injection of morphine during conditioned place preference (CPP) leads to spatial craving due to high-level nitric oxide (NO) in the central nucleus of amygdala (CeA). Silver nanoparticles (Ag-NPs) can produce oxygen-free radicals that lead to NO formation. We aimed to show the Ag-NPs protective effect on naloxone (NLX)-induced morphine withdrawal in the conditioned rats. Wistar rats (300-350 g) were implanted with cannulae in the CeA. After recovery, they were randomly divided into experimental and saline groups. CPP was conducted by three-phase unbiased program. Morphine (0.5-7.5 mg/kg) was injected subcutaneously (s.c.) once/per day during the conditioning phase. Naloxone (NLX) (0.05-0.4 µg/rat) was given, intra-CeA, 10 min before the CPP test. Ag-NPs (0.0001-0.01 µg/rat) were administered alone or prior to the NLX effective dose (0.4 µg/rat), intra-CeA. Conditioning score and withdrawal signs (wet dog shaking and scratching) were obtained and compared with saline group data. All rats' brains were collected in formalin 10% and after 48-72 h stained with NADPH-diaphorase, the NO marker. All data were analyzed by one-way or two-way ANOVA. Morphine (2.5-7.5 mg/kg, s.c.) induced a significant CPP vs. saline (1 mL/kg, s.c.). The single Ag-NPs had no significant effect, whereas the NLX caused meaningful WDS and scratching. However, the NLX pre-treatment in combination with Ag-NPs eliminated these signs. Furthermore, the NO level increased in the CeA. The Ag-NPs may protect the morphine-conditioned rats against the NLX-induced withdrawal symptoms due to high-level NO in the CeA.
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Analgésicos Opioides/toxicidad , Conducta Animal/efectos de los fármacos , Núcleo Amigdalino Central/efectos de los fármacos , Condicionamiento Psicológico/efectos de los fármacos , Nanopartículas del Metal , Morfina/toxicidad , Naloxona , Antagonistas de Narcóticos , Óxido Nítrico/metabolismo , Compuestos de Plata/farmacología , Síndrome de Abstinencia a Sustancias/prevención & control , Animales , Núcleo Amigdalino Central/metabolismo , Núcleo Amigdalino Central/fisiopatología , Modelos Animales de Enfermedad , Masculino , Ratas Wistar , Síndrome de Abstinencia a Sustancias/metabolismo , Síndrome de Abstinencia a Sustancias/fisiopatologíaRESUMEN
Ovarian cancer is the deadliest gynecological cancer in women, with a survival rate of less than 30% when the cancer has spread throughout the peritoneal cavity. Aggregation of cancer cells increases their viability and metastatic potential; however, there are limited studies that correlate these functional changes to specific phenotypic alterations. In this study, we investigated changes in mitochondrial morphology and dynamics during malignant transition using our MOSE cell model for progressive serous ovarian cancer. Mitochondrial morphology was changed with increasing malignancy from a filamentous network to single, enlarged organelles due to an imbalance of mitochondrial dynamic proteins (fusion: MFN1/OPA1, fission: DRP1/FIS1). These phenotypic alterations aided the adaptation to hypoxia through the promotion of autophagy and were accompanied by changes in the mitochondrial ultrastructure, mitochondrial membrane potential, and the regulation of reactive oxygen species (ROS) levels. The tumor-initiating cells increased mitochondrial fragmentation after aggregation and exposure to hypoxia that correlated well with our previously observed reduced growth and respiration in spheroids, suggesting that these alterations promote viability in non-permissive conditions. Our identification of such mitochondrial phenotypic changes in malignancy provides a model in which to identify targets for interventions aimed at suppressing metastases.
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Healthy mitochondria use an electrochemical gradient across the inner mitochondrial membrane (IMM) to generate energy in the form of ATP. A variety of endogenous and exogenous factors can lead to transient or sustained depolarization of the IMM, including mitochondrial fission events, expression of uncoupling proteins, electron transport chain (ETC) inhibitors, or chemical uncouplers. This depolarization in turn leads to a variety of physiological responses, ranging from selective mitochondrial clearance (mitophagy) to cell death. How cells recognize and ultimately respond to depolarized mitochondria remains incompletely understood. Here we show that the small GTPases RalA and RalB both relocalize to mitochondria following depolarization in a process dependent on clathrin-mediated endocytosis (CME). Furthermore, both genetic and pharmacologic inhibition of RalA and RalB leads to an increase in the activity of the atypical IκB kinase TBK1 both basally and in response to mitochondrial depolarization. This phenotype was also observed following inhibition of Ral relocalization. Collectively, these data suggest a model in which RalA and RalB inhibit TBK1 and that relocalization of Ral to depolarized mitochondria facilitates TBK1 activation through release of this inhibition.
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Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas de Unión al GTP ral/metabolismo , Carbonil Cianuro m-Clorofenil Hidrazona/farmacología , Clatrina/metabolismo , Endocitosis , Células HeLa , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Modelos Biológicos , Transporte de Proteínas , ARN Interferente Pequeño/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas de Unión al GTP ral/antagonistas & inhibidores , Proteínas de Unión al GTP ral/genéticaRESUMEN
BACKGROUND: Transcranial direct current stimulation (tDCS) is a non-invasive method that improves learning and memory. In this study, the effect of tDCS on streptozotocin (STZ) induced amnesia in the presence or absence of SCH23390 (D1 dopamine receptor antagonist) and sulpiride (dopamine D2 receptor antagonist) has been investigated in male Wistar rats. METHODS: Passive avoidance memory, locomotor activity and pain perception have been assessed by step-through, open-field and hot-plate instruments, respectively. Anodal and cathodal tDCS were exerted on the left frontal cortex with an intensity of 0.2 milliamps for 20 minutes twice a day in 2 successive days. RESULTS: Our study showed that STZ at doses of 30 and 60 mg/ml/kg caused amnesia, while they did not alter locomotor activity and a higher dose of STZ induced analgesia 14 days after injection. SCH23390 (0.001 mg/mL/kg) and sulpiride (0.1 mg/mL/kg) did not alter memory formation by themselves and amnesia induced by STZ (30 and 60 mg/mL/kg), while SCH23390 restored the analgesia induced by STZ (60 mg/mL/kg). Moreover, left frontal anodal and cathodal tDCS restored memory impairment induced by STZ (30 and 60 mg/mL/kg). Also, SCH23390 and sulpiride could prohibit the anodic stimulating effect on memory impairment induced by a dose of 60 mg/ml/kg, but they did not hinder the effect of the cathodal stimulation on this phenomenon. CONCLUSION: The study showed that D1 and D2 dopamine receptors are involved in the restoration effect of left frontal anodal- but not cathodal-tDCS in STZ-induced amnesia.
Asunto(s)
Memoria/efectos de los fármacos , Receptores de Dopamina D1 , Receptores de Dopamina D2 , Estimulación Transcraneal de Corriente Directa/métodos , Amnesia/inducido químicamente , Animales , Antagonistas de Dopamina , Humanos , Masculino , Ratas , Ratas Wistar , Receptores Dopaminérgicos , Estreptozocina/administración & dosificaciónRESUMEN
BACKGROUND: The degree of tooth enamel wear is an important aspect of the clinical acceptability of all-ceramic restorations. The purpose of this study was to compare the degree of enamel wear by feldspathic porcelain and polymer-infiltrated ceramic. MATERIALS AND METHODS: In this in vitro study, 10 polymer-infiltrated ceramics were prepared by creating the sections of Vita Enamic® blocks (18 mm × 14 mm × 4 mm). A total of 10 porcelain cylinders were built, and feldspathic porcelain (VMK 95, Vita) was used and fired over the metal discs. A total of 20 human maxillary premolars were assigned as antagonist. Then, 10 teeth were arranged and placed oppose to porcelain samples and 10 others were placed oppose to polymer-infiltrated-ceramic specimens in the chewing simulator. The samples were photographed before and after the chewing simulation. The difference between the two photograph was measured by stereomicroscope and Motic Image plus software 2.0 three times, and then, the mean of these three times was recorded as the amount of wear. Data were analyzed using independent samples t-test and SPSS version 16. The level of significancy was 0.05. RESULTS: The mean wear rate teeth oppose to the feldspathic porcelain group (377.294 µ) was significantly higher than that of the polymer-infiltrated ceramic group (101.755 µ) (P = 0.002). CONCLUSION: In the present study, the amount of enamel wear of the natural teeth opposed to polymer-infiltrated ceramic was significantly lower than feldspathic porcelain.
RESUMEN
Alzheimer's disease (AD) is a neurodegenerative disorder and neuropathologically characterized by the aggregation of amyloid-beta (Aß) plaques, neurofibrillary tangles, enhanced oxidative stress and neurodegeneration. Involvement of serotonergic systems in AD has been supposed and it is suggested that serotonin receptors modulation may provide a novel therapeutic target for AD. This study aimed at investigating the protective effect of NAD-299 (the selective 5-HT1A receptor antagonist) and TCB-2 (the potent5-HT2A receptor agonist) on the hippocampal oxidative stress biomarkers and the number of intact neurons in streptozotocin (STZ)-induced Alzheimer's disease in rats. Fifty adult male Wistar rats weighing 250-300 g were divided into five groups: sham, STZ-treated, STZ + NAD-299 (5 µg/1 µl icv), STZ + TCB-2 (5 µg/1 µl icv) and STZ + NAD-299 (5 µg/0.5 µl icv) +TCB-2 (5 µg/0.5 µl icv). At the end of the study, the rats were weighed, then hippocampal oxidative stress markers [total antioxidant capacity (TAC), malondialdehyde (MDA), the total thiol group (TTG), and DNA damage] were measured. In addition, the number of intact neurons in the CA1 area of the hippocampus was determined using hematoxylin and eosin staining. The results showed that icv injection of STZ reduced hippocampal TAC, TTG levels and intact pyramidal cells and increased DNA damage and MDA levels in the hippocampus of STZ-treated rats. Icv administration of NAD-299, TCB-2, and NAD-299+TCB-2 increased TAC and TTG contents and hippocampal intact neurons and reduced hippocampal DNA damage, MDA levels in icv-STZ treated rats. Moreover, there was no significant difference in weight changes among the experimental groups. According to the obtained results, it is suggested that 5-HT1A receptor antagonist (NAD-299) and 5-HT2A receptor agonist (TCB-2) can reduce oxidative stress and neuronal loss in a rat model of AD and may prevent the AD progression.