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Mammalian interspecific hybrids provide unique advantages for mechanistic studies of speciation, gene expression regulation, and X chromosome inactivation (XCI) but are constrained by their limited natural resources. Previous artificially generated mammalian interspecific hybrid cells are usually tetraploids with unstable genomes and limited developmental abilities. Here, we report the generation of mouse-rat allodiploid embryonic stem cells (AdESCs) by fusing haploid ESCs of the two species. The AdESCs have a stable allodiploid genome and are capable of differentiating into all three germ layers and early-stage germ cells. Both the mouse and rat alleles have comparable contributions to the expression of most genes. We have proven AdESCs as a powerful tool to study the mechanisms regulating X chromosome inactivation and to identify X inactivation-escaping genes, as well as to efficiently identify genes regulating phenotypic differences between species. A similar method could be used to create hybrid AdESCs of other distantly related species.
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Fusão Celular/métodos , Quimera/genética , Células-Tronco Embrionárias/citologia , Células Híbridas , Camundongos , Ratos , Animais , Diferenciação Celular , Corpos Embrioides , Células-Tronco Embrionárias/metabolismo , Feminino , Haploidia , Masculino , Camundongos Endogâmicos , Ratos Endogâmicos F344 , Especificidade da Espécie , Inativação do Cromossomo XRESUMO
Phosphate solubilizing fungi Penicillium oxalicum (POX) and Red yeast Rhodotorula mucilaginosa (Rho) have been applied in Pb remediation with the combination of fluorapatite (FAp), respectively. The secretion of oxalic acid by POX and the production of extracellular polymers (EPS) by Rho dominate the Pb remediation. In this study, the potential of Pb remediation by the fungal combined system (POX and Rho) with FAp was investigated. After six days of incubation, the combination of POX and Rho showed the highest Pb remove ratio (99.7%) and the lowest TCLP-Pb concentration (2.9 mg/L). The EPS combined with POX also enhanced Pb remediation, which has a 99.3% Pb removal ratio and 5.5 mg/L TCLP-Pb concentration. Meanwhile, Rho and EPS can also stimulate POX to secrete more oxalic acid, which reached 1510.1 and 1450.6 mg/L in six days, respectively. The secreted oxalic acid can promote FAp dissolution and the formation of lead oxalate and pyromorphite. Meanwhile, the EPS produced by Rho can combine with Pb to form EPS-Pb. In the combined system of POX + Rho and POX + EPS, all of the lead oxalate, pyromorphite, and EPS-Pb were observed. Our findings suggest that the combined application of POX and Rho with FAp is an effective approach for enhancing Pb remediation.
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Apatitas , Produtos Biológicos , Minerais , Penicillium , Chumbo , Fosfatos , Ácido OxálicoRESUMO
Dickkopf-1 (DKK-1) may be involved in inflammatory response and secondary brain injury after acute brain injury. We gauged serum DKK-1 levels and further assessed its correlation with disease severity and investigated its predictive value for 90-day prognosis in patients with spontaneous intracerebral hemorrhage (sICH). Serum DKK-1 levels were measured in 128 sICH patients and 128 healthy controls. The severity of sICH was assessed using the Glasgow Coma Scale (GCS) scores and hematoma volumes. Poor prognosis was referred to as a Glasgow Outcome Scale (GOS) score of 1-3 at 90 days after stroke. Multivariate analysis was performed to identify associations of serum DKK-1 levels with disease severity, early neurological deterioration (END) and poor prognosis. Receiver operating characteristic curve (ROC) was built to investigate the prognostic predictive capability. The serum DKK-1 levels of patients were significantly higher than those of controls (median, 4.74 ng/mL versus 1.98 ng/mL; P < 0.001), and were independently correlated with hematoma volumes (ρ = 0.567, P < 0.001; t = 3.444, P = 0.001) and GCS score (ρ = -0.612, P < 0.001; t = -2.048, P = 0.043). Serum DKK-1 significantly differentiated patients at risk of END (area under ROC curve (AUC), 0.850; 95% confidence interval (CI), 0.777-0.907; P < 0.001) and poor prognosis (AUC, 0.830; 95% CI, 0.753-0.890; P < 0.001), which had similar prognostic ability, as compared to GCS scores and hematoma volumes. Subsequent Logistic regression model affirmed that GCS score, hematoma volume, and serum DKK-1 levels were independently associated with END and poor prognosis at 90 days after sICH. The models, which contained them, performed well using ROC curve analysis and calibration curve analysis. Serum DKK-1 levels are markedly associated with disease severity, END and 90-day poor prognosis in sICH. Hence, serum DKK-1 is presumed to be used as a potential prognostic biomarker of sICH.
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Hemorragia Cerebral , Peptídeos e Proteínas de Sinalização Intercelular , Humanos , Hemorragia Cerebral/sangue , Hemorragia Cerebral/diagnóstico , Masculino , Feminino , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Pessoa de Meia-Idade , Prognóstico , Idoso , Estudos Prospectivos , Escala de Coma de Glasgow , Índice de Gravidade de Doença , Curva ROC , Biomarcadores/sangue , Adulto , Estudos de Coortes , Idoso de 80 Anos ou maisRESUMO
Receptor-interacting protein kinase-3 (RIP-3) is a key component for inducing necroptosis following acute brain injury. Purpose of this study is to unveil whether serum RIP-3 levels are related to severity and clinical outcomes after human severe traumatic brain injury (sTBI). In this two-center prospective cohort study, serum RIP-3 levels were detected in 127 healthy controls coupled with 127 sTBI patients. The prognostic indicators encompassed posttraumatic 180-day mortality, overall survival and poor prognosis (defined as extended Glasgow outcome scale scores of 1-4). The prognosis associations were verified via multivariate analysis. There was a significant incremental serum RIP-3 levels in patients with sTBI, relative to the controls. RIP-3 levels of patients were independently correlated with Rotterdam Computed Tomography (CT) scores and Glasgow coma scale (GCS) scores, as well as were independently predictive of mortality, overall survival and poor prognosis. Mortality and poor prognosis were effectively predicted by serum RIP-3 levels under the receiver operating characteristic curve. Linear relationships between RIP-3 levels and their risks were verified. Mortality and poor prognosis models of serum RIP-3 levels combined with GCS and Rotterdam CT scores displayed efficient predictive abilities. The two models were graphically represented, which were of clinical stability and value by employing the calibration and decision curves. Increased serum RIP-3 levels after sTBI are closely linked to heightened trauma severity and poor prognosis, signifying that serum RIP-3 may be an encouraging biomarker for evaluating severity and predicting clinical outcome of sTBI.
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Biomarcadores , Lesões Encefálicas Traumáticas , Proteína Serina-Treonina Quinases de Interação com Receptores , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Prognóstico , Adulto , Lesões Encefálicas Traumáticas/sangue , Lesões Encefálicas Traumáticas/mortalidade , Lesões Encefálicas Traumáticas/diagnóstico , Biomarcadores/sangue , Estudos Prospectivos , Proteína Serina-Treonina Quinases de Interação com Receptores/sangue , Idoso , Escala de Coma de Glasgow , Estudos de Coortes , Adulto JovemRESUMO
Curcumin, a kind of natural compound, has been previously proven to inhibit the autophagy in hepatic stellate cells (HSCs) and induce their apoptosis. However, it is not clear whether the enhanced apoptosis of activated HSCs (aHSCs) caused by curcumin depends on autophagy inhibition. We aim to verify this hypothesis and explore the potential mechanisms in this study. Immortalized human HSC line LX-2 was used as an experimental specimen and pretreated with transforming growth factor ß1(TGF-ß1) for 24 h to activate it before drug application. The levels of autophagy, apoptosis, cell activity, lipid metabolism, and the activity of the PI3K/Akt/mTOR signal pathway were evaluated by multiple methods, such as Western blotting, mcherry-EGFP-LC3B adenoviruses transfection, immunofluorescence, Nile Red staining, flow cytometry among others. Our results showed that rapamycin, an autophagy activator, could partly offset the effects of curcumin on autophagy and apoptosis of LX-2 cells, while 3-Methyladenine (3-MA), an autophagy inhibitor, could enhance these effects. Furthermore, curcumin could promote the activity of the PI3K/Akt/mTOR signal pathway in LX-2 cells, while PI3K inhibitor could partly offset this effect and increase the autophagy level. Overall, we demonstrated that curcumin could inhibit the activity and promote LX-2 cells apoptosis by suppressing autophagy by activating the PI3K/Akt/mTOR signal pathway. In addition, lipid recovery and energy deprivation due to autophagy inhibition may be the exact mechanism by which curcumin attenuates the pro-fibrotic activity of LX-2.
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Curcumina , Células Estreladas do Fígado , Humanos , Células Estreladas do Fígado/metabolismo , Curcumina/farmacologia , Curcumina/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Apoptose , Serina-Treonina Quinases TOR/metabolismo , Autofagia , Cirrose Hepática/metabolismoRESUMO
Helicobacter pylori (H. pylori) is a well-known pathogen that infects approximately half of the world's population. It is a pathogenic agent with potential health hazards related to diverse diseases, especially digestive diseases, such as chronic gastritis, peptic ulcer, and gastric carcinoma. In clinical, antibiotics are commonly applied in eradication therapy of H. pylori. However, the increase in antibiotic resistance and side effects has induced the failure of eradication therapy. Recent studies have shown that probiotic supplementation has promising application prospects. It can restore the gastrointestinal microbiota balance and prevent dysbacteriosis caused by antibiotics. Furthermore, it has been reported to have direct or indirect inhibitory effects on H. pylori. Probiotics may have a beneficial effect on H. pylori eradication. However, the strain, dosages, duration times, and safety of probiotic supplementation need further study before clinical applications.
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Microbioma Gastrointestinal , Infecções por Helicobacter , Helicobacter pylori , Probióticos , Humanos , Infecções por Helicobacter/tratamento farmacológico , Probióticos/uso terapêutico , Antibacterianos/efeitos adversosRESUMO
Phosphates are the dominant phosphorus (P) source on Earth. The phosphates govern available P in soil, or even the complete ecosystem. The common deficiency of available P in carbonate-enriched soils suggests the tight correlation between P and C biogeochemistry, although the two elements have diverse abundance in soil. The influences of carbonates on P cycle were reviewed in this study, via both abiotic and biotic pathways. The abiotic processes at geochemical scale include element release, transport, sorption, desorption, weathering, precipitation, etc. The sorption of P on carbonate and buffering ability of carbonates were particularly addressed. Biotic factors are ascribed to various microorganisms in soil. As the most active P pool in soil, microorganisms prefer to consume abundant P, and then accumulate it in their biomass. Carbonates, however, are usually utilized by microorganisms after conversion to organic C. Meanwhile, extracellular precipitation of Ca-P phases significantly regulates the transportation of P in/out the cells. Moreover, they boost and complexify both carbonates and P turnover in soil via bioweathering and biomineralization, i.e., the intense interactions between biosphere and lithosphere. Based on this review, we proposed that carbonates may negatively affect P supply in soil system. This comprehensive review regarding the regulation by carbonates on P biogeochemistry would shed a light on predicting long-term P availability influenced by C biogeochemistry.
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Fósforo , Solo , Carbonatos , Ecossistema , Fosfatos , Solo/químicaRESUMO
Polysulfide shuttling and sluggish sulfur redox kinetics hinder the cyclability and rate capability of lithium-sulfur (Li-S) batteries. The intrinsic redox kinetics of sulfur cathodes strongly depends on the interaction between catalysts and sulfur species. Herein, N-doped CoTe2 is proposed as an effective dual-anchoring electrocatalyst, which can simultaneously bind Li and S atoms in lithium polysulfides via ionic Te-Li/N-Li bonding and coordinate covalent Co-S bonding. The incorporated N not only serves as enhanced lithiophilic site, but also an agent to improve the sulfiphilicity of the Co site as revealed by a series of experimental and computational results. Benefiting from these superiorities, the use of N-doped CoTe2 as a catalytic interlayer enables efficient operation of Li-S batteries in terms of impressive rate capability of 758 mAh g-1 at 4 C and very low capacity decay of 0.021% per cycle over 1000 cycles. The material and strategy demonstrated in this work may open the door toward developing more advanced Li-S electrocatalysts.
RESUMO
Mesoporous silica is widely used because of its unique and excellent properties, especially it can be used as a drug carrier and gene carrier in the biomedical field. After the mesoporous silica is put into clinical use, it is more likely to be exposed in human body. Therefore, the effect of mesoporous silica on human body cannot be ignored. The injury of vascular endothelial cells is a prerequisite for the occurrence of many cardiovascular diseases. As a drug and gene carrier, mesoporous silica increases its contact with vascular endothelial cells, so its toxic effect on cardiovascular system cannot be ignored. In this study, amino (NH2 ) and carboxyl (COOH) were modified on mesoporous silica SBA-15 by post-grafting. The results showed that it still maintained the one-dimensional hexagonal mesoporous structure of SBA-15 and had typical mesoporous structure. Then human umbilical vein endothelial cells (HUVECs) were infected with SBA-15, NH2 -SBA-15, and COOH-SBA-15. The results showed that the functionalized mesoporous silica SBA-15 had cytotoxicity to HUVECs and damaged the cell membrane, but compared with the unmodified mesoporous silica SBA-15 the cytotoxicity of functionalized mesoporous silica SBA-15 was lower and the toxicity of carboxyl modified group was the lowest. By comparing the cell inhibition rate and the expression level of lactate dehydrogenate and reactive oxygen species induced by the three materials, oxidative damage and cell membrane damage may be two mechanisms of cytotoxicity. Mesoporous silica SBA-15 has an effect on cardiovascular system by inducing the high expression of nitric oxide, intercellular adhesive molecule-1 and vascular cell adhesive molecule-1 in HUVECs. In summary, our results show that mesoporous silica is toxic to vascular endothelial cells.
Assuntos
Portadores de Fármacos , Dióxido de Silício , Células Endoteliais da Veia Umbilical Humana , Humanos , Dióxido de Silício/toxicidadeRESUMO
PURPOSE: Clinical research suggests that transcranial direct current stimulation (tDCS) at bilateral supraorbital foramen and inferior orbital rim and nose intersections may facilitate rehabilitation after stroke. However, the underlying neurobiological mechanisms of tDCS remain poorly understood, impeding its clinical application. Here, we investigated the effect of tDCS applied after stroke on neural cells. MATERIALS AND METHODS: Middle cerebral arterial occlusion (MCAO) reperfusion was induced in rats. Animals with comparable infarcts were randomly divided into MCAO group and MCAO + tDCS group. Recovery of neurological function was assessed behaviorally by modified neurological severity score (mNSS). Ischemic tissue damage verified histologically by TTC and HE staining. Immunohistochemical staining, real-time qPCR, and western blot were applied to determine the changes of neural cells in ischemic brains. RESULTS: The results reveal that tDCS treated by multilead brain reflex instrument can promote the recovery of neurological function, remarkably reduce cerebral infarct volume, promote brain tissue rehabilitation, and can effectively inhibit astrocytosis and enhance neuronal survival and synaptic function in ischemic brains. CONCULSIONS: Our study suggests that tDCS treated by multilead brain reflex instrument could be prospectively developed into a clinical treatment modality.
Assuntos
Gliose/terapia , Infarto da Artéria Cerebral Média/reabilitação , AVC Isquêmico/reabilitação , Neurônios , Recuperação de Função Fisiológica , Reabilitação do Acidente Vascular Cerebral , Estimulação Transcraniana por Corrente Contínua , Animais , Sobrevivência Celular/fisiologia , Modelos Animais de Doenças , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/fisiopatologia , AVC Isquêmico/etiologia , AVC Isquêmico/patologia , AVC Isquêmico/fisiopatologia , Masculino , Neurônios/metabolismo , Neurônios/patologia , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/fisiologia , Índice de Gravidade de DoençaRESUMO
Successful application of microorganisms to heavy metal remediation depends on their resistance to toxic metals. This study contrasted the differences of tolerant mechanisms between Pb2+ and Cd2+ in Enterobacter sp. Microbial respiration and production of formic acid showed that Enterobacter sp. had a higher tolerant concentration of Pb (>1000 mg l-1 ) than Cd (about 200 mg l-1 ). Additionally, SEM confirmed that most of Pb and Cd nanoparticles (NPs) were adsorbed onto cell membrane. The Cd stress, even at low concentration (50 mg l-1 ), significantly enlarged the sizes of cells. The cellular size raised from 0.4 × 1.0 to 0.9 × 1.6 µm on average, inducing a platelet-like shape. In contrast, Pb cations did not stimulate such enlargement even up to 1000 mg l-1 . Moreover, Cd NPs were adsorbed homogeneously by almost all the bacterial cells under TEM. However, only a few cells work as 'hot spots' on the sorption of Pb NPs. The heterogeneous sorption might result from a 'self-sacrifice' mechanism, i.e., some cells at a special life stage contributed mostly to Pb sorption. This mechanism, together with the lower mobility of Pb cations, caused higher microbial tolerance and removal efficiency towards Pb2+ . This study sheds evident contrasts of bacterial resistance to the two most common heavy metals.
Assuntos
Cádmio/toxicidade , Enterobacter/efeitos dos fármacos , Chumbo/toxicidade , Nanopartículas Metálicas/toxicidade , Adsorção , Cádmio/química , Membrana Celular/química , Tamanho Celular/efeitos dos fármacos , Enterobacter/química , Enterobacter/metabolismo , Enterobacter/ultraestrutura , Formiatos/metabolismo , Chumbo/química , Nanopartículas Metálicas/química , Microscopia Eletrônica de Transmissão , Estresse FisiológicoRESUMO
Flexible asymmetric supercapacitors are more appealing in flexible electronics because of high power density, wide cell voltage, and higher energy density than symmetric supercapacitors in aqueous electrolyte. In virtues of excellent conductivity, rich porous structure and interconnected honeycomb structure, three dimensional graphene aerogels show great potential as electrode in asymmetric supercapacitors. However, graphene aerogels are rarely used in flexible asymmetric supercapacitors because of easily re-stacking of graphene sheets, resulting in low electrochemical activity. Herein, flower-like hierarchical Mn3 O4 and carbon nanohorns are incorporated into three dimensional graphene aerogels to restrain the stack of graphene sheets, and are applied as the positive and negative electrode for asymmetric supercapacitors devices, respectively. Besides, a strong chemical coupling between Mn3 O4 and graphene via the C-O-Mn linkage is constructed and can provide a good electron-transport pathway during cycles. Consequently, the asymmetric supercapacitor device shows high rate cycle stability (87.8 % after 5000â cycles) and achieves a high energy density of 17.4â µWh cm-2 with power density of 14.1â mW cm-2 (156.7â mW cm-3 ) at 1.4â V.
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Pluripotency of embryonic stem cells (ESCs) can be functionally assessed according to the developmental potency. Tetraploid complementation, through which an entire organism is produced from the pluripotent donor cells, is taken as the most stringent test for pluripotency. It remains unclear whether ESCs of other species besides mice can pass this test. Here we show that the rat ESCs derived under 2i (two small molecule inhibitors) conditions at very early passages are able to produce fertile offspring by tetraploid complementation. However, they lose this capacity rapidly during culture due to a nearly complete loss of genomic imprinting. Our findings support that the naïve ground state pluripotency can be captured in rat ESCs but also point to the species-specific differences in its regulation and maintenance, which have implications for the derivation and application of naïve pluripotent stem cells in other species including human.
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Embrião de Mamíferos/citologia , Desenvolvimento Embrionário/fisiologia , Células-Tronco Embrionárias/citologia , Células-Tronco Pluripotentes/citologia , Animais , Diferenciação Celular , Células Cultivadas , Feminino , Teste de Complementação Genética , Camundongos , Ratos , Ratos Endogâmicos F344 , TetraploidiaRESUMO
Neddylation has been researched in many different human carcinomas. However, the roles of neural precursor cell expressed, developmentally downregulated 8 (NEDD8) in bladder cancer are still unknown. Our study was the first study which systematically investigated the possible functions of NEDD8 in bladder cancer (BC) progression. We carried out immunohistochemistry to explore associations between the expression of NEDD8 in tumor tissues and clinical outcomes of patients. RT-qPCR and western blot were used to detect the expressional levels of genes. The biological abilities of cell proliferation, migration and invasion were researched by in vitro and in vivo experiments. Results were as follows: Data from The Cancer Genome Atlas (TCGA) database showed that NEDD8 was overexpressed in BC tissues and was associated with poor patient survival. Results of immunohistochemistry found that NEDD8 was significantly associated with poor clinical outcomes of BC patients. Suppression of NEDD8 could inhibit the proliferation, migration and invasion of tumor cells. Knocking down NEDD8 could induce apoptosis and G2 phase arrest of cell cycle progression. In vivo, suppression of NEDD8 restricted growth and metastasis of tumors in mice. In conclusion, NEDD8 has important roles in regulating the progression of BC cells and was associated with poor prognosis of patients; hence, it may become a potential therapeutic target of BC.
Assuntos
Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Proteína NEDD8/genética , Neoplasias da Bexiga Urinária/genética , Animais , Linhagem Celular Tumoral , Progressão da Doença , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteína NEDD8/metabolismo , Invasividade Neoplásica , Prognóstico , Interferência de RNA , Terapêutica com RNAi/métodos , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/terapia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Environmental microorganisms have been widely applied in heavy metal remediation. This study explored the mechanisms of lead tolerance of two typical filamentous fungi, Aspergillus niger and Penicillium oxalicum. It is shown that the mechanisms of reducing Pb toxicity by these two fungi have three major pathways. The secreted oxalic acid can react with Pb (II) to form insoluble Pb minerals, primarily lead oxalate. Then, the enhanced biosorption via forming new border of cell wall prevents the transportation of Pb (II) into hypha. In addition, the fungal activity could be maintained even at high Pb concentration due to the intracellular accumulation. It was confirmed that A. niger has the higher Pb tolerance (up to 1500 mg l-1 Pb level) compared with P. oxalicum (up to 1000 mg l-1 ). Meanwhile, Pb levels below 1000 mg l-1 partially stimulate the bioactivity of A. niger, which was confirmed by its elevated respiration (from 53 to 63 mg C l-1 medium h-1 ). This subsequently enhanced microbial functions of A. niger to resist Pb toxicity. A better understanding of Pb tolerance of these two fungi sheds a bright future of applying them to remediate lead-contaminated environments.
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Aspergillus niger/metabolismo , Biodegradação Ambiental , Chumbo/toxicidade , Ácido Oxálico/metabolismo , Penicillium/metabolismo , Aspergillus niger/efeitos dos fármacos , Minerais/metabolismo , Oxalatos/metabolismo , Penicillium/efeitos dos fármacosRESUMO
BACKGROUND: Bladder cancer is the most common malignancy of urinary system with high morbidity and mortality. In general, the development and progression of bladder cancer are complicated pathological processes, and the treatment methods mainly include surgical resection, radiotherapy, chemotherapy, and combined therapy. In recent years, targeted therapy has made progress in the treatment of bladder cancer. Therefore, to improve survival rates of patients with advanced bladder cancer, novel therapeutic targets are still urgently needed. METHODS AND RESULTS: In this study, we found that RAB38 expressed in tumor tissues of patients with bladder cancer was linked to clinical features including pTNM stage and tumor recurrence, and positively correlated with the poor prognosis of bladder cancer. Notably, further results indicated that depletion of RAB38 could significantly inhibit the proliferation and motility of two types of human bladder cancer cells, T24 and 5637 cells. In addition, RAB38 ablation obviously blocked tumor growth and development in mice compared with control. CONCLUSION: In conclusion, this study provides significant evidence that RAB38 promotes the development of bladder cancer and provides a novel therapeutic target of bladder cancer.
Assuntos
Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Neoplasias da Bexiga Urinária/patologia , Proteínas rab de Ligação ao GTP/fisiologia , Animais , Humanos , Camundongos , Células Tumorais CultivadasRESUMO
Mineral particles in bone are interlaced with collagen fibrils, hindering the investigation of bioapatite crystallites (BAp). This study utilized a special whale rostrum (the most highly mineralized bone ever recorded) to measure the crystallites of bone BAp via long-term dissolution in water. The BAp in the rostrum has a low solubility (6.7 ppm Ca and 3.8 ppm P after 150 days dissolution) as well as in normal bones, which leads to its Ksp value of ~10-53. Atomic force microscopy results show tightly compacted mineral crystallites and confirm the low amount of collagen in the rostrum. Additionally, the mineral crystallites demonstrate irregular plate-like shapes with variable sizes. The small crystallites (~11 × 24 nm) are easily detached from BAp prisms, compared with the large crystallites (~50 nm). Moreover, various orientations of crystallites are observed on the edge of the prisms, which suggest a random direction of mineral growth. Furthermore, these plate-like crystallites prefer to be stacked layer by layer under weak regulation from collagen. The morphology of rostrum after dissolution provides new insights into the actual morphology of BAp crystallites.
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Apatitas/metabolismo , Osso e Ossos/química , Osso e Ossos/ultraestrutura , Colágeno/ultraestrutura , Cristalização , Baleias , Animais , Colágeno/análise , Microscopia de Força AtômicaRESUMO
The effects of thermoplastic polyimide (PI) and polypropylene (PP) fibers and areal density of toughened layer on interlaminar fracture toughness and impact performance of carbon fiber/epoxy (CF/EP) laminated composites were studied. Mode I interlaminar fracture toughness (GIC) was analyzed via double cantilever beam (DCB) tests. When comparing for the toughener type, PI played a positive role in enhancing the mode-I fracture toughness, while PP was not effective due to the less fiber bridge formed during composite curing. The toughening effects of areal density of PI were further investigated by end notched flexure (ENF) testing and low velocity impact testing to better understand the toughening mechanisms. The results revealed that the toughening effect reached its best effectiveness when the areal density of toughened layer was 30 g/m2. Compared with the control group, GIC and GIIC of CF/EP laminated composite were increased by 98.49% and 84.07%, and Fmax and Ee were enhanced by 92.38% and 299.08% under low velocity impact. There is no obvious delamination phenomenon on the surface of laminates after low velocity impact, indicating the improved interlaminar and impact performance of laminated composite.
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Fibra de Carbono/química , Resinas Epóxi/química , Fibra de Carbono/ultraestrutura , Teste de Materiais , Fenômenos MecânicosRESUMO
BACKGROUND/AIMS: Spinal microglia and astrocytes are the main responders to the inflammatory cascade and process pain through various neural interactions. CXCL10 is a late-phase protein that accelerates arteriogenesis during reperfusion through CXCR3. However, the early-phase expression (within 72 h postoperatively) of CXCL10 and CXCR3 during the development of ischemia-reperfusion (IR)-induced inflammatory pain remains unclear. We investigated whether this chemokine pair participates in glial interactions during early-phase IR injury. METHODS: A rat model was induced by an 8-min occlusion of the aortic arch. Temporal assessments of mechanical and thermal allodynia and the protein levels of CXCL10 and CXCR3 were determined through measurements of paw withdrawal thresholds (PWTs) and paw withdrawal latencies (PWLs) and Western blotting assays. The co-localization of various cells with glial cells was detected by double immunofluorescence. The effects of CXCL10/CXCR3 on glial interactions were explored by intrathecal treatment with specific inhibitors (AMD487, minocycline and fluorocitrate) and recombinant CXCL10, and subsequent release of cytokines was assessed by ELISAs. RESULTS: The IR injury initiated bimodal allodynia within 72 h of reperfusion, as illustrated by two W-shape trends in the PWTs and PWLs with two minima at 12 and 48 h post-IR. Allodynia was highly correlated with overexpression of CXCL10 and CXCR3, which were expressed in microglia at the early stage and in both microglia and astrocytes at the late stage, as shown by increased CXCL10 and CXCR3 immunoreactivities and double-labeled cells. AMD487 and minocycline injections exerted comparable inhibitory effects on CXCR3 and Iba-1 and on GFAP immunoreactivity at 12 and 48 h post-IR, and these inhibitory effects were only observed at 48 h following fluorocitrate injection. The levels of TNF-α and IL-6 showed variations in concert with the changes in Iba-1 and GFAP immunoreactivities. Recombinant CXCL10 injection reversed the abovementioned effects. CONCLUSION: The results showed that CXCL10/CXCR3 are involved in bimodal inflammatory pain during early-phase IR injury. The sequential activation of and crosstalk between microglia and astrocytes mediated through CXCR3 upregulation suggested that treatments targeting specific cell types are important in post-IR allodynia.
Assuntos
Quimiocina CXCL10/metabolismo , Hiperalgesia/etiologia , Receptores CXCR3/metabolismo , Traumatismo por Reperfusão/patologia , Animais , Astrócitos/citologia , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Modelos Animais de Doenças , Proteína Glial Fibrilar Ácida/metabolismo , Proteínas dos Microfilamentos/metabolismo , Microglia/citologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Minociclina/farmacologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/complicações , Medula Espinal/metabolismo , Medula Espinal/patologiaRESUMO
BACKGROUND The aim of this study was to detect the expression of fork-head box D3 (FOXD3) and investigate its diagnostic value in patients with non-small cell lung cancer (NSCLC). MATERIAL AND METHODS The relative expression of FOXD3 at mRNA and protein levels was determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blotting analysis, respectively. Chi-square test was used to explore the relevance of FOXD3 expression with clinical features of NSCLC patients. A receiver operating characteristic (ROC) curve was built to estimate the diagnostic value of FOXD3 in distinguishing NSCLC patients from healthy controls. RESULTS Serum FOXD3 expression was weakly expressed in NSCLC patients compared to the controls at mRNA and protein levels (P<0.001) and low FOXD3 expression was positively correlated with TNM stage, lymph node metastasis, and differentiation. The ROC curve indicated that FOXD3 acts as a diagnostic bio-marker for NSCLC patients, with an AUC of 0.826 corresponding to a sensitivity of 77.1% and a specificity of 74.6%, and an optimal cutoff point of 2.38. CONCLUSIONS Decreased expression of serum FOXD3 was observed in NSCLC patients, and it was found to be a potential molecular marker for the diagnosis of NSCLC.