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1.
PLoS Pathog ; 19(9): e1011623, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37703276

RESUMO

The worldwide prevalence of asthma and allergic disorders (allergic rhinitis, atopic dermatitis, food allergy) has been steadily rising in recent decades. It is now estimated that up to 20% of the global population is afflicted by an allergic disease, with increasing incidence rates in both high- and low-income countries. The World Allergy Organization estimates that the total economic burden of asthma and allergic rhinitis alone is approximately $21 billion per year. While allergic stimuli are a complex and heterogenous class of inputs including parasites, pollens, food antigens, drugs, and metals, it has become clear that fungi are major drivers of allergic disease, with estimates that fungal sensitization occurs in 20-30% of atopic individuals and up to 80% of asthma patients. Fungi are eukaryotic microorganisms that can be found throughout the world in high abundance in both indoor and outdoor environments. Understanding how and why fungi act as triggers of allergic type 2 inflammation will be crucial for combating this important health problem. In recent years, there have been significant advances in our understanding of fungi-induced type 2 immunity, however there is still much we don't understand, including why fungi have a tendency to induce allergic reactions in the first place. Here, we will discuss how fungi trigger type 2 immune responses and posit why this response has been evolutionarily selected for induction during fungal encounter.


Assuntos
Asma , Rinite Alérgica , Humanos , Inflamação , Eucariotos
2.
Mult Scler ; 29(10): 1257-1265, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37537928

RESUMO

BACKGROUND: Thalamic volume (TV) is a sensitive biomarker of disease burden of injury in multiple sclerosis (MS) and appears to reflect overall lesion loads. Ibudilast showed significant treatment effect on brain atrophy and magnetization transfer ratio (MTR) of normal-appearing brain tissue but not in new/enlarging T2 lesion in the SPRINT-MS randomized clinical trial. OBJECTIVE: To evaluate the effect of ibudilast on thalamic tissue integrity and volume in the SPRINT-MS. METHODS: A total of 255 participants with progressive MS were randomized to oral ibudilast or placebo, and thalamic MTR and normalized TV over 96 weeks were quantified. Mixed-effect modeling assessed treatment effects on the thalamic MTR and TV, separately. Similarly, the measures were compared between the participants with confirmed disability progression (CDP). RESULTS: Ibudilast's treatment effect was observed compared to placebo for thalamic MTR (p = 0.03) but not for TV (p = 0.68) while TV correlated with T2 lesion volume (p < 0.001). CDP associated with thalamic MTR (p = 0.04) but not with TV (p = 0.7). CONCLUSION: Ibudilast showed an effect on thalamic MTR, which was associated with CDP, suggesting a clinically relevant effect on thalamic tissue integrity. However, the treatment effect was not observed in TV, suggesting that thalamic atrophy is more closely associated with global inflammatory activity than local tissue integrity. CLINICALTRIALS.GOV: NCT01982942.


Assuntos
Esclerose Múltipla Crônica Progressiva , Esclerose Múltipla , Humanos , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/patologia , Imageamento por Ressonância Magnética , Esclerose Múltipla Crônica Progressiva/diagnóstico por imagem , Esclerose Múltipla Crônica Progressiva/tratamento farmacológico , Esclerose Múltipla Crônica Progressiva/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Piridinas/uso terapêutico , Atrofia/tratamento farmacológico , Atrofia/patologia
3.
Arch Toxicol ; 97(7): 1979-1995, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37202523

RESUMO

The role of non-parenchymal cells (NPCs) in the early phase of acetaminophen (APAP)-induced liver injury (AILI) remains unclear. Therefore, single-cell sequencing (scRNA-seq) was performed to explore the heterogeneity and immune network of NPCs in the livers of mice with AILI. Mice were challenged with saline, 300 mg/kg APAP, or 750 mg/kg APAP (n = 3 for each group). After 3 h, the liver samples were collected, digested, and subjected to scRNA-seq. Immunohistochemistry and immunofluorescence were performed to confirm the expression of Makorin ring finger protein 1 (Mkrn1). We identified 14 distinct cell subtypes among the 120,599 cells. A variety of NPCs were involved, even in the early stages of AILI, indicating highly heterogeneous transcriptome dynamics. Cholangiocyte cluster 3, which had high deleted in malignant brain tumors 1 (Dmbt1) expression, was found to perform drug metabolism and detoxification functions. Liver sinusoidal endothelial cells exhibited fenestrae loss and angiogenesis. Macrophage cluster 1 displayed a M1 polarization phenotype, whereas cluster 3 tended to exhibit M2 polarization. Kupffer cells (KCs) exhibited pro-inflammatory effects due to the high expression of Cxcl2. qRT-PCR and western blotting verified that the LIFR-OSM axis might promote the activation of MAPK signaling pathway in RAW264.7 macrophages. Mkrn1 was highly expressed in the liver macrophages of AILI mice and AILI patients. Interaction patterns between macrophages/KCs and other NPCs were complex and diverse. NPCs were highly heterogeneous and were involved in the immune network during the early phase of AILI. In addition, we propose that Mkrn1 may serve as a potential biomarker of AILI.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Doença Hepática Induzida por Substâncias e Drogas , Animais , Camundongos , Acetaminofen/metabolismo , Células Endoteliais , Fígado , Análise de Sequência de RNA , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Camundongos Endogâmicos C57BL
4.
Artigo em Inglês | MEDLINE | ID: mdl-37944955

RESUMO

Objective: Traditional Chinese medicine (TCM) can achieve similar effects to Western medicine in increasing bone mineral density, improving the destruction of bone micro-structure, inhibiting bone resorption, etc. However, there exist great differences between TCM and Western medicine in terms of theoretical basis and treatment methods. Therefore, to gain insights into their differences in treating osteoporosis (OP), we compared the disease name, etiology, pathogenesis, and clinical effectiveness to explore the potential benefits of combining the two approaches. Methods Overview: The method of literature review is used in the study. We firstly use academic databases such as PubMed and CNKI to search relevant literature on the understanding of OP in TCM and Western medicine in the past 10 years, then exclude the literature that is not relevant to the study topic or does not meet the study purpose, and finally compare and summarize the findings, views and conclusions of the literature. Key Findings or Insights: In the study, we find that the integrated approach of TCM and Western medicine can provide a gentler and more individualized treatment for patients with OP. By combining the conditioning means of Chinese herbs, compound prescription, acupuncture, moxibustion and Tuina can make up for the adverse reactions and side effects of Western medicine. Besides, TCM can make use of the clinical trials and animal experiments of Western medicine to prove the effectiveness of TCM theories and promote the clinical application. Practical Implications: By exploring the differences between TCM and Western medicine and the potential benefits of their combination, this study can provide a theoretical basis for the individualized treatment of OP. Especially for the patients with postmenopausal OP, senile OP, long-term hormone use, hyperthyroidism and other secondary OP, this study can provide a more comprehensive rehabilitation guidance, prevent the recurrence of these diseases, and improve the quality of patients' life. Recommendations or Future Directions: It is suggested that further clinical trials should be conducted to evaluate the effectiveness of the integrated treatment.

5.
Int J Mol Sci ; 24(8)2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37108248

RESUMO

Tumor cells metastasize from a primary lesion to distant organs mainly through hematogenous dissemination, in which tumor cell re-adhesion to the endothelium is essential before extravasating into the target site. We thus hypothesize that tumor cells with the ability to adhere to the endothelium of a specific organ exhibit enhanced metastatic tropism to this target organ. This study tested this hypothesis and developed an in vitro model to mimic the adhesion between tumor cells and brain endothelium under fluid shear stress, which selected a subpopulation of tumor cells with enhanced adhesion strength. The selected cells up-regulated the genes related to brain metastasis and exhibited an enhanced ability to transmigrate through the blood-brain barrier. In the soft microenvironments that mimicked brain tissue, these cells had elevated adhesion and survival ability. Further, tumor cells selected by brain endothelium adhesion expressed higher levels of MUC1, VCAM1, and VLA-4, which were relevant to breast cancer brain metastasis. In summary, this study provides the first piece of evidence to support that the adhesion of circulating tumor cells to the brain endothelium selects the cells with enhanced brain metastasis potential.


Assuntos
Neoplasias Encefálicas , Neoplasias da Mama , Células Neoplásicas Circulantes , Humanos , Feminino , Neoplasias da Mama/metabolismo , Células Neoplásicas Circulantes/patologia , Endotélio/metabolismo , Adesão Celular , Neoplasias Encefálicas/metabolismo , Encéfalo/metabolismo , Metástase Neoplásica/patologia , Endotélio Vascular/metabolismo , Microambiente Tumoral
6.
J Headache Pain ; 24(1): 141, 2023 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-37858040

RESUMO

BACKGROUND: Chronic primary pain (CPP) is an intractable pain of unknown cause with significant emotional distress and/or dysfunction that is a leading factor of disability globally. The lack of a suitable animal model that mimic CPP in humans has frustrated efforts to curb disease progression. 2R, 6R-hydroxynorketamine (2R, 6R-HNK) is the major antidepressant metabolite of ketamine and also exerts antinociceptive action. However, the analgesic mechanism and whether it is effective for CPP are still unknown. METHODS: Based on nociplastic pain is evoked by long-term potentiation (LTP)-inducible high- or low-frequency electrical stimulation (HFS/LFS), we wanted to develop a novel CPP mouse model with mood and cognitive comorbidities by noninvasive low-frequency percutaneous electrical nerve stimulation (LF-PENS). Single/repeated 2R, 6R-HNK or other drug was intraperitoneally (i.p.) or intrathecally (i.t.) injected into naïve or CPP mice to investigate their analgesic effect in CPP model. A variety of behavioral tests were used to detect the changes in pain, mood and memory. Immunofluorescent staining, western blot, reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) and calcium imaging of in cultured dorsal root ganglia (DRG) neurons by Fluo-8-AM were used to elucidate the role and mechanisms of 2R, 6R-HNK in vivo or in vitro. RESULTS: Intrathecal 2R, 6R-HNK, rather than intraperitoneal 2R, 6R-HNK or intrathecal S-Ketamine, successfully mitigated HFS-induced pain. Importantly, intrathecal 2R, 6R-HNK displayed effective relief of bilateral pain hypersensitivity and depressive and cognitive comorbidities in a dose-dependent manner in LF-PENS-induced CPP model. Mechanically, 2R, 6R-HNK markedly attenuated neuronal hyperexcitability and the upregulation of calcitonin gene-related peptide (CGRP), transient receptor potential ankyrin 1 (TRPA1) or vanilloid-1 (TRPV1), and vesicular glutamate transporter-2 (VGLUT2) in peripheral nociceptive pathway. In addition, 2R, 6R-HNK suppressed calcium responses and CGRP overexpression in cultured DRG neurons elicited by the agonists of TRPA1 or/and TRPV1. Strikingly, the inhibitory effects of 2R, 6R-HNK on these pain-related molecules and mechanical allodynia were substantially occluded by TRPA1 antagonist menthol. CONCLUSIONS: In the newly designed CPP model, our findings highlighted the potential utility of intrathecal 2R, 6R-HNK for preventing and therapeutic modality of CPP. TRPA1-mediated uprgulation of CGRP and neuronal hyperexcitability in nociceptive pathways may undertake both unique characteristics and solving process of CPP.


Assuntos
Ketamina , Estimulação Elétrica Nervosa Transcutânea , Animais , Camundongos , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Cálcio/metabolismo , Ketamina/metabolismo , Dor , Canal de Cátion TRPA1
7.
Inf Sci (N Y) ; 628: 469-487, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36777698

RESUMO

The COVID-19 pandemic was caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is a single-stranded positive-stranded RNA virus with a high multi-directional mutation rate. Many new variants even have an immune-evading property, which means that some individuals with antibodies against one variant can be reinfected by other variants. As a result, the realistic is still suffering from new waves of COVID-19 by its new variants. How to control the transmission or even eradicate the COVID-19 pandemic remains a critical issue for the whole world. This work presents an epidemiological framework for mimicking the multi-directional mutation process of SARS-CoV-2 and the epidemic spread of COVID-19 under realistic scenarios considering multiple variants. The proposed framework is used to evaluate single and combined public health interventions, which include non-pharmaceutical interventions, pharmaceutical interventions, and vaccine interventions under the existence of multi-directional mutations of SARS-CoV-2. The results suggest that several combined intervention strategies give optimal results and are feasible, requiring only moderate levels of individual interventions. Furthermore, the results indicate that even if the mutation rate of SARS-CoV-2 decreased 100 times, the pandemic would still not be eradicated without appropriate public health interventions.

8.
Acta Cardiol Sin ; 39(4): 580-598, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37456940

RESUMO

Background: Heart failure is associated with shifts in substrate preferences and energy insufficiency. Although cardiac metabolism has been explored at the organ level, the metabolic changes at the individual cell level remain unclear. This study employed single-cell ribonucleic acid (RNA) sequencing to investigate the cell-type-specific characteristics of gene expression related to fatty acid metabolism. Methods: Single-cell RNA sequencing data from fetal hearts were processed to analyze gene expression patterns related to fatty acid metabolism. Immunofluorescence staining and Western blotting techniques were employed to validate the expression of specific proteins. Additionally, calcium recording and contractility measurements were performed to assess the functional implications of fatty acid metabolism in cardiomyocytes. Results: Based on single-cell RNA sequencing data analysis, we found that a decrease in overall energy requirements underlies the downregulation of fatty acid oxidation-related genes in the later period of heart maturation and the compensatory increase of fatty acid metabolism in individual cardiomyocytes during heart failure. Furthermore, we found that solute carrier family 27 member 6 (SLC27A6), a fatty acid transport protein, is involved in cardiac maturation. SLC27A6 knockdown in human induced pluripotent stem cell-derived cardiomyocytes resulted in an immature cardiomyocyte transcriptional profile, abnormal morphology, impaired Ca2+ handling activity, and contractility. Conclusions: Overall, our study offers a novel perspective for exploring cardiac fatty acid metabolism in fetal and failing hearts along with new insights into the cellular mechanism underlying fatty acid metabolic alterations in individual cardiac cells. It thus facilitates further exploration of cardiac physiology and pathology.

9.
Mult Scler ; 28(2): 198-205, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34014144

RESUMO

BACKGROUND: Detecting cortical demyelination using magnetic resonance imaging (MRI) in multiple sclerosis (MS) remains a challenge. Magnetization transfer ratio (MTR), T1-weighted/T2-weighted ratio (T1T2R), and T2-weighted (T2w) signal are sensitive to cortical demyelination, but their accuracy is unknown. OBJECTIVES: To quantify the sensitivity, specificity, and accuracy of postmortem T1T2R, MTR, and T2w in detecting cortical demyelination. METHODS: In situ postmortem MRIs from 9 patients were used to measure T1T2R, MTR, and T2w along the midline of cortical gray matter and classified as normal or abnormal. MRIs were co-registered and compared to hemispheric myelin staining. The sensitivity, specificity, and accuracy of T1T2R, MTR, and T2w in detecting cortical demyelination were measured. RESULTS: The mean age (standard deviation) at death was 64.7 (+/-13.7) years with a disease duration of 23.8 (+/-10.5) years. The sensitivity was 78% for MTR, 75% for T1T2R, and 63% for T2w. The specificity was 46% (T2w), 13% (T1T2R), and 29% (MTR). The accuracy was 71% (T2w), 39% (MTR), and 42% (T1T2R). There were no significant differences between different MRI measures in cortical demyelination or intracortical/subpial lesion detection. CONCLUSIONS: Although somewhat sensitive, the modest specificity of conventional MRI modalities for cortical demyelination indicates that they are influenced by cortical changes other than demyelination. Improved acquisition and post-processing are needed to reliably measure cortical lesion load.


Assuntos
Imageamento por Ressonância Magnética , Esclerose Múltipla , Idoso , Autopsia , Encéfalo/patologia , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Bainha de Mielina/patologia
10.
Cell Biol Toxicol ; 38(3): 505-530, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34401974

RESUMO

Acetaminophen (APAP) overdose is a common cause of drug-induced liver injury (DILI). Ferroptosis has been recently implicated in APAP-induced liver injury (AILI). However, the functional role and underlying mechanisms of mitochondria in APAP-induced ferroptosis are unclear. In this study, the voltage-dependent anion channel (VDAC) oligomerization inhibitor VBIT-12 and ferroptosis inhibitors were injected via tail vein in APAP-injured mice. Targeted metabolomics and untargeted lipidomic analyses were utilized to explore underlying mechanisms of APAP-induced mitochondrial dysfunction and subsequent ferroptosis. As a result, APAP overdose led to characteristic changes generally observed in ferroptosis. The use of ferroptosis inhibitor ferrostatin-1 (or UAMC3203) and iron chelator deferoxamine further confirmed that ferroptosis was responsible for AILI. Mitochondrial dysfunction, which is associated with the tricarboxylic acid cycle and fatty acid ß-oxidation suppression, may drive APAP-induced ferroptosis in hepatocytes. APAP overdose induced VDAC1 oligomerization in hepatocytes, and protecting mitochondria via VBIT-12 alleviated APAP-induced ferroptosis. Ceramide and cardiolipin levels were increased via UAMC3203 or VBIT-12 in APAP-induced ferroptosis in hepatocytes. Knockdown of Smpd1 and Taz expression responsible for ceramide and cardiolipin synthesis, respectively, aggravated APAP-induced mitochondrial dysfunction and ferroptosis in hepatocytes, whereas Taz overexpression protected against these processes. By immunohistochemical staining, we found that levels of 4-hydroxynonenal (4-HNE) protein adducts were increased in the liver biopsy samples of patients with DILI compared to that in those of patients with autoimmune liver disease, chronic viral hepatitis B, and non-alcoholic fatty liver disease (NAFLD). In summary, protecting mitochondria via inhibiting VDAC1 oligomerization attenuated hepatocyte ferroptosis by restoring ceramide and cardiolipin content in AILI.


Assuntos
Analgésicos não Narcóticos , Doença Hepática Induzida por Substâncias e Drogas , Ferroptose , Canal de Ânion 1 Dependente de Voltagem/metabolismo , Acetaminofen/efeitos adversos , Analgésicos não Narcóticos/metabolismo , Animais , Cardiolipinas/metabolismo , Ceramidas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Hepatócitos/metabolismo , Humanos , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo
11.
J Cell Physiol ; 236(10): 6897-6906, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33650160

RESUMO

Vascular stiffening, an early and common characteristic of cardiovascular diseases (CVDs), stimulates vascular smooth muscle cell (VSMC) proliferation which reciprocally accelerates the progression of CVDs. However, the mechanisms by which extracellular matrix stiffness accompanying vascular stiffening regulates VSMC proliferation remain largely unknown. In the present study, we examined the role of the intermediate-conductance Ca2+ -activated K+  (IKCa ) channel in the matrix stiffness regulation of VSMC proliferation by growing A7r5 cells on soft and stiff polydimethylsiloxane substrates with stiffness close to these of arteries under physiological and pathological conditions, respectively. Stiff substrates stimulated cell proliferation and upregulated the expression of the IKCa channel. Stiff substrate-induced cell proliferation was suppressed by pharmacological inhibition using TRAM34, an IKCa channel blocker, or genetic depletion of the IKCa channel. In addition, stiff substrate-induced cell proliferation was also suppressed by reducing extracellular Ca2+ concentration using EGTA or intracellular Ca2+ concentration using BAPTA-AM. Moreover, stiff substrate induced activation of extracellular signal-regulated kinases (ERKs), which was inhibited by treatment with TRAM34 or BAPTA-AM. Stiff substrate-induced cell proliferation was suppressed by treatment with PD98059, an ERK inhibitor. Taken together, these results show that substrates with pathologically relevant stiffness upregulate the IKCa channel expression to enhance intracellular Ca2+ signaling and subsequent activation of the ERK signal pathway to drive cell proliferation. These findings provide a novel mechanism by which vascular stiffening regulates VSMC function.


Assuntos
Sinalização do Cálcio , Proliferação de Células , Dimetilpolisiloxanos/química , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/metabolismo , Mecanotransdução Celular , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Animais , Técnicas de Cultura de Células , Linhagem Celular , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/genética , Ratos
12.
Mult Scler ; 27(14): 2159-2169, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33749379

RESUMO

OBJECTIVE: Describe magnetic resonance imaging (MRI) susceptibility changes in progressive multifocal leukoencephalopathy (PML) and identify neuropathological correlates. METHODS: PML cases and matched controls with primary central nervous system lymphoma (PCNSL) were retrospectively identified. MRI brain at 3 T and 7 T were reviewed. MRI-pathology correlations in fixed brain autopsy tissue were conducted in three subjects with confirmed PML. RESULTS: With PML (n = 26 total, n = 5 multiple sclerosis natalizumab-associated), juxtacortical changes on susceptibility-weighted imaging (SWI) or gradient echo (GRE) sequences were noted in 3/3 cases on 7 T MRI and 14/22 cases (63.6%) on 1.5 T or 8/22 (36.4%) 3 T MRI. Similar findings were only noted in 3/25 (12.0%) of PCNSL patients (odds ratio (OR) 12.83, 95% confidence interval (CI), 2.9-56.7, p < 0.001) on 1.5 or 3 T MRI. On susceptibility sequences available prior to diagnosis of PML, 7 (87.5%) had changes present on average 2.7 ± 1.8 months (mean ± SD) prior to diagnosis. Postmortem 7 T MRI showed SWI changes corresponded to areas of increased iron density along the gray-white matter (GM-WM) junction predominantly in macrophages. CONCLUSION: Susceptibility changes in PML along the GM-WM junction can precede noticeable fluid-attenuated inversion recovery (FLAIR) changes and correlates with iron accumulation in macrophages.


Assuntos
Leucoencefalopatia Multifocal Progressiva , Substância Branca , Encéfalo/diagnóstico por imagem , Humanos , Ferro , Leucoencefalopatia Multifocal Progressiva/diagnóstico por imagem , Macrófagos , Imageamento por Ressonância Magnética , Natalizumab , Estudos Retrospectivos , Substância Branca/diagnóstico por imagem
13.
J Cell Mol Med ; 24(6): 3739-3744, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32065503

RESUMO

Mechanical stimulation is an important factor regulating mesenchymal stem cell (MSC) functions such as proliferation. The Ca2+ -activated K+ channel, KCa 3.1, is critically engaged in MSC proliferation but its role in mechanical regulation of MSC proliferation remains unknown. Here, we examined the KCa 3.1 channel expression and its role in rat bone marrow-derived MSC (BMSC) proliferation in response to mechanical stretch. Application of mechanical stretch stimulated BMSC proliferation via promoting cell cycle progression. Such mechanical stimulation up-regulated the KCa 3.1 channel expression and pharmacological or genetic inhibition of the KCa 3.1 channel strongly suppressed stretch-induced increase in cell proliferation and cell cycle progression. These results support that the KCa 3.1 channel plays an important role in transducing mechanical forces to MSC proliferation. Our finding provides new mechanistic insights into how mechanical stimuli regulate MSC proliferation and also a viable bioengineering approach to improve MSC proliferation.


Assuntos
Canais de Potássio Ativados por Cálcio de Condutância Intermediária/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Estresse Mecânico , Animais , Proliferação de Células , Masculino , Ratos Sprague-Dawley
14.
Invest New Drugs ; 38(1): 20-28, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-30887251

RESUMO

F-box proteins, a type of substrate-recognition complexes consisting of SKP1-cullin 1-F-box protein (SCF) E3 ligase, can critically affect many cellular processes because of the ubiquitylation and subsequent degradation of target proteins. This study investigated the effect of FBXO22 on melanoma angiogenesis, migration, and invasion. Results showed that FBXO22 staining intensity was increased in malignant melanoma (MM) compared with that in skin tissue (P˂0.001). The percentage of high FBXO22 expression in MM (74.3%) was markedly higher than that in paracancerous and skin tissues (0%) (P˂0.001). FBXO22 was also overexpressed in MM tissues compared with that in normal skin tissues. FBXO22 knockdown in vitro inhibited MM cell migration, invasion, and angiogenesis (P < 0.001). In vivo studies confirmed that using nude mice with knocked down FBXO22 reduced the formation of blood vessels and decreased the positive rate of CD31 (P < 0.05). HIF-1α expression varied with FBXO22, indicating that FBXO22 regulated the expression of HIF-1α and VEGFA and that FBXO22 was a regulator of HIF-1α and VEGF for the control of tumor angiogenesis. In conclusion, FBXO22 promoted the migration and invasion of tumor cells and melanoma angiogenesis via HIF-1α upregulation. This study demonstrated that FBXO22 knockdown suppressed tumor progression and metastasis, suggesting that FBXO22 might be developed as a novel target for treating patients with MM.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas F-Box/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Melanoma/patologia , Neovascularização Patológica/patologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Ciclo Celular , Movimento Celular , Proliferação de Células , Proteínas F-Box/antagonistas & inibidores , Proteínas F-Box/genética , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Melanoma/genética , Melanoma/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Prognóstico , RNA Interferente Pequeno/genética , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/genética , Transdução de Sinais , Células Tumorais Cultivadas , Ubiquitinação , Fator A de Crescimento do Endotélio Vascular/genética , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Acta Cardiol Sin ; 34(2): 115-123, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29643696

RESUMO

Heart regeneration remains a critical question in current basic research and clinical practice. The adult mammalian heart exhibits a very limited regeneration capacity. In contrast, adult zebrafish and neonatal mice retain a remarkable ability of heart regeneration after damage. Understanding the mechanisms of heart regeneration would be very valuable to help design efficient treatment strategies against myocardial damage and heart failure. While inherent regeneration of the heart occurs after damage with varying efficiency among species, regeneration may also be induced exogenously. In this study, we briefly review the different approaches and current progress in improving heart regeneration.

17.
Nat Commun ; 15(1): 3799, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714769

RESUMO

Intriguing "slidetronics" has been reported in van der Waals (vdW) layered non-centrosymmetric materials and newly-emerging artificially-tuned twisted moiré superlattices, but correlative experiments that spatially track the interlayer sliding dynamics at atomic-level remain elusive. Here, we address the decisive challenge to in-situ trace the atomic-level interlayer sliding and the induced polarization reversal in vdW-layered yttrium-doped γ-InSe, step by step and atom by atom. We directly observe the real-time interlayer sliding by a 1/3-unit cell along the armchair direction, corresponding to vertical polarization reversal. The sliding driven only by low energetic electron-beam illumination suggests rather low switching barriers. Additionally, we propose a new sliding mechanism that supports the observed reversal pathway, i.e., two bilayer units slide towards each other simultaneously. Our insights into the polarization reversal via the atomic-scale interlayer sliding provide a momentous initial progress for the ongoing and future research on sliding ferroelectrics towards non-volatile storages or ferroelectric field-effect transistors.

18.
Front Psychol ; 14: 1113973, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37008873

RESUMO

Cross-linguistic features of light verb constructions (LVCs) profile a major facet of the typological difference between Chinese and English. By adopting a theory-driven, context-based interpreting task, this study explores the effectiveness and variability of translation strategies in dealing with 12 target LVCs extracted from a Chinese-English Consecutive Interpreting test to capture effective translation strategies fit for Chinese English-as-foreign-language (EFL) learners (N = 66). Appropriate rates and entropy values denoting variability of strategy selection are calculated by using 12 LVC segments and nine strategies, respectively. A correlation test is also carried out for vocabulary knowledge and the appropriate rates of LVCs to assess the efficacy of learners' vocabulary knowledge in interpreting performance. Results show the general preferences for strategy selection among Chinese EFL learners as well as typical structural patterns in LVC translation. The degree of lightness of the light verbs exerts a reverse effect on the appropriate rates and consistency of strategy selection, and the positive correlation between vocabulary knowledge and LVCs' appropriate rates suggests the need to incorporate the constructional teaching into the EFL learning curriculum. Thus felicitous conditions of applying the strategies have been proposed.

19.
Nanomaterials (Basel) ; 13(3)2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36770333

RESUMO

With the rapid development of artificial intelligence and the Internet of Things, there is an explosion of available data for processing and analysis in any domain. However, signal processing efficiency is limited by the Von Neumann structure for the conventional computing system. Therefore, the design and construction of artificial synapse, which is the basic unit for the hardware-based neural network, by mimicking the structure and working mechanisms of biological synapses, have attracted a great amount of attention to overcome this limitation. In addition, a revolution in healthcare monitoring, neuro-prosthetics, and human-machine interfaces can be further realized with a flexible device integrating sensing, memory, and processing functions by emulating the bionic sensory and perceptual functions of neural systems. Until now, flexible artificial synapses and related neuromorphic systems, which are capable of responding to external environmental stimuli and processing signals efficiently, have been extensively studied from material-selection, structure-design, and system-integration perspectives. Moreover, low-dimensional materials, which show distinct electrical properties and excellent mechanical properties, have been extensively employed in the fabrication of flexible electronics. In this review, recent progress in flexible artificial synapses and neuromorphic systems based on low-dimensional materials is discussed. The potential and the challenges of the devices and systems in the application of neuromorphic computing and sensory systems are also explored.

20.
SN Appl Sci ; 4(4): 107, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35330957

RESUMO

Optimization of machining parameters like cutting speed, feed, and depth of cut is one of the extensively studied fields in the past two decades. While researchers agree optimization of these parameters is essential, there is no conscience as to what the objective of the optimization should be. The studies consider production cost, production time, surface finish, among others, as the objective of parameter optimization, but there are very few studies that consider the manufacturer prescribed tool life as the criteria for parament optimization. Among the methods that do consider tool life as an optimization objective, very few are closed-loop systems and these systems are facing challenges to generalizing when the application changes or the machining material changes or the tool geometry changes. Considering this, a novel image feedback using a convolution neural network-based method combined with principles of fuzzy logic is used to optimize machining parameters. Since the system is based on online feedback from the images of the inserts, it can be used for different materials, and the system is invariant to the different tool geometries and grades as the decisions are based on the wear mechanisms detected. The hybrid system is validated through experimentation for the turning application, but the methodology can be easily adapted for other machining applications.

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