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Climate warming has become a global issue of close concern, and China, as a significant agricultural country, has an increasing demand for food, which requires China to increase carbon reduction in this industry. This paper accounts for carbon emissions from the food production industry (CEFI) using the input-output method, then screens the influencing factors of CEFI based on Random Forest (RF), analyzes the heterogeneous effects of the influencing factors on CEFI in different clusters through K-means-SHAP, and finally explores the potential of carbon emissions from this industry for the period 2024-2040. The study's findings are as follows: First, there are apparent inequalities in CEFI, especially between provinces, which are gradually increasing. Second, addressing people's consumption awareness and behaviors is not the fundamental solution to alleviate CEFI; instead, it should focus on sustainable agricultural production transformation and "food miles" in the transportation phase. In addition, attention needs to be paid to the impacts of fertilizer application, transport modes, and livestock management on the CEFI of each cluster. Finally, the study suggests that around 2028, 70% of China's provinces will be at the "carbon peak" and that less developed and more developed regions have more significant potential to reduce emissions. In this regard, this paper encourages a series of policies that are key to promoting the sustainable development of CEFI, such as reducing the volume and efficiency of traditional fertilizers, vigorously developing organic fertilizer inputs, strengthening technological innovation and R&D inputs in the transportation sector, and steadily supporting germplasm innovation in the livestock sector.
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Carbono , China , Carbono/análise , Indústria Alimentícia , Agricultura/métodosRESUMO
BACKGROUND: Cardiac iron overload and ferroptosis greatly contribute to the poor prognosis of myocardial infarction (MI). Iron chelator is one of the most promising strategies for scavenging excessive iron and alleviating cardiac dysfunction post MI. However, various side effects of existing chemical iron chelators restrict their clinical application, which calls for a more viable and safer approach to protect against iron injury in ischemic hearts. RESULTS: In this study, we isolated macrophage-derived extracellular vesicles (EVs) and identified macrophage-derived EVs as a novel endogenous biological chelator for iron. The administration of macrophage-derived EVs effectively reduced iron overload in hypoxia-treated cardiomyocytes and hearts post MI. Moreover, the oxidative stress and ferroptosis induced by excessive iron were considerably suppressed by application of macrophage-derived EVs. Mechanistically, transferrin receptor (TfR), which was inherited from macrophage to the surface of EVs, endowed EVs with the ability to bind to transferrin and remove excess protein-bound iron. EVs with TfR deficiency exhibited a loss of function in preventing MI-induced iron overload and protecting the heart from MI injury. Furthermore, the iron-chelating EVs were ultimately captured and processed by macrophages in the liver. CONCLUSIONS: These results highlight the potential of macrophage-derived EVs as a powerful endogenous candidate for iron chelation therapy, offering a novel and promising therapeutic approach to protect against iron overload-induced injury in MI and other cardiovascular diseases.
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Vesículas Extracelulares , Quelantes de Ferro , Sobrecarga de Ferro , Macrófagos , Camundongos Endogâmicos C57BL , Infarto do Miocárdio , Receptores da Transferrina , Infarto do Miocárdio/metabolismo , Animais , Vesículas Extracelulares/metabolismo , Sobrecarga de Ferro/metabolismo , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Camundongos , Quelantes de Ferro/farmacologia , Quelantes de Ferro/uso terapêutico , Receptores da Transferrina/metabolismo , Masculino , Ferro/metabolismo , Miócitos Cardíacos/metabolismo , Ferroptose/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Transferrina/metabolismo , HumanosRESUMO
OBJECTIVES: To compare early outcomes of proximal femoral bionic nail (PFBN), Inter-TAN, proximal femoral nail antirotation (PFNA) for intertrochanteric fractures in elderly patients. METHODS: Eighty-two elderly patients with intertrochanteric femoral fractures treated at Xiangyang No. 1 People's Hospital affiliated with Hubei University of Medicine from December 2021 to 2022 were retrospectively analyzed. They were categorized into three surgical groups: PFBN (22 cases), Inter-TAN (20 cases), and PFNA (40 cases). Preoperative demographics and fracture characteristics were compared, alongside intraoperative and postoperative metrics like operative time and complication rates. RESULTS: In the PFBN group, operative time, fluoroscopy use, blood loss, and transfusion were higher, but postoperative weight-bearing, healing, and hospital stay were shorter compared to the Inter-TAN and PFNA groups (P<0.05). Inter-TAN had a significantly shorter postoperative weight-bearing time than PFNA (P<0.001). Other compared factors showed no significant differences between groups (P>0.05), including complication rates and scores at 6-month follow-up. CONCLUSIONS: PFBN, a novel surgical approach for intertrochanteric fractures in elderly patients, outperforms Inter-TAN and PFNA by accelerating early weight-bearing and hastening fracture recovery.
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Fixação Intramedular de Fraturas , Fraturas do Quadril , Humanos , Feminino , Fixação Intramedular de Fraturas/métodos , Fixação Intramedular de Fraturas/efeitos adversos , Masculino , Idoso , Fraturas do Quadril/cirurgia , Estudos Retrospectivos , Idoso de 80 Anos ou mais , Resultado do Tratamento , Pinos Ortopédicos , Suporte de Carga/fisiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologiaRESUMO
BACKGROUND: Glioma is the most malignant primary brain tumor with a poor survival time. The tumour microenvironment, especially glioma-associated microglia/macrophages (GAMs), plays an important role in the pathogenesis of glioma. Currently, microglia (CD11b+/CD45Low) and macrophages (CD11b+/CD45High) are distinguished as distinct cell types due to their different origins. Moreover, signal-transducing adaptor protein 1 (STAP1) plays a role in tumourigenesis and immune responses. However, to date, no studies have been reported on STAP1 in GAMs. METHODS: The Cancer Genome Atlas and Chinese Glioma Genome Atlas databases were used to investigate the association between STAP1 mRNA levels and clinical parameters (grades, mutations in isocitrate dehydrogenase, and overall survival). RNA-sequencing, qRT-PCR, Western blotting, immunohistochemistry and immunofluorescence analyses were performed to detect the expression level of STAP1 and related proteins. BV-2 cells were used to construct a STAP1-overexpressing cell line. Phagocytosis of BV-2 cells was assessed by flow cytometry and fluorescence microscopy. C57BL/6 mice were used to establish orthotopic and subcutaneous glioma mouse models. Glioma growth was monitored by bioluminescence imaging. RESULTS: STAP1 expression in glioma-associated microglia is positively correlated with the degree of malignancy and poor prognosis of glioma. Moreover, STAP1 may promote M2-like polarisation by increasing ARG1 expression and inhibiting microglial phagocytosis of microglia. Increased ARG1 may be associated with the IL-6/STAT3 pathway. Impaired phagocytosis may be associated with decreased cofilin and filopodia. CONCLUSION: STAP1 is positively associated with the degree of glioma malignancy and may represent a potential novel therapeutic target for glioma.
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Neoplasias Encefálicas , Glioma , Camundongos , Animais , Microglia , Linhagem Celular Tumoral , Camundongos Endogâmicos C57BL , Glioma/metabolismo , Macrófagos , Neoplasias Encefálicas/metabolismo , Microambiente TumoralRESUMO
BACKGROUND: Precise quantification of grafted human cells in preclinical animal models such as non-human primates, rodents and rabbits is needed for the evaluations of the safety and efficacy of cell therapy. Quantitative PCR (qPCR) as a swift, sensitive and powerful assay is suitable for human cell quantification. However, it is a formidable challenge due to that the genome of non-human primates share more than 95% of similarity as human. METHODS: In the present study, we developed a probe-based quantitative PCR (qPCR) assay for the quantification of human cells in preclinical animal models via targeting human specific DNA in the intron of BRCA1 (termed BRCA1-qPCR). The 5' and 3' end of BRCA1-qPCR probe was conjugated with FAM and non-fluorescent quencher-minor groove binder (NFQ-MGB), respectively. 1 µg of genomic DNA from human and preclinical animal models including rhesus monkeys, cynomolgus monkeys, New Zealand white rabbits, SD rats, C57BL/6 and BALB/c mice were used for determining the specificity and sensitivity of the BRCA1-qPCR assay. A calibration curve was generated by BRCA1-qPCR analysis of linearized plasmid containing targeted human specific DNA in BRCA1. The BRCA1-qPCR assay was validated by analysis of 0.003%, 0.03% and 0.3% of human leukocytes mixed within murine leukocytes. RESULTS: The BRCA1-qPCR assay detected human DNA rather than DNA from tested species. The amplification efficiency of the BRCA1-qPCR assay was 95.4% and the linearity of the calibration curve was R2 = 0.9997. The BRCA1-qPCR assay detected as low as 5 copies of human specific DNA and is efficient to specially amplify 30 pg human DNA in the presence of 1 µg of genomic DNA from tested species, respectively. The BRCA1-qPCR assay was able to quantify as low as 0.003% of human cells within murine leukocytes. CONCLUSION: The BRCA1-qPCR assay is efficient for the quantification of human cells in preclinical animal models.
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DNA , Primatas , Humanos , Animais , Ratos , Camundongos , Coelhos , Íntrons , Camundongos Endogâmicos C57BL , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase , Modelos Animais , Proteína BRCA1/genéticaRESUMO
STUDY OBJECTIVES: This study aims to investigate the extent to which sleep duration and efficiency are associated with plasma amyloid-ß (Aß) levels in non-demented older people. METHODS: This study is a cross-sectional analysis of 305 non-demented older people. Sleep duration and efficiency were assessed used the Pittsburgh Sleep Quality Index. Levels of plasma Aß were determined by sandwich enzyme-linked immunosorbent assay technique. Associations between sleep variables and plasma Aß levels were evaluated with multivariable linear regression analysis. RESULTS: Compared to those with sleep duration > 7 h, participants with sleep duration < 6 h had a higher plasma Aß42 level (ß = 0.495, 95% CI 0.077~0.913, p = 0.021) and Aß42/Aß40 ratio (ß = 0.101, 95% CI 0.058~0.144, p < 0.001). Compared to those with sleep efficiency ≥ 85%, participants with lower sleep efficiency (65~74%, <65%) had a higher level of plasma Aß42 (<65%: ß = 0.627, 95% CI 0.147~1.108, p = 0.011) and Aß42/Aß40 ratio (65~74%: ß = 0.052, 95% CI 0.007~0.097, p = 0.026; <65%: ß = 0.117, 95% CI 0.067~0.168, p < 0.001). CONCLUSIONS: These findings indicated that short sleep duration and low sleep efficiency were associated with a high level of Aß42. A better comprehending of the link between sleep and plasma Aß levels may lead to effective sleep-based intervention to reduce the risk of Alzheimer's disease.
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Peptídeos beta-Amiloides , Fragmentos de Peptídeos , Sono , Idoso , Doença de Alzheimer , Peptídeos beta-Amiloides/sangue , Biomarcadores , Estudos Transversais , Humanos , Fragmentos de Peptídeos/sangue , Qualidade do SonoRESUMO
BACKGROUND: Previous studies have found that the microenvironment of cervical cancer (CESC) affects the progression and treatment of this disease. Thus, we constructed a multigene model to assess the survival of patients with cervical cancer. METHODS: We scored 307 CESC samples from The Cancer Genome Atlas (TCGA) and divided them into high and low matrix and immune scores using the ESTIMATE algorithm for differential gene analysis. Cervical cancer patients were randomly divided into a training group, testing group and combined group. The multigene signature prognostic model was constructed by Cox analyses. Multivariate Cox analysis was applied to evaluate the significance of the multigene signature for cervical cancer prognosis. Prognosis was assessed by Kaplan-Meier curves comparing the different groups, and the accuracy of the prognostic model was analyzed by receiver operating characteristic-area under the curve (ROC-AUC) analysis and calibration curve. The Tumor Immune Estimation Resource (TIMER) database was used to analyze the relationship between the multigene signature and immune cell infiltration. RESULTS: We obtained 420 differentially expressed genes in the tumor microenvironment from 307 patients with cervical cancer. A three-gene signature (SLAMF1, CD27, SELL) model related to the tumor microenvironment was constructed to assess patient survival. Kaplan-Meier analysis showed that patients with high risk scores had a poor prognosis. The ROC-AUC value indicated that the model was an accurate predictor of cervical cancer prognosis. Multivariate cox analysis showed the three-gene signature to be an independent risk factor for the prognosis of cervical cancer. A nomogram combining the three-gene signature and clinical features was constructed, and calibration plots showed that the nomogram resulted in an accurate prognosis for patients. The three-gene signature was associated with T stage, M stage and degree of immune infiltration in patients with cervical cancer. CONCLUSIONS: This research suggests that the developed three-gene signature may be applied as a biomarker to predict the prognosis of and personalized therapy for CESC.
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Cardiovascular diseases are a main cause of mortality whose prevalence continues to increase worldwide. Long non-coding RNAs (lncRNAs) regulate a variety of biological processes by modifying and regulating transcription of coding genes, directly binding to proteins and even coding proteins themselves. LncRNAs play key roles in the occurrence and development of myocardial infarction, heart failure, myocardial hypertrophy, arrhythmias and other pathological processes that significantly affect the prognosis and survival of patients with cardiovascular diseases. We here review the latest research on lncRNAs in cardiovascular diseases as a basis to formulate future research on prevention and treatment of cardiovascular diseases.
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Doenças Cardiovasculares/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/fisiologia , Animais , Apoptose , Arritmias Cardíacas/metabolismo , Aterosclerose/metabolismo , Autofagia , Biomarcadores/metabolismo , Cardiologia/tendências , Cardiomiopatia Dilatada/metabolismo , Doenças Cardiovasculares/patologia , Proliferação de Células , Insuficiência Cardíaca , Histonas/metabolismo , Humanos , Inflamação , Metabolismo dos Lipídeos , Metilação , Infarto do Miocárdio/metabolismo , Prognóstico , Ligação Proteica , Transdução de Sinais , Resultado do TratamentoRESUMO
Sirt6 has been reported to play a protective role in macrophage foam cell formation, but whether Sirt6 controls atherosclerosis plaque stability and whether it can reduce the interaction between endothelial cells and macrophages remains unclear. The aim of this study was to investigate the effect of Sirt6 on atherosclerosis plaque stability and the underlying mechanisms. We used Tie2-Cre transgenic mice as a Cre-lox tool to delete Sirt6 floxed sequences in endothelial cells during adulthood to establish Sirt6-/- mice. ApoE-/-:Sirt6-/- and ApoE-/-:Sirt6Tg mice were used in our investigation. After a 16 week high-fat diet, the mice developed markedly atherosclerotic plaques. Sirt6 knockout exacerbated atherosclerotic plaque progression in both size and stability. In vitro, murine macrophage RAW264.7 cells were treated with ox-low density lipoproteins for 24 h to simulate atherosclerosis. Furthermore, Sirt6 overexpression remarkably increased autophagic flux in macrophages and inhibited macrophage apoptosis. Moreover, Sirt6 overexpression inhibited the expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and platelet selectin (P-selectin), leading to reduced infiltration of macrophages and foam cells. In conclusion, our study indicates a new mechanism-based strategy to therapeutically stimulate atherosclerosis plaque stability.
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Aterosclerose/metabolismo , Autofagia , Células Endoteliais/citologia , Macrófagos/citologia , Placa Aterosclerótica/genética , Sirtuínas/genética , Animais , Aterosclerose/genética , Progressão da Doença , Células Espumosas/metabolismo , Inflamação , Molécula 1 de Adesão Intercelular/metabolismo , Lipoproteínas LDL/metabolismo , Masculino , Camundongos , Camundongos Knockout para ApoE , Selectina-P/metabolismo , Células RAW 264.7 , Receptor TIE-2/genética , Sirtuínas/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismoRESUMO
BACKGROUND: Euglena is a new super health food resource that is rich in the natural polysaccharide paramylon, a linear ß-1,3-glucan with various biological activities including activity on the immune system in different cell lines and animals. Despite these reports, the immune regulation mechanism of paramylon is still unclear. RESULTS: We investigate the signaling pathways paramylon impacts in immune macrophages. In RAW264.7 macrophages, sonicated and alkalized paramylon oligomers up-regulated inducible nitric oxide synthase (iNOS) and increased secretion of nitric oxide (NO), interleukin (IL)-6 and tumor necrosis factor (TNF)-α, in a concentration-dependent manner. In addition, paramylon activated the nuclear factor-κB(NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways and inhibiting these pathways attenuated the paramylon-induced secretion of the above immune-mediators. CONCLUSIONS: These results demonstrate that Euglena gracilis paramylon modulates the immune system via activation of the NF-κB and MAPK signaling pathways and thus has potential therapeutic benefits.
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Euglena gracilis/metabolismo , Glucanos/farmacologia , Macrófagos/parasitologia , Transdução de Sinais/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Glucanos/imunologia , Interleucina-6/metabolismo , Ativação de Macrófagos , Macrófagos/imunologia , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7 , Sonicação , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Smooth muscle cells (SMCs), which form the walls of blood vessels, play an important role in vascular development and the pathogenic process of vascular remodeling. However, the molecular mechanisms governing SMC differentiation remain poorly understood. Glycoprotein M6B (GPM6B) is a four-transmembrane protein that belongs to the proteolipid protein family and is widely expressed in neurons, oligodendrocytes, and astrocytes. Previous studies have revealed that GPM6B plays a role in neuronal differentiation, myelination, and osteoblast differentiation. In the present study, we found that the GPM6B gene and protein expression levels were significantly upregulated during transforming growth factor-ß1 (TGF-ß1)-induced SMC differentiation. The knockdown of GPM6B resulted in the downregulation of SMC-specific marker expression and repressed the activation of Smad2/3 signaling. Moreover, GPM6B regulates SMC Differentiation by Controlling TGF-ß-Smad2/3 Signaling. Furthermore, we demonstrated that similar to p-Smad2/3, GPM6B was profoundly expressed and coexpressed with SMC differentiation markers in embryonic SMCs. Moreover, GPM6B can regulate the tightness between TßRI, TßRII, or Smad2/3 by directly binding to TßRI to activate Smad2/3 signaling during SMC differentiation, and activation of TGF-ß-Smad2/3 signaling also facilitate the expression of GPM6B. Taken together, these findings demonstrate that GPM6B plays a crucial role in SMC differentiation and regulates SMC differentiation through the activation of TGF-ß-Smad2/3 signaling via direct interactions with TßRI. This finding indicates that GPM6B is a potential target for deriving SMCs from stem cells in cardiovascular regenerative medicine. Stem Cells 2018 Stem Cells 2019;37:190-201.
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Glicoproteínas de Membrana/metabolismo , Miócitos de Músculo Liso/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Proteína Smad2/metabolismo , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta3/metabolismo , Animais , Diferenciação Celular/fisiologia , Células HEK293 , Humanos , Camundongos , Miócitos de Músculo Liso/citologia , Transdução de Sinais , Transfecção , Regulação para CimaRESUMO
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of the outbreak of coronavirus disease 2019 in Wuhan City, China. The SARS-CoV-2 is genetically similar to the coronavirus derived from bat. The SARS-CoV-2, the SARS-CoV and the Middle East respiratory syndrome coronavirus (MERS-CoV) all belong to beta coronavirus. Since the outbreak of the coronavirus disease 2019, effective antiviral drugs have become a hot issue in the world. Very little about SARS-CoV-2 is known and there is no precedent for treatment. The National Health Commission has repeatedly revised the diagnosis and treatment guide for the coronavirus disease 2019. The latest guide is "New Coronary Virus-Infected Pneumonia Diagnosis and Treatment Plan (Seventh Trial Version)"(short for Seventh Version of Diagnosis and Treatment Plan). But the use of antiviral drugs is still on trial and no rigorous clinical trials data is available. Hot anti-SARS-CoV-2 drugs include interferon α, ribavirin, lopinavir/ritonavir, chloroquine phosphate, abidol, as well as hydroxychloroquine sulfate and remdesivir. But the later 2 drugs aren't mentioned in the Seventh Version of Diagnosis and Treatment Plan.
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Antivirais/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Pneumonia Viral/tratamento farmacológico , Betacoronavirus , COVID-19 , China , Humanos , Pandemias , Guias de Prática Clínica como Assunto , SARS-CoV-2 , Tratamento Farmacológico da COVID-19RESUMO
In the original article, Zaiqiang Zhang was affiliated to Department of Neurology, Beijing Hospital, National Center of Gerontology, Beijing, China. The corrected affiliation should be: Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
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Chemotherapy-induced peripheral neuropathy (CIPN) is a common adverse side effect of many antineoplastic agents. Patients treated with chemotherapy often report pain and paresthesias in a "glove-and-stocking" distribution. Diverse mechanisms contribute to the development and maintenance of CIPN. However, the role of spinal microglia in CIPN is not completely understood. In this study, cisplatin-treated mice displayed persistent mechanical allodynia, sensory deficits and decreased density of intraepidermal nerve fibers (IENFs). In the spinal cord, activation of microglia, but not astrocyte, was persistently observed until week five after the first cisplatin injection. Additionally, mRNA levels of inflammation related molecules including IL-1ß, IL-6, tumor necrosis factor (TNF)-α, inducible nitric oxide synthase (iNOS) and CD16, were increased after cisplatin treatment. Intraperitoneal (i.p.) or intrathecal (i.t.) injection with minocycline both alleviated cisplatin-induced mechanical allodynia and sensory deficits, and prevented IENFs loss. Furthermore, cisplatin enhanced triggering receptor expressed on myeloid cells 2 (TREM2) /DNAX-activating protein of 12â¯kDa (DAP12) signaling in the spinal cord microglia. The blockage of TREM2 by i.t. injecting anti-TREM2 neutralizing antibody significantly attenuated cisplatin-induced mechanical allodynia, sensory deficits and IENFs loss. Meanwhile, anti-TREM2 neutralizing antibody prominently suppressed the spinal IL-6, TNF-α, iNOS and CD16 mRNA level, but it dramatically up-regulated the anti-inflammatory cytokines IL-4 and IL-10. The data demonstrated that cisplatin triggered persistent activation of spinal cord microglia through strengthening TREM2/DAP12 signaling, which further resulted in CIPN. Functional blockage of TREM2 or inhibition of microglia both benefited for cisplatin-induced peripheral neuropathy. Microglial TREM2/DAP12 may serve as a potential target for CIPN intervention.
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Glicoproteínas de Membrana/metabolismo , Doenças do Sistema Nervoso Periférico/imunologia , Doenças do Sistema Nervoso Periférico/metabolismo , Receptores Imunológicos/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Astrócitos/metabolismo , Cisplatino/efeitos adversos , Citocinas/metabolismo , Modelos Animais de Doenças , Hiperalgesia/metabolismo , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Interleucina-4/metabolismo , Interleucina-6/metabolismo , Ativação de Macrófagos , Masculino , Glicoproteínas de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Microglia/fisiologia , Minociclina/farmacologia , Óxido Nítrico Sintase Tipo II/metabolismo , Dor/metabolismo , Receptores de IgG/metabolismo , Receptores Imunológicos/fisiologia , Transdução de Sinais , Medula Espinal/patologia , Medula Espinal/fisiologia , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Two novel polyoxovanadate (POV)-containing fluorosurfactants, each with two hydrophobic fluorinated "tails" and one nanosized, hydrophilic, rigid POV "head group", are synthesized for the first time. They self-assemble into spherical, bilayer vesicles in acetonitrile/water mixed solvents, as evidenced by systemic studies using laser light scattering (LLS) and electron microscopy techniques. The vesicle sizes demonstrate dynamic change over different solvent compositions mainly as a result of the solvent swelling of the fluorocarbon chains, although the charge number on the POVs changes over the solvent polarity as well.
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The behavior in dilute solution of phosphate-functionalized γ-cyclodextrin macroanions with eight charges on the rim was explored. The hydrophilic macroions in mixed solvents show strong attraction between each other, mediated by the counterions, and consequently self-assemble into blackberry-type hollow spherical structures. Time-resolved laser light scattering (LLS) measurements at high temperature ruled out the possibility of hydrogen bonding as the main driving force in the self-assembly and indicated the good thermodynamic stability of assemblies regulated by the charge. The transition from single macroions to blackberries can be tuned by adjusting the content of organic solvent. The sizes of blackberries vary with the charge density of γ-cyclodextrin by adjusting pH. It is the first report that pure cyclodextrins can generate supramolecular structures by themselves in dilute solution. The unique solution behavior of macroions provides a new opportunity to assemble cyclodextrin into functional materials and devices.
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The precise guidance to different ions across the biological channels is essential for many biological processes. An artificial nanopore system will facilitate the study of the ion-transport mechanism through nanosized channels and offer new views for designing nanodevices. Herein we reveal that a 2.5 nm-sized, fullerene-shaped molecular cluster Li48+m K12(OH)m [UO2(O2)(OH)]60-(H2O)n (m ≈ 20 and n ≈ 310) (U60) shows selective permeability to different alkali ions. The subnanometer pores on the water-ligand-rich surface of U60 are able to block Rb(+) and Cs(+) ions from passing through, while allowing Na(+) and K(+) ions, which possess larger hydrated sizes, to enter the interior space of U60. An interestingly high entropy gain during the binding process between U60 and alkali ions suggests that the hydration shells of Na(+)/K(+) and U60 are damaged during the interaction. The ion selectivity of U60 is greatly influenced by both the morphologies of the surface nanopores and the dynamics of the hydration shells.
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CONTEXT: Pharmaceutical solid dispersions are known to be seriously affected by issues of aging and processing. OBJECTIVE: This study investigated the spectral patterns in the solid dispersions (SD) of Nifedipine/Soluplus/Kollidon SR and the feasibility of the methodology in identification and evaluation of the solid dispersions. METHODS: The SD samples were prepared by hot melt extrusion (HMESD), solvent-evaporation (SESD), and fusion-cooling (FCSD). In order to distinguish the different SD samples, a combined analytical strategy by FT-IR spectrum, Raman spectrum, and computational approaches (PCA and HCA) were developed to investigate the spectral patterns of the solid dispersions. Differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), scanning electron microscope (SEM), and dissolution test were employed as the reference characterization. The stability test under the accelerated condition was carried out to investigate the physical stability of the SDs. RESULT: For the three prepared SDs, the evident differences on the dissolution behaviors and the trend of aging was observed. By means of the combined analytical strategy, the samples could be successfully identified in terms of their preparing techniques. The strength of hydrogen bonding interaction between NF and polymers decreased in the order of HMESD > SESD > FCSD. The results of the stability test indicated that the similarity factor f2 value of dissolution profile decreased in the order of HMESD > SESD > FCSD. HMESD exhibited a tendency of minimal changing on both dissolution behavior and spectral patterns. CONCLUSION: The combined strategy suggested the possibility for identification of specific SDs in quality control and prediction of their trends on the aging.
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Química Farmacêutica/métodos , Polietilenoglicóis/química , Polivinil/química , Povidona/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise por Conglomerados , Polietilenoglicóis/farmacocinética , Polivinil/farmacocinética , Povidona/farmacocinética , SolubilidadeRESUMO
OBJECTIVE: To evaluate the effects of the combination of basic fibroblast growth factor (bFGF), transforming growth factor-Β1 (TGF-Β1), bone marrow mesenchymal stem cells (BMSCs), and temperature-responsive chitosan hydrogel (TCH) gel on the repair of degenerative intervertebral disc in rat models. METHODS: Rat models of intervertebral disc degeneration were established by acupuncture. The degenerative effects were observed under magnetic resonance imaging (MRI). The BMSCs was cultured in vitro and then transfected by adenovirus with enhanced green fluorescent protein to make it carry the gene of enhanced green fluorescent protein,which functioned as fluorescence labeling. The SD rat models of intervertebral disc degeneration were divided into four groups: group A, treated with the combination of bFGF, TGF-Β1,BMSCs,and TCH gel; group B, treated with the combination of BMSCs and TCH gel;group C, treated with the combination of bFGF,TGF-Β1, and TCH gel;and group D, treated with PBS buffer solution. After the corresponding reagents were injected into the degenerative intervertebral discs of each group, the rats were cultivated for another four weeks and then the repair effects of the intervertebral discs were observed under MRI. Furthermore,the intervertebral discs of each group were taken out and observed by HE and Masson staining. The nucleus pulposus was aspirated and the expressions of aggrecan,collagen 2,Sox-9,and collagen I of nucleus pulposus of each group were tested by reverse transcription polymerase chain reaction and Western blot. RESULTS: The transplanted BMSCs survived in the intervertebral disc and differentiated into nucleus pulposus-like cells. MRI showed that:the signal intensity of the nucleus pulposus of group A was much higher than that of the rest groups, the signal intensity of group B was higher than that of group C, and the signal intensity of group D was the lowest,in which the dura mater spinalis was in compression and the spinal cord changed in beaded shape. The differences of the Pfirrmann grading among the four groups had statistical significance (P<0.05). The results of the HE and Masson stains showed:the intervertebral disc of group A was well-structured,the quantity of nucleus pulposus cells was larger than that of the other three groups,and the boundary between the nucleus pulposus and the annulus fibrosus was clearly defined;the quantity of the nucleus pulposus cells of group B was larger than that of group C, and the broken annulus fibrosus was not observed in group B, while the broken annulus fibrosus could be observed in group C; and, the nucleus pulposus cells of group D were replaced by fibrous tissue. The results of the reverse transcription polymerase chain reaction and Western blot tests showed that,in terms of the expressions of aggrecan,collagen 2 and Sox-9,group A was the highest, followed by group B,group C,and group D (P<0.05); in terms of the expression of collagen 1,there was no obvious difference among these four groups (P>0.05). CONCLUSIONS: The transplanted BMSCs can survive in the degenerative intervertebral disc and differentiate into nucleus pulposus-like cells. The combination of bFGF, TGF-Β1, BMSCs,and TCH gel has obvious repair effect on the degenerative intervertebral discs. The effect of the combination of BMSCs and TCH gel on transplantation therapy of the degenerative intervertebral discs is better than that of the combination of bFGF, TGF-Β1 and TCH gel but worse than that of the combination of bFGF, TGF-Β1, BMSCs, and TCH gel.