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BACKGROUND: The Ley antigen is a carbohydrate chain belonging to the ABH-Lewis blood group family. Ley has been reported to be present on red blood cells (RBCs) and granulocytes, but its distribution and function in platelets remain unknown. There are a variety of glycoproteins on platelets, which may carry the Ley antigen. This study aims to investigate the expression pattern and the function of Ley in human platelets. STUDY DESIGN AND METHODS: Flow cytometry, Western blot, and immunofluorescence assays were performed to determine Ley expression on human platelets. ADP (1.25-10 µM) and thrombin (0.05-1 IU/mL) were used to activate platelets in the presence or absence of prostaglandin E1 (PGE1) and the Ley expression was evaluated again by flow cytometry. Blockade was performed with an anti-Ley monoclonal antibody to verify the role of this epitope in platelet function. Finally, coimmunoprecipitation was performed to identify glycoproteins associated with Ley . RESULTS: Ley was expressed on human platelets independent of ABO blood type. Ley expression was decreased in a dose-dependent manner after activation with either ADP or thrombin, and this effect could be partially reversed by PGE1. Anti- Ley mAb treatment increased alpha-granule release and neutralized the inhibitory effect of the anti-CD61 antibody on platelet aggregation. In addition, Ley was proven to interact and colocalize with CD61. CONCLUSIONS: These results demonstrate nondifferential expression of Ley in platelets of different ABO blood types and suggest the involvement of Ley in platelet function, possibly via interaction with CD61.
Assuntos
Plaquetas/metabolismo , Regulação da Expressão Gênica , Integrina beta3/metabolismo , Antígenos do Grupo Sanguíneo de Lewis/biossíntese , Agregação Plaquetária , Citometria de Fluxo , HumanosRESUMO
Targeting mitochondrial biogenesis has become a potential therapeutic strategy in cancer due to their unique metabolic dependencies. In this study, we show that levofloxacin, a FDA-approved antibiotic, is an attractive candidate for breast cancer treatment. This is achieved by the inhibition of proliferation and induction of apoptosis in a panel of breast cancer cell lines while sparing normal breast cells. It also acts synergistically with conventional chemo drug in two independent in vivo breast xenograft mouse models. Importantly, levofloxacin inhibits mitochondrial biogenesis as shown by the decreased level of mitochondrial respiration, membrane potential and ATP. In addition, the anti-proliferative and pro-apoptotic effects of levofloxacin are reversed by acetyl-L-Carnitine (ALCAR, a mitochondrial fuel), confirming that levofloxacin's action in breast cancer cells is through inhibition of mitochondrial biogenesis. A consequence of mitochondrial biogenesis inhibition by levofloxacin in breast cancer cells is the deactivation of PI3K/Akt/mTOR and MAPK/ERK pathways. We further demonstrate that breast cancer cells have increased mitochondrial biogenesis than normal breast cells, and this explains their different sensitivity to levofloxacin. Our work suggest that levofloxacin is a useful addition to breast cancer treatment. Our work also establish the essential role of mitochondrial biogenesis on the activation of PI3K/Akt/mTOR and MAPK/ERK pathways in breast cancer cells.
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Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Reposicionamento de Medicamentos , Levofloxacino/farmacologia , Mitocôndrias/efeitos dos fármacos , Biogênese de Organelas , Animais , Antibacterianos/uso terapêutico , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/metabolismo , Sinergismo Farmacológico , Feminino , Fluoruracila/uso terapêutico , Humanos , Levofloxacino/uso terapêutico , Redes e Vias Metabólicas/efeitos dos fármacos , Camundongos SCID , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Autophagy plays an important role in the development of diabetic retinopathy (DR). Retinal pigment epithelial (RPE) cells are the main cells involved in DR, a process in which hyperglycemia plays a crucial role. This study was conducted to investigate the protective effect of autophagy against high glucose-induced inflammatory response in ARPE-19 cells and its underlying mechanism. In the present study we subjected ARPE-19 cells to high glucose stress and showed that ARPE-19 cells respond to high glucose with an increase in autophagy. 3-methyladenine (3-MA) inhibited occurrence of autophagy and it leaded to the accumulation of damaged-mitochondria-producing-ROS, and the activation of NLRP3 inflammasome, and subsequently, caused IL-1ß secretion.
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Autofagia/fisiologia , Proteínas de Transporte/metabolismo , Glucose/metabolismo , Inflamassomos/metabolismo , Interleucina-1beta/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico , Linhagem Celular , Humanos , Proteína 3 que Contém Domínio de Pirina da Família NLR , Epitélio Pigmentado da Retina/citologia , Epitélio Pigmentado da Retina/metabolismoRESUMO
BACKGROUND: CD36 is a multifunctional membrane receptor and is expressed in several cell lines. Individuals who lack platelet (PLT) CD36 are at risk for immunization against this antigen, leading to several clinical syndromes. This study aimed to investigate the frequency and molecular basis of CD36 deficiency in Shanghai. STUDY DESIGN AND METHODS: Whole blood samples were collected from healthy blood donors, and the PLTs and monocytes were analyzed using flow cytometry to determine CD36 deficiency type. After genomic DNA was extracted, Exons 3 to 14 of CD36 gene including a part of relevant flanking introns were amplified. Direct nucleotide sequencing and sequence alignment were performed. The samples that showed mutations were confirmed by clonal sequencing. RESULTS: Of the 1022 healthy blood donors analyzed, 22 individuals failed to express CD36 on PLTs; two of them expressed no CD36 on their monocytes either. These results demonstrated that the frequencies of Type I (lacking CD36 expression on PLTs and monocytes) and Type II (lacking CD36 expression on PLTs only) CD36 deficiency among the study population were 0.2 and 2.0%, respectively. Nucleotide sequencing analysis revealed nine different mutations including six mutations that were not yet reported. The most frequent mutations among the study population were 329-330delAC and 1228-1239delATTGTGCCTATT. CONCLUSION: The study findings have confirmed the fact that the frequency of CD36 deficiency in the Chinese population is slightly lower than that in other Asian countries. The identification of several new mutation types indicated the polymorphism of CD36 gene in the Shanghai population.
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Povo Asiático/genética , Transtornos Plaquetários/genética , Antígenos CD36/genética , Doenças Genéticas Inatas/genética , Adulto , Sequência de Aminoácidos , Autoanticorpos/sangue , Sequência de Bases , Transtornos Plaquetários/sangue , Transtornos Plaquetários/etnologia , Plaquetas/química , Antígenos CD36/deficiência , Antígenos CD36/imunologia , China/epidemiologia , Análise Mutacional de DNA , Éxons/genética , Feminino , Frequência do Gene , Doenças Genéticas Inatas/sangue , Doenças Genéticas Inatas/etnologia , Genótipo , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Monócitos/química , Fenótipo , RNA Mensageiro/genética , Análise de Sequência de DNA , Adulto JovemRESUMO
BACKGROUND: The formation of scar-like fibrous tissue in age-related macular degeneration (AMD) is associated with hypoxia. Under hypoxia, retinal pigment epithelial (RPE) cells can secret more transforming growth factor-ß2 (TGF-ß2), which is determined to induce epithelial-mesenchymal transition (EMT) at certain concentrations. Whether hypoxia can induce EMT by stimulating RPE cell line secrets TGF-ß2 or not remains unknown. To gain a better understanding of the signaling mechanisms of fibrosis in AMD under hypoxic conditions, we investigated EMT in retinal pigment epithelial (RPE) cells and the effect of TGF-ß2 and Snail in this process. METHODS: Human RPE cell line (ARPE-19) was incubated with 5 % O2 for different periods of time. The expression of N-cadherin, α-smooth muscle actin (α-SMA), TGF-ß2 , and Snail were determined by Western blot and real-time PCR. Cell proliferation was assessed by CCK8 kit. RNA interference was used for multi-gene silencing of TGF-ß2 and Snail genes. RESULTS: N-cadherin was decreased and mesenchymal cell marker α-SMA was increased after the ARPE-19 cell line was incubated with 5 % O2. Meanwhile, the proliferation capability of the cell line was increased. TGF-ß2 and Snail expression were increased in a time-dependent manner under hypoxia. After multi-silencing TGF-ß2 and Snail genes, N-cadherin was increased and α-SMA was reduced. Meanwhile, the proliferation of the cell line was suppressed. CONCLUSIONS: Under hypoxic conditions, RPE cells undergo EMT. Endogenic TGF-ß2 and Snail are involved in this process. Furthermore, knockdown of both TGF-ß2 and Snail inhibited EMT to a greater extent than knockdown of either gene individually.
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Transição Epitelial-Mesenquimal/fisiologia , Inativação Gênica/fisiologia , Hipóxia/metabolismo , Epitélio Pigmentado da Retina/citologia , Fatores de Transcrição/genética , Fator de Crescimento Transformador beta2/genética , Actinas/genética , Actinas/metabolismo , Antígenos CD/genética , Antígenos CD/metabolismo , Western Blotting , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular , Proliferação de Células , Humanos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Epitélio Pigmentado da Retina/metabolismo , Fatores de Transcrição da Família Snail , Fatores de Transcrição/metabolismo , Transfecção , Fator de Crescimento Transformador beta2/metabolismoRESUMO
The investigation of agents for the treatment of osteoporosis has been a long-standing effort. The Wnt pathway plays an important role in bone formation and regeneration, and expression of Wnt pathway inhibitors, Dickkopf-1 (DKK1), appears to be associated with changes in bone mass. Inactivation of DKK1 leads to substantially increased bone mass in genetically manipulated animals. DKK1-derived peptides (DDPs) were added to BMP2-stimulated MC3T3-E1 preosteoblastic cells in vitro to evaluate inhibitory activity of DDPs in MC3T3-E1 cell differentiation. Study was extended in vivo on old female mice to show whether or not inhibition of endogenous DKK1 biological activity using DDPs vaccination approach leads to increase of bone formation, bone density, and improvement of bone microstructure. We reported that synthetic DDPs were able to reduce alkaline phosphatase activity, prevent mineralization and inhibit the differentiation of MC3T3-E1 cells in vitro. Furthermore, vaccination with these DDPs in aged female mice 4 times for a total period of 22 weeks promoted bone mass and bone microstructure. 3D microCT and histomorphometric analysis showed that there were significant increase in bone mineral densities, improvement of bone microstructure and promotion of bone formation in the vaccinated mice, especially in the mice vaccinated with DDP-A and DDP-C. Histological and scanning electron microscopy image analysis also indicated that vaccination increased trabecular bone mass and significantly decreased fragmentation of bone fibers. Taken together, these preclinical results suggest that vaccination with DDPs represents a promising new therapeutic approach for the treatment of bone-related disorders, such as osteoporosis.
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Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Osteogênese/fisiologia , Osteoporose/prevenção & controle , Vacinas/farmacologia , Absorciometria de Fóton , Envelhecimento , Animais , Western Blotting , Modelos Animais de Doenças , Feminino , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Microscopia Eletrônica de Varredura , Osteoporose/metabolismo , Peptídeos/imunologia , Vacinação , Microtomografia por Raio-XRESUMO
BACKGROUND: The basic method of glaucoma diagnosis is visual field examination, however, in patients with high myopia, the diagnosis of glaucoma is difficult. AIM: To explore the value of optical coherence tomography (OCT) for measuring optic disc parameters and macular thickness as a screening tool for glaucoma in patients with high myopia. METHODS: Visual values (contrast sensitivity, color vision, and best-corrected visual acuity) in three groups, patients with high myopia in Group A, patients with high myopia and glaucoma in Group B, and patients with high myopia suspicious for glaucoma in Group C, were compared. Optic disc parameters, retinal nerve fiber layer (RNFL) thickness, and ganglion cell layer (GCC) thickness were measured using OCT technology and used to compare the peri-optic disc vascular density of the patients and generate receiver operator characteristic (ROC) test performance curves of the RNFL and GCC for high myopia and glaucoma. RESULTS: Of a total of 98 patients admitted to our hospital from May 2018 to March 2022, totaling 196 eyes in the study, 30 patients with 60 eyes were included in Group A, 33 patients with 66 eyes were included in Group B, and 35 patients with 70 eyes were included in Group C. Data were processed for Groups A and B to analyze the efficacy of RNFL and GCC measures in distinguishing high myopia from high myopia with glaucoma. The area under the ROC curve was greater than 0.7, indicating an acceptable diagnostic value. CONCLUSION: The value of OCT measurement of RNFL and GCC thickness in diagnosing glaucoma in patients with high myopia and suspected glaucoma is worthy of development for clinical use.
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INTRODUCTION: Rectal cancer is one of the top 10 cancers worldwide. Up to 80% of patients with rectal tumours have had sphincter-saving surgery, mainly due to the large expectation of anal preservation. However, patients tend to experience low anterior resection syndrome (LARS) after rectal resection, which is disordered bowel function that includes faecal incontinence, urgency, frequent defecation, constipation and evacuation difficulties. LARS, with an estimated prevalence of 41%, has been reported to substantially decrease the quality of life of patients. However, no comprehensive preventive strategies are currently available for LARS. This systematic review aims to synthesise evidence on the current LARS preventive strategies. METHODS AND ANALYSIS: This protocol is reported according to the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) checklist. Literature in PubMed (via Medline), Embase and the Cochrane Library from inception to July 2023 will be searched to identify articles relevant to preventive effectiveness against LARS. The Cochrane Collaboration's risk of bias tool for randomised controlled trials and the Newcastle-Ottawa Scale for clinical controlled trials, cohort studies and case-control studies will be used to assess the risk of bias. We will group the included studies by the type of LARS prevention strategy and present an overview of the main findings in the form of evidence mapping. A meta-analysis is planned if there is no substantial clinical heterogeneity between the included studies. The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) will be used to evaluate the quality of the evidence. ETHICS AND DISSEMINATION: Ethical approval is not needed for systematic review of published data. The findings will be published in a peer-reviewed journal and disseminated at scientific conferences. PROSPERO REGISTRATION NUMBER: CRD42023402886.
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Síndrome de Ressecção Anterior Baixa , Neoplasias Retais , Humanos , Neoplasias Retais/cirurgia , Complicações Pós-Operatórias/prevenção & controle , Qualidade de Vida , Revisões Sistemáticas como Assunto , Metanálise como AssuntoRESUMO
INTRODUCTION: Gastroesophageal reflux disease (GERD) is a highly prevalent gastrointestinal disorder that causes diverse esophageal and extraesophageal symptoms. Many clinical practice guidelines (CPGs) have been issued around the world to provide practical evidence regarding GERD management. However, some of the recommendations discussed in various CPGs are inconsistent across individual documents. OBJECTIVES: We aimed to summarize the evidence from CPGs on GERD and assess the consistency of the recommendations. PATIENTS AND METHODS: In this scoping review, we identified current CPGs on the clinical management of GERD, which were comprehensively searched for in electronic databases and on relevant scientific websites. The recommendations were extracted using the populationinterventioncomparison framework and were subsequently categorized into tables. RESULTS: Ultimately, 24 CPGs were identified. They included 86 recommendations, which were classified into 5 categories: definition, epidemiology, diagnosis, treatment, and complications. Among the identified recommendations, 68 were proposed in at least 2 CPGs, and they were assessed for the consistency of direction and strength. Overall, 32.4% of the recommendations (22/68) were consistent in direction and strength, whereas 60.3% (41/68) were consistent in direction but inconsistent in strength. Moreover, 7.4% (5/68) were inconsistent in direction. These referred to the relationship between GERD and tobacco consumption, Helicobacter pylori infection, diagnostic utility of the 2week proton pump inhibitor test, cessation of special food, and antireflux surgery for GERD with extraesophageal symptoms. CONCLUSIONS: Most CPG recommendations regarding GERD were consistent in direction, except for 5 discrepancies, for which further welldesigned, largescale research is required to explain the inconsistency.
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Refluxo Gastroesofágico , Infecções por Helicobacter , Helicobacter pylori , Humanos , Refluxo Gastroesofágico/diagnóstico , Refluxo Gastroesofágico/terapia , Refluxo Gastroesofágico/complicações , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/complicações , Inibidores da Bomba de Prótons , Guias de Prática Clínica como AssuntoRESUMO
OBJECTIVE: To establish quantitative surface plasmon resonance (SPR) assay for antibodies against human platelet antigen-1a (HPA-1a). METHODS: Recombinant protein was fixed on the chip surface by amino coupling method. SPR assay was used to detect the standard antibodies against HPA-1a at different conceatration. The optimal experimental parameters were determined, and standard curves were constructed with linear regression. Moreover, the sensitivity, specificity, accuracy and precision of the assay were evaluated. RESULTS: The quantitative SPR assay for HPA-1a antibodies was established. The determination ranges were 0-20 IU, with accuracy (recovery rate) was 97.75%-103.08%. The intra-assay precision [coefficients of variation (CV)] was 3.53%-4.29%, and the inter-assay precision (CV) was 2.08%-4.40%. For specificity test, several kinds of monoclonal and human antibodies against platelet membrane protein were tested and no positive result was observed. CONCLUSION: The established quantitative SPR assay for HPA-1a antibodies shows good sensitivity, specificity, accuracy and precision, and this rapid and simple method provides a new reference method for scientific research and clinical antibody detection.
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Antígenos de Plaquetas Humanas , Plaquetas , Humanos , Integrina beta3 , Isoanticorpos , Ressonância de Plasmônio de SuperfícieRESUMO
NUCB2¹â»8³ has been recently reported as an anorexigenic and anti-hyperglycemic peptide. Here we report that NUCB2¹â»8³ promotes osteogenesis. It was found after two months of once-a-day intravenous injection of NUCB2¹â»8³, bone mineral density of femora and lumbar vertebrae were increased in ovariectomized rats. NUCB2¹â»8³ also increased the alkaline phosphatase activity and promoted mineralization in mouse MC3T3-E1 preosteoblastic cell line. When either both Arg6° and Arg6³ or Ser7² were mutated to Ala, the pro-osteogenic activity was completely lost, indicating that these residues are structurally important for its biological function. Furthermore, it encumbered osteoclastic differentiation of RAW 264.7 macrophage. It also excluded any possibility of the effect caused by contaminants or experimental faults, and demonstrated that the pro-osteogenic activity observed was a specific effect of NUCB2¹â»8³ itself. These findings warranted that further studies on NUCB2¹â»8³ would be valuable for the treatment of bone metabolic diseases especially for osteoporosis.