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ABSTRACT: Objective: This study explores how permissive hypercapnia, a key aspect of lung-protective ventilation, impacts postoperative delirium in elderly patients following thoracic surgery. Methods: A single-center trial at The Second Hospital of Anhui Medical University involved 136 elderly patients undergoing thoracoscopic esophageal cancer resection. Randomly assigned to maintain PaCO 2 35-45 mm Hg (group N) or 46-55 mm Hg (group H). Primary outcome: postoperative delirium (POD) incidence 1-3 days post-surgery. Secondary endpoints included monitoring rSO 2 , cardiovascular parameters (MAP, HR), pH, OI, and respiratory parameters (VT, RR, Cdyn, PIP) at specific time points. Perioperative tests assessed CRP/ALB ratio (CAR) and systemic inflammatory index (SII). VAS scores were documented for 3 postoperative days. Results: Postoperatively, group H showed significantly lower POD incidence than group N (7.4% vs. 19.1%, P = 0.043). Group H exhibited higher PaCO 2 and rSO 2 during surgery ( P < 0.05). Patients in group H maintained better cardiovascular stability with higher blood pressure and lower heart rate on T2-4 ( P < 0.05). Respiratory parameters were more stable in group H with lower TV, RR, and PIP, and higher Cdyn during OLV ( P < 0.05). Group H had lower pH and higher OI at T2-4 ( P < 0.05). CRP and CAR levels rose less in group H on the first day and 1 week later ( P < 0.05). Conclusions: Maintaining PaCO 2 at 46-55 mm Hg reduces POD incidence, possibly by enhancing rSO 2 levels and stabilizing intraoperative respiration/circulation.
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Esofagectomía , Hipercapnia , Laparoscopía , Complicaciones Posoperatorias , Toracoscopía , Humanos , Masculino , Anciano , Femenino , Esofagectomía/efectos adversos , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/etiología , Laparoscopía/efectos adversos , Delirio/etiología , Delirio/sangre , Neoplasias Esofágicas/cirugíaRESUMEN
OBJECTIVE: The purpose of this study was to examine the feasibility of using a combination of diaphragmatic ultrasound and muscle relaxation monitoring in predicting adverse respiratory events after extubation among elderly patients in an anesthetic intensive care unit (AICU). METHODS: The study participants were 120 elderly patients who were in the AICU after laparoscopic radical resection for colorectal cancer. Based on whether there were critical respiratory events (CREs) after extubation, they were divided into the adverse event group and the non-adverse event group. We used logistic regression to identify factors influencing the occurrence of CREs post-extubation in elderly patients. Using the receiver operating characteristic (ROC) curve, we analyzed the value of each indicator in predicting CREs post-extubation. RESULTS: We included 109 patients in the final analysis. In the adverse event group (n = 19), the age, proportion of females, and proportion of preoperative respiratory diseases were higher than in the non-adverse event group (n = 90). The muscle relaxation value, quiet breathing diaphragmatic excursion during extubation (DE-QB), deep breathing diaphragmatic excursion during extubation (DE-DB), and deep breathing diaphragmatic thickening fraction during extubation (DTF-DB) of patients in the adverse event group were significantly lower than those in the non-adverse event group (P < 0.05). Using binary logistic regression analysis, we identified muscle relaxation value, DE-DB, and DTF-DB during extubation as significant predictors of CREs post-extubation in elderly patients (P < 0.05). The area under the curve (AUC) of the combination of the muscle relaxation value, DE-DB, and DTF-DB during extubation for predicting CREs after extubation in elderly patients was 0.949, which was higher than that of any single indicator. CONCLUSION: The combination of diaphragmatic ultrasound and muscle relaxation monitoring was more accurate in predicting CREs post-extubation among elderly patients in the AICU.
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Anestesia , Desconexión del Ventilador , Femenino , Humanos , Anciano , Extubación Traqueal/efectos adversos , Estudios Prospectivos , Valor Predictivo de las Pruebas , Ultrasonografía , Diafragma/diagnóstico por imagen , Unidades de Cuidados Intensivos , Respiración ArtificialRESUMEN
BACKGROUND: Benign lymphoepithelial cyst (BLEC) of the parotid gland is a rare benign embryonic-dysplastic cystic tumor in the anterolateral neck that occurs most commonly in human immunodeficiency virus (HIV)-positive adults and rarely in non-acquired immune deficiency syndrome patients. The main presentation is a slow-growing, painless mass, and secondary infection may cause acute inflammatory symptoms. CASE SUMMARY: A 44-year-old Chinese male patient presented with a 1-year history of a mass in the left side of the neck. On physical examination, a mass similar in size and shape to a quail egg was found in the left parotid gland. The mass was tough, without tenderness, and easily moveable. The results of HIV tests, including antibody and nucleic acid tests and CD4+ T cell examination, were negative. Imaging examination revealed a left parotid gland mass. The patient underwent surgical treatment, and BLEC was diagnosed based on postoperative pathology. After 2 years of follow-up, the patient survived well without related discomfort. CONCLUSION: The detailed characteristics of a BLEC in a patient without HIV infection contribute to an improved understanding of this rare disease.
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Objective: This study aimed to investigate the correlation between changes in regional cerebral oxygen saturation (rSO2) and postoperative delirium in older adults undergoing major abdominal surgery. Materials and methods: This prospective study enrolled older adults scheduled for elective major abdominal surgery at the Second Affiliated Hospital of Anhui Medical University from August 2021 to January 2022. The change in rSO2 from baseline was determined using the hypo-to-hypercapnic test. The main study outcome was the occurrence of postoperative delirium. Results: A total of 101 participants were included for analysis, of whom 16 (15.8%) developed postoperative delirium. Compared with non-delirium participants, the mean arterial pressure and heart rate were not significantly different in the postoperative delirium group at T0, T1, T2, T3, T4, and T6 (all Pinteraction > 0.05), but the delirium group had lower pH, lower PaO2, and higher lactate levels at T4, T5, and T6 (all Pinteraction < 0.05). rSO2 at T0, T1, T2, T3, T4, and T6 was 69.0 (63.2-75.2), 70.7 ± 7.3, 68.2 ± 7.5, 72.1 ± 8.0, 69.9 ± 7.8, 67.4 ± 7.2, and 71.7 ± 8.1, respectively. The postoperative change in rSO2 during the hypercapnia test (TΔrSO2%) was 6.62 (5.31-9.36). Multivariable analysis showed that the Cumulative Illness Rating Scale (odd ratio, OR = 1.89, 95% confidence interval, CI: 1.10-3.25, P = 0.021), preoperative albumin levels (OR = 0.67, 95% CI: 0.48-0.94, P = 0.022), rSO2 at T4 (OR = 0.61, 95% CI: 0.41-0.89, P = 0.010), and postoperative TΔrSO2% (OR = 0.80, 95% CI: 0.66-0.98, P = 0.028) were independently associated with postoperative delirium in older adults undergoing elective abdominal surgery. Conclusion: The rSO2 measured at T4 and postoperative TΔrSO2% were independently associated with postoperative delirium in older adults undergoing elective abdominal surgery.
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BACKGROUND: Postoperative delirium (POD) is a common phenomenon after spinal surgery. Intraoperative fluid management may affect POD. The aim of this study was to compare the effects of restrictive fluid therapy (RF) with those of goal-directed fluid therapy (GDT) on POD. METHODS: A total of 195 patients aged ≥ 50 years who underwent spinal surgery were randomly divided into two groups: the RF group and the GDT group. In group RF, a bolus of lactated Ringer's solution was administered at a dose of 5 mL·kg-1 before the induction of anesthesia, followed by a dose of 5 mL·kg-1·h-1 until the end of surgery. For patients in the GDT group, in addition to the initial administration of lactated Ringer's solution at 5 mL·kg-1, the subsequent fluid therapy was adjusted by using a continuous noninvasive arterial pressure (CNAP) monitoring system to maintain pulse pressure variation (PPV) ≤ 14%. The primary endpoint was the incidence of POD, assessed once daily with the Confusion Assessment Method-Chinese Reversion (CAM-CR) scale at 1-3 days postoperatively. The secondary endpoints were intraoperative fluid infusion volume, urine volume, mean arterial pressure (MAP), heart rate (HR), cardiac index (CI), regional cerebral oxygen saturation (rSO2) value, lactic acid value, and visual analog scale (VAS) pain score at 1-3 days after surgery. Moreover, postoperative complications and the length of hospital stay were recorded. RESULTS: The incidence of POD was lower in the GDT group than in the RF group (12.4% vs 4.1%; P = 0.035) in the first 3 days after spine surgery. Compared to group RF, group GDT exhibited a significantly increased volume of intraoperative lactated Ringer's solution [1500 (interquartile range: 1128 to 1775) mL vs 1000 (interquartile range: 765 to 1300) mL, P < 0.001] and urine volume [398 (interquartile range: 288 to 600) mL vs 300 (interquartile range: 200 to 530) mL, P = 0.012]. Intraoperative MAP, CI and rSO2 values were higher in the GDT group than in the RF group (P < 0.05). Moreover, the length of hospital stay [17.0 (14 to 20) days versus 14.5 (13 to 17.0) days, P = 0.001] was shorter in the GDT group than in the RF group. CONCLUSIONS: GDT reduced the incidence of POD in middle- and old-aged patients undergoing spinal surgery possibly by stabilizing perioperative hemodynamic and improving the supply and demand of oxygen. TRIAL REGISTRATION: ChiCTR2000032603 ; Registered on May 3, 2020.
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BACKGROUND: TEM8 is a cell membrane protein predominantly expressed in tumor endothelium, which serves as a receptor for the protective antigen (PA) of anthrax toxin. However, the physiological ligands for TEM8 remain unknown. RESULTS: Here we identified uPA as an interacting partner of TEM8. Binding of uPA stimulated the phosphorylation of TEM8 and augmented phosphorylation of EGFR and ERK1/2. Finally, TEM8-Fc, a recombinant fusion protein comprising the extracellular domain of human TEM8 linked to the Fc portion of human IgG1, efficiently abrogated the interaction between uPA and TEM8, blocked uPA-induced migration of HepG2 cells in vitro and inhibited the growth and metastasis of human MCF-7 xenografts in vivo. uPA, TEM8 and EGFR overexpression and ERK1/2 phosphorylation were found co-located on frozen cancer tissue sections. CONCLUSIONS: Taken together, our data provide evidence that TEM8 is a novel receptor for uPA, which may play a significant role in the regulation of tumor growth and metastasis.
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Receptores ErbB/metabolismo , Proteínas de Neoplasias/metabolismo , Receptores de Superficie Celular/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/metabolismo , Secuencia de Aminoácidos , Animales , Línea Celular , Proliferación Celular , Humanos , Cinética , Proteínas de Microfilamentos , Metástasis de la Neoplasia , Fosforilación , Dominios Proteicos , Receptores del Activador de Plasminógeno Tipo Uroquinasa/química , Receptores del Activador de Plasminógeno Tipo Uroquinasa/metabolismo , Activador de Plasminógeno de Tipo Uroquinasa/químicaRESUMEN
UNLABELLED: : Adipose-derived mesenchymal stem cells (AD-MSCs) have been shown to ameliorate hyperglycemia in diabetic animals and individuals. However, little is known about whether AD-MSCs affect lipid metabolism. Here we have demonstrated for the first time that AD-MSC infusion can significantly suppress the increase in body weight and remarkably improve dyslipidemia in db/db obese mice and diet-induced obesity mice. Induction of white fat tissue "browning" and activation of adenosine monophosphate-activated protein kinase and its downstream hormone-sensitive lipase in adipose tissue contribute to the antiobesity and lipid-lowering effects. Thus, AD-MSC infusion holds great therapeutic potential for dyslipidemia and associated cardiovascular diseases. SIGNIFICANCE: Mesenchymal stem cells (MSCs) are considered one of the most promising types of stem cells for translational application because of their rich tissue sources, multilineage differentiation capacity, and easy amplification in vitro and unique immunobiological properties. This study demonstrated that adipose-derived MSCs (AD-MSCs) infusion can significantly suppress the increase in body weight and remarkably improve dyslipidemia in obese mice. Induction of white fat tissue "browning" and activation of adenosine monophosphate-activated protein kinase and its downstream hormone-sensitive lipase in adipose tissue were demonstrated to contribute to the antiobesity and lipid-lowering effects. Thus, AD-MSC infusion holds great therapeutic potential for dyslipidemia.
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Tejido Adiposo/citología , Dislipidemias/metabolismo , Trasplante de Células Madre Mesenquimatosas , Proteínas Quinasas Activadas por AMP/metabolismo , Animales , Glucemia , Western Blotting , Modelos Animales de Enfermedad , Inmunohistoquímica , Lípidos/sangre , Masculino , Células Madre Mesenquimatosas , Ratones , Ratones Endogámicos C57BL , Ratones Obesos , Reacción en Cadena en Tiempo Real de la Polimerasa , Esterol Esterasa/metabolismoRESUMEN
OBJECTIVE: To study transfection efficiency of Ad5F11p-GFP and its influence on biological characteristics of CIK and NK-92 cells in order to predict the application of Ad5F11p vector in immunotherapy. METHODS: Two kinds of immune cells, cytokine-induced killer (CIK) cells and natural-killer (NK) cell line NK-92 cells, were transfected by Ad5F11p-GFP at different multiplicity of transfection (MOI), and untransfected immune cells were used as negative control. GFP expression was determined by flow cytometry, the cell morphology was observed with microscope, the cell proliferation was analyzed by trypan blue staining, specific cytotoxicity of NK-92 cells was determined by LDH assay. RESULTS: About 90% of transfection efficiency for NK-92 cells could be achieved at a MOI of 25, while the transfection efficiency for CIK was less than 40% at a MOI of 200. In addition, the transfection efficiency basically unchanged at the same MOI for 48 h and 96 h, and the immune cells transfected with the virus trended to form agglomeration, displaying slower proliferation, increase of IFN-γ release and enhancement of tumor killing activity. CONCLUSION: Ad5F11p- modified NK-92 shows a good prospect for adoptive immunotherapy.
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Células Asesinas Inducidas por Citocinas/citología , Citotoxicidad Inmunológica , Células Asesinas Naturales/citología , Transfección , Adenoviridae , Línea Celular , Proliferación Celular , Vectores Genéticos , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Inmunoterapia Adoptiva , Neoplasias/terapiaRESUMEN
BACKGROUND: Epidural anesthesia may attenuate the sympathetic hyperactivity and stress response from surgery. In this study, we compared the stress response, hemodynamic variables, and recovery profiles of patients undergoing total IV anesthesia (TIVA) and intraoperative dexmedetomidine with those receiving epidural anesthesia and TIVA. METHODS: Ninety patients undergoing elective open gastrectomy under TIVA were recruited. The dexmedetomidine group (group D, n = 30) received IV dexmedetomidine 0.6 µg/kg before the induction of general anesthesia, followed by dexmedetomidine 0.4 µg/kg/h until peritoneal closure. The control group (group C, n = 30) received volume-matched normal saline infusion as placebo. The epidural group (group E, n = 30) received epidural anesthesia with 0.375% ropivacaine combined with TIVA. The hemodynamic variables and recovery characteristics during emergence were evaluated. Blood samples for norepinephrine (NE), epinephrine (E), cortisol (Cor), and cytokines (tumor necrosis factor-α [TNF-α], interleukin [IL]-6, and IL-10) were obtained before the administration of dexmedetomidine or epidural anesthesia (baseline), immediately after tracheal intubation, upon incision, at the time of celiac exploration, and at tracheal extubation. RESULTS: Compared with group E, there were no differences in the plasma concentration levels of NE, E, Cor, and cytokines (TNF-α, IL-6, and IL-10) in group D at all time points. The levels of NE and E in groups D and E were significantly lower than that in group C, at all time points following induction (all P < 0.0001 except at incision which were P = 0.001 and P = 0.004), and the level of Cor in groups D and E was significantly lower than that in group C at celiac exploration (P = 0.017 and P = 0.019) and immediately after tracheal extubation (P < 0.0001). The levels of TNF-α, IL-6, and IL-10 increased after the celiac exploration in the 3 groups. The levels of plasma TNF-α, IL-6, and IL-6/IL-10 ratio were higher in group C than in groups D and E at celiac exploration and tracheal extubation (all P < 0.0001 except at celiac exploration which were P = 0.005 and P =0.038 for TNF-α and P = 0.049 and P = 0.038 for IL-6/IL-10 ratio). In group D, the heart rate was significantly slower after commencing dexmedetomidine and remained significantly slower throughout the operative course (all P < 0.0001 except at tracheal extubation which was P = 0.032). The number of patients who required intervention because of intraoperative hypotension was significantly higher in group E (36.7%) compared with groups D and C (13.3% and 10.0%) (P = 0.037, P = 0.015). The times to eye opening and tracheal extubation were similar in all groups. There were fewer incidences of agitation in group D (6.7 %) than in group C (26.6%) (P = 0.038). CONCLUSIONS: When used in conjunction with TIVA, intraoperative dexmedetomidine blunts surgical stress responses to an extent comparable to combined epidural and general anesthesia without compromising hemodynamic stability and with minimal adverse effects during the intraoperative period.
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Anestesia Epidural/métodos , Anestesia General/métodos , Dexmedetomidina/administración & dosificación , Hipnóticos y Sedantes/administración & dosificación , Complicaciones Intraoperatorias/prevención & control , Estrés Psicológico/prevención & control , Administración Intravenosa , Terapia Combinada/métodos , Femenino , Humanos , Cuidados Intraoperatorios/métodos , Complicaciones Intraoperatorias/sangre , Complicaciones Intraoperatorias/psicología , Masculino , Persona de Mediana Edad , Estrés Psicológico/sangre , Estrés Psicológico/psicologíaRESUMEN
Mesenchymal stem/stromal cells (MSCs) possess some characteristics of immune cells, including a pro-inflammatory phenotype, an immunosuppressive phenotype, antibacterial properties and the expression of Toll-like receptor proteins. Here we show that, similar to immune cells, MSCs retain information from danger signals or environmental stimuli for a period of time. When treated with the pro-inflammatory factors lipopolysaccharide (LPS) or tumor necrosis factor-α (TNF-α), MSCs display increased expression of IL-6, IL-8 and MCP-1. Following re-plating and several rounds of cell division in the absence of stimulating factors, the expression of IL-6, IL-8 and MCP-1 remained higher than in untreated cells for over 7 days. A spike in cytokine secretion occurred when cells were exposed to a second round of stimulation. We primed MSCs with LPS and LPS-primed MSCs had better therapeutic efficacy at promoting skin flap survival in a diabetic rat model than did unprimed MSCs. Finally, we found that several microRNAs, including miR146a, miR150 and miR155, along with the modification of DNA by 5-hydroxymethylcytosine (5hmC), mediate the MSC response to LPS and TNF-α stimulation. Collectively, our data suggest that MSCs have a short-term memory of environmental signals, which may impact their therapeutic potential.
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Memoria Inmunológica , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/metabolismo , Transducción de Señal , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Tejido Adiposo/citología , Animales , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Forma de la Célula/efectos de los fármacos , Quimiocina CCL2/metabolismo , Metilación de ADN/efectos de los fármacos , Diabetes Mellitus Experimental/patología , Ensayo de Inmunoadsorción Enzimática , Memoria Inmunológica/efectos de los fármacos , Inmunofenotipificación , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Lipopolisacáridos/farmacología , Masculino , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , MicroARNs/genética , MicroARNs/metabolismo , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa , Transducción de Señal/efectos de los fármacos , Colgajos Quirúrgicos/fisiología , Supervivencia Tisular/efectos de los fármacos , Factor de Necrosis Tumoral alfa/farmacologíaRESUMEN
Ribosomal protein S6 (rpS6) has long been regarded as one of the primary r-proteins that functions in the early stage of 40S subunit assembly, but its actual role is still obscure. The correct forming of 18S rRNA is a key step in the nuclear synthesis of 40S subunit. In this study, we demonstrate that rpS6 participates in the processing of 30S pre-rRNA to 18S rRNA only when its C-terminal five serines are phosphorylated, however, the process of entering the nucleus and then targeting the nucleolus does not dependent its phosphorylation. Remarkably, we also find that the aggregation of rpS6 at the nucleolus correlates to the phasing of cell cycle, beginning to concentrate in the nucleolus at later S phase and disaggregate at M phase. J. Cell. Biochem. 117: 1649-1657, 2016. © 2015 Wiley Periodicals, Inc.
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Nucléolo Celular/metabolismo , Agregado de Proteínas/fisiología , Precursores del ARN/metabolismo , Procesamiento Postranscripcional del ARN/fisiología , ARN Ribosómico 18S/metabolismo , Proteína S6 Ribosómica/metabolismo , División Celular/fisiología , Células HEK293 , Humanos , Fosforilación/fisiología , Fase S/fisiologíaRESUMEN
The epidermal growth factor receptor (EGFR) family belongs to type I receptor tyrosine kinases. Overexpression or mutation of EGFR/ErbB1 gene has been detected in a large number of human solid tumours. According to some previous report, this gene is not expressed in hematological malignancies. However, two recent clinical case reports showed that erlotinib caused complete remission of acute myeloid leukaemia (AML)-M1 in patients who had both AML-M1 and non-small-cell lung cancer. These results are supported by preclinical studies in which EGFR tyrosine kinase inhibitors have anti-proliferative effects on AML. These findings prompted us to determine whether EGFR is expressed in human AML, through a large-scale screening of both leukaemic cell lines and clinical samples. Our results show that EGFR is expressed by about 33% of human AML (containing M1 to M7 subtypes) and by some human leukaemia cell lines (K562, MEG-01, CEM and SKO-007). Its expression is not limited to certain AML types but has been detected in many leukaemic cells. In addition, EGFR expression was intimately associated with the poor clinical outcomes. Finally, we find that only EGFR-positive leukaemic cells respond to antibody-dependent cellular cytotoxicity of cetuximab, the monoclonal antibodies against EGFR.
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Receptores ErbB/análisis , Leucemia Mieloide Aguda/mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Citotoxicidad Celular Dependiente de Anticuerpos , Apoptosis , Línea Celular Tumoral , Movimiento Celular , Femenino , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Masculino , Persona de Mediana Edad , Pronóstico , Modelos de Riesgos ProporcionalesRESUMEN
Urokinase (uPA) and its receptor (uPAR) play an important role in tumor growth and metastasis, and overexpression of these molecules is strongly correlated with poor prognosis in a variety of malignant tumors. In this study, ATF-Fc, an antibody-like molecule comprising the amino-terminal fragment of human uPA (ATF) linked to the Fc fragment of human IgG1 via a flexible linker was developed. Its antitumor activities were evaluated in vitro and in vivo. The results showed that ATF-Fc had obvious cytotoxic effect on several types of tumor cells, which is dependent on cellular expression of uPAR and its Fc fragment. Treatment with ATF-Fc caused a significant suppression on tumor growth and metastasis of xenograft human tumors (MCF-7 breast cancer and BGC-823 gastric cancer) in athymic nude mice. Furthermore, we demonstrated that ATF-Fc had an anti-angiogenesis activity both in vitro and in vivo. In conclusion, we provided a novel therapeutic antibody-like molecule in the management of a variety of solid tumors by disrupting the uPA/uPAR interaction.
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Fragmentos Fc de Inmunoglobulinas/química , Neoplasias/terapia , Receptores de Superficie Celular/química , Activador de Plasminógeno de Tipo Uroquinasa/química , Secuencia de Aminoácidos , Animales , Anticuerpos/química , Línea Celular Tumoral , Matriz Extracelular/metabolismo , Humanos , Inmunoglobulina G/química , Ratones , Ratones Desnudos , Datos de Secuencia Molecular , Metástasis de la Neoplasia , Neovascularización Patológica , Receptores del Activador de Plasminógeno Tipo UroquinasaRESUMEN
Tumor endothelial marker 8 (TEM8) was discovered as a cell membrane protein that is predominantly expressed in tumor endothelium and identified as a receptor for anthrax toxin. We developed an antibody-like molecule that consists of the protective antigen (PA)-binding domain of human TEM8 linked to the Fc portion of human immunoglobulin G1 (TEM8-Fc). This engineered protein bound to PA in a divalent cation-dependent manner and efficiently protected J774A.1 macrophage-like cells against anthrax toxin challenge in a dose-dependent manner. TEM8-Fc suppressed the growth and metastasis of xenograft human tumors in athymic nude mice (control versus 10 mg/kg TEM8-Fc, mean tumor weight: LS-180, 1.72 versus 0.16 g, difference = 1.56 g, 95% confidence interval [CI] = 0.96 to 2.16 g; P<.001; MCF-7, 1.12 versus 0.08 g, difference = 1.04 g, 95% CI = 0.77 to 1.31 g; P<.001; HepG2, 1.28 versus 0.35 g, difference = 0.93 g, 95% CI = 0.60 to 1.25 g; P<.001). Furthermore, TEM8 interacted with the M2 isoenzyme of pyruvate kinase (M2-PK), which has an important role in tumor growth and metastasis. TEM8-Fc is a novel therapeutic antibody-like agent in the management of solid tumors that may act by trapping M2-PK.
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Antineoplásicos/farmacología , Fragmentos Fc de Inmunoglobulinas/farmacología , Inmunoglobulina G/farmacología , Proteínas de la Membrana/efectos de los fármacos , Proteínas de la Membrana/farmacología , Proteínas de Neoplasias/efectos de los fármacos , Piruvato Quinasa/efectos de los fármacos , Receptores de Superficie Celular/efectos de los fármacos , Animales , Anticuerpos , Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral , Neoplasias del Colon/tratamiento farmacológico , Diseño de Fármacos , Femenino , Humanos , Inmunoprecipitación , Neoplasias Hepáticas/tratamiento farmacológico , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Ratones Desnudos , Proteínas de Microfilamentos , Proteínas de Neoplasias/metabolismo , Receptores de Superficie Celular/metabolismo , Proteínas Recombinantes de Fusión/farmacología , Trasplante HeterólogoRESUMEN
The binding of Sulfonylurea herbicides to catalase in aqueous solution was studied using fluorescence spectroscopy. It was shown that herbicides have a strong ability to quench the catalase fluorescence mainly through a static quenching procedure. The binding constant K and the number of binding site n were calculated according to the fluorescence quenching results. For chlorsufuron, K=8.69 x 10(5) L x mol(-1) and n = 1.16; for metsufuron methyl, K = 1.01 x 10(6) L x mol(-1) and n = 1.21; and for bensufuron methyl, K = 3.52 x 10(3) L x mol(-1), n = 0.77. It is clear that the binding of metsufuron methyl with catalase is stronger than that of chlorsufuron, while the binding of chlorsufuron stronger than that of bensufuron methyl.
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Catalasa/química , Herbicidas/química , Espectrometría de Fluorescencia , Compuestos de Sulfonilurea/química , Algoritmos , Arilsulfonatos/química , Arilsulfonatos/metabolismo , Sitios de Unión , Unión Competitiva , Catalasa/metabolismo , Fluorescencia , Herbicidas/metabolismo , Cinética , Unión Proteica , Compuestos de Sulfonilurea/metabolismoRESUMEN
ATR-Fc is a fusion protein consisting of extracellular domain of human anthrax toxin receptor (ATR) and a fragment (hinge, CH2, and CH3 domains) of the Fc of human IgG1. The aim of ATR-Fc expression is to get an antibody-like molecule binding to protective antigen (PA), a component of anthrax toxins, this fusion protein may compete with cell surface receptor for PA binding, and block the transport of lethal factor (LF) and edema factor (EF) into cells, thereby act as an antitoxin to prevent and treat anthrax infection. A DNA fragment encoding N-terminal amino acids 1-227 of ATR and human IgG1 Fc was inserted into the Hind III and Not I sites of pcDNA3.1 to generate the eukaryotic vector pcDNA3.1/ATR-Fc for expression of ATR-Fc fusion protein. Using lipofectine-mediated gene transfer technique, pcDNA3.1/ATR-Fc was transfected into CHO-K1 cells. After selected with G418, a recombinant CHO cell line, ATR-Fc-1D5, whose expression level was about 10 - 15 microg/(10(6) cells x d), was established. The recombinant protein expressed by the ATR-Fc-1D5 cells was purified with protein A chromatography. The experimental results demonstrated a direct and specific interaction between ATR-Fc and PA assessed by ELISA.
Asunto(s)
Fragmentos Fc de Inmunoglobulinas/genética , Inmunoglobulina G/genética , Proteínas de Neoplasias/genética , Receptores de Superficie Celular/genética , Proteínas Recombinantes de Fusión/biosíntesis , Animales , Células CHO , Cricetinae , Cricetulus , Técnicas de Transferencia de Gen , Vectores Genéticos , Humanos , Fragmentos Fc de Inmunoglobulinas/biosíntesis , Inmunoglobulina G/biosíntesis , Proteínas de Microfilamentos , Proteínas de Neoplasias/biosíntesis , Receptores de Superficie Celular/biosíntesis , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunologíaRESUMEN
The only difference of primary structure between single-chain prourokinase (pro-UK or scu-PA) and two-chain urokinase (UK or tcu-PA) is the cleavage of a single peptide bond (Lys158-Ile159) and transform scu-PA into its active two-chain form. A 13-peptide (Thr-Leu-Arg-Pro-Arg-Phe-Lys-Ile-Ile-Gly-Gly-Glu-Cys), which spans the cleavage peptide bond, was synthesized and linked to KLH (Keyhole limpet hemocyanin). The Balb/c mice were immunized by the conjugated protein with proper adjuvant. According to the Kohler and Milstein's methods, a hybridoma cell line G7 secreting monoclonal antibody specific for scu-PA was obtained. The anti-scu-PA McAb, purified from the supernatant of porous microcarrier hybridoma cell culture, was conjugated to CNBr-activated Sepharose 4B to prepare an immuno-affinity chromatography column. The u-PA was purified only by this affinity column from the supernatant of cultivating the u-PA-producing recombinant CHO cell, the u-PA recovery ratio is 90.4%, the purification factor was about 50, with the specific activity of 1.2 x 10(5) IU/mg, the scu-PA ratio in the u-PA product was 96.3%. Compared to immuno-affinity chromatography, the 3-step process for purifying u-PA (cation-exchange column, gel filtration column and benzamidine affinity column) has a u-PA recovery ratio of about 65%, with a specific activity of 1.0 x 10(5) IU/mg, and an scu-PA ratio of about 90%. These results showed that immuno-affinity chromatography is simple to recover u-PA and effective to separate scu-PA from tcu-PA.