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Objective: The objective of this study is to investigate the effects of emergency nursing interventions, specifically those based on the Pediatric Early Warning Score (PEWS), on children diagnosed with acute asthma, to promote the recovery of children with asthma and improve the quality of care for children with asthma. Methods: A total of 80 children, Acute asthma attacks under the age of 12, diagnosed with acute asthma and admitted to the Emergency Department of Hebei Children's Hospital between June 2018 and June 2019 were selected as participants for this study. They were randomly assigned to either the control group or the PEWS group. There was no significant statistical difference in age, gender, course of disease, and disease severity between the two groups of children. In the control group, children received standard emergency nursing interventions, while in the PEWS group, children received emergency nursing interventions based on the Pediatric Early Warning Score (PEWS). To evaluate the effectiveness of these interventions, several outcome measures were compared between the two groups. This included assessing the duration for symptoms to disappear, analyzing pulmonary function indicators and respiratory dynamics indicators, measuring scores from the Pediatric Asthma Quality of Life Questionnaire (PAQLQ), and evaluating nursing satisfaction. Results: Following the implementation of the nursing interventions, 1. The average cough disappearance time of children in the PEWS group was 1.97 days shorter than that in the control group, the average wheezing disappearance time was 0.97 days shorter, the average dyspnea disappearance time was 0.64 days shorter, and the average lung wheezing disappearance time was 1.19 days shorter, which indicated that emergency care based on PEWS shortened the duration of symptoms in children with asthma. 2. The average FEV1 of children in the PEWS group was 9.87% higher than the control group, the average FVC was 0.62L higher, the average PEF was 9.84% higher, the average V70 was 0.91% higher, the average V50 was 0.43% higher , and the average V25 was 0.37% higher, when compared with control group. These results indicates that emergency care based on PEWS enhances the lung function of children with asthma. 3. The average respiratory rate of children in the PEWS group was 8.05 times/min lower, and the average dynamic respiratory system compliance was 6.91 mL/cmH2O higher, than that in the control group, which indicated that emergency care based on PEWS improved respiratory dynamics indicators in children with asthma. 4. The average PAQLQ symptom dimension score of children in the PEWS group was 0.84 points higher, the average activity dimension score was 0.34 points higher, and the average emotional dimension score was 0.47 points higher when compared with the control group. This indicated that emergency care based on PEWS improves the quality of life of children with asthma. 5. The nursing satisfaction of children in the PEWS group was 95%, higher than 72.5% in the control group, indicating that emergency care based on PEWS improved the satisfaction of asthma children with the nursing process. Conclusion: The implementation of PEWS based emergency care in pediatric asthma patients has important clinical significance in promoting recovery and improving the quality of care for asthma patients. The implementation of emergency nursing interventions based on the Pediatric Early Warning Score (PEWS) for children with acute asthma has been found to be effective in promoting the recovery of their condition, enhancing their quality of life, and improving nursing satisfaction.
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The inherently dynamic and anisotropic microenvironment of cells imposes not only global and slow physical stimulations on cells but also acute and local perturbations. However, cell mechanical responses to transient subcellular physical signals remain unclear. In this study, acoustically activated targeted microbubbles were used to exert mechanical perturbations to single cells. The cellular contractile force was sensed by elastic micropillar arrays, while the pillar deformations were imaged using brightfield high-speed video microscopy at a frame rate of 1k frames per second for the first 10s and then confocal fluorescence microscopy. Cell mechanical responses are accompanied by cell membrane integrity changes. Both processes are determined by the perturbation strength generated by microbubble volumetric oscillations. The instantaneous cellular traction force relaxation exhibits two distinct patterns, correlated with two cell fates (survival or permanent damage). The mathematical modeling unveils that force-induced actomyosin disassembly leads to gradual traction force relaxation in the first few seconds. The perturbation may also influence the far end subcellular regions from the microbubbles and may propagate into connected cells with attenuations and delays. This study carefully characterizes the cell mechanical responses to local perturbations induced by ultrasound and microbubbles, advancing our understanding of the fundamentals of cell mechano-sensing, -responsiveness, and -transduction. STATEMENT OF SIGNIFICANCE: Subcellular physical perturbations commonly exist but haven't been fully explored yet. The subcellular perturbation generated by ultrasound and targeted microbubbles covers a wide range of strength, from mild, intermediate to intense, providing a broad biomedical relevance. With µm2 spatial sensing ability and up to 1ms temporal resolution, we present spatiotemporal details of the instantaneous cellular contractile force changes followed by attenuated and delayed global responses. The correlation between the cell mechanical responses and cell fates highlights the important role of the instantaneous mechanical responses in the entire cellular reactive processes. Supported by mathematical modeling, our work provides new insights into the dynamics and mechanisms of cell mechanics.
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Fenômenos Mecânicos , Microbolhas , Ultrassonografia , Membrana Celular , MicroscopiaRESUMO
Endotoxin lipopolysaccharide (LPS) is a harmful substance commonly found in various environments that causes lung fibrosis. Exposure to PM2.5 also increases the risk of respiratory diseases. Through sulfur-carbon bonds and the edge S effect, GOQDs were used to bind in single-layer molybdenum disulfide (SLMoS2) nanosheets to synthesize SLMoS2@GOQDs heterojunction structures. GOQDs doping greatly increased the water solubility and stabilized of SLMoS2. SLMoS2@GOQDs with catalase-like activity protected cells from ultrastructural and cytomembrane damage and apoptosis induced by LPS. Moreover, the doping of GOQDs enhanced the escape of SLMoS2@GOQDs from cellular uptake and suppressed the release of Mo ions. Nanosheet-cell interface interactions that were regulated by quantum dots supported these positive effects. Immunofluorescence analysis and cell imaging confirmed that the nanomaterial protected against cell injury by regulating the canonical Wnt/ß-catenin pathway and the secretion of relevant cytokines, such as interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). Moreover, SLMoS2@GOQDs also mitigated pneumonia caused by PM2.5 in vivo. Collectively, our findings not only provide a simple and effective approach to control lung diseases (caused by LPS or PM2.5), but also reveal the potential value of heterojunction materials in the fields of toxicology and human health, boosting the application of nanotechnology in the fields of ecotoxicology and environmental safety.
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Acute lung injury (ALI) is a life-threatening clinical condition associated with critically ill patients, and the construction of potential microRNA (miRNA) and messenger RNA (mRNA) regulatory networks will help to fully elucidate its underlying molecular mechanisms. First, we screened fifteen upregulated differentially expressed miRNAs (DE-miRNAs) and six downregulated DE-miRNAs from the Gene Expression Omnibus (GEO) database. Then, the predicted target genes of the upregulated and downregulated DE-miRNAs were identified from the miRNet database. Subsequently, differentially expressed mRNAs (DE-mRNAs) were identified from the GEO database and subjected to combined analysis with the predicted DE-miRNA target genes. Eleven target genes of the upregulated DE-miRNAs and one target gene of the downregulated DE-miRNAs were screened out. To further validate the prediction results, we randomly selected a dataset for subsequent analysis and found some accurate potential miRNA-mRNA regulatory axes, including mmu-mir-7b-5p-Gria1, mmu-mir-486a-5p-Shc4 and mmu-mir-486b-5p-Shc4 pairs. Finally, mir-7b and its target gene Gria1 and mir-486b and its target gene Shc4 were further validated in a bleomycin-induced ALI mouse model. We established a potential miRNA-mRNA regulatory network of ALI in mice, which may provide a basis for basic and clinical research on ALI and advance the available treatment options.
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Lesão Pulmonar Aguda/genética , Redes Reguladoras de Genes/genética , MicroRNAs/genética , RNA Mensageiro/genética , Animais , Modelos Animais de Doenças , Regulação para Baixo , Expressão Gênica/genética , Camundongos , MicroRNAs/metabolismo , RNA Mensageiro/metabolismo , Regulação para CimaRESUMO
OBJECTIVE: To explore the value of radiographic assessment of lung edema (RALE) score in evaluating the severity and prognosis of patients with acute respiratory distress syndrome (ARDS). METHODS: A retrospective study was conducted. Patients with ARDS admitted to the department of intensive care unit (ICU) of Affiliated Nantong Third Hospital of Nantong University from January 2016 to November 2020 were enrolled. Clinical data of those patients were collected, and two senior radiologists who did not know the outcome of the patients independently scored each chest radiograph, the mean value of which was taken as the RALE score. The patients were divided into death group and survival group according to the 28-day prognosis. The differences of the basic data, PaO2/FiO2, sequential organ failure assessment (SOFA) score, acute physiology and chronic health evaluation II (APACHE II) score and RALE score between groups were analyzed. ARDS patients were classified according to the Berlin standard and RALE scores were compared between groups. Then, the correlations between RALE score and PaO2/FiO2, SOFA score, APACHE II score were analyzed. The prognostic capacity of RALE score for 28-day prognosis of ARDS patients were analyzed by Kaplan-Meier survival curve. RESULTS: Of the 98 ARDS patients, 62 were included in the final analysis, 39 patients survived and 23 patients died. The 28-day mortality was 37.1%. Compared with the survival group, patients in the death group were older (years old: 72.83±12.21 vs. 64.44±14.68), had lower PaO2/FiO2 [mmHg (1 mmHg = 0.133 kPa): 122.66±48.32 vs. 150.26±50.40], and higher SOFA score and greater difference of RALE score between the third day and the first day after admission (D3-D1 RALE score) (SOFA score: 11.26±3.91 vs. 9.04±3.72, D3-D1 RALE score: 1.35±6.42 vs. -2.74±7.35), with statistically significant differences (all P < 0.05). However, there were no significant differences in gender, cause of ARDS, APACHE II score, and RALE scores on the first and the third day of admission (D1 RALE, D3 RALE) between the two groups. Among the 62 patients, there were 11 mild cases (17.7%), 36 moderate cases (58.1%), and 15 severe cases (24.2%). The D1 RALE score of patients with mild and moderate ARDS were lower than those of patients with severe ARDS (19.09±3.65, 22.58±6.79 vs. 27.07±5.23, both P < 0.05). Correlation analysis showed that D1 RALE score was negatively correlated with PaO2/FiO2 (r = -0.385, P = 0.002), and positively correlated with SOFA score and APACHE II score (r1 = 0.433, r2 = 0.442, both P < 0.001). Kaplan-Meier survival curve analysis showed that the 28-day survival rate of ARDS patients in D3-D1 RALE score ≥ -1 group was significantly higher than that in D3-D1 RALE score < -1 group (73.08% vs. 55.56%; log-rank test: χ2 = 3.979, P = 0.046). CONCLUSIONS: The RALE score is a simple and reliable non-invasive evaluation index, which can be used to evaluate the severity of ARDS patients. The difference of RALE score in early stage is helpful to identify ARDS patients with poor prognosis.
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Síndrome do Desconforto Respiratório , Berlim , Edema , Humanos , Unidades de Terapia Intensiva , Pulmão , Prognóstico , Curva ROC , Síndrome do Desconforto Respiratório/diagnóstico por imagem , Estudos RetrospectivosRESUMO
A 63-year-old man was admitted for acute left heart failure after doing farm work. He rapidly developed refractory cardiogenic shock due to a large left atrial myxoma which was found by bedside echocardiography. Venoarteriovenous extracorporeal membrane oxygenation (ECMO) was performed immediately, and the patient was transferred for further surgery with a good outcome. Therefore, timely echocardiographic evaluation and surgical removal of myxomas is recommended, and ECMO could be used as a bridge between the transfer and perioperative period.
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Procedimentos Cirúrgicos Cardíacos/métodos , Oxigenação por Membrana Extracorpórea/métodos , Neoplasias Cardíacas/complicações , Mixoma/complicações , Choque Cardiogênico/cirurgia , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Mixoma/diagnóstico , Mixoma/cirurgia , Período Perioperatório , Choque Cardiogênico/etiologiaRESUMO
OBJECTIVE: To investigate the risk factors of citrate accumulation in patients with liver failure treated with regional citrate anticoagulated continuous renal replacement therapy (RCA-CRRT). METHODS: The clinical data of liver failure patients with RCA-CRRT admitted to department of intensive care unit (ICU) of Nantong Third People's Hospital from January 2017 to June 2020 were retrospectively analyzed. The selected patients were divided into citrate accumulation group and control group according to whether there was citrate accumulation (serum total calcium/free calcium ratio ≥ 2.4) during CRRT. The age, acute physiology and chronic health evaluation II (APACHE II), mean arterial pressure (MAP), norepinephrine (NE) dose, blood lactic acid (Lac) concentration, liver function status, citrate dose, filter time and prognosis of the patients were compared between the two groups. Unconditional Logistic regression was used to analyze the risk factors for citrate accumulation. RESULTS: Among 48 patients with RCA-CRRT and liver failure, 20 patients had citrate accumulation (accumulation group), and a total of 96 CRRTs were performed; the remaining 28 patients did not have citrate accumulation (control group), a total of 106 CRRTs were performed. There were no significant differences in age and APACHE II score between the two groups. Compared with the control group, the MAP in the accumulation group was lower [mmHg (1 mmHg = 0.133 kPa): 66.9±13.6 vs. 86.4±8.3, P = 0.032], and the dosage of NE (µg/min: 16.3±8.4 vs. 5.9±2.8, P = 0.015) and lactic acid level (mmol/L: 4.89±1.45 vs. 2.98±0.87, P = 0.004) were higher, the damage of liver function was more serious [total bilirubin (TBil, µmol/L): 220.4±45.2 vs. 163.4±43.8, P = 0.012; Child-Pugh score: 12.0±2.5 vs. 8.8±1.4, P = 0.029; model for end-stage liver disease (MELD) score: 31.30±8.22 vs. 21.78±6.40, P = 0.041], hourly citric acid dosage (mmol/h: 27.4±6.9 vs. 19.3±4.9, P = 0.032) and total citric acid dosage (mmol: 3 393±809 vs. 1 819±502, P = 0.039) were higher. Although there were no significant differences in the length of ICU stay, total length of hospitalization stay and cost of hospitalization between the two groups, the 28-day mortality of the accumulation group was higher than that of the control group (60.0% vs. 28.6%, P = 0.039). Unconditional Logistic regression analysis showed that MAP [odds ratio (OR) = 2.901, 95% confidence interval (95%CI) was 0.921-19.493, P = 0.019], NE dosage (OR = 2.098, 95%CI was 1.923-12.342, P = 0.002), Lac level (OR = 5.201, 95%CI was 3.211-9.433, P = 0.012), Child-Pugh score (OR = 1.843, 95%CI was 0.437-7.420, P = 0.018), MELD score (OR = 3.012, 95%CI was 0.384-12.843, P = 0.031), hourly citric acid dosage (OR = 4.254, 95%CI was 1.734-11.839, P = 0.011) and total citric acid dosage (OR = 4.109, 95%CI was 1.283-18.343, P = 0.001) were risk factors for citrate accumulation. CONCLUSIONS: In patients with tissue hypoperfusion and severe liver function damage, citrate anticoagulation should be avoided or the dosage of citric acid should be reduced, in order to avoid citrate accumulation.
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Terapia de Substituição Renal Contínua , Doença Hepática Terminal , Anticoagulantes/uso terapêutico , Citratos , Ácido Cítrico , Humanos , Prognóstico , Terapia de Substituição Renal , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de DoençaRESUMO
BACKGROUND Little is known about the relationship between the site of infection, type of pathogen, and the occurrence of sepsis-associated liver dysfunction (SALD). This population study aimed to identify the sites and types of infection in SALD patients. MATERIAL AND METHODS We conducted a retrospective observational study using the Medical Information Mart for Intensive Care III. Patients with sepsis were divided into a SALD group and a control group. We evaluated the effect of the location of culture-positive specimens and the distribution of pathogens on the occurrence of SALD and then compared the clinical outcomes. RESULTS A total of 14 596 admissions were included, and the incidence of SALD was 11.96%. Positive bile culture (odds ratio [OR] 7.450, P<0.001), peritoneal fluid culture (OR 3.616, P<0.001), and blood culture (OR 1.957, P<0.001) were correlated with the occurrence of SALD. Infection with Enterococcus faecium (OR 3.065, P<0.001), Bacteroides fragilis (OR 2.061, P<0.001), Klebsiella oxytoca (OR 2.066, P<0.001), Enterobacter aerogenes (OR 1.92, P=0.001), and Aspergillus fumigatus (OR 2.144, P=0.001) were correlated with the occurrence of SALD. The Intensive Care Unit mortality and hospital mortality were higher in the SALD group than in the control group (24.7% vs 9.0%, P<0.001; 34.2% vs 13.8%, P<0.001, respectively). CONCLUSIONS SALD should be considered for patients with sepsis whose infection site is the biliary system, abdominal cavity, or blood and the pathogen is Enterococcus faecium, B. fragilis, K. oxytoca, Enterobacter aerogenes, or A. fumigatus. When SALD occurs in patients with sepsis, the above infection sites and pathogens should be considered first.
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Hepatopatias/etiologia , Hepatopatias/microbiologia , Sepse/complicações , Idoso , Infecções Bacterianas/complicações , Cuidados Críticos , Bases de Dados Factuais , Feminino , Mortalidade Hospitalar , Humanos , Incidência , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Sepse/fisiopatologiaRESUMO
The extensive use of graphene-family nanomaterials (GFNs) in biomedicine and other fields has intentionally or unintentionally resulted in their introduction into the blood circulation system, but the effects of the biotransformation of GFNs in blood plasma on their biocompatibility, organ targeting, drug delivery and antitumor ability remain unclear. The present work discovered that GFN sheets were degraded in human blood plasma to holey sheets and aromatic hydrocarbons. The carbon atoms connected with oxygen-containing groups in the planes of GFNs were the initial attack sites for active substances (e.g., OH and O2-) in blood plasma. Subsequently, CC/CC bonds were broken. The reaction rate depended strongly on the extent of oxidization of GFNs. The pristine GFNs caused secondary structure damage to proteins and disturbances of cellular metabolic pathways. In contrast, the biotransformed nanomaterials presented high biocompatibility and were located in and targeted different tissues from their pristine forms, which influenced specific organ targeting therapy. The biotransformed nanomaterials also exhibited higher efficiencies of drug delivery (drug release and location) and killing tumor cells in vitro and in vivo. These findings provide insights into the application of nanomaterials in human healthcare using biotransformed nanomaterials.
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Sistemas de Liberação de Medicamentos/métodos , Grafite/química , Nanoestruturas/química , Animais , Biodegradação Ambiental , Feminino , Fibroblastos/metabolismo , Humanos , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos ICR , Soroalbumina Bovina/químicaRESUMO
RATIONALE: Extensive thrombosis in the portal venous system caused by hypereosinophilic syndrome (HES) is rare, and there is no consensus on anticoagulant and thrombolytic treatments for arteriovenous thrombosis caused by HES. PATIENT CONCERNS: The clinical data of a patient with extensive thrombosis in his portal venous system (superior mesenteric, splenic, hepatic, and portal veins), renal artery thrombosis, and mesenteric thrombosis caused by HES with secondary gastrointestinal bleeding and intestinal necrosis were retrospectively analyzed. Before admission, his eosinophil count increased to 7.47â×â10/L, and HES had been confirmed via bone marrow cytology. The patient experienced fever, cough, abdominal pain, massive hematemesis, and hematochezia that developed in succession. Abdominal computed tomography showed portal vein and superior mesenteric vein thromboses. DIAGNOSIS: Hypereosinophilic syndrome; extensive thrombosis in the portal venous system; acute eosinophil-associated pneumonia; gastrointestinal bleeding; intestinal necrosis. INTERVENTIONS: The patient was first treated with methylprednisolone, plasma exchange/hemofiltration, and single or combined use of unfractionated heparin and argatroban for anticoagulation. He was also administered alteplase and urokinase, successively, for thrombolytic treatment. Once the thromboses finally disappeared, the patient underwent surgery to excise a necrotic intestinal canal. OUTCOMES: The thromboses disappeared with these treatments, and the patient recovered after the necrotic intestinal canal was excised. LESSONS: The clinical manifestations of HES are complex and varied, and this condition can cause severe and extensive arteriovenous thrombosis. Anticoagulation therapy and thrombolysis are necessary interventions, and appear to be safe and effective.
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Síndrome Hipereosinofílica/complicações , Sistema Porta , Trombose Venosa/etiologia , Arginina/análogos & derivados , Estado Terminal , Quimioterapia Combinada , Fibrinolíticos/administração & dosagem , Hemorragia Gastrointestinal/etiologia , Heparina/administração & dosagem , Humanos , Síndrome Hipereosinofílica/diagnóstico , Síndrome Hipereosinofílica/fisiopatologia , Síndrome Hipereosinofílica/terapia , Masculino , Ácidos Pipecólicos/administração & dosagem , Troca Plasmática , Inibidores da Agregação Plaquetária/administração & dosagem , Eosinofilia Pulmonar/etiologia , Sulfonamidas , Ativador de Plasminogênio Tecidual/administração & dosagem , Tomografia Computadorizada por Raios X , Ativador de Plasminogênio Tipo Uroquinase/administração & dosagem , Trombose Venosa/diagnóstico por imagem , Adulto JovemRESUMO
BACKGROUND: This study was designed to evaluate the efficacy of exchange transfusion in patients with severe imported falciparum malaria. Twelve patients who met the diagnostic criteria for severe malaria were treated with exchange transfusion 14 times according to a conventional anti-malarial treatment. This study evaluated the efficacy of exchange transfusion for severe imported falciparum malaria. METHODS: Clinical data of severe imported falciparum malaria patients admitted to the intensive care unit (ICU) of Nantong Third People's Hospital from January 2007 to December 2016 were investigated in this retrospective study. Patients were divided into the intervention group, which received exchange transfusion, and the control group. This study assessed parasite clearance and outcomes of the two groups, and levels of erythrocytes, haemoglobin, platelets, coagulation, liver function, lactate, C-reactive protein, and procalcitonin, before and after exchange transfusion in the intervention group. RESULTS: There was no significant difference in the severity of admitted patients. Exchange transfusion was successfully applied 14 times in the intervention group. Differences in the levels of erythrocytes, haemoglobin and platelets did not reach statistical significance. Exchange transfusion improved coagulation, liver function, lactic acid, C-reactive protein, and procalcitonin. No differences were observed in parasite clearance, ICU and hospital length of stay, in-hospital mortality, and costs of hospitalization between the two groups. CONCLUSION: Exchange transfusion as adjunctive therapy for severe malaria was observed to be safe in this setting. Exchange transfusion can improve liver function and coagulation and reduce inflammation, but it failed to improve parasite clearance and the outcomes of severe imported falciparum malaria in this case series.
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Controle de Doenças Transmissíveis/métodos , Doenças Transmissíveis Importadas/prevenção & controle , Transfusão Total/estatística & dados numéricos , Malária Falciparum/prevenção & controle , Adulto , China , Doenças Transmissíveis Importadas/parasitologia , Humanos , Malária Falciparum/parasitologia , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Baicalin (BAI) has been reported to exert antitumor effects. However, BAI has limited water solubility, non-specific tumor targeting, and low bioavailability, which severely limited its clinical application. The aim of this study was to develop folic acid (FA) covalently conjugated-polyamidoamine (PAMAM) dendrimers (PAMAM-FA) as carrier systems for improvement of water solubility and tumor-specificity of BAI, and study the role of generation on the physiochemical properties and biological effects of PAMAM-FA/BAI complexes. In this work, four generations of PAMAM-FA were synthesized to entrap BAI. The average sizes of G3-FA/BAI, G4-FA/BAI, G5-FA/BAI, and G6-FA/BAI complexes were 174.4nm, 184.5nm, 258.8nm, and 247.5nm, respectively, and the zeta potentials of four PAMAM-FA/BAI complexes were -2.9mV, -6.6mV, -9.3mV, -9.0mV, respectively. The entrapment efficiencies of four PAMAM-FA/BAI complexes were 91.1%, 53.5%, 80.3%, and 91.9%, respectively, and the drug loading of PAMAM-FA/BAI complexes were about 22%. The formed PAMAM-FA/BAI complexes allowed sustained release of BAI in acidic PBS (pH5.4). In cellular uptake assay, PAMAM-FA/BAI complexes demonstrated increased drug uptake level in folate receptor (FR)-positive Hela cancer cells than FR-negative A549 cells, and the cellular uptake efficiency of PAMAM-FA is closely related with the generation of PAMAM. The MTT assay results showed that PAMAM-FA/BAI complexes demonstrated enhanced toxicity against Hela cells than non-FA-modified PAMAM/BAI complexes, and the G6-FA/BAI demonstrated the best inhibition efficiency. The cell cycle and cell apoptosis analysis further demonstrated the tumor-specific therapeutic efficacy of PAMAM-FA/BAI. These results suggested that the PAMAM-FA have the potential for targeted delivery of BAI into cancer cells to enhance its anti-tumor efficacy.
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Dendrímeros , Sistemas de Liberação de Medicamentos/métodos , Flavonoides , Ácido Fólico , Neoplasias/tratamento farmacológico , Poliaminas , Células A549 , Dendrímeros/química , Dendrímeros/farmacocinética , Dendrímeros/farmacologia , Flavonoides/química , Flavonoides/farmacocinética , Flavonoides/farmacologia , Ácido Fólico/química , Ácido Fólico/farmacocinética , Ácido Fólico/farmacologia , Células HeLa , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Poliaminas/química , Poliaminas/farmacocinética , Poliaminas/farmacologiaRESUMO
During the micro-drilling process of stainless steel, the wear, fracture, and breakage of the micro-drill easily occur. Micro-drill geometry parameters have significant influence on the drilling performance of the micro-drill. Nowadays, the helical point micro-drill is proposed and its improved drilling performance is validated by some researchers. In this study, to analyze the effect of geometry parameters of the helical point micro-drill on drilling performance, the mathematical models of the helical flank and ground flute are proposed, and the cutting lip shape, rake angle, and uncut chip thickness are calculated using MATLAB software. Then, based on the orthogonal tests, nine kinds of micro-drills with different point angles, web thicknesses, and helix angles are fabricated using a six-axis CNC tool grinder, and micro-drilling experiments on 1Cr18Ni9Ti stainless steel are carried out. The drilling force, the burr height, and the hole wall quality are measured and observed. The results show that the point angle is the main contributing factor for the thrust force and burr height, and the web thickness is the main contributing factor for the micro hole wall quality. The increased point angle offers a larger thrust force, but gives rise to a smaller exit burr. A larger web thickness leads to a larger thrust force and burr height, and results in a poor surface quality. With the helix angle increased, the thrust force and burr height decreases, and the surface quality of micro-hole improves. The geometry parameters with a point angle 70°, a point angle of 40°, and web thickness ratio of 0.2 can used to improve the drilling performance of the helical point micro-drill.
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Soil respiration (Rs) is a major source of carbon emission in terrestrial ecosystems. Despite the fact that the influence of land use practice on Rs has been widely studied, the patterns and drivers on Rs of Citrus reticulata cultivation, a worldwide land use practice are unclear. In this current study, we investigated the influence of long-term cultivation of Citrus reticulata (CO) and of CO intercropped with soybean (CB) on soil nutrients, water availability, and Rs in southern China. Results indicated that after 21 years of cultivation, CO and CB significantly increased total soil carbon (TC), total soil nitrogen (TN), and soil organic matter (OM) at 0-20 cm and 20-40 cm, both at upslope and downslope compared with bare soil (CK). However, soil moisture (SM), dissolved organic carbon (DOC), and microbial biomass carbon (MBC) decreased under CB. In addition, no significant variation was found in soil pH between CK, CO, and CB. Across incubation time (56 days), Rs decreased exponentially with incubation time and CB showed the highest Rs rate irrespective of soil depth or topography. Linear regression further showed TC and TN as the two major factors influencing Rs upslope, while DOC was the dominant factor in regulating Rs downslope. These findings demonstrated that long-term cultivation of citrus significantly changed soil nutrients, water availability, and Rs rate.
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Citrus/crescimento & desenvolvimento , Glycine max/crescimento & desenvolvimento , Solo/química , Biomassa , Carbono/análise , China , Produtos Agrícolas/crescimento & desenvolvimento , Nitrogênio/análiseRESUMO
Using the newly discovered borospherenes C3 B39(-) and C2 B39(-) as molecular devices and based on extensive global-minimum searches and first-principles calculations, we present herein the possibility of the first axially chiral metalloborospherenes C3 Ca@B39(+) (, (1)A) and C2 Ca@B39(+) (, (1)A), which are the global minimum and the second lowest-lying isomer of CaB39(+), respectively. These metalloborospherene species turn out to be charge-transfer complexes Ca(2+)@B39(-) in nature, with the Ca centre on the C3 or C2 molecular axis donating one electron to the B39 cage which behaves like a superhalogen. Molecular orbital analyses indicate that C3/C2 Ca(2+)@B39(-) possess the universal bonding pattern of σ plus π double delocalization, similar to their C3/C2 B39(-) parents. Molecular dynamics simulations show that both C3 Ca@B39(+) () and C2 Ca@B39(+) () are dynamically stable at 200 K, with the former starting to fluctuate structurally at 300 K and the latter at 400 K, again similar to C3/C2 B39(-). The infrared and Raman spectra of C3/C2 Ca@B39(+) (/) are simulated and compared with those of C3/C2 B39(-) to facilitate their forthcoming experimental characterization.
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The newly discovered borospherenes B40 (-/0) and B39 (-) mark the onset of a new class of boron nanostructures. Based on extensive first-principles calculations, we introduce herein two new chiral members to the borospherene family: the cage-like C1 B41 (+) (1) and C2 B42 (2+) (2), both of which are the global minima of the systems with degenerate enantiomers. These chiral borospherene cations are composed of twelve interwoven boron double chains with six hexagonal and heptagonal faces and may be viewed as the cuborenes analogous to cubane (C8 H8 ). Chemical bonding analyses show that there exists a three-center two-electron σâ bond on each B3 triangle and twelve multicenter two-electron πâ bonds over the σâ skeleton. Molecular dynamics simulations indicate that C1 B41 (+) (1) fluctuates above 300â K, whereas C2 B42 (2+) (2) remains dynamically stable. The infrared and Raman spectra of these borospherene cations are predicted to facilitate their experimental characterizations.
RESUMO
Chirality plays an important role in chemistry, biology, and materials science. The recent discovery of the B40(-/0) borospherenes marks the onset of a class of boron-based nanostructures. Here we report the observation of axially chiral borospherene in the B(39)(-) nanocluster on the bases of photoelectron spectroscopy, global minimum searches, and electronic structure calculations. Extensive structural searches in combination with density functional and CCSD(T) calculations show that B(39)(-) has a C3 cage global minimum with a close-lying C2 cage isomer. Both the C3 and C2 B(39)(-) cages are chiral with degenerate enantiomers. The C3 global minimum consists of three hexagons and three heptagons around the vertical C3 axis. The C2 isomer is built on two hexagons on the top and at the bottom of the cage with four heptagons around the waist. Both the C3 and C2 axially chiral isomers of B(39)(-) are present in the experiment and contribute to the observed photoelectron spectrum. The chiral borospherenes also exhibit three-dimensional aromaticity, featuring σ and π double delocalization for all valence electrons. Molecular dynamics simulations reveal that these chiral B(39)(-) cages are structurally fluxional above room temperature, compared to the highly robust D(2d)B40 borospherene. The current findings add chiral members to the borospherene family and indicate the structural diversity of boron-based nanomaterials.
Assuntos
Boro/química , Simulação de Dinâmica Molecular , Conformação Molecular , Nanoestruturas/química , Espectroscopia Fotoeletrônica , Teoria Quântica , Estereoisomerismo , TermodinâmicaRESUMO
The discovery of complementary methods for enantioselective transition metal-catalyzed cyclization with silyloxyenynes has been accomplished using chiral phosphine ligands. Under palladium catalysis, 1,6-silyloxyenynes bearing a terminal alkyne led to the desired five-membered ring with high enantioselectivities (up to 91% ee). As for reactions under cationic gold catalysis, 1,6- and 1,5-silyloxyenynes bearing an internal alkyne furnished the chiral cyclopentane derivatives with excellent enantiomeric excess (up to 94% ee). Modification of the substrate by incorporating an α,ß-unsaturation led to the discovery of a tandem cyclization. Remarkably, using silyloxy-1,3-dien-7-ynes under gold catalysis conditions provided the bicyclic derivatives with excellent diastereo- and enantioselectivities (up to >20:1 dr and 99% ee).
Assuntos
Alcinos/química , Ouro/química , Compostos de Organossilício/química , Fosfinas/química , Cátions/química , Ciclização , Estrutura Molecular , EstereoisomerismoRESUMO
OBJECTIVE: To investigate whether pituitrin can lower 28-day mortality as compared with treatment with norepinephrine (NE) in patients with septic shock. METHODS: Randomized, controlled, open-label trial was conducted. One hundred and thirty-nine septic shock patients with dopamine requirements exceeding 5 µg×kg(-1)×min(-1) were divided at random into two groups as the study group and control group. All patients enrolled were treated by the same treatment principle and measures. In patients of study group injection of pituitrin 0.017-0.042 U/min (1.0- 2.5 U/h) was given, and if hemodynamics was still unstable, catecholamines was added to obtain the target blood pressure; while in the control group catecholamines was given to maintain stability of hemodynamics. RESULTS: Among 139 patients enrolled in the study, 66 composed of the clinical study group and 73 in the control group. The main principle of the treatment in the two groups was similar. There was no significant difference in overall 28-day mortality rate between study group and control group (40.9% vs. 46.6%, P > 0.05). In patients whose acute physiology and chronic health evaluation II ( APACHE II ) score was less than 25, the mortality of study group was significantly lower than that of control group [10.3% (3/29) vs. 35.7% (10/28), P < 0.05]. The length of stay in intensive care unit [ICU, days: 5(3,8) vs. 5(3,8)], and duration of mechanical ventilation [days: 4.0 (2.8, 6.0) vs. 4.0 (2.0, 5.0)] were similar in two groups (both P > 0.05). The dosage of NE (µg/min: 7.99 ± 5.02 vs. 10.12 ± 5.12) and heart rate (beat/min: 93.27 ± 7.84 vs. 108.45 ± 12.31) were significantly lower in study group compared with that of control group (both P < 0.05). Serum creatinine and lactate levels in the two groups were similar at baseline, and creatinine [µmol/L: 87.5 (62.8, 157.0) vs. 76.0 (52.5, 117.0)] and lactate level (mmol/L: 3.72 ± 2.47 vs. 3.53 ± 1.86) were still similar in two groups 24 hours later (all P > 0.05). The rate of use of glucocorticoid (43.9% vs. 31.5%) and heparin in small dosage (42.4% vs. 41.1%) had no significant difference between two groups (both P > 0.05). CONCLUSIONS: Combined use of pituitrin in patients with septic shock can reduce the dosage of catecholamines, and decrease the heart rate. Although it can not lower the overall mortality of septic shock, among patients with less severity whose APACHE II score lower than 25, low-dose pituitrin in conjunction with catecholamine vasopressors can reduce 28-day mortality .
Assuntos
Hormônios Neuro-Hipofisários/uso terapêutico , Choque Séptico/tratamento farmacológico , Choque Séptico/mortalidade , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Norepinefrina/uso terapêutico , Hormônios Neuro-Hipofisários/administração & dosagem , Estudos Prospectivos , Taxa de SobrevidaRESUMO
Asymmetric copper-catalyzed allylic substitution with methylmagnesium bromide is employed in combination with ring-closing olefin metathesis or ene-yne metathesis to achieve the synthesis of chiral, unsaturated nitrogen heterocycles. The resulting six- to eight-membered chiral heterocycles are accessible in high yields and with excellent enantioselectivities.