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1.
Artículo en Inglés | MEDLINE | ID: mdl-38551435

RESUMEN

Objective: To assess the effectiveness of perioperative nursing interventions in improving outcomes and satisfaction for patients undergoing laparoscopic surgery for ovarian endometriosis. Methods: From July 2021 to September 2022, 80 patients with endometriosis underwent laparoscopic surgery at Shijiazhuang Fourth Hospital and were randomly assigned to the conventional (n=40) and experimental (n=40) groups. During the perioperative period, patients in the conventional group received standard nursing interventions, while patients in the experimental group received comprehensive nursing interventions. The two groups were compared in terms of postoperative clinical indicators, self-rated anxiety scale (SAS) and self-rated depression scale (SDS) scores, nursing compliance, complications, and nursing satisfaction. Results: comprehensive nursing resulted in better postoperative clinical indices (time to get out of bed, hospital stay) versus routine nursing (all P < .001). The comprehensive nursing led to significantly lower SAS and SDS scores versus routine nursing. The nursing compliance of the patients in the experimental group was significantly higher than that of the patients in the conventional group (P < .001). Comprehensive nursing was associated with a significantly lower incidence of complications versus routine nursing (P < .001). Comprehensive nursing contributed to significantly higher nursing satisfaction versus routine nursing (P < .001). Conclusion: Comprehensive perioperative nursing interventions for patients with ovarian endometriosis undergoing laparoscopic surgery considerably accelerate patient recovery and enhance nursing compliance, as well as minimize patient negative emotions and improve patient satisfaction with nursing.  The comprehensive approach addresses the specific needs of patients during the recovery period, minimizing postoperative complications, accelerating patient recovery, and improving overall quality of life. By integrating psychological support, tailored strategies for pain management, early mobilization, and prompt intervention for complications, this intervention sets a benchmark for holistic care in gynecological surgery.

2.
J Sci Food Agric ; 103(14): 6912-6919, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37319235

RESUMEN

BACKGROUND: Citrus residuals are rich in nutrients like pectin, essential oil, and amino acids, which are wasted in the food industry. Moreover, citrus components often coexist with amino acids during emulsion preparation and application. RESULTS: Adding glutamic or arginine after emulsification resulted in a stable emulsion compared with adding them before emulsification. Adding glycine before or after emulsification had no effect on the emulsion stability. Emulsion stability was improved by adding glutamic acid at pH 6. Ionic interaction and hydrogen bonding were the main forms of bonding. The rhamnogalacturonan II domain was the potential binding site for the amino acids. CONCLUSIONS: The emulsions prepared by adding acidic amino acids or basic amino acids after emulsification were stable relative to those in which the amino acids were added before emulsification. However, the order in which neutral amino acids were added did not affect the emulsion stability after storage for 7 days. With an increase in the pH level, droplet size increased and emulsion stability decreased. All the results could be attributed to changes in the structure and properties of citrus pectin, as well as the interaction between citrus pectin and amino acids. This study may expand the application of citrus-derived emulsions in the food industry. © 2023 Society of Chemical Industry.


Asunto(s)
Aminoácidos , Citrus , Emulsiones/química , Citrus/química , Pectinas/química , Concentración de Iones de Hidrógeno
3.
J Mater Chem B ; 11(28): 6478-6490, 2023 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-37326239

RESUMEN

High temperature generated by photothermal therapy (PTT) can trigger an inflammatory response at the tumor site, which not only limits the efficacy of PTT but also increases the risk of tumor metastasis and recurrence. In light of the current limitations posed by inflammation in PTT, several studies have revealed that inhibiting PTT-induced inflammation can significantly improve the efficacy of cancer treatment. In this review, we summarize the research progress made in combining anti-inflammatory strategies to enhance the effectiveness of PTT. The goal is to offer valuable insights for developing better-designed photothermal agents in clinical cancer therapy.


Asunto(s)
Hipertermia Inducida , Neoplasias , Humanos , Terapia Fototérmica , Fototerapia , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Inflamación/tratamiento farmacológico , Antiinflamatorios
4.
Sci Data ; 10(1): 30, 2023 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-36641528

RESUMEN

A consistent dataset of lake surface water temperature, ice cover, water-leaving reflectance, water level and extent is presented. The collection constitutes the Lakes Essential Climate Variable (ECV) for inland waters. The data span combined satellite observations from 1992 to 2020 inclusive and quantifies over 2000 relatively large lakes, which represent a small fraction of the number of lakes worldwide but a significant fraction of global freshwater surface. Visible and near-infrared optical imagery, thermal imagery and microwave radar data from satellites have been exploited. All observations are provided in a common grid at 1/120° latitude-longitude resolution, jointly in daily files. The data/algorithms have been validated against in situ measurements where possible. Consistency analysis between the variables has guided the development of the joint dataset. It is the most complete collection of consistent satellite observations of the Lakes ECV currently available. Lakes are of significant interest to scientific disciplines such as hydrology, limnology, climatology, biogeochemistry and geodesy. They are a vital resource for freshwater supply, and key sentinels for global environmental change.

5.
Chin J Nat Med ; 20(11): 863-872, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36427920

RESUMEN

Peptide dual agonists toward both glucagon-like peptide 1 receptor (GLP-1R) and glucagon receptor (GCGR) are emerging as novel therapeutics for the treatment of type 2 diabetes mellitus (T2DM) patients with obesity. Our previous work identified a Xenopus GLP-1-based dual GLP-1R/GCGR agonist termed xGLP/GCG-13, which showed decent hypoglycemic and body weight lowering activity. However, the clinical utility of xGLP/GCG-13 is limited due to its short in vivo half-life. Inspired by the fact that O-GlcNAcylation of intracellular proteins leads to increased stability of secreted proteins, we rationally designed a panel of O-GlcNAcylated xGLP/GCG-13 analogs as potential long-acting GLP-1R/ GCGR dual agonists. One of the synthesized glycopeptides 1f was found to be equipotent to xGLP/GCG-13 in cell-based receptor activation assays. As expected, O-GlcNAcylation effectively improved the stability of xGLP/GCG-13 in vivo. Importantly, chronic administration of 1f potently induced body weight loss and hypoglycemic effects, improved glucose tolerance, and normalized lipid metabolism and adiposity in both db/db and diet induced obesity (DIO) mice models. These results supported the hypothesis that glycosylation is a useful strategy for improving the in vivo stability of GLP-1-based peptides and promoted the development of dual GLP-1R/GCGR agonists as antidiabetic/antiobesity drugs.


Asunto(s)
Diabetes Mellitus Tipo 2 , Péptido 1 Similar al Glucagón , Ratones , Animales , Péptido 1 Similar al Glucagón/agonistas , Péptido 1 Similar al Glucagón/metabolismo , Receptores de Glucagón/agonistas , Receptores de Glucagón/uso terapéutico , Xenopus laevis/metabolismo , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Glicopéptidos/uso terapéutico , Obesidad/tratamiento farmacológico , Hipoglucemiantes/farmacología , Péptidos/farmacología
6.
Adv Exp Med Biol ; 1370: 153-160, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35882791

RESUMEN

The aim of this study was to investigate the effects of taurine on tissue injury, protein metabolism, and basal metabolism of broilers after chronic heat stress by detecting serum physiological and biochemical indices. In the test, 240 AA + broilers at 7 days of age were randomly divided into five groups: the normal temperature control group (24 ± 2 °C) in group C, the heat stress control group (34 ± 2 °C) in HS group, and the LTau, MTau, and HTau groups in heat under stress conditions, 0.5, 2, and 8 g/L taurine were added to the drinking water, and each group was repeated three times. After 2 weeks of feeding at normal temperature, heat stress began. The test period was 4 weeks. Blood was collected at 6 h, 12 h, 7 d, 14 d, 21 d, and 28 d after heat stress, and serum was separated. The results showed that compared with the HS group, the MTau group had significantly higher total serum protein content (P < 0.05), while the other groups were not significantly different (P > 0.05). The MTau and HTau groups had significantly lower serum uric acid levels than the HS group (P < 0.05). At 7d and 14d, the LTau, MTau, and HTau groups all showed significantly increased T3 and T4 concentrations (P < 0.05). There was no significant difference between the groups thereafter (P > 0.05). Compared with HS group, the MTau group contained significantly reduced serum CK activity, LDH activity, AST activity, and ALT activity (P < 0.05). In conclusion, the effects of taurine on tissue damage, protein metabolism, and basal metabolism of broilers after chronic heat stress were studied by measuring serum physiological and biochemical indices. To provide a theoretical basis for the application of taurine in acute heat-stressed broilers.


Asunto(s)
Pollos , Taurina , Animales , Pollos/fisiología , Dieta , Suplementos Dietéticos , Respuesta al Choque Térmico , Calor , Taurina/farmacología , Ácido Úrico
7.
Adv Exp Med Biol ; 1370: 161-169, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35882792

RESUMEN

The purpose of this study was to investigate the effects of taurine on blood indices of broilers with chronic heat stress and to provide theoretical basis for the application of taurine in the anti-chronic heat stress of broilers. In the test, 240 AA + broilers at 7 days of age were randomly divided into five groups: the normal temperature control group (24 ± 2 °C) in group C, the heat stress control group (34 ± 2 °C) in HS group, and the LTau, MTau, and HTau groups in heat under stress conditions, 0.5 g/L, 2 g/L, and 8 g/L taurine, were added to the drinking water, and each group was repeated three times. After 2 weeks of feeding at normal temperature, heat stress began. The test period was 4 weeks. Blood was collected at 6 h, 12 h, 7 d, 14 d, 21 d, and 28 d after heat stress, and serum was separated. The results showed that compared with the HS group, MTau significantly increased the total serum protein content (P < 0.05), but the other groups were not significantly different (P > 0.05). The MTau and HTau groups contained significantly lowered serum uric acid levels than the HS group (P < 0.05). At 7d and 14d, the LTau, MTau, and HTau groups all exhibited significantly increased T3 and T4 concentrations (P < 0.05). There was no significant difference between the groups at other times (P > 0.05). Compared with the HS group, the MTau group contained significantly reduced serum CK activity, LDH activity, AST activity, and ALT activity (P < 0.05). Compared with the LTau, MTau, and HTau groups, serum MDA content was significantly increased in the heat-stressed broilers (P < 0.05). MTau group contained significantly increased T-AOC, SOD, CAT, and GSH-PX levels (P < 0.05). The other groups were not significantly different (P > 0.05). Compared with group C, serum HSP60 and HSP70 levels were significantly elevated in the HS group (P < 0.05). Compared with the HS group, the LTau and MTau groups contained significantly increased serum HSP60 and HSP70 concentrations (P < 0.05), but the other groups were not significantly different (P > 0.05). In conclusion, taurine can alleviate the symptoms of chronic heat stress of broilers, regulate the metabolism of the body, and improve the antioxidant activity of the body.


Asunto(s)
Antioxidantes , Taurina , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Pollos/fisiología , Suplementos Dietéticos , Proteínas HSP70 de Choque Térmico , Respuesta al Choque Térmico , Calor , Taurina/farmacología , Ácido Úrico
8.
Future Oncol ; 18(21): 2695-2707, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35695676

RESUMEN

Aim: To investigate the efficacy and safety of adjuvant EGFR tyrosine kinase inhibitors for resected EGFR-mutated non-small-cell lung cancer. Materials & methods: Eligible phase II/III randomized controlled trials were included for the network meta-analyses (PROSPERO CRD42021275150). Results: Nine records and 831 patients were involved. Adjuvant chemotherapy followed with osimertinib significantly prolonged disease-free survival compared with chemotherapy (hazard ratio [HR]: 0.2; 95% CI: 0.14-0.29), chemotherapy followed with erlotinib (HR: 0.33; 95% CI: 0.18-0.6), chemotherapy followed with gefitinib (HR: 0.36; 95% CI: 0.16-0.82), gefitinib (HR: 0.26; 95% CI: 0.17-0.41) and icotinib (HR: 0.56; 95% CI: 0.3-0.98). Icotinib was the least likely to cause grade ≥3 adverse events. Conclusion: Chemotherapy followed with osimertinib brings about the best disease-free survival. Icotinib monotherapy shows the best safety.


Patients with early-stage non-small-cell lung cancer have about a one in five chance of cancer recurrence, even after complete resection. Using agents targeting EGFR, known as adjuvant EGFR tyrosine kinase inhibitors, after surgery is an effective way for patients with EGFR-mutated non-small-cell lung cancer to prevent recurrence. However, the optimal agent with favorable efficacy and safety is yet to be determined. This study showed that adjuvant chemotherapy followed with osimertinib had the best efficacy, while adjuvant icotinib monotherapy had the best safety.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Receptores ErbB/genética , Gefitinib/uso terapéutico , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Mutación , Metaanálisis en Red , Inhibidores de Proteínas Quinasas/efectos adversos
9.
J Colloid Interface Sci ; 615: 38-49, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35124505

RESUMEN

Multimodal therapy has attracted increasing interests in tumor treatment due to its high anti-cancer efficacy, and the key is to develop multifunctional nanoagents. The classic multifunctional nanoagents are made up of expensive and complex components, leading to limited practical applications. To solve these problems, we have developed the polyethylene glycol (PEG) coated hollow Cu9S8 nanoparticles (H-Cu9S8/PEG NPs), whose H-Cu9S8 component exhibits the photothermal effect for near-infrared (NIR) photothermal therapy (PTT), the Fenton-like catalytic activity for chemodynamic therapy (CDT), and the drug-loading capacity for chemotherapy. The H-Cu9S8/PEG NPs with a diameter of âˆ¼ 100 nm have been synthesized by sulfurizing cuprous oxide (Cu2O) nanoparticles through "Kirkendall effect", and they exhibit high photothermal conversion efficiency of 40.9%. Meanwhile, the H-Cu9S8/PEG NPs are capable of a Fenton-like reaction, which can be augmented by 2 times under the NIR irradiation. The hollow structure gives the H-Cu9S8/PEG high doxorubicin (DOX) loading capacity (21.1%), and then the DOX release can be further improved by pH and photothermal effect. When the DOX@H-Cu9S8/PEG dispersions are injected into the tumor-bearing mice, the tumor growth can be efficiently inhibited due to the synergistic effect of photothermally-augmented CDT-chemo therapy. Therefore, the DOX@H-Cu9S8/PEG can serve as a multifunctional nanoplatform for photothermally-augmented CDT-chemo treatment of malignant tumors.


Asunto(s)
Nanopartículas , Fototerapia , Animales , Doxorrubicina , Ratones , Nanopartículas/química , Piperidinas , Polietilenglicoles/química
10.
Chem Commun (Camb) ; 57(54): 6584-6595, 2021 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-34137400

RESUMEN

Taking advantage of activatable and imaging-guided properties, stimuli-activated molecular photothermal agents (MPTAs) have drawn great attention in photothermal therapy (PTT) over the past decades. In this review, the recent progress in the study of stimuli-activated MPTAs is summarized from different stimuli, including pH, bioactive small molecules, and enzymes. The features and challenges of stimuli-activated MPTAs are also discussed. This review aims to motivate readers to design and synthesise more efficient MPTAs.


Asunto(s)
Hipertermia Inducida/métodos , Neoplasias/terapia , Fototerapia/métodos , Animales , Humanos , Neoplasias/patología
13.
J Pharmacol Sci ; 139(3): 143-150, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30713113

RESUMEN

The aim of the present study was to examine the neuroprotective effect of Qingnao dripping pills (QNDP), especially the infiltration of neutrophils and macrophages, as well as the mitogen-activated protein kinase (MAPK) signal pathway. Adult male Sprague-Dawley rats were randomized to three groups: sham, MCAO, and QNDP. After 24 h of ischemia and reperfusion, neurological deficit scores and infarct volume were measured. Macrophages and neutrophil infiltration in the ischemic brain were respectively determined with CD68 and MPO immunofluorescence and western blot. The proteins involved in MAPK signaling (SAPK/JNK, P-SAPK/JNK, p38, P-p38, ERK1/2, and P-ERK1/2) were measured by western blotting. In vitro ischemic paradigm (oxygen-glucose deprivation) was performed in SH-SY5Y cells to evaluate the effects of QNDP. The viability and death ration of cells induced OGD/R was measured by MTT and LDH assay. The proteins involved in MAPK signaling were measured by western blotting. The results showed that QNDP treatment significantly improved the neurological deficit scores and reduced infarct size. In addition, QNDP treatment inhibited the number of CD68- and MPO-positive cells in the ischemic brain. It inhibited the MAPK signaling pathway in the ischemic brain and SH- SY5Y cells induced OGD/R.


Asunto(s)
Isquemia Encefálica/tratamiento farmacológico , Medicamentos Herbarios Chinos/farmacología , Fármacos Neuroprotectores/farmacología , Accidente Cerebrovascular/tratamiento farmacológico , Animales , Western Blotting , Isquemia Encefálica/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Humanos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Infiltración Neutrófila/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Accidente Cerebrovascular/patología
14.
Dis Markers ; 2018: 7936736, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30245755

RESUMEN

BACKGROUND: Kudiezi injection is a traditional Chinese medicine for acute cerebral infarction, but the exact mechanisms are poorly understood. OBJECTIVE: To investigate the mechanisms of Kudiezi injection on the inflammatory response in the treatment of acute cerebral infarction. METHODS: This was a prospective study of patients with acute cerebral infarction within 48 h of onset and treated between July 2012 and July 2016 at three hospitals in China. The patients were randomized to routine treatments (control group) versus routine treatments and Kudiezi injection (Kudiezi group). The National Institutes of Health Stroke Score was assessed on days 1, 3, 5, 7, and 14. The patients were tested for serum levels of pro- and anti-inflammatory cytokines (S100 calcium-binding protein B, neuron-specific enolase, interleukin-6, interleukin-10, interleukin-18, and matrix metaloproteinase-9; by enzyme-linked immunosorbent assay) immediately after admission and on days 3, 5, and 14. RESULTS: Stroke scores were improved in both groups from days 1 to 14. On days 5 and 7, stroke scores in the Kudiezi group were lower than in the control group (P < 0.05). Compared with controls, the Kudiezi group had lower serum S100 calcium-binding protein B on day 14; higher interleukin-6 and interleukin-10 on day 3; lower interleukin-6 and interleukin-18 on day 5; and lower interleukin-18 and matrix metaloproteinase-9 on day 14. CONCLUSION: Kudiezi injection could lead to early reduction of interleukin-6, interleukin-18, matrix metaloproteinase-9, neuron-specific enolase, and S100 calcium-binding protein B levels and increases of interleukin-10 levels in patients with acute ischemic stroke. This trial is registered with ClinicalTrials.gov NCT01636154.


Asunto(s)
Biomarcadores/sangre , Infarto Cerebral/sangre , Infarto Cerebral/tratamiento farmacológico , Medicamentos Herbarios Chinos/farmacología , Inflamación/sangre , Enfermedad Aguda , Anciano , Infarto Cerebral/complicaciones , Femenino , Humanos , Inflamación/etiología , Interleucinas/sangre , Masculino , Metaloproteinasa 9 de la Matriz/sangre , Persona de Mediana Edad , Estudios Prospectivos , Subunidad beta de la Proteína de Unión al Calcio S100/sangre , Resultado del Tratamiento
15.
Environ Sci Pollut Res Int ; 25(2): 1359-1374, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29090433

RESUMEN

Chlorophyll-a (Chla) is an important indicator of water quality and eutrophication status. Monitoring Chla concentration (C Chla ) and understanding the interactions between C Chla and related environmental factors (hydrological and meteorological conditions, nutrients enrichment, etc.) are necessary for assessing and managing water quality and eutrophication. An acceptable Landsat 8 OLI-based empirical algorithm for C Chla has been developed and validated, with a mean absolute percentage error of 14.05% and a root mean square error of 1.10 µg L-1. A time series of remotely estimated C Chla was developed from 2013 to 2015 and examined the relationship of C Chla to inflow rate, rainfall, temperature, and sunshine duration. Spatially, C Chla values in the riverine zone were higher than in the transition and lacustrine zones. Temporally, mean C Chla value were ranked as spring > summer > autumn > winter. A significant positive correlation [Pearson correlation coefficient (r) = 0.88, p < 0.001] was observed between the inflow rate and mean C Chla in the northwest segment of the Xin'anjiang Reservoir. However, no significant relation was observed between mean C Chla and meteorological conditions. Mean (± standard deviation) value for the ratio of total nitrogen concentration to total phosphorus concentration in our in situ dataset is 75.75 ± 55.72. This result supports that phosphorus is the restrictive factor to algal growth in Xin'anjiang Reservoir. In addition, the response of nutrients to Chla has spatial variabilities. Current results show the potential of Landsat 8 OLI data for estimating Chla in slight turbid reservoir and indicate that external pollution loading is an important driving force for the Chla spatiotemporal variability.


Asunto(s)
Algoritmos , Clorofila/análisis , Monitoreo del Ambiente , Calidad del Agua , China , Clorofila A , Monitoreo del Ambiente/métodos , Eutrofización , Agua Dulce/química , Nitrógeno/análisis , Fósforo/análisis
16.
Sci Rep ; 7: 40326, 2017 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-28074871

RESUMEN

We developed and validated an empirical model for estimating chlorophyll a concentrations (Chla) in Lake Taihu to generate a long-term Chla and algal bloom area time series from MODIS-Aqua observations for 2003 to 2013. Then, based on the long-term time series data, we quantified the responses of cyanobacterial dynamics to nutrient enrichment and climatic conditions. Chla showed substantial spatial and temporal variability. In addition, the annual mean cyanobacterial surface bloom area exhibited an increasing trend across the entire lake from 2003 to 2013, with the exception of 2006 and 2007. High air temperature and phosphorus levels in the spring can prompt cyanobacterial growth, and low wind speeds and low atmospheric pressure levels favor cyanobacterial surface bloom formation. The sensitivity of cyanobacterial dynamics to climatic conditions was found to vary by region. Our results indicate that temperature is the most important factor controlling Chla inter-annual variability followed by phosphorus and that air pressure is the most important factor controlling cyanobacterial surface bloom formation followed by wind speeds in Lake Taihu.


Asunto(s)
Cianobacterias/metabolismo , Imagenología Tridimensional , Lagos/microbiología , Conceptos Meteorológicos , Nitrógeno/análisis , Fósforo/análisis , Análisis Espectral/métodos , Presión Atmosférica , Calibración , Clorofila/metabolismo , Clorofila A , Eutrofización , Modelos Biológicos , Reproducibilidad de los Resultados , Estaciones del Año , Temperatura , Viento
17.
Sci Rep ; 5: 10464, 2015 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-25993914

RESUMEN

Coating of polydimethylsiloxane (PDMS) surface with a traditional Chinese herb extract chlorogenic acid (CA) solves the contemporary problem of sterilization of PDMS surface. The E. coli grows slower and has a higher death rate on the CA-coated PDMS surfaces. A smoother morphology of these E. coli cell wall is observed by atomic force microscopy (AFM). Unlike the reported mechanism, where CA inhibits bacterial growth by damaging the cell membrane in the bulk solution, we find the CA-coated PDMS surface also decreases the stiffness of the cell wall. A decrease in the Young's modulus of the cell wall from 3 to 0.8 MPa is reported. Unexpectedly, the CA effect on the swarming ability and the biofilm stability of the bacteria can be still observed, even after they have been removed from the CA environment, indicating a decrease in their resistance to antibiotics for a prolonged time. The CA-coated PDMS surface shows better antibiotic effect against three types of both Gram-positive and Gran-negative bacteria than the gentamicin-coated PDMS surface. Coating of CA on PDMS surface not only solves the problem of sterilization of PDMS surface, but also shines light on the application of Chinese traditional herbs in scientific research.


Asunto(s)
Antibacterianos/química , Ácido Clorogénico/química , Dimetilpolisiloxanos/química , Antibacterianos/farmacología , Bacillus subtilis/efectos de los fármacos , Bacillus subtilis/fisiología , Biopelículas/efectos de los fármacos , Pared Celular/química , Ácido Clorogénico/farmacología , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Módulo de Elasticidad , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Escherichia coli/fisiología , Microscopía de Fuerza Atómica , Pseudomonas aeruginosa/efectos de los fármacos , Pseudomonas aeruginosa/fisiología , Propiedades de Superficie
18.
Environ Sci Pollut Res Int ; 21(24): 14078-90, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25053284

RESUMEN

The development of techniques for real-time monitoring of water quality is of great importance for effectively managing inland water resources. In this study, we first analyzed the absorption and fluorescence properties in a large subtropical reservoir and then used a chromophoric dissolved organic matter (CDOM) fluorescence monitoring sensor to predict several water quality parameters including the total nitrogen (TN), total phosphorus (TP), chemical oxygen demand (COD), dissolved organic carbon (DOC), and CDOM fluorescence parallel factor analysis (PARAFAC) components in the reservoir. The CDOM absorption coefficient at 254 nm (a(254)), the humic-like component (C1), and the tryptophan-like component (C3) decreased significantly along a gradient from the northwest to the lake center, northeast, southwest, and southeast region in the reservoir. However, no significant spatial difference was found for the tyrosine-like component (C2), which contributed only four marked peaks. A highly significant linear correlation was found between the a(254) and CDOM concentration measured using the CDOM fluorescence sensor (r(2) = 0.865, n = 76, p < 0.001), indicating that CDOM concentrations could act as a proxy for the CDOM absorption coefficient measured in the laboratory. Significant correlations were also found between the CDOM concentration and TN, TP, COD, DOC, and the maximum fluorescence intensity of C1, suggesting that the real-time monitoring of CDOM concentrations could be used to predict these water quality parameters and trace the humic-like fluorescence substance in clear aquatic ecosystems with DOC <2 mg/L and total suspended matter (TSM) concentrations <15 mg/L. These results demonstrate that the CDOM fluorescence sensor is a useful tool for on-line water quality monitoring if the empirical relationship between the CDOM concentration measured using the CDOM fluorescence sensor and the water quality parameters is calibrated and validated.


Asunto(s)
Monitoreo del Ambiente/métodos , Fluorescencia , Calidad del Agua/normas , Abastecimiento de Agua/análisis , Análisis de la Demanda Biológica de Oxígeno , Clima , Nitrógeno , Fósforo , Espectrometría de Fluorescencia/métodos
19.
PLoS One ; 8(10): e77515, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24204852

RESUMEN

CDOM biogeochemical cycle is driven by several physical and biological processes such as river input, biogeneration and photobleaching that act as primary sinks and sources of CDOM. Watershed-derived allochthonous (WDA) and phytoplankton-derived autochthonous (PDA) CDOM were exposed to 9 days of natural solar radiation to assess the photobleaching response of different CDOM sources, using absorption and fluorescence (excitation-emission matrix) spectroscopy. Our results showed a marked decrease in total dissolved nitrogen (TDN) concentration under natural sunlight exposure for both WDA and PDA CDOM, indicating photoproduction of ammonium from TDN. In contrast, photobleaching caused a marked increase in total dissolved phosphorus (TDP) concentration for both WDA and PDA CDOM. Thus TDN:TDP ratios decreased significantly both for WDA and PDA CDOM, which partially explained the seasonal dynamic of TDN:TDP ratio in Lake Taihu. Photobleaching rate of CDOM absorption a(254), was 0.032 m/MJ for WDA CDOM and 0.051 m/MJ for PDA CDOM from days 0-9, indicating that phototransformations were initially more rapid for the newly produced CDOM from phytoplankton than for the river CDOM. Extrapolation of these values to the field indicated that 3.9%-5.1% CDOM at the water surface was photobleached and mineralized every day in summer in Lake Taihu. Photobleaching caused the increase of spectral slope, spectral slope ratio and molecular size, indicating the CDOM mean molecular weight decrease which was favorable to further microbial degradation of mineralization. Three fluorescent components were validated in parallel factor analysis models calculated separately for WDA and PDA CDOM. Our study suggests that the humic-like fluorescence materials could be rapidly and easily photobleached for WDA and PDA CDOM, but the protein-like fluorescence materials was not photobleached and even increased from the transformation of the humic-like fluorescence substance to the protein-like fluorescence substance. Photobleaching was an important driver of CDOM and nutrients biogeochemistry in lake water.


Asunto(s)
Fotoblanqueo , Fitoplancton/fisiología , Absorción , Compuestos de Amonio/metabolismo , Fluorescencia , Agua Dulce/microbiología , Nitrógeno/metabolismo , Fósforo/metabolismo , Ríos/microbiología , Estaciones del Año , Energía Solar , Espectrometría de Fluorescencia/métodos , Luz Solar
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