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Zinc (Zn) is an essential trace element in the human body, and its deficiency can seriously affect health. Agronomic Zn biofortification with ZnO nanoparticles (ZnO NPs) in consumable wheat prospectively relieves Zn deficiency. We developed an elemental quantitative imaging laser ablation-inductively coupled plasma optical emission spectrometry method to examine the distributions of Zn and other micronutrient elements in wheat grain and the endosperm. After foliar application of ZnO NPs (four rounds), Zn content in the endosperm can be significantly increased (221 ± 61%), and the Zn, Ca, Mg, and P content gradient decreased from the outside seed coat and aleurone layer to the endosperm, whereas the Fe, Mn, K, Cu, Sr, and Ba content gradient decreased from the crease region to the deeper endosperm. This may indicate how different elements enter the endosperm. Foliar application of ZnO NPs did not change the micronutrient accumulation pattern but did change their contents in wheat grain.
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Terapia a Laser , Oligoelementos , Óxido de Zinco , Humanos , Óxido de Zinco/química , Endosperma/química , Triticum , Zinco/análise , Oligoelementos/análise , Grão Comestível/química , Análise EspectralRESUMO
Purpose: This study evaluated the effect of a combined infusion of dexmedetomidine and esketamine on the quality of recovery in patients undergoing modified radical mastectomy. Methods: A total of 135 patients were randomly divided into three groups: dexmedetomidine group (group D) received dexmedetomidine (0.5 µg/kg loading, 0.4 µg/kg/h infusion), dexmedetomidine plus low-dose esketamine group (group DE1) received dexmedetomidine (0.5 µg/kg loading, 0.4 µg/kg/h infusion) and esketamine (0.5 mg/kg loading, 2 µg/kg/min infusion), dexmedetomidine plus high-dose esketamine group (group DE2) received dexmedetomidine (0.5 µg/kg loading, 0.4 µg/kg/h infusion) and esketamine (0.5 mg/kg loading, 4 µg/kg/min infusion). The primary outcome was the overall quality of recovery-15 (QoR-15) scores at 1 day after surgery. The secondary endpoints were total QoR-15 scores at 3 days after surgery, propofol and remifentanil requirement, awaking and extubation time, postoperative visual analogue scale (VAS) pain scores, rescue analgesic, nausea and vomiting, bradycardia, excessive sedation, nightmares, and agitation. Results: The overall QoR-15 scores were much higher in groups DE1 and DE2 than in groups D 1 and D 3 days after surgery (P < 0.05). VAS pain scores at 6, 12, 24 h postoperatively, propofol and remifentanil requirements were significantly lower in groups DE1 and DE2 than in group D (P < 0.05). Compared with group D, awaking time, extubation time, and post-anesthesia care unit (PACU) stay were significantly prolonged in groups DE1 and DE2 (P < 0.05) and were much longer in group DE2 than in group DE1 (P < 0.05). The proportion of postoperative rescue analgesics and bradycardia was higher and the incidence of excessive sedation was lower in group D than in groups DE1 and DE2 (P < 0.05). Conclusion: Dexmedetomidine plus esketamine partly improved postoperative recovery quality and decreased the incidence of bradycardia but prolonged awaking time, extubation time, and PACU stay, especially dexmedetomidine plus 4 µg/kg/min esketamine.
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Neoplasias da Mama , Dexmedetomidina , Propofol , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Mastectomia Radical Modificada , Dexmedetomidina/uso terapêutico , Bradicardia , Remifentanil , Mastectomia , DorRESUMO
INTRODUCTION: Surgical management is commonly used for thyroid cancer. We evaluated the effects of systemic lidocaine versus dexmedetomidine on the recovery quality and analgesia after thyroid cancer surgery. METHODS: A total of 120 patients with thyroid cancer were randomly allocated to group L (received lidocaine 1.5 mg/kg loading, continuously infused 1.5 mg/kg per hour), group D (received dexmedetomidine 0.5 µg/kg loading, continuously infused 0.5 µg/kg per hour) and group C (received normal saline), with 40 cases in each group. Anaesthesia induction and maintenance were performed using target-controlled infusions (TCIs) of propofol and remifentanil. The primary outcome of the quality of recovery-15 (QoR-15) score was recorded on the day before surgery and postoperative day 1 (POD1). Secondary outcomes included the consumption of remifentanil during surgery, time to first required rescue analgesia, number of patients requiring rescue analgesia, postoperative cumulative consumption of tramadol, visual analogue scale (VAS) pain score, incidence of postoperative nausea or vomiting (PONV) and side effects. RESULTS: The total score of the QoR-15 at POD1 (median, IQR) was higher in group L (128.0, 122.0-132.8) and group D (127.5, 122.5-132.5) compared to group C (118.5, 113.0-123.5) (P = 0.000). Compared to group C, systemic lidocaine and dexmedetomidine reduced cumulative consumption of remifentanil and VAS pain score (P = 0.000). The time to first required rescue analgesia (mean, SD) was longer in group L (8.1 h, 1.2 h) and group D (8.5 h, 1.9 h) than group C (5.9 h, 0.9 h) (P = 0.000). The number of patients requiring rescue analgesia was lower in group L (8/40, 20%) and group D (6/40, 15%) than group C (16/40, 40%) (P = 0.029), and cumulative consumption of tramadol (mean, SD) was lower in group L (44.0 mg, 17.1 mg) and group D (51.7 mg, 14.1 mg) than group C (73.9 mg, 18.4 mg) (P = 0.000). The incidence of PONV in group L (7/40, 17.5%) and group D (9/40, 22.5%) was lower than group C (18/40, 45.0%) (P = 0.016). Bradycardia (heart rate less than 50 beats/min or lower) was noted in 25 patients (25/40, 62.5%), which was reversed by intravenous administration of atropine 0.5 mg. CONCLUSION: Systemic lidocaine and dexmedetomidine had similar effects on enhancing the quality of recovery, alleviating the intensity of pain and reducing the incidence of PONV after thyroid cancer surgery. However, dexmedetomidine may result in bradycardia. Therefore, lidocaine was superior to dexmedetomidine. TRIAL REGISTRATION: ChiCTR.org.cn (ChiCTR2000038442). Registered on September 22, 2020.
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Quantification of trace and minor nutrient elements is crucial for maintaining human health. A reliable laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) method for food materials was developed by combining fine food powder (dm < 3 µm) pellets as the external standard with an average C content as the internal standard (IS). The finer and homogeneous aerosol produced by ablating the fine powder pellets is beneficial for transportation and analyte ionization in ICP, which helps alleviate the matrix effects and improves the analytical precision and accuracy. The average C content is 39.9 ± 1.9% for plant-derived foods (n = 22) and 46.9 ± 1.1% for animal-derived foods (n = 7). The accuracy (recovery, 80-120%) and precision (RSD, 0.5-9.8%) were validated by analyzing a series of food certified reference materials. The high-throughput method is a promising alternative for routine sample analysis in food safety laboratories.
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Terapia a Laser , Lasers , Animais , Espectrometria de Massas/métodos , Pós , Análise EspectralRESUMO
Using boron as a test analyte, laser ablation (LA) solution sampling multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) is proposed and validated as a fast method for isotopic analysis in natural liquids and digested samples without any prior purification process. We demonstrated that the solution reference standard can be used as a bracketing standard for in situ δ11B analysis in solids. Based on a sensitivity enhancement of 8- to 9-fold, all testing solutions were diluted in a 5% (v/v) NH3·H2O instead of classical 2% (v/v) HNO3. With a discrete and minimal sample solvent loading by the LA sampling strategy, it produces nearly "dry" plasma conditions that tolerate the sample matrix remarkably. The memory effect, one of the most difficult challenges in boron analysis, was dramatically eliminated with only 15 s wash time; thus, each analysis took less than 100 s. No significant matrix effects were observed for varying 50-100% boron concentrations in the samples and varying 20-60% NH3·H2O matrix used for the dilution, as well as for samples doped with a 1/100 synthetic seawater matrix. The external precision of δ11B measurements in NIST 951a was ± 0.30 (2SD). Good agreement with the values described in literature studies was achieved for δ11B measurements in eight geological reference materials, with precisions between 0.4 and 0.7 (2SD), confirming the accuracy of the proposed method. The proposed method offers advantages of simple sample preparation, fast analysis, and little use of chemical reagents.
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Boro , Terapia a Laser , Boro/química , Espectrometria de Massas/métodos , Água do Mar , Manejo de EspécimesRESUMO
BACKGROUND: Parathyroidectomy has been proposed as a method for reducing parathyroid hormone levels. We evaluated the effects of ultrasound-guided bilateral superficial cervical plexus block (BSCPB) on the quality of recovery of uremia patients with secondary hyperparathyroidism (SHPT) following parathyroidectomy. METHODS: Eighty-two uremia patients who underwent parathyroidectomy and exhibited SHPT were randomly allocated to the BSCPB group or the control group (CON group). The patients received ultrasound-guided BSCPB with 7.5 ml of ropivacaine 0.5% on each side (BSCPB group) or equal amount of 0.9% normal saline (CON group). The primary outcome of the Quality of Recovery-40(QoR-40) score was recorded on the day before surgery and postoperative day 1(POD1). Secondary outcomes including total consumption of remifentanil, time to first required rescue analgesia, number of patients requiring rescue analgesia, and total consumption of tramadol during the first 24 h after surgery were recorded. The occurrence of postoperative nausea or vomiting (PONV) and the visual analogue scale (VAS) scores were assessed and recorded. RESULTS: The scores on the pain and emotional state dimensions of the QoR-40 and the total QoR-40 score were higher in the BSCPB group than in the CON group on POD1 (P = 0.000). Compared with the CON group, the total consumption of remifentanil was significantly decreased in the BSCPB group (P = 0.000). The BSCPB group exhibited longer time to first required rescue analgesia (P = 0.018), fewer patients requiring rescue analgesia (P = 0.000), and lower postoperative total consumption of tramadol during the first 24 h after surgery (P = 0.000) than the CON group. The incidence of PONV was significantly lower in the BSCPB group than in the CON group (P = 0.013). The VAS scores in the BSCPB group were lower than those in the CON group at all time-points after surgery (P = 0.000). CONCLUSION: Ultrasound-guided BSCPB with ropivacaine 0.5% can enhance the quality of recovery, postoperative analgesia, and reduce the incidence of PONV in uremia patients with SHPT following parathyroidectomy. TRIAL REGISTRATION: ChiCTR1900027185 . (Prospective registered). Initial registration date was 04/11/2019.
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Bloqueio do Plexo Cervical/métodos , Hiperparatireoidismo Secundário/epidemiologia , Dor Pós-Operatória/epidemiologia , Paratireoidectomia/métodos , Náusea e Vômito Pós-Operatórios/epidemiologia , Ultrassonografia de Intervenção/métodos , Uremia/epidemiologia , China/epidemiologia , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
BACKGROUND: A few studies have reported that administration of lidocaine and dexmedetomidine relieves the incidence of postoperative nausea and vomiting (PONV). We explored whether combined infusion of lidocaine plus dexmedetomidine had lower occurrence of PONV undergoing laparoscopic hysterectomy with general anesthesia. METHODS: A total of 248 women undergoing elective laparoscopic hysterectomy were allocated into the following four groups: the control group (group C, n = 62) received an equal volume of saline, the lidocaine group (group L, n = 62) received intravenous lidocaine (bolus infusion of 1.5 mg/kg over 10 min, 1.5 mg/kg/h continuous infusion), the dexmedetomidine group (group D, n = 62) received dexmedetomidine administration (bolus infusion of 0.5 µg/kg over 10 min, 0.4 µg/kg/h continuous infusion), and the lidocaine plus dexmedetomidine group (group LD, n = 62) received combination of lidocaine (bolus infusion of 1.5 mg/kg over 10 min, 1.5 mg/kg/h continuous infusion) and dexmedetomidine administration (bolus infusion of 0.5 µg/kg over 10 min, 0.4 µg/kg/h continuous infusion). The primary outcome was the incidence of nausea, vomiting, and PONV during the first 48 h after surgery. The secondary outcomes included the incidence of total 24 h PONV after surgery, intraoperative remifentanil requirement, postoperative pain visual analogue scale (VAS) scores and fentanyl consumption, the incidence of bradycardia, agitation, shivering, and mouth dry during post-anesthesia care unit (PACU) stay period. RESULTS: The occurrence of nausea and PONV in group LD (5.0 and 8.3%) at 0-2 h after operation was lower than group C (21.7 and 28.3%) (P < 0.05). There was no statistically significant difference with respect to occurrence of nausea and PONV in groups L (13.3 and 20.0%) and D (8.3 and 13.3%) at 0-2 h after operation compared to group C (21.7 and 28.3%). The incidence of nausea, vomiting, and PONV at 2-24 and 24-48 h after surgery in all four groups was not statistically significant. The incidence of total 24 h PONV in group LD (33.3%) was significantly decreased compared to group C (60.0%) (P < 0.05). The cumulative consumption of fentanyl at 6 and 12 h after surgery was significantly reduced in group LD compared to other three groups (P < 0.05). The pain VAS scores were significantly decreased at 2, 6, and 12 h after operation in group LD compared to other three groups (P < 0.05). Remifentanil dose in the intraoperative period was significantly lower in groups LD and D compared with groups C and L (P < 0.05). The number of mouth dry, bradycardia, and over sedation during the PACU stay period was markedly increased in group LD (28.3, 30.0, and 35.0%, respectively) compared with groups C (1.7, 1.7, and 3.3%, respectively) and L (3.3, 5.0, and 6.7%, respectively) (P < 0.05). CONCLUSIONS: Lidocaine combined with dexmedetomidine infusion markedly decreased the occurrence of nausea and PONV at 0-2 h as well as the total 24 h PONV. However, it significantly increased the incidence of mouth dry, bradycardia, and over sedation during the PACU stay period after laparoscopic hysterectomy with general anesthesia. TRIAL REGISTRATION: ClinicalTrials.gov ( NCT03809923 ), registered on January 18, 2019.
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Dexmedetomidina/administração & dosagem , Histerectomia/métodos , Lidocaína/administração & dosagem , Náusea e Vômito Pós-Operatórios/epidemiologia , Adulto , Anestesia Geral/métodos , Bradicardia/epidemiologia , Dexmedetomidina/efeitos adversos , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Fentanila/administração & dosagem , Humanos , Incidência , Laparoscopia/métodos , Lidocaína/efeitos adversos , Pessoa de Meia-Idade , Dor Pós-Operatória/epidemiologia , Remifentanil/administração & dosagemRESUMO
BACKGROUND: Surgical-related inflammatory responses have negative effects on postoperative recovery. Intravenous (IV) lidocaine and dexmedetomidine inhibits the inflammatory response. We investigated whether the co-administration of lidocaine and dexmedetomidine could further alleviate inflammatory responses compared with lidocaine or dexmedetomidine alone during laparoscopic hysterectomy. METHODS: A total of 160 patients were randomly allocated into four groups following laparoscopic hysterectomy: the control group (group C) received normal saline, the lidocaine group (group L) received lidocaine (bolus infusion of 1.5 mg/kg over 10 min, 1.5 mg/kg/h continuous infusion), the dexmedetomidine group (group D) received dexmedetomidine (bolus infusion of 0.5 µg/kg over 10 min, 0.4 µg/kg/h continuous infusion), and the lidocaine plus dexmedetomidine group (group LD) received a combination of lidocaine (bolus infusion of 1.5 mg/kg over 10 min, 1.5 mg/kg/h continuous infusion) and dexmedetomidine (bolus infusion of 0.5 µg/kg over 10 min, 0.4 µg/kg/h continuous infusion). The levels of plasma interleukin-1 (IL-1), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) at different time points were the primary outcomes. Secondary outcomes included hemodynamic variables, postoperative visual analogue scale (VAS) scores, time to first flatus, and incidence of nausea and vomiting after surgery. RESULTS: The levels of plasma IL-1, IL-6, and TNF-α were lower in groups D and LD than in group C and were lowest in group LD at the end of the procedure and 2 h after the operation (P < 0.05). The VAS scores were decreased in groups D and LD compared with group C (P < 0.05). The heart rate (HR) was decreased at the end of the procedure and 2 h after the operation in groups D and LD compared to groups C and L (P < 0.001). The mean blood pressure (MBP) was lower at 2 h after the operation in groups L, D, and LD than in group C (P < 0.001). There was a lower incidence of postoperative nausea and vomiting (PONV) in group LD than in group C (P < 0.05). CONCLUSIONS: The combination of lidocaine and dexmedetomidine significantly alleviated the inflammatory responses, decreased postoperative pain, and led to fewer PONV in patients undergoing laparoscopic hysterectomy. TRIAL REGISTRATION: ClinicalTrials.gov ( NCT03276533 ), registered on August 23, 2017.
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Dexmedetomidina/farmacologia , Histerectomia , Inflamação/prevenção & controle , Interleucina-1/sangue , Interleucina-6/sangue , Lidocaína/farmacologia , Fator de Necrose Tumoral alfa/sangue , Analgésicos não Narcóticos/administração & dosagem , Analgésicos não Narcóticos/sangue , Analgésicos não Narcóticos/farmacologia , Anestésicos Locais/administração & dosagem , Anestésicos Locais/sangue , Anestésicos Locais/farmacologia , Dexmedetomidina/administração & dosagem , Dexmedetomidina/sangue , Quimioterapia Combinada , Feminino , Humanos , Inflamação/sangue , Infusões Intravenosas , Laparoscopia , Lidocaína/administração & dosagem , Lidocaína/sangue , Pessoa de Meia-Idade , Dor Pós-Operatória/sangue , Dor Pós-Operatória/prevenção & controle , Náusea e Vômito Pós-Operatórios/sangue , Náusea e Vômito Pós-Operatórios/prevenção & controle , Estudos Prospectivos , Fator de Necrose Tumoral alfa/efeitos dos fármacosRESUMO
The mobility and fate of Cd in soil are mainly controlled by active substances such as iron minerals and organic matter. Iron minerals and organic matter often coexist in the form of iron-organic associations (IOA), which have large specific surface areas and many functional groups, potentially affecting Cd adsorption. However, little is known about Cd adsorption by IOA. This study investigated Cd adsorption by the synthetic IOA under different conditions. The results indicate Cd adsorption increased with the increasing amount of IOA, while the adsorption efficiency decreased gradually. pH significantly affects Cd adsorption, because the Cd speciation and the surface charge of IOA changed under different pH conditions. Under alkaline condition, part of Cd would form hydroxide precipitate, facilitating Cd adsorption by IOA. The composition of organic matter in IOA didn't significantly affect Cd adsorption.
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Ferro , Poluentes do Solo , Adsorção , Cádmio , Minerais , SoloRESUMO
Consumption of rice (Oryza sativa) grain is a major pathway by which humans are exposed to Cd, especially in non-smoking Asian populations. Although the stable isotope signatures of Cd offer a potential tool for tracing its sources, little is known about the isotopic fractionation of Cd across the entire soil-rice-human continuum. Cadmium isotope ratios were determined in field soils, rice grain, and human urine collected from two Cd-contaminated regions in southern China. Additionally, Cd isotopic fractionation in rice plants was investigated using two transgenic plants differing in Cd uptake and accumulation. Analysis of isotope ratios revealed a preferential enrichment of the heavy Cd isotopes from soil to rice grain (δ114/110Cdgrain-soil = +0.40) and from grain to urine (δ114/110Cdurine-grain = +0.40) in both regions. The first increase was mainly caused by partitioning between the soil solid phase and the soil solution, with heavier Cd preferentially enriching in the soil solution. Within the rice plant, we identified multiple processes that alter the isotope ratio, but the net effect throughout the plant was comparatively small. Cd fractionation in humans is presumably due to the preferential enrichment of heavier Cd isotopes by metal transporters DMT1 and ZIP8 (responsible for the absorption of Cd into body from the foods). These findings provide important insights into the Cd isotopic fractionation through the soil-rice-human continuum and are helpful for tracing the sources of Cd.
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Oryza , Poluentes do Solo , Cádmio/análise , China , Humanos , Isótopos , Solo , Poluentes do Solo/análiseRESUMO
BACKGROUND: Intravenous lidocaine and dexmedetomidine treatments have been proposed as methods for inhibiting cough. We compared the efficacy of intravenous lidocaine and dexmedetomidine treatments on inhibiting cough during the tracheal extubation period after thyroid surgery. METHODS: One hundred eighty patients undergoing thyroid surgeries were randomly allocated to the LIDO group (received lidocaine 1.5 mg/kg loading, 1.5 mg/kg/h infusion), the DEX group (received dexmedetomidine 0.5 µg/kg loading, 0.4 µg/kg/h infusion) and the CON group (received saline), with 60 cases in each group. The primary outcomes of cough were recorded. Secondary outcomes included hemodynamic variables, awareness time, volume of drainage, the postoperative visual analogue scale and adverse effects were recorded. RESULTS: The incidence of cough were significantly lower in the LIDO group (28.3%) and the DEX group (31.7%) than that in the CON group (66.7%) (P = 0.000). Additionally, both moderate and severe cough were significantly lower in the LIDO group (13.3%) and the DEX group (13.4%) than these in the CON group (43.4%) (P < 0.05). Compared with the two treatment groups, both mean arterial blood pressure and heart rate were significantly increased in the CON group during tracheal extubation (P < 0.05). Compared with the CON group, the volume of drainage was significantly reduced in the two treatment groups within 48 h after surgery (P < 0.05). compared with the CON group, the postoperative visual analogue scale was significantly lower in groups LIDO and DEX after surgery(P < 0.05). Compared with the LIDO group and the CON group, the time to awareness was longer in the DEX group (P < 0.05). In the DEX group, bradycardia was noted in 35 patients, while no bradycardia was noted in LIDO group and CON group. CONCLUSION: Compared with intravenous infusions of normal saline, both lidocaine and dexmedetomidine had equal effectiveness in attenuating cough and hemodynamic changes during the tracheal extubation period after thyroid surgery, and both of these treatments were able to reduce the volume of postoperative bleeding and provide better analgesic effect after surgery. But intravenous infusions of dexmedetomidine resulted in bradycardia and delayed the time to awareness when compared with lidocaine and normal saline. TRIAL REGISTRATION: ChiCTR1800017482 . (Prospective registered). Initial registration date was 01/08/2018.
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Extubação/tendências , Tosse/tratamento farmacológico , Dexmedetomidina/administração & dosagem , Lidocaína/administração & dosagem , Medição da Dor/efeitos dos fármacos , Glândula Tireoide/cirurgia , Adulto , Extubação/efeitos adversos , Período de Recuperação da Anestesia , Anestésicos Locais/administração & dosagem , Tosse/diagnóstico , Tosse/etiologia , Feminino , Humanos , Hipnóticos e Sedativos/administração & dosagem , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Medição da Dor/métodos , Projetos Piloto , Estudos ProspectivosRESUMO
A novel interrupted gas flow (IF) technique has been proposed for highly sensitive determination of ultratrace levels of arsenic and antimony in water samples by atmospheric pressure glow discharge (APGD) excitation source coupled with HCl-KBH4 hydride generation (HG). It is demonstrated that the gas flow interruption technique provides a dramatic and reproducible enhancement of emission signals of 1-2 orders of magnitude for As and Sb over conventional continuous gas flow (CF) in APGD. The enhanced analyte emission sensitivities in IF-APGD were investigated from the viewpoint of changes in plasma excitation temperature and analyte density. With eight As lines as the thermometric probe, no measurable change in excitation temperature was found, suggesting that the enhancement is caused by an increase in analyte number density in the plasma immediately following the gas flow interruption. Furthermore, the enhancement factor was found to increase with the time interval in between the gas interruption, supporting an analyte adsorption (or trap)-release mechanism hypothesis. Under optimized conditions, the detection limits (DLs) of IF-APGD mode for As and Sb were calculated to be 0.02 and 0.003 µg L-1, which are, respectively, about 27- and 120-fold improved compared to CF-APGD mode. The linearity of calibration for both As and Sb reached R2 > 0.999 in the 0.1-5 µg L-1 range. The accuracy of the proposed method was validated by the determination of certified reference materials (CRMs), and the results agreed well with the certified values.
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In this study, a novel high efficiency vapor generation strategy was proposed on the basis of solution anode glow discharge for the determination of Cd and Zn by atomic fluorescence spectrometry. In this approach, a glow discharge microplasma was acted as a gaseous cathode to initiate the plasma electrochemical vapor generation of Cd and Zn. Cadmium/zinc ions could be converted into molecular species efficiently at the plasma-liquid interface from a supporting electrolyte (HCl, pH = 3.2). It was found that the overall efficiency of the plasma electrochemical vapor generation (PEVG) system was much higher than the conventional electrochemical hydride generation (EcHG) and HCl-KBH4 system. With no requirement for other reducing reagents, this new approach enabled us to detect Cd and Zn with detection limits as low as 0.003 µg L-1 for Cd and 0.3 µg L-1 for Zn. Good repeatability (relative standard deviation (RSD), n = 5) was 2.4% for Cd (0.1 µg L-1) and 1.7% for Zn (10 µg L-1) standard. The accuracy of the proposed method was successfully validated through analysis of cadmium in reference material of stream sediment (GBW07311), soil (GBW07401), rice (GBW10045), and zinc in a simulated water sample (GSB 07-1184-2000). Replacing a metal electrode with a plasma offers the advantage of eliminating potential interactions between the species in liquid and the electrode, which solves the issues associated with electrode encountered in conventional EcHG. The ability to initiate electrochemical vapor generation reactions at the plasma-liquid interface opens a new approach for chemical vapor generation based on interactions between plasma gas-phase electrons and solutions.
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BACKGROUND: Intravenous (IV) lidocaine and dexmedetomidine have been shown to decrease postoperative pain, reduce analgesic consumption and facilitate return of bowel function. We investigated whether lidocaine combined with dexmedetomidine infusion was superior in controlling pain and recovery of bowel function. METHODS: A total of 240 women undergoing elective abdominal hysterectomy were randomly assigned into four groups: group CON received normal saline infusion, group LIDO received lidocaine infusion (1.5 mg/kg loading, 1.5 mg/kg/h infusion), group DEX received dexmedetomidine infusion (0.5 µg/kg loading, 0.4 µg/kg/h infusion) and group LIDO+DEX received lidocaine (1.5 mg/kg loading, 1.5 mg/kg/h infusion) and dexmedetomidine infusions (0.5 µg/kg loading, 0.4 µg/kg/h infusion). The primary outcome was visual analog pain scale (VAS) scores at 1, 4, 8, 12, 24, and 48 hours after surgery. The secondary outcomes included time to first bowel sounds and flatus, postoperative fentanyl requirement and perioperative propofol and remifentanil consumption. RESULTS: The VAS scores were significantly lower in groups LIDO and DEX at 4, 8, and 12 hours compared to group CON after surgery (P<0.01). The VAS scores were also significantly lower in group LIDO+DEX at 1, 4, 8, 12, and 24 hours compared to other three groups after surgery (P<0.01). Time to first bowel sounds and flatus was significantly shorter in groups LIDO and LIDO+DEX than groups CON and DEX (P<0.01). Postoperative fentanyl requirement was significantly lower in group LIDO at 1 and 4 hours and in group DEX at 1, 4, 8 hours compared to group CON after surgery (P<0.01). Postoperative fentanyl requirement was also significantly lower in group LIDO+DEX at 1, 4, 8, 12, 24 and 48 hours compared to other three groups after surgery (P<0.01). Propofol and remifentanil consumption was significantly lower in groups LIDO, DEX and LIDO+DEX compared to group CON (P<0.01). CONCLUSIONS: Lidocaine combined with dexmedetomidine infusion significantly improved postoperative pain and enhanced recovery of bowel function undergoing abdominal hysterectomy.
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Analgésicos não Narcóticos/administração & dosagem , Anestésicos Locais/administração & dosagem , Dexmedetomidina/administração & dosagem , Histerectomia , Intestinos/efeitos dos fármacos , Intestinos/fisiologia , Lidocaína/administração & dosagem , Dor Pós-Operatória/tratamento farmacológico , Recuperação de Função Fisiológica/efeitos dos fármacos , Abdome/cirurgia , Adulto , Idoso , Analgésicos não Narcóticos/farmacologia , Anestésicos Locais/farmacologia , Dexmedetomidina/farmacologia , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Histerectomia/métodos , Infusões Intravenosas , Lidocaína/farmacologia , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
To improve the precision and accuracy of elements and isotopes analysis in traditional Ar-ICP, the addition of nitrogen in ICP has been widely used. The present review focused on the discussions of the basic physical and chemical properties of the Ar-N2 mixed gas inductively coupled plasma and the mechanisms of the special nature of Ar-N2 mixed gas plasma. The applications of Ar-N2 inductively coupled plasma in spectral analysis and mass spectrometry analysis in the past 40 years were summarized. The authors also give an overall outlook on the application of this technology.
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A novel approach for Cd vapor generation was developed on the basis of a plasma-assisted chemical process. The generated Cd vapor was subsequently measured by atomic fluorescence spectrometry. Dissolved Cd species were readily converted into volatile species by reaction with hydrogen in a coaxial thin-film dielectric barrier discharge (DBD) plasma reactor. Both atomic and molecular Cd species were produced when a solution containing Cd(2+) was exposed to hydrogen-containing DBD plasma. Fast and efficient vapor generation of Cd was achieved simply in plain (neutral) water medium. Optimal conditions for the DBD-plasma Cd vapor generator were identified. The performance of this thin-film DBD plasma-chemical vapor generation (CVG) was evaluated through comparison with that arising from the conventional HCl-KBH4 system. The vapor generation efficiency of the proposed method (He-DBD) was found to be superior to the conventional CVG approach. Under the optimized conditions, the detection limits of Cd were found to be from 0.03 ng mL(-1) (Ar-DBD) to 0.008 ng mL(-1) (He-DBD) with a heated quartz tube atomizer (QTA); good repeatability (relative standard deviation (RSD) = 1.4%, n = 5) was obtained for a 1 ng mL(-1) standard. The new thin-film DBD plasma-CVG provides several additional advantages including simple setup, easy coupling with flow injection, low power consumption (≤18 W), cost-effectiveness, and long operation lifetime. The accuracy of the proposed method was validated through analysis of cadmium in reference material of simulated natural water sample GBW(E)080402 and rice reference material GBW10045. The concentration of cadmium determined by the present method agreed well with the reference values.
RESUMO
Cadmium is subject to significant Zr and Mo based oxide/hydroxide interferences in ICP-MS analysis of environmental samples. In this work, a dynamic reaction cell (DRC) technology was used to eliminate these metal oxide/hydroxide interferences. The potentially interfering ions (94)Zr(16)OH(+), (94)Mo(16)OH(+) and (95)Mo(16)O(+) on (111)Cd(+) were oxidized to higher oxides (94)ZrO(2)H(+)/(94)ZrO(3)H(+), (94)MoO(2)H(+)/(94)MoO(3)H(+), and (95)MoO(2)(+)/(95)MoO(3)(+) by O(2) as the reaction gas in DRC. Under the optimized O(2) flow rate (2.0 mLmin(-1)) and DRC rejection parameter q (Rpq, 0.75), the background signal was reduced by up to 100-fold at m/z 111 and the limit of quantitation (LOQ, 10σ) of 0.1 ngg(-1) was obtained. The proposed method was applied to direct analysis of trace Cd in a series of soil and sediment standard reference materials and the satisfactory results showed that it has great potential for the direct determination of trace or ultra-trace levels of cadmium in environmental samples.
Assuntos
Cádmio/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Cádmio/química , Poluentes Ambientais/química , Espectrometria de Massas , Oxirredução , Oxigênio/químicaRESUMO
AIM: To investigate the effects and possible mechanisms of Wy14643 on hepatic ischemia-reperfusion (I/R) injury in rats. METHODS: Thirty male Sprague-Dawley rats weighing 220-280 g were randomly divided into five experimental groups: sham group (G1, n=6): a sham operation was performed (except for liver I/R); I/R-untreated group (G2, n=6): rats underwent liver ischemia for 90 min followed by reperfusion for 4 h; and I/R+Wy14643 groups (G3, G4, G5; n=6): after the same surgical procedure as in group 2, animals were pretreated with Wy14643 at the dose of 1, 5 and 10 mg/kg 1 h before ischemia, respectively. Hepatic ischemia-reperfusion (I/R) was induced by clamping blood supply to the left lateral and median lobes of the liver for 90 min, and atraumatic clamp was removed for 4 h reperfusion. Blood samples and liver tissues were obtained at the end of reperfusion to assess serum and hepatic tissue homogenate aminotransferase (ALT), aspartate aminotransferase (AST), myeloperoxidase (MPO), serum interleukin-1beta (IL-1beta) and tumor necrosis factor alpha (TNF-alpha), as well as activity of superoxide dismutase (SOD) and content of malondialdehyde (MDA) in the hepatic tissue homogenate. RESULTS: Hepatic I/R induced a significant increase in the serum levels of ALT, AST, TNF-alpha, IL-1beta and MPO, as well as the levels of ALT, AST and MDA in the liver tissue homogenate, which were reduced by pretreatment with Wy14643 at the dose of 1, 5 and 10 mg/kg, respectively. The activity of SOD in the liver tissue homogenate was decreased after hepatic I/R, which was enhanced by Wy14643 pretreatment. In addition, serum and liver tissue homogenate ALT and AST in the Wy14643 10 mg/kg group were lower than in the Wy14643 1 mg/kg and 5 mg/kg groups, respectively. CONCLUSION: Wy14643 pretreatment exerts significant protection against hepatic I/R injury in rats. The protective effects are possibly associated with enhancement of anti-oxidant and inhibition inflammation response.
Assuntos
Hepatite/prevenção & controle , PPAR alfa/agonistas , Pirimidinas/uso terapêutico , Traumatismo por Reperfusão/prevenção & controle , Alanina Transaminase/metabolismo , Animais , Aspartato Aminotransferases/metabolismo , Modelos Animais de Doenças , Hepatite/metabolismo , Hepatite/patologia , Interleucina-1beta/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , Pirimidinas/farmacologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/sangueRESUMO
Inductively coupled plasma mass spectrometry (ICPMS) has been successfully used for the detection of element-tagged biomolecules with the advantage of multielement capability. However, this technique cannot be used for microarray detection due to the necessity to dissolve the elemental tags before introducing them to the plasma source. Here, we report the detection of multiple proteins on each spot of the immuno-microarray by laser ablation ICPMS. alpha-Fetoprotein IgG (AFP), carcinoembryonic antigen (CEA), and human IgG, as model proteins, have been detected on the basis of sandwich-type immunoreactions on a microarray with Sm3+-labeled AFP antibody, Eu3+-labeled CEA antibody, and Au-labeled goat-anti-human IgG (GAH) as labeled antibodies. The detection limits were 0.20, 0.14, and 0.012 ng mL-1 (3sigma) with the RSD of 5.7%, 2.6%, and 2.3% at the concentration of 1.0 ng mL-1 for AFP, CEA, and human IgG, respectively. The present detection method permits detecting multiple analytes from each spot of microarray with a spatial resolution at micrometer range, which can alleviate the stress to fabricate high-density arrays. Furthermore, the substrate materials and immobilized proteins do not interfere with the detection. The present technique provides a new strategy for readout of microarray.