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In the present work, computer simulation was performed on a model chemical system where two solutes (denoted as P and Q, respectively) are dissolved in the same solution. Under intermolecular interaction between P and Q, part of P undergoes subtle structural variation and converts into U while part of Q converts into V. The strength of intermolecular interaction can be characterized by the corresponding equilibrium constant K. Our preliminary studies indicate that the S/N ratio of cross peak increases considerably as n increases. Moreover, the S/N ratio of the cross peak from the asynchronous spectra can be improved significantly when the suitable concentrations of P and Q are adopted. This work is helpful for a selection of suitable concentration sequence to maximize S/N ratio of cross peaks in the 2D asynchronous spectra generated by using the DAOSD approach proposed in our previous study so that weak intermolecular interaction can be probed.
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We reported a new super-concentrated hydrochloric acid system prepared by using tri-n-butyl phosphate (TBP)-constructed reversed micelles at ambient temperature and pressure. According to the titration result, the molar ratio of H+ to H2O (denoted as nH+/nH2O) in the super-concentrated HCl range from 0.50 to 1.50 which are higher than that in saturated aqueous HCl bulk solution (0.28). Significant a moment of hydrochloric acid is confined in W/O reversed micelles. Therefore, the behavior and status of HCl are different from those of conventional bluk solution. FTIR spectroscopic results demonstrate that a significant amount of HCl remains in the molecular form rather than being ionized into H+ and Cl-. Thus, super-concentrated HCl provides an extraordinary chemical environment which may have significant influence on certain substances. We found that the color of the solution is reddish brown when copper ion is dissolved in super-concentrated HCl, while the color of the saturated HCl aqueous solution (37 Wt%) containing copper ion is green. That is to say, the copper ions exist in a special state under the unique chemical environment of super-concentrated HCl. UV-Vis-NIR spectra indicate that both d-d transition band and charge transfer transition band of copper ions in super-concentrated HCl solution underwent significant variations. In addition, copper ions also have obvious influence on the hydrogen bond network among HCl in the super-concentrated HCl solution. Remarkable variation is introduced in the H-Cl stretching band in FTIR spectra.
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The authors tried to establish an approach to use acids to convert biomass into a fuel with higher carbon content and lower oxygen content in a zero-energy-consumption fashion. Considering that biomass is composed of monosaccharide, we used aqueous solutions of variation acids including hydrochloric acid, sulfuric acid and perchloric acid to treat 2-deoxy-ribose and fructose at ambient temperature and pressure. Black substances were produced after a period of time when 2-deoxy-ribose and fructose were mixed with aqueous solutions containing 8 mol · L(-1) acids. The black substance was collected and characterized by using elemental analysis, Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Elemental analysis results indicate that the contents of carbon increases significantly in the black substances in comparison with 2-deoxy-ribose and fructose. Moreover, XPS results indicate that the content of oxygen in the black substance undergoes a significant decrease compared with pure 2-deoxy-ribose and fructose. In the XPS spectra, the is peaks of 2-deoxy-ribose, strong sub peak at 286. 05 eV, which is assigned to carbon linked to oxygen directly, dominate in the C is peak envelop. After treatment by HClO4, the peak decreased dramatically. This result also supports the conclusion that the content of oxygen in mono-saccharide is significantly reduced after treatment by acids. In the FTIR spectra of the black substances, strong peaks can be observed around 1 600 cm(-1), indicating that C==C bond is formed in the product. The above results suggest that treatments with acids may be developed as a new zero-energy-consumption approach to convert biomass in a new fuel with improved energy output efficiency.
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Ácidos/química , Biocombustibles , Carbohidratos/química , Carbono/química , Espectroscopía Infrarroja por Transformada de Fourier , Biomasa , Oxígeno , Espectroscopía de FotoelectronesRESUMEN
OBJECTIVE: The present study was designed to evaluate the effects of ulinastatin (UTI) on cardiac dysfunction after cardiopulmonary resuscitation (CPR). METHODS: A total of 48 healthy adult male New Zealand rabbits were untreated for 8 minutes after the induction of ventricular fibrillation (VF) by an external transthoracic alternating current and then treated by CPR. These rabbits were then randomly divided into the control and UTI groups after the return of spontaneous circulation (ROSC) and were observed for 8 hours after the ROSC. Before CPR and after ROSC at 2, 4, and 8 hours, blood samples were collected to determine the levels of tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), malondialdehyde (MDA), cardiac troponin I (cTnI), and N-terminal probrain natriuretic peptide (NT-proBNP), and the left ventricular ejection fraction (EF) was measured by echocardiography. RESULTS: Nineteen of 24 rabbits in the control group and 18 of 24 in the UTI group were successfully resuscitated. The plasma levels of TNF-α, IL-6, MDA, cTnI, and NT-proBNP were significantly increased, accompanying a deceased EF in the control group, but the cotreatment with UTI decreased the plasma levels of TNF-α, IL-6, MDA, cTnI, and NT-proBNP (P < .05), attenuating the myocardial injury and improving the EF in the UTI group. Only 9 of 19 animals in the control group but 14 of 18 animals in the UTI group survived longer than 8 hours (P = .011). CONCLUSIONS: The progression of proinflammatory responses, oxidative stress, and myocardial injury have been linked to the reduced EF after VF/CPR, and the administration of UTI at a cardioprotective dosage preserved the cardiac function after VF/CPR.
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Glicoproteínas/uso terapéutico , Paro Cardíaco/tratamiento farmacológico , Sustancias Protectoras/uso terapéutico , Inhibidores de Tripsina/uso terapéutico , Animales , Biomarcadores/sangre , Análisis de los Gases de la Sangre , Reanimación Cardiopulmonar , Glicoproteínas/farmacología , Paro Cardíaco/sangre , Paro Cardíaco/diagnóstico por imagen , Paro Cardíaco/terapia , Estimación de Kaplan-Meier , Masculino , Sustancias Protectoras/farmacología , Conejos , Distribución Aleatoria , Volumen Sistólico/efectos de los fármacos , Resultado del Tratamiento , Inhibidores de Tripsina/farmacología , Ultrasonografía , Función Ventricular Izquierda/efectos de los fármacosRESUMEN
Background: The number of patients with thrombocytopenia (TCP) is relatively high in intensive care units (ICUs). It is therefore necessary to evaluate the prognostic risk of such patients. Aim: This study investigated the risk factors affecting the survival of patients with TCP in the ICU. Using the findings of this investigation, we developed and validated a risk prediction model. Methods: We evaluated patients admitted to the ICU who presented with TCP. We used LASSO regression to identify important clinical indicators. Based on these indicators, we developed a prediction model complete with a nomogram for the development cohort set. We then evaluated the mode's accuracy using a receiver operating characteristic (ROC) curve, calibration curves, and decision curve analysis (DCA) in a validation cohort. Results: A total of 141 cases of ICU TCP were included in the sample, of which 47 involved death of the patient. Clinical results were as follows: N (HR 0.91, 95% CI 0.86-0.97, P=0.003); TBIL (HR 1.98, 95% CI 1.02-1.99, P=0.048); APACHE II (HR 1.94, 95% CI 1.39, 2.48, P=0.045); WPRN (HR 6.22, 95% CI 2.86-13.53, P<0.001); WTOST (HR 0.56, 95% CI 0.21-1.46, P<0.001); and DMV [HR1.87, 95% CI 1.12-2.33]. The prediction model yielded an area under the curve (AUC) of 0.918 (95% CI 0.863-0.974) in the development cohort and 0.926 (95% CI 0.849-0.994) in the validation cohort. Application of the nomogram in the validation cohort gave good discrimination (C-index 0.853, 95% CI 0.810-0.922) and good calibration. DCA indicated that the nomogram was clinically useful. Conclusion: The individualized nomogram developed through our analysis demonstrated effective prognostic prediction for patients with TCP in ICUs. Use of this prediction metric may reduce TCP-related morbidity and mortality in ICUs.
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BACKGROUND: Venous catheters are widely used in clinical practice, but a drawback of their usage is the increased risk of thrombosis. AIMS: The current study explored the risk factors affecting the formation of thrombosis following venous catheterization and establishes a risk nomogram prediction model for catheter-related thrombosis. METHODS: Univariate and multivariate logistic regression analyses were carried out to identify the independent factors involved in venous catheter thrombosis. These factors were included in the construction of a nomogram. Finally, the C-index and calibration curves were used to validate the nomogram. RESULT: A total of 146 cases were included in the sample, of which 36 were cases of thrombosis. The results of the univariate logistic regression analysis showed that the following were significant factors: age, Acute Physiology and Chronic Health Evaluation scoring system (APACHE II) score, white blood cell (WBC), hematocrit (HCT), international normalized ratio (INR), fibrinogen (FIB), and D-dimer. Multivariate logistic regression analysis was performed, which confirmed that the factors of age (AUC: 0.677, 95% CI: 0.564-0.790), APACHE II score (AUC: 0.746, 95% CI: 0.656-0.837), INR (AUC: 0.743, 95% CI: 0.636-0.849), and D-dimer (AUC: 0.826, 95% CI: 0.750-0.902) were independent variables. Next, a nomogram was constructed using these independent variables for predicting venous catheter thrombosis. Favorable results with C-indexes (0.816; 95% CI: 0.780-0.882) and calibration curves closer to ideal curves indicated the accurate predictive ability of this nomogram. CONCLUSION: The individualized nomogram demonstrated effective prognostic prediction for patients with venous thrombosis.
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Trombosis , Trombosis de la Vena , Humanos , Nomogramas , Estudios Retrospectivos , Trombosis de la Vena/etiología , Trombosis/etiología , Catéteres , Cateterismo/efectos adversosRESUMEN
In situ TLC/FTIR technique has tremendous potential in the analysis of complex mixtures. However, the progress in this technique was quite slow. The reason is that conventional stationary phase has strong absorption in FTIR spectrum and thus brings about severe interference in the detection of samples. To solve the problem, the authors propose to use AgI fine particles as stationary phase of TLC plate. The reasons are as follows: Silver iodide fine particles have no absorbance in an IR region between 4 000 and 800 cm(-1), therefore, the interference caused by IR absorption of stationary phase can be removed. Moreover, silver iodide is stable and insolvable in water and organic solvents and thus it will not be destroyed by mobile phase or react with samples during the TLC separation. To improve TLC separation efficiency and quality of FTIR spectra during the TLC/FTIR analysis, the size of AgI particles should be below 500 nm. We used orthogonal design approach to optimize the experimental condition to AgI particles so that the average size of AgI particles is around 100 nm. No absorption of impurity or adsorbed water were observed in FTIR spectrum of the AgI particles the authors used "settlement volatilization method" to prepare TLC plate without using polymeric adhesive that may bring about significant interference in FTIR analysis. Preliminary TLC experiments proved that the TLC plate using AgI fine particles as stationary phase can separate mixtures of rhodamine B and bromophenol blue successfully. Applications of silver iodide fine particles as stationary phase have bright perspective in the development of in-situ TLC/FTIR analysis techniques.
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In the present work, we prepared nylon 6 crystals via crystallization of nylon from phosphoric acid by using the vapors of ammonium hydroxide as a precipitation regent. Both XRD and FTIR results demonstrate that the obtained nylon 6 sample exhibit characteristic peaks of nylon 6 in gamma form. In addition, treatment of nylon 6 in boiling water for half an hour followed by FTIR and XRD characterization shows that the obtained nylon 6 sample is in gamma form rather than in meta-stable b form. DSC characterization indicates that the nylon 6 sample exhibits two melting peaks (213 and 220 degrees C) when the sample is heated at a heating rate of 10 degrees C x min(-1). The reason for this phenomenon is that the nylon 6 sample has different lamellar thickness. To investigate the thermal behavior of the nylon 6 sample, the sample underwent the following thermal treatment procedure. First, the sample was heated to a pre-set temperature (T(s)) and kept at that temperature for an hour. Subsequently, the sample was cooled down to 100 degrees C at a cooling rate of 1 degrees C x min(-1), and then cooled down to room temperature at a cooling rate of 10 degrees C x min(-1). The treated samples were characterized by FTIR and DSC method. Experimental results show that the treated nylon 6 samples exhibit different crystalline behavior. When T. ranges from 130 to 160 degrees C, no significant changes were observed. When T(s) is 170 degrees C, a small fraction nylon 6 crystals is destroyed and recrystallized into thin lamellae in a form. As a result, a pre-melting peak appears in DSC result. The pre-melting peak moves to higher temperature and its peak area increases significantly upon increasing T(s) from 170 to 198 degrees C. When T(s) amounts to 200 degrees C, the pre-melting peak and the melting peaks 213 degrees C merge into one melting peak and two melting peaks are observed at 212 and 220 degrees C in the DSC results. FTIR spectra indicate that significant amount of crystalline nylon 6 in a form appears but the majority of crystalline phase of the sample is still gamma phase. As T(s) increases from 200 to 209 degrees C, the melting peak at lower temperature moves to higher temperature with increasing its peak area. On the other hand, the melting peak at 220 degrees C decreases in intensity but does not show any peak shift. As T(s) reaches 209 degrees C, the two melting peaks merge into one peak and FTIR results demonstrate that nylon 6 in a form becomes dominate phase in the sample. In the whole heat-treatment process, the gamma phase nylon 6 sample began to transform to a phase at the heat-treatment temperature of 170 degrees C, which is far below the melting point of the original sample (221 degrees C). This is different from the results reported in the literature, which state that gamma phase nylon 6 will not transform to alpha-phase until nylon is melt.
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In situ TLC/FTIR technique has tremendous potential in the analysis of complex mixtures. However, the progress in this technique was quite slow. The reason is that conventional stationary phase such as silica gel etc. has strong absorption in FTIR spectrum and thus brings about severe interference in the detection of samples. To solve the problem, the authors propose to use barium fluoride fine particles as stationary phase of TLC plate. The reasons are as follows: Barium fluoride wafer has been extensively used as infrared window in FTIR experiments and it has no absorbance in an IR region between 4 000 and 800 cm'. As a matter of fact, the atomic mass of barium and fluoride is quite large, thus the normal vibration of BaF2 lattice is limited in far-IR region and low frequency part of mid-IR region. Therefore, the interference caused by IR absorption of stationary phase can be resolved if BaF2 is used as stationary phase of TLC plate. Moreover, BaF2 is quite stable and insolvable in water and most organic solvents and it will not be dissolved by mobile phase or react with samples in TLC separation. Additionally, decreasing the particle size of BaF2 is very important in TLC/FTIR analysis technique. The reason is two-fold: First, decreasing the particle size of stationary phase is helpful to improving the efficiency of separation by TLC plate; second, decreasing the size of BaFz particle can improve the quality of FTIR spectra by alleviating the problem of light scattering. By optimizing the synthetic conditions, fine particles of barium fluoride were obtained. SEM results indicate that the size of the BaF2 particles is around 500 nm. FTIR spectrum of the BaF2 particles shows that no absorption of impurity was observed. Moreover, the elevation of baseline caused by light scattering is insignificant. The authors have developed a new technique named "settlement volatilization method" to prepare TLC plate without polymeric adhesive that may bring about significant interference in FTIR analysis. Preliminary TLC experiments proved that the TLC plate using BaF2 fine particles as stationary phase can separate rhodamine B from methylene blue successfully. Applications of barium fluoride fine particles as stationary phase have bright perspective in the development of new in-situ TLC/FTIR analysis techniques.
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PURPOSE: Vitamin C has shown benefits in patients with sepsis in addition to standard therapy recently. However, further evidence is required to verify the efficacy of vitamin C in clinical practice. This study aimed to investigate the effect of adjunctive intravenous high-dose vitamin C treatment on hospital mortality in patients with sepsis. METHODS: One hundred seventeen patients with sepsis in our department from June 2017 to May 2019 were randomly divided into two groups: the control group (56 cases) and the vitamin C group (61 cases). The control group was treated by the routine and basic therapy with intravenous drip of 5% dextrose and placebo (100 ml/time, 2 times/day), while the vitamin C group was administered intravenously by 3.0 g vitamin C dissolved into 5% dextrose (100 ml/time, 2 times/day) based on the control group. The mortality and efficacy were statistically analyzed and compared between the two groups. RESULTS: The 28-day mortality differed significantly between the control group and the vitamin C group (42.97% vs. 27.93%) (p < 0.05). The changes in the sepsis-related organ failure assessment (ΔSOFA) scores at 72 h after ICU admission (4.2 vs. 2.1), the application time of vasoactive drugs (25.6 vs. 43.8), and the procalcitonin clearance (79.6% vs. 61.3%) differed significantly between groups (p < 0.05). CONCLUSION: The early treatment of sepsis with intravenous high-dose vitamin C in combination with standard therapy showed a beneficial effect on sepsis, in terms of the reduced 28-day mortality, the decreased SOFA score, and the increased clearance rate of procalcitonin.
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Sepsis , Ácido Ascórbico/uso terapéutico , Humanos , Unidades de Cuidados Intensivos , Polipéptido alfa Relacionado con Calcitonina , Pronóstico , Curva ROC , Estudios Retrospectivos , Sepsis/tratamiento farmacológicoRESUMEN
In the present paper, the authors developed a new approach by constructing two-dimensional (2D) UV-Vis/fluorescence heterogeneous synchronous spectrum based on the orthogonal sample design scheme (OSD) developed in our previous works to characterize energy transfer among different lanthanide ions during the luminescence process. The authors use the EuCl3-NdCl3 system as an example. The preliminary experimental results on the 2D synchronous spectra of EuCl3-NdCl3 mixture solutions have demonstrated that cross peaks can be observed among the UV-Vis absorption bands from Nd3+ and fluorescence emission bands from Eu3+. The cross peaks in the 2D synchronous spectra of EuCl3-NdCl3 mixture solutions manifested the interaction between the fluorescence emission from Eu3+ and UV-Vis absorbance from Nd3+, and therefore gives out experimental evidences for the occurrence of energy transfer between Eu3+ and Nd3+ ions. The cross peaks are not from the interaction between the solvent, water, and the solute, Eu3+ or Nd3+ ions. Mathematical analysis performed on 2D synchronous spectra using variable concentration as an external perturbation shows that the orthogonal sample design scheme is indispensable in removing the interfering cross peaks in 2D synchronous spectra. In fact, if the authors detect, respectively, the fluorescence emission spectra of pure Eu3+ solutions and the UV-Vis absorbance spectra of pure Nd3+ solutions, then use these spectra data to construct a series of synthesized spectra of an assumed mixture solution in which Eu3+ and Nd3+ are not mixed together, because Eu3+ and Nd3+ ions are spatially separated, there are no intermolecular interactions that should have occurred. Therefore, there are no cross-peaks that can be observed in the comparative 2D synchronous spectra. The cross peaks in 2D synchronous correlation spectra gives out a new approach to characterizing energy transfer among different lanthanide ions during the luminescence process.
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OBJECTIVE: The role of Ulinastatin in neuronal injury after cardiopulmonary resuscitation has not been elucidated. We aim to evaluate the effects of Ulinastatin on inflammation, oxidation, and neuronal injury in the cerebral cortex after cardiopulmonary resuscitation. METHODS: Ventricular fibrillation was induced in 76 adult male Wistar rats for 6 min, after which cardiopulmonary resuscitation was initiated. After spontaneous circulation returned, the rats were split into two groups: the Ulinastatin 100,000 unit/kg group or the PBS-treated control group. Blood and cerebral cortex samples were obtained and compared at 2, 4, and 8 h after return of spontaneous circulation. The protein levels of tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6) were assayed using an enzyme-linked immunosorbent assay, and mRNA levels were quantified via real-time polymerase chain reaction. Myeloperoxidase and Malondialdehyde were measured by spectrophotometry. The translocation of nuclear factor-κB p65 was assayed by Western blot. The viable and apoptotic neurons were detected by Nissl and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL). RESULTS: Ulinastatin treatment decreased plasma levels of TNF-α and IL-6, expression of mRNA, and Myeloperoxidase and Malondialdehyde in the cerebral cortex. In addition, Ulinastatin attenuated the translocation of nuclear factor-κB p65 at 2, 4, and 8 hours after the return of spontaneous circulation. Ulinastatin increased the number of living neurons and decreased TUNEL-positive neuron numbers in the cortex at 72 h after the return of spontaneous circulation. CONCLUSIONS: Ulinastatin preserved neuronal survival and inhibited neuron apoptosis after the return of spontaneous circulation in Wistar rats via attenuation of the oxidative stress response and translocation of nuclear factor-κB p65 in the cortex. In addition, Ulinastatin decreased the production of TNF-α, IL-6, Myeloperoxidase, and Malondialdehyde.
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Apoptosis/efectos de los fármacos , Reanimación Cardiopulmonar/efectos adversos , Corteza Cerebral/efectos de los fármacos , Glicoproteínas/farmacología , Inhibidores de Tripsina/farmacología , Fibrilación Ventricular/metabolismo , Animales , Western Blotting , Corteza Cerebral/metabolismo , Encefalitis/tratamiento farmacológico , Glicoproteínas/uso terapéutico , Interleucina-6/sangre , Masculino , Malondialdehído/metabolismo , Neuronas/efectos de los fármacos , Neuronas/fisiología , Estrés Oxidativo/efectos de los fármacos , Peroxidasa/metabolismo , Ratas , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa , Reproducibilidad de los Resultados , Factores de Tiempo , Resultado del Tratamiento , Inhibidores de Tripsina/uso terapéutico , Factor de Necrosis Tumoral alfa/sangreRESUMEN
OBJECTIVE: The role of Ulinastatin in neuronal injury after cardiopulmonary resuscitation has not been elucidated. We aim to evaluate the effects of Ulinastatin on inflammation, oxidation, and neuronal injury in the cerebral cortex after cardiopulmonary resuscitation. METHODS: Ventricular fibrillation was induced in 76 adult male Wistar rats for 6 min, after which cardiopulmonary resuscitation was initiated. After spontaneous circulation returned, the rats were split into two groups: the Ulinastatin 100,000 unit/kg group or the PBS-treated control group. Blood and cerebral cortex samples were obtained and compared at 2, 4, and 8 h after return of spontaneous circulation. The protein levels of tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6) were assayed using an enzyme-linked immunosorbent assay, and mRNA levels were quantified via real-time polymerase chain reaction. Myeloperoxidase and Malondialdehyde were measured by spectrophotometry. The translocation of nuclear factor-κB p65 was assayed by Western blot. The viable and apoptotic neurons were detected by Nissl and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL). RESULTS: Ulinastatin treatment decreased plasma levels of TNF-α and IL-6, expression of mRNA, and Myeloperoxidase and Malondialdehyde in the cerebral cortex. In addition, Ulinastatin attenuated the translocation of nuclear factor-κB p65 at 2, 4, and 8 hours after the return of spontaneous circulation. Ulinastatin increased the number of living neurons and decreased TUNEL-positive neuron numbers in the cortex at 72 h after the return of spontaneous circulation. CONCLUSIONS: Ulinastatin preserved neuronal survival and inhibited neuron apoptosis after the return of spontaneous circulation in Wistar rats via attenuation of the oxidative stress response and translocation of nuclear factor-κB p65 in the cortex. In addition, Ulinastatin decreased the production of TNF-α, ...