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The extraction of geraniol from palmarosa oil using hydrotropic solvents was investigated. Palmarosa oil possesses an appealing rose aroma and properties like anti - inflammatory, antifungal, and antioxidant due to the presence of geraniol. The extraction of geraniol from palmarosa oil by using distillation methods like steam dis tillation and fractional distillation was a laborious process. So hydrotropes were tried for extraction. The geraniol yield and purity depend on parameters like concentration of hydrotrope, solvent volume ratio, and time period. Using the Box Benkhem Desig n (BBD), the extraction process was optimized. One of the major advantages of using hydrotropic solvents is that they were classified as green solvents, and recovery of solvents is also possible. To reduce the extraction time probe sonication is carried ou t. Different hydrotropic solvents with probe sonication are done on palmarosa oil by altering various process parameters to study the separation, yield, and purity.
Se investigó la extracción de geraniol del aceite de palmarosa utilizando solventes hidrotrópicos. El aceite de palmarosa posee un atractivo aroma a rosa y propiedades antiinflamatorias, antifúngicas y antioxidantes debido a la pr esencia de geraniol. La extracción de geraniol del aceite de palmarosa mediante métodos de destilación como la destilación por vapor y la destilación fraccionada ha sido un proceso laborioso. Por lo tanto, se probaron los hidrotropos para la extracción. El rendimiento y la pureza del geraniol dependen de parámetros como la concentración del hidrotropo, la relación de volumen del solvente y el período de tiempo. Se optimizó el proceso de extracción usando el diseño Box Benkhem (BBD). Una de las principales v entajas de usar solventes hidrotrópicos es que se clasifican como solventes verdes y también es posible recuperar los solventes. Para reducir el tiempo de extracción, se lleva a cabo una sonda de ultrasonido. Se realizan diferentes solventes hidrotropos co n sonda de ultrasonido en el aceite de palmarosa alterando varios parámetros del proceso para estudiar la separación, el rendimiento y la pureza.
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Plant Oils/chemistry , Cymbopogon/chemistry , Acyclic Monoterpenes/chemistry , Chromatography, GasABSTRACT
Objective To establish the method of fingerprint and content determination of multi-component for Xiangsha Yangwei pill by gas chromatography(GC).Methods The GC fingerprint of Xiangsha Yangwei pill was found,and the peak attribution was carried out.The contents of limonene,eucalyptol,camphor,borneol,bornyl acetate,patchouli alcohol,pogostone,and α-cyperone were determined.Results The fingerprint similarity of 56 batches of Xiangsha Yangwei pill were 0.33-0.99,28 common peaks were confirmed,and 14 known components were identified.Limonene,eucalyptol,camphor,borneol,bornyl acetate,patchouli alcohol,pogostone and α-cyperone showed good linearity within the determined ranges(14.30-286.08,24.52-490.44,16.14-322.88,9.40-187.95,15.39-307.83,25.78-515.60,19.95-398.90,and 24.87-497.30 μg·mL-1).The average recoveries were 101.20％,97.90％,93.97％,94.23％,102.94％,100.54％,99.16％,and 98.31％;with the RSDs were 2.41％,1.48％,1.65％,2.00％,1.93％,2.30％,2.07％,and 2.38％,respectively.The concentrations of eight components were 0.2-959.1,0.3-420.4,1.0-542.6,0.0-64.5,0.0-364.2,0.0-339.6,0.0-130.7,0.0-82.0 μg·g-1,respectively.Conclusion The fingerprint and multi-component determination method can be used for the quality control and evaluation of Xiangsha Yangwei pill.
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Objective To analyze the residual status,transfer behavior,and risk of paclobutrazole in the national mar-ket of Shenmai granules.Methods GC-MS/MS determined the residual amount of paclobutrazol in Shenmai granules,and ANOVA analyzed the distribution characteristics of sample residuals.The transfer rule of paclobutrazol from Ophiopogonis Radix to Shenmai granules was investigated by simulating the production process,and chronic exposure assessment was performed using the point evaluation model.Results The established method can accurately determine the residual amount of paclobutrazol in Shenmai granules.The residual amount of paclobutrazol in 85 batches of Shenmai granules ranged from 0.001 3 to 0.015 8 mg·kg-1,and there was a statistical difference in the residual amount among different enterprise samples.The transfer rate of paclobutrazol from decoction pieces to preparations was 29.8%.The chronic risk quotient(HQc)of paclobutrazol residues in Shenmai granules was 0.000 7%,far lower than 1.Conclusion There is a general presence of paclobutrazol residues in Shenmai granules.The risk assessment results show that the normal dosage of Shenmai granules does not pose an unacceptable risk to the general population.The residual distribution characteristics and process transfer rules can provide a reference for safety risk control in production enterprises.
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Objective To explore the antioxidant capacity of the volatile oil components of the Mongolian medicine Zhenbaowan and the mechanism of action in the treatment of rheumatoid arthritis(RA)by using bioinformatics technology,GC-MS technology,and antioxidant activity experiment.Methods The volatile oil in Zhenbaowan was extracted using water vapor distillation and the volatile oil components were qualitatively analyzed by GC-MS.Based on the results of GC-MS analysis,bioinfor-matics analysis was used to investigate the main components,key targets,and pathways of the volatile oil of Zhenbaowan in pre-venting and treating RA.Meanwhile,the antioxidant activity of the volatile oil was determined and analyzed using the 2,2-Diphen-yl-1-picrylhydrazyl(DPPH)method.Results A total of 115 volatile oil components were identified in Zhenbaowan,of which the top 48 components accounted for 97.66%of the total volatile oil content.Bioinformatics analysis revealed that Zhenbaowan can regulate signal transduction,inflammation,and protein phosphorylation through 147 RA-related targets,and intervene in signaling pathways such as PI3K-Akt,MAPK,and RAS.Molecular docking results showed that the seven main components of Zhenbaowan volatile oil can spontaneously bind to the five core targets.Antioxidant activity tests have proved that the volatile oil of Zhenbaowan has a more significant antioxidant capacity.Conclusion Using GC-MS high-throughput analysis technology combined with bioinformatic analysis and antioxidant activity test,the pharmacodynamic substances and mechanism of action of the volatile oil components of Zhenbaowan,a Mongolian medicine,in the treatment of RA are hypothesized.It provides a theoretical basis for the further study of the volatile oil components of Zhenbaowan.
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Objective To analyze the influence of different processing methods,including frying,ginger frying,and salt frying,on the volatile components of A.fructus.Methods The volatile components in different processed products of A.fructus were detected and analyzed by gas chromatography-mass spectrometry(GC-MS)based on multivariate statistical analysis.After OPLS-DA analysis,the different components were screened under the conditions of VIP＞1.5 and P＜0.05 and were qualitatively searched using the NIST 11 spectral library.Results A total of 49 different components were identified,with 14 components only changing in the seed mass and 22 components changing in the peel.The content of camphor could be significantly reduced in the seed mass after A.fructus was processed and the content of bornyl acetate significantly increased in the peel of frying A.fructus.Salt frying had a great influence on the alkanes in A.fructus,and ginger processing did not only increase the volatile components in ginger,which reflected the complexity of the processing mechanism.Conclusion At present,the specific processing mechanism is not clear,but the experimental results provide theoretical data for the "detoxification and efficiency enhancement" effect of A.fructus processing,reflecting the scientific nature of the processing,enriching the processing theory of A.fructus,and providing a reference for further in-depth research on the activity of different processed products of A.fructus.
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Objective To analyze the metabolic changes of myocardial tissue in rats under acute exposure to macleaya cordata by gas chromatography mass spectrometry(GC-MS),explore forensic identifications of its characteristic metabolites,and verify its toxicological mechanism in poisoning cases.Methods The rats in the exposure group were given 382 mg/kg macleaya extract solution by gavage,and the rats in the control group were given the same dose of solvent.The myocardial samples were analyzed by GC-MS,and pattern recognition was conducted through partial least squares discriminant analysis(PLSDA).The differential metabolites with characteristic changes were identified by variable importance projection(VIP value＞1)and Student's t test(P＜0.01).Results Compared with the control group,21 potential characteristic metabolites were identified.Through KEGG pathway enrichment analysis,it was found that these metabolites were mainly involved in the pathways of glycine,serine and threonine metabolism;pyruvate metabolism and glycerolipid metabolism.Conclusion Through the study of myocardial metabolism in rats exposed to macleaya cordata,we found the information on metabolites closely related to poisoning,which provides new insight and reference for studies on the mechanisms of macleaya cordata poisoning in the field of forensic medicine.
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Objective To assess the value of acute gastrointestinal injury(AGI)and intestinal fatty acid-binding protein(I-FABP)in the prognosis of liver cirrhotic patients with sepsis.Methods Clinical data of 84 liver cirrhosis patients with sepsis who were admitted to the intensive care unit(ICU)of a hospital from September 2020 to March 2023 were analyzed retrospectively,and 41 patients with decompensated liver cirrhosis during the same period were selected as the control group.Serum I-FABP level in patients was determined with enzyme-linked immunosorbent assay(ELISA).Scores of the model of end-stage liver disease(MELD)and sequential organ failure assessment(SOFA)were calculated.AGI was evaluated based on medical records.30-day and 90-day survival was observed.Correlation among variables was analyzed by Spearman correlation.Risk factors for death in patients with liver cir-rhosis and sepsis was determined by multivariate Cox regression analysis.The optimal cut-off value was determined by receiver operating characteristic(ROC)curve,and the diagnostic efficacy was compared through the area under the ROC curve(AUC).Results Both AGI grading and I-FABP level in liver cirrhosis patients with sepsis were higher than those in the control group(both P＜0.05).I-FABP level was correlated with procalcitonin(PCT),MELD,and SOFA scores in patients with liver cirrhosis and sepsis(all P＜0.05).AGI grading was positively cor-related with SOFA score(P=0.038).The 30-day and 90-day mortality of patients in the liver cirrhosis with sepsis group were 25.0％(n=21)and 35.7％(n=30),respectively.Multivariate Cox regression analysis showed that baseline I-FABP and SOFA scores were independently correlated with 30-day and 90-day survival,and the I-FABP quartile showed good prognostic differentiation efficacy.ROC curve showed that I-FABP could significantly improve the predictive effect of SOFA score on the prognosis of patients.Conclusion AGI grading and I-FABP level in liver cirrhosis patients with sepsis are elevated significantly.Serum I-FABP is associated with the prognosis of patient and can improve the predictive efficacy of SOFA score for survival.
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Objective To explore the impact of pre positioned nasopharyngeal airway combined with high head pre inhalation of oxygen on lung oxygenation and blood gas analysis indicators in morbid obese patients undergoing laparoscopic weight loss surgery.Methods 100 morbid obesity patients from January 2020 to April 2022 planned to undergo elective laparoscopic weight loss surgery were selected as the study subjects.All the patients were divided into two groups according to the random number table method:group A with a head height of 25° and a pre installed nasopharyngeal airway;group B with a head height of 25° and no pre installed nasopharyngeal airway,with 50 patients in each group.Two groups were pre oxygenated for 3 min before undergoing intravenous anesthesia to induce tracheal intubation.Observe and record the pH value,partial pressure of oxygen in arterial blood(PaO2),partial pressure of carbon dioxide(PCO2),partial pressure of oxygen in arterial blood/fractional concentration of inspiratory oxygen(PaO2/FiO2)as well as the ratio of arterial pressure to alveolar oxygen partial pressure(a/APO2)of the two groups of patients who breathed air(T0)after entering the room,ventilated with mask positive pressure for 3 min(T1),and intubated with trachea for 3 min(T2).Record plateau pressure(Pplat),peak airway pressure(Ppeak),and dynamic lung compliance(Cdyn)at T1,T2,and 5 min after pneumoperitoneum(T3).Record the time for percutaneous arterial oxygen saturation(SpO2)to decrease to 92.0%under different artificial ventilation after tracheal intubation,the time for SpO2 to recover to 96.0%after resumption of ventilation,and the occurrence of adverse reactions.Results Compared with Group B,at time point T1,Group A showed a decrease in PCO2 and an increase in PaO2,with statistically significant differences(all P<0.05);Compared with T0,at time points T1 and T2,PaO2/FiO2 and PCO2 in the two groups were increased,while a/APO2 decreased(all P<0.05).At T1 time point,Pplat and Ppeak in Group A were lower than those in Group B,while Cdyn was higher than that in Group B,with statistical significance(P<0.05);Compared with T1 time point,at T2 and T3 time point,Pplat and Ppeak in Group A increased,while Cdyn decreased,with statistically significant differences(all P<0.05);Compared with T1,Ppeak increased in B groups at T2 time point(P<0.05),while Pplat and Ppeak increased in T3 time point,and Cdyn decreased in B group,with statistical significance(all P<0.05).Compared with Group B,Group A had a longer time for SpO2 to decrease to 92.0%and a shorter time for SpO2 to recover to 96.0%(P<0.01).Conclusion The combination of pre positioned nasopharyngeal airway and high head pre inhalation of oxygen can effectively improve acute respiratory obstruction during induction of general anesthesia insertion in morbid obesity patients,and extend the duration of no ventilation.
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OBJECTIVE To investigate the effect and mechanism of acute exposure to sodium cyanide(NaCN)on brain nerve damage induced by closed hypoxia in mice.METHODS ① Mice were randomly divided into hypoxia+NaCN 0(hypoxia control group),2.56,3.8,and 5.1 mg·kg-1 groups.After ip adminis-tration of different concentrations of NaCN,the mice were immediately placed into a closed hypoxic tank and the hypoxia survival time was observed.②Mice were divided into normal control,NaCN 3.8 mg·kg-1,hypoxia(30 and 60 min)and NaCN 3.8 mg·kg-1+hypoxia(30 and 60 min)groups.After grouping,the pH,oxygen saturation(sO2),oxygen tension(pO2)and carbon dioxide partial pressure(pCO2)of arterial blood of mice were detected using an arterial blood gas analyzer.The cortical cerebral blood flow of mice was detected using a laser speckle imager.The dry and wet brain tissue were weighed separately,and the brain moisture content was calculated.The kit was used to detect the activity of total superoxide dismutase(T-SOD)and the content of malondialdehyde(MDA)in the hippocampus.TUNEL staining was used to detect the apoptosis rate of cells in the hippocampus.HE staining was used to detect path-ological changes in the hippocampus.RESULTS ①Compared with the hypoxic control group,the sur-vival time of mice in the hypoxic+NaCN groups was significantly prolonged(P<0.01).②Compared with the normal control group,the hypoxia 30 min group showed upregulation of arterial blood p CO2(P<0.05),downregulation of p O2(P<0.05).The hypoxia 60 min group showed upregulation of arterial blood p CO2(P<0.05)and downregulation of cortical cerebral blood flow(P<0.05).In the NaCN 3.8 mg·kg-1 group,arterial blood p O2 and s O2 were significantly downregulated(P<0.05),so was cortical cerebral blood flow(P<0.01),but MDA content and T-SOD activity were significantly upregulated(P<0.01),and the brain moisture content was increased(P<0.01).Compared with the hypoxia 30 min group,s O2 and p O2 of arterial blood in the NaCN+hypoxia 30 min group were significantly upregulated(P<0.05),while p CO2 was significantly downregulated(P<0.05).Compared with the hypoxia group at corresponding time points,the NaCN+hypoxia 30 or 60 min groups showed significant downregulation of cerebral blood flow(P<0.01),significant upregulation of MDA content and T-SOD activity(P<0.01),and signifi-cant upregulation of brain moisture content(P<0.01).HE staining results showed that the NaCN 3.8 mg·kg-1 group and the NaCN+hypoxia group(30 or 60 min)showed significant cell swelling and vacuolization in cells in the hippocampal tissue,a decrease in the number of neurons,nuclear pyknosis and deep staining.TUNEL fluorescence results showed that the NaCN 3.8 mg·kg-1 group significantly increased the apop-tosis rate of the mouse hippocampus compared with the normal control group(P<0.05).The NaCN+ hypoxia 30 and 60 min groups significantly increased the apoptosis rate of the mouse hippocampus compared with the hypoxia group at corresponding time points(P<0.05).CONCLUSION NaCN can exacerbate hypoxia induced decrease in cerebral blood flow,oxidative stress in brain tissue,and neuro-nal apoptosis in mice,thereby reducing oxygen consumption in closed hypoxic tanks and prolonging their survival time.The mechanism is related to reduced utility of cell oxygen,delaying CO2 accumulation and increasing free oxygen in vivo.
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Objective To analyze and identify the volatile constituents in different parts(flowers,stems and leaves)of Huai chrysanthemumin,and to lay a theoretical foundation for the comprehensive utilization for it.Methods The volatile oil in different parts of Huai chrysanthemumin were extracted by hydrodistillation,respectively.Their constituents were analyzed by gas chromatography-mass spectrometry(GC-MS).The compounds were identified by library search and literature screening.The relative percentage of each compound was obtained by the area normalization method.The differences in their chemical compositions were analyzed by Venn diagram,principal component analysis(PCA)and cluster heat map analysis.Results A total of 62 volatile chemical components were identified from different parts of Huai chrysanthemumin,including monoterpenes,sesquiterpenes,and their derivatives,as well as a small amount of aliphatic compounds.32,42 and 40 volatile components were detected from the flowers,stems and flowers,respectively.Furthermore 17 volatile components were shared by three parts,whereas 5,6 and 16 volatile components were unique to the flowers,stems and leaves,respectively.The results of stoichiometric analysis showed that both PCA and cluster heat map analysis could separate the flowers,stems and leaves,and their volatile components were different.Conclusion The types and contents of the volatile oil in the stems,leaves and flowers of Huai chrysanthemumin have certain variability,which provide a scientific basis for the further medicinal or industrial exploitation of different parts of Huai chrysanthemumin.
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Objective To determine the related substances in the pharmaceutical excipient triacetin by gas chromatography(GC).Methods Rtx-1701 and DB-1701 chromatographic column(30 m×0.25 mm,0.25 μm)was used,with nitrogen as the carrier gas,the flow rate was 1.5 mL/min,the inlet temperature was 200℃,the hydrogen flame ionization detector was used,the temperature of the measuring instrument was 250℃,and the program heating was used.Results Under this chromatographic condition,each substance could be effectively separated,and showed good linearity at 2-40 μg/mL(r>0.99).The recovery rates of acetic acid,glycerol,1-monoglyceryl acetate,1,2-diglyceryl acetate and 1,3-diglyceryl acetate were 100.7%(RSD=3.12%),95.1%(RSD=3.66%),99.43%(RSD=4.62%),103.66%(RSD=5.88%)and 103.15%(RSD=4.17%)(n=6),respectively.Conclusion This method has high accuracy and good reproducibility,which can be used for the determination of related substances in the triacetin,and provides a reference for the quality standard of triacetin.
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Objective:To explore the effects of ventilator parameters on the compliances of chest and lung,and arterial blood gas indicators of patients with acute exacerbation of chronic obstructive pulmonary disease(AECOPD)when biphasic positive airway pressure(BiPAP)ventilation treated AECOPD patients at acute exacerbation period.Method:A total of 78 AECOPD patients who underwent non-invasive ventilation treatment by using BiPAP ventilators in Xinjiang Cardiovascular and Cerebrovascular Hospital from April 2020 to April 2021 were selected.The common range of inspiratory positive airway pressure(IPAP)was 10-25 cmH2O.Based on the specific situation and adjustment of clinical needs of patients,this study set"<15 cmH2O"as the low IPAP group(n=34),and set"≥15 cmH2O"as the high IPAP group(n=44)to analyze the correlation between IPAP of BiPAP ventilator parameters and the therapeutic effects,chest lung compliances and arterial blood gas indicators of patients.Results:The rate of therapeutic effect of patients in the high IPAP group was 93.48%,which was significantly higher than 71.88%of the low IPAP group,and the difference between the two groups was statistically significant(x2=6.766,P<0.05).Before treatment,there were no statistically significant differences in indicators included chest compliance(CTh),lung compliance(CL)and total compliance(Ct)between the two groups(P>0.05).After treatment,the Ct,CL and CTh of patients in the high IPAP group were significantly higher than those in the low IPAP group,and the differences between the two groups were statistically significant(t=2.508,2.027,2.185,P<0.05),respectively.There was no statistically significant difference in arterial oxygen partial pressure(PaO2)value between the two groups before used mechanical ventilation(P>0.05).The PaO2 values of patients at 2,4,6 and 8h of using mechanical ventilation in the high IPAP group were significantly higher than those in the low IPAP group,and the differences between different groups were statistically significant(t=8.531,5.296,3.264,4.623,P<0.05),respectively.Both two groups of patients showed a significant increase in inflammatory mediators such as matrix metalloproteinase-9(MMP-9)and interleukin-8(IL-8)during occurring disease.After treatment,the levels of the two mediators decreased,and the high IPAP group was significantly lower than that of low IPAP group(t=2.251,5.484,P<0.05),respectively.The incidence of abdominal distension in patients of high IPAP group was 20.45%,which was significantly higher than 5.88%of low IPAP group,and the difference between groups was statistically significant(x2=3.623,P<0.05).Conclusion:The IPAP of BiPAP ventilator parameters has effect on chest lung compliance,arterial blood gas analysis and inflammatory indicators in AECOPD patients.High IPAP can improve therapeutic effect,and improve chest lung compliance and arterial blood gas analysis,but can easily cause adverse reactions such as abdominal distension.
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[Objective]To analyze the chemical components of the compound essential oil for mosquito repellent,which was composed of Menthae haplocalyx Briq.,Spirodela polyrrhiza(L.)Schleid,Acorus tatarinowii Schott and Rosmarinus offiicinalis L.,and to evaluate its repellent effect.[Methods]The chemical components of the compound mosquito repellent essential oil were analyzed by gas chromatography-mass spectrometer(GC-MS),and the repellent activity of the essential oil against adult Aedes albopictus was evaluated according to the"Efficacy Test and Evaluation of Space Repellent Products(Y-tube Method)".[Results]Fifty-eight main volatile components were identified,accounting for 98.28％of the total components of essential oil,eighteen terpenes(44.99％),nine alkenes(20.27％),five esters(14.07％),eight aromatic hydrocarbons(12.00％),seven alkanes(3.48％),nine alcohols(2.78％),two ketones(0.69％).The percent repellency(PR)of the compound mosquito repellent essential oil against Aedes albopictus was more than 90％on average.[Conclusion]There were many chemical components in the compound mosquito repellent essential oil.There may be a variety of chemical components such as menthol,menthone,α-pinene,etc,which had a repellent effect on Aedes albopictus,and the average repellent effect reached the A level.
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Background Propylene glycol monomethyl ether (PGME) is a widely used organic solvent. It exists in the form of two isomers in the workplace, which will cause adverse effects such as eye and upper respiratory tract irritation in workers. However, there is still a lack of standard detection methods for simultaneous detection of two isomers of PGME in China. Objective To establish a solvent desorption-gas chromatographic method for two isomers of PGME [1-methoxy-2-propanol (α-PGME), 2-methoxy-1-propanol (β-PGME)] in workplace air. Methods A method of solvent desorption-gas chromatography for α-PGME and β-PGME in workplace air were proposed. Air samples were collected with solvent desorption activated carbon tubes, desorbed using a desorption solution of dichloromethane/methanol (85:15), and then separated on a free fatty acid phase (FFAP) fused silica capillary chromatography column , detected with a flame ionization detector (FID), and quantified by peak area. Standard evaluation protocol was followed to obtain key indicators: standard curve, limit of detection, lower limit of quantification, relative standard deviation (RSD) that measures precision, and spiked recovery of sample solutions that measures accuracy. Desorption efficiency, sampling efficiency, and adsorption capacity tests were conducted, sample stability was evaluated using spiked activated carbon tube preservation test, and interference test was also assessed. The developed method was then applied to field air sample testing. Results In this method, using dichloromethane/methanol (85:15) as the sample desorption solution, the quantitative detection ranges of α-PGME and β-PGME were 0.95-923.0 μg·mL−1 and 0.97-912.0 μg·mL−1 with both correlation coefficients of 0.999 9, the method limits of detection were 0.28 µg·mL−1 and 0.29 µg·mL−1, and the lower limits of quantification were 0.95 µg·mL−1 and 0.97 µg·mL1, respectively. The lowest concentrations detected were both 0.19 mg·m−3, and the lowest concentrations quantified were 0.63 mg·m−3 and 0.65 mg·m−3, respectively, under the conditions of sampling volume of 1.5 L and the volume of desorption solution of 1.0 mL. The intra-batch precisions for α-PGME and β-PGME were 2.8%-4.9% and 2.8%-5.1%, the inter-batch precisions were 4.2%-5.7% and 4.5%-5.9%, the spiked recoveries were 98.8%-100.3% and 96.4%-102.9%, and the desorption efficiencies were 92.7%-97.3% and 92.2%-98.1%, respectively. The average sampling efficiency was 100%, and the samples could be stored at room temperature (25-30 ℃) for at least 7 d and at 4 ℃ for at least 15 d. The adsorption capacities of the activated carbon sampling tube for α-PGME and β-PGME were greater than 13.9 mg and 2.7 mg (100 mg of activated carbon adsorbent), respectively. Possible co-existing components in workplace did not interfere with the determination of α-PGME and β-PGME. The short-time exposure concentrations of α-PGME and β-PGME in the spray painting unit of an automobile manufacturing company were determined to be 18.69 mg·m−3 and 2.19 mg·m−3, and the time-weighted average concentrations were 6.03 mg·m−3 and 1.08 mg·m−3 respectively. Conclusion This method is accurate, precise and suitable for on-site monitoring of the two isomers of PGME in workplace air.
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AIM: To analyze changes in the ocular surface parameters of keratoconus after long-term wearing of rigid gas permeable contact lens(RGPCL).METHODS:Prospective case study. A total of 113 keratoconus patients(213 eyes)fitted with RGPCL in the optometry center of Gansu Provincial Hospital from January 2018 to January 2022 were included. They were divided into three groups according to the severity of keratoconus, including 42 cases(80 eyes)in mild keratoconus group, 54 cases(102 eyes)in moderate keratoconus group and 17 cases(31 eyes)in severe keratoconus group. Furthermore, the non-invasive tear break-up time(NIBUT), non-invasive tear meniscus height(NITMH), red eye index, lipid layer thickness, fluorescent corneal staining, meibomian gland secretory function, Schirmer I test and ocular surface disease index(OSDI)scores were observed by Keratograph analyzer before and after wearing RGPCL for 1 wk, 1, 3, 6, 12 mo, respectively.RESULTS: There were no statistical significance in the age, NIBUT, NITMH, lipid layer thickness, meibomian gland secretory function and Schirmer I test among the three groups(P>0.05), while there were statistical significance in the sphere, cylinder, spherical equivalent, best corrected visual acuity(BCVA), non-contact intraocular pressure(IOPNCT), anterior, posterior corneal surface Kmax, corneal surface thickness at the thinnest point, eye redness index, fluorescent corneal staining, and OSDI(P<0.05). In the mild keratoconus group, NIBUT had statistical differences at 3, 6 and 12 mo after wearing RGPCL(P<0.05), NITMH had statistical differences in 6 and 12 mo(P<0.05), the eye redness index, fluorescent corneal staining and OSDI scores had statistical differences in 1 wk and 1 mo(P<0.05), and lipid layer thickness and meibomian gland secretory function had statistical differences in 12 mo(P<0.05). In the moderate keratoconus group, there were statistical differences in NIBUT at 6 and 12 mo after wearing lenses(P<0.05); there were statistical differences in the NITMH, lipid layer thickness and meibomian secretory function at 12 mo after wearing lens(P<0.05); there were statistical differences in the eye redness index at 1 wk, 1 and 3 mo after wearing RGPCL(P<0.05); there were statistical differences in the fluorescent corneal staining at 1 wk after wearing RGPCL(P<0.05); there were statistical differences in the OSDI at 1 wk and 1 mo after wearing RGPCL(P<0.05). In the severe keratoconus group, there were statistical differences in the NIBUT, NITMH and eye redness index at 1 wk, 1, 3, 6 and 12 mo after wearing RGPCL(P<0.05); there were statistical differences in the lipid layer thickness at 6,12 mo after wearing RGPCL(P<0.05); there were statistical differences in the fluorescent corneal staining and OSDI scores at 1 wk, 6 and 12 mo after wearing RGPCL(P<0.05); there were statistical differences in the meibomian secretory function at 6 and 12 mo after wearing RGPCL(P<0.05); and there were statistical differences in the Schirmer I test at 12 mo after wearing RGPCL(P<0.05).CONCLUSION: Long-term wearing of RGPCL can affect the ocular surface microcirculation in keratoconus patients, thus making differences in patients subjective. However, it has no significant impact on the visual quality of patients. Therefore, long-term wearing of RGPCL is safely to control the progression of keratoconus.
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A derivatizaton method combined with gas chromatography-mass spectrometry(GC-MS)was established for detection of isobutyl chloroformate(IBCF)residue in active pharmaceutical ingredient of agatroban.The extraction and derivatization reagents,derivatization time,qualitative and quantitative ions were selected and optimized,respectively.The possible mechanism of derivatization and characteristic fragment ions fragmentation were speculated.The agatroban samples were dissolved and extracted by methanol,and the residual IBCF was derived with methanol to generate methyl isobutyl carbonate(MIBCB).After 24 h static derivatization at room temperature,IBCF was completely transformed into MIBCB,which could be used to indirectly detect IBCF accurately.The results showed that the linearity of this method was good in the range of 25-500 ng/mL(R2=0.9999).The limit of detection(LOD,S/N=3)was 0.75 μg/g,and the limit of quantification(LOQ,S/N=10)was 2.50 μg/g.Good recoveries(95.2%-97.8%)and relative standard deviations(RSDs)less than 3.1%(n=6)were obtained from agatroban samples at three spiked levels of IBCF(2.50,25.00,50.00 μg/g),which showed good accuracy of this method.Good precision of detection results was obtained by different laboratory technicians at different times,the mean value of spiked sample solution(25.00 μg/g)was 24.28 μg/g,and the RSD was 2.1%(n=12).The durability was good,minor changes of detection conditions had little effect on the results.Under the original condition and conditions with initial column temperature±5℃,heating rate±2℃/min,column flow rate±0.1 mL/min,the IBCF content of spiked sample solution(25.00 μg/g)was detected,the mean value of detection results was 24.16 μg/g,and the RSD was 2.2%(n=7).Eight batches of agatroban samples from two manufacturers were detected using the established method,and the results showed that no IBCF residue was detected in any of these samples.The agatroban samples could be dissolved by methanol,and then the IBCF residue could be simultaneously extracted and derived with methanol as well.This detection method had the advantages of simple operation,high sensitivity,low matrix effect and accurate quantification,which provided a new effective method for detection of IBCF residue in agatroban.
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Objective To investigate the characteristic volatile organic compounds(VOCs)in exhaled breath and their diagnostic value in mice with early stage radiation injury.Methods The thermal desorption gas chromatography-mass spectrometry(TD-GC/MS)technique was used to analyze VOCs in exhaled breath of irradiated mice by 60Coγ-ray with 800 cGy.The characteristic VOCs in the early stage of radiation injury were identified,and a diagnostic model was established.Results The 30-day survival rate of mice was 4.2%.There were significant differences in characteristic VOCs at 7 hours after radiation injury,and thirty characteristic VOCs related to early-stage radiation injury were identified.The diagnostic value of differential metabolites in mice after irradiation was evaluated via the ROC curve,and the area under the ROC curve(AUC)of a single compound exceeded 0.8.The diagnostic model was constructed by screening 9 potential biomarkers of exhalation through Fisher discriminant analysis,and its sensitivity and specificity were close to 100%.Conclusion Analysis of VOCs in exhaled breath is expected to provide a non-invasive diagnostic method for early screening and diagnosis of radiation injury.
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Objective:To determine the effect of gastrodin(GAS)on toll-like receptor 4(TLR4)expression in mi-croglia after hypoxic-ischemic brain damage.Methods:Hypoxia-ischemic brain damage(HIBD)model was established in neonatal rat in vivo.Thirty 3 d SD rats of were randomly divided into there groups:Sham group,HIBD model group,HIBD model+gastrodin intervention group(HIBD+G).Oxygen glucose deprivation(OGD)model was established in BV2 cells in vitro,Control group(Control),oxygen glucose deprivation group(OGD),OGD+gastrodin intervention group(OGD+G)were randomly set in vitro.Both Western Blot and immunofluorescence staining techniques were used to detect the expression of TLR4 in cells of each group in vitro and in the left corpus callosum region in vivo.Results:The expression of TLR4 was significantly increased in OGD-induced microglia.After gastrodin intervention,TLR4 expression was decreased significantly(P＜0.05).Conclusion:GAS can inhibit the expression of TLR4 in activated microglia and thus play a neuroprotective role in HIBD.
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@#Objective To investigate the treatment of neonatal respiratory distress syndrome by less invasive surfactant administration(LISA)clinical efficacy,complications and influence on blood gas analysis.Methods A total of 100 cases of neonatal respiratory distress syndrome requiring pulmonary surfactant(PS)tracheal injection therapy and admitted to the Jinhua Central Hospital between December 1st 2019 and August 1st 2022 were randomly assigned into treatment group(50 cases)and control group(50 cases).The treatment group of children received PS treatment using LISA technology,while the control group of children received PS treatment using tracheal intubation tracheal instillation PS extubation followed by intubation-surfactant-extubation technology.The clinical treatment effect,blood gas analysis,non-invasive ventilation time,length of hospitalization,and incidence of complications were compared between the two groups.Results The total effective rate of treatment in the treatment group was higher than that in the control group;After 1 hour of PS treatment,the oxygen partial pressure and blood oxygen saturation of the treatment group were higher than those of the control group,while the carbon dioxide partial pressure was lower than that of the control group.The non-invasive assisted ventilation time of the treatment group was shorter than that of the control group.The incidence of bronchopulmonary dysplasia was lower than that of the control group.Their difference were statistically significant(P<0.05).Conclusion The use of LISA technology for PS treatment of NRDS can improve blood gas indicators,shorten non-invasive ventilation time,improve diagnostic and therapeutic effects,reduce the risk of bronchopulmonary dysplasia,and do not increase the incidence of complications such as tracheal mucosal injury and pulmonary hemorrhage in children.