1.Determination of Metal Ions in Environmental Samples by Matrix-Assisted Microwave Induced Plasma Surface Sampling Atomic Emission Spectrometry
Chinese Journal of Analytical Chemistry 2015;(9):1306-1312
A novel method for the determination of metallic elements in environmental samples was developed based on the matrix-assisted plasma surface sampling atomic emission spectrometry ( AES system) . A piece of filter paper was used as sample substrate. By direct interaction of the plasma tail plume with the filter paper surface, the filter paper absorbed energy from the plasma source and released combustion heating to the analytes originally present on its surface, thus to promote the atomization and excitation process. Surface sampling was performed in both cases of liquid and solid state analytes. Therefore, no flow injection system was required and sample pretreatment process was simplified. The proposed method provides several advantages, including fast analysis speed ( about 240 samples/h ) , little sample consumption (μL or μg level) , simplicity in instrument design, and also ease of system operation. These advantages made it attractive as a potential miniaturized AES system for in situ and high-throughput elemental analyses. Quantitative analysis of metal ions were achieved in this study for elements Ag, Au, Ba, Cd, Cr, Cu, Eu, La, Mn, Ni, Pb, Sr and Y. Under optimal conditions, the LOD values of the 13 elements ranged from 1. 0 to 88 μg/L. The repeatability, expressed as relative standard deviation ( RSD) from 10 replicates, ranged from 2. 3% to 6. 8%. To validate the proposed method, the system was employed to determine metal elements in standard reference materials of environmental samples. The content of each element was well in agreement with the certified values.
2.Changes of vasocative intestinal peptide neurons in the myenteric plexus of gastric antrum in rats with se-vere acute pancreatitis
Cheng ZHANG ; Zhong LIN ; Yuan YUAN ; Zehui DUAN
Journal of Medical Postgraduates 2014;(9):932-935
Objective Patients with severe acute pancreatitis ( SAP) always suffer decrease in gastrointestinal motility , even gastrointestinal failure.The article aimed to investigate the changes of vasoactive intestinal peptide (VIP) in the myenteric plexus of the gastric antrum in rats with severe acute pancreatitis ( SAP) complicated by gastrointestinal dysmotility . Methods Twenty Sprague Dawley rats were randomly allocated into two groups:control group and SAP group .Acute pancreatitis was induced by intraductal infu-sion of 5%sodium taurodeoxycholate .24 h after operation , records were made on pathological evaluation of pancreatic lesion , amylase, C-reactive protein ( CRP) , gastric emptying rate and the percentage of VIP neurons in the total neurons . Results Compared with the control group, the gastric emptying rate in the SAP group was significantly lower ([31.49 ±3.96]% vs [70.99 ±1.82]%).The score of pancreatic lesion, amylase, CRP and the percentage of VIP neurons was significantly higher ([14.63 ±1.06]score vs [1.60 ± 0.52]score, [2061.25 ±434.86]U/L vs [360.20 ±30.29]U/L, [140.10 ±17.07]μg/mL vs [35.71 ±6.43]μg/mL, [22.45 ± 4.10]%vs [10.72 ±1.92]%)(P<0.05). Conclusion Plas-ticity took place in VIP neurons in the myenteric plexus of gastric an-trum in rats with SAP complicated by gastrointestinal dysmotility , which was connected with neural mechanism underlying SAP compli-cated by gastrointestinal dysmotility .
3.Practice and experience on performing a better medical ultrasound teaching for undergraduate medical students
Lijun YUAN ; Yunyou DUAN ; Tiesheng CAO
Chinese Journal of Medical Education Research 2015;(1):38-41
Currently, medical ultrasound teaching focuses on the delivering the image infor-mation itself, while its connection with basic medicine and clinical medicine is neglected. Such a teaching method is not good for students to establish a systemic view. To conduct the ultrasound medi-cine education effectively in undergraduate students, we have tried some reforms, including: perform-ing diseases or problem based teaching, integrating basic medicine, ultrasound medicine and clinical medicine throughout the whole teaching process, providing as many practice opportunities as possible for the graduates and integrating the ultrasound imaging with other medical imaging modalities. The practice shows that with the reform, the students have a better understanding of ultrasonic knowledge itself, a better grasp of the whole medical knowledge structure, and also have a preliminary impression on how to diagnose the disease through reasonable application of different treatments. In addition, students have more passion for study.
4.A new selaginellin derivative from Selaginella pulvinata.
Yuan CAO ; Yongping WU ; Jinao DUAN
Acta Pharmaceutica Sinica 2015;50(2):199-202
Abstract: A new selaginellin derivative named as selaginellin S (1) was isolated from the whole plants of Selaginella pulvinata (Hook. et Grev.) Maxim. (Selaginellaceae), together with a known one (selaginellin M, 2). Compounds 1 and 2 were separated and purified by silica gel and Sephadex LH-20 column chromatography. Their structures were determined on the basis of extensive spectroscopic analysis including IR, MS, 1D and 2D NMR experiments, as well as ECD calculations. Compound 1 is a key intermidiant in the biosynthesis pathway of selaginellins. Compound 2 is first reported in this plant.
5.Clinical efficacy of norepinephrine and dopamine in the treatment of shock and the impact on renal function
Guangrui ZHAO ; Tuanzhou DUAN ; Yuan REN
Chinese Journal of Primary Medicine and Pharmacy 2014;21(6):882-883
Objective To compare the effect of dopamine and norepinephrine in the treatment of shock and the effect on renal function.Methods 100 shock patients were randomly divided into norepinephrine group and dopamine group,50 cases in each group.On the basis of other anti-shock treatment,norepinephrine or dopamine was used in group A and group B.The mortality of the 7th day and urea nitrogen(BUN),creatinine values (CRE) 12h,72h after treatment were observed.Results There was no significant difference between two groups in the 7th day mortality (x2 =0.765,P > 0.05).However,the proportion of arrhythmia in dopamine group was 34%,which was significantly higher than the norepinephrine group(16%) (x2 =3.84,P < 0.05).After treatment,the BUN and CRE levels in both two groups recovered,the norepinephrine group recovered better than the dopamine group (P < 0.05).Conclusion Norepinephrine and dopamine in the treatment of shock has similar clinical effect,but norepinephrine is more effective in the improvement of renal function compared with dopamine.
7.Diagnosis and differential diagnosis of Doppler ultrasonography in traumatic arteriovenous fistula
Yunyou DUAN ; Xi LIU ; Lijun YUAN
Chinese Journal of Ultrasonography 2003;0(11):-
Objective To observe characteristic imaging of traumatic arteriovenous fistulas(TAVF) and to evaluate the methods of differential diagnosis of TAVF by Doppler ultrasonography. Methods Eleven patients suffering from TAVF were selected to have the examination of Doppler ultrasonography. The blood flow of arteriovenous fistulas, diameter, morphology and blood flow character of affected vessels were observed. Spectral of fistula and affected vessels were analyzed and compared with the healthy side. Results Localization of arteriovenous fistulas was observed directly in eight patients, which presented as intercepted wall of the affected vessels and irregular mosaic flashes flowing towards enlarged vein from artery. Pulsed wave Doppler showed unilateral continuant spectral with maximum velocity 300-390 cm/s when sampled in the fistula. Spectral analysis of proximal arteries of the fistula revealed high velocity and low resistance. Arterialized flow pattern was observed in affected veins. Proximal veins of the fistula revealed arterialized spectral with high velocity and low resistance. Reversed centrifugal blood flow was observed in the distal veins of the fistulas in 4 cases. Conclusions Unilateral shunt in both diastole and systole in the fistula and arterialized flow with high velocity in veins are characteristic presentation of TAVF. Color Doppler ultrasonography has great value in confirming diagnosis and differential diagnosis of TAVF.
8.THE RESPONSE AND RELATIONSHIP OF RAT SPINAL TRIGEMINAL NUCLEUS ASTROCYTES AND NEURONS TO PAIN INDUCED BY SUBCUTANEOUS FORMALIN INJECTION
Hua YUAN ; Li DUAN ; Zhiren RAO
Acta Anatomica Sinica 2002;0(06):-
Objective To investigate the responses of neurons and astrocytes within rat′s spinal trigeminal nucleus(Sp5C) following nocuous pain stimulation induced by subcutaneous formalin injection into the unilateral upper lip. Methods By means of anti\|phospholipase(PLC),anti\|Fos protein and anti\|glial fibrillary acidic protein(GFAP) immunohistochemical method,the distribution of reactive neurons and astrocytes in the Sp5C was observed at different time after formalin injection. Results No immunohistochemical staining was found in normal rat Sp5C.After formalin injection,PLC like immunoreaction(\|LI),Fos\|LI and GFAP\|LI were found in astrocytes while PLC\|LI and Fos\|LI in neurons.The labeled astrocytes and neurons showed similar distribution and close relationship.PLC\|LI and Fos\|LI were found earlier than that in neurons.Conclusion\ The results suggested that the astrocytes in the Sp5C might participate in pain modulation in CNS and actively regulate neuron′s function.
10.Observational study about dezocine combined with dexmedetomidine for sedation and analgesia in ICU patients with mechanical centilation
Jingyi DUAN ; Zhenyu ZHANG ; Yuan XU
The Journal of Clinical Anesthesiology 2017;33(8):765-767
Objective To evaluate the effects on mechanical ventilation in ICU patients with dexmedetomidine merely and combined with dezocine, fentanyl, respectively.Methods Fifty-seven patients with mechanical ventilation in ICU were collected during Jun till Dec in 2016, 35 males and 22 females, aged 18-75 years, and classified into three groups with random number table method, among whom there were 17 patients treated with dexmedetomidine, 20 patients treated with dexmedetomidine combined with dezocine and 20 with dexmedetomidine plus fentanyl, the general condition, pain score, MAP and HR were compared before and after the treatment, ideal treatment time and mechanical ventilation time were also compared among the different groups.Results There were no statistical differences in the general condition, CPOT score, MAP and HR at different points and mechanical ventilation time.Whereas, the time of ideal sedation and analgesia was significantly faster in group C than that of groups A and B (P<0.05).Conclusion Dexmedetomidine combined with dezocine can reach the ideal analgesic effect more rapidly than dexmedetomidine solely or combined with fentanyl.