1.Diffusion spectrum magnetic resonance imaging
Lin TIAN ; Hao YAN ; Dai ZHANG
Journal of Peking University(Health Sciences) 2009;41(6):716-720
SUMMARY Diffusion spectrum imaging ( DSI) , a newly developed MRI technique, affords the capacity to map complex fiber architectures in tissues with sufficient angular resolution by imaging the spectra of tissue water diffusion. By contrast, diffusion tensor imaging (DTI) , the currently widely used technique based on the 2nd order tensor model, obtains an approximation of the complex diffusion, and provides only one global maximal direction corresponding to the primary eigenvector for each voxel. As a generalized model-free diffusion imaging technique, firstly, DSI employs the probability density function to describe the diffusion process in each voxel; secondly, a sufficient dense signal sample derived from repeated applications of diffusion-weighed gradients ensures its capability to resolve the diffusion probability density function; thirdly, specific computer visualization techniques are used to extract the diffusion information and reconstruct the geometrical properties of tissue microstructure. The capacity to unravel complex tissue architecture, recent improvements in hardware and ongoing optimization of sequence design and algorithm enable a rapid growth of DSI for research use and future incorporation into clinical protocols. This paper introduces the basic principles of DSI and then compares the characteristics of DSI and DTI schemes. Finally, the typical applications of DSI to date are reviewed.
2.Optimization of Saccharomyces cerevisiae sp.Strain by1.1b Culture Conditions for Efficient Biosynthesis of D-(-)-mandelate Dehydrogenase
Fen YAN ; Qian WANG ; Zi-Lin LIN ; Yang-Hao GUO ;
Microbiology 1992;0(01):-
The culture conditions of Saccharomyces cerevisiae sp.strain by 1.1 b were optimized for the production of D-(-)-mandelate dehydrogenase which is useful for the asymmetric bioreduction of benzoylformate to form D-(-)-mandelate.The optimum medium(per liter)consistes of 60 g peptone,30 g maltose, 0.5 g MgSO_4,0.01 g ZnSO_4,1.0 g KCl.After optimization of the culture medium,the enzyme production in shake flasks is enhanced from 2.56 to 20.21 U/L.The optimum fermentation conditions were determined as follows:medium volume 100 mL(i.e.,40%for a 250-mL shake flask),pH 6.5,inoculum size 10%,temperature 30℃,and cultivation time 25 h.
3.Effect of overexpressing isocitrate lyase on succinate production in ldh(-1) Corynebacterium glutamicum.
Chao YANG ; Ning HAO ; Ming YAN ; Lu GAO ; Lin XU
Chinese Journal of Biotechnology 2013;29(11):1696-1700
Corynebacterium glutamicum SA001 is a mutant with lactate dehydrogenase (ldhA) deletion. In order to increase metabolic flux from isocitrate to succinate, and to improve the production of succinate under anaerobic conditions,we transducted the gene aceA coding isocitrate lyase (ICL) from Escherichia coli K12 into Corynebacterium glutamicum SA001 (SA001/pXMJ19-aceA). After 12 h aerobic induction by adding 0.8 mmol/L of IPTG, the recombinant strain was transferred to anaerobic fermentation for 16 h. Succinate reached 14.84 g/L, with a productivity of 0.83 g/(L x h). Compared to C. glutamicum SA001, the activity of ICL of the recombinant strain was increased 5.8-fold, and the succinate productivity was increased 48%. Overexpression of isocitrate lyase will increase the metabolic flux of glyoxylate bypass flowing to succinate.
Corynebacterium glutamicum
;
genetics
;
metabolism
;
Escherichia coli
;
enzymology
;
genetics
;
Gene Deletion
;
Industrial Microbiology
;
Isocitrate Lyase
;
biosynthesis
;
genetics
;
L-Lactate Dehydrogenase
;
genetics
;
Succinic Acid
;
metabolism
;
Transduction, Genetic
5.Related investigation and thinking on the course of Laboratory diagnostics in general medical train-ing from the Navy physicians
Zaixing YANG ; Lin ZHOU ; Hao WANG ; Xiaoxia FAN ; Yan LIANG
Chinese Journal of Medical Education Research 2016;15(11):1185-1188
Objective To investigate and analyze the application and effect of the course of Labo-ratory diagnostics in general medical training from the Navy physicians. Methods 37 students attending the general medical training in our university in September 2015 were selected as the subject. At the end of the course, the “Questionnaire Survey on Teaching Feedback” was designed and conducted among them to understand the students'!opinions on the arrangement, teaching content and teaching methods of the experi-mental diagnostics. A total of 37 questionnaires were issued and retrieved effectively and the survey data were collected and summarized. Results Among 37 questionnaires, 100%of trainees (n=37) thought it was necessary to set up the Laboratory diagnostics course in the general medical training, 72.9%(n=27) suggested 3 to 4 teaching hours, and on the demand side of teaching content settings, 91.9%(n=34) chose analyses of blood, urine, stool routine tests and then tests of liver and kidney function. The proportions of students to recommend theory teaching, case discussion and practice operation were 24.3% (n=9), 51.4% (n=19) and 48.6% (n=18) respectively. Conclusions The setup of the Laboratory diagnostics course plays an active role in the general medical training from navy physicians. In the future, according to the demand of the general medical training, teachers should optimize the teaching contents and learning hours, improve the teaching methods and enhance the training quality.
6.The relationship between serum C-reactive protein levels in type 2 diabetic patients and periodontal diseases
Tao HAO ; Lin GAO ; Yan YANG ; Xin LIAO
Journal of Practical Stomatology 2001;0(03):-
Objective:To investigate serum high sensitive C-reactive protein levels in type 2 diabetic patients with periodontal diseases,and to explore the relationship between serum high sensitive C-reactive protein levels and periodontal diseases in type 2 diabetic patients.Methods:The study included 20 type 2 diabetic patients with moderate or severe periodontal diseases,20 type 2 diabetic patients without periodontal diseases and 20 normal as control.Serum hs-CRP,HbA1c and other biochemical parameters were detected.Results:Compared with normal control and type 2 diabetic subjects without periodontal diseases,serum hs-CRP levels in type 2 diabetic patients with moderate or severe periodontal diseases were significantly increased.Serum hs-CRP levels were significantly elevated in type 2 diabetic patients without periodontal diseases compared with normal control subjects(P
7.Change of Cytokines in Mice with Echinococcus multilocularis Infection
Xiaoli WEI ; Jianbing DING ; Yan XU ; Hao WEN ; Renyong LIN
Chinese Journal of Parasitology and Parasitic Diseases 1997;0(06):-
Objective To observe the change of six cytokines in mice infected with Echinococcus multilocularis as part of the study on immunological mechanism in the infection. Methods Mice were infected by abdominal inoculation of echinococcus protoscoleces. The change of serum level of the cytokines IL-2、IFN-?、TNF-?、IL-4、 IL-5 and IL-10 was determined by ELISA during the infection which lasted for 260 d. Results Compared with uninfected control, the levels of the cytokines all significantly increased in the 260 d. The level of IL-2 reached a peak after 80 d post-infection (p.i.), then decreased quickly after 140 d p.i., High level of TNF-? was detected after 40 d, compared to uninfected control, reached a peak at 100 d p.i., and decreased quickly after 140 d. The level of IFN-? reached a peak after 80 d p.i., and decreased slowly after 140 d p.i., The levels of IL-4, IL-5 and IL-10 remained lower before 80 d, and increased sharply after 100 days. The levels of IL-4 and IL-10 reached peaks at 100 d p.i., and that of IL-5 at 140 d p.i. Conclusion The data suggest that the induction of Th2 antibody-mediated immunity (AMI) with a parallel expansion of Th1 cell-mediated inflammatory (CMI) responses are important mechanism of the host in defending against the metacestodes. Th1 CMI plays an important role at the early stage of infection, and Th2 AMI is important in the later stage of infection.
8.Analysis effects of shuxuening injection on patient's liver function based on electronic medical data.
Teng-Teng HAO ; Yan-Ming XIE ; Wei YANG ; Yong-Yan WANG ; Lin LI ; Yan ZHUANG
China Journal of Chinese Materia Medica 2014;39(18):3609-3615
To assess whether the Shuxuening injection influences liver function, this paper analyzes the hospital information system (HIS) data from 20 national hospitals. The patients were divided two groups: patients (5 353 cases) using Shuxuening injection acted as the exposed group, then the patients (4 863 cases) not using Shuxuening injection acted as the unexposed group. Take the abnormal changes of alanine aminotransferase and aspartate aminotransferase indexes as the result. Control confounding factors by stratification analysis, classic logistic regression analysis, before logistic regression based on propensity score weighting method and logistic regression based on generalized boosted models (GBM) of propensity score weighted combination of covariate adjustment. Then, the study analyzes the effects of Shuxuening injection on liver function by observing the changes of the indexes. Analysis of the impact of parenterally administered Shuxuening on ALT shows that, before logistic regression based on propensity score, then the regression is -0.232 (P value is 0.017). However, after logistic regression based on propensity score method the regression became -0.150 (P value is 0.370). Whereas, analysis of the impact of parenterally administered Shuxuening on AST shows that, before logistic regression based on propensity score, then the regression is -0.034 (P value is 0.767). However, after logistic regression based on propensity score method the regression became -0.091(P value is 0.538). Thus, propensity score method can control a large number of confounding factors, making the results more close to the clinic. Hence, based on existing electronic medical data, this study didn't find that parenterally administered Shuexuening influences ALT and AST.
Adolescent
;
Adult
;
Aged
;
Aged, 80 and over
;
Drugs, Chinese Herbal
;
administration & dosage
;
adverse effects
;
Electronic Health Records
;
Female
;
Humans
;
Injections
;
Liver
;
drug effects
;
metabolism
;
Logistic Models
;
Male
;
Middle Aged
;
Young Adult
9.Characteristics of long-term survivors on peritoneal dialysis
Aiwu LIN ; Jiaqi QIAN ; Wei FANG ; Zhaohui NI ; Hao YAN ; Liou CAO ; Xinghui LIN
Chinese Journal of Nephrology 2008;24(12):868-871
ObjectiveTo evaluate the characteristics of patients on long-term peritoneal dialysis (PD). MethodsPatients who started PD since 1994 and received PD for at least one year were included in this study. According to dialysis duration, patients were divided into two groups. Group A (long-term) was defined as patients survived on PD for more than 5 years. Group B (short-term) was defined as patients who died or switched to bemodialysis within less than 5 years. Demography, biochemical indexes, dialysis prescription and adequacy were compared between two groups. ResultsThere were 68 patients in group A and 98 patients in group B. Mean followed-up period of group A and B was (84.80±19.42) months and (27.25±12.31) months, respectively. Younger, fewer episodes of diabetic comorbidity (group A 3/68 vs group B 18/98, P <0.05) and coronary heart disease (group A 6/68 vs group B 22/98, P<0.05) were found in group A. Compared to group B, the level of serum albumin at the beginning of PD was much higher in group A [(35.56±4.74) g/L vs (33.69±5.45) g/L, P<0.01). The levels of blood sugar, TC, TG, hemoglobin, calcium, phosphate and iPTH were not significantly different between two groups. Estimated GFR, renal Kt/V and renal Ccr at the beginning of dialysis were much higher in group A, however there was no significant difference in urinary volume between two groups. Both estimated GFR and urinary volume decreased more slowly in group A compared to group B. Peritonitis mobidity was lower in group A (1/81.22 months vs 1/29.03 months, P<0.01). Conclusions In comparison to short-term survivors, long-term PD patients are characterized by being younger, less diabetic and coronary heart disease, fewer episodes of peritonitis, higher level of serum albumin, higher estimated GFR and less loss of residual renal function.
10.Efficacy of 308-nm excimer light in the treatment of stable vitiligo
Rui YIN ; Jun DENG ; Xichuan YANG ; Cunjian ZHOU ; Fei HAO ; Lin LIN ; Yan XIAO
Chinese Journal of Dermatology 2011;44(8):594-595
Objective To evaluate the efficacy and safety of 308-nm excimer light in the treatment of stable vitiligo. Methods Thirty patients with stable vitiligo were enrolled in this clinical trial. All the subjects received the treatment with 308-nm excimer light on a twice-weekly schedule for 3 months. Results The repigmentation rate was 95.0%, 75.0% and 66.7% for lesions in the face and neck, trunk and limbs, with the treatment sessions averaging 10.22 ± 1.60, 19.10 ± 2.38, 37.74 ± 3.06, respectively, and accumulative irradiation dose averaging 7.50 ± 3.45, 10.60 ± 1.01, 18.56 ± 3.05 J/cm2 respectively. Significant differences were observed in the repigmentation rate and treatment sessions between the lesions in the face and neck, trunk and limbs (all P < 0.05). No severe side effects were seen during the treatment. Conclusion 308-nm excimer light is effective and safe for the treatment of vitiligo.