1.Determination of somatostatin in serum by large pore liquid chromatography column
Parenteral & Enteral Nutrition 2004;0(05):-
Objective: To develop a method in the determination of somatostatin level in blood for clinical medication. Methods: A method for the determination of somatostatin(Octreotide) in serum by high performance liquid chromatography with diode-array detector(DAD) was developed.After ultrafiltration,the pH values of blood samples were adjusted to 4,and samples were analyzed by Kromasil C18 column(4.6 mm? 250 mm,5 ?m i.d.) with a large pore(300) by acetonitrile/water/trifluoroacetic acid(20/80/0.01%,v/v) as mobile phase. Results:The recovery rate of Octreotide was 85%,and the calibration curve showed good linearity in the range of 0.006-0.5 mg/mL. Conclusion: The method is suitable for the detection of Octreotide content by liquid chromatography.
2.Establishment of the method for determination of serum citrulline and its application in intestinal transplantation
Fangnan LIU ; Li TAN ; Nan LUO
Chinese Journal of Organ Transplantation 2005;0(07):-
Objective To investigate the level of serum citrulline and its significance in the patients subject to intestinal transplantation. Methods Phenylisothiocyanate served as derivative reagent and the serum citrulline was determined by HPLC. Thirty-three healthy adults served as controls. Serum citrulline was measured in 2 cases of intestinal transplantation during different transplant periods. Results The serum citrulline level in 33 healthy adults was (16.87?5.97)?mol/L. Before operation, it was low (less than 10 ?mol/L) in the patients and after operation it reached to high levels and kept at higher levels. The maximium of serum citrulline was more than 30 ?mol/L in patient A and was over 50 ?mol/L in patient B. Following rejection, the serum citrulline level in patient A was decreased rapidly and simialr to that before operation and in patient B it was lower than that before operation. Conclusion The level of serum citrulline in intestinal transplantation patients was correlated with transplant rejection. More patients are reqiured for the further study.
3.The measurement of vitamine B in the patients with Crohn's disease by HPLC
Fangnan LIU ; Xiuzhen WAN ; Qingsong TAO
Parenteral & Enteral Nutrition 1997;0(03):-
Objective: To compare the difference of Vitamin B in serum in healthy adults and patiens with Crohn's disease.Methods: 24 healthy adults and 20 patients were measured for Vitamin B1,B6,B12 in serum.A HPLC-DAD method was developed to determine vitamin B extracted directly from human serum.Purospher RP-18 column was used for the gradient elution with mobile phase: 0.04 mol phosphate buffer: methanol(60∶40).Results: The results proved to be linear in measurements of VB1,VB6 and VB12 and the correlation coefficients were 0.999 827,0.985 097 and 0.999 994,respectively.The contents of Vitamin B(VB1,VB6,VB12) in Cronhn's patients were significantly lower than in healthy adults.Conclusion: The measurements of Vitamin B in human serum by HPLC-DAD method are clinically helpful to diagnosis and treatment for Crohn's disease.
4.Simultaneous determination of lactulose and mannitol excretion ratio in urine by high performance liquid chromatography
Fangnan LIU ; Li TAN ; Nan LUO ;
Parenteral & Enteral Nutrition 1997;0(04):-
Objective: Lactulose and mannitol excretion ratio in urine appears to be a marker to measure the intestinal permeability. Methods: A method has been developed for the simultaneous determination of lactulose and mannitol in urine by high performance liquid chromatography.After ultrafiltered and deionized,urine samples were analyzed with a lichrosher NH 2 column(4.6 mm?250 mm,i.d.,5 ?m),a mix of acetonitril water (72∶28,volume ratio) as mobile phase and refractive index detector. Results: The recoveries were 97.86%、 99.19% respectively and the relative standard deviation were 2.12、2.04.In 18 urine samples from healthy volunteers and patients who ingested the test solution containing 10 g lactulose and 5 g mannitol,the 6 h urinary excretion ratio of lactulose/mannitol was 0.0275?0.0113. Conclusions: It is suggested that lactulose and mannitol excretion ratio was anaccurate marker of intestinal permeability.
5.Determination of 3-methylhistidine and tyrosine in incubated buffer and checking samples by HPLC with PITC pre-column derivation
Fangnan LIU ; Li TAN ; Nan LUO ; Wei ZHOU
Parenteral & Enteral Nutrition 1997;0(03):-
Objectives:To determine 3-methylhistidine(3-MH) and tyrosine(Tyr) in standard solution and preparations by high performance liquid chromatography(HPLC) with phenylisothicyanate(PITC) pre-column derivation. Methods:PITC was used as pre-column derivative of HPLC and stored in refrigerator after drying.Two phases gradient elution was performed with acetic sodium and cyanide for 50 minites. Results:The linearity of the measurement was very good for 3-MH and Tyr(r= 0.999 1 and 0.999 2).The recovery rate was 82.6% and 87.6%,respectively. Conclusions:The method of HPLC with PITC pre-column derivation for determination of 3-MH and Tyr is stable,efficient,and sensitive.PITC is an ideal derivative.
6.Metabolic effects of administration of branched chain amino acids on postoperative patients
Jun GU ; Ning LI ; Guohao WU ; Min XIE ; Fangnan LIU ;
Parenteral & Enteral Nutrition 1997;0(02):-
Objective: To investigate the metabolic effects of two different formula of amino acids on postoperative patients . Methods: According to prospective ,randomized , single blind and controlled rule, 120 patients after abdominal operation were randomized to receive parenteral nutrition with either amino acid enriched BCAA or balanced amino acid (18 F).From the second day after operation, total parenteral nutrition was infused to the patients with equal calorie and equal nitrogen by central or peripheral vein for 6 days. Meanwhile, every day nitrogen balance was monitored by collecting urine in 24 hours .The indices were investigated such as amino acids patterns, and serum levels of total protein, albumin, prealbumin, thansferrin and fibronectin. Results: Nitrogen balance of patients in study group on day5 was higher than those of control group. The decreased serum levels of albumin in study group were lower than the control group. Concentrations of valine increased more significantly in study group than that of the control group. Conclusions: The formula of amino acid enriched BCAA may be more suitable and effective for the postoperative traumatic patients on protein metabolism.
7.Functions of retinoic acid on the biological characteristics of human embryonic stem cells.
Xin FU ; Wenbo LIU ; Fangnan XIE ; Ran XIAO
Chinese Journal of Plastic Surgery 2014;30(3):191-196
OBJECTIVETo analyze the influence of retinoic acid (RA) on the undifferentiated state and EB formation abilities of human embryonic stem cells.
METHODSThe biological characteristics of H9 ESCs after RA treatment were characterized by real-time PCR, MTS proliferation assay and immunofluorescence staining. The expression of three germ layers markers, osteogenic differentiation markers and adipogenic differentiation markers in H9-differentiated embryoid bodies (EBs) with RA treatment were quantified by real time PCR.
RESULTSThe proliferation of H9 ESCs in the early logarithmic growth phase was accelerated by RA treatment. In addition, RA induced differentiation of H9 ESC coupled with morphology changes, decreased expression of undifferentiated markers Oct4, Nanog, Sox2 and OCT4 mRNA binding protein Lin28 at mRNA level, and reduced expression of Oct4 at protein level. RA induced formation of cavities in EBs. Real time PCR results showed that the expressions of ectodermal markers: NeuroD1, Noggin; mesodermal markers: Brachyury, Twist and endodermal markers: AFP, GATA-4 were significantly increased (P < 0.05), especially for AFP (P < 0.01), by RA treatment in a dose-dependent manner. In addition, the expression of adipogenic differentiation marker C/EBPalpha was increased while the osteogenic differentiation marker OPN was decreased in EBs after RA treatment for 5 days.
CONCLUSIONSHigh concentrations of RA induced the loss of stemness in H9 ESCs and excessive differentiation in EBs, and damaged the balance between osteogenic and adipogenic differentiation during early EB differentiation, which may be relevant to the congenital malformations.
Cell Differentiation ; drug effects ; Cell Proliferation ; drug effects ; Cells, Cultured ; Embryonic Stem Cells ; cytology ; drug effects ; Humans ; Tretinoin ; pharmacology
8.An experimental study of metabolic intervention of anti-TNF antibody in intra-abdominal infection complicated by multiple organ dysfunction syndrome
Zhufu QUAN ; Fangnan LIU ; Yongming CHEN ; Jing ZANG ; Jieshou LI ;
Parenteral & Enteral Nutrition 1997;0(02):-
Objectives:To observe the effect of metabolic intervention of anti TNF antibody on the hypermetabolism occurred in intra abdominal infection(IAI) complicated by multiple organ dysfunction syndrome(MODS). Methods:Twenty rabbits were operated on with cecal ligation plus puncture(CLP) inducing IAI and MODS and were randomly divided into two groups, one receiving the anti TNF serum raised against TNF ?(anti TNF group) at 0.5?h after CLP and another receiving the non specific serum (control group). All animals were placed in metabolic cages and maintained with intravenous infusion for the observation period of one week. Serum levels of cytokines(TNF, IL 6), hormones (cortisol, insulin, glucagon), biochemical indexes (glucose, cholesterol, triglyceride, albumin) and daily excretions of urea nitrogen (UN),creatinine (Cr) and 3 methylhistidine (3 MH) were dynamically determined for 7 days. The death of animals was also recorded. Results:Compared with the control group, the levels of serum TNF, IL 6 and cortisol were significantly decreased and the levels of insulin and glucagon were kept normal after the injection of immune serum in anti TNF group, with significant improvements of biochemical indexes and decreased excretions of UN, Cr and 3 MH in urine. The survival rate was significantly increased in the anti TNF group. Conclusions:The anti TNF antibody can attenuate the metabolic abnormalities of IAI and MODS, being of the metabolic intervention on the hypermetabolism.
9.The effect of lipopoly-saccharide on glutamine metabolism in the rat Kupffer cells
Xin SHI ; Jieshou LI ; Fangnan LIU ; Yongming CHEN ;
Parenteral & Enteral Nutrition 1997;0(03):-
Objectives:To observe the metabolism of glutamine in the rat Kupffer cells and the effect of endotoxin. Methods:The changes of glutamine concentrations were measured before and 24 h after the in vitro cultures of the rat Kupffer cells with or without the stimulations of lipopoly saccharide. Results:Consumption and utilization rate of Gln in Kupffer cells with no LPS were (225?24)?mol/L and (9 33?0 99)% repectively.When the concention of LPS was 10.00 mg/L,consumptoin and utilization of Gln were (4 937?289)?mol/L and (73.29? 4.72 )%. Conclusions:Glutamine is an important substrate of Kupffer cell metabolism in the rest and LPS activated conditions.
10.Measurement of intestinal permeability in normal Chinese volunteers
Xiaohua JIANG ; Ning LI ; Fangnan LIU ; Yuanxin LI ; Jieshou LI ;
Parenteral & Enteral Nutrition 1997;0(04):-
Objectives:To establish a confident and sensible method of measuring lactulose(L) and mannitol(M) in human urine, and to research lactulose and mannitol excretion ratio of urine in normal Chinese volunteers in 6 hours after taking lactulose and mannitol. Methods:20 healthy volunteers took 10g of lactulose and 5g of mannitol, and 6 hours of urine was collected. The L and M concentration was analyzed by HPLC RI. The excretion of L and M and the L/M ratio was calculated. Results:The excretion of L and M in the urine was 5.74%?0.58% (0.65 %~11.47%) and 0.132%?0.012%( 0.005 %~0.206%),while the L/M ratio was 0.028? 0.010 (0.013~0.051). Conclusions: HPLC is a kind of confident and sensible method to analyze L and M concentration. The L/M ratio can reflect the intestinal mucosal permeability and can be used to monitor intestinal barrier function in clinical practice.