Objective To quantify the mRNA expression of NMDAR1 gene in the retina of eyes with acute elevation of IOP in rabbit. Methods Tweenty-six eyes of 16 rabbits were divided into three groups: Group 1: The IOP of one eye in 10 rabbits was elevated to 60 mm Hg by ante ri or chamber infusion. Group 2: The another eye of the same rabbit in group 1 was maintained the IOP to 20 mm Hg by anterior chamber infusion. Group 3: Unilat eral eyes of six rabbits were enucleated to evaluate the mRNA levels as normal control group. PCR product was identified by Southern blotting and the mRNA expression level was quantified by RT-PCR. Results The results revealed no significant difference between group 1 and group 2. Conclusion This implies that acute elevated IOP may not affect the mRNA expression level of NMDAR1 gene. (Chin J Ocul Fundus Dis, 2001,17:50-51)
ObjectiveTo understand the function of trace element and amino acids detection in early diagnosis of breast cancer, and explore the correlation between plasma amino acid and trace element changes. MethodsFifty-five patients with breast cancer and 50 normal controls were included in our study from May 2012 to June 2013. Trace elements were detected by atomic absorption spectrophotometer, and the level of amino acids was detected by Hitachi L-8900 amino acids analyzer. Then, we analyzed the correlation between the two indexes. ResultsCompared with the normal controls, breast cancer patients had a higher level of Cu and Fe (P<0.05), and a lower level of Zn (P<0.05). Seven kinds of amino acids had significant changes (P<0.05), including three kinds of increased amino acids, and four reduced. Amino acids and trace element correlation analysis showed that Mg was negatively correlated with Leu, Tyr, Lys, and His; and Ca was negatively correlated with Lys and His. ConclusionThere are many kinds of changes of plasma amino acids and trace elements in breast cancer patients. Serum trace element and amino acids detection in patients with breast cancer are helpful in the severity judgment and regimen design.
ObjectiveTo observe the ability of osteogenesis in vivo using the injected absorbable polyamine acid/calcium sulfate (PAA/CS) composites and assess their ability to repair bone defects. MethodWe selected 48 New Zealand white rabbits, and half of them were male with a weight between 2.0 and 2.5 kg. Bone defect models were made at the rabbit femoral condyle using electric drill, and the rabbits were divided into two groups. One group accepted implantation of the material at the defect, while nothing was done for the control group. After four, eight, twelve and sixteen weeks, the animals were killed. The line X-ray and hard tissue slices histological examination (HE, MASSON staining) were observed to assess the situation of degradation, absorption and bone formation of the material. ResultsFour weeks after operation, bone defect of the experimental group had no obvious callus growth on X-ray imaging. Histology showed that the material began to degrade and new immature trabecular bone grew. The bone defect of the experimental group had a small amount of callus growth on X-ray imaging after eight weeks. And histology showed that the material continued to degrade and new immature trabecular bone grew continually. There was an obvious callus growth after twelve weeks, and the bone defect area had smaller residual low-density shadow on X-ray imaging. Histology showed that most of the materials degraded and parts of woven bone grew into lamellar bone. After sixteen weeks, the composites were absorbed completely, replaced by new bone tissues, and the new bone was gradually changed from woven bone into mature plate of bone. There was no significant change in bone defect in the control group within twelve weeks, and part of bone defect hole became smaller, and partial edge repair could be detected. ConclusionsThe PAA/CS composites can be completely degraded and absorbed, with a certain activity of bone formation, expected to be used as bone repair materials.
Objective To evaluate the application of artificial lamina of multi-amino-acid copolymer (MAACP)/nano-hydroxyapatite (n-HA) in prevention of epidural adhesion and compression of scar tissue after posterior cervical laminectomy. Methods Fifteen 2-year-old male goats [weighing, (30 ± 2) kg] were randomly divided into experimental group (n=9) and control group (n=6). In the experimental group, C4 laminectomy was performed, followed by MAACP/n-HA artificial lamina implantations; in the control group, only C4 laminectomy was performed. At 4, 12, and 24 weeks after operation, 2, 2, and 5 goats in the experimental group and 2, 2, and 2 goats in the control group were selected for observation of wound infection, artificial laminar fragmentation and displacement, and its shape; Rydell’s degree of adhesion criteria was used to evaluate the adhesion degree between 2 groups. X-ray and CT images were observed; at 24 weeks after operation, CT scan was used to measure the spinal canal area and the sagittal diameter of C3, C4, and C5 vertebrea, 2 normal goats served as normal group; and MRI was used to assess adhesion and compression of scar tissue on the dura and the nerve root. Then goats were sacrificed and histological observation was carried out. Results After operation, the wound healed well; no toxicity or elimination reaction was observed. According to Rydell’s degree of adhesion criteria, adhesion in the experimental group was significantly slighter than that in the control group (Z= — 2.52, P=0.00). X-ray and CT scan showed that no dislocation of artificial lamina occurred, new cervical bone formed in the defect, and bony spinal canal was rebuilt in the experimental group. Defects of C4 vertebral plate and spinous process were observed in the control group. At 24 weeks, the spinal canal area and sagittal diameter of C4 in the experimental group and normal group were significantly larger than those in the control group (P lt; 0.05), but no significant difference was found between experimental group and normal group (P gt; 0.05). MRI showed cerebrospinal fluid signal was unobstructed and no soft tissue projected into the spinal canal in the experimental group; scar tissue projected into the spinal canal and the dura were compressed by scar tissue in the control group. HE staining and Masson trichrome staining showed that artificial lamina had no obvious degradation with high integrity, some new bone formed at interface between the artificial material and bone in the experimental group; fibrous tissue grew into defect in the control group. Conclusion The MAACP/n-HA artificial lamina could maintaine good biomechanical properties for a long time in vivo and could effectively prevent the epidural scar from growing in the lamina defect area.
ObjectiveTo investigate the postnatal changes in urinary metabolic amino acid levels in infants with retinopathy of prematurity (ROP) and their effect on ROP, and to analyze the amino acid metabolic pathways that may be involved in the development of ROP. MethodsA retrospective cohort study. From January 2020 to December 2023, 65 premature infants with severe ROP (ROP group) who were hospitalized, born with gestational age <32 weeks in Children's Hospital Affiliated to Zhengzhou University were included in the study. Fifty premature infants with matched sex and gestational age and no ROP were selected as the control group. Urine amino acids and their derivatives were detected by gas chromatography-mass spectrometry. The two groups were compared by independent sample t test. The metabonomics of urinary amino acids was analyzed by orthogonal partial least squares discriminant analysis (OPLS-DA) model. The variable projection importance (VIP) score >1 suggested that the substance was two groups of differentially expressed amino acids. The predictive value of urinary amino acids for severe ROP was compared by using the receiver's operating characteristic (ROC) curve and the area under the curve. After t test and metabolomics analysis, the two groups of amino acids with large differences were normalized and compared by Pearson correlation analysis. The Kyoto Encyclopedia of Genes and Genomes database was used to analyze the metabolic pathways of differentially expressed amino acids involved in ROP. ResultsCompared with the control group, the concentrations of oxalic acid -2 and thiodiacetic acid-2 in urine metabolites of children in ROP group were significantly decreased, while the concentrations of 4-hydroxybutyric acid-2, 3-methylpentadienoic acid-2(1), 2-ketoglutarate-ox-2(2) and 3, 6-epoxy-dodecanedioic acid-2 were significantly increased, with statistical differences (t=0.036, 0.005, 0.038, 0.032, 0.022, 0.011; P<0.05). The results of OPLS-DA analysis showed that amino acids of urinary metabolites in ROP group and control group were distributed in the left and right regions of the scatter plot, and there was a satisfactory separation trend between the two groups (R2Ycum=0.057 4, Q2cum=0.025 7, P<0.05). As shown in the S-Plot, the amino acids biased towards two stages are glycolic acid-2, phosphoric acid-3, oxalic acid-2, thiodiacetic acid-2, 4-hydroxybutyric acid-2, 3-methylcrotonylglycine-1, 3-methylpentadienoic acid-2(1), 2-ketoglutarate-ox-2(2) and 3, 6-epoxy- dodecanedioic acid-2, respectively. Eleven differentially expressed amino acids with VIP score >1 were screened, among which the highest VIP score was oxalate-2, glycerate-3, phosphoric acid-3, 3-methylcrotonylglycine-1, uranoic acid -3 and thiodiacetic acid-2. The difference of amino acid concentration between the two groups was the highest in 4-hydroxybutyric acid-2 and thiodiacetic acid-2. The correlation between oxalic acid-2 and glycerate-3 was the highest (r=0.830, P<0.001), and most amino acids were positive correlated. ROC curve fitting analysis showed that the combined prediction of 11 differenly-expressed amino groups had the largest area under the curve (0.816), the cutoff value was 0.531, and the sensitivity and specificity were 83.1% and 70.0%, respectively. The enrichment analysis of these 11 amino acids with significant differences suggested that the main pathways involved included butyrate metabolism, glyoxylic acid and dicarboxylic acid metabolism and lipoic acid metabolism. ConclusionAbnormal amino acid metabolism of 4-hydroxybutyrate-2, 3-methylpentadienoic acid-2(1), thiodiacetic acid-2, 2-ketoglutarate-ox-2(2), 3, 6-epoxy-dodecanedioic acid-2 may have a certain effect on the occurrence of ROP.
ObjectiveTandem mass spectrometry is used to observe the changes in amino acids level in peripheral blood of patients with chronic obstructive pulmonary disease (COPD) of different severity, and explore the related factors that affect the level of amino acids in COPD patients.MethodsA collection of 99 COPD patients from the First Affiliated Hospital of Jinzhou Medical University between May 2020 and August 2020 were divided into GOLD Ⅰ/Ⅱ group, GOLD Ⅲ group and GOLD Ⅳ group according to the results of their lung function. Thirty healthy physical examination subjects during the same period were enrolled as a healthy control group. Peripheral amino acids were detected by liquid chromatography-tandem mass spectrometry (LC-MS).ResultsThe metabolism of 11 amino acids was correlated with the onset of COPD and the disorder of amino acid metabolism became more significant with the aggravation of the disease, and branched-chain amino acids (leucine, valine) had statistically significant differences in the COPD patients with different GOLD grades (P<0.05 and VIP>1). The difference between glutamate and glutamine was statistically significant only in GOLD Ⅳ stage (P<0.05 and VIP>1). The content of tyrosine and phenylalanine gradually increased with the increase of disease severity, and had significant difference in GOLD stage Ⅳ (P<0.05).ConclusionsCOPD patients with different GOLD grades have obvious amino acid metabolism disorders, including insufficient intake of essential amino acids and increased amino acids related to muscle protein catabolism. Understanding the mechanism between amino acid metabolism and COPD may provide a new direction for the diagnosis and treatment of the disease.
Heat sensitive protein medicines are increasingly exhibiting their critical importance on treatment of various diseases at present. But their popularization and application meet a great challenge because of their heat instability. In the present study, insulin was taken as a heat sensitive protein medicine and amino acid as bio-protective agent in order to investigate if these amino acids can protect the insulin from losing its bioactivity due to desiccation. The experiment was performed by using replica exchange molecular simulation (REMD) method and Gromacs software with Gromos96 (53a6) force field. The REMD results indicated that these amino acids could protect the bioactive structure of insulin during desiccation. The configurations of the protected insulin were preserved very well. Those results proved that amino acid is a kind of good bioactive protective agent for the heat sensitive protein medicines.
目的:建立高效液相色譜分離檢測腦蛋白水解物注射液各種氨基酸的測定方法。方法:氨基酸含量測定采用異硫氰酸苯酯柱前衍生化;色譜柱為C18柱(VP-DOS;150 mm×46 mm);流動相:A為0.1 mol/L醋酸鈉溶液(冰醋酸調節pH 6.5)-乙腈(93∶7),B為水-乙腈(1∶4);檢測波長:254 nm;流速:1 mL/min;柱溫:40℃。結果:16種氨基酸在32 min內完全分離,各種氨基酸之間沒有出現干擾現象,且多次重復測定結果誤差很小。結論:建立的高效液相色譜法準確性高、重現性好,可以有效地控制腦蛋白水解物注射液的質量。
ObjectiveTo evaluate the effect of poly-amino acid/nano-hydroxyapatite/calcium sulfate (PHC) Cage in lumbar interbody fusion of the goat. MethodsEighteen mature female goats (weighing 29-33 kg) were divided into 3 groups randomly: PHC Cage group (group A), titanium Cage group (group B), and ilium group (group C). A left extraperitoneal approach was used to establish the animal model of discectomy and interbody fusion with Cage or ilium. The general situation was observed for 24 weeks after operation. X-ray films were taken to measure disc space height (DSH) before operation and at 4, 12, and 24 weeks after operation. CT three dimensional reconstuction was performed at 24 weeks after operation to evaluate the interbody fusion according to modified Brantigan grading. The specimens of L3, 4 were harvested for mechanical test, histological, and scanning electron microscope (SEM) observation at 24 weeks after operation. ResultsAll goats survived to the end of experiment. DSH at 4 weeks after operation increased when compared with preoperative one in each group, and then decreased;DSH was significantly lower at 12 and 24 weeks after operation than preoperative one in group C (P<0.05). There was no significant difference in DSH among 3 groups at preoperation and 4 weeks after operation (P>0.05);at 12 and 24 weeks after operation, DSH of groups A and B was significantly higher than that of group C (P<0.05), but no significant difference was found between groups A and B (P>0.05). CT three dimensional reconstuction showed that bony fusion was obtained in all goats of groups A and C, and in 3 goats of group B;according to modified Brantigan grading, the scores of groups A and C were significantlly higher than that of group B (P<0.05), but no significant difference between groups A and C (P>0.05). The biomechanical test showed that there was no significant difference in range of motion between group A and group B (P>0.05), which were significantly lower than that of group C (P<0.05). Microscopy and SEM observations showed that the interface between the Cage and vertebral body in group A was compact without obvious gap, and most conjunctive region was filled with osseous tissue;the interface was filled with soft tissue, and the connection was slack with obvious gap in some region in group B;the interface connection was compact, most region was filled with osseous tissue in group C. ConclusionThe interbody fusion with PHC Cage is effective in goat lumbar interbody fusion model. The interface connection is compact between the Cage and the host bone followed by micro-degradation of PHC Cage, but the long-term degradation need further observation.