HPLC法同时测定复方阿胶补血颗粒中4种氨基酸

目的 建立高效液相色谱(HPLC)法同时测定复方阿胶补血颗粒中4种氨基酸。方法 采用Waters Sunfire C₁₈色谱柱（4.6 mm × 250 mm,5 mm）,以乙腈-0.1 mol·L^-1醋酸钠溶液（用36%乙酸调节pH值至6.5）（7∶93）为流动相A,以乙腈-水（4∶1）为流动相B,梯度洗脱（0~13 min,100% A ® 93% A;13~17.9 min,93% A ® 88% A;17.9~29 min,88% A ® 85% A;29~39 min,85% A ® 66% A;39~45 min,66% A ® 0% A）,柱温43 °C,体积流量1.0 mL·min^-1,检测波长254 nm。结果 L-羟脯氨酸、甘氨酸、丙氨酸、L-脯氨酸进样量分别在0.012 ~ 0.117、0.022 ~ 0.218、0.010 ~ 0.097、0.016 ~ 0.160 mg范围内与色谱峰峰面积呈良好的线性关系;平均回收率（n=6）分别为96.4%、97.3%、97.1%、99.4%;RSD分别为1.2%、1.9%、1.7%、0.9%。结论 该方法操作简单,重复性好,为控制复方阿胶补血颗粒的质量提供了可靠的方法。     

甘氨酸龈下喷砂联合引导组织再生术治疗种植体周围炎

目的探讨甘氨酸龈下喷砂联合引导组织再生术（GTR）治疗种植体周围炎的有效性。 方法28例伴有牙槽骨吸收的种植体周围炎患者,按照随机、双盲、对照原则将种植体（共34枚）分成2组,分别行GTR,其中试验组（n= 18）在术中使用甘氨酸龈下喷砂系统对种植体表面进行清创;对照组（n= 16）采用塑料刮治器对种植体表面进行清创。在治疗前（基线）、治疗后3个月、治疗后6个月和治疗后12个月进行临床指标的检测,包括菌斑指数（PLI）、出血指数（BI）、探诊深度（PD）、临床附着水平（CAL）及影像学垂直骨增量。数据采用重复测量资料的方差分析,每个时间点采用独立样本t检验进行分析,试验组和对照组分别进行治疗前与治疗后的自身对比,并在基线、治疗后3个月、治疗后6个月和治疗后12个月进行临床指标的组间对比,以P<0.05为差异有统计学意义。 结果在基线,试验组和对照组各临床指标差异无统计学意义（P>0.05）。各组术后PLI、BI、PD、CAL及影像学垂直骨增量均较治疗前（基线）有明显改善,差异有统计学意义（P<0.05）。患者治疗后3个月,试验组与对照组BI、PLI、PD、CAL差异均有统计学意义（t_BI= 5.103,P_BI= 0.031;t_PLI= 5.556,P_PLI= 0.025;t_PD= 4.440,P_PD= 0.043;t_CAL= 4.879,P_CAL= 0.034）。患者治疗后6个月,试验组和对照组的PD、CAL差异均有统计学意义（t_PD= 4.994,P_PD= 0.033;t_CAL= 4.831,P_CAL= 0.035）。患者治疗后12个月,试验组和对照组的PD、CAL差异均有统计学意义（t_PD= 4.302,P_PD= 0.046;t_CAL= 4.325,P_CAL= 0.048）。患者治疗后6及12个月,试验组与对照组种植体的PLI和BI均有改善,但差异无统计学意义（P>0.05）。患者影像学垂直骨增量在治疗后3、6、12个月试验组较对照组增加更明显,差异均有统计学意义（t₃=4.831,P₃= 0.035;t₆= 4.412,P₆= 0.044;t₁₂= 5.087,P₁₂= 0.031）。 结论在改善种植体周围炎炎症水平及促进牙槽骨再生方面,甘氨酸龈下喷砂联合GTR较机械刮治联合GTR更具优势,可考虑在GTR中使用甘氨酸龈下喷砂来提高种植体周围炎的治疗效果。     

Efficacy and safety of a soy isoflavone extract in postmenopausal women: a randomized, double-blind, and placebo-controlled study

OBJECTIVE: To investigate the efficacy of soy isoflavone on climacteric symptoms in postmenopausal women. DESIGN: In this double-blind, randomized, placebo-controlled study, a total of 80 women (mean age = 55.1 years), who reported 5 or more hot flush episodes per day, were randomized to receive either 250 mg of standardized soy extract (Glycine max AT) a total of 100mg/day of isoflavone (n = 40) or placebo (n = 40). Exclusion criteria included: contra-indication for hormone therapy (HT), chronic gastrointestinal diseases, and users of HT within the preceding 6-months. For 10-months, climacteric symptoms were evaluated using a score card and the menopausal Kupperman index. Compliance and safety were also assessed. At baseline and the end of the study, lipid and hormonal profiles, as well as vaginal, mammographic and ultrasonographic parameters were measured. The t-test, Wilcoxon test and ANOVA were used in the statistical analysis. RESULTS: At baseline, the mean number of hot flushes was 9.6 +/- 3.9 per day in the isoflavone group and 10.1+/-4.9 in the placebo group (p>0.05). After 10 months, there was a significant reduction in frequency of hot flushes among isoflavone users when compared to those on placebo (3.1 +/- 2.3 and 5.9 +/- 4.3, respectively) (p<0.001). Kupperman index mean values showed a significant reduction in both groups. However, soy isoflavone was significantly superior to placebo, in reducing hot flush severity (69.9% and 33.7%, respectively) (p<0.001). Endometrial thickness, mammography, vaginal cytology, lipids and hormonal profile did not change in both groups. No serious adverse event related to isoflavone treatment was reported. CONCLUSIONS: The soy isoflavone extract exerted favorable effects on vasomotor symptoms and good compliance, providing a safe and effective alternative therapeutic for postmenopausal women.     

Amino acid signatures in the developing mouse retina

This study characterizes the developmental patterns of seven key amino acids: glutamate, γ-amino-butyric acid (GABA), glycine, glutamine, aspartate, alanine and taurine in the mouse retina. We analyze amino acids in specific bipolar, amacrine and ganglion cell sub-populations (i.e. GABAergic vs. glycinergic amacrine cells) and anatomically distinct regions of photoreceptors and Müller cells (i.e. cell bodies vs. endfeet) by extracting data from previously described pattern recognition analysis. Pattern recognition statistically classifies all cells in the retina based on their neurochemical profile and surpasses the previous limitations of anatomical and morphological identification of cells in the immature retina. We found that the GABA and glycine cellular content reached adult-like levels in most neurons before glutamate. The metabolic amino acids glutamine, aspartate and alanine also reached maturity in most retinal cells before eye opening. When the overall amino acid profiles were considered for each cell group, ganglion cells and GABAergic amacrine cells matured first, followed by glycinergic amacrine cells and finally bipolar cells. Photoreceptor cell bodies reached adult-like amino acid profiles at P7 whilst Müller cells acquired typical amino acid profiles in their cell bodies at P7 and in their endfeet by P14. We further compared the amino acid profiles of the C57Bl/6J mouse with the transgenic X-inactivation mouse carrying the lacZ gene on the X chromosome and validated this animal model for the study of normal retinal development. This study provides valuable insight into normal retinal neurochemical maturation and metabolism and benchmark amino acid values for comparison with retinal disease, particularly those which occur during development.     

Oxalate Metabolism after Intestinal Bypass Operations

Hyperoxaluria and kidney stones are frequent following intestinal bypass operations. The urinary oxalate excretion was studied for 10-13 days during enteral and parenteral nutrition in six patients operated on because of massive obesity with a jejunoileostomy. The oxalate excretion in urine was higher than normal in all patients on normal diet. The excretion decreased on low-oxalate diet. Further decrease was observed during total parenteral nutrition (TPN). The oxalate excretion was stabilized at a low level within 48 h after the start of TPN and was unchanged during the rest of the study. This included a period of 2 days when a load of the oxalate precursor glycine (10 and 20 g) was given parenterally to five patients, resulting in increased serum glycine concentration. A slight decrease in oxalate excretion was found when the amino acid part (Vamin® with 10% glucose) of the TPN solution was given enterally instead of parenterally in two patients. This study has indicated that the main reason for hyperoxaluria in patients with intestinal bypass operations is hyper-absorption of dietary oxalate. It seems likely that these patients have a normal endogenous oxalate production.     

d-cycloserine lowers kynurenic acid formation—New mechanism of action

d-Cycloserine, known as a partial agonist at the glycine modulatory site of the glutamatergic N-methyl-d-aspartate (NMDA) receptor, exerts anticonvulsive activities and improves cognitive function. The present study evaluates the action of d-cycloserine with respect to the biosynthetic machinery of kynurenic acid (KYNA) synthesis e.g. the activity of enzymes synthesizing KYNA, kynurenine aminotransferases I, kynurenine aminotransferase II and kynurenine aminotransferase III (KAT I, KAT II and KAT III) in the rat liver and brain, and human frontal cortex in the presence of the anti-mycobacterial drug d-cycloserine, in an in vitro study. We found that d-cycloserine blocked dose-dependent and significantly KAT I, II and III activities in rat liver and brain homogenates. Furthermore, the inhibitory effect of KYNA formation was observed in the frontal cortex homogenate of human post mortem tissue, as well. d-Cycloserine, at 63.7 µM concentration blocked significantly KAT II, I and III (53.2, 66.1 and 71.3% of control, P<0.001) activities in the human frontal cortex homogenate. Obtained data indicate that d-cycloserine exerts notable biochemical properties to block KYNA synthesis. Lowering of KYNA content due to d-cycloserine inhibition of KATs activities can free up more glycine sites for the actions of d-cycloserine. On the other site, it needs to be clarified, if the postulated mechanism for d-cycloserine to act as a partial agonist at the glycine site of the NMDA receptor could be mainly due to KAT's inhibition. We propose that this mechanism(s) might play a role in the improvement of memory, cognition and/or delusion in Alzheimer's, HIV-1 infected patients and schizophrenia patients.     

Differential distribution of activated spinal neurons containing glycine and/or GABA and expressing c-fos in acute and chronic pain models

The inhibitory transmitters GABA and glycine play an important role in modulating pain transmission, both in normal and in pathological situations. In the present study we have combined in situ hybridization for identifying spinal neurons that use the transmitter(s) glycine and/or GABA (Gly/GABA neurons) with immunohistochemistry for c-fos, a marker for neuronal activation. This procedure was used with acute pain models induced by the injection of capsaicin or formalin; and chronic pain models using Complete Freund’s Adjuvant (CFA, chronic inflammation), and the spared nerve injury (SNI) model (neuropathic pain). In all models Gly/GABA neurons were activated as indicated by their expression of c-fos. The pattern of Gly/GABA neuronal activation was different for every model, both anatomically and quantitatively. However, the averaged percentage of activated neurons that were Gly/GABA in the chronic phase (?20 h survival, 46%) was significantly higher than in the acute phase (?2 h survival, 34%). In addition, the total numbers of activated Gly/GABA neurons were similar in both phases, showing that the activation of non-Gly/GABA (presumed excitatory) neurons in the chronic phase decreased. Finally, morphine application equally decreased the total number of activated neurons and activated Gly/GABA neurons. This showed that morphine did not specifically activate Gly/GABA neurons to achieve nociceptive inhibition. The present study shows an increased activity of Gly/GABA neurons in acute and chronic models. This mechanism, together with mechanisms that antagonize the effects of GABA and glycine at the receptor level, may determine the sensitivity of our pain system during health and disease.     

Phencyclidine-induced cognitive deficits in mice are improved by subsequent subchronic administration of the glycine transporter-1 inhibitor NFPS and d-serine

Accumulating evidence suggests that the glycine modulatory site on the NMDA receptor could be potential therapeutic target for cognitive deficits in schizophrenia. The present study was undertaken to examine the effects of the glycine transporter-1 (GlyT-1) inhibitor, (R)-(N-[3-(4'-fluorophenyl)-3-(4'-phenylphenoxy)propyl])sarcosine (NFPS), on cognitive deficits in mice after repeated administration of the NMDA receptor antagonist phencyclidine (PCP). PCP (10 mg/kg/day for 10 days)-induced cognitive deficits were significantly improved by subsequent subchronic (2-week) administration of NFPS (1.0 and 3.0 mg/kg/day) or D-serine (600 mg/kg/day). However, PCP-induced cognitive deficits were not improved by a single administration of NFPS (3.0 mg/kg). Furthermore, Western blot analysis revealed that levels of GlyT-1 in the hippocampus, but not frontal cortex, of the PCP (10 mg/kg/day for 10 days)-treated mice were significantly higher than those of saline-treated mice. An in vivo microdialysis study revealed that repeated PCP administration significantly decreased the extracellular levels of glycine in the hippocampus, but not frontal cortex, of mice. These findings suggest that repeated PCP administration increased the density of GlyT-1 in the hippocampus of mouse brain, and that the GlyT-1 inhibitor NFPS could ameliorate cognitive deficits in mice after repeated administration of PCP.     

The response to l-carnitine and glycine therapy in isovaleric acidaemia

The profound metabolic disturbances which occur in isovaleric acidaemia are due to the intramitochondrial accumulation of isovaleryl coenzyme A (CoA) with a consequent reduction in the availability of free CoA. Secondary carnitine insufficiency is also a feature of this and other disorders of organic acid metabolism. A patient who presented at 2.5 years of age was diagnosed using capillary GC-MS as having isovaleric acidaemia. She showed the full spectrum of abnormal organic acids previously associated with the neonatal form of the disease despite her late presentation, indicating that it is inappropriate to refer to acute early and late onset forms of isovaleric acidaemia. Instead, a spectrum of disease exists, determined by environmental factors, residual enzyme activities and modifying effects of different phenotypes in different individuals. She also showed evidence of carnitine insufficiency. An oral challenge with l-carnitine resulted in the excretion of large amounts of urinary acylcarnitines which were shown by use of fast atom bombardment mass spectrometry to be primarily isovalerylcarnitine. Regular glycine supplementation caused no significant increase in urinary isovaleryglycine and had to be stopped because of side-effects after 5 days. An oral l-carnitine challenge during glycine supplementation resulted in a marked increase in isovalerylglycine excretion, again associated with the excretion of large amounts of isovalerylcarnitine. Carnitine acts by removing (detoxifying) intramitochondrial isovaleryl groups and, in the presence of glycine, it promotes the formation of isovalerylglycine. We believe l-carnitine supplementation is of value in the treatment of isovaleric acidaemia and that, in the present case, l-carnitine together with a moderate dietary restriction has proved to be the optimum form of therapy.Abbreviations CoA Coenzyme A - TMS trimethylsilyl - S.D. standard deviation - DEAE diethylaminoethyl - FAB fast atom bombardment