Mechanism of pachymic acid in the treatment of gastric cancer based on network pharmacology and experimental verification

BACKGROUND Pachymic acid(PA)is derived from Poria cocos.PA has a variety of pharmacological and inhibitory effects on various tumors.However,the mechanism of action of PA in gastric cancer(GC)remains unclear.AIM To investigate the mechanism of PA in treating GC via the combination of network pharmacology and experimental verification.METHODS The GeneCards and OMIM databases were used to derive the GC targets,while the Pharm Mapper database provided the PA targets.Utilizing the STRING database,a protein-protein interaction network was constructed and core targets were screened.The analyses of Gene Ontology,Kyoto Encyclopedia of Genes and Genomes(KEGG),and gene set enrichment analysis were conducted,and molecular docking and clinical correlation analyses were performed on the core targets.Ultimately,the network pharmacology findings were validated through in vitro cell assays,encompassing assessments of cell viability,apoptosis,cell cycle,cloning,and western blot analysis.RESULTS According to network pharmacology analysis,the core targets were screened,and the PI3K/AKT signaling pathway is likely to be the mechanism by which PA effectively treats GC,according to KEGG enrichment analysis.The experimental findings showed that PA could control PI3K/AKT signaling to prevent GC cell proliferation,induce apoptosis,and pause the cell cycle.CONCLUSION Network pharmacology demonstrated that PA could treat GC by controlling a variety of signaling pathways and acting on a variety of targets.This has also been supported by in vitro cell studies,which serve as benchmarks for further research.

Unraveling the therapeutic mechanisms of myristic acid and luteolin 7-rutinoside in oral cancer: insights from network pharmacology and molecular docking analysis

Background:The compound Luteolin-7-rutinoside(L7R)is a flavone derivative of luteolin,predominantly identified in plant species belonging to the families Asteraceae.Conversely,Myristic acid is characterized by its structure as a 14-carbon,unsaturated fatty acid.In this investigation,we endeavor to elucidate the putative mechanisms underlying the therapeutic effects of Myristic Acid and Luteolin 7-rutinoside in the context of oral cancer treatment,employing network pharmacology coupled with molecular docking methodologies.Methods:The protein targets of Myristic Acid and Luteolin 7-rutinoside were identified through a search on the Swiss Target Database.Subsequently,a compound-target network was constructed using Cytoscape 3.9.1.Targets associated with OC were retrieved from the OMIM and GeneCards databases.The overlap between compound targets and OC-related targets was determined,and the resulting shared targets were subjected to protein-protein interaction(PPI)network analysis using the STRING database.Additionally,gene ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analyses were conducted on the identified targets.Molecular docking were performed to investigate the interactions between the core target and the active compound.Results:The component target network comprises 103 nodes and 102 edges.Among the proteins in the protein-protein interaction(PPI)network,those with higher degrees are TNF,PPARG,and TP53.Analysis through Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathways indicates that the treatment of OC with Myristic Acid and Luteolin 7-rutinoside primarily involves the regulation of miRNA transcription and inflammatory response.The identified signaling pathways include Pathways in cancer,PPAR signaling pathway,EGFR signaling pathway,and TNF signaling pathway.Molecular docking studies reveal that Luteolin 7-rutinoside and Myristic acid exhibit higher affinity towards TNF,PPARG,TP53,and EGFR.Conclusion:This study reveals the potential molecular mechanism of Myristic Acid and Luteolin 7-rutinoside in the treatment of oral cancer,and provides a reference for subsequent basic research.

Adsorption of glutamic acid from aqueous solution with calcined layered double Mg-Fe-CO_3 hydroxide

Layered double Mg-Fe-CO3 hydroxide （Mg-Fe-LDH） with a mole ratio of Mg to Fe of 3 was synthesized by coprecipitation method and calcined product Mg-Fe-CLDH was obtained by heating Mg-Fe-LDH at 500 ℃ for 6 h. The as prepared Mg-Fe-LDH and calcined Mg-Fe-CLDH were used for removal of glutamic acid （Glu） from aqueous solution, respectively. Batch studies were carried out to address various experimental parameters such as contact time, pH, initial glutamic acid （Glu） concentration, co-existing anions and temperature. Glu was removed effectively （99.9%） under the optimized experimental conditions with Mg-Fe-CLDH. The adsorption kinetics follows the Ho’s pseudo second-order model. Isotherms for adsorption with Mg-Fe-CLDH at different solution temperatures were well described using the Langmuir model with a good correlation coefficient. The intraparticle diffusion model fitted the data well, which suggests that the intraparticle diffusion is not only the rate-limiting step.

Tanshinone IIa antagonizes spinal ischemia/reperfusion injury by interfering with upstream glutamic acid factors

Based on the hypothesis that upstream factor inhibition results in better treatment effects than downstream factor inhibition,the present study interfered with glutamic acid（Glu）-released upstream factors,such as Glu transporter function and Na＋-K＋-adenosine triphosphatases（ATPase）activity relativly.Rats with spinal cord ischemia/reperfusion injury received intraperitoneal injections of tanshinone Ila and Glu uptake and Na＋-K＋-ATPase activity were increased.Results showed that tanshinone Ila influenced Glu-released upstream factors following spinal ischemia/reperfusion injury and protected against spinal ischemia/reperfusion injury.

Metal ion-binding properties of L-glutamic acid and L-aspartic acid, a comparative investigation

A comparative research has been developed for acidity and stability constants of M(Glu)1, M(Asp)2 and M(Ttr)3 complexes, which have been determined by potentiometric pH titration. Depending on metal ion-binding properties, vital differences in building complex were observed. The present study indicates that in M(Ttr) com-plexes, metal ions are arranged to the carboxyl groups, but in M(Glu) and M(Asp), some metal ions are able to build chelate over amine groups. The results mentioned-above demonstrate that for some M(Glu) and M(Asp) complexes, the stability constants are also largely determined by the affinity of metal ions for amine group. This leads to a kind of selectivity of metal ions, and transfers them through building complexes accompanied with glutamate and aspartate. For heavy metal ions, this building complex helps the absorption and filtration of the blood plasma, and consequently, the excursion of heavy metal ions takes place. This is an important method in micro-dialysis. In this study the different as-pects of stabilization of metal ion complexes regarding to Irving-Williams sequence have been investigated.

Sequential elevation of autoantibodies to thyroglobulin and glutamic acid decarboxylase in type 1 diabetes

We have previously reported the high levels of glutamic acid decarboxylase 65 autoantibodies(GAD65A)in patients with type 1 diabetes and autoimmune thyroid disease.Here we describe a 32-year-old Japanese female with a thirteen-year history of type 1 diabetes whose levels of GAD65A were elevated just after the emergence of anti-thyroid autoimmunity.At 19 years of age,she developed diabetic ketoacidosis and was diagnosed with type 1 diabetes.She had GAD65A,insulinoma-associated antigen-2 autoantibodies(IA-2A),and zinc transporter-8 autoantibodies(ZnT8A),but was negative for antibodies to thyroid peroxidase(TPOAb)and thyroglobulin(TGAb)at disease onset.ZnT8A and IA-2A turned negative 2-3 years after the onset,whereas GAD65A were persistently positive at lower level(approximately 40 U/mL).However,just after the emergence of TGAb at disease duration of 12.5 years,GAD65A levels were reelevated up to5717 U/mL in the absence of ZnT8A and IA-2A.Her thyroid function was normal and TPOAb were consistently negative.She has a HLA-DRB1*03:01/*04:01-DQB1*02:01/*03:02 genotype.Persistent positivity for GAD65A might be associated with increased risk to develop anti-thyroid autoimmunity.

Granulocyte colony-stimulating factor increases extracellular glutamic acid uptake and suppresses free radicals in an experimental model of amyotrophic lateral sclerosis

Excitatory amino acid toxicity and free radical damage play important roles in amyotrophic lateral sclerosis. Granulocyte colony-stimulating factor （G-CSF） protects nerve cells exposed to high-concentrations of glutamic acid, suggesting positive effects in the treatment of amyotrophic lateral sclerosis. The present study induced in vitro motor neuron injury using glutamic acid excitotoxicity, and the biochemical effects of G-CSF on glutamic acid concentration were determined. In addition, the effects of G-CSF on superoxide dismutase, glutathione peroxidase activity in motor neurons, and malondialdehyde and nitric oxide contents were analyzed. Immunohistochemistry was performed to measure neuronal survival. Results revealed that G-CSF significantly suppressed free radical activity, inhibited excitotoxicity, and reduced apoptosis and loss of motor neurons in the anterior horn of the spinal cord.

Analysis of Glutamic Acid in Cerebrospinal Fluid by Capillary Electrophoresis with High Frequency Conductivity Detection

A rapid method to determine glutamic acid (Glu) in cerebrospinal fluid (CSF) by capillaryelectrophoresis with high frequency conductivity detection (contactless conductivity detection) wasdescribed. The CSF sample was pretreated with silver cation resin to remove high concentration ofCl- ions in CSF. The separation was achieved in the buffer solution of 10 mmol/L Tris and 8mmol/L boric acid at the separation voltage of 20.0 kV. Glu showed linear response in the range of5.0×10-6 to 6.0×10-3 mol/L, the limit of detection was 1.0×10-6 mol/L. The method was used foranalysis Glu in CSF satisfactorily with a recovery of 97.8-98.8%.

Boswellic acids: a review on its pharmacological properties, molecular mechanism and bioavailability

Boswellic acids is a general term for a series of pentacyclic triterpenoid compounds that are isolated from the oleogin resin of the Boswellia genus and serve as the main active ingredient.It exhibits a wide range of biological activities,such as anti-inflammatory,anti-cancer,antibacterial,antiviral,hepatoprotective,neuroprotective,anti-diabetic,and anti-thrombotic properties.As a result,it has gained significant recognition among practitioners of traditional Chinese and Indian medicine.These biological effects may be associated with multiple molecular targets and signal transduction pathways.However,the poor pharmacokinetic properties of the substance lead to lower bioavailability,which affects its effectiveness.To address this issue,scientists have proposed a number of strategies,such as solid dispersions,phytosome®technologies,and novel drug delivery systems.This article aims to provide a comprehensive overview for boswellic acids on the phytochemistry,molecular mechanisms,potential therapeutic applications,and strategies to improve bioavailability.

Exploring the targets and molecular mechanism of glycyrrhetinic acid against diabetic nephropathy based on network pharmacology and molecular docking

BACKGROUND Diabetic nephropathy(DN)stands as the most prevalent chronic microvascular complication of diabetes mellitus.Approximately 50%of DN patients progress to end-stage renal disease,posing a substantial health burden.AIM To employ network pharmacology and molecular docking methods to predict the mechanism by which glycyrrhetinic acid(GA)treats DN,subsequently validating these predictions through experimental means.METHODS The study initially identified GA targets using Pharm Mapper and the TCMSP database.Targets relevant to DN were obtained from the Genecards,OMIM,and TTD databases.The Venny database facilitated the acquisition of intersecting targets between GA and DN.The String database was used to construct a protein interaction network,while DAVID database was used to conducted Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis and Gene Ontology(GO)analysis.Molecular docking experiments were performed using Autodock software with selected proteins.Experimental validation was conducted using renal proximal tubular cells(HK-2)as the study subjects.A hyperglycemic environment was simulated using glucose solution,and the effect of GA on cell viability was assessed through the cell counting kit-8 method.Flow cytometry was employed to detect cell cycle and apoptosis,and protein immunoblot(western blot)was used to measure the expression of proteins of the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)signaling pathway and insulin resistance pathway,including insulin receptor(INSR),PI3K,p-PI3K,AKT,p-AKT,and glycogen synthase kinase-3(GSK3).RESULTS A total of 186 intersecting targets between GA and DN were identified,which were associated with 144 KEGGrelated enrichment pathways,375 GO biological process entries,45 GO cellular component entries,and 112 GO cellular function entries.Molecular docking demonstrated strong binding of GA to mitogen-activated protein kinase(MAPK)-1,SRC,PIK3R1,HSP90AA1,CASPASE9,HARS,KRAS,and MAPK14.In vitro experiments revealed that GA inhibited HK-2 cell viability,induced cell cycle arrest at the G2/M phase,and reduced apoptosis with increasing drug concentration.Western blot analysis showed that GA differentially up-regulated GSK3 protein expression,up-regulated AKT/p-AKT expression,down-regulated INSR,AKT,p-AKT,PI3K,and p-PI3K protein expression,and reduced p-PI3K/PI3K levels under high glucose conditions.CONCLUSION GA may protect renal intrinsic cells by modulating the PI3K/AKT signaling pathway,thereby inhibiting HK-2 cell viability,reducing HK-2 cell apoptosis,and inducing cell cycle arrest at the G0/G1 phase.

Research advances in phytochemistry,pharmacology and toxicology of oleanolic acid

Oleanolic acid(OA)is a pentacyclic triterpenoid chemical component that exists in natural plants with a molecular formula of C30H48O3 and a molecular weight at 456.71 g·mol-1.OA is widespread in traditional Chinese herbal medicine(Ligustri Lucidi Fructus,Achyranthis Bidentate Radix,Red Sage)and berries(blueberries,grapes).In recent years,because of the extensive pharmacological effects of OA,its advantages in disease treatment have become increasingly prominent and gradually attracted the attention of pharmaceutical researchers.OA has effective therapeutic effects on a series of chronic diseases such as inflammation,cancer,diabetes,and cardiovascular diseases through multiple signaling pathways and various targets.Especially in cancers,such as colorectal cancer,liver cancer,gastric cancer,lung cancer,breast cancer and other malignancies,OA presents substantial efficacy.However,its poor aqueous solubility,needy bioavailability,and unsatisfactory pharmacological activity excessively restrict its clinical application.More importantly,the improper utilization of OA can cause adverse reactions,toxic effects and even damage to organs in some specific situations.With the discovery of various pharmacological effects,the complex action mechanisms of OA,the continuous progress in structural modification of OA,as well as the synthesis of OA derivatives,its application is expanding gradually.Among numerous studies,there is a clear indication that OA and its derivatives,if fully developed,may provide an alternative and cheaper treatment for a variety of chronic diseases.However,the specific molecular mechanisms of OA and its derivatives as an alternative therapy and supplementary therapy for cancer,diabetes,cardiovascular disease and other chronic diseases remain to be clarified.Therefore,it is necessary to further study the pharmacokinetics,pharmacological activity,specific targets and related mechanisms of OA to lay a solid foundation for drug development and the application of OA in clinical settings.

Pathological Changes in Rabbit Retina and Its Relationship with Glutamic Acid after Injuries from High-Speed Bullets

Purpose:To observe the pathological changes in rabbit retinas and the measure of glutamic acid levels in the vitreous body after suffering from high-speed bullet injuries.Methods:Rabbits eyeball contusion models were established with high-speed bullets,i.e,the rabbits eyes were shot with a fixed air rifle at a speed of 90 m/s.(using plastic bullets,weighing 0.201 g,on average).Retinal tissues treated with HE staining and were prepared for light microscopy examination and glutamate levels were tested at different time points after the injury.Results:Edema,exudation,hemorrhage,and rupture were evident in rabbit retinas following bullet injuries.Meanwhile,glutamate levels gradually increased as time proceeded.Conclusion:Visual impairment is related with retinal damages after high-speed bullet injuries.Increased glutamate concentration serves as a potential factor for aggravating retinal injuries.

Increased excitatory amino acid transporter 2 levels in basolateral amygdala astrocytes mediate chronic stress–induced anxiety-like behavior

The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain function and encoding behaviors associated with emotions.Specifically, astrocytes in the basolateral amygdala have been found to play a role in the modulation of anxiety-like behaviors triggered by chronic stress. Nevertheless, the precise molecular mechanisms by which basolateral amygdala astrocytes regulate chronic stress–induced anxiety-like behaviors remain to be fully elucidated. In this study, we found that in a mouse model of anxiety triggered by unpredictable chronic mild stress, the expression of excitatory amino acid transporter 2 was upregulated in the basolateral amygdala. Interestingly, our findings indicate that the targeted knockdown of excitatory amino acid transporter 2 specifically within the basolateral amygdala astrocytes was able to rescue the anxiety-like behavior in mice subjected to stress. Furthermore, we found that the overexpression of excitatory amino acid transporter 2 in the basolateral amygdala, whether achieved through intracranial administration of excitatory amino acid transporter 2agonists or through injection of excitatory amino acid transporter 2-overexpressing viruses with GfaABC1D promoters, evoked anxiety-like behavior in mice. Our single-nucleus RNA sequencing analysis further confirmed that chronic stress induced an upregulation of excitatory amino acid transporter 2 specifically in astrocytes in the basolateral amygdala. Moreover, through in vivo calcium signal recordings, we found that the frequency of calcium activity in the basolateral amygdala of mice subjected to chronic stress was higher compared with normal mice.After knocking down the expression of excitatory amino acid transporter 2 in the basolateral amygdala, the frequency of calcium activity was not significantly increased, and anxiety-like behavior was obviously mitigated. Additionally, administration of an excitatory amino acid transporter 2 inhibitor in the basolateral amygdala yielded a notable reduction in anxiety level among mice subjected to stress. These results suggest that basolateral amygdala astrocytic excitatory amino acid transporter 2 plays a role in in the regulation of unpredictable chronic mild stress-induced anxiety-like behavior by impacting the activity of local glutamatergic neurons, and targeting excitatory amino acid transporter 2 in the basolateral amygdala holds therapeutic promise for addressing anxiety disorders.

Preparation and Evaluation of Poly-γ-Glutamic Acid Hydrogel Mixtures with Basic Drugs or Acidic Drugs: Effect on Ease of Swallowing and Taste Masking

The purpose of this study was to prepare a poly-γ-glutamic acid hydrogel (PGA gel), to examine its ease of swallowing using texture profile analysis (TPA) and to evaluate its taste-masking effects on basic or acidic drugs using the artificial taste sensor. Using TPA, 0.5% and 1.0% PGA gels, 0.5% and 1.0% agar and 1.0% ι-carrageenan in the absence of drug was examined the hardness, adhesiveness and cohesiveness, ranked according to permission criteria published by the Japanese Consumers Affairs Agency. 0.5% PGA gel and 1.0% agar were classified into grade II. In the taste sensor measurement, the bitterness suppressions by 0.5% PGA gel were larger than that by 1.0% agar in all drugs and the bitterness suppressions of basic drugs in 0.5% PGA gel were more potent than those of acidic drugs in 0.5% PGA gel. 1H-nuclear magnetic resonance spectroscopic analysis was carried out to examine the difference in mechanism of bitterness suppression between basic drugs and acidic drugs mixed with PGA gel. The signals of the proton nearest to the nitrogen atom of basic drugs shifted clearly upfield, suggesting an interaction between the amino group of basic drugs and the carboxyl group of PGA gel. In conclusion, PGA gel is expected to be a useful excipient in formulations contained various drugs, especially basic drugs;it also has advantage for not only increasing ease of swallowing but also masking the bitterness of drugs even though a small amount of a single drug dose might be preferred.

In Vitro Biomineralization of Glutaraldehyde Crosslinked Chitosan/Glutamic Acid Films

In vitro biomineralization of glutaraldehyde crosslinked chitosan/glutamic acid films were studied. IR and ESCA （electron spectroscopy for chemical analysis） determinations confirm that chitosan and glutamic acid are successfully crosslinked by glutaraldehyde to form chitosan-glutamic acid surfaces. Composite films were soaked in saturated Ca（OH）2 solution for 8 d and then immersed in simulated body fluid （SBF） for more than 20 d. Morphological characterizations and structure of cal-cium phosphate coatings deposited on the films were studied by SEM, XRD, and EDAX （energy dispersive X-ray analysis）. Initially, the treatment in SBF results in the formation of single-layer cal-cium phosphate particles over the film surface. As immersion time increases, further nucleation and growth produce the simulated calcium-carbonate hydroxyapatite coating. ICP results show Ca/P ratio of calcium phosphate coating is a function of SBF immersion time. The inducing of glutamic acid improves the biomineralization property of chitosan films.

Study on the Dissolution of Dusts in Glutamic Acid

This article describes the characteristics of natural dusts, artificial dusts and industrial dusts, such as mineral phases, chemical components, morphological observation and size. Quartz and calcite are the main phases of natural dusts and industrial dusts with high SiO2, CaO and low K2O, Na2O on the chemical composition. Natural dusts are mainly irregular shaped and some particle aggregation made of small dusts on the surface of large dust. Industrial dusts are globular and blob-like, but artificial dusts are columnar and fibrous. The fine particles are mainly in the range of 0.3-5 μm,of which the dusts of less than 5 μm are over 99%.The dissolution and electrochemical action of dusts in glutamic acid liquor at the simulated human body temperature (37 ℃) in 32 hours were investigated. The changes of pH values and electric conductivity of those dusts were similar, increased slowly in first 8 hours, and then the pH values increased rapidly. The total amount of dissolved ions of K, Ca, Na, Mg was 35.4-429 mg/L, particularly Ca was maximal of 20-334 mg/L. The total amount of dissolved ions of Fe, Zn, Mn, Pb, Ba was 0.18-5.59 ppm and the Al, Si was 3.0-21.7 mg/L. Each element dissolved rapidly relatively in first 16 hours. The relative solubility order of dusts in glutamic acid are: wollastonite > serpentine > sepiolite, the cement plant industrial dusts > power plant industrial dusts, and natural dusts have similar solubility. The wollastonite and power plant industrial dusts have highest solubility, which have high content of CaO; this shows there are a poorer corrosion-resisting ability and lower bio-resistibility. Sepiolite and cement plant industrial dusts have lowest solubility, which have high content of SiO2; this shows there are a higher corrosion-resisting ability and stronger bio-resistibility.

Double Labeling Immulloelectron Microscopic Study on the Synaptic Connections between Glutamic Acid Neurons and GABA Neurons in the Hippocampus of Rats

Summary: In order to explore the roles of different neurotransmitters in epileptic pathogenesis, the synaptic connections between glutamic acid (Gin) neurons and GABA neurons in normal rat hippocampus were studied by pre-embedding double labeling immunoelectron microscopy. The GABA immunoreaction was first demonstrated by chromogen DAB, then the Gin immunoreaction was demonstrated by molybdic acid-TAB method. After being stabilized by DAB-cobalt chloride. the sections were processed for electron microscopic embedding. Under electron microscope, there were many Gin immunoreaction-positive neurons in the pyramidal layer of hippocampal CA1 area and some GABA immunoreaction-positive neurons with pyramidal or polygonal perikarya in the pyramidal, polymorphic and radiant layer of CA1 area. There were also symmetric dendro-axonic synapses formed by GABA-positive dendrites and Glu-positive a-cons in the polymorphic layer and symmetric axo-dendritic synapses formed by GABA-positive axons and Glu-positive dendrites in the radiant layer. In addition, there were symmetric autoregulatory axo-dendritic synapses be- tween Gin-positive axons and dendrites and autoregulatory axo-axonic synapses (both symmetric and asymmetric) between GABA-positive axons. Above mentioned results, for the first time, showed that there were complex synaptic regulatory relationships between excitatory Glu neurons and inhibitory GABA neurons in the hippocampal CA1 area, thereby, providing ultrastructural evidence for different neurotransmitters participating in epileptic pathogenesis.

Determination of Enantiomeric Excess of Glutamic Acids by Lab-made Capillary Array Electrophoresis

Simulated enantiomeric excess of glutamic acid was determined by a lab-made sixteen-channel capillary array electrophoresis with confocal fluorescent rotary scanner. The experimental results indicated that the capillary array electrophoresis method can accurately determine the enanfiomefic excess of glutamic acid and can be used for high-throughput screening system for combinatorial asymmetric catalysis.

Development of a Freeze-Dried Skin Care Product Composed of Hyaluronic Acid and Poly(γ-Glutamic Acid) Containing Bioactive Components for Application after Chemical Peels

Eight types of spongy sheet were prepared by freeze-drying aqueous solutions of hyaluronic acid (HA) and poly(γ-glutamic acid) (PGA) with or without bioactive components including vitamin C derivative (VC), glucosylceramide (GC), and epidermal growth factor (EGF). Spongy sheets were categorized into the following groups: Group I (HA/PGA), Group II (HA/PGA + VC), Group III (HA/PGA + GC), Group IV (HA/PGA + VC, GC), Group V (HA/PGA + EGF), Group VI (HA/PGA + VC, EGF), Group VII (HA/PGA + GC, EGF), and Group VIII (HA/PGA + VC, GC, EGF). In the first experiment, we examined fibroblast proliferation in conditioned medium that had been prepared by immersing each spongy sheet in a conventional culture medium. EGF-incorporating spongy sheets (Groups V-VIII) enhanced fibroblast proliferation more than EGF-free spongy sheets (Groups I-IV). In the second experiment, cytokine production by fibroblasts was evaluated using a wound surface model. This involved elevation of fibroblasts-incorporating collagen gel sheets to the air-liquid interface, on which a spongy sheet (Groups I, IV, V and VIII) was placed and cultured for 1 week. EGF-incorporating spongy sheets (Groups V and VIII) enhanced the production of vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) by fibroblasts more than EGF-free spongy sheets (Groups I and IV). The effect of these four types of spongy sheet on wounds was investigated in animal experiments. Chemical peel was performed by contacting 50% trichloroacetic acid (TCA) on the dorsal region of mice, after which a spongy sheet was placed, and the wound condition was then observed in a two-week period. Angiogenesis was facilitated to a greater degree in Group VIII compared with Groups I, IV and V. This finding indicates that Group VIII spongy sheet is a promising aid for skin recovery after chemical peel.

Tb(lll) and Ca(ll) Ion Equilibria in the Presence of Glutamic Acid and Glutamine

Tb(111) and Ca(11) ion equilibria in the presence of glutamic acid and glutamine were studied by potentiometric titration at 37'C and an ionic strength of 0. 15mol/L(NaCl) .The stability constants for Tb(111) and Ca(11)complexes in the systems were obtained. The species and their distribution in the systems were discussed.