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Biomedical subjects

Hao Yang

Publications and source records attributed to Hao Yang.

At least 19 recordsLinked to original sources

Engineering CRISPR for Point-of-Care Tests.

CRISPR-based molecular diagnostics have emerged as powerful and programmable platforms that enable sensitive and specific detection for disease management and epidemiological surveillance. Advances in CRISPR engineering and assay design are driving the emergence of next-generation detection platforms that are highly sensitive, rapid, and amenable to field deployment. These engineering breakthroughs have the potential to reshape point-of-care tests (POCT) and transform how emerging and persistent health threats are monitored in decentralized and resource-limited settings. Herein, we systematically review the recent advancements in CRISPR engineering strategies aimed at improving detection sensitivity and specificity, eliminating the dependence on preamplification, and enabling robust POC deployment. The discussed strategies encompass both the rational engineering of CRISPR ribonucleoproteins (RNPs) and the optimization of downstream signaling modules for molecular diagnostic applications. We further highlight key challenges and future perspectives that may inspire impactful research directions and accelerate the advancement of CRISPR engineering strategies toward robust, field-deployable POCT platforms.

CRISPR-Cas Systems↗

MS4A3 as a potential prognostic biomarker for colon cancer: integrated analysis of expression patterns and immune cell infiltration.

BACKGROUND: Membrane Spanning 4-Domains A3 (MS4A3) has been confirmed to possess significant tumor-suppressive potential in various malignancies. However, its expression characteristics and clinical prognostic value in colon cancer (CC) still lack systematic and in-depth investigation. This study aimed to systematically investigate the expression pattern, prognostic value, immune microenvironment association, and biological function of MS4A3 in CC through integrated bioinformatics analyses and experimental validation. METHODS: This study utilized The Cancer Genome Atlas-Colon Adenocarcinoma (TCGA-COAD) cohort to screen for genes significantly associated with CC and combined multiple independent Gene Expression Omnibus (GEO) datasets to validate the expression patterns and prognostic significance of MS4A3. Key biological pathways were identified through gene set enrichment analysis (GSEA), and tumor immune infiltration characteristics were evaluated using the CIBERSORT algorithm. Additionally, the expression of MS4A3 and its impacts on cellular functions were validated at the cellular level through quantitative real-time polymerase chain reaction (qRT-PCR), Western blot, Cell Counting Kit-8 (CCK-8), EdU, Transwell, and TUNEL assays. RESULTS: Analysis of public datasets revealed that MS4A3 is significantly downregulated in CC tissues, and its low expression is an independent risk factor for shortened overall survival (OS). GSEA indicated that MS4A3 downregulation is closely associated with the aberrant activation of the pentose phosphate pathway. Immune infiltration analysis showed that low MS4A3 expression is closely linked to the enrichment of M2 macrophages and neutrophils, as well as the upregulation of multiple immune checkpoint genes. In vitro experiments further confirmed that MS4A3 was lowly expressed in CC cell lines. Its overexpression significantly inhibited CC cell viability, proliferation, migration, and invasion, while simultaneously promoting cell apoptosis. CONCLUSIONS: MS4A3 expression is significantly decreased in CC tissues and is significantly correlated with poor prognosis, suggesting that this gene may serve as a potential prognostic biomarker.

MS4A3↗

Extensive Recombination Suppression and Genetic Degeneration of a Young ZW Sex Chromosome System in Halfbeak Fish.

Sex chromosome systems have evolved independently across the tree of life, at different times in the past, and the evolutionary consequences of lacking recombination in sex-linked regions have been characterized in many old-established systems. However, empirical studies of young sex chromosomes are still scarce, especially in vertebrates. Integrating whole-genome sequencing data of two species of halfbeak fish, Hyporhamphus sajori and Hyporhamphus intermedius, we identified the sex-determining system in H. sajori as female heterogamety, involving a large fully sex-linked ZW region (∼26 Mb) on chromosome 5. The closest relative, H. intermedius, has a small sex-linked region on a different chromosome and shows male heterogamety, suggesting at least one turnover in this fish genus. The H. sajori sex-linked region includes two evolutionary strata, but the estimated Z-W divergence times are small, less than 3 million years for the older stratum, which is less than between the two species. Nevertheless, this evolutionarily young W-linked region is enriched with repetitive sequences, differs from the ancestral state by five inversions, and about one-third of its protein-coding genes have already become nonfunctional. Transcriptomic analysis suggests that some form of dosage compensation may already be evolving for some sex-linked genes.

Animals↗

Genome-wide Parallelism Underlies Rapid Freshwater Adaptation Fueled by Standing Genetic Variation in a Wild Fish.

A fundamental focus of ecological and evolutionary biology is determining how natural populations adapt to environmental changes. Rapid parallel phenotypic evolution can be leveraged to uncover the genetics of adaptation. Using population genomic approaches, we investigated the genetic architecture underlying rapid parallel freshwater adaptation of Neosalanx brevirostris by comparing four freshwater-resident populations with their common ancestral anadromous population. We demonstrated that the rapid parallel adaptation to freshwater followed a complex polygenic architecture and was characterized by genomic-level parallelism, which proceeded predominantly through repeated selection on the preexisting standing genetic variations. Frequencies of the genome-wide adaptive standing variations were moderate in the ancestral anadromous population, which had pre-adapted to fluctuating salinities. Relatively large allele frequency shifts were observed at some adaptive single-nucleotide polymorphisms (SNPs) during parallel adaptation to freshwater environments, with a large fraction of freshwater-favored alleles being fixed or nearly fixed. These adaptive SNPs were involved in multiple biological functions associated with osmoregulation, immunoregulation, locomotion, metabolism, etc., which were highly consistent with the polygenic architecture of adaptive divergence between the two ecotypes involving multiple complex physiological and behavioral traits. This work provides insight into the mechanisms by which natural populations rapidly evolve to changes in the environment and highlights the importance of standing genetic variation for the evolutionary potential of populations facing global environmental changes.

Animals↗

A simple parallel analytical method of prenatal screening.

Protein microarray has progressed rapidly in the past few years, but it is still hard to popularize it in many developing countries or small hospitals owing to the technical expertise required in practice. We developed a cheap and easy-to-use protein microarray based on dot immunogold filtration assay for parallel analysis of ToRCH-related antibodies including Toxoplasma gondii, rubella virus, cytomegalovirus and herpes simplex virus type 1 and 2 in sera of pregnant women. It does not require any expensive instruments and the assay results can be clearly recognized by the naked eye. We analyzed 186 random sera of outpatients at the gynecological department with our microarray and commercial ELISA kit, and the results showed there was no significant difference between the two detection methods. Validated by clinical application, the microarray is easy to use and has a unique advantage in cost and time. It is more suitable for mass prenatal screening or epidemiological screening than the ELISA format.

Dose-Response Relationship, Drug↗

Estrogen receptor alpha polymorphisms associated with susceptibility to hepatocellular carcinoma in hepatitis B virus carriers.

BACKGROUND & AIMS: Overexpression of estrogen receptors (ESRs) is implicated in the development of hepatocellular carcinoma (HCC) in both animal models and humans. We examined whether the ESR1 polymorphisms were related to HCC risk among chronic hepatitis B virus carriers. METHODS: Six ESR1 polymorphisms, which are (TA)n repeat in the promoter, T29C at codon 10 in exon 1, PvuII and XbaI site in intron 1, C136474G at codon 325 in exon 4, and A252966G in intron 5, were genotyped in 248 patients with HCC and 239 controls. The associations with the susceptibility to HCC were estimated by logistic regression. Allele-specific transcription difference of ESR1 messenger RNA was performed by real-time quantitative polymerase chain reaction. RESULTS: We observed a statistically significant increased susceptibility to HCC associated with the homozygous alleles with a high number of TA repeats (assigned as H/H genotype; odds ratio [OR], 2.66; 95% confidence interval [CI], 1.44-4.94; P = .0018), T29C C/C genotype (OR, 2.31; 95% CI, 1.25-4.26; P = .0076), and PvuII C/C genotype (OR, 2.19; 95% CI, 1.27-3.78; P = .0048) compared with the homozygous alleles with a low number of TA repeats (assigned as L/L genotype), T29C T/T, and PvuII T/T genotype, respectively. In accordance, the relative messenger RNA levels of the at-risk C allele of T29C were consistently higher than those of the T allele in heterozygous cells. CONCLUSIONS: Our findings suggest that the genetic polymorphism in ESR1 may play a role in mediating susceptibility to HCC in Chinese hepatitis B virus carriers.

Adult↗

Study of the antifungal ability of Bacillus subtilis strain PY-1 in vitro and identification of its antifungal substance (iturin A).

A Bacillus strain, denoted as PY-1, was isolated from the vascular bundle of cotton. Biochemical, physiological and 16S rDNA sequence analysis proved that it should belong to Bacillus subtilis. The PY-1 strain showed strong ability against many common plant fungal pathogens in vitro. The antibiotics produced by this strain were stable in neutral and basic conditions, and not sensitive to high temperature. From the culture broth of PY-1 strain, five antifungal compounds were isolated by acidic precipitation, methanol extraction, gel filtration and reverse-phase HPLC. Advanced identification was performed by mass spectrometry and nuclear magnetic resonance spectroscopy. These five antifungal compounds were proved to be the isomers of iturin A: A2, A3, A4, A6 and A7. In fast atom bombardment mass spectrometry/mass spectrometry collision-induced dissociation spectra, fragmentation ions from two prior linear acylium ions were observed, and the prior ion, Tyr-Asn-Gln-Pro-Asn-Ser-betaAA-Asn-CO+, was first reported.

Antifungal Agents↗

Fusion of fungicidal peptide dhvar4 to enterococcal peptide pheromone increases its bactericidal activity against Enterococcus faecalis.

Bacterial peptide pheromone has a high affinity to its membrane receptor. Fusion of these peptides to pore-forming antimicrobial peptide might enhance its bactericidal activity against pheromone-sensing bacteria. We constructed two chimeric peptides by fusing the pore-forming fungicidal peptide dhvar4 to the C-terminus of enterococcal peptide pheromones cCF10 and cOB1 individually. Comparison on the bactericidal activities against pheromone-sensing bacteria Enterococcus faecalis demonstrates that the chimeric peptides cCF10-dhvar4 and cOB1-dhvar4 are more potent than the parent peptide dhvar4. The LD(50)s of both chimeric peptides (1.0 microm) are 10 times lower than that of dhvar4 (10.8 microm). Free peptide pheromone could inhibit E. faecalis killing mediated by both chimeric peptides. As same as that of the parent peptide, both chimeric peptides kill bacteria by disrupting its cell membrane. These results indicate that fused enterococcal peptide pheromone increases the bactericidal activity of fungicidal peptide against E. faecalis by improving its ability to reach the cell membrane.

Anti-Bacterial Agents↗

[Changes of tight junction and Cx43 expression in microvessel endothelial cells of mouse lung induced by bleomycin].

OBJECTIVE: To investigate the changes of expression of connexin-43 (Cx43) and the tight junction of microvessel endothelial cells (EC) to approach the effects in bleomycin (BLM) induced pulmonary fibrosis (PF). METHODS: Forty healthy rats were equally and randomizedly divided into the control group and the experiment group. In both group, vWf in blood serum was measured with ELISA method on 3rd, 7th, 14th, 28th day after BLM treatment. Rats in each group were infused with lanthanum nitrate on 3rd, 7th, 14th, 28th day after BLM treatment. The lung samples were made and the tight junction and the distribution of the granules of lanthanum in the microvessel EC were observed with transmission electron microscopy in the control and experiment groups. The lung microvessel EC of the rats in each group were preserved by tissue culture methods at the same time, and the expression of Cx43 were observed by laser scanning confocal microscopy. RESULTS: The serum vWf in the peripheral blood of the experiment group was significantly higher than that of the control group, and was the highest on 3rd day after BLM treatment (P < 0.01). The blood vessel EC of the control group were intact. The basement membrane was uninterrupted. Granules of lanthanum nitrate did not penetrate the tight junction of EC. The width of junction gap in the experimental group was increased and the lanthanum granules of high density were found deposited in the linear form in the gap junction. Low expression of Cx43 was observed in experiment group. The expression rate of Cx43 was 25%, 38%, 45% and 71% respectively on 3rd, 7th, 14th, 28th day, significantly less than those in the control group (P < 0.05). CONCLUSION: It may be the important pathological basis for the BLM induced abnormality of the interstitial tissues in the lung that the tight junction of EC is continuously in the open state, which causes the effusions of inflammatory cells and the corresponding cytokine secretion, and thus initiates the overproliferation of fibroblasts.

Animals↗

[Effects of sense vascular endothelial growth factor cDNA transfection on mononuclear chemotaxis protein-1 expression in rat pulmonary microvessel endothelial cells].

OBJECTIVE: To study the transformation characteristics of tight junction of microvessel endothelial cells in bleomycin (BLM) induced pulmonary fibrosis (PF), and the effects of vascular endothelial growth factor (VEGF) on mononuclear chemotaxis protein-1 (MCP-1) mRNA expression in pulmonary microvessel endothelial cells (EC). METHODS: Forty healthy rats were equally divided into a control and an experimental group in random. In the experimental group, PF were induced by BLM application. In each group, 10 rats were instilled by lanthanum sal at 3, 7, 14 and 28 d after BLM application, and lung samples were made and observed by transmission electron microscopy. The pulmonary microvessel EC of the other 10 rats in each group were preserved by tissue culture methods at the same time, and the cells were transfected with sense VEGF cDNA, and then MCP-1 mRNA expression was detected by reverse transcriptase-polymerase chain reaction (RT-PCR) technique. RESULTS: Blood vessel endothelial cells of the control group were intact. The basement membrane was shown as a continuous line. Granules of lanthanum sal did not cross the tight junction of endothelial cells. The width of the junction gap in rats of the experimental group treated at different times was increased and lanthanum particles of high density were seen in the gap junction, particularly on day 3, and were distributed in the area of subendothelium. The MCP-1 mRNA expression in VEGF transfected microvessel EC was significantly higher than that of the control group (1.21 +/- 0.22 vs 0.36 +/- 0.06, P < 0.05). CONCLUSION: In BLM induced PF, the opening of the tight junction of EC, and the high expression of MCP-1 induce inflammatory cell infiltration and cytokine over-secretion, which in turn enhances proliferation of fibroblasts, one of the important factors underlying lung fibrosis.

Animals↗

[Evidence for the presence of motilin receptor and a study on the mechanism of motilin induced Ca2+ signaling in rat myenteric neurons].

OBJECTIVE: To observe whether the motilin receptor (MTLR) can be expressed in primarily cultured myenteric neurons of rats and investigate the mechanism of motilin induced Ca2+ signaling in myenteric neurons of rats. METHODS: Expression of the motilin receptor was identified with double-immunofluorescence staining technique. Data on the intracellular Ca2+ concentration ([Ca2+]i) of cultured myenteric neurons with different treatments were collected by measuring Ca2+ fluorescent intensity (FI) in each neuron under confocal microscope. RESULTS: The cultured myenteric neurons showed positive motilin receptor immunoreactivity. In Hank's solution, 10(-6) mol/L motilin could elevate [Ca2+]i, its height of peak being 30.6 +/- 3.7 and its FI relative change percentage being (100. 8 +/- 18.4)%. In D-Hank's solution (after removal of extracellular Ca2+, or after treatment with verapamil,an L-type calcium channel blocker), motilin could induce a small increase of [Ca2+]i. After pretreatment with NEM,a G protein inhibitor, and Compound 48/80, a PLC inhibitor, in Hank's solution respectively, motilin was inhibited and the [Ca2+]i was significantly lower than that of the group to which was added only motilin (P < 0.05). After pretreatment with D-sphingosine, a PKC inhibitor, the effect of motilin was not significantly different from that of the group to which was added only motilin (P > 0.05). CONCLUSION: The motilin receptor could be expressed by cultured myenteric neurons of rats. Motilin could increase [Ca+]i. The increase of [Ca2+]i was caused by release of intracellular stores and influx of extracellular Ca2+, mainly through the L-type calcium channel. The motilin receptor-coupled G-protein, PLC and IP3 pathway participated in the release of Ca2+ from intracellular stores.

Animals↗

[Dynamic analysis of heart rate variability based on wavelet transform].

The analysis of heart rate variability (HRV) has become a tool for noninvasively detecting the cardiovascular modulation of autonomic nervous system. Traditional analysis in frequency domain mainly includes calculating the power and detecting the peak frequency of each physiological frequency band. Whether employing the classical method or AR model to estimate the spectrum, the approximate stationarity of HRV is presupposed. Only in short term analysis can data meet this condition, while in long term the nonstationarity of HRV notably appears. A dynamic analysis method based on wavelet transform was proposed in this paper, which not only can obtain the traditional indices in frequency domain, but can compute their dynamic values varying with time, called short-time power and short-time LF/HF ratio. The latter can dynamically evaluate the activity of autonomic nervous. Finally the method was applied to trace the balance of autonomic nervous in Atropin drag experiment.

Adult↗

Association between mannose-binding lectin gene polymorphisms and susceptibility to severe acute respiratory syndrome coronavirus infection.

BACKGROUND: Genetic determinants of susceptibility to severe acute respiratory syndrome coronavirus (SARS-CoV) infection remain unknown. We assessed whether mannose-binding lectin (MBL) gene polymorphisms were associated with susceptibility to SARS-CoV infection or disease severity in an ethnically homogeneous population born in northern China. METHODS: The frequencies of 1 mutation in codon 54 and 3 promoter polymorphisms at nt -550, -221, and 4 were ascertained in 352 patients with SARS and 392 control subjects, by means of polymerase chain reaction direct sequencing. RESULTS: Of 352 patients with SARS and 392 control subjects, 120 (34.4%) and 91 (23.2%) were carriers of the codon 54 variant, respectively (odds ratio [OR], 1.73 [95% confidence interval {CI}, 1.25-2.39]; P=.00086). A total of 123 (36.0%) of 352 patients with SARS and 100 (25.5%) of 392 control subjects had haplotype pairs associated with medium or low expression of MBL (OR, 1.67 [95% CI, 1.21-2.29]; P=.00187). The population-attributable fraction of patients with SARS that was associated with having the codon 54 variant was 20.1% (95% CI, 7.9%-32.3%). CONCLUSIONS: MBL gene polymorphisms were significantly associated with susceptibility to SARS-CoV infection; this might be explained by the reduced expression of functional MBL secondary to having the codon 54 variant.

Alleles↗

[Study on the effect of composite of basic fibroblast growth factor and partially deproteinized bone on the repair of femoral head defects].

OBJECTIVE: To evaluate the effect of composite (bFGF/PDPB) of basic fibroblast growth factor (bFGF) and partially deproteinized bone (PDPB) on the repair of femoral head defect. METHODS: Forty-eight femoral heads with defect derived from 24 New Zealand rabbits were divided into 3 groups at random, which were implanted with bFGF/PDPB (group A), PDPB (group B) and nothing (group C) respectively. The rabbits were sacrificed at 2, 4, and 8 weeks after operation, and then the femoral heads were obtained. The specimens injected with Chinese ink were created. Then X-ray examination, histopathological and morphological examination of blood vessel, and image analysis were made. RESULTS: The bone defects healed completely 8 weeks after operation in group A. The implants in the repaired tissue were not substituted completely in group B. The bone defects did not heal completely in group C. Two weeks after operation, affluent newly formed vessels were seen in repaired areas in group A. No significant difference between group A and group B was observed 8 weeks after operation. In group C, newly formed vessels were scarce 2, 4, and 8 weeks after operation. There were 3 sides rated excellent, 2 good and 1 fair in group A; 1 excellent, 2 good, 2 fair and 1 poor in group B; and 1 fair and 5 poor in group C according to the X-ray evaluation 8 weeks after operation. Eight weeks after operation, the volume fraction of bone trabecula in repaired tissue was higher in group A than that in group B (P < 0.05), and the fraction in group C was the lowest among the 3 groups (P < 0.05). CONCLUSION: The composite of bFGF and PDPB can effectively promote the repair of femoral head defect of rabbit.

Animals↗

3-D model-based vehicle tracking.

This paper aims at tracking vehicles from monocular intensity image sequences and presents an efficient and robust approach to three-dimensional (3-D) model-based vehicle tracking. Under the weak perspective assumption and the ground-plane constraint, the movements of model projection in the two-dimensional image plane can be decomposed into two motions: translation and rotation. They are the results of the corresponding movements of 3-D translation on the ground plane (GP) and rotation around the normal of the GP, which can be determined separately. A new metric based on point-to-line segment distance is proposed to evaluate the similarity between an image region and an instantiation of a 3-D vehicle model under a given pose. Based on this, we provide an efficient pose refinement method to refine the vehicle's pose parameters. An improved EKF is also proposed to track and to predict vehicle motion with a precise kinematics model. Experimental results with both indoor and outdoor data show that the algorithm obtains desirable performance even under severe occlusion and clutter.

Algorithms↗

[Experimental study on repairing segmental bone defects with three bio-bone derived materials].

OBJECTIVE: To evaluate the osteogenesis of three bio-bone derived materials in repairing segmental bone defects. METHODS: Sixty Japanese rabbits were made 10 mm radius segmental defects and divided into 5 groups (groups A, B, C, D and E, n=12). Composite fully deproteinised bone (CFDB, group A), partially deproteinised bone (PDPB, group B), partially decalcified bone (PDCB, group C), autogenous iliac bone graft (group D) and no implant (group E) were implanted into the radius segmental bone defects of rabbits. The specimens were examined after 4, 8, 12 and 24 weeks; the osteogenesis was evaluated through X-ray radiograph and undecalcified solid tissue histological examination. RESULTS: The border between the material and host's bone was distinct after 4 weeks and blurred after 8 weeks; the density of partial edge of the material was similar to that of radii after 12 weeks. The medullary cavity of bone reopened in group B; the density of most defect area was similar to that of the host bone and there was a few high density shadow in group C; the density of most defect area was higher than that of host bone in group A after 24 weeks. There was no significant difference in radiograph scoring between groups A, B and C after 4 weeks and 8 weeks (P>0.05); the scores of group B and C were higher than that of group A after 12 weeks (P<0.05); and the scores were arranged as follow: group D > group B > group C > group A after 24 weeks (P<0.05). Bone callus grew toward defect area and new bone adhered to the material after 4 weeks and 8 weeks; more new bone formed, and the materials were absorbed and degraded with time. The quantity of bone formation was more in group D than in group B and in group B than in group C and in group C than in group A after 24 weeks (P<0.05). CONCLUSION: PDPB had good osteogenesis in repairing the segmental bone defect, PDCB was inferior to it, both PDPB and PDCB are fit to repair segmental bone defect. Both of them were inferior to autogenous bone.

Animals↗

[Culture, purification and biological characters of olfactory ensheathing cells from adult transgenic mice].

Several studies have demonstrated the potential of olfactory ensheathing cells (OECs) for the repair of central and peripheral nerve injury. In this work, ensheathing cells that express the receptor gene coding for enhanced green fluorescent protein (eGFP) from adult mice were isolated and purified, and then, its biological characters were examined in vitro. The work was based on combinations of fluorescence confocal, phase contrast, cell proliferation assay and immunolabeling identification. The results showed that (1) two major morphologically and immunohistochemically distinct types of cells were present after 15 days in the primary cultures of adult transgenic mice olfactory nerves and glomerular layers of the olfactory bulb. One cell type was bipolar or multipolar OECs and strained positively for P75 low affinity neurotrophic receptor (P75N), S100, and glial fibrillary acidic protein(GFAP). The other type was fibroblasts with flat or endothelial-like shape, and reacted with antibody against Thy1.1. (2) A simple, inexpensive method for purifying ensheathing cells, in which various harvested cell types showed different rates of attachment to the uncoated culture ware, was developed. This technique neither binds any antibodies nor requires any costly equipment, and yields a large number of highly purified cells. (3) In sequential observations over 22 days in culture, the population of purified cells was maintained and continued to proliferate for longer. This experiment not only supported and advanced the ensheathing cell research but also offered ideal materials of in vivo transplantation for the repair of CNS injury.

Animals↗

[Determination of amino acids in Isatis indigotica Fort by reversed-phase high performance liquid chromatography with pre-column derivatization].

A reversed-phase high performance liquid chromatographic method with pre-column derivatization for the determination of amino acids, which were known as the characteristic constituents of Isatis indigotica Fort was established. The amino acids in alkalescence were derivatized with 2, 4-dinitro-fluorobenzene (DNFB). A reproducible method for simultaneous qualitative analysis of glutamic acid (Glu), argirine (Arg) and proline (Pro) and quantitative analysis of Arg and Pro in Isatis indigotica Fort has been established. NaAc buffer (pH 6.4) acetonitrile (85:15, v/v) as mobile phase and a Sinochrom ODS-BP column were used. The detector was operated at 360 nm. The linear regressions of the standard curves were determined for Arg and for Pro. The method was carried out over the range of 0. 627 - 5.016 microg for Arg and 0. 874 - 7.000 microg for Pro. The recoveries were 98.5% and 98.4% with the relative standard deviations of 2.5% and 2.3% for Arg and Pro respectively. The results indicate that among the three amino acids in Isatis indigotica Fort, Arg content was the highest, Pro the second and Glu the lowest. The method has good accuracy and repeatability and it can be used for the quality control of Isatis indigotica Fort.

Amino Acids↗