Retracted: Pancratistatin Inhibits the Growth of Colorectal Cancer Cells by Inducing Apoptosis, Autophagy, and G2/M Cell Cycle Arrest.

An editorial decision has been made to retract this manuscript due to breach of publishing guidelines, following the identification of non-original and manipulated figures.Reference:Yong Xiong, Yi-Jia Xiong, Dong-Yang Liu, Rong-Rong Shen: Pancratistatin Inhibits the Growth of Colorectal Cancer Cells by Inducing Apoptosis, Autophagy, and G2/M Cell Cycle Arrest.Med Sci Monit 2019; 25:6015-6022. 10.12659/MSM.916116.

Improving Ion Selectivity of 1,4,7-Triazacyclononane-Based Receptor by Zinc Coordination: "Turn-On" Chemosensor for Br- and Fe3+ Ions.

Ion-responsive probes have gathered significant attention because of health and environmental factors, but there are few reports on the "turn-on" mechanism of Fe3+ and sensitive detection of Br- by fluorescence measurement. Herein, a green luminescence material, N-5-acetyl-2-hydroxy-benzamide-1,4,7-triazacyclononane (btacn), was successfully synthesized for the first time and comprehensively characterized. As expected, btacn exhibits high sensitive, but nonspecific, extensive interaction with Cu2+, Co2+, Zn2+, Mn2+, and Fe3+ ions. Therefore, to improve the specificity of the probe, we tried to synthesize transition metal complexes of btacn, but all failed except Zn(btacn)Cl2. In addition, the preformed complex, Zn(btacn)Cl2, was used as a special "turn-on" chemosensor for detecting trace amounts of Br- and Fe3+. The electrostatic interaction with Fe3+ and the hydrogen bond of PhO-H···Br- leads to obvious changes in the electronic cloud of Zn(btacn)Cl2, which are reflected in different spectral responses.

Pancratistatin Inhibits the Growth of Colorectal Cancer Cells by Inducing Apoptosis, Autophagy, and G2/M Cell Cycle Arrest.

BACKGROUND Worldwide, colorectal cancer is ranked as the third most prevalent cancer. The natural compound, pancratistatin, extracted from the spider lily, has previously been shown to target apoptosis in cancer cells lines. This study aimed to investigate the effects of pancratistatin in human colorectal cancer cells in vitro. MATERIAL AND METHODS Human colorectal cancer cell lines, including HTC-15 cells, were compared with a normal human colonic fibroblast cell line, CDD-18Co. Cells were treated with increasing doses of pancratistatin. The MTT assay was used to assess cell viability. Fluorescence microscopy using DAPI and Annexin-V/propidium iodide (PI) was used to detect cell apoptosis. Cell autophagy was detected by electron microscopy. Cell migration was evaluated using a wound healing assay, and Western blot determined the expression levels of cell cycle proteins. RESULTS Pancratistatin inhibited the growth of the colorectal cancer cells with an IC50 ranging from 15-25 µM, but had a limited effect in normal CCD-18Co cells, with an IC50 of >100 µM. Pancratistatin reduced HCT-15 cell migration. Growth inhibition due to pancratistatin was associated with morphological changes of HCT-15 cells and included autophagy and apoptosis, and increased expression the autophagic proteins, LC3II, beclin-1, and Bax. Pancratistatin induced arrest of HCT-15 cells at G2/M of the cell cycle and inhibited phosphorylation of cdc2/cyclin-dependent kinase 1 (CDK1) and Cdc25c and the expression of cyclin B1. CONCLUSIONS Pancratistatin inhibited the growth of colorectal cancer cells in vitro by inducing apoptosis, autophagy, and G2/M cell cycle arrest.

Isolation and genetic analysis of a variant porcine epidemic diarrhea virus in China.

Porcine epidemic diarrhea virus (PEDV) is having a severe effect on the pig breeding industry in central China. The mucosa and the content of the small intestine from newborn pre-weaned piglets with diarrhea were tested for the presence of PEDV by molecular and morphologic methods, and found to be positive. Negative-staining electron microscopy (EM) revealed the presence of coronavirus- like particles in the samples. The result of molecular detection by nested RT-PCR based on the amplification of the M gene was positive. Using a novel alternative method we successfully propagated the PEDV strain (CH/QX-2) in Vero cells, confirmed by ultrathin sections of the cells and Immunofluorescence assay (IFA). Phylogenetic analysis based on the partial S gene showed that the CH/QX-2 isolate was genetically closer to strains more commonly found in China, but differed genetically from two domestic strains (CH/S, 1986 and LZC, 2007), Korean strains (DR13, 2007), and the vaccine strain (CV777 vs) currently being used in China. CH/QX-2 formed a unique clade in the derived phylogenetic tree indicating that the CH/QX-2 strain currently circulating in central China is a new variant of PEDV. This study extends current knowledge on the diversity and epidemiology of PEDV.

Relationship between icotinib hydrochloride exposure and clinical outcome in Chinese patients with advanced non-small cell lung cancer.

BACKGROUND: The current study was conducted to explore the relationship between icotinib hydrochloride exposure and therapeutic effects in Chinese patients with advanced non-small cell lung cancer (NSCLC) who were treated with icotinib hydrochloride. METHODS: A total of 30 patients with NSCLC who were treated with icotinib hydrochloride were chosen from a single-center, open-label, phase 1 dose escalation clinical trial. Different doses of icotinib hydrochloride were administered orally for 28 consecutive days in different groups until disease progression or unacceptable toxicities occurred. Blood samples were collected during the first treatment cycle (day 1-28) for the pharmacokinetic analysis. Tumor responses were assessed according to the Response Evaluation Criteria in Solid Tumors (RECIST). The plasma concentrations of icotinib hydrochloride were assessed by liquid chromatography-mass spectrometry. RESULTS: Thirty patients with a median age of 56 years old (50% of whom were female) were enrolled. For single-dose treatment, the plasma pharmacokinetics demonstrated a median time to maximum concentration of 0.5 to 4 hours and a mean terminal elimination half-life of 6.21±3.44 hours at the 150-mg dose and 10.1±12.18 hours at the 200-mg dose. For multiple-dose treatment, the last measurable concentration (Clast ) was 708±368.67 ng/mL at the 150-mg every 12 hours, 782.73±618.18 ng/mL at the 200-mg every 12 hours, and 1162±658.44 ng/mL at the 125-mg every 8 hours; the under the concentration curve from time 0 to Clast was 14.5±2.43 hour*mg/mL, 13.2±2.5 hour*mg/mL, and 12.19±2.47 hour*mg/mL, respectively. At the dose of 150 mg every 12 hours, 1 patient with an epidermal growth factor receptor (EGFR) exon 19 deletion achieved a complete response for 10 months; another patient who carried the EGFR exon 19 deletion achieved stable disease for 6 months. Univariate analysis demonstrated that the time to maximum plasma concentration (Tmax ) after a single dose of icotinib hydrochloride was significantly correlated with the overall survival (OS) (Spearman correlation coefficient, 0.441; P = .012). The disease control rate was correlated with Tmax after a single dose (Spearman correlation coefficient, 0.518; P = .011). Multivariate analysis demonstrated that the area under the concentration-time curve from 0 to last determination time and the area under the curve from 0 to infinite time after a single dose of icotinib hydrochloride were correlated with OS (P = .037 and .042, respectively). The Clast was found to affect progression-free survival (P = .016). Stratification of these patients according to smoking status indicated significant correlation between OS and the area under the concentration-time curve from 0 to last determination time (Spearman correlation coefficient, -0.709; P = .015). CONCLUSIONS: Patients with a longer Tmax and higher exposure might experience longer OS and a higher disease control rate. In addition, the increased Clast might prolong the progressive-free survival of patients. However, the relationships between EGFR mutation, pharmacokinetics, and clinical outcomes require further research.

Pharmacokinetics and tolerability of olmesartan medoxomil plus hydrochlorothiazide combination in healthy Chinese subjects: drug-drug interaction, bioequivalence, and accumulation.

OBJECTIVES: The study is to investigate drug-drug interaction (DDI) between olmesartan medoxomil and hydrochlorothiazide (HCTZ), to confirm bioequivalence (BE) of a new combined formulation and coadministration of separate local tablets, and to receive pharmacokinetics and tolerability of the new combined formulation after multiple doses in healthy Chinese subjects. METHODS: The 3-in-1 study was separated into 2 stages. Stage 1 is a four-period crossover study. 28 healthy subjects were equally randomized into four groups. Each group received the four following regimens in a sequence as Latin square (4 × 4) design: A: olmesartan medoxomil; B: HCTZ; C: test drug (new combined formulation); D: reference drugs (co-administration of separate tablets). In stage 2, half of 28 subjects were daily dosed with regimen C for 7 days. Blood and urine samples were obtained to receive pharmacokinetics of olmesartan and HCTZ, which were analyzed using the BE evaluation method. Tolerability was also assessed. RESULTS: All subjects completed the study and nobody reported serious adverse event (SAE). The 90% confidence intervals (CI) of geometric mean ratio (GMR) of log transformed Cmax, AUC0-t, and AUC0-∞ after single dose showed no DDI and claimed BE. The mean ratio of accumulation (Ra) (SD) of olmesartan and HCTZ after multiple doses of new combination formulation is 1.03 (0.182) and 0.954 (0.128). CONCLUSIONS: No significant DDI between olmesartan and HCTZ was found. The new combination formulation is bioequivalent to co-administration of two separate local tablets. After multiple doses of the new combination formulation, no significant accumulation was observed. The new combination formulation is reasonably tolerated well in healthy Chinese subjects after multiple doses.

Pharmacokinetics, pharmacodynamics and toxicities of methotrexate in healthy and collagen-induced arthritic rats.

Methotrexate (MTX) is an anchor drug used to treat rheumatoid arthritis (RA), but responsiveness is variable in effectiveness and toxicity. Methotrexate and its polyglutamate conjugates (MTXPG(n)) in red blood cells (RBC) have been associated with patient response. In the current study, 13 collagen-induced arthritic (CIA) rats and 12 healthy rats were given subcutaneous doses of either saline or 0.3 or 1.5 mg/kg per 2 days of MTX from day 21 to 43 post-induction. Blood samples were obtained at various times to measure MTX in plasma, and MTX and MTXPG(n) in RBC. Effects on disease progression were indicated by body weight and paw size. After multiple-doses, RBC MTX reached steady-state (82.4 nm) within 4 days. The MTXPG(2) and MTXPG(3) in RBC kept increasing until the end of the study, attaining 12.5 and 17.7 nm. Significant weight loss was observed after dosing with 1.5 mg/kg/2 days, whereas moderate effectiveness was observed after dosing with 0.3 mg/kg/2 days. A pharmacokinetic/pharmacodynamic/disease (PK/PD/DIS) model with indirect mechanisms and transduction components incorporating plasma MTX, RBC MTX and RBC MTXPG(n) concentrations, and paw size was developed using naïve data pooling and ADAPT 5. The PK/PD in CIA rats dosed at 0.3 mg/kg/2 days were captured well by our proposed model. Methotrexate showed modest (I(maxd) = 0.16) but sensitive (IC(50d) = 0.712 nm) effectiveness on paw edema. The higher dose produced toxicity. The proposed model offers improved understanding of the effects of methotrexate on rheumatoid arthritis.

Portable Face-Shielding Device Based on sEMG Considering the COVID-19 Scenario.

Wearing a mask greatly reduced the possibility of infection during the COVID-19 pandemic. However, major inconveniences occur regarding patients with upper limb amputations, as they cannot independently wear masks. As a result, bacterial contamination is caused by medical staff touching the quilt when helping. Furthermore, this effect can occur with ordinary people due to accidental touch. This research aims to design an automatic and portable face shield assistive device based on surface electromyography (sEMG) signals. A concise face shield-wearing mechanism was built through 3D printing. A novel decision-making control method regarding a feature extraction model of 16 signal features and a Softmax classification neural network model were developed and tested on an STM32 microcontroller unit (MCU). The optimized electrode was fabricated using a carbon nanotube (CNT)/polydimethylsiloxane (PDMS). The design was further integrated and tested, showing a promising future for further implementation.

Effect of the CYP2C19 genotype on the pharmacokinetics of icotinib in healthy male volunteers.

PURPOSE: Icotinib hydrochloride {4-[(3-ethynylphenyl)amino]-6,7-benzo-12-crown-4-quinazoline hydrochloride}, a novel epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI), was designed for the treatment of non-small cell lung cancer (NSCLC). In the present study, we investigated the influence of the CYP2C19*2 and CYP2C19*3 alleles on the pharmacokinetics of icotinib in healthy Chinese volunteers. METHODS: In a single-dose pharmacokinetic study, 12 healthy Chinese volunteers received an oral dose of 600 mg of icotinib. Plasma was sampled for up to 72 h post-dose, followed by quantification of icotinib by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS-MS). RESULTS: Five subjects genotyped as homozygous extensive metabolizers (CYP2C19*1/*1), 6 subjects genotyped as heterozygous extensive metabolizers (CYP2C19*1/*2 or CYP2C19*1/*3), and 1 subject genotyped as a poor metabolizer (CYP2C19*2/*3) and was withdrawn from the research because of urticaria. The mean icotinib AUC(0-∞) and C(max) (14.56 ±5.31 h mg/L and 2.32 ± 0.49 µg/mL) in homozygous EMs was 1.56 and 1.41-fold lower than that in heterozygous EMs (22.7 ± 6.11 and 3.28 ± 0.48, P = 0.046 and 0.047). The mean CL/F (44.18 ± 12.17 L/h) in homozygous EMs was 1.55-fold higher than that in heterozygous EMs (28.42 ± 9.23 L/h, P = 0.013). CONCLUSIONS: The data showed that the pharmacokinetics of icotinib differ significantly between homozygous EMs and heterozygous EMs in CYP2C19.

A short deletion in the DNA-binding domain of STAT3 suppresses growth and progression of colon cancer cells.

In this study, we investigated the effect of a short deletion in the DNA-binding domain of STAT3 (STAT3del) on the transcriptional activation of STAT3 target genes and its relationship with colon carcinogenesis. We used the CRISPR-CAS9 gene editing system to delete a short sequence encoding amino acids 400-411 in the DNA-binding domain (amino acid sequence: 317-567) from STAT3 gene in SW480, SW620 and HCT116 colon cancer cells. ChIP sequencing analysis showed that STAT3del occupancy was significantly reduced in 1029 genes and significantly increased in 475 genes compared to wild-type STAT3. The mutation altered the DNA motifs recognized by STAT3del as compared to the wild-type STAT3. We observed a strong correlation between expression of the STAT3 target genes and the loss or gain of STAT3del binding to their promoters. CCK-8, wound healing, and TUNEL assays showed reduced proliferation, migration, and survival of SW480, SW620 and HCT-116 cells expressing STAT3del as compared to the corresponding controls. These findings demonstrate that a short deletion in the DNA-binding domain of STAT3 alters its genome-wide DNA-binding and transcriptional profile of STAT3-target proteins, and suppresses the growth, progression and survival of colon cancer cells.

Pulsed Radiofrequency of the Trigeminal Ganglion for Treating Postherpetic Neuralgia of the Ophthalmic Branch.

Postherpetic neuralgia (PHN) is a painful, long-lasting condition as a consequence of nerve damage resulting from a herpes zoster infection. Although there are many different treatments available to reduce pain duration and severity, PHN is often refractory to them and no single therapy shows an effective cure for all cases of PHN, especially for those involving the ophthalmic branch of the trigeminal nerve. Pulsed radiofrequency (PRF) is a minimally invasive procedure for pain treatment that has been practiced over the past decade. However, its clinical efficacy and safety for treating PHN involving the ophthalmic branch of the trigeminal nerve have not been evaluated. Objective. This study aimed to evaluate the efficacy and safety of PRF for treating PHN involving the ophthalmic branch of the trigeminal ganglion. Study Design. An observational study. Setting. All patients received PRF of the ophthalmic branch of the trigeminal nerve, pain intensity was assessed by a visual analogue scale (VAS), and complications before and after PRF stimulation were noted. Methods. Thirty-two patients with PHN of the ophthalmic branch were treated by PRF of the ophthalmic branch with controlled temperature at 42°C for 8 min. Pain relief, corneal reflex, sleep quality, and satisfaction were assessed for all patients. Results. Thirty out of 32 patients (93.75%) reported significant pain reduction after PRF treatment. Twenty-eight of them (87.5%) were satisfied with their sleep and obtained a pain score lower than 3 following the procedure. Only two patients had a recurrence of the severe burning pain and returned to the hospital for other medical therapies 2 weeks after the PRF procedure. No patient lost the corneal reflex. Limitations. This study is an observational study and a nonprospective trial with a short-term follow-up period. Conclusion. PRF of the trigeminal ganglion of the ophthalmic branch can significantly reduce pain sensation and improve sleep quality and satisfaction for PHN of the ophthalmic branch.

Corrigendum to "Pulsed Radiofrequency of the Trigeminal Ganglion for Treating Postherpetic Neuralgia of the Ophthalmic Branch".

[This corrects the article DOI: 10.1155/2021/6638392.].

Subcutaneous Peripheral Nerve Stimulation for Treatment of Acute/Subacute Herpes Zoster-related Trigeminal Neuralgia: A Retrospective Research.

OBJECTIVES: The purpose of this study was to observe the effect of subcutaneous stimulation of the peripheral nerve on acute or subacute zoster occurring in trigeminal nerve branches, and to evaluate the preventive effect of prior temporary implant of a peripheral stimulation electrode in the acute or subacute phase of herpes zoster (HZ) (from 30 to 90 d after zoster onset) before postherpetic neuralgia (PHN) presents. METHODS AND MATERIALS: A total of 26 patients' medical records were analyzed. All of patients had received temporary subcutaneous peripheral nerve stimulation (PNS). The clinical efficacy of treatment was evaluated on a visual analog scale (VAS), and dosages of pain medication were recorded before and at 1 to 6 months after the temporary stimulation. The rate of PHN was reevaluated at a 6 months follow-up. RESULTS: There was a significant decrease in VAS values after PNS. Medication doses decreased significantly after TPNS. The rate of clinically meaningful PHN (VAS >3) dropped below 4%. DISCUSSION: This study revealed that PNS is an effective treatment for trigeminal herpetic neuralgia following acute or subacute HZ. As a extend neuromodulation method, subcutaneous peripheral nerve-field stimulation might be a useful option to reduce the progression of neuropathic changes caused by persistent transmission of pain signals in the trigeminal nerve branches after the acute or subacute phase of HZ.

Characterization of a cryptic plasmid pPZZ84 from Bacillus pumilus.

The complete nucleotide sequence of a cryptic plasmid pPZZ84 from Bacillus pumilus strain ZZ84 was determined. Plasmid pPZZ84 is 6817bp long with GC content of 36.7%. Seven putative open reading frames were identified. ORF7 shows 91% and 90% amino acid identity with rep proteins of pSH1452 and pPL1, respectively, members of rolling-circle replication (RCR) pC194-family. A typical pC194-family double strand origin (dso), a single-stranded origin (sso) and rap (regulator aspartate phosphatase) proteins were also identified in the plasmid. These results imply that pPZZ84 belongs to the Bacillus subtilis species group of small rolling circle (BsSRC) replicating plasmids. The plasmid copy number of pPZZ84 in B. pumilus ZZ84 was estimated to be 46 per cell, more than that of other BsSRC plasmids in their hosts.

Growth of in vitro Fusarium oxysporum f. sp. niveum in chemically defined media amended with gallic acid.

Gallic acid was artificially added to the media to grow Fusarium oxysporum f.sp.niveum to investigate its effect on the pathogenic fungus. Results indicate that gallic acid inhibited the growth of F. oxysporum f.sp.niveum. The colony diameter, the conidia germinating rate and the conidia yield were reduced by 5.7-22.9%%, 35.8-55.6% and 38.9-62.2% respectively. However, the virulence factors by the fungus were stimulated. The activity of pectinase, proteinase and cellulase increased by 12.3-627.8%, 11.8-41.2% and 0.5-325.0% respectively, while the activity of amylase increased slightly. The results suggest that gallic acid repressed growth but facilitated the relative pathogenicity of invading pathogens.

Dynamics of metal(loid) resistance genes driven by succession of bacterial community during manure composting.

Metal(loid) resistance genes (MRGs) play important roles in conferring resistance to metal(loid)s in bacterial communities. How MRGs respond to bacterial succession during manure composting remains largely unknown. Metagenomics was used in the present study to investigate the compositional changes of MRGs, their candidate hosts and association with integrons during thermophilic composting of chicken manures. MRGs conferring resistance to 20 metal(loid)s were detected, and their diversity and abundance (normalized to the abundance of 16S rRNA genes) were significantly reduced during composting. MRGs associated with integron were exclusively observed in proteobacterial species. Class 1 integron likely played an important role in maintaining mercury-resistance mer operon genes in composts. Escherichia coli harbored the most abundant MRGs in the original composting material, whereas species of Actinobacteria and Bacilli became more important in carrying MRGs during the late phases. There were significant linear relationships between the relative abundance of some specific bacterial species (E. coli, Actinobacteria species and Enterococcus faecium) and the abundance of MRGs they potentially harbored. The succession of these bacteria contributed to an overall linear regression between the relative abundance of all predicted candidate hosts and the abundance of total MRGs. Our results suggest that the succession of bacterial community was the main driver of MRG dynamics during thermophilic composting.

Effect and safety of roflumilast for chronic obstructive pulmonary disease in Chinese patients.

BACKGROUND: This trial aimed to evaluate the efficacy and safety of roflumilast for treating Chinese patients with chronic obstructive pulmonary disease (COPD). METHODS: A total of 120 patients with COPD were recruited and were randomly divided into 2 groups (an intervention group and a placebo group) at a 1:1 ratio. Patients received either roflumilast or placebo 500 µg once daily for a total of 12 months. The primary outcome was lung function, measured by the change from baseline of forced expiratory volume in 1 second (FEV1), FVC = forced vital capacity (FVC), and FEF25-75%. The secondary outcome measurements included the quality of life, measured with the St. George's Respiratory Questionnaire (SGRQ). All outcomes were measured at the end of 12-month treatment and 3-month follow-up after the treatment. In addition, adverse events (AEs) were also recorded during the treatment period. RESULTS: FEV1, FVC, FEF25-75%, and SGRQ were significantly better in the intervention group than those in the placebo group at the end of 12-month treatment and 3-month follow up after treatment. Moreover, AEs were much higher with roflumilast than placebo in this study. CONCLUSIONS: The findings suggest that roflumilast has promising effect to improve lung function in Chinese population with COPD.

[Development of a new type of biological organic fertilizer and its effect on the growth promotion of tomato]. / æ–°åž‹æœ¨éœ‰æ°¨åŸºé ¸æœ‰æœºè‚¥ç ”åˆ¶åŠå ¶å¯¹ç•ªèŒ„çš„ä¿ƒç”Ÿæ•ˆæžœ.

The objective of this study was to improve the ability of sporulation production of Trichoderma guizhouense NJAU4742 under solid state fermentation by using rice straw and amino acids as resources, and the fermentation products were used as inoculants of the organic fertilizers adding with different ratios of amino acids solution to develop a new type of biological organic fertilizer. The results indicated that the optimal condition for sporulation by T. guizhouense NJAU4742 was soaking in 30 times diluted amino acid solution for one whole night, with initial pH 3.5, 75% of moisture content and 30% of corn powder, under which the sporulation reached to 2.40×1010 CFU·g-1. The fermentation products were inoculated at 2% into the mature organic fertilizer containing 20% of amino acids solution, and the sporulation and IAA content were 6.40×109 CFU·g-1 and 38.66 mg·kg-1, which were 1142.30 and 1.42 times higher than that of CK after 7 days, respectively. Pot experiment showed that biological organic fertilizer could significantly promote the growth of tomato, and the height of the tomato increased by 98.8% and 23.8%, respectively, compared with CK. The stem diameters of AT (amino acids + mature organic fertilizer + T. guizhouense NJAU4742) and AA (amino acids + mature organic fertilizer) were increased by 58.9% and 10.3%, respectively, compared with CK. As for the chlorophyll, leaf length and leaf width, the values also increased significantly. The highest spore content was obtained by using amino acids and rice straw as substrates under solid state fermentation (SSF), which overcame the difficulties of producing new type of biological organic fertilizer during the large scale industrial production. Biological organic fertilizer and amino acids organic fertilizer could significantly promote the growth of tomato compared with the chemical fertilizer, and had a good application prospect in intensive agriculture.

[Studies on population difference of Dendrobium officinale II establishment and optimization of the method of ISSR fingerprinting marker].

OBJECTIVE: To establish and optimize ISSR-PCR system of Dendrobiwn officinale according to the ISSR-PCR characters of D. officinale. METHOD: The effects of ISSR-PCRs was examined by selecting primers and designing different concentrations of the factors in the ISSR-PCRs, the reliable ISSR-PCR systems for D. officinale populations researching was established by analyzing the reasons for occurrence of differential bands and optimizing reaction conditions. RESULT AND CONCLUSION: The optimal ISSR-PCR system in D. officinale was reported for the first time, and 25 15327012 microL ISSR-PCR system contained 10 x Taq buffer, 1.5 U Taq DNA polymerase, 1.2-1.8 mmol x L(-1) MgCl2, 80 micromol x L(-1) dNTP, 0.2 micro mol x L(-1) primer and 20 ng template DNA. The appropriate annealing temperature was among 52-60 degrees C. ISSR PCRs were significantly influenced by Taq DNA polymerase, template DNA quantity and annealing temperature, etc. The ISSR-PCR systems, which were established in this paper for studying D. officinale, could provide clear reliable abundant polymorphisms molecular markers and were proved suitable for studying population authentication and population molecular ecology of D. officinale.

[Genetic diversity and molecular authentication of wild populations of Dendrobium officinale by RAPD].

AIM: Genetic diversity, relationship and molecular authentication of total 8 wild populations of Dendrobium officinale were investigated using RAPD markers. METHODS: 10 random decamer primers were screened for Random Amplified Polymophic DNA (RAPD) fragments. A DNA molecular dendrogram was established based on cluster analysis by UPGMA (unweighted pair-group method with arithmetic average), and the relationship of the wild populations were analyzed, and all the wild populations were authenticated. RESULTS: A total of 439 loci with an average of 43.9 loci per primer and 54.9 loci per population were amplified from 8 wild populations by 10 effective primers. In the total 104 amplified bands, 95 were polymorphic, corresponding to 91.35% genetic polymorphism. The genetic distances were 0. 590 to 0. 727, with an average of 0. 686. CONCLUSION: Distinct genetic differences and extensive genetic diversity were presented among the wild populations. RAPD markers were an informative and useful tool for the genetic diversity, evaluation and authentication of wild populations of Dendrobium officinale. Primer S412 could be used to authenticate 8 wild populations completely.