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  • Author: Jie Yu x
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Genetic diversity and structure among natural populations of Mytilaria laosensis (Hamamelidaceae) revealed by microsatellite markers

Abstract

Mytilaria laosensis is a fast-growing tropical broadleaf tree that is extensively used for wood production and has significant ecological benefits. To investigate the genetic diversity and population structure of M. laosensis, eight major natural popu­lations in China were analyzed by using simple sequence repeat (SSR) markers. A total of 88 microsatellite-containing fragments were obtained by the method of magnetic bead enrichment, among which 26 pairs of SSR primers were scree­ned out and used to generate a total of 190 alleles among 152 individuals. The average of observed number of alleles, Shannon’s information index and polymorphism information content per locus were 18.3, 1.1577 and 0.7759, respectively, implying a high level of genetic diversity in M. laosensis popu­lations. The variation within populations accounted for 81.74 % of total variation based on analysis of molecular variance. Clus­ter analysis divided the eight populations into four groups, among which five populations from the southern parts of Guangxi province were classified as one major group. Mantel test showed that there was highly significant correlation bet­ween Euclidean genetic distance and geographic distance, suggesting that geographic isolation contribute to the high genetic diversity of M. laosensis. Together, these could provide support for the feasibility of exploration and utilization of M. laosensis in subtropical areas of East Asia including Jiangxi, Hunan and Fujian province of China.

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Optimizing Signal De-Noising Algorithm for Acoustic Emission Leakage of Wavelet

Abstract

Traditional wavelet denoising method cannot eliminate complex high-pressure pipe signals effectively. In the updated wavelet adaptive algorithm, this thesis defines the constraints in order to reconstruct the signals accurately. According to the minimum mean square error criterion, the results predict the weight coefficient and get the optimal linear predictive value. Adopting the improved algorithm under the same condition, this thesis concluded that Db6 increased the complexity of wavelet algorithm by 50% by comparative experiments. It will be more conducive to the realization of hardware and the feasibility of real-time denoising. Dual adaptive wavelet denoising method improved SNR by 50%. This denoising method will play a key role in the detection rate of high-pressure pipe in the online leakage detection system.

Open access
Role of contrast-enhanced ultrasound in evaluating the efficiency of ultrasound guided percutaneous microwave ablation in patients with renal cell carcinoma

Abstract

Background. The aim of the study was to evaluate the efficiency and feasibility of contrast-enhanced ultrasound (CEUS) with Sonovue in assessing of renal cell carcinomas (RCCs) following ultrasound (US)-guided percutaneous microwave ablation (MWA).

Patients and methods. Seventy-nine patients (60 males and 19 females) with 83 lesions (mean size 3.2±1.6 cm) were treated by US-guided percutaneous MWA. The CEUS results of the third day after the ablation were compared with the synchronous contrast-enhanced computed tomography (CT)/magnetic resonance imaging (MRI) results and biopsy pathological results. The follow-up was performed by CEUS and CT/MRI after 1, 3, 6 months and every 6 months subsequently. The combination of clinical follow-up results and CT/MRI imaging findings was the reference standard of CEUS results for evaluating the therapeutic effect. The identification of residual or recurrence tumour was assessed by two blinded radiologists.

Results. On the third day after MWA, CEUS showed 68 of 83 lesions (68/83, 81.9%) successfully ablated and 15 of 83 (18.1%) with residual tumours. Among residual tumours, 13 (86.7%) were confirmed by contrast-enhanced CT/MRI findings and biopsy results. The sensitivity, specificity, accuracy, positive and negative predictive value of CEUS evaluating the short-term MWA effectiveness were 100%, 97.1%, 97.6%, 86.7% and 100%, respectively. During the six years follow-up (median 26 months), the CEUS showed recurrence in 7 patients, and six of them achieved consistent results on CEUS and CT/MRI imaging. The sensitivity, specificity, accuracy, positive and negative predictive value for CEUS evaluating long-term MWA effectiveness were 85.7%, 98.7%, 97.6%, 85.7% and 98.7%, respectively.

Conclusions. The post-procedural CEUS demonstrated as an effective and feasible method in evaluating a therapeutic effect of RCCs following MWA.

Open access
Duplex Quantitative Polymerase Chain Reaction of ISG15 and RSAD2 Increases Accuracy of Early Pregnancy Diagnosis in Dairy Cows

Abstract

Early diagnosis of pregnancy is important in livestock production, but there is no reliable technology used for pregnancy diagnosis within the first three weeks after insemination. During early pregnancy, the expression of interferon-stimulating genes (ISGs) in peripheral blood leukocytes (PBL) is significantly increased. However, due to different strains, detection sample types, detection methods, threshold value, etc. the specific effectiveness of early pregnancy diagnosis using ISGs is worth further study. The purpose of this study was to test interferon-stimulated protein 15 (ISG15), 2'–5'-oligoadenylate synthetase 1 (OAS1) and radical S-adenosyl methionine domain containing 2 (RSAD2) for early pregnancy diagnosis in dairy cows. The expression of ISG15, OAS1, and RSAD2 in PBL of pregnant and non-pregnant heifers on days 0, 14, 18, 21 and 28 after artificial insemination (AI) was detected by fluorescence quantitative polymerase chain reaction (PCR). The sensitivity and specificity of the pregnancy diagnosis was analyzed using expression of these three genes separately or in combination by receiver operating characteristic curve. The combination with the highest accuracy used probe primers and duplex fluorescence quantitative PCR. The single quantitative PCR results showed that expression of ISG15, OAS1 and RSAD2 on day 18 after AI was significantly higher in pregnant than in non-pregnant cows. When these three genes were used separately, or in combination, for early pregnancy diagnosis, the sensitivity for the RSAD2 gene was 100%, and the combination of ISG15 with RSAD2 was 94.7%. The duplex quantitative PCR showed that, although the sensitivity of ISG15 alone was 100%, its specificity was only 88.2% (cut-off value 1.402). The sensitivity of RSAD2 alone was 89.5%, and the specificity was 88.2%; however, when the two genes were used in combination, the sensitivity, specificity and diagnostic cut-off value were consistent with the results of single quantitative PCR. These results indicated that a duplex quantitative PCR assay system for early pregnancy diagnosis in cows using ISG15 and RSAD2 was established. Simultaneous detection of expression of ISG15 and RSAD2 by duplex quantitative PCR can effectively improve the diagnostic accuracy for dairy cows.

Open access
Detection of Mutations Resistant to Lamivudine or Adefovir in HBV and Its Management

Abstract

Objective Nucleos(t)ide analogues (NAs) naïve chronic hepatitis B(CHB) patients were given rescue combination therapy after drug resistance to lamivudine or adefovir. Evolution of HBV mutation patterns and its impact on antiviral effects were studied.

Methods Total of 142 naïve CHB patients treated with lamivudine were randomly divided into two groups when lamivudine resistance occurred. One group was added with adefovir, the other was switched to entecavir and adefovir. Seventy-two naïve CHB patients treated with adefovir were randomly divided into two groups when adefovir resistance occurred. One group was added with lamivudine, the other was added with entecavir. HBV polymerase reverse transcriptase mutations associated with resistance were analyed before and after 48 weeks of rescue therapy, respectively.

Results The mutation patterns of M204V/I, M204V+L180M were predominantly found in CHB patients after lamivudine resistance. Meanwhile, the entecavir resistance mutation patterns were also detected. Therefore, patients with lamivudine resistance could develop more diverse drug resistance mutations if they were switched to entecavir and adefovir. The mutation patterns of rtA181 were predominantly found in CHB patients after adefovir resistance and rescure therapy with add-on entecavir was more effective than with add-on lamivudine

Conclusions Resistance mutation analysis chould help to choose NAs, reduce resistance and ehance antiviral effects.

Open access
Detection and Clinical Significance of Circulating Microvesicles in Severe Fever with Thrombocytopenia Syndrome

Abstract

Objective Microvesicles (MV) released from blood cells play an important role in the progress of diseases. The purpose of this study is to detect circulating MV level of patients suffering from severe fever with thrombocytopenia syndrome (SFTS).

Methods The plasma samples of SFTS patients and healthy controls were collected. And MV from samples were isolated and MV levels were detected quantitatively.

Results The results showed that the level of the circulating MV in SFTS patients was obviously higher than that of the healthy control, with statistically significant difference. Further analysis revealed that MV level was relevant to the severity of SFTS patients, namely the higher the concentration of MV, the more severity of the disease. Linear correlation analysis showed that the circulating MV level in SFTS was correlated positively with leukocyte count (r = 0.243, P < 0.05), but no correlation with the platelet count (r = 0.193, P >0.05).

Conclusions We demonstrated that there existed high level of circulating MV in SFTS patients, and the level of circulating MV had a close relationship with the severity of the disease and leukocyte count. Therefore, monitoring the level of circulating MV may provide a new indicator for predicting the prognosis of SFTS patients.

Open access
Evaluation of long-term antibody response and cross-serotype reaction in ducks immunised with recombinant Riemerella anatipestifer outer membrane protein A and CpG ODN

Abstract

Introduction

Riemerella anatipestifer (RA) infections can lead to high mortality in ducklings. Inactivated vaccines against RA are commercially available, but they fail to provide cross-protection against various serotypes. We have previously demonstrated that a subunit vaccine containing recombinant outer membrane protein A (rOmpA) antigen of serotype 2 formulated with CpG oligodeoxynucleotides (ODN) as the adjuvant was able to stimulate both humoral and cellular immunities.

Material and Methods

In the present study, thirty healthy 7-day-old Pekin ducks were randomly assigned to three equal treatment groups: rOmpA-vaccinated, rOmpA + CpG-vaccinated, and control. Vaccine was injected intramuscularly and a booster dose of the same vaccine was given two weeks after primary immunisation. The long-term antibody response and cross-serotype reaction of this vaccine were evaluated in ducks.

Results

Compared to ducks immunised with rOmpA alone, ducks immunised with rOmpA + CpG ODN had significantly (p < 0.05) increased serum antibody titre from two weeks until nine months after primary immunisation. In addition, expression of cytokines including interferon (IFN)-α, IFN-γ, interleukin (IL)-6, and IL-12 was significantly (p < 0.05) enhanced in PBMC of ducks immunised with rOmpA + CpG ODN two weeks after primary immunisation. Antibodies from ducks immunised with the rOmpA + CpG ODN vaccine could also detect RA serotypes 1 and 6 in Western blot analysis.

Conclusion

Combination of rOmpA and CpG ODN could be a feasible strategy for developing a subunit RA vaccine with long term and broader-ranging protection.

Open access
MAMLD1 Gene Mutation in the Incidence of Hypospadias in the Chinese Population

Summary

Background: This study aimed to investigate the significance of MAMLD1 mutations in the incidence of hypospa-dias in a Chinese population.

Methods: The experimental group consisted of 150 domestic children with hypospadias, aged 0.5 to six years and living in different provinces. A total of 120 normal children, aged two to six years, served as the control group. DNA was extracted for the direct sequencing of MAMLD1 genes.

Results: Twelve cases (8.0%) of the missense mutation p.N589S were found in the experimental group, whereas four cases (3.0%) of the same mutation were found in the control group. No significant difference was observed in the mutation rate between the two groups (P>0.05). Four cases (2.7%) had a new missense mutation p.P567S in the experimental group, and three cases (2.5%) possessed the same mutation in the control group. No significant difference was observed between the two groups (P>0.05).

Conclusions: In this study, the importance of repeated experiments in mutation-related studies was confirmed, which revealed the difference in predisposing genes among different populations. Although the mutation of the MAMLD1 gene had no apparent connection with the incidence of hypospadias in a Chinese population, a new mutation site of the MAMLD1 gene was discovered, which could provide new research topics for future studies.

Open access
Electro-acupuncture on Nei Guan and Bai Hui: How Does It Affect GRP78 and Caspase-12 Gene Expression in Rats with Ischemia-Reperfusion Injury

Abstract

Objective: To observe the effects of electro-acupuncture (EA) on GRP78 and Caspase-12 gene expression in rats with ischemia- reperfusion injury (IRI) by stimulation on Nei Guan (PC6) and Bai Hui (GV20) points, so that to understand whether or not the protective effects of acupuncture is related to endocytoplasmic reticulum (ER) stressapoptosis passage.

Methods: 50 rats were randomly assigned to five groups (10 in each group): normal control(A), pseudo-operation(B), operation(C), Edaravone(D) and EA(E). The ischemia/reperfusion model of middle cerebral artery occlusion (MCAO) was established by suture embolic method. TUNEL staining method was employed to measure the apoptosis index of nerve cells in rats. Real-time polymerase chain reaction (RT-PCR) was employed to measure the mRNA expression of GRP78 and Caspase-12.

Results: Compared with normal group and pseudo-operation group, the apoptosis indexes and mRNA expression of GRP78 and Caspase-12 in operation group, Edaravone group and EA group were increased, with statistical significance(P<0.05 or P<0.01); compared with operation group, the apoptosis indexes and Caspase-12 mRNA expression in Edaravone group and EA group were decreased(P<0.05 or P<0.01), but GRP78 mRNA expression were increased(P<0.01); there were no significant difference between Edaravone group and EA group on the above indexes(P>0.05).

Conclusion: Acupuncture on Nei Guan and Bai Hui points could effectively suppress the nerve cell apoptosis in cerebral ischemia. The underlying mechanism might be related to upregulation of the ERS-protective GRP78 expression and downregulation of apoptosis-promotion Caspase-12 expression.

Open access