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Open access

Hua Feng

Abstract

In recent years, owing to abuse of antibiotics, extensive use of antitumor drugs and immunosuppressive agents and other reasons, an increasing number of people suffered from fungal infection. In this situation, researchers proposed new diagnosis methods, such as G test, galactomannan (GM) test, and polymerase chain reaction (PCR). G test is simple, quick, and highly sensitive and can detect multiple fungi; however, it cannot distinguish fungal types and may result in false positive and false negative results. GM test is less time consuming and feature highly positive detection rates but can simply be used in inspection of invasive aspergillosis. However, optimal positive critical values of GM test remain controversial. PCR is currently one of the fastest methods but is not formally used in clinical practice because of its lack of standardized operation and evaluation criteria. This study reviews the above three methods with the aim of discovering and summarizing their advantages and disadvantages to facilitate research and development of new diagnosis methods.

Open access

Hua Feng

Abstract

Helicobacter pylori (Hp) is one of the most common human pathogens. The infection caused by this bacterium is closely related to various clinical diseases. However, the eradication rate of conventional quadruple therapy has decreased, but the recurrence rate of infections has increased. The oral cavity is another major storage of Hp in addition to the stomach, and a certain homology exists between Hp in the oral cavity and Hp in the stomach. Periodontal treatment has a certain role in the killing of oral Hp, which can increase the eradication rate and reduce the recurrence rate of Hp in the stomach. This article summarizes the influence of oral Hp on the eradication rate and recurrence rate of gastric Hp.

Open access

Hua Feng, Chungkun Shih, Dong Ren and Chenxi Liu

New male pelecinid wasps (Hymenoptera: Pelecinidae) from the Yixian Formation of western Liaoning (China)

Two new genera and species Abropelecinus annulatus gen. et sp. nov. and Azygopelecinus clavatus gen. et sp. nov., placed in the subfamily Iscopininae of the family Pelecinidae, are described and illustrated. Sinopecinus viriosus Zhang, Rasnitsyn & Zhang, 2002 are re-described. All these male specimens were collected from the Yixian Formation of Beipiao City, Liaoning Province, northeastern China. A key to the male species of the subfamily Iscopininae is given. In addition, sexual dimorphism in Pelecinidae and the paleoclimate of the Yixian Formation are briefly discussed.

Open access

Li Hua-Wu, Ma Hong-Xing, Jiang Jian-Feng, Yang Xi-Jun and Yang Xing-Hua

Abstract

With the continuous increase of output power ratings, multi-phase (multichannel) interleaved power factor corrector (IPFC) is gradually employed in domestic and commercial inverter air-conditioners. IPFC can solve several main problems, such as power rating increase, power device selection, input current ripple reduction as well as inductor on-board mounting. But for a multi-phase IPFC, the key problem is that it should show rapid dynamic responds and good current sharing capability, so in this paper the aim is to improve the dynamic performance and current sharing capability by means of passivity control theory. Considering the power circuit topology of a four-phase IPFC, an EL (Euler-Lagrange) mathematical model is established when the IPFC operates in continuous conduction mode (CCM). Then the passivity of the four-phase IPFC is proved, and the passivity-based controller using the state variables feedback and damping injection method is designed. The proposed control scheme, which is easy to control and needs no proportion integral controller, has strong robustness on disturbance from singlephase AC input voltage, the load as well as the parameters of the employed devices. Even in wide-range load condition, the mains current has a fast dynamic response and the average output voltage almost keep unchanged. As a result, the main functions of the four-phase IPFC are implemented including nearly unitary power factor and constant DC output voltage. Meanwhile, the four-phase IPFC acquires an excellent current sharing effect after using passivity-based controller. The above analysis has been proved with simulated results by means of MATLAB/SIMULINK and experimental results, showing that the passivity-based IPFC controller has superior performances and feasibility.

Open access

J. Hua, X. Lin, W. Shen, R. Yin and Y. Feng

Abstract

A pot culture experiment was carried out to study the effects of land use history and inoculation with Fusarium oxysporum f. sp. cucumberinum Owen (Foc) on soil nematodes communities during the cucumber growing season in 2007. The results showed that land use history and inoculation had significant effects on the abundance and diversity of soil nematodes. Bacterivores were found to be the most dominant group in this study. Irrespective of inoculation, numbers of fungivores, plant-parasites and values of trophic diversity index (TD) and plant-parasites index (PPI) were greater in greenhouse soils (GH) than in open field vegetable soils (OF) during the growth period of cucumber. While, the number of omnivores-predators and values of richness (SR) and maturity index (MI) presented an opposite trend. Foc inoculation had noticeable effects on numbers of plant-parasites and some taxa, such as Helicotylenchus, Epidorlaimus at flowering stage and Aphelenchus, Tobrilus at fruiting stage. Besides, inoculation significantly affected values of PPI at flowering stage and TD at fruiting stage, respectively. The faunal analysis showed that soil food web in GH was highly disturbed and in OF was degraded.

Open access

Hua Mao, Deng-feng Jiang and Li-yun Huang

Abstract

Objective To detect the values of NT-proBNP and evaluate its relationship with liver function, cardiac structure, and cardiac function which was evaluated by echocardiography in patients with liver cirrhosis.

Methods A total of 50 liver cirrhotic patients and 11 healthy controls were studied by two dimensional Doppler echocardiography. Liver cirrhotic patients were divided into group A, B and C according to the Child-Pugh score. Cardiac dimensions and left and right ventricular functions were also evaluated. At the same time, the serum NTproBNP of liver cirrhotic patients and healthy controls were detected, respectively.

Results By Comparison between two groups, we found that the values of LVd, LAs, LVPW, AAO, A Wave, RVOTs, PV and NT-proBNP in liver cirrhosis group were higher than those in control group, whereas the value of E/A decreased. As for the value of LAs and serum NT-proBNP, A and B group were all lower than C group. With LAs > 35 mm, the number of cases in liver cirrhosis group was higher than that in control group. So did that With E/A < 1.

Conclusions The cardiac dysfunction confirmed the existence of cirrhotic cardiomyopathy. More clinical implications were found in liver cirrhotic patients with increased values of serum NT-proBNP.

Open access

Lei Feng, Xiaoping Zhang, Hui Hua, Liying Qiu, Lianfen Zhang and Zhongwei Lv

Abstract

Background: Study of antiangiogenic drugs is one of the cutting-edge fields in new antitumor drug development. However, system studies on Vaccaria segetalis extract as an inhibitor of tumor-induced neovascularization have not been published yet. In the current study, we performed a preliminary investigation of the antiangiogenic effect of Vaccaria segetalis extract on angiogenesis.

Objective: We studied the inhibitory effect of Vaccaria segetalis extract on neovascularization.

Methods: The effects of Vaccaria segetalis extract on in vitro proliferation, migration, and tube formation of human mammary endothelial cells (HMECs) were determined by 3 - (4,5) - dimethylthiahiazo (-z-y1) - 3, 5 -diphenytetrazoliumromide (MTT) assay and Matrigel plug assay. The antiangiogenic effect of Vaccaria segetalis extract was observed on the chick chorioallantoic-membrane (CAM) angiogenesis model. The CD31 expression on HMECs was detected by immunohistochemical staining. The therapeutic effect of Vaccaria segetalis extract on the metastasis of Lewis lung cancer was also observed in the mouse model.

Results: The proliferation and migration of human mammary epithelial cells (HMECs) were inhibited significantly by Vaccaria segetalis extract in a dose-dependent manner (IC50 = 50 μg/mL). Angiogenesis was also inhibited in the Matrigel-plug mouse model and the chick chorioallantoic-membrane model. The Vaccaria segetalis extract treatment reduced the expression of CD31 in HMECs and inhibited the growth and metastasis of Lewis lung carcinoma cells in the mouse model.

Conclusion: The Vaccaria segetalis extract, which can obviously inhibit angiogenesis, could be developed as a promising new antiangiogenic drug.

Open access

Cheng-bao Wang, Jian-jie Chen, Hong-ming Nie, Feng Gao, Hua Lv and Hong-ding Li

Abstract

Objective This study was undertaken to investigate the influencing factors on serum ALT level and hepatitis C virus (HCV) RNA titer in chronic hepatitis C (CHC) patients.

Methods All patients enrolled into this study were anti-HCV positive. Retrospective tracing method was applied to detect serum ALT level and HCV RNA titer and to collect general information of the patients such as genders, age groups, interferon medication history, infection pathways, height and weight. Then the multi-factor analysis was adopted with the application of binominal logistic regression mode.

Results The abnormal rate of ALT level was positively correlated to HCV RNA and gender while negatively correlated to interferon medication history and age group, with Wald value of the 4 factors as 39.604, 11.823, 18.991 and 7.389, respectively. The positive rate of HCV RNA was negatively correlated to interferon medication history and gender while positively correlated to ALT level, with corresponding Wald value of the 3 factors as 81.394, 7.618 and 27.562, respectively.

Conclusions The normal ALT level in HCV infected patients was associated with viral load, age, gender and interferon medication history, while the normal rate of HCV RNA titer was closely associated with gender, interferon medication history and ALT level.

Open access

Jing Du, Lian Fang Du, Feng Hua Li, Xiao Zhi Zheng, Hong Li Li, Qiu Sheng Shi and Ying Wu

Abstract

Background: Ocular disorders have greatest potential for benefit from gene therapy. The major obstacle in the clinical application of gene therapy is not due to the lack of an ideal gene, but rather the lack of a clinically safe and efficient gene transfer method. Ultrasound (US) targeted microbubble destruction (UTMD)-mediated gene delivery system as a noninvasive gene transfer method is now widely used in gene therapy of cardiovascular disease, muscular tissue, and tumor, and proved to effectively enhance gene transfer in various studies in vitro and in vivo. However, it is just the beginning of application for ophthalmological disease.

Objective: Review the latest advancements in UTMD-mediated ocular gene transfection and discuss mechanisms of UTMD involved in gene transfection, obstacles, and limitations to the use of this technology, as well as the perspectives for future applications of UTMD-mediated gene delivery system.

Methods: Summarize published literature concerning UTMD-mediated ocular gene transfection.

Results: UTMD is an effective and safe gene delivery method of therapy for ocular diseases. Considerable progress has been made in US or UTMD-mediated viral and nonviral ocular gene delivery to retina, like recombinant adeno-associated virus (rAAV) and nanoparticles as nonviral gene carriers. In addition, UTMD has potential for producing the blood-retinal barrier opening and serves as a promising method for intravenous ocular gene delivery.

Conclusion: UTMD-mediated gene delivery system could effectively enhance gene transfer into ocular tissue. Though several problems remain to be solved, UTMD is a promising technology for the targeted gene therapy of ocular disease.

Open access

Liu Bin, Meng Zhang, Liu Lixia, Zang Aimin, Yang Hua, Shang Yanhong, Yang Yang, Gao Feng, Liu Bo, Zhang Yonggang and Tian Huiping

Abstract

Background: MiRNA-30c was a tumor suppressor in several human cancers, however, its association with clinicopathological features and prognosis in colorectal cancer (CRC) is unclear.

Materials and Methods: The expression level of miRNA-30c in 192 pairs of colorectal cancer and adjacent normal tissues was detected by Quantitative RT-PCR, the association between miRNA-30c expression and clinical characteristics and prognosis were statistically analyzed.

Results: miRNA-30c was significantly lower in CRC tissues specimens compared with matched normal adjacent tissue (P<0.001). MiRNA-30c was positively correlated with tumor size (P=0.012), TMN stage (P=0.002) and lymph node metastasis (P=0.004). The univariate analysis showed CRC patients with low miRNA-30c had distinctly shorter overall survival (P<0.001) than patients with high miRNA-30c expression level. The multivariate analysis was performed and informed that low miRNA-30c expression (P<0.001) might be an independent prognostic predictor for poor prognosis.

Conclusion: miRNA-30c could predict the prognosis of colorectal cancer which is helpful to choose reasonable treatment measures.