Fruit-Derived Extracellular-Vesicle-Engineered Structural Droplet Drugs for Enhanced Glioblastoma Chemotherapy.

Existing solid-nanoparticle-based drug delivery systems remain a great challenge for glioblastoma chemotherapy due to their poor capacities in crossing the blood-brain barrier/blood-brain tumor barrier (BBB/BBTB). Herein, fruit-derived extracellular-vesicle (EV)-engineered structural droplet drugs (ESDDs) are demonstrated by programming the self-assembly of fruit-derived EVs at the DOX@squalene-PBS interface, greatly enhancing the antitumor efficacy against glioblastoma. The ESDDs experience a flexible delivery via deformation-amplified macropinocytosis and membrane fusion, enabling them to highly efficiently cross the BBB/BBTB and deeply penetrate glioblastoma tissues. As expected, the ESDDs exhibit approximately 2.5-fold intracellular uptake, 2.2-fold transcytosis, and fivefold membrane fusion higher than cRGD-modified EVs (REs), allowing highly efficient accumulation, deep penetration, and cellular internalization into the glioblastoma tissues, and thereby significantly extending the survival time of glioblastoma mice.

Orange-derived extracellular vesicles nanodrugs for efficient treatment of ovarian cancer assisted by transcytosis effect.

Extracellular vesicles (EVs) have recently received much attention about the application of drug carriers due to their desirable properties such as nano-size, biocompatibility, and high stability. Herein, we demonstrate orange-derived extracellular vesicles (OEV) nanodrugs (DN@OEV) by modifying cRGD-targeted doxorubicin (DOX) nanoparticles (DN) onto the surface of OEV, enabling significantly enhancing tumor accumulation and penetration, thereby efficiently inhibiting the growth of ovarian cancer. The obtained DN@OEV enabled to inducement of greater transcytosis capability in ovarian cancer cells, which presented the average above 10-fold transcytosis effect compared with individual DN. It was found that DN@OEV could trigger receptor-mediated endocytosis to promote early endosome/recycling endosomes pathway for exocytosis and simultaneously reduce degradation in the early endosomes-late endosomes-lysosome pathway, thereby inducing the enhanced transcytosis. In particular, the zombie mouse model bearing orthotopic ovarian cancer further validated DN@OEV presented high accumulation and penetration in tumor tissue by the transcytosis process. Our study indicated the strategy in enhancing transcytosis has significant implications for improving the therapeutic efficacy of the drug delivery system.

Economic evaluation of methadone maintenance treatment in HIV/AIDS control among injecting drug users in Dehong, China.

The purpose of this study was to analyze the cost and cost-effectiveness of methadone maintenance treatment (MMT) program in Dehong prefecture, Yunnan province, China. The cost-effectiveness analysis used process data retrospectively collected from the MMT clinics in Dehong Prefecture, Yunnan Province, from July 2005 to December 2007, a 30-month period available at the time of the study. Alternative estimates of the number of HIV infections prevented were calculated using incidence rate from cohort studies and retrospective studies. Program costs were collected retrospectively following standard methods using an ingredients methodology. The cost for each participant treated in MMT clinics was about $9.1-16.7 per month and the intervention averted 8.4-87.2 HIV infections with a cost-effectiveness of US$ 2509.3-4609.3 per HIV infection averted. This research demonstrates that MMT is a cost-effective intervention for reducing HIV transmission among injecting drug users, but the coverage of MMT intervention should be matched with the designed volume of MMT clinics to make the best use of resources.

Lemon-Derived Extracellular Vesicles Nanodrugs Enable to Efficiently Overcome Cancer Multidrug Resistance by Endocytosis-Triggered Energy Dissipation and Energy Production Reduction.

Multidrug resistance remains a great challenge for cancer chemotherapy. Herein, a biomimetic drug delivery system based on lemon-derived extracellular vesicles (EVs) nanodrugs (marked with heparin-cRGD-EVs-doxorubicin (HRED)) is demonstrated, achieving highly efficient overcoming cancer multidrug resistance. The HRED is fabricated by modifying functional heparin-cRGD (HR) onto the surface of EVs and then by loading with doxorubicin (DOX). The obtained HRED enable to effectively enter DOX-resistant cancer cells by caveolin-mediated endocytosis (main), macropinocytosis (secondary), and clathrin-mediated endocytosis (last), exhibiting excellent cellular uptake capacity. The diversified endocytosis capacity of HRED can efficiently dissipate intracellular energy and meanwhile trigger downstream production reduction of adenosine triphosphate (ATP), leading to a significant reduction of drug efflux. Consequently, they show excellent anti-proliferation capacities to DOX-resistant ovarian cancer, ensuring the efficiently overcoming ovarian cancer multidrug resistance in vivo. The authors believe this strategy provides a new strategy by endocytosis triggered-energy dissipation and ATP production reduction to design drug delivery system for overcoming cancer multidrug resistance.

[Cost-effectiveness of female sex worker interventions by using SEX 2.0 Tool in Dehong prefecture, Yunnan province].

OBJECTIVE: To perform cost-effectiveness analysis of interventions in female sex workers in Dehong prefecture in China, with an aim of providing evidence for rational resource allocation in female sex worker interventions in the future. METHODS: The data of expenses for female sex worker interventions in Dehong from 2005 - 2007 were obtained through questionnaire survey. Meanwhile, the data from baseline survey in 2004, from surveillance of female sex workers from 2005 through 2007 as well as from the special survey on sexual transmission in 2007 were collected. Intervention effectiveness was estimated by using SEX 2.0 Tool recommended by UNAIDS. The cost-effectiveness ratio is calculated as the total cost divided by the number of estimated non-HIV patients due to these interventions. RESULTS: The total cost for female sex worker interventions is 916 400 RMB from 2005 through 2007, and a total of 3297 female sex workers were effectively intervened in these three years. Thus, the actual intervention cost for each female sex worker (unit cost) is 277.9 RMB. If all the intervention work is performed as required, the predicted unit cost for female sex worker intervention would be 500.5 RMB. During the period of 2005 through 2007, 69 female sex workers had been successfully prevented from HIV infection; therefore, the cost-effectiveness ratio is 13 282 RMB. CONCLUSION: Intervention among female sex workers is highly cost-effective.

Hydrophobicity Improvement of Cement-Based Materials Incorporated with Ionic Paraffin Emulsions (IPEs).

Cement-based materials are non-uniform porous materials that are easily permeated by harmful substances, thereby deteriorating their structural durability. In this work, three ionic paraffin emulsions (IPEs) (i.e., anionic paraffin emulsion (APE), cationic paraffin emulsion (CPE), and non-ionic paraffin emulsion (NPE), respectively) were prepared. The effects of incorporation of IPEs into cement-based materials on hydrophobicity improvement were investigated by environmental scanning electron microscopy (ESEM), Fourier transform infrared (FTIR) spectroscopy, transmission and reflection polarizing microscope (TRPM) tests and correlation analyses, as well as by compressive strength, impermeability, and apparent contact angle tests. Finally, the optimal type and the recommended dose of IPEs were suggested. Results reveal that the impermeability pressure and apparent contact angle value of cement-based materials incorporated with IPEs are significantly higher than those of the control group. Thus, the hydrophobicity of cement-based materials is significantly improved. However, IPEs adversely affect the compressive strength of cement-based materials. The apparent contact angle mainly affects impermeability. These three IPEs impart hydrophobicity to cement-based materials. In addition, the optimal NPE dose can significantly improve the hydrophobicity of cement-based materials.

Mild Oxidative Stress Reduces NRF2 SUMOylation to Promote Kras/Lkb1/Keap1 Mutant Lung Adenocarcinoma Cell Migration and Invasion.

Nuclear factor erythroid 2-related factor 2 (NRF2) is a crucial transcription factor for cell adaptation and defense against oxidative stress. NRF2 activation confers Kras/Lkb1/Keap1 (KLK) mutant tumor cells with greater resistance to oxidative insults. We previously reported that SUMOylation at lysine residue 110 is important for the ability of NRF2 to promote reactive oxygen species (ROS) clearance in hepatocellular carcinoma. In this study, we investigated whether SUMOylation is necessary for the ability of NRF2 to inhibit KLK lung adenocarcinoma (LUAD) cell migration and invasion. Our experiments showed that mild oxidative stress reduced NRF2 SUMOylation, which promoted KLK LUAD cell migration and invasion. Mechanistically, NRF2 SUMOylation increased the antioxidant ability of NRF2 and reduced cellular ROS levels, mainly by transcriptionally activating Cat in KLK LUAD cells. With reduced NRF2 SUMOylation, increased ROS acted as signaling molecules to activate the JNK/c-Jun axis, which enhanced cell mobility and cell adhesion, to promote LUAD cell migration and invasion. Taken together, the results of this study reveal a novel signaling process in which reduced NRF2 SUMOylation permits increased KLK LUAD cell migration and invasion under mild oxidative stress.

Patient-specific probabilistic atlas combining modified distance regularized level set for automatic liver segmentation in CT.

Liver segmentation from CT is regarded as a prerequisite for computer-assisted clinical applications. However, automatic liver segmentation technology still faces challenges due to the variable shapes and low contrast. In this paper, a patient-specific probabilistic atlas (PA)-based method combing modified distance regularized level set for liver segmentation is proposed. Firstly, the similarities between training atlases and testing patient image are calculated, resulting in a series of weighted atlas, which are used to generate the patient-specific PA. Then, a most likely liver region (MLLR) can be determined based on the patient-specific PA. Finally, the refinement is performed by the modified distance regularized level set model, which takes advantage of both edge and region information as balloon force. We evaluated our proposed scheme based on 35 public datasets, and experimental result shows that the proposed method can be deployed for robust and precise liver segmentation, to replace the tedious and time-consuming manual method.

Aging Characteristics of Bitumen from Different Bituminous Pavement Structures in Service.

The aging of bitumen seriously affects the service life of bituminous pavements. At present, there are many related researches on bitumen aging, but most of them focus on aging endured in indoor surroundings and conditions. Therefore, the conclusions obtained cannot reflect the actual aging changes of bitumen in bituminous pavements in service. In order to study the comprehensive aging process and mechanism of bitumen under the influence of service, we studied bridge deck, traffic lane, and ramp with bituminous pavement structures in service. The bitumen samples obtained from the core samples in different bituminous pavement structures were characterized by gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), dynamic shear rheometer (DSR), and fluorescence microscope (FM). The aging degree of different bitumen was analyzed, and conclusions were drawn on changes to bitumen aging from different pavement structures. The results showed that the aging degree of bitumen from the upper layer was the most serious, the aging degree of bitumen at the middle layer was weaker than that of bitumen from the upper layer, and the aging degree of bitumen from the bottom layer was the weakest for the different bituminous pavement structures. The aging of bitumen mainly occurred due to oxygen absorption. After aging, viscoelastic components of bitumen changed, and bitumen became harder. The macromolecule of bitumen could be divided into small molecules, and the small molecular weight of bitumen became large. The styrene-butadiene-styrene (SBS) modifier in the modified bitumen became granular after aging, and it appeared as a single phase in bitumen. The aging changes characterized by different analytical methods showed that the aging degree of bitumen from different layers of bituminous pavement structures in service was different. Effective measures should therefore be taken in time to decrease further aging of bitumen from the upper layer of bituminous pavements due to its inevitable early aging in service.

NRF2 SUMOylation promotes de novo serine synthesis and maintains HCC tumorigenesis.

Nuclear factor erythroid-2 related factor 2 (NRF2) is a pivotal transcription factor that maintains cellular redox homeostasis and facilitates the development of malignant tumor phenotypes. At the molecular level, NRF2 promotes de novo serine synthesis and SUMOylation affects its function. Our results indicated that the SUMO1 acceptor site of NRF2 is the conserved lysine residue 110 (K110), and that NRF2 SUMOylation deficiency inhibited tumorigenesis in hepatocellular carcinoma (HCC). Mechanistically, NRF2 SUMOylation promoted de novo serine synthesis in HCC by enhancing the clearance of intracellular reactive oxygen species (ROS) and up-regulating phosphoglycerate dehydrogenase (PHGDH). More importantly, serine starvation increased the level of NRF2 SUMOylation, leading to sustained HCC growth. Collectively, our results indicate the presence of a novel NRF2 SUMOylation-mediated signaling process that maintains HCC tumorigenesis in normal conditions and in response to metabolic stress.

[Resource allocation analysis for international cooperation program for HIV/AIDS prevention and control].

OBJECTIVE: To provide evidence for resource allocation and cooperation between domestic and international HIV/AIDS programs in China by analyzing the needs and current levels of resource input in provinces. METHODS: National and provincial international cooperation program investment and allocation data from 2000 to 2006 were collected. Several factors in each province were analyzed through multiple regression analysis in order to determine whether they had a statistical correlation to the distribution of international HIV/AIDS program resources in China, including: the Gross Domestic Product (GDP), the number of accumulated people living with HIV/AIDS, and the number of accumulated people living with AIDS. Then the Z values were calculated at each provincial level and compared with related international investment. The resource allocation in different program areas were compared with the level of resource input by international and central government HIV/AIDS prevention and control programs through Chi-square test. RESULTS: The international cooperation program investment at local level from 2000 to 2006 were 4893, 24 669, 50 567, 52 950, 112 143, 363 396 and 247 045 thousand RMB respectively, and at national level were 3007, 19 726, 29 035, 37 530, 77 500, 105 786 and 77 035 thousand RMB respectively. There was a statistical correlation between international HIV/AIDS program resource input and the accumulated number of people living with AIDS (R is 0.56 and 0.69 accordingly, and P < 0.01 both). However, there was no statistical correlation between international resource input and the GDP of each province. International HIV/AIDS cooperation programs did not invest in each province according to its practical needs (R = 0.066, P = 0.725). The international cooperation program investments and needs in different province could not meet completely. The ranks of Z value in Guangdong, Shandong and Jiangsu were 3, 5 and 6, but the ranks of international cooperation program in those provinces were 18, 13 and 28 respectively. The investment proportion for national investment in surveillance and testing, advocacy education and intervention, care and support, and others were 22.4%, 19.7%, 36.8% and 21.1% respectively in 2005, and for international cooperation program were 11.5%, 20.8%, 10.4% and 57.4%. For national investment in 2006 were 18.6%, 23.8%, 32.6% and 25.0%, and international cooperation program were 14.0%, 34.3%, 17.1% and 34.6% respectively. The Chinese government and international programs therefore had different priorities in 2005 (chi(2) = 35.09, P < 0.01) and 2006 (chi(2) = 9.26, P = 0.026). CONCLUSIONS: International HIV/AIDS cooperation programs should be better integrated with national programs and combined with epidemic situation and GDP to decide the amount and areas of the investment in order to ensure that they supplement Chinese HIV/AIDS prevention and control activities effectively. The advantages that can be gained from technical support provided by international programs should be further emphasized in line with China's HIV/AIDS prevention and control priorities.

[Analysis of the epidemiologic patterns of HIV transmission in Dehong prefecture, Yunnan province].

OBJECTIVE: To uncover the transmission patterns of the HIV epidemic in Dehong prefecture. METHODS: The reviewed case reports, data of sentinel surveillance, testing and special survey were analyzed by SAS 8.0 program. The transmission patterns were modeled by utilizing data including sizes of the whole population and the high risk groups, high risk behavior data from 1989 to 2007, and the population index such as sex ratio and fertility rate. RESULTS: In 2005, case reports showed the proportion of people infected with HIV through sexual contact was 39.1%, and 46.9% in 2006. Among 1636 cases reported between January 1 to September 20, 2007, the proportion of people infected with HIV through sexual contact was 52%. From 1989 to 2007, the proportion of HIV infection among drug users was declining, while HIV infection through sexual contact was rising after standardizing the population tested/surveyed. The Asian Epidemic Model has shown that the proportions of incident HIV infections through sexual transmissions were 50.6%, 52.3% and 52.7% respectively from 2005 to 2007. Correspondingly, the proportions of incident cases by injecting drug user were 48.9%, 47.2% and 46.7% respectively during this period. Moreover, the Workbook method has shown that, among adults living with HIV in 2007, 50.3% were infected through injecting drugs and 48.4% through unsafe sexual activity. CONCLUSION: The rapid rise in HIV infections through injecting drug in Dehong prefecture has been initially curbed. HIV epidemic has already witnessed a change from predominantly through drug injecting-related activity to an almost equally fuelled epidemic by sexual and drug-related transmission.

[Current situation and influential factors concerning the sexual transmission of HIV in Dehong prefecture, Yunnan province].

OBJECTIVE: To investigate the current situation of the sexual transmission of HIV in Dehong prefecture, analyze the influential factors, and provide support for drafting pertinent preventive interventions in the future. METHODS: We had analyzed the data of case report from 2005 to 2007, and the prostitutes surveillance data from 2003 to 2007. A special survey was conducted from October 26 to November 7, 2007. Totally 685 people including prostitutes, the clients of prostitutes, people who were HIV positive and their partners, key insiders were interviewed in order to better understand the influential factors related to sexual transmission of HIV. RESULTS: Among 1636 cases reported from January 1 to September 20, 2007, 52% were infected through sexual transmission. Among 586 cases infected through sexual transmission, 40.6% had commercial sexual behavior and 28.6% had unmarried sexual behavior. And the average rate of condom use was below 30%. The prostitutes' surveillance data from 2003 to 2007 showed that the HIV positive rate in prostitutes was 3.3% - 5.5%. The rate of condom use in the last month was 29.4% - 84.4% during commercial sexual activity, but it was 9.5% - 34.8% with fixed sexual partners. Although the rate of HIV and AIDS-related knowledge among prostitutes was 95.0%, there were still many misunderstanding regarding certain aspects of HIV and AIDS awareness. CONCLUSION: Sexual transmission has become one of the main transmission routes of HIV in Dehong prefecture. The main factors involved in the sexual transmission of HIV in Dehong prefecture might include the wide spreading of sexual services, cohabitation among unmarried couples, having multiple partners, casual sexual behavior, and the low rate of condom use.

3D surface voxel tracing corrector for accurate bone segmentation.

PURPOSE: For extremely close bones, their boundaries are weak and diffused due to strong interaction between adjacent surfaces. These factors prevent the accurate segmentation of bone structure. To alleviate these difficulties, we propose an automatic method for accurate bone segmentation. The method is based on a consideration of the 3D surface normal direction, which is used to detect the bone boundary in 3D CT images. METHODS: Our segmentation method is divided into three main stages. Firstly, we consider a surface tracing corrector combined with Gaussian standard deviation [Formula: see text] to improve the estimation of normal direction. Secondly, we determine an optimal value of [Formula: see text] for each surface point during this normal direction correction. Thirdly, we construct the 1D signal and refining the rough boundary along the corrected normal direction. The value of [Formula: see text] is used in the first directional derivative of the Gaussian to refine the location of the edge point along accurate normal direction. Because the normal direction is corrected and the value of [Formula: see text] is optimized, our method is robust to noise images and narrow joint space caused by joint degeneration. RESULTS: We applied our method to 15 wrists and 50 hip joints for evaluation. In the wrist segmentation, Dice overlap coefficient (DOC) of [Formula: see text]% was obtained by our method. In the hip segmentation, fivefold cross-validations were performed for two state-of-the-art methods. Forty hip joints were used for training in two state-of-the-art methods, 10 hip joints were used for testing and performing comparisons. The DOCs of [Formula: see text], [Formula: see text]%, and [Formula: see text]% were achieved by our method for the pelvis, the left femoral head and the right femoral head, respectively. CONCLUSION: Our method was shown to improve segmentation accuracy for several specific challenging cases. The results demonstrate that our approach achieved a superior accuracy over two state-of-the-art methods.

Automatic Approach for Lung Segmentation with Juxta-Pleural Nodules from Thoracic CT Based on Contour Tracing and Correction.

This paper presents a fully automatic framework for lung segmentation, in which juxta-pleural nodule problem is brought into strong focus. The proposed scheme consists of three phases: skin boundary detection, rough segmentation of lung contour, and pulmonary parenchyma refinement. Firstly, chest skin boundary is extracted through image aligning, morphology operation, and connective region analysis. Secondly, diagonal-based border tracing is implemented for lung contour segmentation, with maximum cost path algorithm used for separating the left and right lungs. Finally, by arc-based border smoothing and concave-based border correction, the refined pulmonary parenchyma is obtained. The proposed scheme is evaluated on 45 volumes of chest scans, with volume difference (VD) 11.15 ± 69.63 cm3, volume overlap error (VOE) 3.5057 ± 1.3719%, average surface distance (ASD) 0.7917 ± 0.2741 mm, root mean square distance (RMSD) 1.6957 ± 0.6568 mm, maximum symmetric absolute surface distance (MSD) 21.3430 ± 8.1743 mm, and average time-cost 2 seconds per image. The preliminary results on accuracy and complexity prove that our scheme is a promising tool for lung segmentation with juxta-pleural nodules.

The impact of comprehensive prevention of mother-to-child HIV transmission in Dehong prefecture, Yunnan province, 2005-2010: a hard-hit area by HIV in Southern China.

The burden of HIV/AIDS in China has been disproportionately concentrated in Yunnan Province, where in Dehong prefecture, the HIV prevalence rate among pregnant women reached 1.3% in 2003, a rate that is indicative of a generalized epidemic. Since then, there have been extensive efforts to expand prevention to reduce mother-to-child transmission (MTCT) in this high-prevalence region. These intensified MTCT reduction efforts and their impact on MTCT are yet to be examined. We described the changes in access to HIV screening and antiretroviral therapy (ART) among pregnant women from 2005 to 2010 in this region and the corresponding reduction in MTCT over this period. Between 2005 and 2010, the annual number of pregnant women screened for HIV in Dehong Prefecture more than doubled. The proportion of pregnant women screened for HIV rose from an estimated 15-20% to 99.8%, and the proportion of HIV-infected pregnant women receiving ART increased from 63% to 99%. We estimate that the proportion of children born with HIV to HIV-infected mothers decreased from 15.4% to 7.2% over this period. Sustained low-level MTCT following comprehensive interventions in this region is encouraging. Over the last decade, comprehensive PMTCT efforts, coupled with national and local government policy support in this area appear to be effective.

Contributions of international cooperation projects to the HIV/AIDS response in China.

BACKGROUND: For 20 years, China has participated in 267 international cooperation projects against the HIV/AIDS epidemic and received ∼526 million USD from over 40 international organizations. These projects have played an important role by complementing national efforts in the fight against HIV/AIDS in China. METHODS: The diverse characteristics of these projects followed three phases over 20 years. Initially, stand-alone projects provided technical support in surveillance, training or advocacy for public awareness. As the epidemic spread across China, projects became a part of the comprehensive and integrated national response. Currently, international best practices encourage the inclusion of civil society and non-governmental organizations in an expanded response to the epidemic. RESULTS: Funding from international projects has accounted for one-third of the resources provided for the HIV/AIDS response in China. Beyond this strong financial support, these programmes have introduced best practices, accelerated the introduction of AIDS policies, strengthened capacity, improved the development of grassroots social organizations and established a platform for communication and experience sharing with the international community. However, there are still challenges ahead, including integrating existing resources and exploring new programme models. The National Centre for AIDS/STD Control and Prevention (NCAIDS) in China is consolidating all international projects into national HIV prevention, treatment and care activities. CONCLUSION: International cooperation projects have been an invaluable component of China's response to HIV/AIDS, and China has now been able to take this information and share its experiences with other countries with the help of these same international programmes.

From spectators to implementers: civil society organizations involved in AIDS programmes in China.

BACKGROUND: Over the past 20 years, civil society organizations (CSOs) in China have significantly increased their involvement in the AIDS response. This article aims to review the extent of civil society participation in China AIDS programmes over the past two decades. METHODS: A desk review was conducted to collect Chinese government policies, project documents and published articles on civil society participation of HIV/AIDS programmes in China over the past two decades. Assessment focused on five aspects: (i) the political environment; (ii) access to financial resources; (iii) the number of CSOs working on HIV/AIDS; (iv) the scope of work; and (v) the impact of CSO involvement on programmes. RESULTS: The number of CSOs specificly working on HIV/AIDS increased from 0 before 1988 to over 400 in 2009. Among a sample of 368 CSOs, 135 (36.7%) were registered. CSOs were primarily supported by international programmes. Government financial support to CSOs has increased from USD248 000 in 2002 to USD1.46 million in 2008. Initially, civil society played a minimal role. It is now widely involved in nearly all aspects of HIV/AIDS-related prevention, treatment and care efforts, and has had a positive impact; for example, increased adherence of anti-retroviral treatment and HIV testing among hard-to-reach groups. The main challenges faced by CSOs include registration, capacity and long-term financial support. CONCLUSION: CSOs have significantly increased their participation and contribution to HIV/AIDS programmes in China. Policies for registration and financial support to CSOs need to be developed to enable them to play an even greater role in AIDS programmes.

[Dissemination of insertion sequences IS605, IS606 among clinical isolates of Helicobacter pylori in China].

OBJECTIVE: To study the distribution of IS605, IS606 among clinical isolates of Helicobacter pylori in China. METHODS: A total of 104 H.pylori strains isolated from 5 different geographic regions in China were analyzed by PCR and dot-blot. RESULTS: Forty-two strains out of the 104 isolates from 5 regions in China were found containing IS605 with 19 containing IS606. The frequency (66%) of IS605 positive strains from Yunnan province was higher than that from other areas. The different distribution of IS606 was neither associated with geographical regions nor with the presence of IS605 but IS606 were associated with the different clinical outcomes. However, the two reading frames ORFA and ORFB of IS605 were constantly coexisting. CONCLUSION: In China, IS605 and IS606 of H. pylori were widely existing but the presence of IS605 in H. pylori might be associated with geographic origin.