Advances in the use of nanomaterials for nucleic acid detection in point-of-care testing devices: A review.

The outbreak of the coronavirus (COVID-19) has heightened awareness of the importance of quick and easy testing. The convenience, speed, and timely results from point-of-care testing (POCT) in all vitro diagnostic devices has drawn the strong interest of researchers. However, there are still many challenges in the development of POCT devices, such as the pretreatment of samples, detection sensitivity, specificity, and so on. It is anticipated that the unique properties of nanomaterials, e.g., their magnetic, optical, thermal, and electrically conductive features, will address the deficiencies that currently exist in POCT devices. In this review, we mainly analyze the work processes of POCT devices, especially in nucleic acid detection, and summarize how novel nanomaterials used in various aspects of POCT products can improve performance, with the ultimate aims of offering new ideas for the application of nanomaterials and the overall development of POCT devices.

Effects of growth hormone/estrogen/androgen on COVID-19-type proinflammatory responses in normal human lung epithelial BEAS-2B cells.

BACKGROUND: COVID-19 is a disease caused by SARS-CoV-2, which can cause mild to serious infections in humans. We aimed to explore the effect of growth hormone (GH)/estrogen/androgen in normal human lung epithelial BEAS-2B cells on COVID-19-type proinflammatory responses. METHODS: A BEAS-2B COVID-19-like proinflammatory cell model was constructed. After that, the cells were treated with GH, 17ß-estradiol (E2), and testosterone (Tes) for 24 h. CCK-8 assays were utilized to evaluate cell viability. The mRNA expression of ACE2, AGTR1, TMRRSS2, and ISG15 and the protein expression of ACE2, AGTR1, TMRRSS2, and ISG15 were measured by qRT‒PCR and Western blotting, respectively. ELISAs were performed to determine IL-6, MCP-1, MDA and SOD expression. Flow cytometry was used to measure ROS levels. Finally, MAPK/NF-κB pathway-related factor expression was evaluated. RESULTS: The COVID-19-type proinflammatory model was successfully constructed, and 1000 ng/mL RBD treatment for 24 h was selected as the condition for the model group for subsequent experiments. After RBD treatment, cell viability decreased, the mRNA expression of ACE2, AGTR1, TMRRSS2, and ISG15 and the protein expression of ACE2, AGTR1, TMRRSS2, and ISG15 increased, IL-6, MCP-1, MDA and ROS levels increased, and MDA levels decreased. The mRNA levels of MAPK14 and RELA increased, but the protein levels did not change significantly. In addition, phospho-MAPK14 and phospho-RELA protein levels were also increased. Among the tested molecules, E2 had the most pronounced effect, followed by GH, while Tes showed the opposite effect. CONCLUSION: GH/E2 alleviated inflammation in a COVID-19-type proinflammatory model, but Tes showed the opposite effect.

HPLC assay of epinephrine sulfonate in epinephrine injection / 药学学报

An HPLC method was established for the assay of epinephrine sulfonate (impurity F) in epinephrine injection. The determination was performed on an AQUASIL C18 (100 mm × 4.6 mm, 3 μm) column with a gradient elution system, and the mobile phase was consisted of monopotassium phosphate solution (mobile phase A) and acetonitrile (mobile phase B). The injection volume was 40 μL. The detection wavelength was at 210 nm and the column temperature was 25 ℃. The total analytical time was 40 min. The results showed that the standard cure of epinephrine sulfonate (impurity F) between peak area and concentration exhibited good linear relationship within the ranges of 0.520-12.480 μg·mL-1 and the R2 = 0.999 8. The average recovery rate was 103.04% and the RSD was 2.00%. The limit concentration of detection was 0.104 μg·mL-1 and the limit concentration of quantitation was 0.520 μg·mL-1. The method could be applied to the determination of epinephrine sulfonate in epinephrine injection with high accuracy and precision, as well as good sensitivity. It could also enhance the quality standards of epinephrine-related products.

Characterization of ferroptosis signature to evaluate the predict prognosis and immunotherapy in glioblastoma.

BACKGROUND: Glioblastoma (GBM) is the most common type of brain cancer with poor survival outcomes and unsatisfactory response to current therapeutic strategies. Recent studies have demonstrated that ferroptosis-related genes (FRGs) are linked with the occurrence and development of GBM and may become promising biological indicators in GBM therapy. METHODS: We systematically assessed the relationship between FRGs expression profiles and prognosis in glioma patients based on the Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) datasets to establish a risk score model according to the gene signature of multiple survival-associated DEGs. Further, the differences between the tumor microenvironment score, immune cell infiltration, immune checkpoint expression levels, and drug sensitivity in the high- and low-risk group are analyzed through a variety of algorithms in R software. RESULTS: GBM patients were divided into two subgroups (high- and low-risk) according to the established risk score model. Patients in the high-risk group showed significantly reduced overall survival compared with those in the low-risk group. Also, we found that the high-risk group showed higher ImmuneScore and StromalScore, while different subgroups have significant differences in immune cell infiltration, immune checkpoint expression levels, and drug sensitivity. In summary, we developed and validated an FRGs risk model, which served as an independent prognostic indicator for GBM. Besides, the two subgroups divided by the model have significant differences, which provides novel insights for further studies as well as the personalized treatment of patients.

LncRNA GAS5 regulates epithelial-mesenchymal transition and viability of glioma cells by targeting microRNA-106b and regulating PTEN expression.

LncRNA growth arrest special 5 (GAS5) and microRNA-106b (miR-106b) have been reported to be involved in the regulation of gliomas. However, their precise mechanisms in regulating the progression and development of gliomas remain unclear. We aimed to investigate the interaction between GAS5 and miR-106b, and their influence on the proliferation, migration, and invasion of gliomas cells. Western blotting and qRT-PCR were applied for measuring expression of protein and mRNA, respectively. The proliferation, migration, and invasion of cells were measured by MTT, wound healing, and transwell assays, respectively. Dual luciferase reporter assay was applied for confirming the binding site between miR-106b and GAS5, miR-106b and PTEN. Significant higher expression of miR-106b, and lower expression of GAS5 and PTEN in the glioma tissues were observed. The binding sites between GAS5 and miR-106b, miR-106b and PTEN were identified. GAS5 could regulate the expression of PTEN through targeting miR-106b, and further influence EMT process, and the proliferation, migration, and invasion of gliomas cells. Meanwhile, PTEN could remarkably inhibited the proliferation, migration and invasion of glioma cells. The influence of PTEN on glioma cells and EMT was similar to GAS5. GAS5 could regulate the EMT process, and the migration of gliomas cells through miR-106b targeting PTEN. Therefore, our findings may provide a new thought for the study of pathogenesis and treatment of glioma.

The effect of hypoxia on the proliferation capacity of dermal papilla cell by regulating lactate dehydrogenase.

Hypoxia is of great significance for stem cells to maintain the proliferation and differentiation capacity. As a specialized mesenchymal component of the hair follicle (HF), the dermal papilla cell (DPC) not only regulates HF cycle, but also plays a pivotal role in differentiating hair follicle stem cell(HFSC) into HF. However, whether hypoxia could affect DPCs on proliferation or metabolism remains unclear. In our study, DPCs were cultured in normoxia (20%O2 ) or hypoxia (5%O2 ). Cell viability assays were performed, and lactate dehydrogenase (LDH) activity and lactate level in DPCs were detected. After that, LDH was overexpressed or knocked down in DPCs; then, the expression of protein markers (ALP, Ki-67) was assessed by Western blotting, and cell proliferation was also detected after overexpression or knockdown of LDH. Hypoxia did show positive effect on proliferation of DPCs. The LDH activity of DPCs cultured under hypoxic condition was significantly higher than that of cultured under normoxic condition. Overexpression of LDH significantly up-regulates the expression of ALP and Ki-67 compared with knockdown and negative control. Cell proliferation was also promoted in DPCs with elevated LDH. Our findings showed that the proliferation activity of DPCs could be stimulated under hypoxia. Meanwhile, LDH plays an important role in maintaining the activity of DPCs in hypoxic condition.

Application of photoacoustic imaging in the diagnosis and treatment of skin tumors / 中华皮肤科杂志

Photoacoustic imaging is a kind of non-invasive technology without ionizing radiation that can be used to image optical absorbers in tumor tissues according to the principle of "light in and sound out". It has the advantages of high contrast of optical imaging as well as high penetrability of acoustic imaging. However, current researches on photoacoustic imaging are still limited in the laboratory. This technology can be used for detection of cutaneous melanoma in situ and non-melanoma skin cancer, sentinel lymph node imaging, detection and eradication of circulating tumor cells by combining real-time laser ablation technique, and versatile imaging and treatment with the aid of exogenous imaging agents. This review summarizes preclinical experiments about photoacoustic imaging technology in skin tumors, with a view to promoting its clinical application at an early date.

Novel Detection of Norovirus and Double Clostridium difficile in a Closed Cartridge System.

Clostridium difficile infection (CDI) has become the main cause of diarrhea-related diseases in domestic (China) inpatients. High-sensitivity and high-specificity detection methods for CDI must be applied clinically for CDI supervisory control. In this paper, we introduce a detection method for C. difficile and Norovirus based on real-time PCR. We developed and optimized a primer-probe for Norovirus targets tcdA and tcdB with remarkably increased detection sensitivity. We then used this method in an integrated cassette, and found increased detection efficiency for Norovirus standards in the cassette compared to C. difficile samples. These results provide a basis for further exploration of automatic testing system design.

Carotid artery calcification score and its association with cognitive impairment.

PURPOSE: To retrospectively investigate the possible association between carotid artery calcification score (CS) and cognitive impairment in carotid artery stenosis (CAS) patients. PATIENTS AND METHODS: Carotid artery was measured in 102 patients with cervical carotid arteries using Color Doppler ultrasound, multi-detector row spiral CT angiography and MRI scanning. Correlation analysis between CSs obtained by MD CT and cognitive scores was performed, and the correlation between CSs and vascular stenosis degree and MRI-measured plaque histological (lipid-rich necrotic nucleus [LRNC], intraplaque hemorrhage and fibrous cap surface rupture) and morphological parameters (lumen area [LA], wall area [WA], total area of blood vessels [TVA], plaque burden [PB]) was analyzed. Follow-up review analysis was conducted on 38 postoperative patients. RESULTS: Significant negative correlation was discovered between CS value and cognitive scores in CAS patients (R=-0.359, P<0.001), which did not exist in postoperative patients (P=0.348); CS value also showed significant correlation with WA (R=0.521, P=0.042), TVA (R=0.215, P=0.017) and PB (R=0.237, P=0.003) and had a certain predictive value for the occurrence probability of carotid plaque LRNC (P=0.029, AUC =0.780) in preoperative patients. CONCLUSION: Carotid artery CSs have significant correlation with cognitive scores, which could be used as risk factor for early screening of cognitive impairment in CAS patients. The possible mechanism may be related to the calcification impact on the plaque burden.

Changes of proportion regarding consistent condom use and syphilis infection among low-fee female sex workers aged 35 and above / 中华流行病学杂志

Objective To investigate the changes of proportion on both consistent condom use and syphilis infection among low-fee female sex workers aged 35 and above (LFSW),in order to provide evidence for targeted intervention strategies.Methods A total of six cities-Liuzhou city and Pingnan couty of Guigang city of Guangxi Zhuang Autonomous Region,Jinghong city of Xishuangbanna Dai autonomous prefecture and Dali city of Dali Bai autonomous prefecture of Yunnan province,Zhangjiajie city and Jianghua Yao autonomous county of Yongzhou city Hunan province were involved in this study,with 60 eligible participants needed in each city,estimated through a pre-study.The first cross-sectional survey was completed from October 2012 to January 2013.Face-to-face questionnaire interview was carried out to collect information on socio-demography,work-related information and condom use situation.Blood was collected for syphilis testing.The second cross-sectional survey was carried out from June to September,2015 under the same procedure.Results A total of 371 and 403 eligible participants were included in the first and second survey,respectively.When comparing the two surveys,we noticed that the average age showed a slight change,from 42.4 years to 43.8 years old (t=3.537,P＜0.001) and the average price for every commercial sex exchange increased from 36.8 RMB to 49.5 RMB (t=11.961,P＜0.001).In the first survey,46.9％ (174/371) of the participants had more than two years of experience working as LFSW,compared to 61.3％ (247/403) in the second survcy (x2=16.125,P＜0.001).Also,46.9％ (174/371) of the participants consistently used condoms with clients in the past month in the first survey versus 64.3％ (259/403) (x2=23.641,P＜0.001) in the second one.Rates of syphilis infection were found from 15.9％ (59/371) in the first survey reduced to 7.2％ (29/403) in the second survey (x2=14.533,P＜0.001).Conclusion Compared with the first survey,the proportion of consistent condoms use showed an increase.Although the proportion of syphilis infection decreased in the second survey,the scope did not meet the criteria on syphilis,set by the government.Targeted intervention strategies on condom promotion and syphilis control should be implemented consistently in this population.

Changes of proportion regarding consistent condom use and syphilis infection among low-fee female sex workers aged 35 and above / 中华流行病学杂志

Objective To investigate the changes of proportion on both consistent condom use and syphilis infection among low-fee female sex workers aged 35 and above (LFSW),in order to provide evidence for targeted intervention strategies.Methods A total of six cities-Liuzhou city and Pingnan couty of Guigang city of Guangxi Zhuang Autonomous Region,Jinghong city of Xishuangbanna Dai autonomous prefecture and Dali city of Dali Bai autonomous prefecture of Yunnan province,Zhangjiajie city and Jianghua Yao autonomous county of Yongzhou city Hunan province were involved in this study,with 60 eligible participants needed in each city,estimated through a pre-study.The first cross-sectional survey was completed from October 2012 to January 2013.Face-to-face questionnaire interview was carried out to collect information on socio-demography,work-related information and condom use situation.Blood was collected for syphilis testing.The second cross-sectional survey was carried out from June to September,2015 under the same procedure.Results A total of 371 and 403 eligible participants were included in the first and second survey,respectively.When comparing the two surveys,we noticed that the average age showed a slight change,from 42.4 years to 43.8 years old (t=3.537,P＜0.001) and the average price for every commercial sex exchange increased from 36.8 RMB to 49.5 RMB (t=11.961,P＜0.001).In the first survey,46.9％ (174/371) of the participants had more than two years of experience working as LFSW,compared to 61.3％ (247/403) in the second survcy (x2=16.125,P＜0.001).Also,46.9％ (174/371) of the participants consistently used condoms with clients in the past month in the first survey versus 64.3％ (259/403) (x2=23.641,P＜0.001) in the second one.Rates of syphilis infection were found from 15.9％ (59/371) in the first survey reduced to 7.2％ (29/403) in the second survey (x2=14.533,P＜0.001).Conclusion Compared with the first survey,the proportion of consistent condoms use showed an increase.Although the proportion of syphilis infection decreased in the second survey,the scope did not meet the criteria on syphilis,set by the government.Targeted intervention strategies on condom promotion and syphilis control should be implemented consistently in this population.

HIV and syphilis infection and related medical treatment status of low-fee female sex workers in three provinces of China, 2012-2015 / 中华预防医学杂志

Objective@#To understand the HIV and syphilis infection and related treatment status of low-fee female sex workers (FSWs) in 3 provinces of China.@*Methods@#Four cross-sectional survey data of low-fee FSWs from six cities (counties) in Guangxi, Yunnan and Hunan Province between October 2012 and July 2015 were obtained from the national science and technology major special project intervention study for reducing sexually transmitted diseases (STDs) and acquired immunodeficiency syndrome (AIDS) in low-fee FSWs' database, which included social demographic characteristics, sexual service characteristics and related medical care seeking behaviors, etc. A total of 2 050 subjects were included in the database.@*Results@#The age of the subjects was (35.16±9.76) years old, with a minimum age of 15 and a maximum age of 67. Those who use condoms every time in commercial sex accounted for 58.9% (n=1 206). Among the reasons of not using condom, the proportion of client reluctant to use was the highest (81.0% (n=682)). Only 38.1% (n=782) was tested for HIV in the last six months. HIV confirmed positive rate was 6.8% (n=139), previous positive accounts for 76.3% (n=106). Rate of antiviral therapy was 55.4% (n=77). By the end of 2015, the loss rate of antivirus treatment was 18.2% (n=14). Those who self-reported symptoms of sexually transmitted diseases in the last 6 months accounted for 9.4% (n=191). 50.3% (n=96) of reporters chose to go to formal hospitals, 23.0% (n=44) chose to go to private clinics and 20.4% (n=39) chose their own medication. The syphilis infection rate was 13.5% (n=277), among them, 91.3% (n=253) were asymptomatic.@*Conclusion@#Among low-fee FSWs, the rates of HIV and syphilis infection are higher, the condom consistent use rate, HIV antibodies and syphilis test rate are lower. In this group, active seeking medical idea is poor, the rate of anti-virus treatment and the rate of seeking medical treatment in formal medical institutions is low.

Symmetrical Hierarchical Stochastic Searching on the Line in Informative and Deceptive Environments.

A stochastic point location (SPL) problem aims to find a target parameter on a 1-D line by operating a controlled random walk and receiving information from a stochastic environment (SE). If the target parameter changes randomly, we call the parameter dynamic; otherwise static. SE can be 1) informative (p > 0.5 where p represents the probability for an environment providing a correct suggestion) and 2) deceptive (p <; 0.5). Up till now, hierarchical stochastic searching on the line (HSSL) is the most efficient algorithms to catch static or dynamic parameter in an informative environment, but unable to locate the target parameter in a deceptive environment and to recognize an environment's type (informative or deceptive). This paper presents a novel solution, named symmetrical HSSL, by extending an HSSL binary tree-based search structure to a symmetrical form. By means of this innovative way, the proposed learning mechanism is able to converge to a static or dynamic target parameter in the range of not only 0.6181 <; p <; 1, but also 0 <; p <; 0.382. Finally, the experimental results show that our scheme is efficient and feasible to solve the SPL problem in any SE.

Protective effects of Dahuang Zhechong Pills on mice with alcohol-induced liver fibrosis / 中成药

AIM To investigate the protective effects of Dahuang Zhechong (DHZC) Pills (Rhei Radix et Rhizoma,Eupolyphaga seu Steleophaga,Hirudo,etc.) against alcoholic liver fibrosis (ALF) injury in mice and to explore the underlying mechanisms.METHODS C57BL/6 male mice were used to build up ALF injury model,intervened with DHZC Pills.The serum of mice was examined for changes in alanine transaminase (ALT),aspartate aminotransferase (AST),interleukin-6 (IL-6),interleukin-10 (IL-10),interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α).Simultaneously,the deposit of collagen 1 (COL-1) and apoptotic cell death in liver tissues were analyzed by immunofluorescent and TUNEL assay,respectively.The expressions of cleaved caspase-3 (CC3) in livers were measured by Western blot.RESULTS Compared with the model group,the levels of serum ALT,AST,IL-6,IFN-γand TNF-α of mice in DHZC group were decreased significantly.And the level of serum IL-10 of mice in DHZC group was increased significantly.Mice in DHZC group had higher rates of COL-1 deposition and apoptotic cell death in liver tissues than those in the model group.Mice treated with DHZC Pills showed lower expression of CC3.CONCLUSION DHZC Pills confers protection against ALF injury in mice by inhibiting the generation of COL-1 and down-regulating apoptosis of liver cells death as a result of adjusting the levels of inflammatory factors.

Mineral and Bone Disorder and Its Association with Cardiovascular Parameters in Chinese Patients with Chronic Kidney Disease / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Mineral and bone disorder (MBD), especially hyperphosphatemia, is an independently risk factor for adverse prognosis in patients with chronic kidney disease (CKD). However, CKD-MBD among Chinese population was poorly studied. This study aimed to investigate the status of MBD and its association with cardiovascular parameters in Chinese patients with predialysis CKD.</p><p><b>METHODS</b>Chinese Cohort Study of Chronic Kidney Disease (C-STRIDE) is a prospective multicenter cohort study involving predialysis CKD patients in China. Markers of MBD, including serum phosphorus, calcium, and intact parathyroid hormone, were measured in baseline samples at the patients' entry. The association between serum phosphorus and abdominal aortic calcification (AAC), left ventricular hypertrophy (LVH) were examined by logistic regression models.</p><p><b>RESULTS</b>Altogether 3194 predialysis patients with mean estimated glomerular filtration of 51.8 ± 33.1 ml.min-1.1.73 m-2 were included. The proportion of patients with hyperphosphatemia were 2.6%, 2.9%, 6.8%, and 27.1% in CKD Stages 3a, 3b, 4, and 5, respectively. Moreover, 71.6% of the patients with hyperphosphatemia did not receive any phosphate-binder (PB). Lateral abdominal X-rays were obtained in 2280 patients, 9.8% of the patients were diagnosed as having AAC. Altogether 2219 patients had data of echocardiography, and 13.2% of them were diagnosed with LVH. Multivariate logistic regression analysis showed that serum phosphorus was independently associated with the presence of AAC and LVH.</p><p><b>CONCLUSIONS</b>In Chinese patients with CKD, the percentage of hyperphosphatemia is comparable to that of other countries while the usage of PBs is suboptimal. The prevalence of vascular calcification in Chinese patients is relatively lower compared with the Caucasian population.</p>

Implementation of intervention programs on AIDS-related sexual transmission in China / 中华流行病学杂志

Objective To analyze the implementation of intervention programs targeted on AIDS high risk sexual transmission groups since 2008,when the relative prevention and control information systems on HIV/AIDS were developed.Methods Data from both aggregated interventions and sentinel surveillance programs from 2008 to the end of 2014 were used.Descriptive statistics were performed to analyze the trends of implementation on high risk groups including men who have sex with men,female sex workers (FSW) and migrant workers.Results From 2008 to 2012,the monthly average numbers receiving intervention programs and the average monthly coverage rate on intervention for MSM,increased from 49000 to 252000,and from 8.6％ to 78.5％ respectively.The FSW related indicators increased from 329 000 to 625 000,and from 30.9％ to 87.0％ respectively.Above indexes on the two populations had dropped slightly in 2013 and 2014.Sentinel surveillance data showed that knowledge and behavior indicators observed from the MSM and FSW populations increased annually.The coverage of intervention programs on migrant workers increased from 4.7％ to almost 10.0％,but the surveillance data on migrant men showed that the knowledge and behavior indicators were still lower than the other high-risk groups.Conclusion Intervention related to sexual transmission on HIV/AIDS among high-risk populations were effectively implemented,with some achievements seen.However,as sexual contact currently became the main route of AIDS epidemic,new challenges called for serious attention.

Comparison between methods as polling booth survey and face-to-face interview in understanding the high-risk behavior among HIV-positive clients of female sex workers / 中华流行病学杂志

<p><b>OBJECTIVE</b>Face-to-face interview (FTFI) and polling booth survey (PBS) were applied to compare the high risk behavior among HIV-positive clients of female sex workers (CFSWs).</p><p><b>METHODS</b>This study was conducted in antiretroviral therapy (ART) out-patients centers in Hengyang city, where clients who had been informed on their HIV-positive status for 6 months or longer were recruited. FTFI was first used to tackle on 8 sensitive questions related to sexual behavior, followed by PBS to poke on the same questions. Results from FTFI and PBS were then compared.</p><p><b>RESULTS</b>Compared with FIFI, results in the PBS showed higher proportion of participants who reported "having had history of sexually transmitted diseases before knowing that they were infected with HIV" (40.6% vs. 24.2%) but lower proportions on "frequency of having sex with regular sexual partner less than 4 times per month" and "using condoms consistently with regular sexual partners in past 6 months (44.4% vs. 63.0%)". There were no significant differences in the remaining 5 questions shown in the results from the two methods.</p><p><b>CONCLUSION</b>HIV-positive CFSWs continued to practice unsafe sexual behaviors after knowing their HIV related status. Compared with FTFI, PBS seemed to have revealed higher proportion of unsafe sex behaviors, so as to generated more reliable data. While comparing with PBS, the traditional FTFI might have underestimated the risk behaviors among those HIV-positive CFSWs.</p>

Loss to follow-up and associated factors in a cohort study among men who have sex with men / 中华流行病学杂志

<p><b>OBJECTIVE</b>To explore the associated factors on loss to follow-up among men who have sex with men (MSM) in a prospective cohort study.</p><p><b>METHODS</b>We recruited eligible HIV-negative MSM at baseline in eight cities from June to October 2009. Interviewer-administrated questionnaire and blood testings for HIV, syphilis and human simplex virus type 2, were accomplished upon enrollment, 6-month and 12-month follow-up visits in the program. Loss to follow-up was recorded at each visit in this cohort. Univariate and multivariate statistical analysis were conducted to examine the associated factors on loss to follow-up.</p><p><b>RESULTS</b>A total of 3196 eligible MSM were enrolled at the baseline study. During one year of follow-up, 894 (28.0%) of them dropped out thoroughly while 2302 (72.1%) showed up at least on one visit. Factors as MSM who were at age 25 or younger, resided locally less than 1 year, being unemployed, self-recognized as heterosexuality or bisexuality, never taking HIV testing in the past year, having had sex with women in the past 6 months etc., were more likely to withdraw from the follow-up visits. Conclusion Age, length of residency, sex orientation and history of HIV testing were associated with the loss of follow-up among MSM cohort in our study. These factors should be considered in this kind of study design in the future.</p>

Effects of bkdAB interruption on avermectin biosynthesis / 生物工程学报

In this study, Streptomyces avermitilis Bjbm0006 which produces four avermectin B components was used as an original test strain. A replacement plasmid containing a gene cluster bkdAB (branched-chain alpha-keto acid dehydrogenase gene) involved in the biosynthesis of avermectin B in S. avermitilis Bjbm0006 was constructed by means of PCR technique and then named as pHJ5821 (pHZ1358::bkdAB&erm). A recombinant strain Bjbm5821 was obtained after the gene cluster was interrupted by double crossover. This strain was tested in laboratory conditions and analysed by PCR using the total DNA as template. The HPLC analysis showed that the strain Bjbm5821 synthesized the same 'a' components Bla and B2a as the original strain did. However, It lost the ability for the production of 'b'components for example B1b and B2b. A novel compound was detected in fermentation products. The results of present study suggests that the production of gene cluster bkdAB may play a main role similar to alpha-ketoisovaleric acid dehydrogenase in the pathway of avermectin synthesis.

Combined Therapy on Hepatoblastoma and Evaluation of Relative Factors on Prognosis of It / 实用儿科临床杂志

Objective To explore a more reasonable and effective therapeutic regimen and evaluate prognostic factors in hepatoblastoma patients after combined therapy.Methods Sixteen patients diagnosed on hepatoblastoma between Jan.2000 and Nov.2007 were reviewed and followed-up.Resection with chemotherapy was taken among 16 cases.Chemotherapy included pre-operation and post-operation.Five cases were cured by transcatheter arterial chemombolization(TACE).Six cases were cured by single chemotherapy(both TACE and single chemotherapy were taken in 2 cases).Five cases weren't cured by pre-operation chemotherapy.Nine cases were subjected to curative resection,3 cases to alleviative resection,2 cases with single chemotherapy,1 case with single TACE,and 1 case refused operation and left hospital.Their mean survival duration was 13.5 months(3-98 months).SPSS 13.0 software was used to analyze the data.Results The total survival rate of cases as stage Ⅳ as lower than cases as stage Ⅰ,Ⅱand Ⅲ.Both alpha-fetoprotein(AFP)100 000 ?g/L cases had worse survival rate.The prognosis of mixed type was better than fetal type,embryonal type and anaplasia type.The survival rate of cases with standard chemotherapy was higher than cases with unstandard chemotherapy.And the surgical resection cases had better survival chance than non-surgical resection cases.The survival rate of surgical residual cases was worse than non-surgical residual cases.Conclusions Chemotherapy can improve the total survival rate and long-term survival rate of hepatoblastoma patients.TACE is a safe and effective choice for hepatoblastoma patients.We need to be alert and make the diagnosis as early as possibe,and treat it early and properly.