Transcriptome and proteome analyses of adaptive responses to methyl methanesulfonate in Escherichia coli K-12 and ada mutant strains

<p>Abstract</p> <p>Background</p> <p>The Ada-dependent adaptive response system in <it>Escherichia coli </it>is important for increasing resistance to alkylation damage. However, the global transcriptional and translational changes during this response have not been reported. Here we present time-dependent global gene and protein expression profiles following treatment with methyl methanesulfonate (MMS) in <it>E. coli </it>W3110 and its <it>ada </it>mutant strains.</p> <p>Results</p> <p>Transcriptome profiling showed that 1138 and 2177 genes were differentially expressed in response to MMS treatment in the wild-type and mutant strains, respectively. A total of 81 protein spots representing 76 nonredundant proteins differentially expressed were identified using 2-DE and LC-MS/MS. In the wild-type strain, many genes were differentially expressed upon long-exposure to MMS, due to both adaptive responses and stationary phase responses. In the <it>ada </it>mutant strain, the genes involved in DNA replication, recombination, modification and repair were up-regulated 0.5 h after MMS treatment, indicating its connection to the SOS and other DNA repair systems. Interestingly, expression of the genes involved in flagellar biosynthesis, chemotaxis, and two-component regulatory systems related to drug or antibiotic resistance, was found to be controlled by Ada.</p> <p>Conclusion</p> <p>These results show in detail the regulatory components and pathways controlling adaptive response and how the related genes including the Ada regulon are expressed with this response.</p

Proteome-Level Responses of Escherichia coli to Long-Chain Fatty Acids and Use of Fatty Acid Inducible Promoter in Protein Production

In Escherichia coli, a long-chain acyl-CoA is a regulatory signal that modulates gene expression through its binding to a transcription factor FadR. In this study, comparative proteomic analysis of E. coli in the presence of glucose and oleic acid was performed to understand cell physiology in response to oleic acid. Among total of 52 proteins showing altered expression levels with oleic acid presence, 9 proteins including AldA, Cdd, FadA, FadB, FadL, MalE, RbsB, Udp, and YccU were newly synthesized. Among the genes that were induced by oleic acid, the promoter of the aldA gene was used for the production of a green fluorescent protein (GFP). Analysis of fluorescence intensities and confocal microscopic images revealed that soluble GFP was highly expressed under the control of the aldA promoter. These results suggest that proteomics is playing an important role not only in biological research but also in various biotechnological applications

Estimation of hospital-based HIV seroprevalence as a nationwide scale by novel method; 2002-2008 in Korea

<p>Abstract</p> <p>Background</p> <p>In Korea, approximately 70% of HIV-positive individuals are currently diagnosed in hospitals, while most HIV-positive patients were diagnosed at public health centers in 1980 s and 1990 s. However, there are no reporting systems to identify how many HIV tests are performed in the Korean hospitals different from public health centers and Blood centers. We estimated how many HIV tests were performed in hospitals and analyzed the nationwide hospital-based HIV seroprevalence in the present study.</p> <p>Methods</p> <p>Between 2002 and 2008, data included HIV tests on insurance claims in hospitals and the proportion of computerized insurance claims from the Health Insurance Review and Assessment Services. The number of HIV tests from the survey in the External Quality Assurance Scheme for hospital laboratories was collected to calculate the insurance claim proportion. HIV seroprevalence was estimated using data of tested individuals, including infected individuals. Statistical analysis was confirmed with the 95% confidence interval. Statistical significance was defined at p-values < 0.05.</p> <p>Results</p> <p>The number of HIV tests in hospitals increased from 2.7 million in 2002 to 5.0 million in 2008. The trend of HIV seroprevalence was decrease (1.5-1.3 per 10,000 individuals, P < 0.0028), except in 2002. The number of women tested was greater than men, and the proportion increased in older individuals and in small towns. Men had a higher annual HIV seroprevalence than women (P < 0.0001). The annual seroprevalence decreased in men (P = 0.0037), but was stable in women. The seroprevalence in the 30-39 year age group demonstrated higher than other age groups except 2008.</p> <p>Conclusions</p> <p>The nationwide hospital-based number of HIV tests and seroprevalence were estimated using a new method and seroprevalence trends were identified. This information will facilitate improvement in national HIV prevention strategies.</p

TOLL-LIKE RECEPTOR 2 AND MUC2 EXPRESSION ON HUMAN INTESTINAL EPITHELIAL CELLS BY GYMNOPHALLOIDES SEOI ADULT ANTIGEN

Goblet cell hyperplasia and mucin hypersecretion are important for the expulsion of the intestinal trematode, Gymnophalloides seoi, from mice. However, regulatory mechanisms underlying these processes remain elusive. To better understand the effects of G. seoi antigen on the host`s intestinal epithelial cells, we determined whether G. seoi induces expression of Toll-like receptors (TLRs) and in mucin-related (MUC) genes on a human intestinal epithelial cell line (HT29 cells). We treated HT29 cells with G. senior other adult helminth antigens and measured mRNAs of TLRs and MUCs. We also performed reverse transcriptase-polymerase chain reaction (RT-PCR) and flow cytometry to determine whether TLR and MUC expression is regulated by interferon (IFN)-gamma, interleukin-4, or monoclonal antibodies (mAbs) against G. seoi 46 kDa antigen. Gymnophalloides seoi antigen significantly induced expression of TLR2 and MUC2 in HT29 cells, and IFN-gamma was found to upregulate TLR2 expression on the surface of the cells. The expression of MUC2 was increased by IFN-gamma, but was decreased significantly via the combination of mAbs-to-human TLRs and G. seal antigen. These results demonstrated that G. seoi antigen upregulates TLR2 and MUC2 expression on human intestinal epithelial cells. These effects reflect a helminth-induced. IFN-gamma dependent, and innate mucosal immune mechanism in this human intestinal cell line.Guk SM, 2009, J PARASITOL, V95, P581, DOI 10.1645/GE-1807.1Ueno K, 2008, AM J RESP CELL MOL, V38, P263, DOI 10.1165/rcmb.2007-0336RCKraft M, 2008, EUR RESPIR J, V31, P43, DOI 10.1183/09031936.00103307Andrianifahanana M, 2007, ONCOGENE, V26, P7251, DOI 10.1038/sj.onc.1210532Ikeda H, 2007, LAB INVEST, V87, P559, DOI 10.1038/labinvest.3700556Mueller T, 2006, J IMMUNOL, V176, P5805Harris G, 2006, WORLD J GASTROENTERO, V12, P2149Yamauchi J, 2006, APMIS, V114, P270, DOI 10.1111/j.1600-0463.2006.apm_353.xSchroder K, 2006, IMMUNOBIOLOGY, V211, P511, DOI 10.1016/j.imbio.2006.05.007Chen XM, 2005, J IMMUNOL, V175, P7447Ding SZ, 2005, HELICOBACTER, V10, P193Campos-Rodriguezp R, 2005, PARASITE IMMUNOL, V27, P1Akira S, 2004, NAT REV IMMUNOL, V4, P499, DOI 10.1038/nri1391Cario E, 2004, GASTROENTEROLOGY, V127, P224, DOI 10.1053/j.gastro.2004.04.015KAMMANADIMINTI SJ, 2004, FASEB J, V18, P155Seo M, 2003, J PARASITOL, V89, P1080, DOI 10.1645/GE-3182RNMoncada DM, 2003, TRENDS PARASITOL, V19, P305, DOI 10.1016/S1471-4922(03)00122-3McGuinness DH, 2003, TRENDS PARASITOL, V19, P312, DOI 10.1016/S1471-4922(03)00123-5Chai JY, 2003, TRENDS PARASITOL, V19, P109, DOI 10.1016/S1471-4922(02)00068-5Reddy PK, 2003, EUR J CANCER, V39, P397Coelho PS, 2002, J LEUKOCYTE BIOL, V71, P837Rose MC, 2001, AM J RESP CELL MOL, V25, P533Shekels LL, 2001, DIGEST DIS SCI, V46, P1757, DOI 10.1023/A:1010622125040Gouyer V, 2001, BBA-MOL CELL RES, V1539, P71DEPLANCKE B, 2001, AM J CLIN NUTR, V73, P1131CHAI JY, 2001, KOREAN J PARASITOL, V39, P23Enss ML, 2000, INFLAMM RES, V49, P162ONAH DN, 2000, KOREAN J PARASITOLOG, V38, P209Dabbagh K, 1999, J IMMUNOL, V162, P6233Cohn L, 1999, J IMMUNOL, V162, P6178LEE SH, 1994, AM J TROP MED HYG, V51, P281NAWA Y, 1994, PARASITE IMMUNOL, V16, P333LEE SH, 1993, J PARASITOL, V79, P677CHOMCZYNSKI P, 1987, ANAL BIOCHEM, V162, P159BEAVER PC, 1984, CLIN PARASITOLOGY

Estimation of HIV Seroprevalence in Colorectal Hospitals by Questionnaire Survey in Korea, 2002–2007

AbstractObjectivesThe incidence of anal disease is higher among persons with human immunodeficiency virus (HIV) infection than among the general population. We surveyed the status of seroprevalence in colorectal hospitals in Korea.MethodsThe survey was conducted in colorectal hospitals in Korea from November to December 2008. The questionnaire was comprised of six topics about the status of HIV testing in colorectal hospitals. We gathered the data by website (http://hivqa.nih.go.kr/risk) or fax.ResultsAmong 774 colorectal hospitals contacted, 109 (14%) hospitals participated in the survey. Among these, 48 hospitals (44%) performed HIV tests in their own hospitals and 11 (23%) took HIV testing by rapid method. The main reason for recommending an HIV test was surgical operation (54%) followed by endoscope (11%) and health checkup (9%). The annual number of HIV tests increased from 58,647 (at 21 hospitals) in 2002 to 246,709 (at 58 hospitals) in 2007. HIV seroprevalence was >3.0 per 10,000 individuals during 2002–2005, decreased to 2.2 per 10,000 individuals in 2006 and rose to 2.8 per 10,000 individuals in 2007.ConclusionsHIV seroprevalence of colorectal hospitals was more than twice that of general hospitals in Korea. HIV surveillance systems based on colorectal hospitals for HIV/AIDS transmission prevention by early HIV diagnosis are needed

Increasing late diagnosis in HIV infection in South Korea: 2000-2007

<p>Abstract</p> <p>Background</p> <p>The number of Koreans diagnosed with human immunodeficiency virus (HIV) infections is increasing annually; however, CD4+ T-cell counts at diagnosis have decreased. The purpose of the present study was to identify clinical and epidemiologic associations with low CD4+ T-cell counts at the time of HIV diagnosis in a Korean population.</p> <p>Methods</p> <p>Data from 2,299 HIV-infected individuals with initial CD4+ T-cell counts measured within 6 months of HIV diagnosis and reason for HIV testing were recorded and measured from 2000 to 2007. Data were selected from the database of the Korea Centers for Disease Control and Prevention. Late diagnosis was defined by CD4+ T-cell counts <200 cells/mm³. Reasons for HIV testing were analyzed using logistic regression including epidemiologic variables.</p> <p>Results</p> <p>A total of 858 individuals (37.3%) were included in the late diagnosis group. Individuals with a late diagnosis were older, exposed through heterosexual contact, and demonstrated clinical manifestations of acquired immunodeficiency syndrome (AIDS). The primary reason for HIV testing was a routine health check-up (41%) followed by clinical manifestations (31%) of AIDS. The proportion of individuals with a late diagnosis was higher in individuals tested due to clinical symptoms in public health centers (adjusted odds ratio [AOR], 17.3; 95% CI, 1.7-175) and hospitals (AOR, 4.9; 95% CI, 3.4-7.2) compared to general health check-up. Late diagnosis annually increased in individuals diagnosed by voluntary testing both in public health centers (PHCs, P = 0.017) and in hospitals (P = 0.063). Routine testing due to risky behaviors resulted in earlier detection than testing secondary to health check-ups, although this difference was not statistically significant (AOR, 0.7; P = 0.187). Individuals identified as part of hospital health check-ups more frequently had a late diagnosis (P = 0.001)</p> <p>Conclusions</p> <p>HIV infection was primarily detected by voluntary testing with identification in PHCs and by testing due to clinical symptoms in hospitals. However, early detection was not influenced by either voluntary testing or general health check-up. It is important to encourage voluntary testing for early detection to decrease the prevalence of HIV infection and AIDS progression.</p

Photocatalytic degradation of polyamide 66 : evaluating the feasibility of photocatalysis as a microfibre-targeting technology

Wastewater treatment plants (WWTPs) have been identified as main contributors to releasing microfibres into the environment, however, WWTPs do not have microfibre-targeting technologies. In this study, photocatalysis is evaluated as a potential technology to treat microfibres in WWTPs by studying the degradation of polyamide 66 (PA66) microfibres using ultraviolet (UV) and titanium dioxide (TiO2). PA66 microfibres suspended in deionised water were exposed to different combinations of UV and TiO2. The degradation of the PA66 microfibres was monitored by changes in mass, carbonyl index and morphology using microbalance, infrared spectroscopy, and scanning electron microscopy. The formation of by-products from the degradation of the fibres was evaluated by measuring the chemical oxygen demand (COD) of the treated water. The degradation efficiency was optimised under UVC with a dose of 100 mg TiO2/L. Under these conditions, the PA66 microfibres presented a 97% mass loss within 48 h. The photocatalytic conditions applied generated a relatively low level of by-products (10 mg/L of COD). Therefore, photocatalysis with TiO2 an UVC could potentially be a feasible technology to treat microfibres in WWTPs, although more investigation is required to establish if this treatment leads to the formation of nanofibres. Further work is needed to translate the present optimised conditions to WWTPs