Search

Sulfur (S) is an essential macronutrient for plants and a signaling molecule in abiotic stress responses. It is known that S availability modulates root system architecture; however, the underlying molecular mechanisms are largely unknown. We previously reported an Arabidopsis gain-of-function mutant sulfate utilization efficiency4 (sue4) that could tolerate S deficiency during germination and early seedling growth with faster primary root elongation. Here, we report that SUE4, a novel plasma membrane-localized protein, interacts with the polar auxin transporter PIN1, resulting in reduced PIN1 protein levels and thus decreasing auxin transport to the root tips, which promotes primary root elongation. Moreover, SUE4 is induced by sulfate deficiency, consistent with its role in root elongation. Further analyses showed that the SUE4-PIN1 interaction decreased PIN1 levels, possibly through 26 S proteasome-mediated degradation. Taken together, our finding of SUE4-mediated root elongation is consistent with root adaptation to highly mobile sulfate in soil, thus revealing a novel component in the adaptive response of roots to S deficiency.

To identify potential serum biomarkers for distinguishing between latent tuberculosis infection (LTBI) and active tuberculosis (TB).A proteome microarray containing 4,262 antigens was used for screening serum biomarkers of 40 serum samples from patients with LTBI and active TB at the systems level. The interaction network and functional classification of differentially expressed antigens were analyzed using STRING 10.0 and the TB database, respectively. Enzyme-linked immunosorbent assays (ELISA) were used to validate candidate antigens further using 279 samples. The diagnostic performances of candidate antigens were evaluated by receiver operating characteristic curve (ROC) analysis. Both antigen combination and logistic regression analysis were used to improve diagnostic ability.Microarray results showed that levels of 152 Mycobacterium tuberculosis (Mtb)-antigen- specific IgG were significantly higher in active TB patients than in LTBI patients (P0.05), and these differentially expressed antigens showed stronger associations with each other and were involved in various biological processes. Eleven candidate antigens were further validated using ELISA and showed consistent results in microarray analysis. ROC analysis showed that antigens Rv2031c, Rv1408, and Rv2421c had higher areas under the curve (AUCs) of 0.8520, 0.8152, and 0.7970, respectively. In addition, both antigen combination and logistic regression analysis improved the diagnostic ability.Several antigens have the potential to serve as serum biomarkers for discrimination between LTBI and active TB.

Glioma is the most common brain malignancy and has a very poor prognosis. The current treatment options have a minimal benefit on prolonging patient survival time. Accumulating data have shown that the WNT signaling pathway has a critical function in the progression and invasion of glioma. Thus, targeting WNT signaling appears to be an effective anti‑glioma strategy. TIKI2 was recently found to suppress the activation of the WNT signaling pathway by post‑translationally modifying secreted WNT proteins. The implication of TIKI2 aberrance in cancers and its potential therapeutic effect, however, has not been studied. In the present study, a glioma‑specific adenoviral vector was constructed, which was regulated by response elements of miR‑124, to express TIKI2 in glioma cells (Ad‑TIKI2‑124). Ad‑TIKI2‑124 was found to potently suppress the activation of WNT signaling in glioma cells. This inhibitory effect on the WNT signaling pathway lead to the reduction in proliferation, colony formation ability and invasion of glioma cell lines. In addition, animal experiments confirmed that the expression of the Ad‑TIKI2‑124 construct could compromise the tumorigenicity of glioma cells in vivo. Furthermore, this glioma‑selective TIKI2 expression protected normal cells from toxicity. In conclusion, the present study demonstrated that adenovirus‑mediated TIKI2 therapy may be used for glioma treatment and therefore warrants further clinical studies.

Sulfur is an essential macronutrient for plants with numerous biological functions. However, the influence of sulfur nutrient availability on the regulation of root development remains largely unknown. Here, we report the response of Arabidopsis thaliana L. root development and growth to different levels of sulfate, demonstrating that low sulfate levels promote the primary root elongation. By using various reporter lines, we examined in vivo IAA level and distribution, cell division, and root meristem in response to different sulfate levels. Meanwhile the dynamic changes of in vivo cysteine, glutathione, and IAA levels were measured. Root cysteine, glutathione, and IAA levels are positively correlated with external sulfate levels in the physiological range, which eventually affect root system architecture. Low sulfate levels also downregulate the genes involved in auxin biosynthesis and transport, and elevate the accumulation of PLT1 and PLT2. This study suggests that sulfate level affects the primary root elongation by regulating the endogenous auxin level and root stem cell niche maintenance.

L-Cysteine plays a prominent role in sulfur metabolism of plants. However, its role in root development is largely unknown. Here, we report that L-cysteine reduces primary root growth in a dosage-dependent manner. Elevating cellular L-cysteine level by exposing Arabidopsis thaliana seedlings to high L-cysteine, buthionine sulphoximine, or O-acetylserine leads to altered auxin maximum in root tips, the expression of quiescent center cell marker as well as the decrease of the auxin carriers PIN1, PIN2, PIN3, and PIN7 of primary roots. We also show that high L-cysteine significantly reduces the protein level of two sets of stem cell specific transcription factors PLETHORA1/2 and SCR/SHR. However, L-cysteine does not downregulate the transcript level of PINs, PLTs, or SCR/SHR, suggesting that an uncharacterized post-transcriptional mechanism may regulate the accumulation of PIN, PLT, and SCR/SHR proteins and auxin transport in the root tips. These results suggest that endogenous L-cysteine level acts to maintain root stem cell niche by regulating basal- and auxin-induced expression of PLT1/2 and SCR/SHR. L-Cysteine may serve as a link between sulfate assimilation and auxin in regulating root growth.

Mycorrhizas play a vital role in soil fertility, plant nutrition, and resistance to environmental stresses. However, mycorrhizal effects on plant resistance to herbivorous insects and the related mechanisms are poorly understood. This study evaluated effects of root colonization of tomato (Solanum lycopersicum Mill.) by arbuscular mycorrhizal fungi (AMF) Glomus mosseae on plant defense responses against a chewing caterpillar Helicoverpa arimigera. Mycorrhizal inoculation negatively affected larval performance. Real time RT-PCR analyses showed that mycorrhizal inoculation itself did not induce transcripts of most genes tested. However, insect feeding on AMF pre-inoculated plants resulted in much stronger defense response induction of four defense-related genes LOXD, AOC, PI-I, and PI-II in the leaves of tomato plants relative to non-inoculated plants. Four tomato genotypes: a wild-type (WT) plant, a jasmonic acid (JA) biosynthesis mutant (spr2), a JA-signaling perception mutant (jai1), and a JA-overexpressing 35S::PS plant were used to determine the role of the JA pathway in AMF-primed defense. Insect feeding on mycorrhizal 35S::PS plants led to higher induction of defense-related genes relative to WT plants. However, insect feeding on mycorrhizal spr2 and jai1 mutant plants did not induce transcripts of these genes. Bioassays showed that mycorrhizal inoculation on spr2 and jai1 mutants did not change plant resistance against H. arimigera. These results indicates that mycorrhizal colonization could prime systemic defense responses in tomato upon herbivore attack, and that the JA pathway is involved in defense priming by AMF.

On the morning of 14 April 2010, the M s 7.1 Yushu earthquake struck the eastern Tibet Plateau and an M s 6.3 aftershock followed west‐southwest of the mainshock epicenter one and a half hours later. The Yushu earthquake occurred on the northwestern continuation of the Ganzi–Xianshuihe fault zone and reactivated two segments of the fault. Ruptures associated with Yushu earthquake span a zone ≈70 km long, extending from south of Jielong in the west to south of Gyegu (Yushu) in the east. Detailed mapping of the surface rupture zone shows that it consists of two strike‐slip segments, the western and eastern segments, separated by the Longbao Lake step‐over (pull apart) basin. Our analysis suggests that the 18‐km‐long western segment of the surface rupture south of the Longbao Lake basin may have been associated with the M s 6.3 aftershock. The eastern rupture segment, which is inferred to be associated with the mainshock, is 32 km long. The main surface rupture can also be divided into two sections, with a 2‐km‐long gap between them. The surface rupture exhibits left‐lateral slip and is localized in a zone about 50 m wide along the present‐day trace of the Yushu fault. A single break, without splays or branching traces, characterizes most of the surface rupture zone. The observed magnitudes of surface displacement are typically 0.5–1 m with a maximum slip of ≈2 m. Both field observations and seismic inversion results suggest, rupture of M s 7.1 Yushu earthquake nucleated near the Longbao Lake step‐over basin in the west, propagated unilaterally eastward, and terminated within the east segment margin of the Yushu fault.

Tomato yellow leaf curl virus (TYLCV) is currently considered as one of the most devastating viruses in cultivated tomatoes (Solanum lycopersicum) worldwide. We reported here the development of a PCR-based method to quickly detect TYLCV using the primer pairs (TYLCV-F: 5'-ACG CAT GCC TCT AAT CCA GTG TA-3' and TYLCV-R: 5'-CCA ATA AGG CGT AAG CGT GTA GAC-3'), which was designed based on the genome sequence of TYLCV. A TYLCV-specific band of 543 bp was amplified from infected tomato plants. This protocol provides a rapid, reliable, and sensitive tool for molecular detection and identification of TYLCV in the industrial seedling and virus resistance breeding to facilitate safe and sustainable production of tomato.

In this paper, a new genetic algorithm method to optimize the frequency selective surface(FSS) is presented. The optimization speed and definition are promoted by limiting the parameter range and changing the genetic basis. A new cost function is introduced to optimize the multi-frequency of FSS by multi-object optimization (MO). The cirque element was optimized by the optimization method, fabricated by the selective electroless plating on fabric and measured by the arch test system. Test result proves the simulated result coincide with measured result. Result shows that it’s possible to realize different optimizations based on the various applying by this method.

Interleukin 8 (IL8) is an important chemokine that elicits host immune response against tuberculosis (TB). However, whether there is an association between IL8 gene polymorphism and TB susceptibility in the Chinese population is unknown. IL8 gene was amplified and sequenced to search for nucleotide polymorphisms among the Chinese population. Four single nucleotide polymorphisms (SNPs) were identified, selected, and analyzed in a cohort of 438 patients with TB and 536 healthy controls. Allelic, genotypic, and haplotypic analysis demonstrated that the distribution of the four IL8 SNPs between patients with TB and healthy controls was not significantly different (P0.05). The four IL8 SNPs detected in this study were not associated with TB susceptibility in the Chinese population. Secretion of IL8 by peripheral blood cells was greatly stimulated upon exposure to Mycobacterium tuberculosis whole cell extract, but such enhanced secretion was not associated with the IL8 rs4073 alleles.

Sulfur is an essential macronutrient for plants with numerous biological functions. However, the influence of sulfur nutrient availability on the regulation of root development remains largely unknown. Here, we report the response of Arabidopsis thaliana L. root development and growth to different levels of sulfate, demonstrating that low sulfate levels promote the primary root elongation. By using various reporter lines, we examined in vivo IAA level and distribution, cell division, and root meristem in response to different sulfate levels. Meanwhile the dynamic changes of in vivo cysteine, glutathione, and IAA levels were measured. Root cysteine, glutathione, and IAA levels are positively correlated with external sulfate levels in the physiological range, which eventually affect root system architecture. Low sulfate levels also downregulate the genes involved in auxin biosynthesis and transport, and elevate the accumulation of PLT1 and PLT2. This study suggests that sulfate level affects the primary root elongation by regulating the endogenous auxin level and root stem cell niche maintenance.

L-Cysteine plays a prominent role in sulfur metabolism of plants. However, its role in root development is largely unknown. Here, we report that L-cysteine reduces primary root growth in a dosage-dependent manner. Elevating cellular L-cysteine level by exposing Arabidopsis thaliana seedlings to high L-cysteine, buthionine sulphoximine, or O-acetylserine leads to altered auxin maximum in root tips, the expression of quiescent center cell marker as well as the decrease of the auxin carriers PIN1, PIN2, PIN3, and PIN7 of primary roots. We also show that high L-cysteine significantly reduces the protein level of two sets of stem cell specific transcription factors PLETHORA1/2 and SCR/SHR. However, L-cysteine does not downregulate the transcript level of PINs, PLTs, or SCR/SHR, suggesting that an uncharacterized post-transcriptional mechanism may regulate the accumulation of PIN, PLT, and SCR/SHR proteins and auxin transport in the root tips. These results suggest that endogenous L-cysteine level acts to maintain root stem cell niche by regulating basal- and auxin-induced expression of PLT1/2 and SCR/SHR. L-Cysteine may serve as a link between sulfate assimilation and auxin in regulating root growth.

Currently, migration has become one of the risk factors of high burden of tuberculosis in China. This study was to explore the influence of mass migration on the dynamics of Mycobacterium (M.) tuberculosis in Beijing, the capital and an urban area of China.Three hundred and thirty-six M. tuberculosis strains from the Changping district, where the problem of urban migrants was more pronounced than in other Beijing regions, were genotyped by Spoligotyping, large sequence polymorphisms (LSPs 105 and 181), and variable number tandem repeat (VNTR) typing. Based on the genotype data, the phylogeny of the isolates was studied.In Changping district, the proportion of Beijing lineage M. tuberculosis isolates amounted to 89.0% (299/336), among which 86.6 % (252) belonged to the modern lineage. The frequency of modern Beijing lineage strains is so high (around 75% (252/336)) that associated risk factors affecting the tuberculosis epidemic cannot be determined. The time to the most recent common ancestor (TMRCA) of the Beijing lineage strains was estimated to be 5073 (95% CI: 4000-6200) years. There was no significant difference in the genetic variation of Beijing isolates from urban migrants and local residents.The clone of modern Beijing lineage M. tuberculosis, which is dominant in the Beijing area, most likely started to expand with the five thousand-year-old Chinese civilization. In the future, with the urbanization in the whole of China, modern Beijing lineage M. tuberculosis may gain the larger geographical spread.

Mycobacterium abscessus (M. abscessus) can cause a variety of human infections, involving the lung, skin and soft tissues, and is generally believed to be acquired from environmental sources. The aim of this study was to investigate the molecular diversity and antibiotic susceptibility of M. abscessus isolates as the basis for strategies to improve control and management of infection.Seventy M. abscessus isolates from patients attending the Guangzhou Thoracic Hospital were identified from 2003 to 2005 by biochemical tests, gas chromatography, polymerase chain reaction (PCR)-restriction analysis (PRA) of heat shock protein gene hsp65, and sequencing of the quinolone resistance determining regions (QRDRs) of gyrA. Susceptibilities to six antibiotics were determined by micro-broth dilution. Isolates were genotyped using randomly amplified polymorphic DNA (RAPD) analysis.Most isolates (63/70; 90%) were susceptible to amikacin but rates of susceptibility to other antibiotics varied from moderate, clarithromycin (60%) and imipenem (43%), to low for ciprofloxacin and ofloxacin (3%), and 87% of isolates had intermediate susceptibility to cefoxitin. RAPD analysis showed that the 70 clinical isolates displayed 69 unique RAPD patterns.The high genetic diversity of isolates suggests that they are not transmitted from person to person but, presumably, are acquired independently from environmental sources. M. abscessus isolates displayed variable levels of susceptibility to all antibiotics tested, other than amikacin, indicating a need for routine susceptibility testing to guide treatment.

Estimation of the optimal concentrations of residual sugar in medium for a fed-batch culture of Baker's yeast has been studied and practiced. The concentrations, however, depended on different species and targets of the biomass, which was expected to be made. Kinetic changes of the residual phosphate salt in the medium conformed to a logarithmic process until the fourth hour during an 11-h culture. The parabolic method (see ref. 9 later in article) might be qualified to maintain the concentrations of residual sugar around 0.15 g/L. It was demonstrated that cell growth followed a sigmoid process during a fed-batch culture, because the cells consumed the nutrient with two metabolic pathways, one was for cell conversion and another was for non-cell conversion. With the parabolic method, we can estimate kinetics of cell growth and cell growth rate during the culture.

Tomato yellow leaf curl virus (TYLCV) is currently considered as one of the most devastating viruses in cultivated tomatoes (Solanum lycopersicum) worldwide. We reported here the development of a PCR-based method to quickly detect TYLCV using the primer pairs (TYLCV-F: 5'-ACG CAT GCC TCT AAT CCA GTG TA-3' and TYLCV-R: 5'-CCA ATA AGG CGT AAG CGT GTA GAC-3'), which was designed based on the genome sequence of TYLCV. A TYLCV-specific band of 543 bp was amplified from infected tomato plants. This protocol provides a rapid, reliable, and sensitive tool for molecular detection and identification of TYLCV in the industrial seedling and virus resistance breeding to facilitate safe and sustainable production of tomato.

It has been shown that jasmonate modulates the lateral root development through crosstalk with auxin in Arabidopsis thaliana. Exogenous application of jasmonate stimulates lateral root formation in wild type but inhibits lateral root formation in asa1-1. Our previous work has demonstrated that the lateral root formation defect of asa1-1 is co-related with jasmonte effect on PIN2 protein levels. To further elucidate the molecular mechanisms underlying jasmonate-mediated reduction of plasma membrane (PM)-resident PIN2 abundance, we have conducted a genetic screen to identify suppressors of asa1-1 (soa), which showed lateral root formation in the presence of jasmonate. Here, we described the basic characterization of soa563 and soa856. We showed that both soa563 and soa856 displayed restored lateral root formation in response to exogenous jasmonate. In addition, jasmonate-induced PIN2:GFP reduction was blocked in these two mutants. Our on-going effort to identify genes defined by these mutants promise to shed new light on the understanding of the molecular mechanisms controlling jasmonate-mediated regulation of PIN2 protein trafficking and turnover.

To investigate the association of the haplotype of the solute carrier family 11 member 1 (SLC11A1) gene with susceptibility to pulmonary tuberculosis in Tibetans.Four polymorphisms of the SLC11A1 gene [5' (GT)n, INT4, D53N, and 3' UTR] were investigated by denaturalization high performance liquid chromatography and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 140 patients (the patient group) and 139 PPD-positive healthy controls (the control group) of the Tibetan nationality from June 2004 until January 2005. The relationship between the haplotype and susceptibility to pulmonary tuberculosis in these patients was studied by chi2 test, and the linkage disequilibrium as well as the haplotype were analyzed by the SHESIS software.The haplotype frequencies of 5'(GT)9/INT4 G, 3'UTR TGTG/D543N G, 3'UTR TGTG del/D543N A were 64.8% (181/280), 76.6% (215/280), 12.0% (34/280) among the patients and 78.1% (217/276), 84.4% (235/276), 6.4% (18/276) among the controls. 5' (GT)9/INT4 G, 3'UTR TGTG/D543N G haplotypes rendered a lower risk (chi2 = 11.026, P0.01, chi2 = 6.547, P0.05, respectively), but 3'UTR TGTG del/D543N A haplotype a higher risk (chi2 = 6.547, P0.05) for tuberculosis.5' (GT)9/INT4 G, 3'UTR TGTG/D543N G and 3'UTR TGTG del/D543N A haplotypes of the SLC11A1 gene may be associated with the susceptibility of the Tibetan population to pulmonary tuberculosis.

To explore the influences of Mycobacterium tuberculosis on the levels of human acute monocytic leukemia cell line THP-1 apoptosis and death.Human acute monocytic leukemia cell line THP-1 were infected with Mycobacterium tuberculosis strains H37Ra, H37Rv, or Beijing genotype (BJTB), respectively, to construct the infection models. Cell apoptosis was detected using flow cytometry. The distribution of the apoptotic proteins was detected using immunofluorescent staining assays. The cells late apoptosis was detected using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling staining assays. The change of cell death was determined by Tyrpan blue staining assays.THP-1 apoptosis was induced by Mycobacterium tuberculosis strains H37Ra, H37Rv, and BJTB. H37Ra strongly induced THP-1 apoptosis, H37Rv weakly induced THP-1 apoptosis, and BJTB induced THP-1 apoptosis at the lowest level among these three Mycobacterium tuberculosis strains. On the contrary, BJTB strongly induced THP-1 death, H37Rv weakly induced THP-1 death, and H37Ra induced THP-1 death at the lowest level.Mycobacterial strains with different virulence induce different levels of apoptosis and death of THP-1 cells. Compared with highly virulent strains, attenuated strains induce more apoptosis and less death.

To investigate the application of heparin-binding haemagglutinin adhesin (HBHA) in tuberculosis (TB) diagnosis.We prepared native HBHA from cultivated Mycobacterium Bovis Calmetta Guerin (BCG) in Suton liquid medium. After BCG grew to the stationary status, native HBHA was acquired by specific CL-6B chromatography column binding heparin. At the same time, we cloned hbhA gene from Mycobacterium tuberculosis into PET-32alpha (+) expression vector. Recombinant HBHA from E. coli was obtained. Based on the native HBHA and recombinant HBHA, we chose 4 groups of pulmonary TB, extra-pulmonary TB, PPD (-) and PPD (+) healthy control with 47 in each group and conducted ELISA from serum for specific HBHA antibody level. At last we calculated the sensitivity and specificity in TB diagnosis by detection of anti-HBHA antibody level.The native HBHA could be diluted and purified with the PBS containing the 375 mmol/L NaCl by specific CL-6B chromatography column binding heparin; There was no significant difference in experimental result based on the natural and recombinant HBHA protein, also no difference between PPD (-) and PPD (+) healthy control groups. Serum antibody level by ELISA could distinguish pulmonary TB and ertra-pulmonary TB (t = 12.224, P0.05). The antibody level of the TB groups (pulmonary TB and ertra-pulmonary TB) was higher than the healthy control groups [PPD (+) and PPD (-) healthy control] (t =25.909, P0.05).Both recombinant and native HBHA can be used as immunological diagnosis in TB. It can be used in TB and especially extra-pulmonary TB diagnosis.

To determine the rpsL and rrs gene mutation in Mycobacterium tuberculosis (M. tuberculosis) and compare the consistency between the results of denaturing high-performance liquid chromatography (DHPLC) and those of DNA sequencing.The values of streptomycin minimum inhibitory concentration (MIC) against 215 M. tuberculosis clinical isolates, 115 being streptomycin-resistant and 100 being susceptible by a routine proportional method, were tested by DHPLC. DNA sequencing was conducted to detect the rpsL and rrs mutation.98 of the 115 streptomycin-resistant isolates (85.2%) harbored rpsL and/or rrs mutation, 76.5% of which being rpsL mutation (88/115). There was no significant correlation between the MIC values and mutation types. No mutation was found in all the susceptible isolates. There was a complete consistency between the DHPLC results and those of DNA sequencing.DHPLC can be regarded as a useful and powerful tool to detect the streptomycin resistance detection in M. tuberculosis.

To investigate the possible mechanisms of mycobacterial clearance induced by CpG-oligodeoxynucleotides (CpG-ODN) in mice.Eight-week-old female BALB/c mice were treated with intraperitoneal CpG-ODN (30 microg), while the control mice with normal saline. After 2 weeks, the control mice and the CpG-treated mice were infected with Mycobacterium tuberculosis (1 x 10(6) colony-forming units, H(37)Rv strain) through the tail vein. At 3 weeks, 4 weeks and 6 weeks after mycobacterial infection, the lung and the spleen tissues were examined for histopathological changes. Real time-PCR was performed to measure the messenger RNA (mRNA) of interleukin (IL)-12, IL-18, interferon (IFN)-gamma, IL-4, IL-10 and inducible nitric oxide synthase (iNOS) in the tissues. The homogenates of lungs and spleens were cultured, and the colonies were counted after a 4 weeks incubation period at 37 degrees C.At 3 weeks and 4 weeks of mycobacterial infection, CpG-ODN-pretreated mice showed less mycobacterial burden in the lungs and the spleens than that in the control mice [(0 +/- 0) x 10(6) CFU/g vs (32 +/- 11) x 10(6) CFU/g, (0 +/- 0) x 10(6) CFU/g vs (10 +/- 4) x 10(6) CFU/g; (26 +/- 4) x 10(6) CFU/g vs (56 +/- 8) x 10(6) CFU/g, (4 +/- 3) x 10(6) CFU/g vs (27 +/- 8) x 10(6) CFU/g]. At 4 weeks of mycobacterial infection, CpG-ODN-pretreated mice displayed increased levels of IL-18 mRNA, IFN-gamma mRNA, iNOS mRNA [(3.6 +/- 0.5, 1.6 +/- 1.1, 0.32 +/- 0.14) vs (0.20 +/- 0.10, 23.17 +/- 4.72, 16.18 +/- 5.09)], and decreased level of IL-12p40 mRNA (5.66 +/- 0.64 vs 14.54 +/- 1.89), but there was no difference in the levels of IL-4 mRNA and IL-10 mRNA in the lungs between CpG-ODN-pretreated mice and the control mice [(0.30 +/- 0.09 vs 0.26 +/- 0.05), (0.28 +/- 0.05 vs 0.29 +/- 0.08)]. CpG-ODN-pretreated mice displayed increased levels of IL-18 mRNA, IFN-gamma mRNA, iNOS mRNA [(5.54 +/- 1.29 vs 0.79 +/- 0.36), (0.52 +/- 0.07 vs 0.21 +/- 0.06), (9.07 +/- 1.81 vs 5.97 +/- 1.44)], and decreased levels of IL-12p40 mRNA, IL-4 mRNA and IL-10 mRNA [(2.10 +/- 0.27 vs 5.07 +/- 0.39), (0.23 +/- 0.10 vs 1.21 +/- 0.26), (0.10 +/- 0.04 vs 0.57 +/- 0.13)] in the spleens as compared with the control mice. In CpG-ODN-pretreated mice, expression level of IFN-gamma mRNA in the lungs at 6 weeks post-infection was higher than that at 4 weeks post-infection (0.95 +/- 0.27 vs 0.32 +/- 0.14).The activation of Toll-like receptor-9 (TLR-9) with CpG-ODN could enhance murine mycobacterial clearance in vivo. TLR-9-induced anti-mycobacterial activity involves increased expression of IL-18, IFN-gamma, and iNOS but decreased expression of IL-4 and IL-10.

To establish a rapid method for testing drug sussceptibility on Mycobacterium tuberculosis.Taking absolute Concentration method for drug susceptibility testing of M. tuberculosis as the "gold standard", we examined the drug-resistant of M. tuberculosis strain with nitrate reducrase assay (NRA) and the drug-resistant of M. tuberculosis germ in sputum with NRA.NRA and absolute concentration method was basically comparable with NRA susceptibility as 96.5% and the specificity was 100%, When comparing with traditional absolute concentration method, NRA could shorten the time about 3 weeks. Using NRA to test the drug-resistant of M. tuberculosis germ in sputum, its susceptibility was more than 66.7% and specificity was 100%, within 10-20 days.NRA could be used as a rapid drug susceptibility testing on M. tuberculosis.

To investigate the relationship between Fok I and Taq I polymorphisms of the VDR gene and the susceptibility of PTB in Chinese Tibetans.Two polymorphisms of the VDR gene were typed by PCR-RFLP among 140 patients and 139 healthy controls who had been sensitized to tuberculosis. The relationship among two polymorphisms and the susceptibility of PTB were studied, and cases were grouped according to the genotypes.The genotype FF, Ff, ff were observed in 60, 56 and 24 cases among tuberculosis group while in 70, 60 and 9 cases among control group. A significant increase of VDR genotype ff (mutant homozygotes) was observed in the PTB patients when compared to controls (P0.05, OR 3.111, 95% confidence interval 1.343-7.207). The genotype of TT were in 137 cases, Tt in 3 cases among patients while TT in 134 cases , Tt in 5 cases among controls. No significant difference in these genotype frequencies was observed between two groups (P0.05, OR 1.704, 95% confidence interval 0.399-7.272). Two polymorphisms didn't show linkage disequilibrium and D' is 0.475.The Fok I polymorphism of VDR gene might be associated with PTB in Chinese Tibetan population, but no evidences supported that the Taq I polymorphism were associated with PTB in Chinese Tibetan. The two polymorphisms didn't show linkage disequilibrium.

To investigate the protective effects and mechanisms of CpG oligodeoxynucleotides (CpG ODN) in mice infected with Mycobacterium tuberculosis.Ninety-six female BALB/c mice were randomized into 4 groups, namely CpG ODN treatment (A group), control ODN treatment (B group), infection control (C group) and healthy control (D group) (n = 24 each). A group and B group were treated once with CpG ODN or control ODN (30 microg/mouse) intraperitoneally 2 weeks before infection with Mycobacterium tuberculosis. 1 x 10(6) bacili in a volume of 300 microl saline was injected into the tail vein of mice from A group, B group and C group. Twelve mice from each group were sacrificed at 3 weeks postinfection. Pathologic changes in lung tissues were observed. The expression of Toll-like receptor 9 (TLR9) mRNA and cytokine mRNA was detected by RT-PCR. The numbers of viable bacteria in lung and spleen were counted. The rest 12 mice from each group were monitored for 60 days to observe the mortality.CpG ODN was shown to increase the survival time of mice infected with Mycobacterium tuberculosis. The body weights of mice from A group [(20.37 +/- 1.12) g] were higher than those of B group [(17.50 +/- 0.62) g] and C group [(17.15 +/- 0.97) g, P0.01]. The lung weights of mice from A group [(0.25 +/- 0.02) g] were similar to those of B group [(0.27 +/- 0.34) g, P0.05], but less than those of C group [(0.28 +/- 0.26) g, P0.01]. The spleens of mice from A group [(0.63 +/- 0.37) g] were larger than those of B group [(0.39 +/- 0.05) g] and C group [(0.38 +/- 0.02) g, P0.01]. The inflammation in lung tissue of mice from A group was less than that of B group and C group. There was no mycobacterial outgrowth in lungs and spleens of mice from A group. The expression of TLR9 mRNA in lungs and spleens of mice from A group (0.61 +/- 0.29 and 0.72 +/- 0.48) was similar to that in B group (0.58 +/- 0.35 and 0.64 +/- 0.28) and C group (0.60 +/- 0.32 and 0.65 +/- 0.31, P0.05), but higher than that in D group (0.11 +/- 0.08 and 0.26 +/- 0.22, P0.01). CpG ODN did not affect the expression of TLR9 mRNA. The expression of IFN-gamma mRNA in lungs and spleens of mice from A group (0.44 +/- 0.07 and 0.76 +/- 0.09) was higher than that in B group (0.19 +/- 0.05 and 0.22 +/- 0.05) and C group (0.16 +/- 0.04 and 0.18 +/- 0.08, P0.01). The expression of IL-6 mRNA in lungs and spleens of mice from A group (1.56 +/- 0.29 and 8.21 +/- 0.82) was higher than that in B group (0.86 +/- 0.55 and 0.16 +/- 0.09) and C group (0.78 +/- 0.21 and 0.06 +/- 0.04, P0.01). The expression of IL-4 mRNA in lungs and spleens of mice from A group (0.18 +/- 0.05 and 0.06 +/- 0.02) was lower than that in B group (0.31 +/- 0.06 and 1.22 +/- 0.01) and C group (0.35 +/- 0.04 and 1.31 +/- 0.31, P0.01). The expression of IL-10 mRNA in spleens of mice from A group (0.05 +/- 0.02) was lower than that in B group (0.57 +/- 0.09) and C group (0.65 +/- 0.15, P0.01).CpG ODN could increase the immunity of mice against tuberculosis through up-regulation of Th1 immunity and down-regulation of Th2 immunity.

To explore the feasibility of utilizing polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis combined with Southern blot to detect ofloxacin (OFLX)-resistant Mycobacterium tuberculosis, and figure out the boundary between the OFLX-susceptible and resistant Mycobacterium tuberculosis.OFLX-resistant Mycobacterium tuberculosis bacilli were induced in vitro and their minimal inhibitory concentration (MIC) and the minimal bactericidal concentration (MBC) were determined. The 320 bp segments of gyrA gene were amplified by PCR and their polymorphism was tested by SSCP from H(37)Rv, H(37)Ra and those induced OFLX-resistant strains. To prove the repeatability of PCR-SSCP combined with Southern blot, 36 clinical isolated OFLX-resistant strains were tested.All of the 85 OFLX-resistant mutations involved in this study were identified to have gyrA mutations. The results showed that there was an overlap if OFLX 10 microg/ml was used as a criteria for discriminating susceptible and resistant strains. Compared with the H(37)Ra, the similar single-stranded shift caused by the single-stranded conformation change was viewed in the 36 clinical isolated OFLX-resistant strains by PCR-SSCP combined with Southern hybridization.PCR-SSCP analysis combined with Southern blot can clearly distinguish OFLX-susceptible from OFLX-resistant strains. The results suggest that as a cut-off point between OFLX-susceptible and low-level OFLX-resistant to Mycobacterium tuberculosis, OFLX concentration of 10 microg/ml is considered to be a better one.

To investigate the expression of carcinoembryonic antigen (CEA) and cytokeratin19 (CK19) mRNAs in peripheral blood of patients with lung cancer and their correlation with staging, treatment response and prognosis.CEA and CK19 mRNAs in peripheral blood were detected by Taq Man reverse transcriptase-polymerase chain reaction (RT-PCR) in 78 patients with lung cancer before and after treatment, 30 patients with benign lung diseases and 30 healthy subjects. Serum CEA and CYFRA21-1 levels were also measured by enzyme linked immunosorbent assay (ELISA) in the 78 patients with lung cancer before treatment. The patients were followed for 2 years.The positive rates of CEA mRNA and CK19 mRNA in patients with lung cancer were 69.2% (54/78) and 62.8% (49/78), respectively, which were significantly higher than those in patients with benign lung diseases and the healthy controls (P0.01). The positive rate of CEA mRNA was the highest in adenocarcinoma, while the positive rate of CK19 mRNA was the highest in squamous cell carcinoma. There was no statistically significant difference among different stages (P0.05), The positive rates of CEA mRNA and CK19 mRNA were higher than those of serum CEA and CYFRA21-1. The positive rates of CEA mRNA and CK19 mRNA decreased significantly after surgical operation, but there was no significant change after chemotherapy. The median survival time (MST) for patients with a positive CEA mRNA before chemotherapy was shorter than those with a negative CEA mRNA (8.5 month and 11.7 month, respectively). The MST for patients with a positive CK19 mRNA before chemotherapy was shorter than those with a negative CK19 mRNA (8.9 month and 12.3 month, respectively). The rate of relapse and metastasis was higher in patients (29.4%) with a positive CEA mRNA preoperatively than those with a negative CEA mRNA (7.7%). The rate of relapse and metastasis was also higher in patients with a positive CK19 mRNA preoperatively (18.8%) as compared to those with a negative PCR result (7.1%).CEA and CK19 mRNAs can be used as markers in the detection of tumor micrometastases in lung cancer, and in evaluating surgical response and prognosis. The results suggest that the gene markers are better than the serum ones, and therefore may be useful for the early diagnosis of lung cancer.

To investigate the in-vitro interferon-gamma (IFN-gamma) release assay based on three different Mycobacterium tuberculosis antigens in the diagnosis of tuberculosis and Mycobacterium tuberculosis infections.The peripheral blood mononuclear cells (PBMC) were collected from the patients with tuberculosis (tuberculosis group, n = 57), patients with lung cancer (lung cancer group, n = 29), and healthy controls (healthy control group 2, n = 27). The PBMCs were co-cultured for 5 days with different antigens: purified protein derivatives (PPD) of tuberculin, early secretary antigenic target 6,000 protein (ESAT6) and 38,000 antigen. The protein levels of IFN-gamma were detected by ELISA, and the results were compared to those with the tuberculin skin test (TST).(1) For healthy controls, the TST was positively related to the history of BCG vaccination and the closeness of contact with sputum-positive tuberculosis patients (P = 0.047, P = 0.041 respectively). The ESAT6 based IFN-gamma release assay was only significantly related to the closeness of contact with sputum-positive tuberculosis patients (P = 0.005), but not to the history of BCG vaccination. (2) There was no significant difference of the TST results among the three groups (P0.05). (3) The receiver operating characteristic (ROC) curve analysis indicated that the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the IFN-gamma release assay based on 38,000 antigen were 64.9%, 89.3%, 77.0%, 86.0%, and 71.0% respectively for the diagnosis of tuberculosis.IFN-gamma release assay based on ESAT6 appears to be better than TST in the diagnosis of infection of Mycobacterium tuberculosis, while IFN-gamma release assay based on 38,000 may be helpful for the diagnosis of tuberculosis.

To assess the application of IS6110-restriction fragment length polymorphism (RFLP), Spoligotyping and mycobacterial interspersed repetitive unit (MIRU) in epidemiological studies of tuberculosis and to discuss the characteristics of Mycobacterium tuberculosis strains in different regions in China.Mycobacterium tuberculosis strains, with a total number of 158 isolates, were subjected to IS6110-RFLP, Spoligotyping and MIRU.The numbers of patterns produced by IS6110-RFLP, Spoligotyping, and MIRU typing were 118, 20 and 105 respectively. The discriminatory power of IS6110-RFLP was higher than that of Spoligotyping. However, when the copies of IS6110 were lower than 10, the discriminatory power of Spoligotyping improved obviously. The discriminatory power of MIRU typing was close to that of IS6110-RFLP for typing of Mycobacterium tuberculosis. In MIRU loci, there were four loci (loci 4, 10, 26, 40) with higher diversity. Significant differences among the Mycobacterium tuberculosis between Guangdong and other regions in clustered rate and the proportion of Beijing genotype (P0.05) were found. The clustered rates and the proportion of Beijing genotype in Guangdong were lower than that in other regions.The results of this study indicated that either IS6110-RFLP, Spoligotyping or MIRU technique was useful for epidemiological studies on tuberculosis in China and the strains in different regions had different characterishes in China.

To study the characteristics of katG, inhA, ahpC, kasA, and oxyR gene mutations in isoniazid-resistant clinical isolates of Mycobacterium tuberculosis.A total of 101 isoniazid-resistant and 43 susceptible strains of Mycobacterium tuberculosis were analyzed by PCR and sequence analysis of their katG, inhA, ahpC, kasA, and oxyR genes.(1) Sequencing of katG from 101 INH-resistant strains showed point mutations, small deletions or insertions in 81 isolates (80.2%), but no complete deletions were identified. The mutations at 16 position were found for the first time. Point mutations at position 315 were found in the genomes of 38.6% (39/101) of isoniazid-resistant strains. Low level isoniazid resistant strains (1 microg/ml) had higher mutation frequency at 315-Ser than high level isoniazid resistant strains (10 microg/ml; chi(2) = 9.31, P0.05). Mutations at position 463 were detected in 58 (57.4%) isoniazid-resistant strains. Arg463leu was also present in 23 of 43 susceptible strains. (2) Mutations in inhA genes were identified in 5 isoniazid-resistant isolates (4.9%). None of the susceptible strains contained any mutation in inhA genes. (3) Only 3 isolates in the 101 (2.97%) isoniazid-resistant clinical isolates had mutations in ahpC genes. No mutations were identified in the ahpC genes in 43 isoniazid-susceptible isolates. (4) Mutations in kasA genes were present in 17 of 101 (16.8%) isoniazid-resistant isolates. However, G312S was also present in 3 of 43 susceptible strains. (5) None of the isoniazid-resistant strains and susceptible isolates contained oxyR gene mutation. (6) Taken together, 91 of 101 (90%) isoniazid-resistant strains had mutations in katG, inhA, ahpC, and kasA genes which were associated with drug resistance.These studies provide further evidence supporting the association between katG, inhA, ahpC, and kasA gene mutations and INH resistance in Mycobacterium tuberculosis, while other mechanisms of INH resistant may exist.

To rapidly identify drug-resistant Mycobacterium tuberculosis using phenotypic and genotypic methods and to evaluate the clinical significance of rapid phenotypic susceptibility test by phage amplified biologically assay (PhaB).PhaB, DNA sequencing and polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) were performed on the 91 rifampicin (RFP)-resistant strains (including 82 multi-drug resistant Mycobacterium tuberculosis strains), 42 RFP-susceptible strains, 75 ofloxacin (OFLX)-resistant strains and 40 OFLX-susceptible strains at the same time.The results obtained using PhaB assay, DNA sequencing and PCR-SSCP were compared with the absolute concentration method. For RFP susceptibility, the accordance, sensitivity and specificity of PhaB were 93%, 92% and 95% respectively; the accordance, sensitivity and specificity of DNA sequencing were 93%, 90% and 100% respectively; those of PCR-SSCP were 90%, 86% and 100% respectively. For OFLX susceptibility, the accordance, sensitivity and specificity of PhaB assay were 95%, 95% and 95%; those of DNA sequencing were 80%, 71% and 98% respectively; those of PCR-SSCP were 75%, 63% and 98% respectively.PhaB assay is a low-cost, rapid, and sensitive method and shows high accordance with absolute concentration technology. It can give drug susceptibility test results within 48 - 96 h, and is a promising technology in clinical laboratory.

To establish the methodology of plasmid for gene knock-out in Mycobacterium BCG.We designed two pairs of primers for amplification of MDP1 gene and inserted two fragments into pKO plasmid, and then the recombinant plasmid for MDP1 gene knock-out was obtained, and named pKO-MDP1. Gene exchange took place within the genome of BCG after pKO-MDP1 plasmid was transformed into Mycobacterium BCG. The strain of Mycobacterium BCG with MDP1 gene knock-out was selected, and the curve of growth rate was studied.The target strain was that of the positive strain by two step PCR and one step sucrose counter selection, without growth in culture media with hygomycin. The value of A(600) per 12 hours was detected for sixteen days. A "S" shaped growth curve was detected. However, there was no significant difference in the growth rates between the wild type Mycobacterium BCG strain and the gene knock-out Mycobacterium BCG strain.The plasmid of pKO was a useful tool for gene knock-out in Mycobacteria. MDP1 maybe one of the factors influencing the growth rate, but it was not the only one.

To explore the epidemical distribution characteristics of Mycobacterium tuberculosis isolated from China.The M. tuberculosis strains were gained by multi-stratified grouping random sampling method from the nationwide random survey for the epidemiology of tuberculosis in China, 2000, and analyzed by IS6110-based RFLP and DR-based Spoligotyping DNA fingerprinting. These fingerprinting patterns were transferred into digital data and compared each other, and clustered by Gel compar4.1 Software. The clustering values in different TB patients were compared by chi(2) test and the risk factors for recent transmission were calculated by Odd Ratios.Two hundreds and four of 402 M. tuberculosis strains from this survey were determined to be "Beijing Genotype" M. Tuberculosis strain by DNA fingerprinting analysis. Three clusters M. tuberculosis strains sharing identical fingerprint pattern were found, including one cluster belong to a same family. There were significant difference between female and male, and younger (40 years old) and elder (or= 40 years old) (P0.05). Odds Ratio 1 showed youth [1.68 95% CI (1.01 - 2.80)] and male [2.04 95% CI (1.07 - 3.96)], but Odds Ratio 2 showed youth [0.3 95% CI (0.2 - 0.44)] and male [4.96 95% CI (2.77 - 9.00)].M. tuberculosis strains of Beijing Genotype are prevailing in China at present. Male and elder were shown to be significant risk factors for recent transmission. The infection source of M. tuberculosis could be traced by DNA fingerprinting.

To study nitric oxide (NO) production and cytokine expression by macrophages infected by M. tuberculosis H(37)R(v), and to compare the difference between dead and live M. tuberculosis in the induction of immune responses, and thus to show if dead bacteria could be a possible candidate for new vaccines.Reverse transcription-polymerase chain reaction (RT-PCR) and ELISA were used to measure the production of NO and cytokines in macrophages infected by H(37)R(v).Macrophages infected by viable M. tuberculosis produced more NO, IL-1, IL-12, IL-18, TNF-alpha and inducible nitric oxide synthases (iNOS), as compared with macrophages infected by dead bacteria. The number of bacteria was also an important factor determining the production of NO and cytokines.Viable M. tuberculosis H(37)R(v) can induce the activation of macrophages and the production of more NO and cytokines which play important roles in the host immune response. Heat-killed M. tuberculosis H(37)R(v) failed to induce activation of macrophages and the production of NO and cytokines, which makes it unlikely to be a candidate for vaccine development.