Features of airway remodeling in different types of Chinese chronic rhinosinusitis are associated with inflammation patterns

BACKGROUND

The remodeling patterns in different types of chronic rhinosinusitis (CRS) have rarely been compared, particularly the difference between eosinophilic and noneosinophilic CRS with nasal polyps (CRSwNP). Moreover, whether there is a link between remodeling and inflammation remains controversial.

OBJECTIVE

To directly compare the remodeling features of different CRS and to explore their relationship with inflammation in Chinese patients.

METHODS

Histologic characteristics of surgical samples were analyzed in 33 controls, 72 eosinophilic and 76 noneosinophilic CRSwNP, and 72 CRS without nasal polyps (CRSsNP) patients. Tissue samples from 38 controls, 26 eosinophilic and 26 noneosinophilic CRSwNP, and 32 CRSsNP patients were measured for mRNA and/or protein expression of profibrotic growth factors, metalloproteinases (MMPs), tissue inhibitor of metalloproteinases (TIMPs), hypoxia-inducible factor (HIF)-1α, interleukin (IL)-8, eosinophil cationic protein (ECP), and myeloperoxidase (MPO).

RESULTS

The amount of collagen decreased, whereas the edema scores increased, from CRSsNP to noneosinophilic CRSwNP and to eosinophilic CRSwNP. Transforming growth factor (TGF)-β2 protein levels were enhanced in CRSsNP compared with CRSwNP. TIMP-4 protein levels decreased in eosinophilic CRSwNP compared with noneosinophilic CRSwNP and CRSsNP. The number of neutrophils decreased from CRSsNP to noneosinophilic CRSwNP and to eosinophilic CRSwNP. ECP levels were only up-regulated in eosinophilic CRSwNP. ECP levels and neutrophil number correlated positively with the severity of edema and fibrosis, respectively. Neutrophils were the major sources of TGF-β2 in CRSsNP and noneosinophilic CRSwNP.

CONCLUSION

Distinct remodeling patterns are revealed for different types of CRS, particularly for eosinophilic and noneosinophilic CRSwNP. Tissue remodeling associates with inflammation in CRS.

An Ultrasensitive Electrochemical Immunosensor for Alpha-Fetoprotein Using an Envision Complex-Antibody Copolymer as a Sensitive Label

A novel strategy is presented for sensitive detection of alfa-fetoprotein (AFP), using a horseradish peroxidase (HRP)-functionalized Envision antibody complex (EVC) as the label. The Envision-AFP signal antibody copolymer (EVC-AFP Ab2) was composed of a dextran amine skeleton anchoring more than 100 molecules of HRP and 15 molecules of secondary antibody, and acted as a signal tag in the immunosensor. The sensor was constructed using the following steps: First, gold electrode (GE) was modified with nano-gold (AuNPs) by electro-deposition in HAuCl₄ solution. The high affinity of the AuNPs surface facilitates direct formation of a self-assembled thiolated protein G layer. Next, the coated GE was incubated in a solution of AFP capture antibody (AFP Ab1); these antibodies attach to the thiolated protein G layer through their non-antigenic regions, leaving the antigen binding sites for binding of target analyte. Following a sandwich immunoreaction, an EVC-AFP Ab2-AFP-AFP Ab1 immunocomplex was formed on the electrode surface, allowing large amounts of HRP on the complex to produce an amplified electrocatalytic current of hydroquinone (HQ) in the presence of hydrogen peroxide (H₂O₂). Highly amplified detection was achieved, with a detection limit of 2 pg/mL and a linear range of 0.005–0.2 ng/mL for AFP in 10 μL undiluted serum; this is near or below the normal levels of most cancer biomarker proteins in human serum. Measurements of AFP in the serum of cancer patients correlated strongly with standard enzyme-linked immunosorbent assays. These easily fabricated EVC-modified immunosensors show excellent promise for future fabrication of bioelectronic arrays. By varying the target biomolecules, this technique may be easily extended for use with other immunoassays, and thus represents a versatile design route.

Rubella epidemics and genotypic distribution of the rubella virus in Shandong Province, China, in 1999-2010

Background

The rubella vaccine was introduced into the immunization program in 1995 in the Shandong province, China. A series of different rubella vaccination strategies were implemented at different stages of measles control in Shandong province.

Methodology/Principal Findings

The average reported incidence rate of rubella cases remained at a low level in Shandong province after 1999. However, rubella epidemics occurred repeatedly in 2001/2002, 2006, and 2008/2009. The age of the onset of rubella cases gradually increased during 1999–2010, which showed that most cases were found among the 10 years old in 1999 and among the 17 years old in 2010. Phylogenetic analysis was performed and a phylogenetic tree was constructed based on the World Health Organization standard sequence window for rubella virus isolates. All rubella viruses isolated in Shandong province were divided into 4 genotypes: 1E, 1F, 2A, and 2B. Genotype 1E viruses accounted for the majority (79%) of all these viruses. The similarity of nucleotide and amino acid sequences among genotype 1E viruses was 98.2–100% and 99.1–100%, respectively. All Shandong genotype 1E strains, differed from international genotype 1E strains, belonged to cluster 1 and interdigitated with the viruses from other provinces in mainland China. The effective number of infections indicated by a Bayesian skyline plot remained constant from 2001 to 2009.

Conclusions/Significance

The gradual shift of disease burden to an older age group occurred after a rubella-containing vaccine was introduced into the childhood immunization schedule in 1995 in Shandong province. Four genotypes, including 1E, 1F, 2A, and 2B, were found in Shandong province during 2000–2009. Genotype 1E, rather than genotype 1F, became the predominant genotype circulating in Shandong province from 2001. All Shandong genotype 1E viruses belong to the genotype 1E/cluster 1; they have constantly circulated, and co-evolved and co-circulated, with those from other provinces.

Proteomic analyses of Sirt1-mediated cisplatin resistance in OSCC cell line

Oral squamous cell carcinoma (OSCC) accounts for about 90% of malignant oral lesions, and is recognized as the third most common cancer in developing nations and the sixth most common cancer worldwide. While chemotherapy remains the primary treatment for both resectable and advanced OSCC, most OSCC are naturally resistant to anticancer drugs, rendering new therapeutic avenues in dire need. Sirt1, a class III histone deacetylase, was linked to cisplatin resistance in several cancer types; however, the underlying mechanism is still unclear. Here, we demonstrated that overexpression of Sirt1 survived OSCC cell line Tca8113 under cisplatin treatment. Notably, BML-210, a chemical inhibitor of class III histone deacetylase, significantly abolished Sirt1-mediated cisplatin resistance in Tca8113 cells. Further, inactivation of endogenic Sirt1 by nicotinamide markedly increased chemo-sensitivity in cisplatin resistant sub-cell line Tca8113/CDDP. Proteomic strategy was applied to profile the differentially expressed proteins between pcDNA3.1-Sirt1- and mock vector-treated Tca8113 cells. Among 54 spots identified, 31 proteins were up-regulated and 23 proteins were down-regulated upon Sirt1 expression. Expression of four proteins with most significant alteration, including Annexin A4, Stathmin, SOD2 and thioredoxin, were validated by both RT-PCR and Western blot. Finally, we showed that Sirt1 could prevent cisplatin-induced ROS accumulation in Tca8113 cells. Our findings are considered as a significant step toward a better understanding of Sirt1-mediated cisplatin resistance.

Gamma-ray-induced mutagen sensitivity and risk of sporadic breast cancer in young women: a case-control study

Hypersensitivity to radiation exposure has been suggested to be a risk factor for the development of breast cancer. In this case-control study of 515 young women (≤ 55 years) with newly diagnosed sporadic breast cancer and 402 cancer-free controls, we examined the radiosensitivity as measured by the frequency of chromatid breaks induced by gamma-radiation exposure in the G2 phase of phytohemagglutinin-stimulated and short-term cultured fresh lymphocytes. We found that the average chromatid breaks per cell from 50 well-spread metaphases were statistically significantly higher in 403 non-Hispanic White breast cancer patients (0.52 ± 0.22) than that in 281 non-Hispanic White controls (0.44 ± 0.16) (P value < 0.001), and in 60 Mexican American breast cancer patients (0.52 ± 0.19) than that in 65 Mexican American controls (0.44 ± 0.16) (P value = 0.021), but the difference was not significant in African Americans (52 cases [0.45 ± 0.16] versus 56 controls [0.47 ± 0.16], P = 0.651). The frequency of chromatid breaks per cell above the median of control subjects was associated with two-fold increased risk for breast cancer in non-Hispanic Whites and Mexican Americans. A dose-response relationship was evident between radiosensitivity and risk for breast cancer (P (trend) < 0.001) in these two ethnic groups. We concluded that gamma-ray-induced mutagen sensitivity may play a role in susceptibility to breast cancer in young non-Hispanic White and Mexican American women.

Real-time elastography for the differentiation of benign and malignant breast lesions: a meta-analysis

The prognostic significance of ultrasound real-time elastography (RTE) in patients with breast lesions is controversial. There are two different diagnostic methods: the elasticity score (ES) and the strain ratio (SR). A meta-analysis was performed using a random-effect model to assess the overall sensitivity and specificity of RTE in the differentiation of breast lesions. MEDLINE, EMBASE, PubMed, and the Cochrane Library before February 2011 were searched. A total of 22 studies, which included 4,713 breast nodules in 4,266 patients were analyzed. The overall mean sensitivity and specificity for the diagnosis of malignant breast lesions by RTE were 0.834 [95% confidence interval (CI) 0.814-0.853] and 0.842 (95% CI, 0.829-0.854) for ES, and 0.883 (95% CI, 0.844-0.916) and 0.814 (95% CI, 0.786-0.839) for SR, respectively. RTE has a high sensitivity and specificity in the evaluation of breast lesions and can potentially reduce unnecessary breast biopsies.

Adoptive transfer of FTY720-treated immature BMDCs significantly prolonged cardiac allograft survival

A sphingosine 1 phosphate receptor modulator, FTY720, has been used to alleviate symptoms in allotransplantation and autoimmune disease models with impressive efficacy, while it only achieved moderate success in clinical trials. Infusion of immature bone marrow-derived dendritic cell (BMDC) progenitors before transplantation could induce donor specific tolerance. In this study, we investigated the possibility of using FTY720-DCs (FTY720-treated immature BMDCs) to prevent severe alloimmune response. Our results indicate that FTY720-DCs could markedly prolong graft survival compared with Ctrl-DCs (nonconditioned immature BMDCs) as manifested by reduced inflammatory infiltration into the graft. IFN-γ production by CD4(+) and CD8(+) T cells were significantly reduced, while FoxP3(+) regulatory T cells among CD4(+) T cells were upregulated. Although FTY720 seldom altered the phenotype or the phagocytosis of BMDCs in vitro, it severely hampered their capability to trigger antigen-specific and allogeneic T-cell response. When splenic T cells were co-cultured with FTY720-DCs, the proportion of regulatory T cells increased, accompanied by elevated IL-10 production. Consistently, infusion of FTY720-DCs could preferentially promote Treg proliferation and upregulate PD-1 expression on conventional T cells in allogeneic mature BMDC priming experiment. These results suggest that infusion of FTY720-DCs before cardiac transplantation could significantly prolong functional graft survival by acting as a balancer of alloimmune response.

Dynamic micro-Hall detection of superparamagnetic beads in a microfluidic channel

We report integration of an InAs quantum well micro-Hall magnetic sensor with microfluidics and real-time detection of moving superparamagnetic beads. Beads moving within and around the Hall cross area result in positive and negative Hall voltage signals respectively. Relative magnitudes and polarities of the signals measured for a random distribution of immobilized beads over the sensor are in good agreement with calculated values and explain consistently the shape of the dynamic signal.

[Analysis on molecular epidemiology of rubella virus in Shandong province during 2000-2007]

Analyze the genetic characteristics of sixteen strains of wild-type rubella viruses derived from Vero cells, Rk13 cells or Vero/slam cells, and isolated from throat samples in Shandong province during 2000-2007. The 1107 nucleotide sequence of nucleoprotein (E1) gene of these isolates were amplified by RT-PCR, and the PCR products were directly sequenced. Comparing with the gene tree that was constructed based on the 739 gene sequences of the WHO reference strains, twelve isolated strains belonged to 1E genotype, one strain belonged to 1F genotype, three strains belonged to 2A genotype. The first strain belonged to 1E genotype was isolated in Shandong province in 2001, then genotype 1E became dominant genotype of wild rubella viruses circulated. The 1E genotype circulated from 2006-2007 was different compared with that circulated from 2001 to 2002, but no significant deviation in temporal and geographic distribution was found. The strain belonged to Genotype 1F was only isolated during 2000 to 2001. The three strains of 2A genotype of rubella viruses were similar to rubella viruses vaccine strain (BRDII). The most nucleotide mutation of rubella viruses among the sixteen strains were nonsense mutation, and the amino acid sequences were highly conservative with no change in important antigen sites. Alike the previous reports, there was the same amino acid mutation in protein E1 at the site of 338 in all of the 1E genotype rubella viruses isolated during 2001- 2007 in Shandong (Leu338 --> Phe338).

Granzyme B is recovered by natural killer cells via clathrin-dependent endocytosis

When they recognize a target cell, natural killer (NK) cells mount an attack to kill the target by exerting their cytotoxicity via the exocytosis of cytotoxic granules. Although the details of this process (which includes the movement of cytotoxic granules in the immune synapse and their fusion with the plasma membrane, releasing granzymes and perforin into the synaptic cleft) are relatively better understood, the post-exocytosis regulation of the process is still largely unknown. Here we show that a clathrin-dependent endocytosis stimulated by target cell occurs in NK92 cell line, which is closely correlated with granzyme B recovery. Inhibition of the endocytosis significantly attenuates the cytotoxicity of NK92 cells. The NK cell recovery of its released effector molecules, in turn, suggests that endocytosis may well play a key role in the post exocytosis regulation of immune cells.

[Study on the content of curcumin by HPLC and the anti-tumor effect in vivo from different processed products of Curuma kwangsiensis]

OBJECTIVE

To determine curcumin content by HPLC and observe the antitumor effects in vivo from different processed products of Curuma kwangsiensis.

METHODS

We determined the content of curcumin by HPLC from different processed products of Curuma kwangsiensis and studied the anti-tumor effects in vivo by establishing S180 transplanted tumors model in mice.

RESULTS

The content of curcumin in different processed products of Curuma kwangsiensis as follows: primitive > vinegar-fried > vinegar-cooked. Different processed products had anti-tumor effects in the tumor-bearing mice. The vinegar-fried group and vinegar-cooked group showed obvious effect of inhibiting tumor growth than the primitive group.

CONCLUSIONS

Different processed methods may have some affection to the quality of Curuma kwangsiensis.

Iron deficiency anaemia can be improved after eradication of Helicobacter pylori

Background

Recent guidelines on iron deficiency anaemia (IDA) have confirmed the aetiological role of Helicobacter pylori (H pylori), but the relationship still remains controversial.

Methods

Starting in May 2009, searches of the following databases were undertaken: Medline (1966 to April 2009), Embase (1980 to April 2009), the Cochrane library (1800 to June 2008), Cochrane Central Register of Controlled Trials, Premedline, Healthstar, CBMdisc and the Chinese National Knowledge Infrastructure Database (January 1970 to April 2009). Changes in haemoglobin (Hb) concentrations and serum ferritin (SF) concentrations were recorded for intervention and control groups. The meta-analysis used random effect models and subgroup analyses were performed to explain heterogeneity.

Results

Eight studies met the inclusion criteria. All studies were performed in Asia, an area with a high incidence of IDA and H pylori. The pooled analysis of eight studies showed that H pylori eradication therapy can improve IDA, since changes in Hb and SF concentrations in the intervention groups were higher than in controls. The weighted mean difference (WMD) of Hb was 12.88 g/l (95% CI 6.03 to 19.74 g/l, p<0.00001); the WMD of SF was 10.05 μg/l (95% CI 5.48 to 14.63 μg/l, p<0.00001).

Conclusions

H pylori eradication therapy combined with iron administration is more effective than iron administration alone for the treatment of IDA. Eradication therapy has different effects on adults and children. Bismuth based triple therapy has a better response in terms of increased Hb and SF concentrations than proton pump inhibitor (PPI) based triple therapy.

[Morphological investigation of the protective effect of astragaloside preconditioning against ischemia-reperfusion lung injury in rats]

OBJECTIVE

To study the protective mechanisms of the astragaloside against ischemia-reperfusion lung injury in rats.

METHODS

Ischemia-reperfusion lung injury was induced in SD rats. Astragalus armour glucoside was dissolved in 1% of sodium carboxymethyl cellulose at different concentrations (8, 6, and 3 mg/ml) was intragastrically administered in the rats at the dose of 1 ml/100 g. Cellular and subcellular structural changes in the lung tissue were observed at the end of the experiment using optical and transmission electron microscope, with the wet/dry ratio of the lung tissue and myeloperoxidase (MPO) activity measured.

RESULTS

The wet/dry ratio and myeloperoxidase activity in the lung tissue were significantly higher in the model group than in the sham-operated group (P<0.05), and were significantly lowered by the treatment with astragalus armour glucoside at different doses (P<0.01 or 0.05), and the effect was especially obvious in rats receiving a moderate dose. Pulmonary capillary expansion, erythrocyte leakage and exudate in the alveolar space with obvious pathological changes in the type I and II epithelial cells were observed in model group. Pulmonary capillary expansion was reduced in rats treated with high, medium and low dose of Astragalus armour glucoside, and the medium dose group showed the most obvious effect, in which no edema fluid in the alveolar space or erythrocyte leakage was found with also reduced type II lung epithelial cell degranulation.

CONCLUSION

Astragaloside has obvious antioxidant effect in rats with ischemia-reperfusion lung injury, and a medium dose produces the best effect.

[Raman micro spectroscopic analysis of relationship between DNA degradation in tissue cells and postmortem interval]

The present work is to study the relationship between DNA degradation in tissue cells and estimation of postmortem interval, and to provide a new way for the estimation of postmortem interval (PMI). The tissue cells of kidney and liver in vitro obtained at different time points were kept in a controlled environment. The kidney tissue and liver tissue were taken out every 4 h, during 48-72 h after death at 25 degrees C. The DNA content in different tissue cells was examined by means of confocal Raman micro spectroscopy with an excitation wavelength of 532 nm. Results show that the relative peak intensities (I1 094/I2 923) of confocal Raman microscopy for the tissue cells decreased gradually with the prolongation of postmortem interval from 48 to 72 h after death, while the peak intensity at 1 094 cm(-1) was reduced obviously; and the peak intensity at 1 454 and 2 923 cm(-1) did not change significantly. It is concluded that the DNA content in tissue cells decreased gradually with the prolongation of postmortem interval from 48 to 72 h after death. There is a linear relationship between the degradation rate of DNA in the tissue cells and postmortem interval. This investigation shows that Raman micro spectroscopy is useful to the estimation of postmortem interval (PMI).

[A study on the targeting collect character of ferromagnetic drug carrier particles in microvasculature]

The transport and capture of therapeutic magnetic particles in the human microvasculature is studied numerically. Taking into account the dominant magnetic and fluidic forces on the particles, we have shown in our study that the particles can be directed to and concentrated at the desired zone which is within a few centimeters from the surface of the body. In addition, we have analyzed the influences of the malignant tissue depth, of the nanometers-iron nuclide content in a particle, and of the blood flow velocity and blood vessel diameter upon the captured efficiency.

[Magnetic fields ameliorates high-fat and high-protein diet-induced fatty liver in rats]

OBJECTIVE

To study the mechanism of the effect of low-frequency rotary constant magnetic field on high-fat and high-protein diet-induced fatty liver in rats.

METHODS

Fatty liver model was established in SD rats by feeding on a high-fat and high-protein diet daily. The enzyme activity changes in the serum and liver homogenate were detected at 10, 14, and 18 weeks, and the pathological changes of the liver were observed with optical and electron microscopy.

RESULTS

In magnetic field intervention group, the concentration of alanine aminotransferase and aspartate transaminase were significantly decreased, and the activity of lipoprotein lipase, hepatic lipase, superoxide dismutase and the concentration of malondialdehyde in the liver homogenate were significantly increased. Under optical microscope and electron microscope, the rats in the model group showed diffusive adipose degeneration in the hepatic cells with large lipid droplets, which became large vacuoles after fat extraction, indicating fatty necrosis. In magnetic field intervention group, remarkably smaller lipid droplets and lessened hepatic cell adipose degeneration were observed.

CONCLUSION

Low-frequency rotary constant magnetic field has beneficial effect on fat metabolism, leading to reduced lipid peroxidation and structural recovery of the degenerated hepatic cells.

Does Helicobacter pylori infection play a role in iron deficiency anemia? A meta-analysis

AIM: To perform a meta-analysis of observational studies and randomized controlled trials (RCTs) on the association between Helicobacter pylori (H. pylori) and iron deficiency anemia (IDA).

METHODS: A defined search strategy was used to search Medline, Embase, the Cochrane Library, Clinical Trials, Cochrane Central Register of Controlled Trials, Premedline and Healthstar. Odds ratio (OR) was used to evaluate observational epidemiology studies, and weighted mean difference (WMD) was used to demonstrate the difference between control and intervention groups.

RESULTS: Fifteen observational studies and 5 RCTs were identified and used for calculation. The pooled OR for observational studies was 2.22 (95% CI: 1.52-3.24, P < 0.0001). The WMD for hemoglobin (HB) was 4.06 g/L (95% CI: -2.57-10.69, P = 0.01), and the WMD for serum ferritin (SF) was 9.47 μg/L (95% CI: -0.50-19.43, P < 0.0001). Results were heterogeneous for all comparisons.

CONCLUSION: This meta-analysis on observational studies suggests an association between H. pylori and IDA. In RCTs, eradication of H. pylori can improve HB and SF levels but not significantly.

CD2AP is indispensable to multistep cytotoxic process by NK cells

CD2-associated protein (CD2AP) is a cytoplasmic protein which localizes to membrane ruffles, lipid rafts and the leading edges of cells. It is implicated in podocyte homeostasis, signal transduction, dynamic actin remodeling and also membrane trafficking during endocytosis and cytokinesis. CD2AP was reported to orchestrate receptor patterning and cytoskeletal polarity in T cell contacts and it could also modulate TCR signaling. However, whether it plays a role in NK cell killing remains unknown. In this study, we discovered that interfering with CD2AP expression strongly reduced cytotoxicity of human NK92 cell line and this effect was independent of FasL sensitivity of target cells. Conjugate formation and degranulation were impeded in NK92 cells after CD2AP knockdown. Upon encountering target cells, CD2AP in NK92 is enriched near contact site and colocalizes with FasL-bearing granules. In contrast, FasL-bearing granules were found rarely polarized toward cell contact site after CD2AP knockdown. Furthermore, by immunoprecipitation from NK92 cell lysates and transient expression studies in 293T and Hela cells, we demonstrated that CD2AP associates with FasL. Thus, CD2AP, through facilitating conjugate formation and directed transport of lytic granules, plays an important role in NK cells killing.

CpG ODN pretreatment attenuates concanavalin A-induced hepatitis in mice

T cell-mediated hepatic damage plays a key role in the pathogenesis of liver diseases such as autoimmune hepatitis, viral hepatitis and acute liver failure. CpG-containing oligodeoxynucleotides (CpG ODN), a ligand for toll-like receptor (TLR) 9, is widely used as an immunological adjuvant. In the present study, we investigated the effect of CpG ODN on T cell-mediated liver injury in a murine model of concanavalin A (Con A)-induced hepatitis. We found that the aminotransferase level was significantly decreased in CpG ODN pretreated mice and the survival of the mice was markedly prolonged. CpG ODN pretreatment inhibited NF-kappaB DNA binding activity. As a result, the systemic/liver levels of TNF-alpha and IFN-gamma were significantly suppressed. Furthermore, the activation of inflammatory cells was diminished by CpG ODN pretreatment. These results suggest that CpG ODN pretreatment protects the mice from Con A-induced liver injury via inhibiting hepatocyte apoptosis, inflammation and activation of lymphocytes.

[Discrimination of common oral streptococcus with metabonomics method]

OBJECTIVE

To evaluate the feasibility of identifying oral streptococcus by comparing their metabolic profiling, and to find a convenient and rapid way to discriminate oral microorganisms.

METHODS

The pure cultivation of Streptococcus sanguis ATCC 10556 and Streptococcus sobrinus 6715 (reference strain) from solid culture were respectively inoculated in TPY liquid medium. Then the growth quantity was measured periodically by turbidimetry and the growth curves of the inoculated bacteria were completed. The culture solutions in the stationary phase of the two bacteria were centrifuged, and then tested with the 1H-nuclear magnetic resonance (1H-NMR) spectrometer respectively. The gained free induction decay (FID) data were all inputted into MestReC Soft and finally transformed into metabolic profiling. The metabolic profiles were integrated segmentingly and the results were inputted into SIMCA-P Soft for principal components analysis (PCA).

RESULTS

The PCA results showed the obvious clustering phenomena and the points of two group data differentially centralized in two clusters. Therefore, the NMR-based metabonomics profiles can discriminate the two different kinds of bacteria.

CONCLUSION

The metabonomics can be expected to be a kind of promising useful method in quick discrimination of oral streptococcus.

Leader sequence is required for activity of transmembrane tumor necrosis factor-alpha

Transmembrane tumor necrosis factor alpha (tmTNF-alpha) has a variety of biological activities different from soluble TNF-alpha (sTNF-alpha), but the only difference in sequence is its leader sequence (LS). To investigate the effect of the LS on tmTNF-alpha activity, single amino acid substitutions in the LS and its linked extracellular mature domain were made in an in vitro translation system and in an intact cell system. Mutations at Met(-71) and Cys(-28) in the LS obliterated cytotoxicity of tmTNF-alpha, whilst their secretory form retained full activity compared to parental sTNF-alpha. The lost cytotoxicity of Met(-71) mutant tmTNF-alpha was partly due to a reduced receptor binding activity. In spite of full receptor binding activity, Cys(-28) mutant tmTNF-alpha failed to induce NO production and iNOS mRNA transcription via forward signaling, but synergized with sTNF-alpha in IL-8 mRNA transcription via reverse signaling. The Asp(143) mutant tmTNF-alpha lost the ability to bind TNFR and to kill MCF-7 cells, whilst its secretory form retained about 60% cytotoxicity of parental sTNF-alpha. Although the mutation at Phe(87) had full activity in both forms, its membrane form induced a change in cell death mode from apoptosis to necrosis, in contrast to wild-type TNF-alpha whose membrane molecule chiefly induced apoptosis and secretory molecule mainly caused necrosis in MCF-7, respectively. The data suggest that the LS may be required for maintaining the correct structure and the bioactivity of tmTNF-alpha.

[Research of liver tumor extraction based on transparency]

It is very difficult to use the conventional methods that are based on area and on border for extracting a region of intered such as liver tumor region with vague and irregular boundaries. This paper introduces Poisson matting that uses transparency (alpha value) as self-property of image and seeks its best result value to achieve the aim of extracting object. Meanwhile, this method is applied to the liver tumor CT picture experimental results. It makes improvement in two steps: computing image source a value; calculating foreground image F and background image B. Consequently, successful result is obtained.