Extreme value analysis of gut microbial alterations in colorectal cancer.

Gut microbes play a key role in colorectal carcinogenesis, yet reaching a consensus on microbial signatures remains a challenge. This is in part due to a reliance on mean value estimates. We present an extreme value analysis for overcoming these limitations. By characterizing a power-law fit to the relative abundances of microbes, we capture the same microbial signatures as more complex meta-analyses. Importantly, we show that our method is robust to the variations inherent in microbial community profiling and point to future directions for developing sensitive, reliable analytical methods.

TGF-ß1 promotes human hepatic carcinoma HepG2 cells invasion by upregulating autophagy.

OBJECTIVE: To study the role of TGF-ß1 in autophagy and invasion ability of human hepatic carcinoma HepG2 cells. MATERIALS AND METHODS: Cultured HepG2 cells were treated with different concentrations of TGF-ß1 for 24 h. The protein expression levels of autophagy relative marker LC3 and Beclin1 were detected by Western blot. The effect of TGF-ß1 on invasion ability of HepG2 cells was detected with transwell method. RESULTS: The results demonstrated that TGF-ß1 was able to activate autophagy of HepG2 cells in a dose-dependent manner. Autophagy inhibitor 3-methyladenine (3-MA) could reverse TGF-ß1 induced autophagy process. Also, TGF-ß1 significantly promotes the invasion ability of HepG2 cells; however, this process could effectively reverse by autophagy inhibitor 3-MA. CONCLUSIONS: TGF-ß1 enhances HepG2 cells invasion by upregulating autophagy.

Effects of Forage:Concentrate Ratio on Growth Performance, Ruminal Fermentation and Blood Metabolites in Housing-feeding Yaks.

The objective of this study was to determine the effect of forage: concentrate ratio (F:C) on growth performance, ruminal fermentation and blood metabolites of housing-feeding yaks. Thirty-two Maiwa male yaks (initial body weight = 207.99±3.31 kg) were randomly assigned to four dietary treatments (8 yaks per treatment). Experimental diets were: A, B, C, D which contained 70:30, 60:40, 50:50 and 40:60 F:C ratios, respectively. Dry matter intake and average daily gain in yaks fed the C and D diets were greater (p<0.05) than yaks fed the A and B diets. No differences were found in ruminal NH3-N, total volatile fatty acids, acetate, butyrate, valerate, and isovalerate concentrations. The propionate concentration was increased (p<0.05) in the C and D groups compared with the A and B diets. In contrast, the acetate to propionate ratio was decreased and was lowest (p<0.05) in the C group relative to the A and B diets, but was similar with the D group. For blood metabolites, no differences were found in serum concentrations of urea-N, albumin, triglyceride, cholesterol, low density lipoprotein, alanine aminotransferase, and aspartate aminotransferase (p>0.05) among treatments. Treatment C had a higher concentration of total protein and high density lipoprotein (p<0.05) than A and B groups. In addition, there was a trend that the globulin concentration of A group was lower than other treatments (p = 0.079). Results from this study suggest that increasing the level of concentrate from 30% to 50% exerted a positive effect on growth performance, rumen fermentation and blood metabolites in yaks.

Multicenter, double-blind, randomized clinical trial of parenterally administered Cefoselis versus Cefepime for the treatment of acute bacterial infections.

AIM: This study aims to evaluate the clinical efficacy and safety of intravenous Cefoselis injection for the treatment of acute moderate and severe bacterial infections. PATIENTS AND METHODS: A multicenter, double-blind, randomized clinical trial was carried out using Cefepime as control. Patients received 1.0 g of either Cefoselis or Cefepime for moderate infections or 2.0 g for severe infections at an interval of 12 hours for 7 to 14 days. A total of 276 patients (138 with Cefoselis, 138 with Cefepime) with respiratory or urinary tract infections were enrolled in the study. Up to 137 and 124 patients receiving Cefoselis and 132 and 125 patients receiving Cefepime were eligible for the ITT (intent to treat) and PP (per protocol) analyses, respectively. RESULTS: At the end of the treatment, the cure rates and effective rates were 59.68% (74/124) and 93.55% (116/124) with Cefoselis, and 56.00% (74/124) and 90.40% (116/124) with Cefepime. The bacterial eradication rates of the two groups were 90.32% and 93.85%, respectively. No statistical differences were observed on the above-mentioned parameters between the two groups (all p > 0.05). Adverse events, mainly mild aminotransferase elevation and mild leukopenia, were observed in 11.59% (16/138) and 13.77% (19/138) of patients with Cefoselis and Cefepime, respectively (p > 0.05). CONCLUSIONS: Cefoselis is an effective and safe choice against acute moderate and severe respiratory infections and UTI (urinary tract infection).

Association of MTHFR C677T polymorphisms and colorectal cancer risk in Asians: evidence of 12,255 subjects.

OBJECTIVES: To investigate the relationship of the MTHFR polymorphisms (C677T) and the risk of CRC by meta-analysis. METHODS: Relevant literatures concerning the association between the MTHFR C677T polymorphism and the risk of CRC were searched using the electronic database PubMed, EMBASE, Cochrane and China National Knowledge Infrastructure (CNKI). Odds ratio (ORs) and 95 % confidence intervals (CIs) were determined to assess the gene-disease association using fixed or random effect models, according to the heterogeneity among included studies. RESULTS: The study shows that the MTHFR 677 TT homozygous genotype significantly decreases the risk of CRC in Asians (TT vs. CC: OR = 0.82, 95 % CI 0.73-0.92; TT vs. CT: OR = 0.84, 95 % CI 0.75-0.94; TT vs. CC+TT: OR = 0.83, 95 % CI 0.75-0.93). CONCLUSION: This meta-analysis indicated that the MTHFR 677 TT homozygous genotype decreased the risk of CRC in Asians, while the MTHFR 677 CT heterozygous genotype did not contribute to CRC susceptibility.

Convective velocity reversal caused by turbulence transition in tokamak plasma.

Particle transport has been studied in the Tore Supra tokamak by using modulated ion cyclotron resonance heating to generate perturbations of density and temperature. For the first time, a reversal of the particle convective velocity and a strong increase in the turbulent particle flux have been clearly observed. When the mixed critical gradient ζc=R/L(T)+4(R/L(n))=22 is exceeded, the particle flux increases sharply and the convective velocity reverses from inward to outward. These observations are in agreement with quasilinear, gyrokinetic calculations. The critical gradient corresponds to a transition from an instability driven by the ion temperature gradient to the onset of another instability caused by trapped electrons.

Observation of a spontaneous particle-transport barrier in the HL-2A tokamak.

Using the profile analysis, the density perturbation transport analysis, and the Doppler reflectometry measurement, for the first time a spontaneous and steady-state particle-transport barrier has been evidenced in the Ohmic plasmas in the HL-2A tokamak with no externally applied momentum or particle input except the gas puffing. A threshold in density has been found for the observation of the barrier. The particle diffusivity is well-like, and the convection is found to be inward outside the well and outward inside the well. The formation of the barrier coincides with the transition between the trapped electron mode and the ion temperature gradient driven mode.

A method of particle transport study using supersonic molecular beam injection and microwave reflectometry on HL-2A tokamak.

A method of the particle transport study using supersonic molecular beam injection (SMBI) and microwave reflectometry is reported in this paper. Experimental results confirm that pulsed SMBI is a good perturbation source with deeper penetration and better localization than the standard gas puffing. The local density modulation is induced using the pulsed SMBI and the perturbation density is measured by the microwave reflectometry. Using Fourier transform analysis for the local density perturbation, radial profiles of the amplitude and phase of the density modulation can be obtained. The experimental results in HL-2A show that the particle injected by SMBI is located at about r/a=0.65-0.75. The position of the main particle source can be determined through three aspects: the minimum of the phase of the first harmonic of the Fourier transform of the modulated density measured by microwave reflectometry; the H(a) intensity profile and the local density increase ratio. The maximum of the amplitude of the first harmonic shifts often inward relative to the particle source location, which indicates clearly there is an inward particle pinch in this area. Good agreement has been found between the experimental results and the simulation using analytical transport model. The particle diffusivity D and the particle convection velocity V have been obtained by doing this simulation. The sensitivity in the transport coefficients of the amplitude and the phase of the density modulation has been discussed.

A retrospective study for the outcome of pulmonary resection in 49 patients with multidrug-resistant tuberculosis.

BACKGROUND: Outcome of treatment using only chemotherapy for multidrug-resistant tuberculosis is usually considered not to be satisfactory. The combination of chemotherapy with surgical treatment has been producing higher acid-fast bacilli (AFB) negative sputum conversion and longer survival rates. This treatment strategy may be the solution for patients with multidrug-resistant tuberculosis. MATERIALS AND METHODS: A retrospective review was performed of the medical records and laboratory findings of 49 patients with multidrug-resistant tuberculosis among 130 patients who underwent pulmonary resection for pulmonary tuberculosis between January 1995 and December 1999 at National Masan Tuberculosis Hospital, Korea. RESULTS: The mean number of drugs to which the patients were resistant was 4.5. Patients had a mean age of 35 years. Cavitary lesions on plain chest X-ray were shown in 43/49 patients (87.8%); 31 had positive sputum cultures preoperatively (63.3%). The surgical techniques used were as follows: 12 pneumonectomies, 28 lobectomies, seven lobectomies with segmentectomies or wedge resections, one wedge resection and one cavernoplasty. The AFB negative sputum conversion rate was 93.5% with continuous postoperative chemotherapy. There were no deaths after surgery. Postoperative complications that developed were six cases of air leakage over a week, one of postoperative bleeding and one of wound infection. CONCLUSIONS: This study demonstrated the effectiveness of pulmonary resection with postoperative chemotherapy in cases of multidrug-resistant tuberculosis. Although there are different ideas about indications for surgery and the length and content of postoperative drug regimens, pulmonary resection should be considered an effective measure in combination with chemotherapy for treatment of multidrug-resistant pulmonary tuberculosis.

Outcome of chemotherapy in 107 patients with pulmonary tuberculosis resistant to isoniazid and rifampin.

SETTING: National Masan Tuberculosis Hospital, Korea. OBJECTIVE: Treatment for multidrug-resistant tuberculosis (MDR-TB) is considered to be clinically important, but there are few reports on this topic. We therefore retrospectively evaluated the outcomes of chemotherapy only for pulmonary MDR-TB. DESIGN: We reviewed the clinical courses of 107 patients with pulmonary disease due to Mycobacterium tuberculosis resistant to rifampin and isoniazid who were under follow-up between March 1996 and June 1996 after hospitalization between January 1993 and January 1996. We performed a retrospective cohort study for all the patients' records. Their regimens were selected individually and preferably included four medications that they had not been given previously and to which the strain was fully susceptible. RESULTS: The 107 patients (mean age 38.3 years) had previously received a mean of five drugs, and were shedding bacilli that were resistant to a mean of four drugs. Of 63 patients with sufficient follow-up data, 52 (82.5%) responded to chemotherapy (as indicated by negative sputum cultures for at least three consecutive months); 11 (17.5%) had no response, as shown by continually positive cultures. In a univariate analysis, an unfavorable response was significantly associated with resistance to a greater number of drugs before the current courses of treatment (relative risk 21.5; 95% confidence interval 1.2-3.0; P < 0.05). The mean period of follow-up was 17 months. There was no subsequent relapse among the patients with responses, and there were no tuberculosis-related deaths. CONCLUSION: In this study, multidrug-resistant pulmonary tuberculosis responded relatively well to carefully selected regimens.

Chromosome analysis by fluorescence in situ hybridization of callus-derived regenerants in Allium cyaneum R.

Investigations were performed to confirm the optimal in vitro culture condition for callus induction and plant regeneration, to observe if somoclonal variation occurs among regenerated plants at the ploidy level and to analyse the chromosomal location of 5S and 18S-26S rRNA gene families using fluorescence in situ hybridization in callus-derived plants of Allium cyaneum. High-est callus initiation was achieved with bulb explants cultured on MS medium supplemented with 2,4-D and BAP at 1 mg l-1 each. A total of 195 plants was obtained when using MS medium supplemented with 1 mg l-1 NAA and 5 mg l-1 BAP; about 92% were diploid having 2n=16; 8% showed a variation in ploidy level. Using digoxigenin-labelled 5S rRNA and biotin-labelled 18S-26S rRNA gene probes, we compared the fluorescence in situ hybridization patterns of autotetraploid plants with the A. cyaneum wild type. The 5S rRNA gene sites were detected on the interstitial region in the short arm of chromosome 4 and on the interstitial region in both arms of chromosome 7. The 18S-26S rRNA gene sites were detected on the terminal region of the short arm, including the satellite of chromosome 5, as well as on a part of chromosome B. The chromosomal location of both rRNA genes in regenerated autotetraploid plants corresponded to those of the wild species.

Purification and properties of the nitrogenase of Azospirillum amazonense.

The nitrogenase of the free-living, microaerobic, N2-fixing bacterium Azospirillum amazonense (strain Y1) was purified by chromatography on DEAE-52 cellulose, by heat treatment, and by preparative polyacrylamide gel electrophoresis. The specific nitrogenase activities were 2,400 nmol of C2H4 formed per min per mg of protein for dinitrogenase (MoFe protein) and 1,800 nmol of C2H4 formed per min per mg of protein for dinitrogenase reductase (Fe protein). The MoFe protein was composed of a minimum of 1,852 amino acid residues, had an isoelectric point of 5.2, and contained 2 atoms of Mo, 24 atoms of Fe, and 28 atoms of acid-labile sulfide per molecule. The Fe protein had 624 amino acid residues and an isoelectric point of 4.6 and contained four atoms of Fe and six atoms of acid-labile sulfide per molecule. The purified MoFe protein showed two subunits with molecular weights of 55,000 and 50,000. The purified Fe protein revealed two polypeptides on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with apparent molecular weights of 35,000 and 31,000. The two Fe protein polypeptides were demonstrated with immunological techniques in the purified, highly active enzyme as well as in extracts. Also, Azotobacter vinelandii Fe protein showed two closely migrating polypeptides that migrated differently from the Fe protein polypeptides of Azospirillum brasilense or Rhodospirillum rubrum. The nitrogenase activity of Azospirillum amazonense Y1 was independent of Mn2+, and the addition of activating enzyme had no effect. No activating enzyme could be found in Azospirillum amazonense. Obviously, the nitrogenase system of Azospirillum amazonense Y1 is different from that of Azospirillum brasilense Sp7 and resembles the Azotobacter system.