[Remediation of Petroleum-Contaminated Soil Using a Bioaugmented Compost Technique].

Bioaugmented compost was created by inoculating petroleum-degrading bacteria into mature compost. The petroleum hydrocarbon degradation efficiencies were investigated by applying this enhanced compost to petroleum-contaminated soil under low temperatures. The results showed that the degrading bacteria can be enriched in the mature compost. After 30 d of remediation, the removal efficiency of TPH, alkanes, and PAHs in the soil was 27.0%, 19.6%, and 10.0%, compared to natural attenuation (CK), which was 4.5%, 9.5%, and 2.3%, respectively. In response to remediation, the relative abundance of Proteobacteria and Actinobacteria phyla decreased from 53.4% and 25.9% to 48.9% and 14.1%, respectively, and Bacteroidetes phylum increased from 5.0% to 24.5%. At the genus level, the relative abundance of Acinetobacter and Pseudomonas increased from 0.02% and 3.4% to 15.2% and 4.6%, respectively. The results indicated that the bioaugmented compost may efficiently facilitate and speed up the bioremediation of petroleum-contaminated soil under low-temperature conditions. Soil microbial diversity and structure of microbial communities are sensitive to the remediation.

Presence of immune memory and immunity to hepatitis B virus in adults after neonatal hepatitis B vaccination.

Neonatal vaccination against hepatitis B virus (HBV) infection was launched in the 1980s in Qidong, China, where HBV and hepatocellular carcinoma were highly prevalent. Presence of immune memory and immunity against HBV in adults needs to be clarified. From a cohort of 806 who received plasma-derived Hep-B-Vax as neonates and were consecutively followed at ages 5, 10, and 20 years, 402 twenty-four-year-old adults were recruited for booster test. Among them 4 (1%) were found to be HBsAg(+), 27 (6.7%) were HBsAg(-)anti-HBc(+), 121 (30.2%) were HBsAg(-)anti-HBc(-)anti-HBs(+), and 252 (62.4%) were HBsAg(-)anti-HBc(-)anti-HBs(-). Of them, 141 subjects with HBsAg(-)anti-HBc(-) were boosted with 10-µg recombinant HBV vaccine on day-0 and 1-month. The conversion rates of anti-HBs ≥ 10 mIU/ml on D10-12 and 1-month post-booster were 71.4% and 87.3% respectively in the vaccinees who were anti-HBs(+) at age 5, higher than in those who were anti-HBs(-) at age 5, 57.5% and 80.0% respectively, but no statistically significant. After the second dose of booster, all subjects with anti-HBs(+) at age 5 had anti-HBs >500 mIU/ml. However, 6/40 subjects, with anti-HBs(-) at age 5, had anti-HBs <10 mIU/ml, geometric mean concentration was 3.6 (95% CI 2.0-7.7). Of the subjects received booster, 44 subjects were determined the presence of T cell immunity on D10-12, 41 had HBsAg-specific T cells detectable, including 7/10 subjects whose anti-HBs were <10 mIU/ml 10-12 days post-booster. Among 27 HBsAg(-)anti-HBc(+) subjects, 19 had detectable serum HBV-DNA, and an "a" epitope mutation was found in 1/5 HBV isolates. One subject who was anti-HBc(+) at age 20 converted into HBsAg(+) 4 years later. The adults received neonatal HBV vaccination had immune memory and immunity against HBV infection. However, 31.9% of neonatal HBV vaccinees who responded weakly at an early age might be susceptible to HBV infection after childhood.

Occult HBV infection in anti-HBs-positive young adults after neonatal HB vaccination.

Previous follow-up on our neonatal HB vaccination cohorts with 80,000 individuals in Qidong, China, showed significant protective efficacy of immunization against HBV infection in childhood. However, some vaccinees were found to be HBsAg negative, but anti-HBs positive and anti-HBc positive at age 10-11 years. To study this phenomenon, 2919 vaccinees at age 19-21 years were sampled from the cohort. HBsAg(-), anti-HBs(+) and anti-HBc(+) were found in 124/2919 (4.2%) of the vaccinees. HBV DNA was detectable in 81/106 sample sera by using nested PCR. The PreS-S regions of HBV were sequenced in 41 randomly sampled sera. All the HBV isolates were HBV genotype C. Twenty one isolates (21/41, 51.2%) were identical to an HBV isolated in this area (GU434374). Only 4/41 (9.8%) showed mutations at the "a" epitope and three of them were G145A. The other mutations were found outside of the "a" epitope. Most of the sera contained <10,000 HBV copies/ml. Occult HBV infection happened in the young adults with HBsAg(-), anti-HBs(+) and anti-HBc(+) status, who received neonatal vaccination in Qidong.

Annexin II, a novel HSP27-interacted protein, is involved in resistance to UVC-induced cell death in human APr-1 cells.

Heat shock protein 27 (HSP27) is implicated in diverse biologic functions as a molecular chaperone. We found that HSP27 is involved in the protection of human cells against UVC lethality. To elucidate the molecular mechanisms underlying UVC resistance, we searched for HSP27-interacted proteins related to resistance in UVC-resistant human cells, APr-1. Three candidates for HSP27-interacted proteins were found from cell lysates using an affinity column coupled with GST-fused HSP27 protein. Interaction between HSP27 and two candidates, annexin II and HSP70, was confirmed by immunoprecipitation analysis. After UVC irradiation, the amount of the complex of HSP27 and annexin II decreased in the postnuclear fraction, while it increased in the nuclear fraction. Cells transfected with annexin II-siRNA were more susceptible to UVC lethality. These results suggest that annexin II is a novel HSP27-interacted protein which is involved in UVC resistance in human cells, at least those tested here.

Localization of ANP-synthesizing cells in rat stomach.

AIM: To study the morphological positive expression of antrial natriuretic peptide (ANP)-synthesizing cells and ultrastructural localization and the relationship between ANP-synthesizing cells and microvessel density in the stomach of rats and to analyze the distribution of the three histologically distinct regions of ANP-synthesizing cells. METHODS: Using immunohistochemical techniques, we studied positive expression of ANP-synthesizing cells in rat stomach. A postembedding immunogold microscopy technique was used for ultrastructural localization of ANP-synthesizing cells. Microvessel density in the rat stomach was estimated using tannic acid-ferric chloride (TAFC) method staining. Distribution of ANP-synthesizing cells were studied in different regions of rat stomach histochemically. RESULTS: Positive expression of ANP-synthesizing cells were localized in the gastric mucosa of rats. Localization of ANP-synthesizing cells identified them to be enterochrochromaffin cells (EC) by using a postembedding immunogold electron microscopy technique. EC cells were in the basal third of the cardiac mucosa region. ANP-synthesizing cells existed in different regions of rat stomach and its density was largest in the gastric cardiac region, and the distribution order of ANP-synthesizing cells in density was cardiac region, pyloric region and fundic region in mucosa layer. We have also found a close relationship between ANP-synthesizing cells and microvessel density in gastric mucosa of rats using TAFC staining. CONCLUSION: ANP-synthesizing cells are expressed in the gastric mucosa. EC synthesize ANP. There is a close relationship between ANP-synthesizing cells and microvessel density in gastric mucosa of rats. The distribution density of ANP-synthesizing cells is largest in the gastric cardiac region.

Molecular cloning of the rat beta-carotene 15,15'-monooxygenase gene and its regulation by retinoic acid.

BACKGROUND: beta-Carotene exhibits biological activity as provitamin A. Key step in vitamin A formation is the cleavage of beta-carotene to retinal by an enzyme designated as beta-carotene 15,15'-monooxygenase (BCM). Recently, it is reported that expression of BCM gene in the intestine is under feedback regulation by retinoic acid (RA). However, the regulation of BCM gene expression in various other tissues is still unknown. AIM OF THE STUDY: In the present study, we identified the full-length cDNA encoding the rat BCM gene and investigated the regulation of its expression in several tissues by RA in the presence of vitamin A deficiency. METHODS: We cloned the full-length cDNA encoding BCM gene from a rat intestinal cDNA library by hybridization screening. The BCM gene expression was examined using Northern blotting and reverse transcription-PCR analysis. We also investigated whether BCM gene expression was regulated by retinoids in several tissues of vitamin A-deficient rats. RESULTS: Sequence analysis of this clone revealed an open reading frame of 1,701 bases encoding a protein of 566 amino acids. The predicted polypeptide showed 94%, 81%, and 66% identity with mouse, human, and chicken BCM, respectively. Rat BCM mRNA was highly expressed in the intestine and liver, while there was weak expression in the testes, kidneys, and lungs. Immunoblotting revealed that rat BCM is a 64-kDa protein. BCM gene expression was increased in the small intestine by vitamin A deficiency compared with that in rats on a control diet, while this upregulation was suppressed by all-trans RA (ATRA) or 9-cis RA (9-cis RA). BCM gene expression in the lungs and testes was also suppressed by ATRA or 9-cis RA in rats with vitamin A deficiency. However, hepatic BCM gene expression was only decreased by ATRA and renal expression was not affected by either retinoid. As the small intestine is the major site of beta-carotene conversion, intestinal BCM gene expression may be more tightly regulated. CONCLUSION: These data suggest that BCM gene expression in several tissues may be down-regulated by RA at the level of conversion of beta-carotene to retinal. To prevent an excess of retinol, homeostasis may occur at the level of conversion of beta-carotene to retinal in several tissues.

Leupeptin-sensitive proteases involved in cell survival after X-ray irradiation in human RSa cells.

Proteases have received attention as important cellular components responsible for stress response in human cells. However, little is known about the role of proteases in the early steps of cell response after X-ray irradiation. In the present study, we first searched for proteases whose activity levels are changed soon after X-ray irradiation in human RSa cells with a high sensitivity to X-ray cell-killing. RSa cells showed an increased level of fibrinolytic protease activity within 10 min after irradiation with X-ray (up to 3 Gy). The induced protease activity was proved to be inhibited by leupeptin. We next examined whether this protease inducibility is related to the X-ray susceptibility of cells. Treatment of RSa cells with leupeptin prior to X-ray irradiation resulted in lowered colony survival and an increased ratio of G(2)/M-arrested cells and apoptotic cells. These results suggest that leupeptin-sensitive proteases are involved in the resistance of human RSa cells to X-ray cell-killing.

[Safety and immunogenicity of split vaccines of influenza viruses].

OBJECTIVE: To evaluate the safety and immunogenicity of influenza split vaccine. METHODS: According to the criteria of No.2002SL0043, instruction of application for new drug in clinical trial issued by the State Food and Drug Administration, 876 healthy persons were divided at random into vaccine group and control group. The trial was performed with the double blind method. Local and systemic adverse reactions were observed within 3 days after the vaccine group subjects were vaccinated. The antibody response to vaccines was detected with hemagglutination inhibition (HI) test. Numbers of seroconversions and HI titers greater than or equal to 40, as well as the mean geometric titer increase in HI were analyzed. RESULTS: There was no significant difference in local and systemic adverse reaction between vaccine and control groups. Meanwhile there was also no significant difference in seroconversions and protective level between two groups. However, there was obvious difference in mean geometric titer increase of antibody against H1N1 virus, while there was no significant difference in that of antibodies to H3N2 and type B viruses. CONCLUSIONS: The safety and immunogenicity of both vaccines are excellent.