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Biomedical subjects

Ning Han

Publications and source records attributed to Ning Han.

11 recordsLinked to original sources

Expression of Helicobacter pylori urease subunit B gene in transgenic rice.

Helicobacter pylori ureB antigen gene was cloned to the 5'-end of gus (beta-glucuronidase) reporter gene between CaMV35S promoter and the octopine synthase (OCS) terminator in the plasmid, pCAMBIA13011. It was then introduced into rice genome by Agrobacterium-mediated transformation. A total of 30 regenerated plants with hygromycin resistance were obtained in the selection media. The putative transgenic individuals were tested for the presence of ureB in the nuclear genome of rice plants by PCR analysis. Expression of ureB gene in rice plants was verified by RT-PCR and Western blot analysis using polyclonal human antiserum for transcription and translation levels respectively. These results provide a basis for further studies on the accumulation level of UreB recombinant protein in transgenic rice and potential utilization of transgenic rice for delivery of edible vaccines against Helicobacter pylori.

Bacterial Proteins↗

Programmed cell death-involved aluminum toxicity in yeast alleviated by antiapoptotic members with decreased calcium signals.

The molecular mechanisms of aluminum (Al) toxicity and tolerance in plants have been the focus of ongoing research in the area of stress phytophysiology. Recent studies have described Al-induced apoptosis-like cell death in plant and animal cells. In this study, we show that yeast (Saccharomyces cerevisiae) exposed to low effective concentrations of Al for short times undergoes enhanced cell division in a manner that is dose and cell density dependent. At higher concentrations of Al or longer exposure times, Al induces cell death and growth inhibition. Several apoptotic features appear during Al treatment, including cell shrinkage, vacuolation, chromatin marginalization, nuclear fragmentation, DNA degradation, and DNA strand breaks, as well as concomitant cell aggregation. Yeast strains expressing Ced-9, Bcl-2, and PpBI-1 (a plant Bax inhibitor-1 isolated from Phyllostachys praecox), respectively, display more resistance to Al toxicity compared with control cells. Data from flow cytometric studies show these three antiapoptotic members do not affect reactive oxygen species levels, but decrease calcium ion (Ca(2+)) signals in response to Al stress, although both intracellular reactive oxygen species and Ca(2+) levels were increased. The data presented suggest that manipulation of the negative regulation process of programmed cell death may provide a novel mechanism for conferring Al tolerance.

Aluminum↗

[Observation on therapeutic effect of acupoint catgut embedding therapy on premenstrual syndrome].

OBJECTIVE: To compare clinical therapeutic effects of acupoint catgut embedding therapy and medicine on premenstrual syndrome, so as to search for the best method for this disease. METHODS: Eighty-eight cases were randomly divided into a catgut embedding group and a medication group. The catgut embedding group were treated with main points, Neiguan (PC 6), Sanyinjiso (SP 6), Danzhong (CV 17), Guanyuan (CV 4), Taichong (LR 3), and aduvant points, Back-shu, and the medicine group with oral administration of fluoxetine. After treatment of 3 months, their therapeutic effects were compared. RESULTS: The therapeutic effect of the catgut embedding group was better than that of the medication group with a very statistically significant difference (P < 0.005). CONCLUSION: Acupoint catgut embedding is a better therapy for premenstrual syndrome.

Acupuncture Points↗

[Effects of traditional Chinese medicine on CD4 + T cell counts and HIV viral loads during structured treatment interruption in highly active antiretroviral therapy].

OBJECTIVE: To explore the impacts of traditional Chinese medicine (TCM) on CD4 + T cell counts and human immunodeficiency virus (HIV) viral loads during the course of structured treatment interruption (STI) in highly active antiretroviral therapy (HAART). METHODS: Nineteen HIV/ADIS patients were treated for 14 months as follows: initiated with zidovudine/lamivudine + efavirdine for 6 months, then discontinued the therapy and treated with TCM instead for 2 months. HAART was then reinitiated for another 3 months, and then discontinued and replaced with TCM for another 3 months. The changes of CD4 + T cell counts and HIV viral loads were measured. RESULTS: During the first STI of HAART, 43.8% of patients had no viral rebounds one month later, and 62.6% had stable or increased immune functions; 18.8% had no viral rebounds two months later, and 43.8% had stable or increased immune functions. Changes of viral loads were not significantly different between these two months (P = 0.097), while CD4 + T cell counts significantly decreased two months later compared with one month later (P = 0.043). During the second STI of HAART, 33.3% of patients had no viral rebounds one month later, and 64.3% had stable or increased immune functions; 13.3% had no viral rebounds 3 months later and 46.6% had stable or increased immune functions. Changes of viral loads had significant difference (P = 0. 017), while CD4 + T cell counts at month 12 elevated significantly compared with the baseline (P = 0.014). CONCLUSIONS: TCM can suppress the viral rebounds during STI-HAART, maintain immune functions. However, this effect may decrease along with the prolongation of STI-HAART.

Adult↗

Cloning of Helicobacter pylori urease subunit B gene and its expression in tobacco (Nicotiana tabacum L.).

Vaccines produced by transgenic plants would have the potential to change the traditional means of production and inoculation of vaccines, and to reduce the cost of vaccine production. In the present study, an UreB antigen gene from a new Helicobacter pylori strain ZJC02 was cloned into the binary vector pBI121 which contains a CaMV35S promoter and a kanamycin resistance gene, and then transformed UreB into tobacco leaf-disc by Agrobacterium-mediated method. A total of 50 regenerated plants with kanamycin resistance were obtained in the selection media. The 35 putative transgenic individuals were tested and verified the presence and integration of the UreB into the nuclear genome of tobacco plants by PCR, PCR-southern, and Southern analyses. Expression of UreB gene in the tobacco plants was confirmed by RT-PCR and Western Blot analysis using polyclonal human antiserum. To our knowledge, this is the first report of the expression of Helicobacter pylori UreB antigen gene in a plant system, suggesting a major step in the production of plant-based vaccines for Helicobacter pylori.

Amino Acid Sequence↗

The leaf tonoplast V-H(+)-Atpase activity of a C3 halophyte Suaeda salsa is enhanced by salt stress in a Ca-dependent mode.

Suaeda salsa seedlings grown in Hoagland nutrient solution were treated with different concentrations of NaCl combined with two levels of Ca2+ (0 and 20 mmol/L) to study the effect of Ca2+ nutrition on the growth and activity of leaf tonoplast V-H(+)-ATPase. Increase of Ca2+ concentration in the solution markedly increased the relative growth quantity of S. salsa seedlings and Ca2+ and K+ concentration in the leaf cell sap under NaCl stress. The leaf V-H(+)-ATPase activity was significantly increased with increasing NaCl concentration under high Ca2+ application (20 mmol/L), but little changed under Ca2+ starvation (0 mmol/L). Western blot analysis showed that the leaf V-H(+)-ATPase of S. salsa was at least composed of A, B, D and c subunits, and their protein amounts were not affected by NaCl treatments under Ca2+ starvation (0 mmol/ L) with an exception of 100 mmol/L NaCl, but increased under high Ca2+ application (20 mmol/L). There was a positive correlation between activity of V-H(+)-ATPase and the protein amounts of the subunits. The results suggest that Ca2+ nutrition played an important role in the salt tolerance of S. salsa, and that enhancement of V-H(+)-ATPase activity under salt stress was Ca2(+)-dependent.

Blotting, Western↗

Root border cell development is a temperature-insensitive and Al-sensitive process in barley.

In vivo and in vitro experiments showed that border cell (BC) survival was dependent on root tip mucigel in barley (Hordeum vulgare L. cv. Hang 981). In aeroponic culture, BC development was an induced process in barley, whereas in hydroponic culture, it was a kinetic equilibrium process during which 300-400 BCs were released into water daily. The response of root elongation to temperatures (10-35 degrees C) was very sensitive but temperature changes had no great effect on barley BC development. At 35 degrees C, the root elongation ceased whereas BC production still continued, indicating that the two processes might be regulated independently under high temperature (35 degrees C) stress. Fifty microM Al could inhibit significantly BC development by inhibiting pectin methylesterase activity in the root cap of cv. 2000-2 (Al-sensitive) and cv. Humai 16 (Al-tolerant), but 20 microM Al could not block BC development in cv. Humai 16. BCs and their mucigel of barley had a limited role in the protection of Al-induced inhibition of root elongation, but played a significant role in the prevention of Al from diffusing into the meristems of the root tip and the root cap. Together, these results suggested that BC development was a temperature-insensitive but Al-sensitive process, and that BCs and their mucigel played an important role in the protection of root tip and root cap meristems from Al toxicity.

Aluminum↗

[The application of transgenic plant in evaluating the genotoxicity of environmental contaminants].

Environmental contaminants are powerful mutagenic factors for organisms. Several testing materials and methods have been used to assess the genotoxicity of environmental factors. Transgenic plants testing system can not only evaluate the level of genotoxicity, but also provide information on the genetic effects at molecular level. We introduce the use of transgenic plants in biomonitoring environmental factors.

Animals↗