Biomedical subjects

Quan Bai

Publications and source records attributed to Quan Bai.

7 recordsLinked to original sources

PubMed2005

[Study on the knowledge of and attitude to sexual dysfunction in aged men].

OBJECTIVE: To investigate the knowledge of and attitude to sexual dysfunction in aged men, and to discuss the status and needs of male healthcare. METHODS: Two thousand seven hundred and twenty-eight men (40-70 years old) were surveyed on sexual dysfunction using the randomized questionnaire in Xicheng District, Beijing. RESULTS: The prevalence of erectile dysfunction (ED) was 41.2%, and only 12.1% ED patients were to see the doctor. 52.4% aged men thought the sexual life was important or very important during the life, and 55.6% thought ED would exert negative impact on the quality of life and the partner relationship. Although 27.4% knew that ED was a kind of disease, 49.0% thought ED was a nature rule. Compare to the 41.2% ED prevalence, only 9.7% male were dissatisfied with their sexual life, and later ratio was 14.1% among the partner. CONCLUSION: In China, the status of the knowledge of and attitude to sexual dysfunction in aged men was unsatisfactory to some extent. There is a lot of work to do especially in sexual healthcare education and improvement on diagnostic and treatment of sexual dysfunction.

Adult↗

PubMed2004

Refolding and purification of interferon-gamma in industry by hydrophobic interaction chromatography.

A new technology for renaturation with simultaneous purification of the recombinant human interferon-gamma (rhIFN-gamma) in downstream of biotechnology is presented. The strategies to develop the new technology in industry scale were suggested. Based on chemical equilibrium and molecular interactions, the principle of rhIFN-gamma refolding by HPHIC was described. The kind of stationary and mobile phases were evaluated and found the former to contribute to the rhIFN-gamma refolding more than the latter. The extract containing the rhIFN-gamma in gram scale in 7.0 mol L(-1) guanidine hydrochloride solution of 700 mL was directly pumped into a unit of simultaneous renaturation and purification of proteins (USRPP, 10 x 300 mm i.d.) packed by small particle packings of hydrophobic interaction chromatography and a satisfactory recovery of bioactivity and mass of the rhIFN-gamma was obtained. With flow rate 100 mL min(-1) and a gradient elution by only one step in 4h, the purity and specific bioactivity approach to 95% and 8.7 x 10(7) IU(-1) mg, respectively. To evaluate the goodness of the presented new technology in this study, a usual method with the renaturation by dilution method firstly and then purification with a series of LC in literature was employed to compare with each other. The obtained result in terms of purity, recoveries of mass and bioactivity, cost time as well as expenses, the former is much better than the latter. Comparing the total bioactivity of rhIFN-gamma in the extract before to that after the renaturation by the USRPP, the total bioactivity of rhIFN-gamma increased 62-fold.

Biotechnology↗

PubMed2004

[How chronic prostatitis affects plasminogen activator system].

OBJECTIVE: To elucidate how chronic prostatitis affects the expression and activity of the plasminogen activator (PA) system and relates to male infertility. METHODS: Twenty-three normal fertile males and 80 chronic prostatitis patients (40 fertile and 40 infertile) were included in this research. SDS polyacrylamide gel electrophoresis and fibrin overlay method were used to estimate the total PA, and tissue PA (tPA), urokinase type PA (uPA) in semen. RESULTS: Total PA, tPA and uPA highly expressed in normal males, but decreased in the semen of the chronic prostatitis patients of both the fertile and infertile groups. However, there was no significant difference in total PA between the fertile and infertile patients. CONCLUSION: Chronic prostatitis reduces the secretory function and PA synthesis and secretion of the prostate, but the decrease of PA alone does not cause infertility. PA may be one of the tools for estimating the function of the prostate.

Adult↗

PubMed2004

Prevalence and risk factors of erectile dysfunction in three cities of China: a community-based study.

AIM: To determine the age-adjusted prevalence of erectile dysfunction (ED) in 3 big cities of China and to explore its potential sociodemographic, medical and lifestyle correlates. METHODS: A cross-sectional, population-based survey was conducted in three cities of China. Structured questionnaires were administered to 2 226 men, aged 20 - 86 years, by trained interviewers. RESULTS: The age-adjusted prevalence of ED was 28.34 % (mild 15.99 %, moderate 7.14 %, severe 5.21 %). In the men above 40, the prevalence was 40.2 %. Age was positively correlated with ED (P<0.01). Education was negatively correlated with ED (P<0.01). Spouse companionship, living condition were positively correlated with ED (P<0.01). Histories of cardiovascular disease, diabetes, and hyperlipidemia were positively correlated with ED (P<0.01). Cigarette smoking was not correlated with ED (P>0.05), while the cigarette consumption and duration were positively correlated with ED (P<0.01). Alcohol drinking is negatively correlated with ED (P<0.01). The duration of drinking was positively correlated with ED (P<0.01). Weekly alcohol consumption was not correlated with ED (P>0.05). CONCLUSION: The prevalence of ED increased with age. Cardiovascular disease, diabetes and hyperlipidemia were positively correlated with the increased prevalence. Sociodemographic and lifestyle factors, such as education, spouse companionship, living condition, cigarette and alcohol consumption or duration also have association with the prevalence of ED.

Adult↗

PubMed2004

Design and resolution of a simple-type column for renaturation with simultaneous purification of proteins and its application to lysozyme refolding.

A new kind of column called simple-type chromatographic column using the packings of large particles, which resembles columns used in traditional low pressure liquid chromatography in both shape and operation but has resolution of biopolymers similar to high performance liquid chromatography, was designed and investigated. In addition, so long as a suitable stationary phase, such as hydrophobic interaction chromatographic stationary phase, is packed, the column can be employed for the purification with simultaneous renaturation of proteins. The structure, operation and characteristics of the designed column including pressure drop, column life, and resolution were investigated. Lysozyme was selected as the model protein for investigating the renaturation. The recoveries of mass and bioactivity were found to be (96.6 +/- 1.3)% and (101.1 +/- 6.0)% respectively when the original concentration of lysozyme was 50.0 g/L. The simple-type column is very cheap and easy to use, and can be applied to the purification of proteins under the condition of low pressure. Thus, it has great potential applications for the purification and/or renaturation of proteins in large scale, down-stream processing of therapeutic proteins in biotechnology.

Chromatography, High Pressure Liquid↗

PubMed2004

A fast method for preparation of cytochrome-C of high purity from pig heart by hydrophobic interaction chromatography.

A fast method for the preparation of cytochrome C (Cyt-C) of high purity from pig heart is presented. A simple-type column of hydrophobic interaction chromatography packed with big particles was employed for the fast purification in laboratory scale. The purity of the purified Cyt-C was verified by reversed-phase liquid chromatography, UV spectroscopy, and iron content in it. Compared with the common method, the new method has advantages of higher speed, simpler purification processes, higher mass recoveries and higher purity.

Animals↗

PubMed2002

[Characterization of chromatographic behavior of polar solutes of small molecules with lgI in reversed-phase liquid chromatography].

A new characterization parameter lgI, affinity constant, in reversed-phase liquid chromatography (RPLC) has been tested at several aspects with experimental data of polar n-alkyl alcohol homologoues and aromatic alcohol homologoues. The lgI values were compared with other physicochemical parameters of corresponding solutes, such as hydrophobic fragmental constant (lgf), van der Waals volume (Vw), molecular connectivity (chi). It was proved that lgI was also used for the characterization of solutes, mobile and stationary phases in RPLC. Moreover, it was also confirmed that lgI has the property of thermodynamic equilibriam constant.

Chemical Phenomena↗