1.How does transmembrane electrochemical potential drive the rotation of Fo motor in an ATP synthase?
Xuejun C ZHANG ; Min LIU ; Yan ZHAO
Protein & Cell 2015;6(11):784-791
While the field of ATP synthase research has a long history filled with landmark discoveries, recent structural works provide us with important insights into the mechanisms that links the proton movement with the rotation of the Fo motor. Here, we propose a mechanism of unidirectional rotation of the Fo complex, which is in agreement with these new structural insights as well as our more general ΔΨ-driving hypothesis of membrane proteins: A proton path in the rotor-stator interface is formed dynamically in concert with the rotation of the Fo rotor. The trajectory of the proton viewed in the reference system of the rotor (R-path) must lag behind that of the stator (S-path). The proton moves from a higher energy site to a lower site following both trajectories simultaneously. The two trajectories meet each other at the transient proton-binding site, resulting in a relative rotation between the rotor and stator. The kinetic energy of protons gained from ΔΨ is transferred to the c-ring as the protons are captured sequentially by the binding sites along the proton path, thus driving the unidirectional rotation of the c-ring. Our ΔΨ-driving hypothesis on Fo motor is an attempt to unveil the robust mechanism of energy conversion in the highly conserved, ubiquitously expressed rotary ATP synthases.
Membrane Potentials
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physiology
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Membrane Proteins
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chemistry
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metabolism
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Mitochondrial Proton-Translocating ATPases
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chemistry
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metabolism
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Protein Conformation
2.Screening on serum biomarkers in idiopathic pulmonary fibrosis patients by proteomics technology.
Chinese Journal of Epidemiology 2018;39(8):1117-1120
Objective: Applying the proteomics technology to identify proteins differentially in serums of idiopathic pulmonary fibrosis patients and normal population. Methods: The study included serum samples from idiopathic pulmonary fibrosis group and normal controlled group with 30 cases of each, from the Second Hospital of Shandong University, between October 2014 and October 2015. Proteins differentially expressed in serums were quantified by the isobaric tags for relative and absolute quantization coupled with two-dimensional liquid chromatography/tandem mass spectrometry technology. The proteins were analyzed in terms of molecular function, cell location and biological processes for showing the key protein molecules which were related to the development of idiopathic pulmonary fibrosis. Results: A total of 490 kinds of proteins (with confidence coefficient above 95%) were identified by mass spectrometry and 25 kinds of differentially expressed proteins were found. Compared with the control group, we found 4 types of up-regulated proteins and 21 down-regulated ones in the serum of idiopathic pulmonary fibrosis patients. Data from the Gene ontology analysis showed that most differentially expressed proteins were in the extracellular region (92%) while pathway enrichment analysis showed that most proteins were involved in the complement and coagulation cascade pathway. Conclusion: Proteins related to the complement system coagulation cascade pathway, and the proteins function need to be further studied.
Biomarkers/metabolism*
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Blood Proteins/metabolism*
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Chromatography, Liquid/methods*
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Humans
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Idiopathic Pulmonary Fibrosis/metabolism*
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Proteins/metabolism*
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Proteomics/methods*
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Tandem Mass Spectrometry/methods*
3.Effect of naringenin on NaIO3-induced retinal pigment epithelium degeneration and laser-induced choroidal neovascularization in rats
Yi, SHEN ; Wan-Yu, ZHANG ; George C Y CHIOU
International Eye Science 2010;10(1):1-4
AIM: To study the effects of naringenin eye drops on NaIO3-induced retinal pigment epithelium (RPE) degeneration and laser-induced choroidal neovascularization (CNV) in rat eyes.METHODS: The 35mg/kg NaIO3-induced RPE degeneration was prevented by 10g/L naringenin eye drops 3 times a day for 7 days in advance of NaIO3 injection, and then 2 to 4 weeks thereafter, RPE function was measured with C-wave of electroretinogram (ERG). The laser-induced CNV rats were treated with laser to break the Bruchs membrane and the CNV formation was prevented by 10g/L naringenin eye drops instilled 3 times a day for 2 to 4 weeks. The CNV formation was measured with fluorescein angiography (FA) and flat mount. RESULTS: Two weeks after NaIO3 injection, the amplitude of ERG C-wave fell markedly in NaIO3 group to 53% of normal group (P<0.01). No apparent difference was observed in naringenin+ NaIO3 group. Four weeks later, the NaIO3 group fell to 37% of normal group (P<0.01), while the naringenin+ NaIO3 group fell to only 57% of normal group (P<0.01). There is a 52% reversal of the ERG C-wave by naringenin as compared to NaIO3 treated group (P<0.05). Two weeks and four weeks after laser treatment, naringenin reduced the CNV formation to 53% and 49% of control group (100%) measured by FA (P<0.01). Four weeks after laser treatment, naringenin reduced the CNV formation by 47% as compared to control group measured with flat mount (P<0.01).CONCLUSION: Naringenin significantly protected RPE from NaIO3 induced degeneration and can also prevent CNV formation.
4.Effects of hydralazine on NaIO3-induced rat retinal pigment epithelium degeneration
Wei, JIANG ; Wan-Yu, ZHANG ; George C Y CHIOU
International Eye Science 2008;8(8):1504-1510
·AIM: To study the effects of 10g/L hydralazine eye drops on 35mg/kg NaIO3-induced degeneration in rat eyes. · METHODS: Various doses of NalO3 and/or saline alone were injected into Brown Norway rats from hypoglossal vein. After 3, 7, 14 or 28 days of injection, ERG a-, b-, c- wave, fast oscillation (FO) and light peak (LP) were measured along with retinal colored pictures and fluorescein angiography taken. Some rats were chosen to study the histology of retinas by light microscopy and autofluorescence of retina flatmounts. Different concen- trations of NaIO3 were given to RPE-19 cells, and cell proliferation rate was measured. For hydralazine study, 35mg/kg NaIO3 was injected into Brown Norway rat from hypoglossal vein. NaIO3 group was treated with saline alone after NaIO3 injection, 10g/L hydralazine + NaIO3 group was treated with 10g/L hydralazine eyedrops after NaIO3 injection whereas normal group was treated with saline alone without NalO3 injection. All eyedrops were instilled locally 3 times a day for 4 weeks and ERG c-wave was measured at the end of 2 and 4 weeks.· RESULTS: After NaIO3 administration, the amplitude of all ERG waves fell markedly in large dose groups at 30, 40 or 60mg/kg NaIO3. Not many changes were observed in groups treated with < 30mg/kg NaIO3. Some retinal necrosis appeared from 3 days post-injection (PI) in 30mg/kg NaIO3 group, which became more serious in larger dose groups or longer treatment time, but no apparent change was found in smaller dose groups. Similarly, on the retina flatmount, RPE monolayer showed necrosis from 3 days PI in the 30mg/kg NaIO3 and larger dose groups. On histological examination, no significant change was seen in 30mg/kg NaIO3 and lower concentration groups. In cell culture experiment, changes were found in RPE-19 cells proliferation rate with a concentration of NaIO3 at 30mg/L or higher. In hydralazine experiments, 4 weeks after injection of NaIO3, ERG c-wave fell markedly in NaIO3 group to 31% of control group (P < 0.01). The ERG c-wave of hydra- lazine + NaIO3 group fell only to 50% of control group (P<0.05). This was a 61% reversal of the c-wave of NaIO3 treated group. · CONCLUSION: RPE degeneration induced by NaIO3 was both dose and time dependent. Around 30 to 40 mg/kg NaIO3 would be the optimal to be used as a non-exudative age-related macular degeneration rat model. Hydralazine may postpone the development of non-exudative age- related macular degeneration.
5.X-ray observations on anterior drawer test in rupture of the lateral ligament of the ankle.
Z N Qu YANG ; C R YANG ; T Q ZHANG
Chinese Journal of Surgery 1985;23(4):215-254
Adolescent
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Adult
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Ankle Injuries
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Ankle Joint
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diagnostic imaging
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Female
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Humans
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Ligaments, Articular
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diagnostic imaging
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injuries
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Male
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Middle Aged
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Radiography
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Rupture
7.Study on the salt-processing technology of Rosa laevigata and its HPLC fingerprints and chromaticity values before and after salt-processing
Hongtao ZHANG ; Jing ZHANG ; Lingxu MENG ; Zhenghua ZHU ; Xiangjun MENG ; Xiaohuan ZHANG
China Pharmacy 2022;33(7):861-866
OBJECTIV E To optimize the s alt-processing technology of Rosa laevigata ,and to study high performance liquid chromatography(HPLC)fingerprints and chromaticity values of R. laevigata before and after salt-processing. METHODS The comprehensive scoring method was adopted to optimize the salt-processing technology of R. laevigata using appearance character , moisture and polysaccharide content as index. Fingerprints were established by HPLC method before and after salt-processing ,and chromaticity values (L*,a*,b*)of the powder before and after salt-processing were determined. The multivariate statistical analysis was carried out for raw product and salt-processing product of R. laevigata by using common peak areas and chromaticity values as index. RESULTS The optimal salt-processing technology of R. laevigata was to mix it with appropriate amount of salt water ,place them in the preheated frying wok at 140 ℃,fry them for 25 min,and rotate frying wok 20 times/min. Ten common peaks were calibrated by HPLC fingerprints before and after salt-processing ,and 3 components were identified ,such as gallic acid ,catechin and ellagic acid. The chromaticity values L*,b* and E* changed significantly after salt-processing. The multivariate statistical analysis method could distinguish raw products and salt-processing products into two categories ,in which peaks 1,5,6 and 10 and chromaticity values b* and E* were important characteristic factors. CONCLUSIONS The optimized salt-processing technology is stable and reliable ,and the established fingerprint has good repeatability and stability. Fingerprint and chromaticity values combined with multivariate statistical analysis can provide reference for the identification and quality analysis of R. laevigata before and after salt-processing.
8.Prevalence, awareness, treatment and control of hypertension in population older than 15 years of age in Beijing, 2013-2014.
C X WANG ; X G WU ; H J LIU ; S C GUAN ; C B HOU ; H H LI ; X GU ; Z Y ZHANG ; X H FANG
Chinese Journal of Epidemiology 2018;39(2):179-183
Objective: To investigate the rates on prevalence, awareness, treatment and control of hypertension in population older than 15 years of age in Beijing, 2013-2014. Methods: A cross-sectional survey was conducted in Beijing between 2013-2014. Stratified multistage random sampling method was used to select representative sample of 13 057 Chinese individuals aged over 15 years, from the general population. Blood pressure was measured for three readings at sitting position after resting for at least five minutes with an average reading recorded. A standardized structured questionnaire was developed to collect history of hypertension and antihypertensive treatment. Results: A total of 4 663 community residents aged over 15 years were hypertensive among the 13 057 individuals, with the standardized prevalence rate as 32.7%, in Beijing area. The age-standardized prevalence rates of hypertension appeared 34.6% in men and 30.8% in women. The age-and sexstandardized prevalence of hypertension rates were 33.3% in urban and 24.6% in rural areas. The prevalence of hypertension increased with age and appeared higher in men than in women, in urban than in rural residents. Among the hypertensive patients, rates of awareness, treatment and control were 66.8%, 64.6% and 31.6%, respectively. Conclusion: High prevalence of hypertension with low rates on awareness and treatment and control, appeared in the general population of Beijing. Related strategies should be developed regarding prevention, control and management of hypertension, to reduce the burden of this disease.
Adolescent
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Adult
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Age Distribution
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Aged
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Antihypertensive Agents/therapeutic use*
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Asian People/statistics & numerical data*
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Awareness
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Blood Pressure
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Blood Pressure Determination
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China/epidemiology*
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Cross-Sectional Studies
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Female
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Health Knowledge, Attitudes, Practice
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Humans
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Hypertension/epidemiology*
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Male
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Middle Aged
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Prevalence
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Rural Population
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Sex Distribution
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Surveys and Questionnaires
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Urban Population
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Young Adult
9.Corticospinal tract degeneration in amyotrophic lateral sclerosis: a diffusion tensor imaging and fibre tractography study.
Hong YIN ; Sandy H T CHENG ; Jian ZHANG ; Lin MA ; Yuangui GAO ; Dejun LI ; C C Tchoyoson LIM
Annals of the Academy of Medicine, Singapore 2008;37(5):411-415
INTRODUCTIONMotor neuron damage and cortical spinal tract (CST) degeneration in amyotrophic lateral sclerosis (ALS) are difficult to visualise and quantify on conventional magnetic resonance imaging (MRI).
CLINICAL PICTUREWe studied 8 ALS patients and 12 normal volunteers using diffusion tensor imaging (DTI) and fibre tractography using fibre assignment by continuous tracking (FACT) to study the fibres of the CST and the posterior thalamic radiation (PTR), a nonmotor tract.
OUTCOMEFibre tractography was successfully performed in all normal volunteers and all patients except 1. The fibre bundles of the CST, but not the PTR, were significantly reduced (P <0.05) in patients compared to normal volunteers.
CONCLUSIONFibre tractography can visualise axonal degeneration in the CST and may provide supplementary information about upper motor neuron disease in ALS patients.
Amyotrophic Lateral Sclerosis ; pathology ; Case-Control Studies ; Diffusion Magnetic Resonance Imaging ; Echo-Planar Imaging ; Female ; Humans ; Male ; Middle Aged ; Nerve Degeneration ; pathology ; Pyramidal Tracts ; pathology
10.Analysis on 10 year survival of HIV/AIDS patients receiving antiretroviral therapy during 2003-2005 in Henan province.
Y SUN ; Q X ZHAO ; C F LI ; X YANG ; X ZHANG ; C L LIU ; Z Y CHEN
Chinese Journal of Epidemiology 2018;39(7):966-970
Objective: To understand the survival of HIV/AIDS patients after receiving antiretroviral therapy for 10 year in Henan province and related factors. Methods: The database of national integrated management system of HIV/AIDS was used to collect the basic information and follow-up information of HIV/AIDS patients who received antiretroviral therapy between 2003 and 2005 in Henan province. Software SPSS 23.0 was used to analyze the patients' survival and related factors based on the life-table method and Cox proportional hazards model. Results: Among the 2 448 HIV/AIDS patients who started antiretroviral therapy during 2003-2005, the men accounted for 53.5%, and women accounted for 46.5%. Up to 70.1% of the patients were aged 40-59 years and 95.5% of the patients had blood borne infections. The patients were observed for 10 years after antiviral treatment, and 719 cases died from AIDS related diseases, with a mortality rate of 3.78/100 per year (719/19 010 per year). The cumulative survival rates of patients within 1-year, 3 years, 5 years and 10 years were 0.94, 0.86, 0.78, 0.69 respectively. Compared with the patients aged <40 years, the HRs of the patients aged 40-, 50-, 60- and ≥70 years were 1.417 (95%CI: 0.903-2.222), 1.834 (95%CI: 1.174-2.866), 2.422 (95%CI: 1.539-3.810) and 3.424 (95%CI: 2.053-5.709) respectively. Compared with patients with baseline CD(4+)T lymphocyte >350 unit/ul, the HRs of the patients with CD(4+)T lymphocyte <50 unit/μl, 50-199 unit/ul and 200-350 unit/ul were 7.105 (95%CI: 5.449-9.264), 4.175 (95%CI: 3.249-5.366) and 2.214 (95%CI: 1.691-2.900) respectively. Compared with the women, the HR of the men was 1.480 (95%CI: 1.273-1.172). Compared with the patients who received second line ART therapy, the HR of patients receiving no second line therapy was 11.923 (95%CI: 9.410-15.104). Conclusions: The cumulative survival rate the HIV/AIDS patients after 10 years of antiretroviral therapy reached 0.69 in Henan. Male, old age, low basic CD(4+)T lymphocyte count and receiving no second line therapy were the risk factors for long-term survival of AIDS patients.
Acquired Immunodeficiency Syndrome
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Adult
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Aged
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Antiretroviral Therapy, Highly Active
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CD4 Lymphocyte Count
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China/epidemiology*
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Female
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HIV/drug effects*
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HIV Infections/mortality*
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Humans
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Male
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Middle Aged
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Proportional Hazards Models
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Risk Factors
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Survival Analysis
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Survival Rate