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Biomedicine
DNA-damage response network at the crossroads of cell-cycle checkpoints, cellular senescence and apoptosis
SCHMITT Estelle, PAQUET Claudie, BEAUCHEMIN Myriam, BERTRAND Richard
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(6): 377-397.   https://doi.org/10.1631/jzus.2007.B0377
Abstract( 4365 )     PDF(0KB)( 2012 )
Tissue homeostasis requires a carefully-orchestrated balance between cell proliferation, cellular senescence and cell death. Cells proliferate through a cell cycle that is tightly regulated by cyclin-dependent kinase activities. Cellular senescence is a safeguard program limiting the proliferative competence of cells in living organisms. Apoptosis eliminates unwanted cells by the coordinated activity of gene products that regulate and effect cell death. The intimate link between the cell cycle, cellular senescence, apoptosis regulation, cancer development and tumor responses to cancer treatment has become eminently apparent. Extensive research on tumor suppressor genes, oncogenes, the cell cycle and apoptosis regulatory genes has revealed how the DNA damage-sensing and -signaling pathways, referred to as the DNA-damage response network, are tied to cell proliferation, cell-cycle arrest, cellular senescence and apoptosis. DNA-damage responses are complex, involving “sensor” proteins that sense the damage, and transmit signals to “transducer” proteins, which, in turn, convey the signals to numerous “effector” proteins implicated in specific cellular pathways, including DNA repair mechanisms, cell-cycle checkpoints, cellular senescence and apoptosis. The Bcl-2 family of proteins stands among the most crucial regulators of apoptosis and performs vital functions in deciding whether a cell will live or die after cancer chemotherapy and irradiation. In addition, several studies have now revealed that members of the Bcl-2 family also interface with the cell cycle, DNA repair/recombination and cellular senescence, effects that are generally distinct from their function in apoptosis. In this review, we report progress in understanding the molecular networks that regulate cell-cycle checkpoints, cellular senescence and apoptosis after DNA damage, and discuss the influence of some Bcl-2 family members on cell-cycle checkpoint regulation.
Lipids changes in liver cancer
JIANG Jing-ting, XU Ning, ZHANG Xiao-ying, WU Chang-ping
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(6): 398-409.   https://doi.org/10.1631/jzus.2007.B0398
Abstract( 2552 )     PDF(0KB)( 1463 )
Liver is one of the most important organs in energy metabolism. Most plasma apolipoproteins and endogenous lipids and lipoproteins are synthesized in the liver. It depends on the integrity of liver cellular function, which ensures homeostasis of lipid and lipoprotein metabolism. When liver cancer occurs, these processes are impaired and the plasma lipid and lipoprotein patterns may be changed. Liver cancer is the fifth common malignant tumor worldwide, and is closely related to the infections of hepatitis B virus (HBV) and hepatitis C virus (HCV). HBV and HCV infections are quite common in China and other Southeast Asian countries. In addition, liver cancer is often followed by a procession of chronic hepatitis or cirrhosis, so that hepatic function is damaged obviously on these bases, which may significantly influence lipid and lipoprotein metabolism in vivo. In this review we summarize the clinical significance of lipid and lipoprotein metabolism under liver cancer.
Experiences and benefits of positron emitted tomography-computed tomography (PET-CT) combined with video-assisted thoracoscopic surgery (VATS) in the diagnosis of Stage 1 sarcoidosis
LUH Shi-ping, WU Tzu-chin, WANG Yao-tung, TSAO Thomas Chang-yao, CHEN Jia-yuh
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(6): 410-415.   https://doi.org/10.1631/jzus.2007.B0410
Abstract( 2680 )     PDF(0KB)( 1417 )
Background: The purpose of this study was to describe our experiences and analyze the benefits of video-assisted thoracoscopic surgery (VATS) combined with positron emitted tomography (PET)-computed tomography (CT) in the diagnosis of patients with early (Stage 1) sarcoidosis. Methods: From 1995 to 2006, seven patients (two males, five females), with ages ranging from 26 to 58 years, were impressed with Stage 1 sarcoidosis (mediastinal or hilar lymph nodes involvements without lung involvement) by histological examination of intrathoracic lymph nodes (LNs) and/or lung parenchyma taken from VATS biopsy. Three of them received PET or PET-CT evaluation. VATS was approached from the right and left side in one and six patients, respectively, according to the locations of their lesions. Results: All the VATS biopsied LNs or lung specimens were adequate for establishing diagnosis. Mediastinal LNs were taken from Groups 3, 4 in four, Group 7 in two, and Groups 5, 6 in one of them. Hilar LNs biopsies were performed in four cases. Lung biopsy was performed in all but two cases. All of them were expressed pathologically or radiologically as Stage 1 sarcoidosis. PET-CT revealed high emission signals over these affected LNs. These patients received oral steroid treatment or follow up only. All of them were followed up from 5 months to 11 years with satisfactory results. Conclusion: VATS biopsy is a minimally invasive, safe and effective procedure. It can be used as a diagnostic alternative of transbronchial lung biopsy (TBLB), and can harvest larger and more areas of specimens than mediastinoscopy for staging patients with sarcoidosis. PET-CT can provide us more accurate information about the characteristics and localization of these lesions before biopsy. VATS combined with PET-CT can provide more accurate and earlier diagnosis of patients with unknown intrathoracic lesions, including the sarcoidosis.
Stabilization of an abutment under a rigidly fixed bridge by holographical-speckle interferometry
ZHANG Yan-zhen, ZHOU Yan-chun, LIU Li, LU Yang, HIROFUMI Yatani
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(6): 416-421.   https://doi.org/10.1631/jzus.2007.B0416
Abstract( 2126 )     PDF(0KB)( 1593 )
Objective: There are no detailed reports of three-dimensional measurement of abutment teeth in mastication, because it is knotty to observe the rotation in chewing directly, and inexact to estimate indirectly. This work studies the three-dimensional stability of rigidly fixed bridge under the stresses of distributed loads and concentrated loads by optical method that gives the tip angle and rotation angle calculated directly based on measurement data. Methods: The specimen, taken from a 25-year-old male, was a left mandible without the second premolars and the first molars. As abutments, first premolar and second molar have complete periodontium. The specimen was soaked in formaldehyde solution. The bridge was fixed between two abutment teeth (first premolars and second molars), and the mandible was cemented in a steel box. The load was increased from 0 kg to 23 kg. Laser holographic technique was used to measure the three-dimensional bit shift of the dens, both buccolingual bit shift and mesiodistal bit shift, and determine tip angle and rotation angle. Results: The effects of stress distribution on the rigidly fixed bridge were evaluated, and stabilization of the bridge under the stresses of distributed loads and concentrated loads, respectively, were analyzed. The results showed that the tips of two abutments were very similar, and no distinct difference was observed between the distributed load and the concentrated load. However, the maximum rotation angle for the distributed load was two to four times as large as that for the concentrated load. In the experiment, the tip angle of the abutment teeth was no more than 0.65 degree, and the rotation angle was no more than 0.60 degree. All maximum angles occurred in the second molar. Conclusion: The fixed bridge is considered to be safe. In addition, a method for measuring the rotation angle was provided effectively.
Effect of lead on ERK activity and the protective function of bFGF in rat primary culture astroglia
ZHANG Ying, YE Li-ping, WANG Biao, CAO Shi-cheng, SUN Li-guang
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(6): 422-427.   https://doi.org/10.1631/jzus.2007.B0422
Abstract( 2680 )     PDF(0KB)( 1337 )
Objective: To observe the effects of lead on levels of phosphorylated extracellular signal regulated kinase (p-ERK) in the cytoplasm of primary cultures of rat astroglial cells and the possible protective effect of basic fibroblast growth factor (bFGF) on lead-induced effects. Methods: The primary astroglia cells from 1~6 d old Wistar rats were cultured. The cells pretreated with the MEK1 (mitogen-activated protein kinase kinase 1) inhibitor PD98059 and bFGF, respectively, were exposed to Pb acetate of different concentrations for different times. Western blotting and reverse transcription polymerase chain reaction (RT-PCR) methods were used to detect the protein and mRNA expressions of ERK. Results: mRNA expression for ERK peaked 15 min after initiation of lead exposure (P<0.05) and protein expression of p-ERK peaked at 30 min (P<0.05). ERK mRNA levels and p-ERK protein levels returned to baseline after 60 and 120 min of lead exposure, respectively (P>0.05). The increase in p-ERK levels in lead-treated cells could be inhibited by PD098059. Activation of ERK in the cells by lead was prevented by pretreatment with bFGF. Total ERK protein levels did not change under the same experimental conditions (P>0.05). Conclusion: Low-level lead exposure resulted in transient activation of ERK through the MEK pathway, which then returned to basal levels in the continued presence of lead. Exogenous bFGF protected ERK signaling components in astroglia from lead poisoning.
Comparison of 1.5% lidocaine and 0.5% ropivacaine epidural anesthesia combined with propofol general anesthesia guided by bispectral index
XIANG Yan, LI Yu-hong
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(6): 428-434.   https://doi.org/10.1631/jzus.2007.B0428
Abstract( 2515 )     PDF(0KB)( 1423 )
Objective: To compare the effects of epidural anesthesia with 1.5% lidocaine and 0.5% ropivacaine on propofol requirements, the time to loss of consciousness (LOC), effect-site propofol concentrations, and the hemodynamic variables during induction of general anesthesia guided by bispectral index (BIS) were studied. Methods: Forty-five patients were divided into three groups to receive epidurally administered saline (Group S), 1.5% (w/w) lidocaine (Group L), or 0.5% (w/w) ropivacaine (Group R). Propofol infusion was started to produce blood concentration of 4 μg/ml. Once the BIS value reached 40~50, endotracheal intubation was facilitated by 0.1 mg/kg vecuronium. Measurements included the time to LOC, effect-site propofol concentrations, total propofol dose, mean arterial blood pressure (MABP), and heart rate (HR) at different study time points. Results: During induction of anesthesia, both Groups L and R were similar for the time to LOC, effect-site propofol concentrations, total propofol dose, MABP, HR, and BIS. The total doses of propofol administered until 1 min post-intubation were significantly less in patients of Groups R and L compared with Group S. MABP and HR were significantly lower following propofol induction compared with baseline values in the three groups, or MABP was significantly increased following intubation as compared with that prior to intubation in Group S but not in Groups R and L while HR was significantly increased following intubation in the three groups. Conclusion: Epidural anesthesia with 1.5% lidocaine and 0.5% ropivacaine has similar effects on the time to LOC, effect-site propofol concentrations, total propofol dose, and the hemodynamic variables during induction of general anesthesia.
Diagnosis and treatment of pheochromocytoma in urinary bladder
LIU Yong, DONG Sheng-guo, DONG Zhen, MAO Xin, SHI Xin-yan
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(6): 435-438.   https://doi.org/10.1631/jzus.2007.B0435
Abstract( 2627 )     PDF(0KB)( 1287 )
Objective: To study the diagnosis and treatment of pheochromocytoma in urinary bladder. Methods: Six cases of bladder pheochromocytoma were studied. Four cases showed hypertension, 3 of which were paroxysmal hypertension during urination. Catecholamine (CA) was increased in a case, and vanillymandelic acid (VMA) was increased in 2 cases. Bladder submucosal mass was detected by B-ultrasound in 5 cases (5/5), computerized tomography (CT) in 3 cases (3/3), cystoscopy in 5 cases (5/6). Four cases took α-receptor blocker for 2 weeks, 1 case took β-receptor blocker to decrease heart rate. All patients were treated with surgical operation including 4 partial cystectomies, 2 excavations. Results: Three cases had manifestations including headache, excessive perspiration and hypertension during cystoscopy. Four cases were confirmed before operation. Two cases showed hypertension during operation. All patients were pathologically diagnosed as pheochromocytoma postoperatively. In five cases followed up, blood pressure returned to normal. No patient had relapse and malignancy. Conclusions: Typical hypertension during urination comprised the main symptoms. We should highly suspect bladder pheochromocytoma if a submucosal mass was discovered with B-ultrasound, CT, 131I-MIBG (methyliodobenzylguanidine) and cystoscopy. The determination of CA in urine is valuable for qualitative diagnosis. The preoperative management of controlling blood pressure and expansion of the blood volume are very important. Surgical operation is a good method for effective treatment. Postoperative long-time followed up is necessary.
Pharmaceutical Sciences
Investigation on influencing factors of 5-HMF content in Schisandra
XU Qing, LI Ying-hua, LÜ Xiu-yang
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(6): 439-445.   https://doi.org/10.1631/jzus.2007.B0439
Abstract( 2593 )     PDF(0KB)( 1478 )
In order to investigate the influencing factors of 5-hydroxymethyl-2-furaldehyde (5-HMF) content in Schisandra, confirm the theory of 5-HMF deriving mainly from Schisandra processing course, and give some suggestions about the Schisandra processing method, the 5-HMF contents in decoctions of Schisandra under different heating temperature, decocting time, soaking time, processing methods and treatment with different solvents before decocting the Schisandra were measured by RP-HPLC method. The results showed that there is great difference of 5-HMF level in decoctions from differently processed Schisandra and unprocessed Schisandra; decocting time of 60 min has some effects on 5-HMF level in decoctions and there is certain quantity 5-HMF in processed Schisandra itself and very little 5-HMF in unprocessed Schisandra. Heating time, heating temperature and treating solvents all have effect on 5-HMF level in decoction of Schisandra. 5-HMF in Schisandra was mainly from processing course. Both long heating time and high heating temperature can increase 5-HMF level in Schisandra. The production of 5-HMF in Schisandra may have some relationships with some polar components, which can dissolve in water, ethanol and acetone, especially in ethanol. To control processing temperature, processing time and treatment with some solvent is very important for controlling 5-HMF level in Schisandra.
Synthesis of Schiff bases of naphtha[1,2-d]thiazol-2-amine and metal complexes of 2-(2'-hydroxy)benzylideneaminonaphthothiazole as potential antimicrobial agents
AZAM Faizul, SINGH Satendra, KHOKHRA Sukhbir Lal, PRAKASH Om
Journal of Zhejiang University-SCIENCE B (Biomedicine & Biotechnology), 2007, 8(6): 446-452.   https://doi.org/10.1631/jzus.2007.B0446
Abstract( 2763 )     PDF(0KB)( 1673 )
Objective: A series of 2-benzylideneaminonaphthothiazoles were designed and synthesized incorporating the lipophilic naphthalene ring to render them more capable of penetrating various biomembranes. Methods: Schiff bases were synthesized by the reaction of naphtha[1,2-d]thiazol-2-amine with various substituted aromatic aldehydes. 2-(2'-Hydroxy)benzylideneaminonaphthothiazole was converted to its Co(II), Ni(II) and Cu(II) metal complexes upon treatment with metal salts in ethanol. All the compounds were evaluated for their antibacterial activities by paper disc diffusion method with Gram positive Staphylococcus aureus and Staphylococcus epidermidis and Gram negative Escherichia coli and Pseudomonas aeruginosa bacteria. The minimum inhibitory concentrations of all the Schiff bases and metal complexes were determined by agar streak dilution method. Results: All the compounds moderately inhibited the growth of Gram positive and Gram negative bacteria. In the present study among all Schiff bases 2-(2'-hydroxy)benzylideneaminonaphthothiazole showed maximum inhibitory activity and among metal complexes Cu(II) metal complex was found to be most potent. Conclusion: The results obtained validate the hypothesis that Schiff bases having substitution with halogens, hydroxyl group and nitro group at phenyl ring are required for the antibacterial activity while methoxy group at different positions in the aromatic ring has minimal role in the inhibitory activity. The results also indicated that the metal complexes are better antibacterial agents as compared to the Schiff bases.
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