RT-PCR and in situ hybridization were observed during dialyzer reuse. Results Every plasma cytokine level was decreased during reuse compared with first use dialyzer, but no significant difference was found between them. The levels of gene expression of IL-1?、TNF-? and IL-6 were different from the first use significantly. Conclusion If effective dialysis volumn was maintained, formaldehyde as disinfectant on reprocessing the dialyzer may amilorate membrane bio-compatibility. It would be benificial to decrease appearance of long term hemodialysis -related complications.

Objective To investigate the morphological changes of peritoneum during peritoneal dialysis (PD) and elucidate the possible mechanism of its functional deterioration. Methods Peritoneal biopsies were obtained from normal subjects( n = 10), uremic predialysis patients( n = 12) at catheter insertion and PD patients ( n = 10) at the time of catheter remove or reinsertion or renal transplantation, peritoneal morphology was studied by light microscopy, scanning electron microscopy and transmission electron microscopy. Results Normal peritoneal membrane consisted of a monolayer of mesothelial cells on a basement membrane, and a layer of connective tissue containing cells, blood vessels, lymphatic vessels and so on. Mesothelial cells were polygonal, often elongated, and had numerous microvilli on their luminal surface. Sometimes the microvilli ended with roundish formation or resembled a corona. There were lots of oval or roundish pinocytotic vesicles in the cytoplasm of mesothelial cell. Submesothelial connective tissue contained many collagen and elastic fibers. The peritoneal morphology of uremic predialysis patients was similar to that of normal subjects. But significant abnormalities of peritoneal morphology were observed in PD patients and the changes were progressive. Microvilli were the first site of damage, including microvilli shortening, gradual reduction in number and following total disappearance. Then mesolhelial cell detachment from basement membrane and total disappearances were found. Finally the peritoneal membrane only consisted of submesothelial connective tissue denudation of cells. Conclusions PD can modify peritoneal morphology and structure. The morphological change is progressive and might be one of the important causes of peritoneal failure. Peritoneal biopsy can provide lots of valuable informations about the impact of PD, and thus further study on the relationship between peritoneal structure and its function is very useful for understanding of the physiopathology of peritoneum during PD.

The AC impedance of human hepatoma SMMC-7721 cells were measured in our laboratory by Agilent 4294A impedance analyzer in the frequency range of 0.01-100 MHz. And then the effect of hematocrit on electrical impedance characteristics of hepatoma cells was observed by electrical impedance spectroscopy, Bode diagram, Nyquist diagram and Nichols diagram. The results showed that firstly, there is a frequency dependence, i.e., the increment of real part and the imaginary part of complex electrical impedance (δZ', δZ"), the increment of the amplitude modulus of complex electrical impedance (δ[Z *]) and phase angle (δθ) were all changed with the increasing frequency. Secondly, it showed cell volume fraction (CVF) dependence, i. e. , the increment of low-frequency limit (δZ'0, δ[Z*] 0), peak (δZ"(p), δθ(p)), area and radius (Nyquist diagram, Nichols diagram) were all increased along with the electric field frequency. Thirdly, there was the presence of two characteristic frequencies: the first characteristic frequency (f(c1)) and the second characteristic frequency (f(c2)), which were originated respectively in the polarization effects of two interfaces that the cell membrane and extracellular fluid, cell membrane and cytoplasm. A conclusion can be drawn that the electrical impedance spectroscopy is able to be used to observe the electrical characteristics of human hepatoma cells, and therefore this method can be used to investigate the electrophysiological mechanisms of liver cancer cells, and provide research tools and observation parameters, and it also has important theoretical value and potential applications for screening anticancer drugs.
Carcinoma, Hepatocellular ; Cell Line, Tumor ; Cell Membrane ; Cytoplasm ; Electric Impedance ; Electrophysiological Phenomena ; Humans ; Liver Neoplasms ; Membrane Potentials

Objective To investigate the functional and ultrastructural changes of cerebral microvascular endothelial cells at early stage following traumatic brain injury (TBI) in rats. Methods The rat models with closed brain injury were established with the improved Marmarous method. The expressions of thrombomodulin (TM) and von Willebrand factor (vWF) were determined by immunohistochemical techniques (5 rats per group) and real-time quantitative RT-PCR (5 rats per group) respectively at 1, 4, 8, 12, 24 hours and at days 3 and 7 after injury. Results TM and vWF started expression at 4 hours, reached peak at 24 hours and recovered to normal at day 7 after TBI. The expression levels of TM and vWF at different time points in sham control group showed statistical difference compared with damage group (P < 0.05). Conclusion The activation of the cerebral microvascular endothelial cells at early stage after TBI is the main mechanism of early secondary brain injury.

To determine whether uremia per se can activate peripheral blood mononuclear cells (PBMCs). Methods Maintained hemodialysis patients with cuprophane, non-dialysis uremic patients and healthy volunteers were selected to investigate IL-1?、 TNF-? and 11,6 mRNA in PBMCs by RT-PCR and cells in situ hybridization. Results IL-1?,TNF-? and IL-6 mRNA in PBMCs were undetected in healthy volunteers, but these cytokine gene expression were detected in hemodialysis patients and non-dialysis uremic patients. IL-1?、TNF-? and IL-6 mRNA level was lower in non-dialysis uremic patients than that in hemodialysis patients. Conclusion Uremia per se or its related factors may activated PBMCs and the preactivation of PBMCs might be associated with the body resistance against infection in uremic patients.

Objective: To investigate the value of double source CT(DSCT)in the diagnosis of myocardial bridge(MB)and analyze the correlation of MB-associated coronary atherosclerotic plaque with age.Methods: A total of 417 patients suspected of coronary artery disease(CAD)were divided into a young group(n=137,30-44 yrs),a middle-aged group(n=197,45-59 yrs) and an old group(n=83,60-84 yrs),subjected to DSCT coronary angiography,and analyzed for the differences in the incidence of MB and coronary atherosclerosis.Results: Altogether 76 cases(18.2%) were diagnosed as MB,10(13.2%) in the young,36(47.4%) in the middle-aged and 30(39.5%) in the old group.Of the MB patients,41(53.9%) were complicated with coronary atherosclerotic plaque,2(20.0%) in the young,17(47.2%) in the middle-aged 22(73.3%) in the old group.There were significant statistical differences in the incidence and the nature of coronary atherosclerotic plaque among the 3 groups(P

Objective To compare the effects of different ischemic preconditioning (IP) protocols on the viability of primary cultured sinoatrial node cells from neonatal rats for investigating the protective effect of IP. Methods The cells were randomized into eleven groups: control, ischemia/reperfusion (I/R), IP1 (preconditioned with ischemia/reperfusion for 5 min), IP2 (preconditioned with 2 cycles of ischemia/ reperfusion for 5 min), IP3 (preconditioned with 3 cycles of ischemia/reperfusion for 5 min), IP4 (preconditioned with ischemia/reperfusion for 10 min), IP5 (preconditioned with 2 cycles of ischemia/reperfusion for 10 min), IP6 (preconditioned with 3 cycles of ischemia/reperfusion for 10 min), IP7 (preconditioned with ischemia/reperfusion for 20 min), IP8 (preconditioned with 2 cycles of ischemia/reperfusion for 20 min), and IP9 (preconditioned with 3 cycles of ischemia/reperfusion for 20 min). PI positive staining rate and changes of D 490 after 3 h ischemia/4 h reperfusion were determined by PI staining and MTT chromatometry. Results ① D 490 value in sinoatrial node cells in each experimental group was significantly lower than that in the control group, but that in IP2, IP3, IP4, IP5, and IP7 groups was significantly higher than that in I/R group (P

Objective To study the effects of mimic ischemic preconditioning (IP) on i and I-LCa of sinoatrial node cells and explore the protective effects of IP. Methods Cells were randomized to three groups: control, ischemia/reperfusion (I/R), IP. After labeled with fura4, fluorescence intensity of i was studied with laser confocal microscopy and I-LCa was recorded by whole-cell patch clamp technology. Results IP significantly reduced the fluorescence intensity of i and enhanced the peak of I-LCa as compared with I/R, shifted the I-V curve to more negative value. Conclusion IP can reduce the overload of i caused by I/R and increase I-LCa weakened by I/R.

Objective To compare the effects of stimulated ischemic preconditioning (IP) and ischemia/reperfusion (I/R) on the hyperpolarization-activated current (I_ f ) of sinoatrial node cells and explore the mechanisms of electrophysiological protection of IP. Methods The sinoatrial node cells cultured for 2 d were randomized to three groups: ① Control in which the cells were cultured at 37 ℃ in the mimic reperfusion solution, meanwhile the mixture of 95% O_ 2 and 5% N_ 2 was ventilated; ② I/R in which the cells were cultured in the mimic ischemic solution and simultaneously the mixture of 95% O_ 2 and 5% N_ 2 was ventilated for 3 h, then cultured in the mimic reperfusion solution and simultaneously the mixture of 95% O_ 2 and 5% N_ 2 was ventilated for 4 h; ③ IP in which the cells underwent ischemia for 10 min and reperfusion for 10 min, repeated once. Then the cells were treated as the same as the I/R group. After 4-hour reperfusion, I_ f was recorded by whole-cell patch clamp technology. Results I/R significantly enhanced the current density of I_ f , shifted the current activation curve to more positive value by changing the half-activation voltage from (-98.9?2.4) mV to (-85.2?2.5) mV (P

AIM: To evaluate the effect of hypoxic preconditioning (HP) on the cytoskeleton of sinoatrial node cells primarily cultured from neonatal rat. METHODS: Cells were randomized to three groups of control, hypoxia/reoxygenation ( H/R) and HP. F-actin, vinculin, ?-tubulin and desmin were studied with laser confocal microscopy after labled with different immune fluorescent agents. RESULTS: Compared with control, although both H/R and HP reduced the fluorescence intensity of these four cytoskeletal proteins remarkably (P