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Ping Chen

Publications and source records attributed to Ping Chen.

At least 55 records · Page 3Linked to original sources
PubMed2006

Prenatal development of intrafetal and maternal-fetal synchrony.

Fetal and maternal data were monitored serially at 6 gestational ages from 20 to 38 weeks in 195 Peruvian fetuses. Digitized data included fetal heart rate and motor activity, as well as maternal heart rate and electrodermal conductance. Time series analysis evaluated the development of synchrony in 2 streams of fetal functioning and between mothers and fetuses. Intrafetal synchrony between heart rate and motor activity developed in an orderly fashion, with peak cross-correlation approaching an asymptote at 5 s at 28 weeks. Synchrony was not observed between fetal heart rate and maternal measures. Fetal motor activity exhibited synchrony with both maternal electrodermal and heart rate activity. Implications for revealing fundamental properties of neural development prior to birth are discussed.

Cardiotocography↗
PubMed2006

Adverse effects of gabapentin and lack of anti-allodynic efficacy of amitriptyline in the streptozotocin model of painful diabetic neuropathy.

Amitriptyline and gabapentin are the primary treatments for painful diabetic neuropathy (PDN), and it is clear that they produce beneficial effects, but there are questions about these treatments that have not been adequately addressed. For example, although there is a growing consensus that the therapeutic effects of amitriptyline in pain patients are independent of its effects on mood, it is not clear that amitriptyline has specific and direct effects on pain. There is also a fairly broad consensus that gabapentin is safe and well tolerated, but the side-effect profile of gabapentin has not been adequately assessed in pain populations. The rat streptozotocin (STZ) model of PDN was used (a) to assess the effects of amitriptyline on objective, quantitative measures of tactile allodynia, a common type of pain in PDN patients, and (b) to assess the side effects of gabapentin using measures of motor/ambulatory and cognitive function. Amitriptyline did not attenuate STZ-induced mechanical allodynia, even after chronic administration of high doses. Gabapentin produced robust anti-allodynic effects but also produced deficits in tests of motor/ambulatory and cognitive functions. The present experiments suggest that the beneficial effects of amitriptyline in PDN may not be a result of anti-allodynic efficacy and that gabapentin produces robust anti-allodynic effects but may also produce significant motor and cognitive deficits even at or near the lowest effective doses. These findings challenge the consensus opinions about these primary treatments for PDN and suggest that their therapeutic and adverse effects should be explored further in pain patients.

Amines↗
PubMed2006

Involvement of PKC, p38 MAPK and AP-2 in IL-1beta-induced expression of cyclooxygenase-2 in human pulmonary epithelial cells.

OBJECTIVE: The aim of this study was to identify the signal molecules involved in IL-1beta-induced expression of cyclooxygenase (COX)-2 in human pulmonary epithelial (A549) cells. METHODS: A549 cells were stimulated with IL-1beta in the presence or absence of H-7 (a protein kinase C inhibitor), SB203580 (a p38 mitogen-activated protein kinase inhibitor) and PD098059 (a mitogen-activated and extracellular regulated kinase kinase (MEK1) inhibitor). The A549 cells were also transfected with adenovirus vector encoding activator protein (AP)-2alpha, or a plasmid containing a dominant-negative gene (AP-2Delta), in the presence or absence of IL-1beta. RESULTS: IL-1beta induced expression of the COX-2 mRNA and protein in A549 cells in a time- and dose-dependent manner. SB203580 and H-7, but not PD098059, inhibited IL-1beta-induced expression of COX-2 protein. Overexpression of AP-2alpha increased expression of the COX-2 protein, whereas AP-2Delta decreased IL-1beta-induced COX-2 expression. CONCLUSION: Protein kinase C, p38 mitogen-activated protein kinase and transcriptional factor AP-2alpha may play important roles in regulating IL-1beta-induced COX-2 expression in human pulmonary epithelial cells.

Cell Line, Tumor↗
PubMed2006

Proteomic analysis of rat hippocampal plasma membrane: characterization of potential neuronal-specific plasma membrane proteins.

The hippocampus is a distinct brain structure that is crucial in memory storage and retrieval. To identify comprehensively proteins of hippocampal plasma membrane (PM) and detect the neuronal-specific PM proteins, we performed a proteomic analysis of rat hippocampus PM using the following three technical strategies. First, proteins of the PM were purified by differential and density-gradient centrifugation from hippocampal tissue and separated by one-dimensional electophoresis, digested with trypsin and analyzed by electrospray ionization (ESI) quadrupole time-of-flight (Q-TOF) tandem mass spectrometry (MS/MS). Second, the tryptic peptide mixture from PMs purified from hippocampal tissue using the centrifugation method was analyzed by liquid chromatography ion-trap ESI-MS/MS. Finally, the PM proteins from primary hippocampal neurons purified by a biotin-directed affinity technique were separated by one-dimensional electrophoresis, digested with trypsin and analyzed by ESI-Q-TOF-MS/MS. A total of 345, 452 and 336 non-redundant proteins were identified by each technical procedure respectively. There was a total of 867 non-redundant protein entries, of which 64.9% are integral membrane or membrane-associated proteins. One hundred and eighty-one proteins were detected only in the primary neurons and could be regarded as neuronal PM marker candidates. We also found some hypothetical proteins with no functional annotations that were first found in the hippocampal PM. This work will pave the way for further elucidation of the mechanisms of hippocampal function.

Animals↗
PubMed2006

Rho-kinase as a potential therapeutic target for the treatment of pulmonary hypertension.

Pulmonary hypertension (PH) is a cardiovascular disorder characterized by vasoconstriction and vascular remodeling. Recently, rapidly increasing evidence from various rat models of PH and patients with PH suggest that small GTPase Rho and its downstream effector, Rho-kinase, play a key role in the pathogenesis of PH. Activation of the Rho/Rho-kinase pathway is important for pulmonary endothelial dysfunction, pulmonary vascular smooth muscle cell contractility, proliferation and apoptosis in PH. A greater Rho-kinase expression and an enhanced Rho-kinase activity have been observed in pulmonary arteries of PH rats, such as hypoxia-induced, monocrotaline-induced and genetic spontaneous PH rats. Moreover, Y-27632 or fasudil, the selective Rho-kinase inhibitors, significantly attenuated PH in various pulmonary hypertensive model rats and patients with PH, but did not reduce systemic blood pressure. Therefore, Rho-kinase inhibitors may have therapeutic potential for the treatment of PH.

Animals↗
PubMed2006

Serum matrix metalloproteinase 9 as a marker for the assessment of severe acute pancreatitis.

Previous studies have shown that matrix metalloproteinase 9 (MMP-9) degrades basement membrane components in inflammation, but the change of serum MMP-9 level in the progression of acute pancreatitis remains unclear. The aim of our study was to assess the value of MMP-9 as a prognostic marker in acute pancreatitis. The prospective study included 10 patients with severe acute pancreatitis (SAP) and 10 patients with mild acute pancreatitis. The study also enrolled 10 healthy individuals as control. The serum MMP-9 level, serum C-reactive protein (CRP) level, serum tumor necrosis factor alpha (TNF-alpha) level and acute physiology and chronic health evaluation (APACHE) II score were measured at 1 hr and 48 hrs after admission. APACHEII scores and serum MMP-9, TNF-alpha and CRP levels were significantly increased in patients with SAP compared to those with mild acute pancreatitis and control subjects at 1 hr after admission (p < 0.01). When the states of illness were improved, the levels of the above-mentioned markers were decreased in patients with SAP at 48 hrs after admission (1 hr vs 48 hrs, p < 0.01 or p < 0.05). Furthermore, significant positive correlation was found between serum MMP-9 level and serum TNF-alpha level, serum CRP level or APACHEII score in patients at 1 hr after admission (MMP-9/TNF-alpha, r = 0.956; MMP-9/CRP, r = 0.935; MMP-9/APACHE II score, r = 0.957; p < 0.01). These results suggest that MMP-9 is involved in the deterioration of SAP and serum MMP-9 level is a valuable assessment marker for the severity of SAP.

APACHE↗
PubMed2006

Captopril, an Angiotensin-converting enzyme inhibitor, attenuates the severity of acute pancreatitis in rats by reducing expression of matrix metalloproteinase 9.

It has been reported that matrix metalloproteinase 9 (MMP-9) disrupts basement membrane and increases vascular permeability. MMP-9 therefore might participate in the pathogenesis of severe acute pancreatitis (SAP). Captopril, an angiotensin-converting enzyme inhibitor, could reduce MMP-9 expression. However, the effect of captopril on the outcome of SAP is not ascertained. The aim of this study was to determine whether captopril attenuates the severity of SAP by reducing MMP-9 expression. Thirty Sprague-Dawley rats were randomly divided into 3 groups (n = 10 for each). Rats were given intraperitoneal injection of saline (SAP group) or captopril (4 mg/kg) (treated group), and then given retrograde infusion of 5% sodium taurocholate (1.5 ml/kg) into the pancreatic duct under laparotomy to induce SAP. One group of rats, injected with saline, underwent only sham operation (Control). Experimental samples were collected at 24 hrs after the induction of SAP or sham operation. Various markers of severity of SAP, such as serum levels of amylase and trypsinogen activation peptide and the vascular permeability, were increased in rats with SAP, but were significantly decreased in captopril-treated rats (p < 0.01). Likewise, the serum MMP-9 levels and expression levels of pancreatic tissue MMP-9 were significantly higher in rats with SAP than those in captopril-treated rats and control rats (p < 0.01 for both parameters), but showed no difference between captopril-treated and control rats. These results suggest that captopril may attenuate vascular permeability by reducing MMP-9 expression in SAP, thereby ameliorating severity of the disease. The use of captopril might become a new therapeutic agent for SAP.

Amylases↗
PubMed2006

[Relationship between sinusoidal endothelial cell apoptosis and hepatocyte injury after their transplantation into rats].

OBJECTIVES: To investigate the relationship between the apoptosis of sinusoidal endothelial cells (SEC) and the hepatocyte injury of the livers after their transplantation into rats. METHODS: Male SD rats were divided into three groups randomly: sham group, UW1h group and UW12 h group. Orthotopic liver transplantations were performed using the technique described by Kamada with a modification. A survival rate curve was made using the Kaplan-Meier method. Liver tissue specimens and blood samples were collected at different time points after the surgeries. Six animals were sacrificed at each time-point. The liver injury was evaluated by serum ALT and HA levels. The incidence of apoptosis in SECs was measured using the Tunel method. Additionally, the typical morphology indication of apoptosis was observed by transmission electron microscopy. RESULTS: The survival rate at 168 h in the UW12 h group was significantly lower than that in the UW1h group (F = 6.39, P<0.05). The levels of serum ALT and HA were significantly higher in UW12 h group than those in UW1h group (F = 3.99, P<0.05; F = 12.43, P<0.05). The serum ALT level reached its peak at 6 h after transplantation in both groups. The AI of SEC was significantly higher in the UW12 h group than those in the UW1h group and sham group (F = 63.58, P<0.01; F = 86.58, P<0.01). The apoptosis index (AI) in the UW1h group and in the UW12 h group both reached their peak at 6 h postoperatively and the AI of SEC of each group was positively correlated with their serum ALT levels significantly (r = 1.0, P,0.01; r = 0.962, P<0.05). CONCLUSION: The increase of apoptosis of SEC is significantly correlated with the dysfunction of the livers after transplantation in rats, and the dysfunction was mainly caused by the process of cold preservation/reperfusion injury.

Animals↗
PubMed2006

[Effects of electromagnetic fields of different frequencies on proliferation and DNA damage of gallbladder cancer cells].

OBJECTIVE: To study the effects of low-power electromagnetic fields of different frequencies on proliferation and DNA damage of gallbladder cancer cells. METHODS: The cell growth curve was drawn and single cell gel electrophoresis performed to evaluate the proliferation and DNA damage of gallbladder cancer cells respectively after the cells were exposed to electromagnetic fields of different frequencies. RESULTS: After exposure to low-power electromagnetic fields of different frequencies (0.1-40 MHz), the cells displayed significant changes with obvious cell proliferation inhibition and DNA strand breakage. CONCLUSION: Low-power electromagnetic fields within the range of 0.1-40 MHz may impair the DNA strand and cause inhibition of proliferation of the gallbladder cancer cells, and these effects are related to the frequency of the electromagnetic fields but not in a linear fashion.

Cell Line, Tumor↗
PubMed2006

[Application of sequential noninvasive following invasive mechanical ventilation in COPD patients with severe respiratory failure by investigating the appearance of pulmonary-infection-control-window].

OBJECTIVE: To evaluate the application of sequential noninvasive following invasive mechanical ventilation in chronic obstructive pulmonary disease (COPD) patients with severe respiratory failure by investigating the appearance of pulmonary-infection-control-window. METHODS: From November 2001 to October 2004, 76 case of COPD patients with severe respiratory failure due to pulmonary infection were intubated and recruited in the study. When the pulmonary infection was significantly controlled (the time of pulmonary infection control was called PIC window) by the antibiotic and comprehensive therapy, all cases were randomized into noninvasive veatiation group (NIV) and control group. The early extubation was conducted and followed by noninvasive mechanical ventilation via facial mask with bilevel positive airway pressure mode immediately in the NIV group. Conventional invasive synchronized intermittent mandatory ventilation (SIMV) plus pressure support ventilation (PSV) was used as the weaning technique in the control group. RESULTS: Thirty eight cases among 76 patients were in the NIV group, and the rest in the control group. The NIV group and the control group had similar age, sex, APACHE scores, RR, HR, MAP, PaO2 and PaCO2 at the time of commencement and PIC window (P > 0.05). The time of PIC window was (7.5 +/- 1.9) d in the NIV group, and (8.0 +/- 2.5) d in the control group (P > 0.05). In the NIV group, the durations of invasive mechanical ventilation (MV) and total MV were (7.5 +/- 1.9) d and (12.5 +/- 4.0) d respectively, while the durations were (23.5 +/- 9.5) d in the control group (P < 0.05). The durations of RICU stay and hospital stay were shorter than that in the control group. The incidence of ventilation associated pneumonia (VAP) was 18.4% (7/38) in the NIV group, 39.5% (15/38) in the control group respectively (P < 0.05). The incidence of reintubation was 13.2% (5/38) in the NIV group, 34.2% (13/38) in the control group respectively (P < 0.05). Hospital mortality was 7.9% (3/38) in the NIV group, and 28.9% (11/38) in the control group (P < 0.05). CONCLUSION: In those COPD patients requiring intubation and mechanical ventilantion who have severe respiratory failure due to pulmonary infection, sequential noninvasive following invasive mechanical ventilation at the appearance of PIC window can significantly reduce the MV duration, the length of RICU stay and hospital stay, and decrease the occurrence of VAP, reintubation and hospital mortality as well. So it is an efficient strategy to be generalized.

Aged↗
PubMed2006

[Identification of the isoform in type II receptor of transforming growth factor-beta in patients with acute leukemia and its clinical significance].

Recent research indicates that TGF-beta and type II receptor (TbetaR-II) play an important role in the pathogenesis of tumor. A high frequency of abnormalities in TbetaR-II has been demonstrated in various cancers. To identify the mutation of TbetaR-II in patients with acute leukemia, the bone marrow samples from 6 patients with acute leukemia and 11 normal individuals as control were detected by long-range RT-PCR. To detect a deletion in sequence of the TbetaR-IIgene, the PCR products were cloned to T vector and then sequenced. The results showed that there was existance of the isoform of TbetaR-II in 2 cases out of 6 patients with acute leukemia. These two patients had more poor prognosis than others. In conclusion, there was the isoform of TbetaR-II in partial patients with acute leukemia, and the isoform may be related with prognosis.

Adult↗
PubMed2006

[A multicentre study on the pathogenic agents in 665 adult patients with community-acquired pneumonia in cities of China].

OBJECTIVE: To investigate the pathogenic causes of community-acquired pneumonia (CAP) in adult patients in China, the relation of previous antibiotic use and the Pneumonia Patient Outcome Research Team (PORT) classification to microbial etiology, and the prevalence of drug resistance of common CAP bacteria. METHODS: A prospective study was performed on 665 consecutive adult patients with CAP at 12 centers in 7 Chinese cities during one year. The etiology of pneumonia was considered if one of the following criteria was met: (1) valid sputum sample yielding one or more predominant strains; (2) blood cultures yielding a bacterial pathogen; (3) seroconversion, a > or = 4-fold increase or decrease titers of antibodies to Mycoplasma pneumoniae, Chlamydia pneumoniae and Legionella pneumophila. Minimum inhibitory concentration (MIC) of respiratory tract isolates was determined using the agar dilution method. RESULTS: Pathogens were identified in 324/610 patients (53.1%) with valid serum samples and sputum cultures as follows: Mycoplasma pneumoniae (126, 20.7%), Streptococcus pneumoniae (63, 10.3%), Haemophilus influenzae (56, 9.2%), Chlamydia pneumoniae (40, 6.6%), Klebsiella pneumoniae (37, 6.1%), Legionella pneumophila (31, 5.1%), Staphylococcus aureus (23, 3.8%), Escherichia coli (10, 1.6%), Moraxella catarrhalis (8, 1.3%), Pseudomonas aeruginosa (6, 1.0%). Of 195 patients with a bacterial pathogen, an atypical pathogen was identified in 62 (10.2%) cases. The non-susceptibility rate of Streptococcus pneumoniae to penicillin, azithromycin, and moxifloxacin was 20.3%, 75.4% and 4.3% respectively. CONCLUSIONS: Atypical pathogens have important role in CAP, with Mycoplasma pneumoniae being the most common pathogen, and mixed infection of atypical pathogens with bacteria was found in 10.2% of the cases. Streptococcus pneumoniae and Haemophilus influenzae remain the most important bacteria for CAP. More than 75.0% of Streptococcus pneumoniae was resistant to macrolides and 20.3% was resistant to penicillin.

Adult↗
PubMed2006

[Children's bronchoscopy and bronchoalveolar lavage on endogenic foreign body in bronchus].

OBJECTIVE: To investigate the clinical effect of Children's bronchoscopy and bronchoalveolar lavage on endogenic foreign body in bronchus. METHOD: (1) Three hundred and thirty-seven cases had bronchoscopy and bronchoalveolar lavage whose chest X-ray diagnoses were bronchopneumonia with one or two lobe emphysema and/or pulmonary atelectasis, in which 22 cases had severe pneumonia with heart failure and respiratory failure. All cases had no history of foreign bodies' inhalation and become more dyspnea after a three-day treatment of antibiotics. Three hundreds and thirty one cases of bronchoalveolar lavages were divided into two groups randomly using saline or azythromycin, saline group had 126 cases (aged 0 approximately 10 years, mean age, 3 years ); azithromycin group had 211 cases(aged 0 approximately 8 years, mean age, 3.1 years). RESULT: There were 331 cases of endotracheal endogenous purulent emboli, 126 cases in left lung, 178 in right, and 27 cases in both sides. Judging from nature of emboli, 305 cases were mucus, 4 cases were milk valve, 22 cases were white membrane of plastic bronchitis. In azithromycin group, 172 cases (81.2%) were cured, 39 cases (18. 8%) showed effective, the total effective rate was 100 percent. In saline group, 96 cases were cured, 24 cases showed effective, the total effective rate was 100 percent. There wasn't statistically significant between two groups in total effective rate. The average hospitalization time had a statistical significance between saline group (11 days) and azithromycin group (6 days). Two cases of complication of pneumothorax happened in operation. They recovered through closed drainage of thoracic cavity and 3 cases dead. CONCLUSION: Bronchoscopy and bronchoalveolar lavage could shorten the course of endogenic foreign body in bronchus; especially it has significance to those cases of respiratory path obstruction with heart and respiratory failure. Plastic bronchitis could be determined by bronchoscopy and a pathologic histologic examination thereafter.

Bronchi↗
PubMed2006

[Effect of health education on the lung function and life quality in patients with stable chronic obstructive pulmonary diseases].

OBJECTIVE: To evaluate the effect of health education on the symptoms, lung function and life quality in patients with stable chronic obstructive pulmonary diseases (COPD). METHODS: Eighty-two patients were assigned into 2 groups randomly: The treatment group (n = 43) accepted health education for 6 months and the control group (n = 39) did not. Before and after the 6 months, we observed the number of smokers, Borg score, inhale treatment, times of acute episode, SGRQ score, lung function, and the therapeutic effect in the two groups. RESULTS: Six months later, the ratio of smokers in the treatment group was 13.95%, much lower than that in the control group (35.90%, P = 0.021); the Borg score of the treatment group decreased from 4.86 +/- 1.21 to 3.38 +/- 0.94 (P =0.000), but there was no difference in the control group; the ratios of accepted inhale treatment in the treatment group and the control group were 100% (43/43) and 20.51 % (8/39) respectively (P = 0.000), and the accuracy rates were 100% (43/43 ) in the treatment group and 12. 82% (5/39) in the control group (P =0. 000); the times of acute episode in the treatment group was 1.51 +/- 1.53, much lower than that in the control group (4.46 +/- 5.17, P = 0. 000); the indexes of lung function before and after the 6 months between the two groups had no significant difference. The total score, the symptom section score, the activity section score, and the impact section score of SGRQ after the 6 months of health education were much lower than those of 6 months before, and those in the control group had no significant difference. CONCLUSION: Six months of the health education can decrease the ratio of smokers and the times of acute episode, and to improve the life quality of patients with stable COPD.

Adult↗
PubMed2006

[Correlation between pressure-derived coronary collateral flow and Rentrop grade after primary percutaneous intervention of acute myocardial infarction].

OBJECTIVE: To analyze the correlation between pressure-derived collateral coronary flow (PDCF) and Rentrop grade of patients with acute myocardial infarction (AMI). METHODS: PDCF, determined by the ratio of P(w)/P(a), was measured in 29 patients with AMI of the first onset who received primary percutaneous coronary intervention (PCI) within 12 h after the onset. Sufficient collateral flow (group A, n=19) was defined as PDCF>0.24 and insufficient collateral flow (group B, n=10) as PDCF< or =0.24. Rentrop grade of the collateral flow was evaluated by coronary angiography. Echocardiography was performed on the 3rd and 30th day after PCI. The left ventricular ejection fraction, end-systolic and end-diastolic volumes, and the related indexes were obtained. RESULT: Rentrop grade was significantly related to PDCF (r=0.75, P<0.01), but a wide range of PDCF was observed in patients with Rentrop grade< or =1. CONCLUSION: PDCF measurement allows quantitative evaluation of the collateral flow in patients with AMI.

Adult↗
PubMed2006

[A study of the influences of blood sugar levels on the prognosis of fulminating hepatitis patients].

OBJECTIVE: To explore the possible relationship between hypoglycemia and the prognosis of fulminating hepatitis patients. METHODS: Fasting blood sugar levels of 322 fulminating hepatitis patients were retrospectively analyzed. The blood sugar levels and their clinical significance were appraised together. RESULTS: In all the samples, 173 were hypoglycemic (53.73%). The mortality rate of the hypoglycemia group was 48.55% (84/173), therefore the blood sugar level was lower and the mortality rate was higher. CONCLUSION: A higher proportion of fulminating hepatitis patients have hypoglycemia. There is a close relationship between hypoglycemia and the prognosis of the fulminating hepatitis patients. Blood sugar level has an important clinical value in reflecting the degree of liver failure in early fulminating hepatitis patients.

Adult↗