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Ming Chen

Publications and source records attributed to Ming Chen.

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

[Assessment of acute mesenteric ischemia with multi-slice spiral CT].

OBJECTIVE: To explore the clinical value of multi-slice spiral CT (MSCT) in diagnosis of acute mesenteric ischemia. METHODS: MSCT, including plain scan, the arterial phase scan, and the portal vein phase scan, was performed in 18 patients who were suspected of acute intestinal ischemia. The mesenteric arteries and portal veins were imaged with techniques including volume-rendered technique, multi-planar reconstruction, and maximum intensity projection-thin. All of them were also examined with digital subtractive angiography (DSA). The diagnostic results of MSCT were compared with those of DSA, and the abnormal MSCT findings were analyzed. RESULTS: Bowel wall thickening, mesenteric edema, and ascites were most commonly seen in venous thromboses, while luminal dilatation and air-fluid levels were commonly seen in arterial embolization. Except that pneumatosis was only seen in transmural infarction, all the abnormal CT findings were found in different patterns and different degrees of ischemia. CONCLUSIONS: The integrated MSCT examination is a valuable tool in diagnosis of acute intestinal ischemia. It can accurately diagnose acute intestinal ischemia and is also useful to assess the degrees of ischemia.

Acute Disease↗
PubMed2006

[Adsorption mechanism of chromium cation by floc-type biosorbent ZL 5-2].

Biosorption of Cr(VI) by the novel biosorbent ZL5-2 produced by Agrobacterium sp. was studied and infrared spectra of native, absorbing and desorbing ZL 5-2 were compared. The initial pH was important for biosorption. The optimum effect on Cr(VI) biosorption was acquired within initial pH 0.5 to approximately 1.5, then with the pH increasing, the effect on Cr6+ biosorption was reduced. The biosorption for Cr(VI) was a quick process,only within 10 min 65.4% Cr(VI) is biosorbed, and the biosorption rate was over 90% after 60 min, then all the Cr(VI) was biosorbed after 80 min. The biosorption were fitted with Langmuir and Freundlich isotherm adsorption equations. The absorbed Cr(VI) could be recovered by desorption and the desorption rate reached 13.696% to approximately 67.9%. Progress of biosorption was reversible adsorption and irreversible adsorption simultaneously through infrared spectra analysis, however the reversible adsorption was more important in the biosorption and the adsorption belongs to physics adsorption.

Adsorption↗
PubMed2006

[Dynamic variations of hepatitis B virus polymerase gene in lamivudine-treated hepatitis B patients].

OBJECTIVE: To study variation features of the hepatitis B virus polymerase gene in chronic hepatitis B patients before and after lamivudine treatment. METHODS: From the serum samples of five CHB patients both before and after 12 months' lamivudine treatment, HBV polymerase gene was amplified and positive DNA fragments were cloned into JM105. Twenty positive clones of every sample were checked with mismatched polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and YMDD variants were sequenced. RESULTS: Among five patients after 12 months lamivudine treatment, M552I mutations in two patients with HBV DNA rebounding and D553G mutation in one non-responder were detected except in two patients with negative HBV DNA. CONCLUSIONS: D553G mutation is probably one of the reasons which caused non-responsiveness to the lamivudine treatment. The mutations of YMDD motif that occurred after lamivudine treatment are caused by the induction of the drug.

Amino Acid Sequence↗
PubMed2006

[Role of female partners in the diagnosis and treatment of erectile dysfunction].

The role of female partners in the diagnosis and treatment of erectile dysfunction (ED) is being paid more and more attention now. ED has serious adverse effects on the sexual experience of female partners, while the attitudes of female partners to ED will have a direct effect on seeking and continuing treatment behavior of ED patients. So it's necessary for clinicians to consider female partners in the clinical practice of ED. The evidence from a recently published clinical trial has demonstrated that vardenafil not only improved ED men's erectile function, but also improved the sexual quality of life for female partners, which was the ideal solution of ED couples.

Erectile Dysfunction↗
PubMed2006

[Effect of fluid shear stress time on the morphological change of rat polarized osteoclasts].

OBJECTIVE: To elucidate the morphological change of rat polarized osteoclasts influenced by different fluid shear stress time. METHODS: Special TRAP dyeing and bone resorption of rat polarized osteoclasts were performed. A fluid shear stress device made in the authors' laboratory was used to enforce shear stress at different times on the polarized osteoclasts for observation on their morphological change and analysis on the kind of change by image analytical software. The time points were 0,15,30,45,60,75,90,105,120 min; the shear stress was 0.29 Pa. RESULTS: Morphologically, the polarized osteoclasts were bigger than other monocytes. They were each about 30 microm in diameter, having about 20 round and black nuclei in cytoplasm. There were large numbers of cellular microfilaments. The areas and diameters of these osteoclasts increased with the times. Statistically, one-way ANOVA showed significant differences between the 0 min group and 30 min, 105 min groups respectively. CONCLUSION: In this study, the morphological change of polarized osteoclasts fluctuated with the increase of fluid shear stress time, and their areas and diameters exhibited a tendency to increase.

Animals↗
PubMed2006

[Isolation of bone marrow-derived rat osteoclast-like cells with the digestion of trypsin].

OBJECTIVE: To obtain highly enriched osteoclasts in vitro. METHODS: The bone marrow cells of 1-day, 12-day, 24-day and 36-day old Sprague-Dawley (SD) rats were separately cultured with the presence of 1,25-(OH)2D3 and dexamethasone, and the osteoclast-like cells were identified by Trap staining and scanning electron microscope observation and were purified by trypsin digestion. The count of Trap positive osteoclast-like cells was analyzed statistically. RESULTS: The osteoclast-like cells of each group were Trap positive cells and could form the bone absorption lacunas in vitro. The amounts of osteoclast-like cells were different statistically between the groups (P < 0.05) except between the groups of 1-day old and 12-day old (P > 0.05). Highly enriched osteoclast-like cells were harvested by the digestion of 0.25% trypsin and 0.02% EDTA. CONCLUSION: It's indicated that a large amount of highly enriched osteoclast-like cells could be obtained through the culture of bone marrow cells of 10-day and 12-day old SD rats with 1,25-(OH)2D3 and dexamethasone and the digestion of trypsin/EDTA.

Animals↗
PubMed2006

[Experimental studies of carcino-embryonic antigen immunosensor based on piezoelectric resonate technology of quartz crystal].

In order to construct a new type of piezoelectric quartz immunosensor for the determination of carcino-embryonic antigen (CEA), the sensor detection pools were consisted of plastic loops and crystals that were 10 MHz quartz AT-cut with gold coated electrodes and the immobilization of the monoclonal antibody against CEA onto gold electrode surface of the quartz crystal was accomplished via Thiol method. Then the immunosensors were used in clinical laboratory. The experimental results showed that the piezoelectric immunosensor had good response to CEA, the frequency shifts were linearly dependent on CEA concentration in the range of 1.56 to approximately 50.00 ng/ml, other antigens such as alpha fetoprotein (AFP), prostate specific antigen (PSA), human chorionic gonadotropin (hCG) did not interfere with the sensor's response. The results obtained from this method were in satisfactory accordance with those obtained by radio immunoassay(P>0.05), The correlation coefficient was 0.90. Piezoelectric immunosensor for determination of CEA has the advantage of high sensitivity, high specificity, unnecessary labeling, simple performing, rapid analysis, low cost, real-time detection and repeated use, etc. It can be used for detecting serum CEA in clinical laboratory.

Antibodies, Monoclonal↗
PubMed2006

[Initial outcome of induction chemotherapy with weekly paclitaxel followed by three-dimensional conformal radiotherapy and concurrent weekly paclitaxel for stage III non-small cell lung cancer].

BACKGROUND & OBJECTIVE: The efficacy of radiotherapy alone on locally advanced non-small cell lung cancer (NSCLC) is poor. Although the combined modality of chemoradiotherapy and dose-escalation of radiotherapy have been the main trends, the optimal modality still remains unknown. This study was to evaluate the toxicity and efficacy of induction chemotherapy (ICT) followed by three-dimensional conformal radiotherapy (3D CRT) and concurrent weekly paclitaxel on unresectable NSCLC. METHODS: Stage III NSCLC patients with favorable conditions were treated with 2 to 4 cycles of carboplatin (AUC=5-6, d1) combined with paclitaxel (175 mg/m(2), d1), then followed by weekly paclitaxel (40 mg/m(2)) and concurrent 3D CRT within 3-4 weeks. The prescription dose was given as high as possible under the condition that V20 < or =31% and spinal cord dose < or =50 Gy. RESULTS: Thirty-one patients were enrolled. ICT was well tolerated. During the concurrent chemoradiotherapy, the treatment of 3 patients was ended ahead of the schedule because of severe pulmonary and heart toxicities; the treatment of 2 patients was delayed for 7 and 12 days because of fatigue. Myelosuppression was mild (16/31): all were grade 1-2 except 1 was grade 3. Lymphocytopenia was more obvious (29/31, grade 3 in 21). Three patients developed grade 3 radiation-induced esophagitis, and 2 developed grade 3-4 radiation-induced pneumonitis. Two developed grade 3 esophageal stricture. No grade 3-4 pulmonary fibrosis was observed. The overall response rate was 74.1%. The 1-, 2-, 3-year overall survival rates were 74.2%, 41.9%, and 34.6%, respectively, with the median survival time of 18.5 months. The 1-, 2-, 3-year local progression-freely survival rates were 64.5%, 32.3%, and 20.5%, respectively, with the median local progression-freely survival time of 14.3 months. CONCLUSIONS: The program of ICT followed by weekly paclitaxel and 3D CRT is accomplished in most of the favorable stage III NSCLC patients. The toxicity is tolerable, and the response rate is inspiriting.

Adult↗
PubMed2006

[Autoantibodies against alpha1 adrenergic receptor related with cardiac remodeling in hypertensive patients by clinical observation].

OBJECTIVE: To investigate the effects of autoantibodies against alpha(-) adrenergic receptor on cardiac remodeling in patients with hypertension. METHODS: Five hundred and fifty three patients with hypertension in our hospital were selected. The autoantibodies against alpha(1) adrenergic receptor in sera of donor were detected by ELISA, and the results of echocardiography were recorded. By multiple logistic regressions, the risk factors were analyzed on left ventricular enlargement of hypertension. RESULTS: The percentage of autoantibodies against alpha(1) adrenergic receptor positive was 32.3% (179/553). There were significant difference between the positive group and negative group on the ratio of left atrial enlargement (53.6%, 44.3%, respectively; P < 0.05) and left ventricular enlargement (12.8%, 6.1%, respectively; P < 0.01). The result of regression analysis demonstrated that 4 risk factors were related to left ventricular enlargement, including male, course of disease, heart rate (HR) and autoantibodies against alpha(1) adrenergic receptor in the serum (all P < 0.05). CONCLUSIONS: The autoantibodies against alpha(1) adrenergic receptor have a relationship with left ventricular enlargement of hypertension. Patients with the activity of autoantibodies against alpha(1) adrenergic might contribute to predict cardiac remodeling.

Adult↗
PubMed2005

Carbon monoxide prevents apoptosis induced by uropathogenic Escherichia coli toxins.

Urinary tract infections (UTIs) are often caused by Escherichia coli (E. coli). Previous studies have demonstrated that up-regulation of heme oxygenase-1 (HO-1) may trigger a survival mechanism against renal cell death induced by E. coli toxins. The present study analyses the role of carbon monoxide (CO), an end product of HO-1, in the survival mechanism. Moreover, we identified hemolysin as a putative pro-apoptotic toxin in the E. coli supernatant. Tubular cells were incubated with CO in the presence or absence of E. coli toxins. Uropathogenic or transformants of non-pathogenic strains expressing hemolysin were used. We found that the survival pathway during E. coli infection might be activated by HO-1-derived production of CO. The protection by CO was also associated with up-regulation of p21 protein expression. Furthermore, we found that in children with pyelonephritis, all the E. coli strains expressing hemolysin induced apoptosis. In E. coli strains not expressing hemolysin, only 45% of the strains could induce apoptosis. In conclusion, generation of CO elicited by HO-1 could promote survival signaling in renal cells. Hemolysin is one of the secreted toxins that are involved in inducing apoptosis during UTI.

Animals↗
PubMed2005

Study of inclusion complex of beta-cyclodextrin and nitrobenzene.

beta-cyclodextrin can react with nitrobenzene to form an inclusion complex which is characterized by (1)H NMR and powder X-ray diffractometry. The ratio of beta-CD to NB in inclusion complex is determined as 1:1. At 25 degrees C, the dissociated constant, K(D), of the inclusion complex is measured as 6.5 x 10(-3) M in neutral solution (pH=7.0), but in alkali (pH=13.5), K(D) is 3.2 x 10(-2) M which is much larger than that measured in neutral.

Magnetic Resonance Spectroscopy↗
PubMed2005

Tocopherol-associated protein suppresses prostate cancer cell growth by inhibition of the phosphoinositide 3-kinase pathway.

Epidemiologic studies suggested that vitamin E has a protective effect against prostate cancer. We showed here that tocopherol-associated protein (TAP), a vitamin E-binding protein, promoted vitamin E uptake and facilitated vitamin E antiproliferation effect in prostate cancer cells. Interestingly, without vitamin E treatment, overexpression of TAP in prostate cancer cells significantly suppressed cell growth; knockdown of endogenous TAP by TAP small interfering RNA (siRNA) in nonmalignant prostate HPr-1 cells increased cell growth. Further mechanism dissection studies suggested that the tumor suppressor function of TAP was via down-regulation of phosphoinositide 3-kinase (PI3K)/Akt signaling, but not by modulating cell cycle arrest or androgen receptor signaling. Immunoprecipitation results indicated that TAP inhibited the interaction of PI3K subunits, p110 with p85, and subsequently reduced Akt activity. Constitutively active Akt could negate the TAP-suppressive activity on prostate cancer cell growth. Moreover, stable transfection of TAP in LNCaP cells suppressed LNCaP tumor incidence and growth rate in nude mice. Furthermore, TAP mRNA and protein expression levels were significantly down-regulated in human prostate cancer tissue samples compared with benign prostate tissues as measured by reverse transcription-PCR, in situ hybridization, and immunohistochemistry. Together, our data suggest that TAP not only mediates vitamin E absorption to facilitate vitamin E antiproliferation effect in prostate cancer cells, but also functions like a tumor suppressor gene to control cancer cell viability through a non-vitamin E manner. Therefore, TAP may represent a new prognostic marker for prostate cancer progression.

Animals↗
PubMed2005

High-dose radiation improved local tumor control and overall survival in patients with inoperable/unresectable non-small-cell lung cancer: long-term results of a radiation dose escalation study.

PURPOSE: To determine whether high-dose radiation leads to improved outcomes in patients with non-small-cell lung cancer (NSCLC). METHODS AND MATERIALS: This analysis included 106 patients with newly diagnosed or recurrent Stages I-III NSCLC, treated with 63-103 Gy in 2.1-Gy fractions, using three-dimensional conformal radiation therapy (3D-CRT) per a dose escalation trial. Targets included the primary tumor and any lymph nodes > or =1 cm, without intentionally including negative nodal regions. Nineteen percent of patients (20/106) received neoadjuvant chemotherapy. Patient, tumor, and treatment factors were evaluated for association with outcomes. Estimated median follow-up was 8.5 years. RESULTS: Median survival was 19 months, and 5-year overall survival (OS) was 13%. Multivariate analysis revealed weight loss (p = 0.011) and radiation dose (p = 0.0006) were significant predictors for OS. The 5-year OS was 4%, 22%, and 28% for patients receiving 63-69, 74-84, and 92-103 Gy, respectively. Although presence of nodal disease was negatively associated with locoregional control under univariate analysis, radiation dose was the only significant predictor when multiple variables were included (p = 0.015). The 5-year control rate was 12%, 35%, and 49% for 63-69, 74-84, and 92-103 Gy, respectively. CONCLUSIONS: Higher dose radiation is associated with improved outcomes in patients with NSCLC treated in the range of 63-103 Gy.

Adult↗
PubMed2005

Long-term results of high-dose conformal radiotherapy for patients with medically inoperable T1-3N0 non-small-cell lung cancer: is low incidence of regional failure due to incidental nodal irradiation?

PURPOSE: To report the results of high-dose conformal irradiation and examine incidental nodal irradiation and nodal failure in patients with inoperable early-stage non-small-cell lung cancer (NSCLC). METHODS AND MATERIALS: This analysis included patients with inoperable CT-staged T1-3N0M0 NSCLC treated on our prospective dose-escalation trial. Patients were treated with radiation alone (total dose, 63-102.9 Gy in 2.1-Gy daily fractions) with a three-dimensional conformal technique without intentional nodal irradiation. Bilateral highest mediastinal and upper/lower paratracheal, prevascular and retrotracheal, sub- and para-aortic, subcarinal, paraesophageal, and ipsilateral hilar regions were delineated individually. Nodal failure and doses of incidental irradiation were studied. RESULTS: The potential median follow-up was 104 months. For patients who completed protocol treatment, median survival was 31 months. The actuarial overall survival rate was 86%, 61%, 43%, and 21% and the cause-specific survival rate was 89%, 70%, 53%, and 35% at 1, 2, 3, and 5 years, respectively. Weight loss (p = 0.008) and radiation dose in Gy (p = 0.013) were significantly associated with overall survival. In only 22% and 13% of patients examined did ipsilateral hilar and paratracheal (and subaortic for left-sided tumor) nodal regions receive a dose of > or = 40 Gy, respectively. Less than 10% of all other nodal regions received a dose of > or = 40 Gy. No patients failed initially at nodal sites. CONCLUSIONS: Radiation dose is positively associated with overall survival in patients with medically inoperable T1-3N0 NSCLC, though long-term results remain poor. The nodal failure rate is low and does not seem to be due to high-dose incidental irradiation.

Aged↗
PubMed2005

Relationships among stop codon usage bias, its context, isochores, and gene expression level in various eukaryotes.

It is well known that stop codons play a critical role in the process of protein synthesis. However, little effort has been made to investigate whether stop codon usage exhibits biases, such as widely seen for synonymous codon usage. Here we systematically investigate stop codon usage bias in various eukaryotes as well as its relationships with its context, GC3 content, gene expression level, and secondary structure. The results show that there is a strong bias for stop codon usage in different eukaryotes, i.e., UAA is overrepresented in the lower eukaryotes, UGA is overrepresented in the higher eukaryotes, and UAG is least used in all eukaryotes. Different conserved patterns for each stop codon in different eukaryotic classes are found based on information content and logo analysis. GC3 contents increase with increasing complexity of organisms. Secondary structure prediction revealed that UAA is generally associated with loop structures, whereas UGA is more uniformly present in loop and stem structures, i.e., UGA is less biased toward having a particular structure. The stop codon usage bias, however, shows no significant relationship with GC3 content and gene expression level in individual eukaryotes. The results indicate that genomic complexity and GC3 content might contribute to stop codon usage bias in different eukaryotes. Our results indicate that stop codons, like synonymous codons, exhibit biases in usage. Additional work will be needed to understand the causes of these biases and their relationship to the mechanism of protein termination.

Base Sequence↗
PubMed2005

Optical limiter with an organic solution sandwiched between a polymer slab and a polymer grating.

An optical limiter was designed and fabricated. The device consists of an organic solution sandwiched between a polymer slab and a transparent relief polymer grating with a triangular groove. At low power the device has a high transmittance because the refractive index of the solution is matched with those of the slab and the grating materials and because the grating does not diffract. However, high power makes the organic solution thermally vaporize and makes the indices of the solution, slab, and grating materials become mismatched, which causes the grating to appear. The incident light is strongly absorbed, scattered, and self-defocused by the organic solution, and the grating suppresses the zero-order diffraction. Thus the transmitted light energy becomes lower than the damage threshold of human eyes or optical sensors. The device is an effective protection for human eyes or optical sensors against broadband pulsed-laser damage.

Journal Article↗
PubMed2005

Involvement of midgastric transverse band in gastric emptying delay of functional dyspepsia.

BACKGROUND: Midgastric transverse band (MTB) was first observed over 100 years ago, after that many researchers worked on the subject postulated its physiologic role and the role in gastrointestinal diseases, but its function remains unclear. With progress of imaging methods, the nature of MTB is unveiling. In this study we investigated the effect of MTB on the gastric emptying delay in functional dyspepsia (FD) and explored the mechanism. METHODS: A total of 60 patients with FD and 65 age- and sex-matched healthy people who served as controls were studied. With (99m)Tc-DTPA labeled semi-solid fat-parched flour served as test meal, gastric emptying was examined in all subjects by using single photon emission computed tomography. Test meal was designated as general (60 g fat-parched flour) or large (80 g fat-parched flour) meal. Stomach was divided into proximal and distal parts by MTB. Half gastric emptying time, areas of different gastric parts, intragastric food distribution and MTB width were tested with in given times. RESULTS: Patients with FD showed a delayed gastric emptying and increased intragastric residue. Global and regional gastric emptying velocity was decreased. The areas of distal stomach and MTB were significantly greater in the FD patients than in the controls. Throughout the whole test period a distal stomach-dominated food distribution was shown. Those who took a large meal had longer half gastric emptying time and greater MTB area than those who took a general meal. CONCLUSIONS: Gastric emptying delay is related to enlarged MTB area. Some dyspeptic symptoms may be induced by abnormal distribution and increased retention of food in distal stomach. MTB, being like atria-ventricular valve that controls blood flow in heart, regulates transport, distribution, and emptying of food in the stomach.

Adult↗