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Yong Cao

Publications and source records attributed to Yong Cao.

At least 37 records · Page 2Linked to original sources
PubMed2005

[Photodynamic diagnosis and fluorescence-guided resection of malignant gliomas: a report of 15 cases].

OBJECTIVE: To study the usefulness of the intraoperative photodynamic diagnosis (PDD) and fluorescence-guided resection of malignant gliomas. METHODS: Fifteen consecutive patients with malignant gliomas received doses of hematoporphyrin derivative (HPD, 2 mg/kg body weight) 48 hours before induction of anesthesia. After the tumors recognized by bare eyes they were removed routinely. The fluorescence around 690 nm excited by laser beam (wavelength 632.5 nm) was detected by laser electronic spectrum analyzer and then fluorescing tissue was removed whenever it was considered safel. Tissue samples derived from the walls of tumor cavities after resection and PDD were sent for histological examination. Compared with the result of the histological examination, the sensitivity and specificity of PDD were calculated and recorded. Early postoperative MRI or CT were done to determine the extend of the resection of the tumors. Surgical mortality and morbidity were also recorded. RESULTS: Intraoperatively, in all of 15 cases tumor areas with HPD fluorescence could be recognized by laser electronic spectrum analyzer. On the basis of 106 tissue samples derived from 15 tumors, a sensitivity of 90.6%, a specificity of 96.8% and an accuracy of 94.3% of PDD were achieved. In 2 cases the resection of residual tumor were performed after finding left tumors by PDD. Complete resection of contrast-enhancing tumor was accomplished in 9 patients (60%). Residual intraoperative tissue fluorescence left unresected for safety reasons predicted residual enhancement on MR images in 5 of the 6 remaining patients. No perioperative deaths and one case of morbidity were encountered. CONCLUSIONS: Intraoperative photodynamic diagnosis following resection of malignant gliomas can detect residual tumor tissue with high accuracy. Photodynamic diagnosis and fluorescence-guided resection of malignant gliomas have a positive role in improving the radicality of malignant glioma resection.

Adult↗
PubMed2004

Giant extended pi-conjugated dendrimers containing the 10,15-dihydro-5H-diindeno[1,2-a;1',2'-c]fluorene chromophore: synthesis, NMR behaviors, optical properties, and electroluminescence.

This paper reports the facile synthetic strategy of a series of novel pi-conjugated dendrimers (G0 and G1) based on 10,15-dihydro-5H-diindeno[1,2-a;1',2'-c]fluorene (truxene) in which the benzene cores are generated "in-situ" from acetyl aromatics by the acid-promoted cyclotrimerizations. The unique NMR behaviors, physical properties, and electroluminescence device applications are also presented. Besides the purity, the structure, and the confirmation of the successful formation and isolation of desired compounds by clear assignments of every molecule by (1)H and (13)C and 2D NMR characterizations, several astonishing NMR behaviors have been observed in various solvents. For 1, chemical shift values belonging to H-2' of hexyl substituents move to the most upfield; however, such chemical shift values move from 0.48 to 0.85 ppm when pyridine-d(5) or benzene-d(6) is used as solvent. Our dendrimers as the emissive layers in organic light-emitting diodes gave blue-green light with an external quantum efficiency up to 0.16% both for G0 and for G1 in nitrogen, respectively, which exhibit unique electroluminescence spectra in comparison with their corresponding photoluminescence ones.

Journal Article↗
PubMed2004

High-efficiency, environment-friendly electroluminescent polymers with stable high work function metal as a cathode: green- and yellow-emitting conjugated polyfluorene polyelectrolytes and their neutral precursors.

A series of aminoalkyl-substituted polyfluorene copolymers with benzothiadiazole (BTDZ) of different content were synthesized by Suzuki coupling reaction, and their quaternized ammonium polyelectrolyte derivatives were obtained through a postpolymerization treatment on the terminal amino groups. Copolymers are soluble in environmentally friendlier solvents, such as alcohols. It was found that the efficient energy transfer occurs by exciton trapping on the narrow band gap BTDZ site under UV illumination. Only 1% of BTDZ content is needed to completely quench a fluorene emission for both the neutral and the quaternized copolymers in the neat film. Absolute PL efficiencies of copolymer films were greatly enhanced as a result of the suppression of excimer formation. Light-emitting devices fabricated from these copolymers show high external quantum efficiencies over 3% and 1% for the neutral precursor and the quaternized copolymers, respectively, with high work function metals such as Al as a cathode. To the best of our knowledge, this is the first report on an electroluminescent polymer which bears the high EL efficiency, the electron-injection ability from high work function metals, and the solubility in environment-friendly solvents at the same time. These features make them a promising candidate for the next generation of light-emitting copolymers in PLED flat panel display application.

Journal Article↗
PubMed2004

[Effect of lanthanum chloride on expressions of collagen protein in a wound tissue].

OBJECTIVE: To evaluate the effect of lanthanum chloride on expressions of collagen protein and find a way to prevent and treat scar. METHODS: Four linear incisions were made on the dorsal skin of an adult, female Sprague-Dawley rat as an animal model. One was non-manipulated as a control; the second was injected with distilled water as a sham-control; the third was injected with 50 mmol/L of lanthanum chloride, and the fourth was injected with 50 micrograms neutralizing antibody of TGF-beta 1 as a positive control. All of the wound tissues were harvested and assayed with ABC method in 14 days and 28 days after the surgery. RESULTS: The expressions of type I, III and IV of collagen protein in the third group significantly reduced in 14 and 28 days after the operation, compared with the control or sham-control group. Its values wen as similar as the fourth group. CONCLUSION: Lanthanum chloride could inhibit the expressions of collagen protein, and it may be used to prevent and treat scars.

Animals↗
PubMed2004

[Study on antitumor and synergy effect of "bushen huayu jiedu formula" on mice hepatocarcinoma H22].

OBJECTIVE: To explore antitumor and synergy effect of "Bushen Huayu Jiedu Formula" (BSHYJDF) on hepatocarcinoma H22. METHODS: Transplanted hepatocarcinoma H22 mice were used, the inhibitory rates of H22 were observed respectively to BSHYJDF and BSHYJDF combined with cisplatin (DDP). RESULTS: BSHYJDF could significantly inhibit hepatocarcinoma H22 in transplanted mice (P < 0.05). CONCLUSION: BSHYJDF had inhibitive effect and synergy with chemotherapy to a certain extent in transplanted hepatocarcinoma mice.

Animals↗
PubMed2004

[Development and evaluation of a composite structural filter for removal of arsenic in drinking water].

OBJECTIVE: To develop a composite structural filter and evaluate its performance on-site for removal of high level arsenic in drinking water. METHODS: Composite filters were manufactured using iron loaded carbon powder and superfine PE resin as main components. Test water was prepared by spiking arsenic in raw drinking water. The filter application safety and removal effects on arsenic and other parameters were tested. RESULTS: The composite structural filter made of iron loaded carbon powder and superfine PE resin in equal quantity was safe for drinking water treatment and reached a capacity of 2.56mgAs/g for water with arsenic concentration of 0.4mg/L, and improved water turbidity and chemical oxygen demand apparently. CONCLUSION: The composite filter manufactured using iron loaded carbon powder and superfine PE resin as main components was appropriate for removal of arsenic in rural drinking water with high level of arsenic.

Arsenic↗
PubMed2004

[Effects of meteorological factors and mineral elements on the content of resveratrol in Polygonum cuspidatum rootstalk].

By determining monthly the content of resveratrol and eight mineral elements (Ca, Cu, Fe, K, Mg, Na, Zn, Mn) in the rootstalk of Polygonum cuspidatum, by considering the dynamic meteorological factors and by analyzing the principal components, we are investigating the dynamic relationship laws among mineral elements, meteorological factors and the content of resveratrol in Polygonum cuspidatum rootstalk in varied seasons. The results indicated that the correlation coefficient between Cu and Fe; between Mg and K; between Mg and Zn; between K and Zn; between Ca and average sunlight hours per month are 0.812, 0.871, 0.793, 0.729, 0.602. Their correlation is markedly in the positive 0.01 levels. The correlation coefficient between Cu and average air temperature in a month; between Mn and average air temperature in a month; between Fe and K are -0.738, -0.712, -0.766. Their correlation is markedly in negative 0.01 levels. The correlation between Cu and the content of resveratrol is markedly in negative 0.05 levels. Of the five principal factors affecting the content of resveratrol, two were found to be principal: "mineral element factors of promoting enzyme reacts" and "the meteorological factors of high temperature and strong shines". The percentage results of these two principal are 33.539% and 33.358%, making a total of 68.897%. The two factors above are also the main reasons for the variation of Polygonum cuspidatum resveratrol. A regression equation was set up through correlation and regression analysis between the changing content of resveratrol and the principal component.

Calcium↗
PubMed2004

[Spectral determination of the contents of mineral elements in polygonum cuspidatum].

The present paper reports the determination of mineral elements by FAAS, including K, Ca, Na, Mg, Fe, Zn, Mn and Cu. The best condition for the determination was investigated. The best ionization inhibitor and acidity media were confirmed. The experiment used CsCl to prevent ionization interference, and the concentration of HCl was controlled below 2%. At the same time SrCl prevented interference of P to Ca. So the value of absorbance was stable. The results were obtained by calibration curve method. The analysis method is simple, rapid, accurate and fitting to the determination of mineral elements in plants. The recoveries of the method are 90.5%-108.2%. The relative standard deviations are 0.3%-0.7%. The result show that large amounts of mineral elements are embodied in polygonum cuspidatum. The contents of K and Ca are in conformation with the medical effects of polygonum cuspidatum, and each element is related closely to its growing.

Calcium↗
PubMed2003

Cloning genomic INGAP: a Reg-related family member with distinct transcriptional regulation sites.

The protein product of hamster islet neogenesis-associated protein (INGAP) cDNA induces new pancreatic islet development. Manipulation of this process provides a new therapeutic strategy for the treatment of diabetes. As regulators of INGAP gene expression are unknown over 6 kb of hamster genomic INGAP has been cloned. Sequence analysis has identified a 3 kb 5-prime region with core promoter elements that is rich in transcription factor binding sites and six exons for the coding region. Analysis of promoter activity reveals stimulus-responsive DNA elements which have been identified though deletion analysis. Comparison of transcription factor binding sites in INGAP to the related gene RegIIIdelta exposes potential sites for differential gene regulation.

Animals↗
PubMed2003

[Study on effect of drug concentration of "Bushen huayu jiedu fang" drug serum on drug-resistance lung cancer cells with serum pharmacology].

To explore Rh123 ion concentration effect of "Bushen huayu jiedu fang" (BSHYJD) on drug-resistance lung cancer cells, tumor-bearing animal drug-serum pharmacology and flow cytometry method were utilitied. In contrast with normal animal drug serum, BSHYJD drug-serum of tumor-bearing animal would markedly increase Rh123 concentration in drug-resistance lung cancer cells(P < 0.05), but which hasn't marked discrepancy in contrast with normal animal drug-serum(P > 0.05), that indicated BSHYJD drug-serum has increased drug concentration in drug-resistance lung cancer cells.

Animals↗
PubMed2003

[Effects of lanthanum chloride on the apoptosis of fibroblasts in trauma tissue].

OBJECTIVE: To investigate the effects of lanthanum chloride on the apoptosis of fibroblasts in trauma tissue. METHODS: Fifty adult female SD rats were used and linear incisions were made on the back near the joints of extremities of the rats. One of the cuts receiving no treatment was designated as blank control (C). 0.25 ml of distilled water, lanthanum chloride (50 mmol/L) and the antibody of (TGFbeta(1)) transforming growth factor beta(1) (0.2 mg/ml) were respectively injected into the both sides of the other three wounds subcutaneously and the wounds were divided into simulating control (SC), lanthanum chloride (LC) and antibody (A) groups. The fibroblast apoptosis in the wound tissue samples and the change in intracellular calcium concentration (Ca(2+)) were determined by flow cytometry (FCM) and TUNEL methods on the 14th and 28th day after the injection. RESULTS: Apoptosis of fibroblasts was enhanced significantly after 14 days of injection in LC and A groups compared with that in C and SC groups (P < 0.05 approximately 0.01). Furthermore, intracellular Ca(2+) was increased evidently in LC group (P < 0.01). CONCLUSION: It is indicated that lanthanum chloride might be effective in preventing scar development.

Animals↗
PubMed2002

Monocyte chemoattractant protein-1 mRNA in human intracranial aneurysm walls.

OBJECTIVE: To investigate the pathological course in intracranial aneurysms. METHODS: Normal intracranial artery tissue (cortex fistulization) from 1 case, ruptured aneurysms tissuses from 11 cases, unruptured aneurysm tissues from 2 cases were obtained by neurosurgical excision. Routine HE staining was used to observe histological characteristics. In situ hybridization was used to observe the expression of the monocyte chemoattractant protein-1 (MCP-1) mRNA in the walls of the normal artery and aneurysms. RESULTS: By the HE staining showed that the wall of the ruptured aneurysms (10 cases) and unruptured ones (2 cases) had increased intima and connectivum extima. The fibroblast in the intima was arrayed in the disorder. Monocyte-like cells can be seen in the whole aneurysm wall. In one case aneurysms wall (ruptured) glass-like fiber structure was left over, few cells could be seen. In 9 cases, mural thrombus was found. The thrombus represented with organization. In situ hybridization, MCP-1 mRNA was not detectable in the normal artery. The hybridization signal could be observed in the ruptured aneurysms (10 cases) and unruptured ones (2 cases) often in the intima. MCP-1 mRNA appeared to be expressed by fibroblast cells in its cytoplasm. Monocyte-like cells had little cytoplasm, and the signal was seldom seen. The hybridization signal was discontinuous in the intima, MCP-1 mRNA expressed where fibroblast and monocyte-like cells assembled. One ruptured aneurysm had no signal because there were no cells only glass-like fiber. Mural thrombus showed upregulated hybridization signal in the cytoplasm of fibroblasts, phlogocytes and endotheliocytes of its micrangium. CONCLUSION: The pathological representation of the ruptured and unruptured aneurysms and the upregulated expresion of MCP-1 in the aneurysm wall suggest that the development of aneurysm may be a course of chronic inflammation in which main inflammatory cells are monocyte-like cells.

Aneurysm, Ruptured↗
PubMed2002

[The relationship between arterial blood oxygen pressure and the changes in blood biochemical indices after partial liquid ventilation in canine inhalation injury].

OBJECTIVE: To explore the therapeutic effects of partial liquid ventilation on canine inhalation injury. METHODS: Mongrel dogs were inflicted with steam inhalation injury and were employed as the model. Partial liquid ventilation was accomplished by slow instillation of into the lungs. The changes in blood superoxide dismutase (SOD), malondialdehyde (MDA), nitric oxide (NO) and arterial oxygen pressure (PaO(2)) were determined. RESULTS: The blood levels of MDA and NO at 2 postburn hours (PBHs) increased obviously but those of SOD and PaO(2) decreased significantly when compared with those before injury (P < 0.05). The blood levels of SOD, MDA, NO and PaO(2) recovered to near preinjury levels after partial liquid ventilation. CONCLUSION: Partial liquid ventilation might be helpful in the management of inhalation injury by raising blood oxygen pressure, antagonizing lipid peroxidation and reducing the in vivo NO production.

Animals↗