Biomedical subjects

Quan Liao

Publications and source records attributed to Quan Liao.

25 records · Page 2Linked to original sources

PubMed2004

[Non cholangio-contrast cholangiopancreatography using multi-slice spiral CT].

OBJECTIVE: To investigate the feasibility of multi-slice spiral CT (MSCT) for cholangiopancreatography without cholangio-contrast. METHODS: Ten patients without any digestion system diseases and 24 patients with suspected pancreatic malignancy received the 16-slice spiral CT multi-phased contrast-enhanced scanning. The images of patients without any digestion system diseases and cancer-suffered patients were curved reformatted (CR) technique to perform the structure of pancreatic duct, common bile duct, and ampulla. The cholangiopancreatical systems of the cancer suffered patient were reconstructed through volume rendering technique (VRT), minimum intensity projection (MinIP), and indirect minimum intensity projection (IMinIP). The results of patients without any digestion system diseases in curved multiplanar reconstruction were analyzed; meanwhile display rates of the pancreatic duct, common bile duct, and ampulla were evaluated. RESULTS: of the four different cholangiopancreatographies were compared. RESULTS: The display rate of pancreatic duct in the CR images was 90.0 (9/10) with an average diameter of (2.63 +/- 0.51) mm. Sub-pancreatic duct could be seen in 88.9% (8/9) of them. The display rate of common bile duct in the CR images was 100% (10/10) with an average diameter of (7.45 +/- 1.12) mm. The display rate of ampulla was 60.0 (6/10), which was affected by the filling status of duodenum. The cholangiopancreatography using CR, VRT, MinIP, and IMinIP for patients with pancreatic cancer reveal the whole pancreatic and common bile duct, and the modality of distal obstructed bile duct. The result showed that IminIP got the best outcome (98.6%), while VRT got the worst (68.1%). CONCLUSION: The negative CT cholangiopancreatography is a simple and non-invasive examination. It reflects both the 3-dimensional cholangio-pancreatic anatomical structure and its adjacent condition. It has curtain clinical application values, especially for patients with obstructed duct system.

Adult↗

PubMed2004

[Diagnosis and surgical treatment of solid-pseudopapillary tumor of the pancreas].

OBJECTIVE: To study the diagnosis and treatment of solid-pseudopapillary tumor of the pancreas (SPTP). METHODS: The clinical course, surgical treatment, and pathological findings of 13 patients with SPTP were analyzed. RESULTS: SPTP has no specific clinical symptoms. The patients mostly have abdominal pain and space occupying symptoms. Laboratory investigations of some patients showed decreased pancreatic exocrine function and elevated CA242 of tumor markers. Ultrasonography and CT revealed large solid cystic tumor of pancreas. Digital subtraction angiography (DSA) showed lacked-blood-supply space occupying lesion. All tumors were resected successfully. The histological findings showed a large encapsulated tumor and the section of tumor surrounded by hemorrhagic and necrotic areas. The solid areas are composed of small and medium size tumor cells, which had no obvious atypia. Psudopapillary structures were found in the cystic degeneration areas. Immunohistochemically, most of the tumors were positive for alpha-antitrypsin (alpha-AT) and vimentin and negative for chromogrannin. No patients recurrence during the follow-up. CONCLUSIONS: Most of SPTP can be removed successfully after diagnosis. The tumor and local infiltration tissue should be removed completely, and the long-term prognosis of SPTP is good.

Adolescent↗

PubMed2003

Down-regulation of the dual-specificity phosphatase MKP-1 suppresses tumorigenicity of pancreatic cancer cells.

BACKGROUND & AIMS: In both pancreatic cancer and chronic pancreatitis, there is enhanced expression of mitogenic growth factors and their tyrosine kinase receptors, which have the capacity to activate mitogen-activated protein kinase (MAPK). In view of the important role of MAPK kinase phosphatase (MKP)-1 in the regulation of MAPK activation, the expression and functional role of MKP-1 was analyzed. METHODS: Pancreatic tissues were analyzed by Northern blotting, Western blotting, and immunohistochemistry. Pancreatic cancer cells were transfected with a full-length MKP-1 antisense construct. Growth characteristics and tumorigenicity in vivo and the effects of mitogenic growth factors on cell growth and MAPK activation were determined in transfected and control cells. RESULTS: MKP-1 messenger RNA (mRNA) levels were increased in pancreatic cancer and chronic pancreatitis (CP) tissues. Moderate to strong MKP-1 immunoreactivity was present in the cancer cells, ductal cells of pancreatic intraepithelial neoplasia, and in tubular complexes in CP. Down-regulation of MKP-1 resulted in decreased anchorage-dependent and -independent growth of pancreatic cancer cells, and decreased tumorigenicity in a nude mouse tumor model. MKP-1 down-regulation led to decreased proliferation and sustained MAPK activation in response to mitogens. CONCLUSIONS: Suppression of MKP-1 expression reduces the tumorigenicity of pancreatic cancer cells in vivo, suggesting that MKP-1 contributes to enhanced mitogenic signaling in pancreatic cancer cells.

Adolescent↗

PubMed2003

[Preferential expression of cartilage oligomeric matrix protein in degenerating acinar cells in chronic pancreatitis and in chronic pancreatitis-like lesions].

OBJECTIVES: To study cartilage oligomeric matrix protein (COMP) mRNA and protein expression in normal pancreas, chronic pancreatitis (CP), and pancreatic cancer tissues. METHODS: Tissues from 15 cases of normal pancreas, 14 cases of chronic pancreatitis and 14 cases of pancreatic cancer were analyzed by Northern blot, Western blot, in situ hybridization and immunohistochemistry. RESULTS: COMP mRNA signals and immunoreactivity were strongly present in the cytoplasm of degenerating acinar cells in CP tissues as well as in CP-like lesions in pancreatic cancer tissues. In contrast, COMP expression was weak to absent in the cytoplasm of cancer cells in pancreatic cancer tissues, and in ductal cells and islet cells in normal pancreatic tissues. CONCLUSION: COMP is preferentially expressed in degenerating acinar cells in CP and in CP-like areas in pancreatic cancer, suggesting a potential role of this molecular in acinar cell dysfunction in CP.

Blotting, Northern↗

PubMed2003

Diagnosis and treatment of chronic pancreatitis.

OBJECTIVE: To summarize our experience in treatment of chronic pancreatitis (CP). METHODS: Clinical data on 245 patients with CP treated at our hospital from May 1983 to October 2001 were reviewed. RESULTS: Of the 245 patients, 122 suffered from CP for a year (49.8%) and 191 for 5 years (78.0%). The rate of positive diagnosis of B-ultrasound, CT, ERCP, B2-Ty-Para-aminobenzoic acid (PABA) for CP was 74.2%, 80.7%, 76.5% and 72.8%, respectively. 169 patients (69.0%) received surgical treatment. After the operation, 98.8% of the 169 patients experienced decreased pain with a complication rate of 1.2%. CONCLUSION: Early diagnosis and appropriate operative time and management are of vital importance in improving patients'quality of life and controlling the natural history of the disease.

Adolescent↗

PubMed2002

Surgical treatment of chronic pancreatitis.

OBJECTIVE: To summarize the experience in the surgical treatment of chronic pancreatitis. METHODS: 189 patients with pancreatitis admitted from May 1983 to August 1999 to our hospital were reviewed. RESULTS: 136 (72%) patients received surgical treatment including pancreatoduodenectomy (15 patients), distal pancreatectomy (12), internal drainage of pancreatic pseudocyst (28), side-to-side pancreaticojejunostomy (16), relief of biliary stenosis (58), and pancreatic biopsy (7). Pain was relieved in 97.8% of the patients, and the complication rate was 1.5%. CONCLUSIONS: It is crucial to select various surgical strategies at a proper time for chronic pancreatitis patients. Patients with chronic pancreatitis complicated by dilation or obstruction of the pancreatic duct or with biliary pancreatitis should be operated on in early stages, whereas those with other types of chronic pancreatitis should receive the therapy focusing on the alleviation of their symptoms, not on early surgical intervention. The timing and modality of surgery are important in improving the life quality of the patients and changing their natural history of the disease.

Adolescent↗

PubMedDate not supplied

Superstructure searching algorithm for generic reaction retrieval.

Chemical reaction knowledge is usually summarized and retrieved by chemists from references, journals, and reaction databases. To rigorously extract chemical reaction knowledge from large data sets, computer algorithms become much more important. This paper presents a new approach, superstructure searching (SSS) algorithm, for generic reaction retrieval. The algorithm considers all known reaction patterns from the targeted structure and assigns synthetic routes for new chemical compounds. This algorithm consists of screening, atom-by-atom comparison, and computation of R-groups' similarity.

Journal Article↗