[Individualized surgical treatment and prognosis of intraductal papillary mucinous neoplasms of the pancreas].

OBJECTIVE: To investigate the clinical manifestation, individualized surgical treatment, and prognosis of intraductal papillary mucinous neoplasms (IPMN) of pancreas. METHODS: The clinical data of 56 IPMN cases treated between January 2007 and December 2011 was retrospectively analyzed. Among the 56 patients (38 male and 18 female, mean age (61 ± 7) years), 26 were main-duct type, 18 were branch-duct type, 12 were mixed type. Pancreatectomy was performed on 48 cases, including pancreaticoduodenectomy on 29 patients, distal pancreatectomy on 17 patients, and total pancreatectomy on 2 patients. RESULTS: The overall postoperative morbidity rate was 27.1% (13/48), there was no perioperative mortality. Pathology showed 31 cases of noninvasive IPMN, 17 cases of invasive IPMN, and 7 cases of lymph node metastasis. The rate of invasive tumors was 46.2% (12/26) in main duct type, 3/12 in mixed type, and 2/18 in branch duct type IPMN, the difference was statistically significant (χ(2) = 6.385, P = 0.041). The five-year survival rate for patients with noninvasive and invasive neoplasms was 100% and 24.6%, respectively. The prognosis of invasive cases with lymph node metastasis was significantly worse than those without lymph node metastasis (P = 0.017). A regular follow-up without surgical treatment was performed on 8 cases with asymptomatic side branch IPMN less than 3 cm in diameter, and no progression was found during the follow-up. CONCLUSIONS: IPMN has a relative good prognosis. Main duct type and mixed type IPMN have a higher malignant potential, and should receive a surgical treatment. Patients of branch duct type IPMN with a <3 cm diameter lesion and no clinical manifestations can be managed with close follow-up only.

[The diagnosis and management strategies for gastrointestinal hemorrhage following pancreaticoduodenectomy].

OBJECTIVE: To analyze the causes and clinical features of gastrointestinal hemorrhage following pancreaticoduodenectomy (PD), and to provide the management strategies for this complication. METHODS: The clinic data of 412 patients who underwent PD from January 2000 to April 2010 was retrospectively reviewed. There were 232 male and 180 female patients, average age was (60 ± 12) years. The mode of procedure was standard PD and the Child's reconstruction of digestive tract, whose anastomosic steps encluded gastroenterostomy following chlangioenterostomy and pancreaticoenterostomy, was employed. Etiology of gastrointestinal haemorrhage, diagnostic methods and treatment strategy was recorded and analyzed. RESULTS: The postoperative mobidity was 37.1% (153/412), the rate of haemorrhagic complications was 6.6% (27/412), and gastrointestinal hemorrhage was recorded in 11 patients (2.7%). The bleeding rate of pancreaticointestinal anastomosis and gastricointestinal anastomosis were 5/11 and 4/11, respectively. Among these 11 patients, early hemorrhage occurred in 6 patients, 7 patients were due to technical failure. In order to control this kind of complication, open abdominal operation alone was performed on 4 patients, endoscopic management was performed on 3 patients and succeeded in 2 patients, vascular interventional therapy was performed on 5 patients and succeeded in 2 patients, and Re-laparotomy following vascular interventional therapy was performed on 2 patients successfully. CONCLUSIONS: Gastrointestinal hemorrhage following PD always occurred in early stage and reliable hemostasis during operation is the key points for prevention. Angiography is minimally invasive and holds the diagnostic value. Timely and decisive reoperation is an important method to management of postoperative gastrointestinal hemorrhage.

Facile large-scale synthesis of monodisperse mesoporous silica nanospheres with tunable pore structure.

Mesoporous silica nanoparticles (MSNs) are experiencing rapid development in the biomedical field for imaging and for use in heterogeneous catalysis. Although the synthesis of MSNs with various morphologies and particle sizes has been reported, synthesis of a pore network with monodispersion control below 200 nm is still challenging. We achieved this goal using mild conditions. The reaction occurred at atmospheric pressure with a templating sol-gel technique using cetyltrimethylammonium (CTA(+)) as the templating surfactant and small organic amines (SOAs) as the mineralizing agent. Production of small pore sizes was performed for the first time, using pure and redispersible monodispersed porous nanophases with either stellate (ST) or raspberry-like (RB) channel morphologies. Tosylate (Tos(-)) counterions favored ST and bromide (Br(-)) RB morphologies at ultralow SOA concentrations. Both anions yielded a worm-like (WO) morphology at high SOA concentrations. A three-step formation mechanism based on self-assembly and ion competition at the electrical palisade of micelles is proposed. Facile recovery and redispersion using specific SOAs allowed a high yield production at the kilogram scale. This novel technique has practical applications in industry.