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51.

Background

Pancreatic cancer is an aggressive malignancy with one of the worst mortality rates of all cancers. Recently, collapsin response mediator proteins (CRMPs) were reported to be associated with proliferation, apoptosis, differentiation, and invasion in several cancers. However, CRMP expression and their role in pancreatic cancer have not been investigated. This study aimed to clarify the clinical significance of CRMPs in pancreatic cancer.

Methods

Expression of crmp genes in 11 pairs of pancreatic cancer and corresponding noncancerous pancreas tissues were examined by real-time RT-PCR. Knockdown of CRMP4 expression using siRNA was examined in pancreatic cancer cell lines to determine whether CRMP4 regulates cell proliferation and invasion in vitro. Furthermore, CRMP4 protein levels in primary tumors of pancreatic cancer (n = 53) were examined by immunohistochemistry and compared with the clinicopathological features of the tumors.

Results

Of all the CRMPs, only CRMP4 was differentially expressed in pancreatic cancer tissues (p = 0.008). CRMP4 knockdown using siRNA reduced cellular invasion, but did not affect proliferation. The expression of CRMP4 was detected immunohistochemically in 34 (64.2 %) of the 53 pancreatic cancer samples, and CRMP4 expression was correlated with severe venous invasion (p = 0.044), stage (p = 0.019), and liver metastasis (p = 0.021). Multivariate analyses suggested that venous invasion and CRMP4 overexpression were prognostic factors for survival.

Conclusions

Our results suggested that CRMP4 is significantly associated with poor prognosis by promoting liver metastasis and can serve as a novel therapeutic target for pancreatic cancer.
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52.
Purpose. Age is known to be a major risk factor for adverse postoperative cognitive dysfunction after cardiac surgery. We conducted this study to determine if jugular venous oxygen saturation (SjvO2) differed during mild hypothermic (32°C) and normothermic cardiopulmonary bypass (CPB) in elderly patients.Methods. Sixty patients aged over 70 years who underwent elective coronary artery bypass grafting were randomly divided into two groups. Group 1 (n = 30) underwent normothermic CPB (>35°C) and group 2 (n = 30) underwent mild hypothermic CPB (32°C). For the continuous monitoring of SjvO2, a fiberoptic oximetry oxygen saturation catheter was inserted into the right jugular bulb after the induction of anesthesia. Hemodynamic parameters, and arterial and jugular venous blood gases were measured at seven time points.Results. The SjvO2 in the normothermic group was lower at the onset of CPB and 20min after the onset, than from the time of induction of anesthesia until the start of surgery (period 1), the respective SjvO2 values being 50.3% ± 1.0%, 50.1% ± 1.6%, and 59.5% ± 1.9% (P < 0.05). However, in the mild hypothermic group there were no changes in the SjvO2 value throughout the study. The cerebral desaturation time (when the SjvO2 value was <50%) and the ratio of the cerebral desaturation time to the total CPB time in the normothermic group differed significantly from those in the hypothermic group, being 19 ± 11min and 17% ± 10%, and 9 ± 3min and 8% ± 4%, respectively (P < 0.05).Conclusions. The SjvO2 value was better during mild hypothermic CPB than during normothermic CPB in elderly patients.  相似文献   
53.
A 49-year-old woman with Gardner's syndrome, who underwent total proctocolectomy in 1982, was found to have a cancer of the duodenal bulb. Subsequently, resection of the stomach and duodenal bulb was performed in 1983. The surgical specimen showed an ulcerating tumor in the duodenal bulb which was a moderately differentiated adenocarcinoma histologically. Multiple adenomas were present in the gastric antrum and the duodenum. Duodenal cancer so far reported has been mostly confined to the periampullary region, and cancer of the duodenal bulb associated with familial polyposis coli has not been reported.  相似文献   
54.
Fractures of the glenoid cavity that are substantially displaced are rare. A patient with shoulder pain and dysfunction caused by a severely malunited fracture of the glenoid cavity was treated successfully with corrective osteotomy and bone grafting. Functional results 2 years after surgery were satisfactory, and radiographs showed no evidence of degenerative change. Although appropriate initial management should prevent the development of symptomatic malunion, results of the current study suggest that later reconstruction of the glenoid cavity restores satisfactory function, even if so much time has elapsed that glenoid osteotomy must be done to achieve reduction.  相似文献   
55.
Pathoanatomy of posterior malleolar fractures of the ankle   总被引:5,自引:0,他引:5  
BACKGROUND: The functional outcome following ankle fractures that involve a posterior malleolar fragment is often not satisfactory, and treatment of this type of fracture remains controversial. Thorough knowledge of the pathologic anatomy of the posterior malleolar fracture is essential for planning appropriate treatment. Thus, we conducted a computed tomographic study to clarify the pathologic anatomy of the posterior malleolar fracture. METHODS: Between 1999 and 2003, fifty-seven consecutive patients with a unilateral ankle fracture with one or more posterior fragments were managed at our hospital. We reviewed the patients' preoperative computed tomographic scans to determine (1) the ratio of the posterior fragment area to the total cross-sectional area of the tibial plafond and (2) the angle between the bimalleolar axis and the major fracture line of the posterior malleolus. Each fracture was categorized according to the location of the major fracture line on the computed tomographic image at the level of the tibial plafond. RESULTS: The fifty-seven fractures were categorized into three types: (1) the posterolateral-oblique type (thirty-eight fractures; 67%), (2) the medial-extension type (eleven fractures; 19%), and (3) the small-shell type (eight fractures; 14%). Two of the eleven medial-extension fractures extended to the anterior part of the medial malleolus. A total of nine of the eleven medial-extension fractures actually consisted of two fragments [corrected] The conditions are not exclusive of one another; for example, in the case of one of the fractures exhibiting two fragments, the fracture also extended to the anterior part of the medial malleolus [corrected] The average area of the fragment comprised 11.7% of the cross-sectional area of the tibial plafond for posterolateral-oblique fractures and 29.8% for medial-extension fractures. In the cases of seven of the nine fractures that comprised >25% of the tibial plafond, the fracture line extended to the medial malleolus. The angles between the bimalleolar axis and the major fracture line of the posterior malleolus varied. CONCLUSIONS: The fracture lines associated with posterior malleolar fractures appear to be highly variable. A large fragment extending to the medial malleolus existed in almost 20% of the posterior malleolar fractures in the current study, and some fragments involved almost the entire medial malleolus. Because of the great variation in fracture configurations, preoperative use of computed tomography may be justified. The information obtained from this study will be helpful for conducting basic research of this condition and for determining appropriate surgical approaches.  相似文献   
56.
Periprocedural hemodynamic instability with carotid angioplasty and stenting   总被引:10,自引:0,他引:10  
Taha MM  Toma N  Sakaida H  Hori K  Maeda M  Asakura F  Fujimoto M  Matsushima S  Taki W 《Surgical neurology》2008,70(3):279-85; discussion 285-6
BACKGROUND: Carotid angioplasty and stenting is used for treatment of carotid stenosis. Stent deployment may induce HDI and thereby cause systemic or neurologic deficits. This study defines characteristics and predictors of HDI with CAS. METHODS: A total of 132 patients who had undergone CAS were evaluated for periprocedural and postprocedural HDI (hypertension, systolic blood pressure >160 mm Hg; hypotension, systolic blood pressure <90 mm Hg; or bradycardia, heart rate <60 beats per minute). RESULTS: Frequencies of HDI were 6.8% for hypertension, 32.6% for hypotension, and 15.9% for bradycardia. In addition, CAS of the right side (P < .01), carotid bulb lesions (P < .05), eccentric posterior carotid plaque (P < .0001), and general anesthesia (P < .05) were associated significantly with postprocedural HDI. Male sex (OR, 3.4; 95% CI, 1.8-67.2; P < .001), age of 80 years or older (OR, 0.4; 95%CI, 0.1-1.4; P = .011), and plaque ulceration (OR, 0.5; 95% CI, 0.1-9.5; P = .008) independently predicted postprocedural hypertension. Male sex (OR, 2.5; 95% CI, 1.3-24.9; P < .001), preprocedural major stroke (OR, 0.1; 95% CI, 0.01-0.8; P = .002), carotid bulb lesions (OR, 1.6; 95% CI, 1.1-25.9; P = .024), and contralateral carotid occlusion (OR, 0.6; 95% CI, 0.2-4.9; P = .040) all predicted postprocedural hypotension. Bradycardia was associated with diabetes mellitus (OR, 0.7; 95% CI, 0.3-2.4; P = .033), preprocedural TIA (OR, 1.7; 95% CI, 1.4-17.9; P = .020), and minor stroke (OR, 1.5; 95% CI, 1-10.9; P = .037). In 5 patients, HDI predisposed neurologic or systemic deterioration. CONCLUSIONS: Hemodynamic instability is common with CAS; hypotension and bradycardia are more frequent than hypertension. Some clinical, angiographic, and procedural variables can predict these HD changes.  相似文献   
57.

Two cases of atlantoaxial (A-A) instability that showed different MRI findings between supine and upright positions are presented. The upright MRI represented the findings corresponding to their symptoms. In A-A lesions, conventional MR images taken in the supine position do not always explain the pathophysiological consequences. The MR images taken in the upright position disclose the actual spinal pathophysiology with gravitational effects.

  相似文献   
58.

Background

Laparoscope manipulating robots are useful for maintaining a stable view during a laparoscopic operation and as a substitute for the surgeon who controls the laparoscope. However, there are several problems to be solved. A large apparatus sometimes interferes with the surgeon. The setting and repositioning is awkward. Furthermore, the initial and maintenance costs are expensive. This study was designed to develop a new laparoscope manipulating robot to overcome those problems.

Methods

We developed a compact robot applicable for various types of laparoscopic surgery with less expensive materials. The robot was evaluated by performing an in vitro laparoscopic cholecystectomy using extracted swine organs. Then, the availability of the robot to various operations was validated by performing a laparoscopic cholecystectomy, anterior resection of the rectum, and distal gastrectomy using a living swine. The reliability of the system was tested by long-time continuous running.

Results

A compact and lightweight laparoscope manipulating robot by the name of P-arm was developed. The surgical time of an in vitro laparoscopic cholecystectomy with and without the P-arm was not different. The three types of operations were accomplished successfully. During the entire procedure, the P-arm worked without trouble and did not interfere with the surgeons. Continuous 8-h operating tests were performed three times and neither discontinuance nor trouble occurred with the system.

Conclusions

The P-arm worked steadily for various swine operations, without interfering with surgeon’s work.  相似文献   
59.
There is a considerable variation in the histologic subtype of epithelial malignancies among carcinoma ex pleomorphic adenomas (CXPA) and virtually any known carcinoma entity can develop. To our knowledge, adenoid cystic carcinoma (AdCC) ex PA is quite rare despite the fact that de novo AdCC is the fourth most common salivary gland malignancy. We describe a new case of AdCC ex PA in the parotid gland of a 62 year-old woman. In our patient, there was a short interval of time between parotidectomy and local recurrence and rapid development of distant metastases. Although most of the reported cases are considered low-grade, evidence is presented here that AdCC can take the form of a high-grade malignancy in PA.  相似文献   
60.

Background

Postoperative hepatic insufficiency is a critical complication after extended hepatic resection in patients with biliary tract malignancies, the majority of whom suffer from obstructive jaundice. The aim of this study was to assess clinical parameters linked to this type of liver dysfunction.

Methods

A total of 111 patients were retrospectively reviewed. Patient background, pre- and intraoperative parameters, and a ratio of remnant liver volume/entire liver volume (RLV/ELV) as a volumetric parameter were compared between patients with and without postoperative hyperbilirubinemia and subsequent fatal outcome.

Results

Logistic regression indicated that only RLV/ELV ratio was an independent factor influencing postoperative hyperbilirubinemia, and RLV/ELV ratio and indocyanine green retention rate at 15 minutes (ICG-R15) were factors affecting survival. Patients with RLV/ELV less than 40% had 7.6 times the risk of postoperative hyperbilirubinemia, while no patients with RLV/ELV greater than 40% and ICG-R15 less than 25% died of liver failure.

Conclusions

The RLV/ELV ratio was the factor with the greatest impact on liver dysfunction after extended hepatectomy in patients with biliary tract malignancies.  相似文献   
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