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Measuring deep brain neural activities with a microelectrode is of greatest importance in uncovering the mechanism of various brain disorders. In this operation, a microelectrode needs to be accurately inserted into deep the brain. However, a microelectrode of high flexibility would bend at encountering a layer of tough tissue during insertion, which would lead to deflection and impaired targeting accuracy. To deal with this problem, a rotational insertion method has been developed in this paper for deflection-free insertion. Rotation helps generate a dynamic anti-bending force to prevent buckling, and this force becomes larger with the increase of rotational speed. Thus, by controlling the rotational speed at which insertion is carried out, deflection-free insertion of a microelectrode deep into brain can be realized. The effectiveness of this method has been experimentally confirmed.

In order to prepare natural anti-mosquito agent, the volatile oil was extracted from artemisia argyi by three-step of water extraction, steam distillation and organic solvent extraction. Three factors have been optimized. They were material/liquid ratio, distillation time and crushing particle size having influence on the extraction efficiency. The experimental results showed as: the optimum extraction process was that material/liquid ratio for 1:20, distillation time for 4 hours and crashing particle size for 40 meshes. At optimized extraction process condition, the extraction efficiency was 0.71%. Chemical constituents were determined by gas chromatography-mass spectrometry apparatus (GC-MS). They were mainly single terpenoids and its derivatives, including monocylic single terpenoids and 2-ring single terpenoids. Primary components were eucalyptol, camphor, camphene, borneol and so on. This provided good foundation for preparation of anti-mosquito and anti-insect agent.

Although non-steroidal anti-inflammatory drugs (NSAIDs) have been demonstrated to have cancer-preventive effects and induce apoptosis of cancer cells, the mechanism of their effects is not clearly known. We studied the mechanism in human esophageal cancer cell line TE13. The esophageal squamous cell carcinoma cell line TE-13 was cultured with NS-398 at different concentrations or for different times. Proliferation and apoptosis were measured by MTT reduction and flow cytometry. Prostaglandin F(1alpha) was determined with radioimmunoassay. Expression of COX-2 mRNA was measured by RT-PCR and COX-2 protein levels with Western blot analysis. Nuclear NF-kappaB and cytoplasmic IkappaB protein levels were determined by electrophoretic mobility shift assay and Western blot, respectively. NS-398 significantly inhibited cell proliferation and induced apoptosis at concentrations of 0.001, 0.01, 1, and 100 micromol/L. NS-398 dose-dependently decreased the levels of COX-2 mRNA, COX-2 protein, nuclear NF-kappaB protein and production of PGF(1alpha) and increased the cytoplasmic IkappaB protein. In conclusion, NS-398 inhibits the proliferation of, and induced apoptosis in, the cultured TE-13 SCC cell line. These changes correlate with a reduction in COX-2 mRNA and protein expression, prostaglandin synthesis, an inhibition of NF-kappaB nuclear translocation, and an increase in cytoplasmic IkappaB.

Our previous study showed that aspirin induced apoptosis of esophageal cancer cells in vitro by inhibiting the pathway of NF-kappaB downstream regulation of cyclooxygenase-2. The purpose of this study was to determine if similar changes occurred in vivo in the tumors of patients with SCC of the esophagus who were given a preferential COX-2 inhibitor, meloxicam. Fifty-three patients who had an esophagectomy for SCC were allocated randomly to either a Treatment group (n = 25) or a control group (n = 28). Patients in the Treatment group were given 7.5 mg/day of meloxicam, for between 10 and 14 days before surgery. Patients in the control group did not take any type of NSAID during this time interval. Samples of the tumor taken from the resected specimens were collected. Proliferation and apoptosis were measured by flow cytometry. The concentration of 6-keto-prostaglandin F(1)alpha in cancer tissue was determined by radio-immuno-assay. Expression of COX-2 mRNA was measured with RT-PCR and COX-2 protein levels with Western blot analysis. Nuclear NF-kappaB and cytoplasmic I kappaB protein levels were determined by electrophoretic mobility shift assay and Western blot, respectively. There were significantly more apoptotic cells in the tumors of patients who were using meloxicam. It also decreased the levels of COX-2 mRNA, COX-2 protein and nuclear NF-kappaB protein and increased the cytoplasmic I kappaB protein in the cancer. We conclude that meloxicam induces apoptosis in SCC of the esophagus in vivo by inhibiting the pathway of NF-kappaB downstream regulation of COX-2.

Deep brain stimulation (DBS) is an established surgical therapy for treatment of a number of neurological and neuropsychiatric disorders based on the modulation of neuronal firing deep in the brain. However, the delicate surgical operation and extremely expensive cost of the current DBS technology impede its wide applications. For non-invasive brain stimulation, transcranial magnetic stimulation and transcranial direct current stimulation have been tried in various therapeutic applications with little success due to two major imitations with their applied electromagnetic field: 1) the field does not focus on targeted brain functional sites, and 2) the field penetration depth is too shallow to be effective in stimulating targeted brain functional sites. In this paper, a novel magnetic field projector (MFP) capable of magnetically inducing deep brain modulation of neuronal firing is presented. The MFP projects a focused magnetic field to deep brain regions while suppressing the field on the scalp. The field penetration depth can be adjusted by configuring the structure parameters of the device as well as the excitation pulse current amplitude. An MFP prototype has been developed and tested on rats to modulate upward the neuronal firing frequency at the brain functional site ventrolateral preoptic nucleus for sleep induction, with the brain responses measured by EEG. The results showed that EEG sleep spindles were induced by a train of 9 Hz magnetic stimulation pulses for 10 s.

Increased cyclooxygenase-2 expression has been reported to be a poor prognostic indicator in a number of cancers. In this study we investigated the relationship between COX-2 expression in squamous cell carcinoma of the esophagus and tumor characteristics and patient survival. The study group consisted of 90 men and 48 women who underwent esophagectomy for squamous cell carcinoma of the esophagus between October 1984 and May 1985. COX-2 expression was measured by immunohistochemistry in 138 primary cancers, 23 metastatic lymph nodes and 21 normal esophageal stumps. The relationship between the extent of staining for COX-2 and clinicopathological features and survival was determined. The extent of staining for COX-2 in both primary and metastatic cancers was higher than in normal squamous epithelia (P = 0.002 and P < 0.0001 respectively), and the grade of staining in the primary tumor correlated positively with the finding of lymph node metastases (P = 0.03). The 5-year survival rate in patients with less than 10% COX-2 positive cells was 47.5% compared to 23.2% in patients with more than 10% COX-2 positive cells (P = 0.0036). The relationship between survival and COX-2 staining was not due to COX-2 being a surrogate marker for TNM stage. Our results show that the expression of COX-2 is elevated in squamous cell carcinoma of the esophagus compared to normal epithelium and correlates with lymph node metastases. Survival was longer in those patients whose tumors expressed lower levels of COX-2.

Objective To investigate the clinical and pathologic features of rectal gastrointestinal stromal tumors (GIST) and to evaluate their reasonable management.

To explore the relevant factors influencing sentinel and non-sentinel lymph node (SLNM, NSLNM) metastases in breast cancer.The clinicopathological data of 283 women with breast cancer who underwent sentinel lymph node biopsy from July 2010 to August 2011 in the Cancer Institute and Hospital at Chinese Academy of Medical Sciences were reviewed retrospectively, and the relevant factors affecting sentinel and non-sentinel lymph node metastases were analyzed.Univariate analysis showed that age, menopause status, tumor size, pathological type and intravascular tumor thrombus were associated with SLNM metastasis (all P0.05). Multivariate analysis showed that age, tumor size and intravascular tumor thrombus were associated with SLNM (all P0.05) . No risk factors were found in either univariate or multivariate analysis of NSLNM.Age, tumor size and intravascular tumor thrombus are independent influencing factors associated with SLNM, and age is a protective factor. Whether ER, pathological type and pathological grade are associated with SLNM or not is still controversial.

To investigate the prognostic implication of common bile duct infiltration in the adenocarcinoma of the ampulla of Vater after panreaticoduodenectomy.A retrospective study was conducted on clinical manifestation, pathological behavior and survival data in 102 patients with Vater's ampulla adenocarcinoma, who underwent pancreaticoduodenectomy from Jan 1980 to Dec 2003. The result of patients with the common bile duct infiltration were compared with that of those without.There were 42 cases in stage I (41.2%), 32 in stage II (31.3%), 27 in stage III (26.5%), and 1 in stage IV (1.0%). As for T stage: 9 cases in stage T1 (8.8%), 40 in T2 (39.2%), 25 in T3 (24.5%), and 28 in T4 (27.5%). As regarding to N stage: 76 cases in stage N0 (74.5%) and 26 in N1 (25.5%). Of these 102 cases, microscopic infiltration in the common bile duct (25.0%) was identified in 26 cases. A significant difference was observed between the patients with bile duct infiltration and those without, in the proportion of pancreatic medullae infiltration: 84.6% (infiltration group) versus 34.2% (non-infiltration group, P0.001). Twenty-five cases (24.5%) had recurrence and/or metastases postoperatively, with a median survival of 20 months (range, 2 to 93 months). The overall median survival of the whole group was 46.0 months (2 approximately 192 months), with a significant difference between the common bile duct infiltration group (36 months) and the non-infiltration group (49 months, P = 0.0061). The median non-recurrence survival of the whole group was 43 months (2 approximately 192 months), and a significant difference was observed between the common bile duct infiltration group (35 months) and non-infiltration group (47 months, P = 0.0002).If the adenocarcinoma of the Vater's ampulla infiltrated the common bile duct, the invasion to the pancreatic medulla is likely developed, and usually with a poor non-recurrence and overall survival. Therefore, postoperative chemotherapy/radiotherapy is suggested.

We examined the effect of aspirin on survival following resection for squamous cell carcinoma (SCC) of the esophagus or adenocarcinoma of the gastric cardia. Patients who underwent esophagectomy for these cancers between May 2000 and December 2002 were allocated to one of three groups and given daily either a low dose of aspirin, placebo, or no tablets. The 5-year survival for all patients on aspirin (445) was 51.2%, placebo (658) 41%, and no tablet (495) 42.3% (P = 0.04 for difference between treatments). The 5-year survival for all SCC patients on aspirin (267) was 49.8%, placebo (433) 42.2%, and no tablet (343) 41.2% (P = 0.26). There was a significant improvement in survival for patients with adenocarcinoma of the cardia on aspirin compared with the two control groups combined (P = 0.029). Survival for T2N0M0 SCC patients was significantly improved with aspirin (71) compared with placebo (167) or no tablet (134) (P = 0.0004). However, there was no significant difference between the survival curves for T2N0M0 adenocarcinoma patients on aspirin (21) and the two control groups combined (65) (P = 0.29). The results of this preliminary study support further investigation of aspirin as adjuvant therapy to improve survival in subsets of postesophagectomy patients.

To investigate the clinical-pathological characteristics and surgical prognosis of malignant tumor of pancreatic body and tail.A retrospective study was accomplished on clinical manifestation, pathological behavior and postoperative survival in 106 patients with malignant tumor of pancreatic body and tail in single institution from Jan 1980 to Dec 2003, and compared these with 451 patients with malignant pancreatic cancer.There were significant differences in the following parameters (malignant tumor of the body and tail vs those of the head) between the two tumors: (1) the complaints of pain (0.74:41, chi(2) = 37.035, P0.01) and jaundice (0.04:0.75, chi(2) = 155.509, P0.01); (2) serum SGPT [(27.33 +/- 3.98) U/L: (118.60 +/- 4.59) U/L, F = 89.351, P0.01], total bilirubin [(1.46 +/- 0.46) mg/dl: (14.11 +/- 0.60) mg/dl, F = 105.341, P0.01] and albumin [(4.20 +/- 0.45) g/L: (3.91 +/- 0.03) g/L, F = 26.642, P0.001]; (3) CEA (0.40:0.24, chi(2) = 6.148, P = 0.046) and CA-19-9 positive rate (0.57:0.86, chi(2) = 24.132, P0.01); (4) the concomitant total metastasis (0.38:0.20, chi(2) = 14.266, P0.01), including liver metastasis (0.30:0.17, chi(2) = 9.003, P0.01). Postoperative median survival, resection of non-metastatic pancreatic body and tail cancer was longer than resection of metastatic disease significantly (15 vs 7 months,chi(2) = 21.63, P0.01), which the latter was the same as those who didn't remove (6 months,chi(2) = 0.22, P = 0.64).The predominant problem is distant metastasis (especially liver metastasis) in the malignant tumor of the body and tail of the pancreas in comparison with pancreatic head cancer. Resection of the body and tail could not increase postoperative survival if metastasis exists. The major way to improve the prognosis is to prevent and manage the distant metastasis.

To investigate the risk factors for local recurrence and distant metastasis after radical anterior resection for rectal cancer.Clinicopathological data of 957 patients who underwent radical anterior resection for rectal cancer from 1983 to 2000 were reviewed retrospectively. The risk factors for local recurrence and distant metastasis were analyzed.There were 150 recurrent or metastatic cases (15.7%) after radical resection during a median follow- up of 71 months. Recurrence and metastasis sites included pelvics(6.0%, n=57), liver (4.9%, n=47), lung (4.2%, n=40) and other sites (0.6%, n=6). The median recurrent interval was 18 months (2-85 months),with a median survival of 8 months (1-62 months) after recurrence. Re-resection of the tumors was performed in 23 patients(15.3% ), and the median survival of such patients was 30 months with a 5- year survival rate of 13.0%. There were significant differences in recurrence and metastasis considering age,family history of tumor,CEA level,T staging,lymph node metastasis,venous cancerous emboli and signet cell carcinoma or mucinous adenocarcinoma. Logistic regression analysis revealed that family history (P=0.001), high CEA level (P=0.033), T3- 4 (P=0.000), lymph node metastasis (P=0.000),venous cancerous emboli (P=0.001),and signet cell carcinoma or mucinous adenocarcinoma (P=0.012) were risk factors for recurrence and metastasis.There are several risk factors for recurrence after radical anterior resection for rectal cancer. The main recurrent or metastatic sites are pelvis,liver and lung. Resection of recurrent tumor can prolong the survival.

To investigate the therapeutic principles and prognosis of synchronous primary colorectal carcinomas (SCC).The data of 66 SCC patients surgically treated from 1984 to 2003 were retrospectively reviewed.The synchronous primary colorectal carcinomas were diagnosed and resected simultaneously in 65 patients except one that was misdiagnosed. Thirty patients underwent combined resection, 35 patients segmental resection. Sixty-two patients received radical resection, while three patients had palliative resection due to hepatic metastasis. The overall postoperative 3-, 5-, 10-year survival rates were 70.3%, 60.0%, 40.6%, respectively. In the patients who had simultaneous radical resection, the 3-, 5-, 10-year survival rates were 76.0%, 65.9%, 46.4% respectively.The extent of resection should be individually determined by the lesion location, extent and distance between the lesions, as well as the patient's general condition. More extensive bowel resection, such as total or subtotal colectomy are suggested for those patients with hereditary nonpolyposis colorectal carcinoma syndrome in order to reduce or avoid the risk of metachronous colorectal carcinoma. The postoperative survival in patients with synchronous primary colorectal carcinoma is similar to those with solitary lesion.

To analyze the differences and relationships among periampullary cancers.A retrospective study was accomplished on the clinical manifestation, pathological behavior and postoperative survival of 631 patients with periampullary cancer hospitalized from Jan 1980 to Dec 2003.The characteristics of different periampullary cancers, in the order of carcinoma of head of pancreas (n = 352), carcinoma of common bile duct (n = 42), carcinoma of Vater's ampulla (n = 189), and duodenal cancer (n = 48) were as follows: (1) the mean duration of symptoms were 11.9 +/- 1.3, 5.8 +/- 0.9, 6.3 +/- 0.6, and 18.3 +/- 4.0 weeks (F = 6.18, P0.01); (2) the serum total bilirubin was 225 +/- 10, 345 +/- 35, 235 +/- 13, and 50 +/- 13 micromol/L(chi(2) = 68.49, P0.01); (3) the mean tumor size was 6.0 +/- 2.2, 3.0 +/- 1.3, 3.0 +/- 1.9, and 4.8 +/- 3.9 cm respectively (chi(2) = 255.7, P0.01); (4) adenocarcinoma accounted for 88%. Distant metastasis occurred in 98 cases, mostly to liver, abdominal cavity, and omentum. Local invasion mainly occurred in duodenum (chi(2) = 10.76, P0.01), common bile duct (chi(2) = 15.16, P0.01), and periampullary tissues (chi(2) = 22.49, P0.01), and great vessels (chi(2) = 51.25, P0.01). (5) the T staging (chi(2) = 11.68, P0.01) and lymph node status (chi(2) = 8.33, P0.05) of the removed tumor specimens were different among different kinds of carcinomas; (6) local invasion of duodenum (chi(2) = 10.76, P0.01), common bile duct (chi(2) = 15.16, P0.001), periampullary tissues (chi(2) = 22.49, P0.01), and great vessel (chi(2) = 51.25, P0.01) occurred in unresectable carcinomas; (7) the resection rates were 13% (n = 46), 50% (n = 21), 74% (n = 139), and 56% (n = 27) respectively (chi(2) = 205.6, P0.01); (8) the postoperative median survival periods were 6.0 +/- 0.3, 13.0 +/- 1.2, 22.0 +/- 1.6, and 13.0 +/- 2.5 months respectively (chi(2) = 173.47, P0.01).Different tumor has its predominant clinical manifestation, pathological character, the probability of resection, and postoperative median survival. The prognosis after surgical treatment may be decided by biological behavior of tumor itself.