Monocyte chemoattractant protein-1 (MCP-1) deficiency enhances alternatively activated M2 macrophages and ameliorates insulin resistance and fatty liver in lipoatrophic diabetic A-ZIP transgenic mice.

AIMS/HYPOTHESIS: Monocyte chemoattractant protein-1 (MCP-1)/chemokine (C-C motif) ligand (CCL) 2 (CCL2) secreted from white adipose tissue (WAT) in obesity has been reported to contribute to tissue macrophage accumulation and insulin resistance by inducing a chronic inflammatory state. MCP-1 has been shown to be elevated in the fatty liver of lipoatrophic A-ZIP-transgenic (A-ZIP-Tg) mice. Treatment of these mice with the CC chemokine receptor (CCR) 2 antagonist has been shown to ameliorate the hyperglycaemia, hyperinsulinaemia and hepatomegaly, in conjunction with reducing liver inflammation. However, since CCR2 antagonists can block not only MCP-1 but also MCP-2 (CCL8) and MCP-3 (CCL7), it remains unclear whether MCP-1 secreted from the liver could contribute to hyperglycaemia, hyperinsulinaemia and hepatomegaly in conjunction with liver inflammation, as well as to the M1 and M2 states of macrophage polarisation. METHODS: To address these issues, we analysed the effects of targeted disruption of MCP-1 in A-ZIP-Tg mice. RESULTS: MCP-1 deficiency alone or per se resulted in a significant amelioration of insulin resistance in A-ZIP-Tg mice, which was associated with a suppression of extracellular signal-regulated protein kinase (ERK)-1/2 and p38 mitogen-activated protein kinase (p38MAPK) phosphorylation in liver. Although MCP-1 deficiency did not reduce the expression of macrophage markers, it increased the expression of the genes encoding M2 macrophage markers such as Arg1 and Chi3l3, as well as significantly reducing the triacylglycerol content of livers from A-ZIP-Tg mice. CONCLUSIONS/ INTERPRETATION: Our data clearly indicated that MCP-1 deficiency improved insulin resistance and hepatic steatosis in A-ZIP-Tg mice and was associated with switching macrophage polarisation and suppressing ERK-1/2 and p38MAPK phosphorylation.

Practice and yield of early CT scan in acute pancreatitis: a Dutch Observational Multicenter Study.

BACKGROUND: Early computed tomography (CT) (within 4 full days after symptom onset) may be performed to distinguish acute pancreatitis (AP) from other intra-abdominal conditions or to identify early pancreatic necrosis. We analyzed practice and yield of early CT in patients with an established clinical diagnosis of AP in a Dutch cohort (EARL study). METHODS: Multicenter observational study. Etiology, disease course, CT timing, Balthazar CT score, and clinical management were evaluated. RESULTS: First documented hospital admissions of 166 patients were analyzed. Etiology was biliary (42.8%), unknown (20.5%), alcoholic (18.1%), post-endoscopic retrograde cholangiopancreatography (11.4%), and miscellaneous (7.2%). In 89.2% (148/166), the disease course was mild. Out of 18 patients with severe AP, 11 eventually developed (peri)pancreatic necrosis. At least one CT (range 1-12) was performed in 47% (78/166) of all patients and in 62.8% (49/78) it was acquired within 4 full days after symptom onset. Practice, timing, and Balthazar CT score of early CTs were not significantly different between mild and severe AP. None of the early CTs showed necrosis and no alternative diagnoses were established. In 89.8% (44/49), clinical management was not altered after early CT. In 10.2% (5/49), prophylactic antibiotics were started, but in absence of necrosis. CONCLUSIONS: A CT scan was frequently acquired early in the course of AP, but its yield was low and had no implications with regard to clinical management. It seems prudent that clinicians should be more restrictive in the use of early CT, in particular in mild AP, to prevent unnecessary radiation exposure and to save costs.

The yield of first-time endoscopic ultrasonography in screening individuals at a high risk of developing pancreatic cancer.

OBJECTIVES: Approximately 10-15% of all pancreatic cancers (PCs) may be hereditary in origin. We investigated the use of endoscopic ultrasonography (EUS) for the screening of individuals at high risk for developing PC. In this paper the results of first-time screening with EUS are presented. METHODS: Those eligible for screening in this study were first-degree family members of affected individuals from familial pancreatic cancer (FPC) families, mutation carriers of PC-prone hereditary syndromes, individuals with Peutz-Jeghers syndrome, and mutation carriers of other PC-prone hereditary syndromes with clustering (> or =2 cases per family) of PC. All individuals were asymptomatic and had not undergone EUS before. RESULTS: Forty-four individuals (M/F 18/26), aged 32-75 years underwent screening with EUS. Thirteen were from families with familial atypical multiple-mole melanoma (FAMMM), 21 with FPC, 3 individuals were diagnosed with hereditary pancreatitis, 2 were Peutz-Jeghers patients, 3 were BRCA1 and 2 were BRCA2 mutation carriers with familial clustering of PC, and 1 individual had a p53 mutation. Three (6.8%) patients had an asymptomatic mass lesion (12, 27, and 50 mm) in the body (n=2) or tail of the pancreas. All lesions were completely resected. Pathology showed moderately differentiated adenocarcinomas with N1 disease in the two patients with the largest lesions. EUS showed branch-type intraductal papillary mucinous neoplasia (IPMN) in seven individuals. CONCLUSIONS: Screening of individuals at a high risk for PC with EUS is feasible and safe. The incidence of clinically relevant findings at first screening is high with asymptomatic cancer in 7% and premalignant IPMN-like lesions in 16% in our series. Whether screening improves survival remains to be determined, as does the optimal screening interval with EUS.

[Surgical drainage of the pancreatic duct in patients with chronic pancreatitis is more effective than endoscopic drainage: randomized trial]. / Chirurgische drainage van de ductus pancreaticus bij patiënten met chronische pancreatitis effectiever dan endoscopische drainage: gerandomiseerde trial.

OBJECTIVE: To compare endoscopic and surgical drainage of the pancreatic duct for ductal decompression in patients with severe pain due to chronic pancreatitis and a dilated pancreatic duct. DESIGN: Randomized clinical trial. METHOD: All symptomatic patients with chronic pancreatitis and a distal obstruction of the pancreatic duct, but without an inflammatory mass, were eligible for this study. Patients were randomized to endoscopic transampullary pancreatic duct drainage or to operative pancreaticojejunostomy. The primary end point was the average Izbicki pain score, measured during 2 years of follow-up. The secondary endpoints were pain relief at the end of follow-up, physical and mental health, morbidity, mortality, hospital stay and number of procedures performed. RESULTS: Of 118 patients who were evaluated between January 2000-October 2004 39 patients were randomized; 19 were treated endoscopically (16 of whom underwent lithotripsy) and 20 by operative pancreaticojejunostomy. During 24 months of follow-up, compared with endoscopic drainage, surgery was associated with lower Izbicki pain scores (51 versus 25; p < 0.001) and better SF-36 physical health summary scores (p = 0.003). Furthermore, at the end of follow-up, pain relief was achieved in 32% of patients randomized to endoscopic drainage and 75% of patients randomized to surgical drainage (p = 0.007). Complication rates and hospital stay were similar, but endoscopic treatment required more procedures (median 8 versus 3; p < 0.001).

Ten-year follow-up results of a randomised controlled study comparing level-I vs level-III axillary lymph node dissection for primary breast cancer.

The most appropriate level of axillary dissection for breast cancer remains unclear. The present randomised study compared the treatment results of level-I vs level-III dissection in T1/2/3 and N0/1a/1b (1987 UICC classification) breast cancer without distant metastasis. Between 1995 and 1997, 522 patients were enrolled, and 514 were eligible. They were stratified into breast-conserving surgery or mastectomy, and then further stratified into level-III dissection (group-A, n=258) or level-I dissection (group-B, n=256). All patients were given oral 5-fluorouracil at 200 mg day-1 and tamoxifen at 20 mg day-1, daily for 2 years. Group-A resulted in a significantly longer operation time (77.0 vs 60.5 min, P<0.0001) and significantly larger blood loss (62.1 vs 48.1 ml, P<0.0001) than group-B, but in no significant differences in the frequencies of arm oedema and shoulder disturbance. Group-A resulted in a significantly larger number of dissected nodes than group-B (18.7 vs 14.8, P<0.0001), but in no differences in the number of involved nodes (1.54 vs 1.44). There were no significant differences in the 10-year overall and disease-free survival rates: 89.6 and 76.6% for group-A vs 87.8 and 74.1% for group-B, respectively. In conclusion, level-III dissection resulted in a longer operation time and greater blood loss than level-I, but did not improve the survival rate. Level-III dissection is not a recommended surgery for T1-3/N0-1b breast cancer.

Influence of the rate of contrast change on the quality of contrast sensitivity assessment: a comparison of three psychophysical methods.

Criterion-free forced-choice procedures for measuring contrast sensitivity with a cathode ray tube (CRT) have low within-subject, intersubject, and test-retest variabilities, but a long test time compared with psychophysical methods that rely on the subject's criterion to determine threshold. Test time and variability of criterion-dependent methods depend on the rate at which the contrast changes on the CRT display. This study compared two criterion-dependent psychophysical methods for measuring contrast sensitivity (the method of increasing contrast and the von Békésy tracking method) with a criterion-free two-alternative forced-choice procedure. A range of rates of contrast change was studied: 0.1, 0.3, 0.5, 0.7 and 1.0 log unit s-1. Contrast sensitivity, within-subject variability, intersubject variability, test-retest variability, and test time of the three methods were compared. The 2-AFC procedure performed best with regard to within-subject, intersubject, and test-retest variabilities. A time-efficient alternative was the von Békésy tracking method at rates between 0.1 and 0.5 log unit s-1.

Segmentation and size measurement of polyps in CT colonography.

Virtual colonoscopy is a relatively new method for the detection of colonic polyps. Their size, which is measured from reformatted CT images, mainly determines diagnosis. We present an automatic method for measuring the polyp size. The method is based on a robust segmentation method that grows a surface patch over the entire polyp surface starting from a seed. Projection of the patch points along the polyp axis yields a 2D point set to which we fit an ellipse. The long axis of the ellipse denotes the size of the polyp. We evaluate our method by comparing the automated size measurement with those of two radiologists using scans of a colon phantom. We give data for inter-observer and intra-observer variability of radiologists and our method as well as the accuracy and precision.

Spherical and irregular aberrations are important for the optimal performance of the human eye.

Contrast sensitivity measured psychophysically at different levels of defocus can be used to evaluate the eye optics. Possible parameters of spherical and irregular aberrations, e.g. relative modulation transfer (RMT), myopic shift, and depth of focus, can be determined from these measurements. The present paper compares measured results of RMT, myopic shift, and depth of focus with the theoretical results found in the two eye models described by Jansonius and Kooijman (1998). The RMT data in the present study agree with those found in other studies, e.g. Campbell and Green (1965) and Jansonius and Kooijman (1997). A new theoretical eye model using a spherical aberration intermediate between those of the eye models described by Jansonius and Kooijman (1998) and an irregular aberration with a typical S.D. of 0.3-0.5 D could adequately explain the measured RMT, myopic shift, and depth of focus data. Both spherical and irregular aberrations increased the depth of focus, but decreased the modulation transfer (MT) at high spatial frequencies at optimum focus. These aberrations, therefore, play an important role in the balance between acuity and depth of focus.

Inoculation of human interleukin-17 gene-transfected Meth-A fibrosarcoma cells induces T cell-dependent tumor-specific immunity in mice.

OBJECTIVE: The biological activities of interleukin-17 (IL-17), a newly cloned cytokine, have not been fully elucidated. The present study was designed to assess the in vitro and in vivo effect of transfecting the IL-17 gene into tumor cells. METHODS: A complementary DNA (cDNA) encoding human IL-17 (hIL-17) was obtained by polymerase chain reaction amplification from the human CD4+ T cell cDNA library and inserted into the plasmid pRc/cytomegalovirus to construct an expression vector for the hIL-17 gene. Murine Meth-A fibrosarcoma cells were transfected with the hIL-17 gene using the lipofectin method. The hIL-17 gene-expressing clone (Meth-A/IL-17) was selected and analyzed for cytokine expression by Northern blot. RESULTS: There was no significant difference in the in vitro proliferation rate among parent Meth-A, cells transfected with vector alone and Meth-A/IL-17 cells. When the tumor cells were transplanted subcutaneously into BALB/c nude (nu+/nu+) mice, there was no difference in in vivo growth rates among the three cell lines. Challenge with tumor cells in conventional BALB/c mice, however, resulted in the rejection of Meth-A/IL-17 cells, but the other two lines did grow. After immunization with Meth-A/IL-17 cells, the mice were rechallenged by parent Meth-A or syngeneic MOPC-104E plasmacytoma cells; the immunized mice rejected the Meth-A cells, but not the MOPC-104E cells. Injecting the anti-thy 1,2 (CD90), anti-CD4 or anti-CD8 monoclonal antibody into conventional BALB/c mice resulted in the resumption of in vivo growth of Meth-A/IL-17 cells, but injecting the anti-asialo GM1 antibody did not. Furthermore, flow cytometric analysis demonstrated a significant increase in the expression of major histocompatibility complex (MHC) class I and class II antigens and lymphocyte function-associated antigen-1 on Meth-A/IL-17 cells. CONCLUSION: Meth-A cells transfected with the hIL-17 gene can induce tumor-specific antitumor immunity by augmenting the expression of MHC class I and II antigens, and both CD4+ and CD8+ T cells may play important roles in inducing antitumor immunity, suggesting the possibility of developing a tumor vaccine incorporating IL-17-transfected tumor cells.

Heterogeneic distribution of thymidine phosphorylase between primary tumors and metastatic lesions of human pancreatic ductal carcinoma: implications for the efficacy of chemotherapy with 5-FU or its derivatives.

PURPOSE: It has been suggested that the expression of thymidine phosphorylase (TdRPase) correlates with the malignant potential of various cancers, but its involvement in human invasive ductal carcinoma (IDC) of the pancreas has not been reported. In the present study, the distribution and clinical significance of TdRPase in IDCs and benign diseases of the pancreas were assessed, especially in relation to the efficacy of chemotherapy with 5-FU or its derivatives. METHOD: The expression of TdRPase in 148 specimens of pancreatic IDCs (66 primary lesions, 46 nodal lesions and 36 distant metastases from 126 patients) and in 24 specimens of benign diseases (4 cystadenomas, 3 hyperplasias, and 17 chronic pancreatitises) was examined by immunohistochemical staining with anti-TdRPase monoclonal antibody and evaluated in terms of three grades of immunoreactivity: negative 0, low 1, or high 2. RESULTS: Positive TdRPase staining (low and high immunoreactivity) was detected in 71% (47/66) of the primary lesions, in 46% (21/46) of the involved nodes, in 53% (19/36) of various lesions of distant metastasis, and in 37% (9/24) of the benign diseases. The staining intensity was significantly higher in the IDC tissues than in the benign disease tissues, and significantly lower in the metastatic lesions than in the primary lesions. TdRPase reactivity did not correlate with the survival rate in both resectable and unresectable IDCs. In patients with both primary tumor and nodal involvement, however, high TdRPase activity in involved nodes was significantly associated with a poor prognosis. On the other hand, although adjuvant chemotherapy was found to improve the survival of patients, TdRPase activity in the tumor did not show any significant relationship with the efficacy of chemotherapy with 5-FU or its derivatives. CONCLUSIONS: The present study suggested that in pancreatic IDC the activity of TdRPase in primary lesions is different from that in metastatic lesions, and that DNA is synthesized mainly through the salvage pathway in primary lesions and through a de novo pathway in metastatic lesions. This may be one of the reasons for the heterogeneity in chemosensitivity of human pancreatic IDC.

Plant polysaccharide PSK: cytostatic effects on growth and invasion; modulating effect on the expression of HLA and adhesion molecules on human gastric and colonic tumor cell surface.

PSK is a plant polysaccharide widely used for cancer immunotherapy in Japan and other Asian countries. It is considered that its antitumor effect is derived from its immunomodulating activity on the tumor-bearing host. The present study was designed to assess the direct action of PSK on in vitro proliferation and invasion of human KATO-3 gastric and Colo205 colonic cancer cell lines, and the expression of surface molecules such as HLA and adhesion molecules on these cells. The in vitro growth of KATO-3 cells was significantly inhibited by 100 micrograms/ml of PSK 48 hrs after culture initiation, and that of Colo205 was significantly inhibited by 10 and 100 micrograms/ml of PSK 24 hrs after culture initiation. The effect of PSK on the in vitro invasion of the tumor cells, assessed with a Matrigel invasion chamber, revealed that invasion of KATO-3 and Colo205 cells was inhibited by more than 10 micrograms/ml and more than 5 micrograms/ml of PSK, respectively. KATO-3 cells expressed HLA-ABC, HLA-A2/A28, HLA-DR very weakly, at almost baseline levels, but HLA-B27, B2-microglobulin and HLA-DQ were expressed at various levels. After treatment of KATO-3 cells with PSK, the expression of HLA-B27 and beta 2-microglobulin was significantly enhanced. Colo205 cells expressed all class-I antigens tested in this study at different levels, but class-II antigens at almost baseline levels. PSK also enhanced the expression of class-I antigens on Colo205 cells. ICAM-1 was expressed on KATO-3, but not on Colo205. The expression of ICAM-1 was enhanced to a greater extent by treatment with 10 micrograms/ml than with 100 micrograms/ml of PSK. Adenocarcinoma antigen AC-81 was strongly expressed on both cell lines, but PSK-treatment significantly enhanced its expression. These results suggested that enhancement of HLA class-I expression on tumor cells after PSK treatment may be one of the mechanisms responsible for the induction of anti-tumor immunity by PSK.

Correlation between TGF-beta1 and p21 (WAF1/CIP1) expression and prognosis in resectable invasive ductal carcinoma of the pancreas.

Transforming growth factor-beta1 (TGF-beta1) inhibits the growth of a variety of epithelial cells; however, in many types of tumors it loses its inhibitory effect. p21(WAF1/CIP1), one of the cyclin-dependent kinase (Cdk) inhibitors induced by TGF-beta1, is considered a downstream effector of the growth-inhibitory function of TGF-beta1. We assessed the clinicopathologic significance of TGF-beta1 and p21 expression in resectable invasive ductal carcinoma (IDC) of the pancreas. Immunohistochemical examination of the expression of TGF-beta1 and p21 in 62 patients revealed positive expression of TGF-beta1 in 28 (45%) and of p21 in 25 (40%) of the 62 patients, and a significant correlation between the two expressions. The survival curve of patients with TGF-beta1(+) tumors was significantly higher than that of patients with TGF-beta1(-) tumors; p21(+) patients showed a higher survival curve than did p21(-) patients, but the difference was not statistically significant. Simultaneous analysis of TGF-beta1 and p21 expression showed that the patients with TGF-beta1(+)/p21(+) tumors had a significantly better prognosis than the others. Multivariate analysis showed that TGF-beta1 was a significantly low risk factor for death due to IDC. The concurrent evaluation of TGF-beta1 and p21 expression would be an effective tool in the prediction of the prognosis of patients with pancreatic cancer.

Apoptosis and expression of Bcl-2 and Bax proteins in invasive ductal carcinoma of the pancreas.

The Bcl-2 family of genes plays important roles in the regulation of apoptosis. The present study was designed to assess the clinicopathologic significance of apoptosis and the expression of the apoptosis-inhibitory Bcl-2 protein (pBcl-2) and the apoptosis-promoting Bax protein (pBax) in human invasive ductal carcinomas (IDCs) of the pancreas. The present study included 66 IDCs that were resected between 1982 and 1998. Apoptosis was assessed by the in situ nick end labeling method and pBcl-2 and pBax were stained immunohistochemically. Apoptosis was quantified as the apoptotic index (AI, the percentage of apoptotic cells of the total tumor cells), and a high AI (>10%) was observed in 26 of the 66 (39%) IDCs. The AI correlated significantly with the extent of nodal involvement. pBax immunoreactivity was detected in 42 of 66 IDCs (64%), and pBax expression was significantly correlated with female gender and showed a significant negative correlation with the extent of nodal involvement. pBcl-2 was expressed in 16 IDCs (24%) but did not show any correlation with the clinicopathologic factors. The AI did not correlate with the expression of pBcl-2 or pBax, but there was a significant correlation between the expression of pBcl-2 and that of pBax; 15 of the 16 pBcl-2(+)IDCs were also pBax(+), and only one pBcl-2(+)IDC was pBax(-). Univariate analysis demonstrated that the degree of apoptosis had no significant influence on the patients' prognosis, pBax or pBcl-2 expression was significantly associated with a better prognosis, and in particular, the pBax(+)pBcl-2(+) group had a significantly higher survival than the other groups. On the other hand, the survival curve of the adjuvant chemotherapy (ACT) group was also higher than that of the surgery alone (SA) group, with borderline statistical signfiicance. The ACT group showed a significantly better survival rate than the SA group for the pBax(+)IDC patients, but the AI and pBcl-2 expression were not correlated with an improved survival rate in the ACT group. Multivariate analysis showed that the AI. pBcl-2 expression, and pBax expression by themselves did not represent significant variables for death owing to IDC, but pBax expression was significantly associated with the efficacy of ACT. In conclusion, pBax expression may be essential for pBcl-2 expression. pBcl-2 and pBax expressions are not significant prognostic factors for patients with IDC, but pBax expression may be beneficial in predicting the effects of ACT on patients with IDC.

Expression of Bcl-2 and p53 protein in resectable invasive ductal carcinoma of the pancreas: effects on clinical outcome and efficacy of adjuvant chemotherapy.

BACKGROUND AND OBJECTIVES: p53 tumor suppressor gene has a dual role as a trigger of apoptosis and as an initiator of DNA repair. The Bcl-2 can work to protect cells from apoptosis, which is induced by p53 gene. These facts suggest the significant role of these genes in the genesis and progression of various tumors. The present study was designed to assess the significance of p53 and Bcl-2 protein (pBcl-2) expression on resectable invasive ductal carcinoma (IDC) of the pancreas. METHODS: The present study included 63 IDCs, which were resected between 1982 and 1998. pBcl-2 and p53 were stained immunohistochemically with monoclonal antibodies. RESULTS: pBcl-2 was expressed in 16 (25.4%), and p53 was positively expressed in 32 out of 63 IDCs (50.8%); however, expression of pBcl-2 did not necessarily correlate with that of p53. Although p53 expression did not show any significant influence on the patients' survival, pBcl-2(+) patients showed a higher survival than pBcl-2(-) patients for both p53(+) and p53(-) patients, which suggested that pBcl-2 expression had a more significant effect on the survival of patients than p53 expression. On the other hand, there were no differences in the survival curve between the adjuvant chemotherapy (ACT) group and the surgery alone (SA) group. pBcl-2 expression had no influence on the effect of ACT, the ACT group showed a significantly better survival than the SA group for p53(+) IDC patients. CONCLUSIONS: pBcl-2 expression is a beneficial prognostic factor for patients with IDC, whereas p53 expression may be beneficial in the prediction of the effects of adjuvant chemotherapy on patients with IDC. J. Surg. Oncol. 2001;76:188-196.

Comparison of K-ras point mutations at codon 12 and p21 expression in pancreatic cancer between Japanese and Chinese patients.

BACKGROUND AND OBJECTIVES: K-ras (Kirsten-ras) point mutation (PM) in codon 12 are suggested to be significantly associated with the tumorigenesis of pancreatic cancer. The incidences of K-ras PMs in human pancreatic cancer are reported to be different between Europeans and Japanese. The present study was designed to compare the incidences and profile of K-ras PMs and ras-p21 expression in primary invasive ductal carcinoma (IDC) of the pancreas between Japanese and Chinese. METHODS: The specimens included 51 Japanese and 34 Chinese patients with the primary IDC of the pancreas. K-ras PMs were tested by allele specific oligonucleotide dot blot hybridization methods and ras-p21 expression was stained by the immunohistochemical method. RESULTS: K-ras PMs were detected in 48 Japanese IDCs (94%) and in 24 Chinese ones (71%). There was a significant difference between the two groups. The GAT mutation was more frequent both in Japanese (61%, 33/54) and in Chinese (60%, 18/30) IDCs. The transitions/transversions ratio in the Japanese group was 2.4 in this study. By contrast, that in the Chinese group was 1.5. The expression of p21 was detected in 24 Japanese IDCs (47%) and in 24 Chinese IDCs (71%). There was a significant difference between the two groups. The expression of p21 and the patterns of K-ras PMs did not show any significant influence on the survival of the patients both in Japanese and Chinese. In the present study, Chinese IDC had a lower frequency of K-ras PMs in codon 12 than Japanese IDC. The pattern of K-ras PMs in Chinese IDC was different from that in Japanese and European IDC, respectively. CONCLUSIONS: Ki-ras PM and p21 expression were frequently seen both in Japanese and Chinese patients with pancreatic cancer. Factors such as lifestyle and environment may have influences on pancreatic carcinogenesis in various populations.

Reduced invasiveness and metastasis of Chinese hamster ovary cells transfected with human interleukin-17 gene.

Human IL-17 (hIL-17) stimulates epithelial, endothelial, fibroblastic cells and macrophages to secrete various cytokines. The present study was designed to assess the effects of the transfection of the hIL-17 gene in Chinese hamster ovary (CHO) cells. A complementary DNA (cDNA)-encoding hIL-17 was obtained by polymerase chain reaction (PCR) amplification from human CD4+ T-cell cDNA and inserted into the plasmid pRc/CMV to construct an expression vector for hIL-17. CHO cells were transduced with hIL-17 DNA-carrying cytomegalovirus (CMV)-based retroviral vectors. A clone with a high mRNA expression of hIL-17 (CHO/IL-17) was selected by Northem blotting. There was no significant difference in the in vitro growth of cells among parent CHO cells, vector-only transfected cells (CHO/neo) and CHO/IL-17 cells. A Matrigel invasion chamber assay, however, demonstrated significantly lower invasiveness by CHO/IL-17 cells than by either the parent CHO or the CHO/neo cells. There was no difference in the in vivo growth among the cells, when subcutaneously transplanted into nude mice. When injected into the tail vein, however, the number of metastatic nodules in the lungs of CHO/IL-17-injected mice was significantly smaller than that of CHO- or CHO/neo-injected mice. Furthermore, NK activity of spleen cells was significantly higher in nude mice transplanted with CHO/IL-17 cells than in mice transplanted with parent CHO or CHO/neo cells. In conclusion, the hIL-17-gene-transfected CHO cells showed a significantly lower metastatic potential to the lung by directly modulating the invasiveness and metastasis of CHO cells as well as by enhancing NK activity.

Induction of tumor-specific antitumor immunity after chemotherapy with cisplatin in mice bearing MOPC-104E plasmacytoma by modulation of MHC expression on tumor surface.

Chemotherapy sometimes results in induction of specific antitumor immunity. We investigated the mechanisms responsible for the induction of antitumor immunity in mice bearing MOPC-104E plasmacytoma after chemotherapy with cisplatin (CDDP), especially the effects of CDDP on the expression of MHC on the tumor surface. BALB/c mice were subcutaneously (s.c.) inoculated with MOPC-104E cells on day 0, then intravenously (i.v.) treated with CDDP at 3.6 mg/kg on day 7. The tumors disappeared completely on day 35 and the mice rejected a second challenge with MOPC-104E, but did not reject syngeneic Meth-A fibrosarcoma. The tumors did not regress, however, when MOPC-104E was s.c. transplanted in nude mice, or when anti-T-cell monoclonal antibodies were i.v. injected into BALB/c mice before CDDP treatment on day 6. To determine which of the mice or tumor were affected by CDDP, BALB/c mice were inoculated with CDDP-treated (12.5 micrograms/ml for 3 hours in vitro) MOPC-104E cells on day 0, 7 and 14. The potential to reject MOPC-104E was lower in mice immunized with ethanol-treated MOPC-104E cells than in those immunized with CDDP-treated cells. CDDP-treated or -untreated MOPC-104E cells ultrasonicated and fractionated into soluble and insoluble fractions by centrifuging, also induced antitumor immunity. Flow cytometry demonstrated that the expression of MHC-class-I antigens H-2Dd and H-2Kd was enhanced after CDDP-treatment, but that of class-II antigens I-Ad and I-Ed was not, suggesting that CDDP induced tumor-specific antitumor immunity by enhancing the expression of MHC-class-I antigens.

Immunohistochemical studies on vascular endothelial growth factor and platelet endothelial cell adhesion molecule-1/CD-31 in islet transplantation.

Neovascularization may be necessary for better and longer function of transplanted islets. Vascular endothelial growth factor (VEGF) is known to be one of the most important factors of angiogenesis. Recently, VEGF was reported to be expressed in islets of normal pancreas. We studied the expression of VEGF and neovascularization related peptides in transplanted islets. To determine the angiogenic microcapillary, immunochemical staining was performed for Factor VIII-related antigen (von Willebrand factor [vWF]) and platelet endothelial cell adhesion molecule-1/CD31 (PECAM-1), both of which are known as markers of the angiogenic microvessel. Transplantable islets were isolated from Lewis rats (8-10 weeks of age) by discontinuous dextran gradient after collagenase digestion. Seven to twelve hundred islets were injected into the portal vein (IPV group, n = 7) or transplanted into subnephrocapsular cavity (SNC, n = 12) of the same descent rats. In the IPV group, the liver was resected 1 hour, 1 week, or 4 weeks after transplantation (Tx). In the SNC group, the kidney was resected 1, 3, 7, or 28 days after Tx. Each tissue was fixed in formaldehyde and embedded in paraffin. Serial 4-microm slices were immunostained for insulin, VEGF, PECAM-1, or vWF using specific antibodies. In IPV group, insulin-positive cells were VEGF positive as were in the normal pancreas at all time points. Islets of 1 hour after Tx were barely PECAM-1 positive as were in normal pancreas, but islets became weakly stained at 7 and 28 days after Tx. In vWF staining, transplanted islets showed stronger staining than those in the normal pancreas. In SNC group, VEGF was also stained in insulin-positive cells at 1, 3, 7, and 28 days. In PECAM-1 staining, islets of 1 day after Tx were barely stained as were in normal pancreas. However, the staining was increasingly enhanced from 3 to 7 days and then appeared weakened at 28 days after Tx. In vWF staining, islets were always vWF positive, as was seen in IPV group. This study revealed that PECAM-1 appeared in islets after islet Tx, suggesting that neovascularization occurs within the islet grafts. On the other hand, VEGF of transplanted islet did not obviously vary with time. Enhancement of the neovascularization may lead to better results of islet Tx.

Age-related changes of defocus-specific contrast sensitivity in healthy subjects.

To investigate the effect of defocus on contrast sensitivity as a function of age in healthy subjects, the through focus contrast sensitivity was measured in 100 healthy subjects aged 20-69. Defocus-specific changes in contrast sensitivity reflect age-related changes in the optics of the eye. Tests were performed in cycloplegic eyes varying artificial pupil size (2, 4 and 6 mm), defocus (-1 to +2 D), and spatial frequency (1-16 cpd). Integrated contrast sensitivity was taken as a measure for the total amount of visual information transferred by the optical media. At optimal focus, integrated contrast sensitivity and log contrast sensitivity at 8 cpd showed a significant age-related decline. The log contrast sensitivity at 1 cpd appeared to be independent of age. The depth of focus for a 4-mm pupil increased significantly with age, even though contrast sensitivity at +2 D defocus decreases with age too, but not as much as the contrast sensitivity at optimal focus. Our study indicates that the effect of defocus on contrast sensitivity decreases with age; this was attributed to age-related changes in the optical media.

Intraperitoneally implanted artificial pancrease with transkaryotic beta-cells on microcarrier beads in a diffusion chamber improves hyperglycemia after 90% pancreatectomy in rats.

BACKGROUND: Considering the difficulties in pancreas transplantation, the development of an artificial pancreas would be of great value. We have established a transkaryotic artificial beta-cell line, CHO/I, produced by transfecting the human proinsulin gene into the Chinese hamster ovary (CHO) cell line. The present study was designed to assess the value of an artificial pancreas using a diffusion chamber containing CHO/I cells. MATERIALS AND METHODS: Wistar rats rendered diabetic by 90% pancreatectomy were treated by implanting a diffusion chamber containing CHO/I cells cultured on microcarrier beads. RESULTS: The diffusion chamber containing microcarrier beads produced 100-folds more CHO/I cells than the chamber alone, as calculated from the secreted IRI in vitro. When diffusion chambers containing CHO/I cells on microcarrier beads were implanted into the peritoneal cavity of the 90% pancreatectomized rats, the fasting serum IRI level increased and the fasting blood glucose decreased to the normal level for 12 weeks. An intraperitoneal glucose tolerance test demonstrated, however, that the diffusion-chamber-implanted rats did not respond to glucose loading. CONCLUSION: An artificial pancreas using a diffusion chamber containing human proinsulin gene transfected cells might be a promising model for future clinical application.