Prognostic value of vascular endothelial growth factor expression in gastric carcinoma

BACKGROUND

Many studies have shown that angiogenesis plays an important role in the growth, progression, and metastasis of solid tumors. Recently, several angiogenic factors have been identified. Vascular endothelial growth factor (VEGF) is thought to be one such angiogenic factor and is also thought to be a selective mitogen for endothelial cells. We investigated the correlation between the expression of VEGF and the progression of gastric carcinoma.

METHODS

One hundred twenty-nine specimens resected from patients with gastric carcinoma were investigated by staining with a polyclonal antibody against VEGF. Correlations between the expression of VEGF, microvessel density, and various clincopathologic factors were studied.

RESULTS

Microvessel density, determined by immunostaining for Factor VIII related antigen, was significantly higher in VEGF-positive tumors than in VEGF-negative tumors. VEGF positivity was correlated with vessel involvement, lymph node metastasis, and liver metastasis. Moreover, patients with VEGF-positive tumors had a significantly poorer prognosis than those with VEGF-negative tumors. Multivariate analysis indicated that the expression of VEGF is an independent prognostic factor in patients with gastric cancer. According to the mode of recurrence, the frequency of hepatic metastases was significantly increased among patients with VEGF-positive tumors.

CONCLUSIONS

The expression of VEGF may be a good prognostic indicator for patients with gastric carcinoma and may also be useful as a predictor of the mode of recurrence in patients with gastric carcinoma.

Prognostic value of vascular endothelial growth factor expression in gastric carcinoma

BACKGROUND

Many studies have shown that angiogenesis plays an important role in the growth, progression, and metastasis of solid tumors. Recently, several angiogenic factors have been identified. Vascular endothelial growth factor (VEGF) is thought to be one such angiogenic factor and is also thought to be a selective mitogen for endothelial cells. We investigated the correlation between the expression of VEGF and the progression of gastric carcinoma.

METHODS

One hundred twenty-nine specimens resected from patients with gastric carcinoma were investigated by staining with a polyclonal antibody against VEGF. Correlations between the expression of VEGF, microvessel density, and various clincopathologic factors were studied.

RESULTS

Microvessel density, determined by immunostaining for Factor VIII related antigen, was significantly higher in VEGF-positive tumors than in VEGF-negative tumors. VEGF positivity was correlated with vessel involvement, lymph node metastasis, and liver metastasis. Moreover, patients with VEGF-positive tumors had a significantly poorer prognosis than those with VEGF-negative tumors. Multivariate analysis indicated that the expression of VEGF is an independent prognostic factor in patients with gastric cancer. According to the mode of recurrence, the frequency of hepatic metastases was significantly increased among patients with VEGF-positive tumors.

CONCLUSIONS

The expression of VEGF may be a good prognostic indicator for patients with gastric carcinoma and may also be useful as a predictor of the mode of recurrence in patients with gastric carcinoma.

Prognostic value of vascular endothelial growth factor expression in gastric carcinoma

BACKGROUND

Many studies have shown that angiogenesis plays an important role in the growth, progression, and metastasis of solid tumors. Recently, several angiogenic factors have been identified. Vascular endothelial growth factor (VEGF) is thought to be one such angiogenic factor and is also thought to be a selective mitogen for endothelial cells. We investigated the correlation between the expression of VEGF and the progression of gastric carcinoma.

METHODS

One hundred twenty-nine specimens resected from patients with gastric carcinoma were investigated by staining with a polyclonal antibody against VEGF. Correlations between the expression of VEGF, microvessel density, and various clincopathologic factors were studied.

RESULTS

Microvessel density, determined by immunostaining for Factor VIII related antigen, was significantly higher in VEGF-positive tumors than in VEGF-negative tumors. VEGF positivity was correlated with vessel involvement, lymph node metastasis, and liver metastasis. Moreover, patients with VEGF-positive tumors had a significantly poorer prognosis than those with VEGF-negative tumors. Multivariate analysis indicated that the expression of VEGF is an independent prognostic factor in patients with gastric cancer. According to the mode of recurrence, the frequency of hepatic metastases was significantly increased among patients with VEGF-positive tumors.

CONCLUSIONS

The expression of VEGF may be a good prognostic indicator for patients with gastric carcinoma and may also be useful as a predictor of the mode of recurrence in patients with gastric carcinoma.

Requirement of multiple DNA-protein interactions for inducible expression of RNR3 gene in Saccharomyces cerevisiae in response to DNA damage

The RNR3 gene encodes the large subunit of ribonucleotide reductase. Transcription of this gene is induced 12-fold in response to DNA damage or by a DNA replication blocker. To investigate cis-acting regulation, deletion analysis of the promoter region of the RNR3 gene was performed and we identified two upstream-repressing sequences in the RNR3 regulatory region. An 18-base-pairs fragment, termed DNA-damage responsive element 1 (DRE1) located between -212 and -194 in this region was found to be essential for the induction of RNR3. This fragment contained a negatively acting sequence where a protein factor bound to the region during normal growth but disappeared by exposure to 4-nitroquinoline-1-oxide. The other repressive element homologue to DRE1 was located at -263 to -254. One possible upstream-activating sequence which regulates the basal expression of RNR3 was also found. These results show that at least three potential cis-elements are necessary for the inducible expression of yeast expression of yeast RNR3 in response to DNA damage.

Pulmonary arterial lesions in Takayasu arteritis: relationship of inflammatory activity to scintigraphic findings and sequential changes

In order to investigate the relationship between inflammatory activity and pulmonary arterial changes in Takayasu arteritis and the progression of the disease, we retrospectively reviewed 110 perfusion lung scans obtained by using 99mTc-macroaggregated albumin in a total of 57 patients. The scintigraphic findings were compared with the inflammatory activity and clinical course. Inflammatory activity was determined on the basis of the physical findings and laboratory data, i.e., the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) value. Scintigraphic abnormality was seen in 32 (56%) of the patients. The incidence of scintigraphic abnormality in the patients with active inflammation (7 of 21 patients, 33%) was lower than that in the patients in the chronic stage (22 of 32, 69%) (p < 0.02). Six of 22 patients who had undergone more than one scintigraphic examination showed progression in the scintigraphic findings. Four of the 6 patients showed relapse clinically, and corticosteroid medication could not be withdrawn from them. The lower incidence of scintigraphic abnormality in the patients with active inflammation suggests that in the acute phase no stenotic or occlusive changes in the pulmonary artery have yet been produced. Pulmonary arterial lesions can progress. The incidence of progression may be slightly higher in the patients who have had a relapse after corticosteroid therapy than in those who remained in remission after therapy or who were in the chronic stage, although neither difference was significant.

Patients with renal cysts associated with renal cell carcinoma and the clinical implications of cyst puncture: a study of 223 cases

OBJECTIVES

To clarify the association between renal cysts and renal cell carcinoma (RCC), we analyzed patient demographics, types of cystic disease, and modes of cyst-tumor coexistence along with the results of cyst puncture.

METHODS

A total of 507 hospitals provided information regarding clinical experiences with RCC and cyst puncture over a 2-year period.

RESULTS

Renal cysts were identified by preoperative imaging in 223 (4%) of 5721 patients with RCC. Histologic examination revealed cystic RCC in 56 patients (25%) and RCC associated with cystic diseases in 167 (75%). Cystic disease included simple cysts in 72 patients (32%), acquired cystic disease of the kidney (ACDK) in 62 (28%), multilocular renal cysts in 20 (9%), polycystic kidney in 3 (1%), and unspecified or miscellaneous in 10. Cyst puncture performed in 47 (21%) of 223 patients demonstrated bloody fluid in 20 cases and nonbloody fluid in 27. Cytologic analysis of cystic fluid obtained from 37 patients revealed a malignancy in 5 (14%), accounting for 25% of the bloody and 4.8% of nonbloody specimens. Cytology failed to detect RCC in ACDK and multilocular cysts but was positive in cases of cystic RCC and solitary cysts. Four of 5 cytology-positive cases comprised those of tumor in cyst and cyst within tumor.

CONCLUSIONS

Simple cysts and ACDK accounted for 60% of the renal cysts associated with RCC. Cystic RCC was involved in 25% of cases. Positive cytology may be expected in select cases, including those with close cyst-tumor relationships and those involving bloody cyst fluid. However, negative cytology does not exclude RCC.

[Pharmacokinetics of 99mTc-MAG3 and 131I-OIH: comparative study based on 2 compartment model analysis]

We studied 50 patients with mild to moderate renal dysfunction to compare pharmacokinetics of 99mTc-MAG3 with that of 131I-OIH. After simultaneous bolus injection of both 99mTc-MAG3 and 131I-OIH, 8-point venous blood sampling was performed from 2 to 44 min post injection. Aliquoted plasma samples were counted for radioactivity along with the injected standard to obtain % injected dose/ml plasma for each tracer. Using obtained time-concentration data, classical 2 compartment model analysis was performed for both tracers to obtain various pharmacokinetic parameters, including distribution volumes (Vds), inter-compartmental rate constants, and plasma clearance. In these parameters, Vd of central compartment, Vd at steady state, central to peripheral inter-compartmental rate constant, and plasma clearance were significantly larger for 131I-OIH. In all parameters, significant correlation was found between 99mTc-MAG3 and 131I-OIH. The best correlation was seen in plasma clearance (r = 0.891, p < 0.0001). Plasma clearance ratio (99mTc-MAG3/131I-OIH), however, showed weak but significant negative correlation with serum creatinine, although this correlation was not likely to affect the overall correlation of clearance between 131I-OIH and 99mTc-MAG3. From these results, we confirmed that 99mTc-MAG3 clearance could be used as an alternative to 131I-OIH clearance, although pharmacokinetic behavior of 99mTc-MAG3 was not exactly the same as that of 131I-OIH.

Regulation of secretion and clearance of C-type natriuretic peptide in the interaction of vascular endothelial cells and smooth muscle cells

OBJECTIVE

To clarify the significance of C-type natriuretic peptide in the interaction between endothelial cells and vascular smooth muscle cells by investigating the endothelial production of C-type natriuretic peptide and the clearance mechanism of C-type natriuretic peptide using the endothelial cells-smooth muscle cells co-culture system.

RESULTS

Secretion of C-type natriuretic peptide in the direct co-culture of endothelial cells with smooth muscle cells elicited as much as a 60-fold increase compared with endothelial cells alone. The accumulation of intracellular cyclic GMP in the co-culture was consequently increased and the elevation of cyclic GMP level in the co-culture was abolished by the anti-C-type natriuretic peptide monoclonal antibody. The elevated cyclic GMP production in the co-culture was abolished by the anti-transforming growth factor-beta neutralizing antibody. Candoxatrilat (10(-6)-10(-4) mol/l), a neutral endopeptidase inhibitor, dose-dependently increased the concentrations of C-type natriuretic peptide in the culture medium with endothelial cells alone, but not in the endothelial cells-smooth muscle cells co-culture. The transcript of neutral endopeptidase messenger RNA was detected in endothelial cells but not in smooth muscle cells by reverse transcriptase polymerase chain reaction. Treatment with C-atrial natriuretic factor4-23 (10(-9)-10(-6) mol/l), the specific ligand for the clearance receptor of the natriuretic peptides, resulted in dose-dependent augmentation of C-type natriuretic peptide concentration and concomitant intracellular cyclic GMP production in the endothelial cells-smooth muscle cells co-culture but not in endothelial cells alone.

CONCLUSION

The present study demonstrated that direct interaction between endothelial cells and smooth muscle cells augments C-type natriuretic peptide secretion from endothelial cells through transforming growth factor-beta activation, and revealed that the enzymatic degradation is responsible for the steady state level of C-type natriuretic peptide in endothelial cells alone and that the receptor-mediated clearance mainly determines the augmented level of C-type natriuretic peptide in the interaction between endothelial cells and smooth muscle cells. The results taken together raise the possibility that endothelial C-type natriuretic peptide might play a role in regulation of vascular tone and remodelling.

Giant splenic cyst with high serum concentration of CA 19-9. Failure of treatment with percutaneous transcatheter drainage and injection of tetracycline

BACKGROUND

Recently, several cases of nonparasitic true splenic cyst with high serum concentration of carbohydrate antigen (CA 19-9) have been reported.

CASE

We report a giant splenic cyst presenting with high serum concentration of CA 19-9 in a 21-year-old man without a history of previous trauma. Imaging techniques showed a huge monolocular cyst of the spleen, and laboratory data showed increased serum CA 19-9 levels (326 U/ml; normal, < 37 U/ml). Serologic test was negative for parasitic infection. These findings led us to the diagnosis of epithelial splenic cyst. Percutaneous transcatheter drainage and injection of tetracycline were performed for 2 weeks. The cyst shrank, and the serum CA 19-9 level decreased favorably. However, cystic fluid reaccumulated in a month.

CONCLUSIONS

The accumulation of cystic fluid in splenic epithelial cysts may be attributable not only to the secretion of the lining cells but also to influx from the splenic sinuses.

Ferric ammonium citrate-cellulose paste for opacification of the esophageal lumen on MRI

OBJECTIVE

A new ferric ammonium citrate-cellulose mixture for use in MRI of the esophagus was evaluated for its ability to opacify the esophageal lumen.

MATERIALS AND METHODS

Thirty-two patients with esophageal disorders and ten patients with normal esophagus undergoing MRI at 1.5 T were given approximately 100 ml of the newly developed high-viscosity esophageal contrast preparation. Moreover, six of the patients with esophageal cancer were subjected to a second examination after radiation therapy. A total of 48 MR imagings were performed.

RESULTS

Of the patients examined, successful esophageal opacification, graded as excellent, was obtained in 84.2, 78.9, and 57.9%, of the sagittal, axial, and coronal images, respectively. In cases of extrinsic disease involving the esophagus the contrast medium administration allowed the easy differentiation of the esophagus from adjacent mass lesions and proved very useful in identifying displacement and compression. In cases of esophageal carcinoma the contrast medium administration assisted in the measurement of wall thickness and length of the lesion as well as in the identification of the site of origin of the tumor.

CONCLUSION

The results indicate that this product effectively opacifies the esophageal lumen in the majority of patients. We found that it is easy to use, is well tolerated, and does not produce artifacts.

[Analysis of locally controlled esophageal carcinomas treated with radiotherapy]

Of 227 esophageal carcinomas treated with a radiation dose of 60 Gy or more, 100 patients had no tumor or ulceration (with or without stenosis) of the esophagus after irradiation. We analyzed local control factors of these 100 patients to determine the need for further treatment. The cumulative local control rate at five years was 40% in all cases, 37% in 21 cases without any stenosis of the esophagus and 40% in 79 cases with stenosis. The presence of stenosis of the esophagus after irradiation was not a critical factor in predicting final local control. Local recurrence of tumors with findings of Borrmann III or Borrmann IV by the pretreatment esophageal barium study, tumors controlled after a total dose of more than 80 Gy, tumors without low dose rate telecobalt therapy (LDRT; 1 Gy/hour, 5 to 7Gy/day, a total dose of 12 to 15 Gy) as boost therapy, and apparently controlled tumors with a stenotic ratio of 60% or more or with 5 cm or more length of stenosis of the esophagus after irradiation was significantly higher than that of the others (p < 0.05). Multivariate analysis revealed that findings of pretreatment barium study, total dose, with or without LDRT, and length of stenosis of the esophagus after irradiation were significantly important factors in local control. Members of the high risk group of apparently controlled tumors should undertake surgical treatment or further intensive chemotherapy.

Development of radioimmunoassay for human leptin

Using recombinant human leptin, we have produced an antiserum for human leptin and developed a radioimmunoassay (RIA) specific and sensitive for human leptin. We detected leptin-like immunoreactivity (-LI) in culture media of adipose tissue from subcutaneous abdominal fat in human. The plasma leptin-LI concentration in nonobese subjects (17.6 <body mass index (BMI)<23.0) was 5.6 +/- 1.3 (mean +/-SE) ng/ml, while that in obese subjects (29.0 <BMI) was 43.0 +/- 9.4 (mean +/- SE) ng/ml. In gel permeation chromatographic analyses, leptin-LI in culture media and plasma consisted of single component emerging at the elution position of recombinant human leptin. These findings indicate that leptin is secreted from the adipose tissue into the circulating blood as a large molecular form corresponding to recombinant leptin. The RIA developed in the present study will be a powerful tool to investigate the physiological and pathophysiological significance of leptin in human.

Potentiation of lethal endotoxin shock by streptococcal pyrogenic exotoxin in rabbits: possible relevance of hyperreactivity of macrophages to endotoxin

Streptococcal pyrogenic exotoxin (SPE) potentiates lethal shock induced by endotoxin. We have previously reported that macrophages derived from SPE-treated rabbits showed hyperreactivity to endotoxin, and that the effect of SPE on macrophages was mediated by a lymphokine(s). Here we show that culture supernatants of SPE-stimulated lymphocytes, when administered into rabbits three hours before or together with endotoxin, potentiate a variety of endotoxin-induced pathophysiological changes and even lethal shock. These results suggest that SPE-induced lymphokine(s) mediates the potentiating effect of SPE on the lethal endotoxin shock through enhancing endotoxin reactivity of macrophages which play the central role in mediating endotoxin toxicity.

Regulation of endothelial production of C-type natriuretic peptide in coculture with vascular smooth muscle cells. Role of the vascular natriuretic peptide system in vascular growth inhibition

Recently, we have demonstrated that C-type natriuretic peptide (CNP) is produced in vascular endothelial cells (ECs). In the present study, we investigated the interaction of ECs and vascular smooth muscle cells (SMCs) for endothelial production of CNP and its action on vascular growth, using the EC/SMC coculture system. The concentration of CNP-like immunoreactivity in the medium was increased 60-fold within 48 hours in the EC/SMC coculture with direct contact compared with that in EC alone. Northern blot analysis revealed the augmented expression of CNP mRNA in the EC/SMC coculture. The accumulation of intracellular cGMP in the coculture was concomitantly increased, and this response was blocked by anti-CNP monoclonal antibody and HS-142-1, a nonpeptide atrial natriuretic peptide receptor antagonist. The concentration of biologically active transforming growth factor-beta (TGF-beta) in the culture medium of the coculture with direct contact of ECs and SMCs was elevated to the level to stimulate endothelial production of CNP. Actually, the neutralizing antibody against TGF-beta abrogated the cGMP accumulation in the coculture. These results show that endothelial production of CNP in the EC/SMC coculture is at least in part regulated by TGF-beta. Furthermore, the conditioned medium from ECs stimulated by TGF-beta was demonstrated to have a growth-inhibitory effect on SMCs, which was abolished by anti-CNP monoclonal antibody and HS-142-1. The treatment with anti-CNP monoclonal antibody and HS-142-1 also significantly increased the cell number of the EC/SMC coculture. The present study reveals the pathophysiological significance of endothelial CNP as a paracrine/autocrine vascular regulator for vascular growth in the interaction of ECs and SMCs.

Clinical significance of LEA-1 expression in adult acute myeloid leukemia

In this study, we examined expressions of several adhesion molecules (AdMs), i.e. leukocyte function antigen-1 (LFA-1: CD11a/CD18), Hermes homing receptor (CD44) and intercellular adhesion molecule-1 (ICAM-1: CD54), on leukemia cells from 51 adult patients with newly diagnosed acute myeloid leukemias (AMLs) to elucidate clinical significance of these AdM expressions. Those expressions in lymphoid malignancies have been correlated with tumor evolutions, but CD44 was detected in all the AML cases examined and CD54 expression did not associate with their clinical characteristics or outcomes. However, we found that LFA-1 expressions significantly correlated with splenomegaly, resistance to induction chemotherapies and short survival periods in AML patients.

Mucin-hypersecreting tumors of the pancreas: assessing the grade of malignancy preoperatively

BACKGROUND

Mucin-hypersecreting tumor of the pancreas (MHST) is a unique variant of pancreatic tumor, where mucin was excreted from the patulous orifice of the enlarged ampulla of Vater and the main pancreatic duct was dilated with excessive mucin. It is difficult to differentiate preoperatively between benign and malignant variants.

PATIENTS AND METHODS

A total of 18 patients with an MHST were retrospectively reviewed to identify possible indicators of malignancy. The 18 tumors consisted of 9 benign lesions (hyperplasia or adenoma with mild to moderate atypia), 2 borderline disorders (adenoma with severe atypia), and 7 malignant diseases (unequivocal adenocarcinoma).

RESULTS

The age, sex, and site of origin demonstrated no significant difference among the three groups. One of the 9 patients with the benign lesion was diabetic, while 4 of the 7 patients with the malignant variant were diabetic (P<0.05). All 9 benign lesions were confined to the side branch, while 4 of the 7 malignant diseases were located in the main pancreatic duct (P<0.05). The mean greatest diameters of these three variants were 3.2 cm, 3.3 cm, and 6.6 cm, respectively. The mean greatest diameter of the main pancreatic duct in the 7 malignant disorders were larger than in the 9 benign conditions (9.7 versus 5.4 mm, P <0.05). The mean diameter of the mural nodules in the 7 malignant tumors were larger than in the 9 benign lesions (20.5 versus 5.1 mm, P <0.05). The serum and mucin carcinoembryonic antigen and carbohydrate antigen 19-9 levels showed no substantial difference between the benign and malignant variants.

CONCLUSIONS

The presence of diabetes, large tumors (> or = 5 cm), marked dilatation of the main pancreatic duct (> or = 10 mm), main pancreatic duct type, and large mural nodules (> or = 10 mm) is strongly suggestive of a malignant variant of the MHST.

Interleukin 8 and granulocyte elastase alpha 1 proteinase inhibitor complex in the tracheobronchial aspirate of infants with chronic lung disease following inter-uterine infection

In order to elucidate the role of interleukin 8 (IL-8) in the development of chronic lung disease (CLD) of neonates with intra-uterine infection, serial and simultaneous measurements of the concentration of IL-8 and granulocyte elastase alpha 1 proteinase inhibitor complex (E-alpha 1 PI) in the tracheobronchial aspirate of low birth weight infants were conducted. Infants with a high serum IgM level at birth, and who subsequently developed CLD, showed significantly high concentrations of IL-8 and E-alpha 1 PI in the first 48 h. It seemed that IL-8 stimulated neutrophils to release neutrophil enzymes which, in turn, caused the lung tissue injury, resulting in the development of CLD following intra-uterine infection.

Thymidine phosphorylase/platelet-derived endothelial cell growth factor expression associated with hepatic metastasis in gastric carcinoma

It is known that angiogenesis plays an important role in the growth and metastasis of solid tumours. Several angiogenic factors have been identified and platelet-derived endothelial cell growth factor (PD-ECGF) is thought to be one such factor. Recently, it was reported that thymidine phosphorylase (dThdPase) is identical to PD-ECGF. Using immunohistochemical staining with an anti-dThdPase antibody, we investigated the correlation between dThdPase expression and the microvessel density in 120 gastric carcinomas. The microvessel density, determined by immunostaining for factor VIII-related antigen, was significantly higher in dThdPase-positive tumours than in dThdPase-negative tumors. There was a significant correlation between dThdPase expression and the increment of microvessel density. Moreover, regarding distant organ metastasis, the frequency of hepatic metastasis was significantly higher (P < 0.01) in patients with dThdPase-positive tumours than in those with dThdPase-negative tumors. In summary, it was suggested that dThdPase expression is closely associated with the promotion of angiogenesis and hepatic metastasis in gastric carcinoma.

cDNA cloning and gene expression of human type Ialpha cGMP-dependent protein kinase

The type I cGMP-dependent protein kinase (cGK) is one of the major pathways for the cGMP cascade and has been demonstrated to inhibit platelet aggregation, relax smooth muscle cells, and control cardiocyte contractility. There are two subtypes of the type I cGK, cGKIalpha and cGKIbeta. The former is more sensitive to cGMP than the latter. In humans, cGKIbeta cDNA was isolated, but the full structure and tissue-specific gene expression of cGKIalpha have not been determined. The significance of cGK in human cardiovascular diseases has not been investigated at the molecular level. In the present study, we isolated the full-length human CGKIalpha cDNA (-36 to +2177; the translation start site: +1) enclosing the 671-amino acid protein. Nucleotides +267 to +2177 of the isolated cDNA were identical to the corresponding nucleotides of human cGKIbeta cDNA. Southern blot analysis suggested that human cGKIalpha and cGKIbeta are generated by alternative splicing of a single gene assigned to chromosome 10. By Northern blot analysis, we detected abundant human cGKIalpha mRNA (7.0 kb) in the aorta, heart, kidneys, and adrenals. In contrast, human cGKIbeta mRNA (7.0 kb) was detected abundantly only in the uterus. In cultured vascular smooth muscle cells, the type I cGK mRNA concentration was reduced to 10% of the basal level by 4 x 10(-10) mol/L platelet-derived growth factor. Angiotensin II (10(-8) mol/L), transforming growth factor-beta (4 x 10(-11) mol/L), and tumor necrosis factor-alpha (6 x 10(-6) mol/L) also exhibited an inhibitory effect on type I cGK gene expression. These findings suggest a pathophysiological implication of the type I cGK in cardiovascular diseases, including hypertension and atherosclerosis.

Changes in significance of axillary lymph node dissection for patients with breast cancer

Axillary lymph node dissection has been a routine part of breast cancer treatment for more than 100 years. As so few patients have been shown to have positive nodes, more consideration should be given to eliminating axillary node dissection for duct carcinoma in situ (DCIS) and T1a lesions. And for patients with T1/2N0M0 cancer of the breast, lumpectomy alone without axillary dissection followed by radiation therapy of the intact breast and regional lymph nodes should be a reasonable treatment without any arm morbidity. Between September 1989 and September 1994, we have treated 40 breast cancer patients with this method and no local recurrence nor distant metastasis has been encountered so far. Therefore, it is concluded that axillary dissection should be performed routinely only for N1b lesions and larger.

Comparison of routine and selective endoscopic retrograde cholangiography before laparoscopic cholecystectomy

To evaluate the role of endoscopic retrograde cholangiography (ERC) before laparoscopic cholecystectomy, we compared the frequency of concomitant common bile duct stones, their clinical outcome, and the frequency of bile duct injury between a group of 128 patients with routine preoperative ERC (group A) and 1010 patients with selective ERC (group B). Overall, 48 patients (4.2%) had duct stones, but the predictive signs were absent in six of them (12.5%). The stones were demonstrated by ERC and removed by sphincterotomy in all 11 patients in group A. Of 37 patients in group B, 22 were diagnosed by selective ERC and underwent endoscopic removal. Of four patients whose stones were found by operative cholangiography, one had immediate open surgery, another passed a stone spontaneously, and the other two underwent postoperative sphincterotomy, which failed in one. The stones were not recognized until pain recurred in the remaining 11 patients. Sphincterotomy was successful in nine patients but failed in the other two. Thus postoperative sphincterotomy failed in 3 of 13 patients (23%), necessitating open surgery. Forty-two patients overall (3.7%) had aberrant biliary tract anatomy, which did not lead to bile duct injury in any of the patients. Morbidity of routine ERC (3.1%) was lower than that of selective ERC (7.4%) (p < 0.05). It should be noted that a certain proportion of duct stones may be missed by selective ERC, necessitating laparotomy when sphincterotomy fails. The routine use of preoperative ERC may be justified at institutions where the expertise is available, at least until laparoscopic lithotomy becomes easy.

Prognostic value of vascular endothelial growth factor expression in gastric carcinoma

BACKGROUND

Many studies have shown that angiogenesis plays an important role in the growth, progression, and metastasis of solid tumors. Recently, several angiogenic factors have been identified. Vascular endothelial growth factor (VEGF) is thought to be one such angiogenic factor and is also thought to be a selective mitogen for endothelial cells. We investigated the correlation between the expression of VEGF and the progression of gastric carcinoma.

METHODS

One hundred twenty-nine specimens resected from patients with gastric carcinoma were investigated by staining with a polyclonal antibody against VEGF. Correlations between the expression of VEGF, microvessel density, and various clincopathologic factors were studied.

RESULTS

Microvessel density, determined by immunostaining for Factor VIII related antigen, was significantly higher in VEGF-positive tumors than in VEGF-negative tumors. VEGF positivity was correlated with vessel involvement, lymph node metastasis, and liver metastasis. Moreover, patients with VEGF-positive tumors had a significantly poorer prognosis than those with VEGF-negative tumors. Multivariate analysis indicated that the expression of VEGF is an independent prognostic factor in patients with gastric cancer. According to the mode of recurrence, the frequency of hepatic metastases was significantly increased among patients with VEGF-positive tumors.

CONCLUSIONS

The expression of VEGF may be a good prognostic indicator for patients with gastric carcinoma and may also be useful as a predictor of the mode of recurrence in patients with gastric carcinoma.

Properties of Ryr3 ryanodine receptor isoform in mammalian brain

Although the RNA for the third isoform (Ryr3) of ryanodine receptor (RyR), a Ca2+ release channel, is detected in specific regions of mammalian brain, little is known about the protein. We investigated Ryr3 in rabbit brain, using an antibody raised against the synthetic peptide corresponding to amino acid sequence 4375-4387 of rabbit Ryr3, the homologue of bullfrog beta-RyR. The antibody which reacted with bullfrog beta-RyR, but not with the other isoforms, Ryr1 or Ryr2, specifically precipitated a single polypeptide from rabbit brain microsomes having a size similar to beta-RyR. Sucrose gradient ultracentrifugation revealed that Ryr3 forms a homotetramer, as true of the other isoforms. Being consistent with the distribution of its RNA, Ryr3 was abundantly expressed in hippocampus, corpus striatum, and diencephalon. Ryr3 demonstrated Ca2+-dependent [3H]ryanodine binding, and caffeine increased its Ca2+ sensitivity. The Ca2+ sensitivity of Ryr3 was also enhanced in a medium containing 1 m NaCl, as observed with beta-RyR. [3H]Ryanodine binding gave an estimate of Ryr3 which would be only 2% or less of total RyR in rabbit brain. These results confirm the expression of functional Ryr3 in mammalian brain which is similar to nonmammalian beta-RyR.

Similar Ca2+ dependences of [3H]ryanodine binding to alpha- and beta-ryanodine receptors purified from bullfrog skeletal muscle in an isotonic medium

To understand the functions of the two ryanodine receptor isoforms (alpha- and beta-RyRs) in nonmammalian skeletal muscles, we determined [3H]ryanodine binding to these isoforms purified from bullfrog skeletal muscle. In 0.17 M-NaCl medium both isoforms demonstrated similar Ca2+ dependent ryanodine binding activities, while the Ca2+ sensitivity for activation of beta-RyR was increased in 1 M-NaCl medium. This enhancement in Ca2+ sensitivity depended on the kinds of salts used. These results imply that alpha- and beta-RyRs may have similar properties as Ca2+-induced Ca2+ release channels in bullfrog skeletal muscle.

Synthesis of the methyl alpha-glycosides of a di-, tri-, and a tetra-saccharide fragment mimicking the terminus of the O-polysaccharide of Vibrio cholerae O:1, serotype Ogawa

Methyl 4-(3-deoxy-L-glycero-tetronamido)-4,6-dideoxy-2-O-methyl-alpha-D- mannopyranoside was acetylated, and the fully protected methyl glycoside was treated with dichloromethyl methyl ether-ZnCl2 (DCMME-ZnCl2) reagent to give 3-O-acetyl-4-(2,4-di-O-acetyl-3- deoxy-L-glycero-tetronamido)-4,6-dideoxy-2-O-methyl-alpha-D-mannop yranosyl chloride (3). Condensation of 3 with methyl 3-O-acetyl-4-(2,4-di-O-acetyl-3-deoxy-L-glycero-tetronamido)-4,6- dideoxy-alpha-D-mannopyranoside (4) gave the fully acetylated disaccharide 5, which was deacetylated yielding the methyl alpha-glycoside of title disaccharide. The disaccharide glycosyl donor required for the blockwise synthesis of the title tri- and the tetra-saccharide, 3-O-acetyl-4-(2,4-di-O-acetyl-3-deoxy-L-glycero-tetronamido)-4,6-d ideoxy-2-O- methyl-alpha-D-mannopyranosyl-(1-->2)-3-O-acetyl-4- (2,4-di-O-acetyl-3-deoxy-L-glycero-tetronamido)-4,6-dideoxy-alpha- D- mannopyranosyl chloride (12), was obtained by condensation of 3 with the 1-O-acetyl analog of 4, followed by treatment of the disaccharide formed with DCMME-ZnCl2. The synthesis of the methyl alpha-glycoside of the title trisaccharide involved a condensation of 12 with 4, followed by deacetylation. Similarly, the condensation of 12 with 15, the latter being the analog of 5 having a free HO-2, followed by deacetylation, gave the methyl alpha-glycoside of the title tetrasaccharide. All glycosylation reactions were mediated by silver trifluoromethanesulfonate in the presence of 2,4,6-trimethylpyridine. 4-(3-Deoxy-L-glycero-tetronamido)-4,6-dideoxy-2-O-methyl-alpha,bet a-D- mannopyranose was prepared for the first time. It was characterized by NMR spectroscopy, and via its crystalline per-O-acetyl derivative. It is the saccharide whose alpha-form constitutes the terminal, non-reducing end-group of the O-PS of V. cholerea O:1, serotype Ogawa.