Allelotype and replication error phenotype of small cell lung carcinoma

Allelotype and replication error (RER) phenotype analyses were performed to clarify the pathogenetic significance of inactivation of tumor suppressor genes and genomic instability in the genesis and progression of small cell lung carcinoma (SCLC). We examined 37 cases of SCLC for loss of heterozygosity (LOH) and microsatellite instability at 49 loci on all 39 nonacrocentric chromosomal arms. LOH was frequently (>70%) detected on chromosomes 3p (29/32, 90.6%), 5q (15/21, 71.4%), 13q (25/26, 96.2%), 17p (22/25, 88.0%), and 22q (24/33, 72.7%). Frequent LOH (>70%) on these loci was observed even among seven cases of stage I tumors. The incidence of LOH on all 39 nonacrocentric chromosomal arms was not significantly different between primary tumors and metastases. These results suggest that inactivation of multiple tumor suppressor genes accumulates relatively early during progression of SCLC and it may be responsible for clinically and biologically aggressive phenotype of SCLC. RER was observed in 6/37 (16.2%) of SCLC, however, RER at multiple loci was observed only in two cases. Therefore, it was indicated that genomic instability is uncommon, but might play a role in the genesis of a small subset of SCLC.

[Salivary gland masses: dynamic MR imaging and pathologic correlation]

PURPOSE

To evaluate the efficiency of dynamic contrast-enhanced magnetic resonance imaging (MRI) for the diagnosis of salivary gland masses.

MATERIALS AND METHODS

We retrospectively examined 19 salivary gland masses that were pathologically diagnosed by surgical operation or biopsy. We obtained T1- and T2-weighted images on MRI, performed dynamic studies on each mass and examined the correlation between enhancement patterns and pathological findings.

RESULTS

Four enhancement patterns were recognized on contrast-enhanced MRI: type 1 showed marked, homogeneous enhancement; type 2 slight, homogeneous enhancement; type 3 marginal enhancement; and type 4 poor enhancement of the mass. Most pleomorphic adenomas had a type 1 enhancement pattern, but two had a type 2 pattern. Pathologically, each mass enhancement pattern had different tumor cell and matrix components. Warthin's tumor generally showed the type 4 pattern. Primary malignant tumors of the salivary gland all showed the type 3 pattern, and pathological specimens showed many tumor cells along the marginal portion of the tumor. One inflammatory cyst and one Warthin's tumor also showed the type 3 pattern. Except for metastatic renal cell carcinoma, the enhancement patterns of late phase images and dynamic study images were the same.

CONCLUSIONS

Dynamic MRI added little diagnostic information about salivary gland masses, but the contrast-enhanced MR features correlated well with the pathological findings.

Inhibition of the binding of SNAP-23 to syntaxin 4 by Munc18c

SNARE proteins have been implicated in the insulin-induced translocation of vesicles containing the GLUT4 glucose transporter to the plasma membrane of adipocytes. The role of the target SNARE SNAP-25 or its homologs in this process was investigated by screening a mouse adipocyte cDNA library with rat SNAP-25 and human SNAP-23 cDNA probes. Both positive clones isolated encoded a protein with 87% sequence identity to human SNAP-23, and which was therefore designated mouse SNAP-23. Immunoblot and immunofluorescence analyses revealed that SNAP-23 is located predominantly in the plasma membrane of 3T3-L1 adipocytes incubated in the absence or presence of insulin. Of syntaxins 1 to 5, SNAP-23 bound with the highest affinity to syntaxins 1 and 4 in the yeast two-hybrid system. Expression of SNAP-23, syntaxin 4, and the syntaxin-binding protein Munc 18c in COS cells revealed that Munc18c reduced the amount of SNAP-23 bound to syntaxin 4 in a concentration-dependent manner. These results suggest that the binding of SNAP-23 to syntaxin 4 is inhibited by Munc18c in adipocytes.

Topographic anatomy of paraclinoid carotid artery aneurysms: usefulness of MR angiographic source images

We evaluated the usefulness of magnetic resonance angiography (MRA) for showing the topography of paraclinoid carotid artery aneurysms in 27 patients with 30 paraclinoid aneurysms undergoing conventional angiography, three-dimensional time-of-flight MRA and surgery. The anatomy shown on the axial MRA source images was consistent with that found at surgery. The neck of the aneurysm could always be identified on the source images, while it could not be analysed exactly on conventional angiography in 3 cases (10%). The optic nerves, including those displaced by the aneurysm, were recognised in all patients. The anterior clinoid process was shown as a low-intensity rim or area contiguous with the cortical bone. The source images were of great value in understanding the topography of paraclinoid carotid artery aneurysms.

Quantitative analysis of NM23 protein immunoreactivity in renal cell carcinoma using an image analyzer

PURPOSE

nm23 is a candidate tumor suppressor gene. Whether or not tumor metastasis suppressive activity is present in renal cell carcinoma (RCC) was studied.

MATERIALS AND METHODS

Immunohistochemical analysis of nm23 protein using an anti-human nm23 H1/H2 polyclonal antibody was performed in 67 RCCs and in the corresponding 67 normal proximal renal tubules (NTs). The quantity and intensity of nm23 protein immunoreactivity were evaluated using a computer-interfaced image analyzer, and the obtained results were compared with pathological findings and clinical outcome.

RESULTS

The quantity and intensity of nm23 protein immunoreactivity were significantly higher in RCCs than those observed in NTs (p <0.0001, respectively). Both quantity and intensity of nm23 protein immunoreactivity held a tendency to increase along with histological grade (p = 0.094 and p = 0.089, respectively) and T category (p = 0.063 and p = 0.063, respectively). Similarly, the immunoreactivity had a tendency to be higher in RCCs with lymph node involvement than those tumors without involvement (p = 0.060 and p = 0.067, respectively). However, no significant difference in nm23 protein immunoreactivity was found between tumors with and without distant metastasis. Using a univariate analysis, a high nm23 protein immunoreactivity (quantity > or = 51.0% or intensity > or = 72.5%) significantly correlated with a poor clinical outcome (p = 0.0051 and p = 0.0013, respectively). Furthermore, a multivariate analysis adjusted to age, T, N and M categories, showed that a high intensity of nm23 protein immunoreactivity was significantly associated with a poor clinical outcome in patients with RCCs (p = 0.0192).

CONCLUSIONS

Immunohistochemical analysis of nm23 protein intensity is an additional tool for analyzing the difference of biological features in RCCs. The potential role of the tumor metastasis suppressive activity of nm23 remains unclear in RCCs.

Epstein-Barr virus BHRF1 protein protects intestine 407 epithelial cells from apoptosis induced by tumor necrosis factor alpha and anti-Fas antibody

Tumor necrosis factor (TNF) and cytotoxic T lymphocytes, which utilize Fas to induce apoptosis in target cells, are known to play a critical role in the host defense against viral infection. In this study, the Epstein-Barr virus BHRF1 protein was stably expressed in intestine 407 cells which were susceptible to cell death mediated through both the TNF receptor and Fas. WST-1 conversion assays and acridine orange staining showed that vector-transfected control cells were killed by TNF-alpha or anti-Fas antibody in a dose-dependent manner, whereas BHRF1-expressing cells were resistant to apoptosis induced by these mediators. DNA fragmentation, a characteristic of apoptosis induced by TNF-alpha and the anti-Fas antibody, was suppressed in BHRF1-expressing cells. These results indicate that the BHRF1 protein protects cells from apoptosis mediated by the TNF receptor and Fas. The role of BHRF1 as an inhibitor of cytokine-induced apoptosis during the Epstein-Barr virus lytic cycle in vivo is discussed.

Expression of Epstein-Barr virus latent membrane protein 1 protects Jurkat T cells from apoptosis induced by serum deprivation

It has been generally accepted that inhibition of apoptosis is important in the development of malignancy. To determine whether Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1), the virus-coded transforming oncogene product, has an anti-apoptotic function in non-B-cells, Jurkat T cells were transfected with the LMP1-expression vector pSV2gptMTLM consisting of the human metallothionein promoter and were selected for mycophonolic acid resistance. LMP1-expressing clones of Jurkat cells showed resistance to apoptosis induced by serum deprivation. In LMP1-expressing clones, although the levels of Bcl-2 and Bax were similar to those in the clones of vector transfectants or parental cells, c-Myc expression was significantly depressed. Down-regulation of c-Myc by LMP1 was confirmed by using LMP1-expressing clones treated with CdCl2. Addition of c-myc antisense oligonucleotides to Jurkat cells specifically inhibited apoptosis induced by serum deprivation at the concentrations which suppressed c-Myc expression. These results suggest that LMP1 expression and subsequent down-regulation of c-Myc protect Jurkat T cells from apoptosis induced by serum deprivation. The significance of the anti-apoptotic function of LMP1 in non-B, Jurkat T cells is discussed in relation to the pathogenesis of EBV malignancy.

[Surgical management of extracranial internal carotid artery aneurysms]

Aneurysms of the extracranial internal carotid artery are rare but may present as a mass, with ischemic symptoms, or with fatal hemorrhage. We operated on aneurysms in four patients, two males and two females, whose ages ranged from 47 to 57 years. While a lot of etiological factors for the aneurysms have been known to include trauma, vascular dysplasia, infection or surgery using patch graft for carotid endarterectomy, three aneurysms in our series were atherosclerotic and one was spontaneously dissecting. One patient had focal neurological deficit due to embolism, two presented with a growing cervical mass, and one was symptom-free. The aneurysm was located proximal below the angle of the mandible in three patients and was distal above the angle in one. All patients were found able to tolerate test occlusion of the internal carotid before surgery. The aneurysm was trapped in one case (case 1) and was encased by vascular prosthesis in another (case 4). In the other two cases, arterial reconstruction after aneurysmal resection was carried out. In one case out of the two, the aneurysm was located at the level of 2nd cervical vertebral body (case 2). Vertical mandibular osteotomy was performed posteriorly to the exit of the inferior alveolar nerve from the bone, which gave a good view of the upper third of the internal carotid artery and facilitated primary end-to-end anastomosis. In the other case in which there was a dilated distal carotid artery and multiple aneurysms at the basilar and bilateral vertebral arteries (case 3), an extracranial-intracranial (EC-IC) saphenous vein bypass was inserted so as not to increase the hemodynamic stress in the posterior circulation. Except for a transient lower cranial nerve palsy in one case (case 2), there were no incidences of morbidity or death. Magnetic resonance angiography (MRA), Doppler ultrasonography or three-dimensional CT angiography (3-D-CT-A) was found useful in evaluating the change of aneurysmal size. It is essential in surgery for an internal carotid artery aneurysm to choose an appropriate approach characterized by its size and location. It may be important in cases with associated vascular lesions to estimate the potential hemodynamic change that might be induced by aneurysmal surgery.

[Regulation of apoptosis by the latent infection membrane protein 1 of Epstein-Barr virus]

The latent infection membrane protein 1(LMP1) of Epstein-Barr virus(EBV) protects human B cells from apoptosis by up-regulating expression of Bcl-2 and A20. We have demonstrated that LMP1 transfectants of Jurkat T cells are resistant to apoptosis induced by serum depletion without affecting Bcl-2/Bax system. Expression of LMP1 in epithelial cells have affected apoptosis induced by TNF-alpha but not apoptosis induced by anti-Fas antibodies, suggesting that LMP1 is involved in the signal pathway specific for TNF receptor. These results indicate that LMP1 regulates apoptosis by different mechanisms among each cell type. The regulation of apoptosis by LMP1 is discussed in relation to EBV infection.

Evidence for facilitation of motor evoked potentials (MEPs) induced by motor imagery

This study examined the extent to which motor imagery can facilitate to specific pools of motoneurons. Motor commands induced by motor imagery were subthreshold for muscle activity and were presumably not associated with any change in background afferent activity. To estimate excitability changes of flexor carpi radialis (FCR) muscle motoneuron in spinal and cortical level, electric stimuli for recording H-reflex and transcranial magnetic stimulation (TMS) for recording motor evoked potentials (MEPs) were used. During motor imagery of wrist flexion, remarkable increases in the amplitude of the MEP of FCR were observed with no change in the H-reflex. Furthermore, facilitation of antagonist (extensor carpi radialis; ECR) was also observed. Therefore, it is concluded that internal motor command can activate precisely cortical excitability with no change in spinal level without recourse to afferent feedback.

Clinical significance of immunohistochemically detectable p53 protein in renal cell carcinoma

OBJECTIVE

To elucidate the clinical significance of p53 protein in renal cell carcinoma (RCC).

MATERIALS AND METHODS

The p53 protein in the paraffin-embedded materials taken from 72 patients with RCCs was evaluated immunohistochemically and was compared with the histological findings, expression of proliferating cell nuclear antigen (PCNA), genetic instability as assessed by 2c deviation index (2cDI) and 5c exceeding rate (5cER) as well as clinical outcome.

RESULTS

The p53 positivity was demonstrated only in a localized and/or focal area of the cancerous tissue. The positive rate of p53 protein was 40.3% in this study. The p53 protein significantly correlated with nuclear grade as well as PCNA expression (p < 0.001 and p < 0.01, respectively). Although there was a wide scatter of 2cDI and 5cER values between p53 positive and negative RCCs, the RCC with positive p53 exhibited significantly higher values in 2cDI as well as 5cER, as compared to that with negative p53 (p < 0.02 and p < 0.005, respectively). However, some of the RCCs with negative p53 showed relatively higher values in 2cDI and 5cER. Using univariate analysis, the prognostic relevance was noted in T, N, M categories, age and p53 positivity, while it was not in 2cDI, 5cER and PCNA expression. Multivariate analysis demonstrated that N category and p53 positivity were independently significant indicators in predicting survival.

CONCLUSIONS

The presence of p53 protein might reflect the genetic instability already occurred. The p53 positivity reflecting a high cellular proliferation could afford an additional but useful information when predicting survival in patients with RCC.

Hemodynamics in an arterial union--simulation study on therapeutic unilateral vertebral artery occlusion

Hemodynamic changes following unilateral vertebral artery (VA) occlusion were investigated in a rat model. The left carotid artery was resected and anastomosed to the right side in an end-to-side fashion to create a half-ring bypass. The distal side of the bypass was regarded as a union of VAs. Changes in the geometry, histology and hemodynamics in the union were investigated after the recipient artery was ligated. Intimal thickening was most prominently observed in the recipient arterial segment distal to the ligation site, where the lumen was obliterated. However, the portion of the lumen within 2.6 +/- 0.6 (mean +/- s.d.) mm, a distance of 2.9 +/- 0.6 times the internal diameter from the union, was not obliterated. The angle of the union was positively related to the length of this residual lumen. The results of this study explain some of the pathogenesis in unsuccessful aneurysmal thrombosis or brain stem infarction after therapeutic unilateral VA occlusion.

Immunohistochemical analysis of proliferating cell nuclear antigen, p53 protein and nm23 protein, and nuclear DNA content in transitional cell carcinoma of the bladder

BACKGROUND

Transitional cell carcinoma (TCC) of the bladder displays an unpredictable biologic behavior and the morphologic methods of grading tumor malignancy are often insufficient to predict the clinical outcome of patients with TCC of the bladder. Thus, the new indicator should reliably reflect prognosis. In this study, the authors determined the prognostic significance of proliferating cell nuclear antigen (PCNA), p53 protein, and nm23 protein, as well as nuclear DNA content in specimens with TCC of the bladder.

METHODS

Paraffin embedded materials taken from 77 patients with nonmetastatic untreated TCC of the bladder (classified as pTa-3b, NO, MO) treated with total cystectomy were employed in this study. PCNA expression, p53 protein and nm23 protein immunoreactivities, and the parameters for nuclear DNA content such as 2c deviation index (2cDI) and 5c exceeding rate (5cER) were evaluated using a computer-assisted image analyzer, and the results were compared with histologic findings and clinical outcome.

RESULTS

PCNA expression positively correlated with p53 protein and nm23 protein immunoreactivities, 2cDI value, and 5cER. In addition, histologic grade positively correlated with all of these five parameters. Similarly, pT category and disease progression positively correlated with all of the five parameters, except for nm23 protein immunoreactivity. In tumors with high genetic instability as judged by 2cDI and 5cER, both PCNA expression and p53 protein immunoreactivity were elevated, whereas nm23 protein immunoreactivity was not. However, the percent coefficient of variation in PCNA expression was smaller than that observed in p53 protein immunoreactivity in each group of genetic instabilities. In univariate analysis, prognostic potential was found with histologic grade, pT category, PCNA expression, p53 protein immunoreactivity, 2cDI value, and 5cER, but was not noted in nm23 protein immunoreactivity. Multivariate analysis indicated that quantity and intensity of PCNA expression (chi 2 = 8; P = 0.0047 for quantity and chi 2 = 8.71; P = 0.0032 for intensity) and 2cDI value (chi 2 = 5.52; P = 0.0019) were independent variables of histologic grade and pT category when predicting survival. However, p53 protein and nm23 protein immunoreactivities and 5cER were not of independent significance.

CONCLUSIONS

The tumor growth fraction as assessed by PCNA immunostaining is an independently significant predictor for survival of patients with TCC of the bladder.

[Hemodynamic simulation study of cerebral arteriovenous malformations: changes of wall stress and early detection of NPPB]

Obliteration procedures for large high-flow arteriovenous malformations (AVM) were simulated using a compartmental flow model to investigate the role of altered autoregulatory conditions in the development of hyperperfusion and normal perfusion pressure breakthrough (NPPB). Since the arterioles are primarily responsible for autoregulatory function, the role of these structural changes on the development of hyperperfusion was also studied by evaluating the wall thickness (T), internal radius (Ri) and tangential wall stress (sigma). As the AVM flow was decreased during the obliteration procedures, the perfusion pressure (delta P) of the brain tissue surrounding the AVM increased. When the autoregulatory condition was impaired [AR (-)] and the lower limit of the autoregulatory pressure range (LAR) was shifted from 60 mmHg (LAR60) to 40 mm Hg (LAR40), the flow volume in the surrounding brain (Fb) increased markedly, from 67 ml/100g/min to 92 ml/100g/min, with the progress of the obliteration procedures. In these conditions, T/Ri was supposed to be constant and sigma value increased uniformly. In the presence of the autoregulatory mechanism [AR (+)], T/Ri increased against increasing delta P, which resulted in smaller sigma value than that under AR (-) conditions. When the contracted vascular wall yielded on the process of increasing wall stress, delta P and feeder pressure (Pf) decreased to some degree. Concomitantly increase of the sigma value and marked hyperperfusion developed in the brain. The yield of the contracted vascular wall would result in the decrease of a pressure gradient across the arteriole and the reciprocal increase of pressure load on the walls of the capillary and venula, which might lead to NPPB. Since the decrease of delta P or Pf during the progress of the obliterating procedures is considered specific to the appearance of hyperperfusion or NPPB, monitoring these parameters would be useful for its early detection. If the upper limit of the autoregulatory pressure range was assumed to decrease and become the yield point in the brain surrounding high flow AVMs, hyperfusion or NPPB could be considered to develop in the conditions with the autoregulatory pressure range being narrowed and/or shifted to the lower pressure level. Induced systemic hypotension was found to be effective in reducing the magnitude of Fb, delta P, and Pf when induction was appropriately performed in stepwise fashion. T/Ri and sigma were kept in narrow ranges compared to those before induction of hypotension.

[Anti-apoptotic function of the Epstein-Barr virus LMP1 and BHRF1 proteins]

Two Epstein-Barr virus (EBV) gene products, latent infection membrane protein 1 (LMP1), expressed mainly in latent infection, and BHRF1, expressed in lytic infection, have the ability to promote cell survival. LMP1 protects human B cells from apoptosis by upregulating expression of Bcl-2 and A20. We have demonstrated that LMP1 transfectants of Jurkat T cells are resistant to apoptosis induced by serum depletion without affecting the Bcl-2/Bax system. Overexpression of LMP1 in epithelial cells inhibits apoptosis induced by TNF-alpha, but not by anti-Fas antibodies. These results indicate that the anti-apoptotic mechanism of LMP1 differs among different cell types. BHRF1 can prevent apoptosis induced by TNF-alpha and anti-Fas antibodies in epithelial cells. The implication of the anti-apoptotic function of LMP1 and BHRF1 is reviewed in relation to EBV infection.

Intravesical instillation of epirubicin: effect on tumour recurrence in patients with dysplastic epithelium after transurethral resection of superficial bladder tumour

OBJECTIVE

To evaluate whether the intravesical instillation of epirubicin is effective in preventing the recurrence of tumour in the bladder where dysplastic mucosa remains after transurethral resection of tumour.

PATIENTS AND METHODS

Biopsy specimens were taken from apparently normal areas of the bladder mucosa in patients undergoing transurethral resection of the primary tumours. Of the 75 evaluable patients, 18 (24%) had abnormalities in at least one or more specimens. The patients were divided into two groups, 57 with normal and 18 with abnormal biopsy results. Intravesical chemotherapy with epirubicin (20 mg/40 mL saline) was randomized to patients in each group. Tumour recurrence rates were estimated and compared amongst the groups. Factors related to tumour recurrence were evaluated using univariate and multivariate analyses.

RESULTS

The risks of tumour recurrence and progression were evaluated in 18 patients with concomitant mucosal abnormalities. All 10 patients with abnormal biopsy results who were treated with epirubicin had recurrence of tumour within a mean interval of 9 months, whereas six of eight controls had recurrence within a mean of 10.9 months. While there was progression in grade in four of 10 patients with abnormal biopsy results and treated with epirubicin, none of the recurrent tumours in six control patients with mucosal abnormalities progressed in grade. The overall recurrence-free rate of the patients with mucosal abnormalities was higher in controls than in those receiving epirubicin, but the difference was not statistically significant. There were no significant differences in recurrence rate for those treated with epirubicin and controls in the 57 patients with normal biopsy results. Univariate analysis showed that the recurrence-free rates were significantly influenced by tumour multiplicity and the mucosal biopsy results (P < 0.001 and P = 0.02, respectively). In a Cox proportional-hazards model, tumour multiplicity alone had prognostic significance for tumour recurrence (P = 0.002).

CONCLUSIONS

The prophylactic intravesical instillation of epirubicin had no effect in preventing tumour recurrence and, conversely, it may promote tumour progression in bladders with dysplastic mucosal changes.

Contralateral external carotid-to-external carotid artery (half-collar) saphenous vein graft for common carotid artery occlusion

In a patient having common carotid artery occlusion complicated with contralateral internal carotid artery stenosis, a saphenous vein bypass graft was performed from the contralateral external carotid artery to the ipsilateral external carotid artery simultaneously with contralateral carotid endarterectomy. The bypass was patent 1 year later and the patient was free from fainting spells. Among a number of the reconstructive surgical procedures, this "half-collar bypass" can be placed adequately in the subcutaneous soft tissue so that head or mandibular movement does not displace or compress the graft. Intraoperative hemodynamic measurements were considered useful in determining surgical options.

Hemodynamic simulation study of cerebral arteriovenous malformations. Part 2. Effects of impaired autoregulation and induced hypotension

The hemodynamic changes occurring during obliteration procedures for arteriovenous malformations (AVM) have not been fully elucidated. Therefore, we undertook a simulation study using a compartmental flow model to investigate the role of altered autoregulatory conditions in the development of hyperperfusion during obliteration of large high-flow AVM. Induced hypotension was also simulated to evaluate its usefulness in reducing the incidence and severity of the event. As the AVM flow was decreased during the obliteration procedures, feeder pressure increased and drainer pressure decreased, with a concomitant increase in the perfusion pressure in the brain tissue surrounding the AVM. Cerebral blood flow (CBF) remained constant at 50 ml 100 g-1 min-1 in the presence of autoregulation and increased to 67 ml 100 g-1 min-1 in its absence. When the lower limit of the autoregulatory pressure range (LAR) was shifted from 60 to 50 or 40 mm Hg, the flow volume increased markedly from 67 to 77 ml 100 g-1 min-1 or to 92 ml 100 g-1 min-1 after complete obliteration. Decrease in LAR would be a cause of the hyperperfusion. Induced systemic hypotension was found to be effective in reducing the magnitude of these hemodynamic changes, when induction was appropriately performed in a stepwise fashion. A simulation study is useful in clarifying the various hemodynamic changes that develop during the treatment of AVM.

A large thrombosed superior cerebellar artery aneurysm: a case report

MATERIAL AND RESULT: A large thrombosed aneurysm arising from the distal superior cerebellar artery was successfully resected.

DISCUSSION AND CONCLUSION

An aneurysm in this location is very rare. Accumulation of intraoperative hemodynamic data may be useful in evaluating the capacity of collateral circulation.

Factors related to the outcome of M-VAC in 101 patients with advanced urothelial cancer

The objective of this study is to identify factors related to the results of intravenous methotrexate, vinblastine, doxorubicin and cisplatin (M-VAC) for 101 patients with advanced urothelial cancer. The effects of various factors on response and survival were evaluated using univariate and multivariate analyses. The factors included in the analyses were sex, age, performance status (PS), primary site, histological type, grade, T category, N category, M category, prior chemotherapy, prior radiotherapy, and dose of chemotherapeutic drugs. Univariate analysis revealed that M category and prior chemotherapy had a significant correlation with the response, and that factors significantly related to survival were PS, primary site, N category, M category, prior chemotherapy and prior radiotherapy. A multiple logistic regression model showed that N category, M category and prior chemotherapy were related to response. The response rates of patients with N1-4 or M1 or prior chemotherapy were lower than those with N0 or M0 or without prior chemotherapy. A Cox regression model demonstrated that PS and M category independently contributed to survival. Patients with high grade PS or distant metastases showed a lower survival rate than those with low grade PS or localized diseases. M category was the most important factor related to response and survival. These results seem to indicate the low effectiveness of M-VAC for distant metastases, and the inability of this regimen to improve the outcome of patients with advanced urothelial cancer.

Molecular analysis of mutations induced by 2-chloroacetaldehyde, the ultimate carcinogenic form of vinyl chloride, in human cells using shuttle vectors

Vinyl chloride (VC) is a carcinogen associated with human and animal cancers. The ultimate carcinogenic form of VC, 2-chloroacetaldehyde (CAA), has been suspected to be mutagenic and we confirmed the mutagenicity of CAA using a modified shuttle vector plasmid. Base sequence analyses of 109 mutant plasmids with mutations in the supF gene, which were treated with CAA and propagated in the cultured human cells, revealed that more than half of the single base substitutions were G:C to A:T transitions with eight hotspots. The majority of the mutations involving G:C base pairs were in 5'-AAGG-3' or 5'-CCTT-3' sequences suggesting that these sequences are the main targets of mutagenesis caused by CAA.

[Two cases of acute massive pulmonary embolism diagnosed by pulmonary angiography with Swan-Ganz catheter]

We report two cases of acute massive pulmonary embolism diagnosed at the bedside by pulmonary angiography with Swan-Ganz catheter. In both cases the patients (women 48 and 49 years old) went into shock after surgery. Pulmonary angiography with Swan-Ganz catheter was done at the bedside to confirm the diagnosis. In both cases this revealed filling defects. Hemodynamics improved after-thrombolytic therapy. In general, pulmonary embolism can be definitively diagnosed by lung perfusion scan or pulmonary angiography. Pulmonary angiography with a Swan-Ganz catheter is useful in hospitals without complicated instruments, but is indicated only for unmovable and unstable patients with hemodynamic problems.