DT-diaphorase as a determinant of sensitivity to adriamycin in non-small-cell lung-cancer cell lines

We have reported the establishment of a mitomycin-C (MMC)-resistant non-small-cell lung-cancer cell line, PC-9/MC4. As determined by an MTT assay, this resistant cell line was found to be 4 times more sensitive to adriamycin (ADM) than was the parental PC-9. There were no significant differences in sensitivity to etoposide, mitoxantrone, daunomycin, epirubicin, pirarubicin, 9-aminoanthracycline or 3'-deamino-3'-morpholino-13-deoxo-10-hydroxy carminomycin. These data suggest that neither qualitative or quantitative changes in DNA topoisomerase II nor the enhanced repair of DNA can explain the differing sensitivity to ADM observed. No significant differences were found in the accumulation of ADM and glutathione (GSH) in these cell lines. Although total glutathione-S-transferase (GST) activity in PC-9/MC4 cells was lower than that observed in PC-9 cells and treatment with ethacrynic acid (EA) reduced sensitivity to ADM in both cell lines, relative resistance was unaffected. NADH-cytochrome b5 reductase (B5R) activity in PC-9/MC4 cells showed a 3-fold greater decrease than that in PC-9 cells, and DT-diaphorase (DTD) activity in PC-9/MC4 cells showed an approximately 200-fold greater decrease than that in PC-9 cells. Addition of dicumarol, an inhibitor of DTD, decreased the sensitivity of ADM of PC-9 but not of PC-9/MC4. DTD activity in the PC-9 cell line was inhibited by treatment with dicumarol while in PC-9/MC4 it remained unchanged. These data suggest that DT-diaphorase is a determinant of sensitivity to ADM in the 2 cell lines.

[Chyluria treated with inguinal lymphangiovenous and lymph node-venous anastomosis: a case report]

Stripping and ligation of the renal lymphatics has been a standard operation for patients with chyluria in Japan. However, recently, inguinal lymph node-saphenous vein anastomosis and lymphangiovenous anastomosis in the spermatic cord or the lower limb are introduced as a microsurgical treatment of chyluria with good result from China. We present a case of 50-year-old female with chyluria, which was cured by the lymphatic-venous anastomosis at the groin. The patient had lived in Okinawa, an area of endemic filariasis, till 23 years of age. She noted chyluria for the first time at 28 years of age, when it was treated by irrigation of the renal pelvis with silver nitrate solution. The symptom recurred at 48 years of age, and fatigue developed two months before admission. The conservative treatments including rest, low fat diet and repeated irrigation of the renal pelvis were carried out, but these were ineffective. Therefore, bilateral inguinal lymph node-saphenous vein anastomosis and lymphangiovenous anastomosis in the same wound on the right were performed. The chyluria disappeared five months after the operation. The lymphatic-venous anastomosis at the superficial part of the body may be the surgical procedure of choice, because they are effective, simple, less invasive and less traumatic.

[Persistent müllerian duct syndrome: report of two cases]

Persistent Mullerian duct syndrome is characterized by the retention of mullerian derivatives in patients otherwise normally virilized. Clinically, the persistence of uterus and tubes leads either to cryptorchidism or inguinal hernia. The condition is usually discovered at surgery. We report two boys with this anomaly. In each case, hysterectomy and orchidopexy were carried out. The gonads were testes and the karyotype was 46, XY. Long-term follow up for these patients is necessary because of an increased risk of testicular tumors and infertility which will develop in future.

Microinjections of angiotensin II into the supraoptic and paraventricular nuclei produce potent antidiureses by vasopressin release mediated through adrenergic and angiotensin receptors

We investigated the effects of angiotensin II (Ang II), microinjected into the supraoptic (SON) and paraventricular (PVN) nuclei of rats, on the urine outflow rate and underlying mechanisms. Ang II produced antidiuretic effects in a dose-dependent manner with ED50 values of 0.1 and 0.05 nmol in the SON and PVN, respectively. [Sar1, Ile8]Ang II at 0.1 nmol diminished the Ang II (0.5 nmol)-induced antidiureses in the SON more markedly than in the PVN. A high dose of [Sar1,Ile8]Ang II, 1 nmol, completely inhibited the effects in both the nuclei. In addition, the Ang II (1 nmol)-induced antidiuretic effects were partially inhibited by phenoxybenzamine (80 nmol) in the SON and by phenoxybenzamine, timolol (100 nmol) and propranolol (100 nmol) in the PVN. The microinjection of Ang II (1 nmol) into both the nuclei, after pretreatment with a vasopressin V1V2-antagonist, d(CH2)5-D-Tyr(Et)VAVP (i.v.) significantly increased the urine outflow rate. These findings suggest that 1) Two mechanisms account for the Ang II receptor-mediated antidiureses resulting from an increase in vasopressin release: direct stimulation on vasopressin-containing neurons and indirect stimulation on them through alpha-adrenoceptors in the SON and alpha- and beta-adrenoceptors in the PVN; 2) The Ang II-induced antidiuretic effect in the SON is slightly less potent than that in the PVN; and 3) Ang II receptors in the nuclei may possibly produce the diureses through mechanisms that are not presently understood.

[A case of prostatic adenocarcinoma with pulmonary metastases--diagnosis by transbronchial lung biopsy and immunohistochemistry]

Metastatic pulmonary adenocarcinoma was found in a 79-year-old man, who had symptoms of general malaise and poor appetite. An extensive work-up including a transurethral resection of the prostate, failed to establish the primary site of the malignancy. By administering chlormadinone acetate for prostatic hypertrophy, the pulmonary metastases improved dramatically. The tumor cells in the lung, which had previously been obtained by transbronchial lung biopsy, stained positive for prostatic acid phosphatase and prostatic specific antigen. These data suggested that prostatic carcinoma had metastasized to the lung. The prostatic carcinoma was finally confirmed at autopsy.

Study of the balance between coagulation and fibrinolysis in disseminated intravascular coagulation using molecular markers

Plasma levels of thrombin-antithrombin III complex (TAT), plasmin-alpha 2-plasmin inhibitor complex (PIC) and active plasminogen activator inhibitor (PAI) were assayed in 66 cases of disseminated intravascular coagulation (DIC). Significant elevation of both TAT and PIC was observed in all cases of DIC. Most elevated levels of TAT were seen in DIC with acute promyelocytic leukaemia (APL) and sepsis. The highest levels of PIC were seen in DIC with APL but were much lower in sepsis. A significant elevation in active PAI was observed in DIC due to acute leukaemia (apart from APL), chronic myeloid leukaemia and sepsis, but not in APL, non-Hodgkin lymphoma and cancer. Active PAI was higher in patients with multiple organ failure (MOF) than in those without MOF while PIC was lower in patients with this complication. Thus, the balance of coagulation and fibrinolysis varied according to the underlying cause of DIC; APL had more dominant activation of fibrinolysis, while sepsis had greater activation of coagulation. It is suggested that the inhibition of secondary fibrinolytic activation plays an important role in the progression of MOF by the disturbance of the microcirculation.

Vasodilating actions of cromakalim in resting and contracting states of carotid arteries from spontaneously hypertensive rats

To determine the properties of cromakalim-opened K+ channels in arterial smooth muscle of spontaneously hypertensive rats (SHR), the effects of cromakalim on tension and 86Rb efflux were compared in endothelium-denuded strips of carotid arteries from 13-week-old SHR and normotensive Wistar-Kyoto rats (WKY). The addition of cromakalim or of nifedipine to resting strips caused a relaxation only in SHR. When strips from both strains were contracted with 15.9 mM K+, the magnitude of the precontraction was greater in SHR than in WKY. Under these conditions, relaxant responses to lower concentrations of cromakalim were decreased and those to higher concentrations of cromakalim were increased in SHR. When strips from both strains were contracted with a different concentration of K+ to an equivalent magnitude (78% of the maximum) relaxant responses to cromakalim were greater in SHR than in WKY. When strips were contracted with 10(-7) M norepinephrine, the precontraction was similar between SHR and WKY, and relaxant responses to cromakalim were greater in SHR. In both strains, the relaxant responses to cromakalim were competitively antagonized by glibenclamide, a blocker of ATP-sensitive K+ (KATP) channels, with a pA2 value of approximately 7.3. Charybdotoxin (10(-7) M), a blocker of Ca(2+)-activated K+ (KCa) channels, did not inhibit the relaxant responses to cromakalim in both strains. Charybdotoxin alone elicited a contraction, which was greater in SHR than in WKY. In resting strips preloaded with 86Rb, the basal 86Rb efflux rate constant was higher in SHR than in WKY. The addition of cromakalim (10(-5) M) to the resting strips increased the 86Rb efflux rate constant in both strains to a similar peak value. The addition of nifedipine (10(-7) M) to the resting strips decreased the basal 86Rb efflux rate constant only in SHR, and concomitantly affected the action of cromakalim in SHR. The results suggest that (1) cromakalim caused arterial relaxation via the opening of KATP channels in both SHR and WKY, (2) although the relaxant effects of cromakalim tended to be greater in SHR than in WKY, the differences were rather small, depended on the precontraction tone and varied with the concentration of the vasoconstrictors, and (3) there was an increased basal Ca2+ influx and a high activation of KCa channels in the resting state of SHR arteries, and these changes might influence the effects of cromakalim.

Endothelium-derived relaxing factor released by 5-HT: distinct from nitric oxide in basilar arteries of normotensive and hypertensive rats

1. The role of the endothelium in cerebrovascular responses to 5-hydroxytryptamine (5-HT) was investigated in spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto rats (WKY) in vitro. 2. Cumulative addition of 5-HT caused concentration-dependent contractions in ring preparations of SHR basilar arteries; the contractile response was smaller in WKY basilar arteries. 3. Removal of the endothelium enhanced markedly the contractile responses to 5-HT in WKY arteries but had only a slight effect in SHR arteries. The responsiveness to 5-HT in WKY arteries after removal of endothelium was comparable to that in SHR arteries. 4. The endothelium-dependent relaxation induced by acetylcholine in WKY basilar arteries was almost abolished by treatment with 10 microM methylene blue or 10 microM NG-nitro-L-arginine (L-NOARG). However, the response to 5-HT was not affected by treatment with methylene blue, L-NOARG or indomethacin. 5. Application of 10-20 mM K+ or 3.2 mM tetraethylammonium (TEA) did not change significantly, or only increased slightly, the resting tension, but markedly enhanced the contractile response to 5-HT in WKY arteries with endothelium. In contrast, the submaximal response to 5-HT in SHR arteries with endothelium was significantly enhanced by 0.3 mM TEA. 6. In the presence of 1 mM TEA, the application of 10 microM L-NOARG further enhanced the responses of 5-HT in WKY arteries with endothelium. In SHR arteries with endothelium, 10 microM L-NOARG per se enhanced slightly but significantly the responses to 5-HT. 7. These results indicate that 5-HT-induced contraction in basilar arteries is substantially attenuated by an endothelium-dependent mechanism in WKY, but to a much lesser extent in SHR. The major relaxing factor released by 5-HT from endothelium in WKY is distinct from NO and may exert its effect by activating K+ channels.

Effects of aerosol administration of a thromboxane receptor antagonist (S-1452) on experimental asthma in guinea pigs

The importance of thromboxane A2 (TXA2), one of the arachidonate metabolites, in the pathogenesis of bronchial asthma has been emphasized recently. Because aerosolized administration of antiasthmatic drugs is effective and safe, this study examined the effect of aerosolized TXA2 receptor antagonist (S-1452) on allergic bronchoconstriction in passively sensitized and mechanically ventilated guinea pigs. Under the cover of antihistamine, antigen-induced bronchoconstriction was markedly inhibited by pretreatment with aerosolized S-1452 inhalation in a dose-dependent manner. Although aerosolized S-1452 itself provoked weak bronchoconstriction for its partial agonist effect, bronchial responsiveness to inhaled histamine did not change 10 min after S-1452 inhalation. These results indicate that aerosolized S-1452 may be useful in treating bronchial asthma.

[Prune belly syndrome with atresia ani and urethral stricture: a case report]

A case of prune belly syndrome associated with urethral stricture and atresia ani is reported. Cystostomy and colostomy were performed on his birthday. Cutaneous vesicostomy, bilateral ureterocystoneoplasty and proctoplasty were performed when the patient was one year old, and urethrotomy was performed when he was four years old. He was closely followed for six years and six months, and had developed without any serious episodes. We collected 128 cases of prune belly syndrome from the Japanese literature including this, and made a brief discussion of this syndrome with urethral stricture and atresia ani.

Effects of DX-9065a, an orally active, newly synthesized and specific inhibitor of factor Xa, against experimental disseminated intravascular coagulation in rats

We investigated the protective effects of DX-9065a, an orally active, newly synthesized and specific inhibitor of factor Xa, against two kinds of experimental disseminated intravascular coagulation (DIC) in rats. Endotoxin-induced experimental DIC was induced by a 4-h sustained infusion of endotoxin at a dose of 100 mg/kg. Thromboplastin-induced experimental DIC was induced by a bolus injection of thromboplastin at a dose of 150 mg/kg. The rats were orally administered DX-9065a at 10, 30 or 100 mg/kg 30 min before endotoxin or thromboplastin injection. In both DIC models, DX-9065a showed a protective effect against DIC, at all doses and in all parameters, including fibrin/fibrinogen degradation products (FDP), fibrinogen level, prothrombin time, activated partial thromboplastin time, platelet count and the number of renal glomeruli with fibrin thrombi. When DX-9065a was orally administrated at 100 mg/kg without endotoxin or thromboplastin, no significant changes were seen in hemostatic parameters except PT and APTT, and no fibrin thrombi or abnormal bleeding were seen in renal specimens. These findings suggest that the new oral anti-Xa drug, DX-9065a, has an effect in reducing the severity of DIC. However, further dose-finding and safety studies of this drug have still to be assessed.

Functional role of charybdotoxin-sensitive K+ channels in the resting state of dog basilar artery

To determine the possible role of Ca(2+)-activated K+ (KCa) channels in the regulation of resting tone of cerebral arteries, the effect of agents which interact with these channels on tension and 86Rb efflux was examined in endothelium-denuded strips of dog basilar artery, and data were compared with findings in the mesenteric artery. The basilar artery maintained a myogenic tone; that is, the resting tone decreased when nifedipine was added. The addition of charybdotoxin, a blocker of large conductance KCa channels, caused a concentration-dependent contraction in the basilar artery but not in the mesenteric artery. In strips preloaded with 86Rb, the basal 86Rb efflux rate constant was significantly greater in the basilar artery than in the mesenteric artery. Nifedipine decreased the basal 86Rb efflux rate constant only in the basilar artery. The basal 45Ca influx in the resting state of the basilar artery was significantly increased when compared with the mesenteric artery and this increase in the basilar artery was reduced by nifedipine. The results suggest that the charybdotoxin-sensitive KCa channels regulate the myogenic tone in the resting state of the basilar artery. The activation of KCa channels in the basilar artery appears to be secondary to the increased transmembrane Ca2+ influx probably via the activation of L-type voltage-dependent Ca2+ channels in the resting state of this artery.

[Argyrophilic proteins of nucleolar organizer regions of macrophages and lymphocytes in bronchoalveolar lavage fluid from patients with diffuse lung diseases]

Alveolar macrophages and T-lymphocytes in bronchoalveolar lavage fluid from patients with diffuse lung diseases have been shown to be activated. The object of this study was to investigate whether the numbers of nucleolar organizer regions (NORs) in alveolar macrophages and lymphocytes were abnormally high in these patients or not. Alveolar macrophages and lymphocytes were collected by bronchoalveolar lavage from 7 control subjects, 36 patients with pulmonary sarcoidosis, 10 patients with hypersensitivity pneumonitis, 6 patients with measles pneumonia, 6 patients with mycoplasma pneumonia, and 6 patients with progressive systemic sclerosis related to interstitial pneumonitis. These cells were cytocentrifuged and stained by one-step silver staining. Argyrophilic proteins of the nucleolar organizer regions (Ag-NORs) were counted in 300 alveolar macrophages and lymphocytes. The numbers found in control subjects were compared to those found in patients with diffuse lung diseases. In the patients with sarcoidosis, these numbers were also compared among subgroups divided according to staging, involvement of other organs, administration of steroids, and differences in deposition of 67Ga. We also examined correlations between Ag--NORs and known markers of activation in sarcoidosis. The numbers of Ag-NORs were significantly greater in patients with diffuse lung diseases than in control subjects. There were no significant differences in the numbers of Ag-NORs among subgroups of patients with sarcoidosis. No correlations were seen between the Ag-NORs and the markers of activation of disease.(ABSTRACT TRUNCATED AT 250 WORDS)

[Development of new drugs for intractable vasculitis--lipo-PGE1 and monoclonal antibody]

"Lipo-PGE1", PGE1 incorporated into lipid microspheres (LM), has marked antiplatelet and vasodilatory actions. Since LM largely accumulate in inflamed vascular lesions, lipo-PGE1 shows a marked efficacy for treating vascular diseases such as atherosclerosis and vasculitis. Another recently developed drugs against intractable vasculitis are monoclonal antibodies to surface antigens of lymphocytes. Treatment with humanized anti-CDw52, and subsequent anti-CD4 monoclonal antibodies was reported to have brought remission up to 42 months.

[A case of liver cirrhosis presenting with right pleural fluid without ascites]

A 80-year-old man was admitted to our hospital complaining of appetite loss, dry cough, and dyspnea on exertion. Chest X-ray film showed massive right pleural effusion. On physical examination, the right thorax was dull to percussion, and breath sounds of the right lung field were diminished. Examination of the cardiovascular system was unremarkable. Hepatosplenomegaly and ascites were not evident. The character of the pleural fluid was transudative. Cytological findings were negative and culture of the pleural fluid was normal. First, the pleural fluid was diminished by thoracic drainage. But, after the cessation of drainage, the pleural fluid soon reaccumulated. Abdominal ultrasonography showed typical liver cirrhosis pattern without ascites. An intraperitoneal injection of 99mTc-sulfur colloid was followed by positive uptake of radioactivity in the right pleural cavity from 1 hour after the injection, demonstrating the existence of a direct perito-pleural communication. Thus, the diagnosis of liver cirrhosis presenting with right pleural fluid, without ascites was made. This case indicates that the absence of ascites cannot exclude cirrhosis as the etiologic cause of pleural effusion.

Latex agglutination test negative cryptococcal meningitis in an immuno-competent individual: a case report

We report a case with progressive mental deterioration and persistent low grade fever, who was diagnosed to have cryptococcal meningitis. This case is unique in that the cryptococcal latex agglutination antigen test was consecutively negative. The diagnosis was made by sequential CSF culture.

The role of basement membrane in colorectal cancer invasion and liver metastasis

BACKGROUND

Basement membrane (BM) is a specialized extracellular matrix component that plays a key role in tumor invasion and metastasis.

METHODS

Immunohistochemical staining for two major components of BM, type IV collagen (C IV), and laminin (LN), utilizing avidin-biotin-peroxidase complex detection to examine 182 primary colorectal cancers (pT2 or greater) and 20 liver metastases.

RESULTS

The distribution of C IV was the same as of LN in colorectal cancer tissue, and in normal tissue. Both C IV and LN staining were more frequently positive in the superficial zone but infrequently in the deep zone of the primary tumor. BM preservation, C IV and LN staining in both the superficial and deep zones, was seen in 18.7% of the subjects. The rate of BM preservation significantly decreased with increasing histologic grade (P < 0.01). No correlation was observed between pT number and BM preservation. The rate of BM preservation in cases of liver metastasis was 84.4%, significantly higher than the rate in cases without liver metastasis (P < 0.001). BM was observed even at the advancing front of tumor invasion and was preserved in 95.0% of the liver metastases.

CONCLUSIONS

BM is a functional substance that appears to accompany cancer rather than function as a structural barrier against cancer invasion and liver metastasis.

Establishment of the ELISA for murine soluble gp130, a signal transducer for the IL-6 family cytokine, and its detection in the ascitic fluids of tumor-bearing mice

Interleukin-6 (IL-6) signal is transduced through a membrane glycoprotein gp130, which associates with the IL-6 receptor alpha chain (IL-6R alpha) in the presence of IL-6. We prepared monoclonal antibodies (mAbs) specific to murine gp130 by immunizing rats and hamsters with a chimeric molecule consisting of the extracellular domain of murine gp130 and human immunoglobulin (Ig) G1 Fc (m130Ig). Furthermore, we developed a sandwich ELISA for detection of murine soluble gp130 (sgp130) and showed that sgp130 was present in the ascitic fluids of tumor-bearing mice. Because sgp130 can inhibit the biological activities of the IL-6-related cytokine subfamily that can enhance anti-tumor immune response and also has both growth inducing and growth inhibitory activities on various tumors, the results suggest that sgp130 in tumor-bearing host modulates tumor progression.

Immunologically cross-reactive 57 kDa and 53 kDa glycoprotein antigens of bovine milk fat globule membrane: isoforms with different N-linked sugar chains and differential glycosylation at early stages of lactation

Two glycoprotein antigens with molecular masses of 57 kDa (MGP57) and 53 kDa (MGP53) were co-purified from bovine milk fat globule membrane (MFGM) by immunoaffinity chromatography using a monoclonal antibody raised against the MFGM. Their N-terminal sequences of 22 amino acids determined were identical, and the sequence was homologous (about 60% identical) to the deduced amino acid sequence of mouse milk fat globule epidermal growth factor (EGF) factor 8 (MFG-E8) (Ref. [12], Stubbs, J.D. et al., Proc. Natl. Acad. Sci. USA, 87, 8417-8421, 1990). This suggests that MGP57/53 are bovine MFGM components 15/16 (PAS-6 and PAS-7), which have recently been reported to be bovine homologs of MFG-E8. N-Glycanase treatment of these glycoproteins reduced their molecular masses, and consequently the enzymatically deglycosylated MGP57 and MGP53 converged on a single band of 50 kDa as measured by SDS-PAGE, indicating that the polypeptide portions of these two distinct glycoprotein antigens are very similar or identical and that their N-linked sugar chains contributed to minor difference in their molecular masses. Western blot analyses using lectins also revealed that they were differentially glycosylated; MGP57 was stained with concanavalin A (Con A) more strongly than MGP53, whereas MGP 53 was stained well with soybean agglutinin (SBA). Reactivity with SBA remarkably increased during early stages of lactation. Two-dimensional gel electrophoresis showed that MGP57 and MGP53 were electrically heterogeneous; from day 9 after parturition, both glycoproteins fell in almost the same range of isoelectric points between 6.4 and 7.6, also, such glycoproteins from day 1 after parturition were more acidic, probably due to terminal sialylation of their sugar chains.

Rhabdomyolysis associated with bacteremic pneumonia due to Staphylococcus aureus

A case of rhabdomyolysis associated with bacteremic pneumonia due to Staphylococcus aureus is reported. A 58-year-old man was admitted because of severe left lobar pneumonia, and presented myoglobinuria on admission. The serum creatine phosphokinase level was transiently elevated and myoglobinuria were disclosed. Sputum and venous blood cultures grew Staphylococcus aureus. Rhabdomyolysis has rarely been reported in cases of bacterial infection, especially those due to Staphylococcus aureus. This case might be an extremely rare case of rhabdomyolysis complicating Staphylococcus aureus bacteremia following severe left upper lobar pneumonia.

A total delivery system of genetically engineered drugs or cells for diseased vessels. Concept, materials, and fabricated prototype device

The development of a percutaneous procedure using a catheterized system for diseased vessels has been increasingly in demand in conjunction with gene therapy using genetically engineered drugs (antisense) and cells. The authors' strategic concept realizes revascularization at narrowed, diseased sites and delivery of drugs or cells into the diseased tissues or targeted cells. An inflatable, drug-releasing double balloon is installed at the tip of a catheter. The outer balloon, fabricated with micropores (diameters of 20 and 30 mm) by an excimer laser ablation technique, releases a viscous solution containing a photoreactive polymer and drug or cells on inflation of the inner balloon. A photoresponsive water-soluble polymer, molecularly designed for its ability to achieve prolonged local residency of antisense DNA at the tissue level and enhanced transmembrane transport at the cellular level, is premixed with antisense oligonucleotide drug. On light irradiation, the nonionic polymer is reversibly converted to a positively charged polymer that can be complexed with highly negatively charged antisense DNA (c-myb), which may enhance the transmembrane delivery of antisense. On cessation of irradiation, the complex slowly dissociates to function intracellularly as an antisense drug, resulting in inhibition of cell proliferation. Thus, our integrated, dual-function balloon system may contribute to mechanical dilatation gene therapies at diseased vessels.

Microporous polymer surfaces prepared by an excimer laser ablation technique

This paper presents an excimer laser microprocessing method to prepare microporous polymer surfaces. The irradiation of a KrF excimer laser (248 nm) was applied to several polymer films by passing a laser pulse through an optical microscope, resulting in ablative photodecomposition. The control unit was designed to control the fluence of the laser, pulse number, size of irradiated areas, and irradiation micropositioning. The ablation depth linearly increased with an increase in the accumulation of pulses. The chemical composition of the ablated surfaces did not vary with the accumulation of pulses, confirmed by x-ray photoelectron spectroscopy measurements. Excellent structuring quality of ablated micropores was obtained for polyurethane, polyimide, and polycarbonate films. As an application of the ablation technique, polyurethane films were micropored by the excimer laser ablation technique in conjunction with open-cell structured, small diameter grafts under development. In vitro cell ingrowth and compliance on the micropored polyurethane films were examined. Rapid ingrowth was observed on pore sizes of a few microns to several tenths of a micron in diameter. Higher density micropores provided enhanced elastomeric properties.