Characterization of aortic aneurysms in cardiovascular disease patients harboring Porphyromonas gingivalis.

OBJECTIVE: Porphyromonas gingivalis was recently shown to cause intimal hyperplasia in a mouse model by a novel cholesterol-independent mechanism, suggesting to be a pathogen-specific feature of cardiovascular diseases. The aim of this study was to characterize the clinical and histopathological features of aortic aneurysms in cardiovascular disease patients harboring oral P. gingivalis. SUBJECT AND METHODS: Aortic aneurysm specimens were collected from 76 Japanese patients who underwent surgery, of whom dental plaque specimens were also collected from 31 patients. Bacterial DNA was extracted from each specimen to detect P. gingivalis by polymerase chain reaction. Histopathological analyses of the aortic aneurysm specimens, including immunohistochemical staining for embryonic myosin heavy chain isoform (SMemb) and S100 calcium-binding protein A9 (S100A9), were also performed. RESULTS: The number of aneurysms occurring in the distal aorta was significantly higher in subjects positive for P. gingivalis in dental plaque compared with those who were negative. The expressions of S100A9 and SMemb were also significantly greater in the subjects positive for P. gingivalis in dental plaque. On the other hand, there were no significant differences in adipocellular accumulation between the groups. CONCLUSIONS: These results suggest that aortic aneurysms in patients harboring oral P. gingivalis have greater expression of S100A9 and proliferative smooth muscle cells, which was different from the present patients without oral P. gingivalis.

Molecular analysis of aortic intimal hyperplasia caused by Porphyromonas gingivalis infection in mice with endothelial damage.

BACKGROUND AND OBJECTIVE: Porphyromonas gingivalis infection is thought to be a significant etiological factor in the development of cardiovascular diseases. However, scant definitive evidence has been presented concerning the pathological molecular mechanisms of these disorders. In the present study, we performed a molecular analysis of the developmental mechanisms of aortic intimal hyperplasia induced by P. gingivalis. MATERIAL AND METHODS: The effects of P. gingivalis-induced bacteremia on intimal hyperplasia were evaluated using a mouse model of aortic hyperplasia created by photochemical-induced endothelial cell injury. Alterations of gene expression profiles in injured blood vessels of the mice were extensively analyzed using DNA microarray assays to identify the key molecules involved in P. gingivalis-induced hyperplasia. In addition, human aneurismal specimens from patients with or without P. gingivalis infection were analyzed histochemically. RESULTS: Intravenous administration of P. gingivalis dramatically induced intimal hyperplasia in the mouse model. Concomitantly, S100 calcium-binding protein A9 (S100A9) and embryonic isoform of myosin heavy chain (SMemb), a proliferative phenotypic marker of smooth muscle cells, were significantly overexpressed on the surfaces of smooth muscle cells present in the injured blood vessels. Similarly, increased expressions of S100A9 and SMemb proteins were observed in aneurismal specimens obtained from P. gingivalis-infected patients. CONCLUSION: We found that bacteremia induced by P. gingivalis leads to intimal hyperplasia associated with overexpressions of S100A9 and SMemb. Our results strongly suggest that oral-hematogenous spreading of P. gingivalis is a causative event in the development of aortic hyperplasia in periodontitis patients.

Thromboxane A(2) synthase inhibitor enhanced antithrombotic efficacy of GPIIb-IIIa receptor antagonist without increasing bleeding.

The advantage of platelet integrin GPIIb-IIIa receptor antagonists in the prevention of thrombotic occlusion was clearly proven in patients who underwent interventional treatment of the coronary artery, but its value in cerebral ischemia is still under investigation. The expectation of intracranial hemorrhage on strong inhibition of platelet function restricts its application in cerebral ischemia. To minimize bleeding while keeping antithrombotic activity, we have tried to find an appropriate approach using a combination of platelet integrin GPIIb-IIIa receptor antagonist and some other antithrombotic agents. The time to thrombotic occlusion was measured using a photothrombotic occlusion model of guinea pig middle cerebral artery. A platelet integrin GPIIb-IIIa receptor antagonist, ME3277 (sodium hydrogen [4-[(4,5,6,7-tetrahydrothieno [3,2-c] pyridin-2-yl) carbonylamino] acetyl-o-phenylene] dioxydiacetate), delayed occlusion time from 7.3 min in vehicle to 15.0, 20.6 and 25.9 min (P<0.05) at 0.1, 0.3 and 1 mg/kg, respectively. ME3277 profoundly inhibited ex vivo platelet aggregation and the highest dose of ME3277 prolonged (3.5 folds, P<0.01) the bleeding time measured in the hind paw. A thromboxane A(2) synthase inhibitor, sodium ozagrel, significantly delayed occlusion time to 19.5 min at 30 mg/kg (P<0.05) while it did not affect bleeding time or platelet aggregation. ME3277 (0.1 mg/kg) in combination with 10 mg/kg sodium ozagrel synergistically delayed occlusion time (sodium ozagrel alone; 7.9 min, combination; 26.1 min, P<0.05 vs. ME3277 alone). Sodium ozagrel did not affect ex vivo platelet aggregation or bleeding time when combined with 0.1 mg/kg of ME3277. This synergy was cancelled by combination with 30 mg/kg aspirin (14.7 min). A thromboxane A(2) receptor antagonist, vapiprost (0.1 mg/kg), did not enhance the antithrombotic efficacy of ME3277. These results imply that local prostacyclin production enhances the in vivo antithrombotic effect of the platelet integrin GPIIb-IIIa receptor antagonist. Therefore, the thromboxane A(2) synthase inhibitor allowed a reduction in the dose level of the platelet integrin GPIIb-IIIa receptor antagonist for cerebral thrombosis, which resulted in a reduced risk of bleeding.

Effect of lipo-pro-prostaglandin E1, AS-013 on rat inner ear microcirculatory thrombosis.

We investigated effects of lipo-pro-prostaglandin E1 (lipo-[11alpha, 13E, 15S]-11,15-dihydroxy-9-[1-oxobutoxy]-prosta-8, 13-dien-1-oic acid butyl ester), AS-013 in two models of hearing disturbance and equilibrium dysfunction induced by rat inner ear microcirculatory thrombosis. Inner ear microcirculatory thrombosis was induced by photochemical reaction between systemic injection of Rose Bengal and irradiation of green light to the cochlea and vestibule. Photochemical reaction causes endothelial injury followed by platelet adhesion, aggregation and formation of a platelet- and fibrin-rich thrombus. In the hearing disturbance model, a compound cochlear nerve action potential was recorded by electrocochleography every minute. Photochemical reaction induced inner ear microcirculatory thrombosis, followed by disappearance of the action potential. AS-013 significantly (P<0.05) prolonged time to disappearance of the action potential compared with control group. In the equilibrium dysfunction model, the irradiation to the vestibule was applied for 10 min after Rose Bengal injection. The behavior of rats in the swimming test and nystagmus were observed 24 h after the completion of irradiation. In the swimming test, two of 12 animals treated with AS-013 showed no rotating about their longitudinal axes, which indicates equilibrium dysfunction and the duration of well-balanced swimming prolonged. AS-013 suppressed the appearance of nystagmus. These results suggest that lipo-pro-prostaglandin E1, AS-013 may prevent hearing disturbance and equilibrium dysfunction due to inner ear microcirculatory disorders.

Respiratory effects of halothane and AMPA receptor antagonist synergy in rats.

The influence of N-methyl-D-aspartate (NMDA) or alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptor antagonists in combination with halothane anaesthesia on the respiratory system was investigated. Under 1.5% halothane anaesthesia, respiratory parameters including respiratory rate, minute volume, tidal volume, inspiratory and expiratory duration were measured before and after drug administration in rats. The AMPA receptor antagonists, 6-(1H-imidazol-1-yl)-7-nitro-2,3-(1H,4H)-quinoxalinedione hydrochloride, YM90K (5 and 10 mg/kg) and 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(F)quinoxaline (NBQX, 15 mg/kg), which were administered intravenously for 30 min, significantly reduced the respiratory rate (P < 0.01) and minute volume (P < 0.01) and increased the tidal volume (P < 0.05) compared with values obtained before drug administration. None of these drugs affected respiratory parameters in the absence of anaesthesia. A NMDA receptor antagonist, MK-801 (0.5 mg/kg), which was administered intravenously for 30 min, also significantly reduced respiratory rate (P < 0.01), minute volume (P < 0.01) and tidal volume (P < 0.01) and prolonged inspiratory duration (P < 0.05). These results suggest that both AMPA and NMDA receptor antagonists cause respiratory depression under halothane anaesthesia in rats, although the mechanisms may be different for the two types of antagonists.

Endothelial cell growth factor derived from a human glioblastoma cell line and possible association with tumor angiogenesis.

The cytosol of a human glioblastoma cell line (KNS-42) stimulated the growth of both bovine aortic endothelial cells and smooth muscle cells in a dose-dependent manner. The endothelial cell growth activity eluted at an apparent molecular weight of about 30,000 on a Sephadex G-100 column and bound to a heparin-Sepharose column with high affinity to elute at 1.3-1.7 M NaCl. The growth activity was destroyed by heating at 56 degrees C for 30 min, but not by exposure to trypsin, deoxyribonuclease or ribonuclease at 37 degrees C for 30 min. As this factor stimulated the growth of vascular endothelial cells and smooth muscle cells, and vasoproliferative responses in chick embryo chorioallantoic membranes were apparent, this factor may possibly be related to tumor angiogenesis.

Subarachnoid hemorrhage and granulomatous angiitis of the basilar artery: demonstration of the varicella-zoster-virus in the basilar artery lesions.

A 70-year-old man, with regional herpes zoster (C2) of 10 weeks duration, died following subarachnoid hemorrhage caused by the rupture of an aneurysm in the basilar artery. Granulomatous angiitis, with multinucleated giant cells, was found at autopsy in the wall of the aneurysm. Electron microscopy of the basilar artery disclosed intracytoplasmic viral particles with an envelope which measured 150-220 nm in diameter. Immunohistochemistry studies revealed varicella-zoster-virus-related antigen in the cytoplasm and/or in the nucleus of histiocytes in the vessel wall. These findings suggest that varicella-zoster virus may be linked to the development of granulomatous angiitis.

Leiomyosarcoma of the spermatic cord. A case report and a brief review of literature.

A case of leiomyosarcoma of the spermatic cord, occurring in a 79-year-old male patient, is reported. The tumor was resected with high inguinal ligation and orchiectomy. It was located at the scrotal part of the spermatic cord on the left side and was shown to have originated from the spermatic duct using the dissecting method. Histologically, it was identical to leiomyosarcoma showing a typical morphological appearance of smooth muscle cell tumor in the conventional histochemical preparations as well as a focal positive reaction to antidesmin antibody, a marked nuclear pleomorphism, and abundant mitotic figures. The patient had been untroubled for six months after the resection of the tumor. Leiomyosarcoma arising in spermatic cord is quite rare.

Molecular cloning of an activated human oncogene, homologous to v-raf, from primary stomach cancer.

Transfection with high molecular weight DNA from a primary stomach cancer induced foci of transformed NIH 3T3 cells, and the transformed cells were tumorigenic in nude mice. By screening with a human Alu-family probe, we isolated the human DNA sequence from the secondary transformant cells. This transforming sequence encompasses about 60 kilobase pairs and is unrelated to known human transforming genes. Examination of homologies between this sequence and retroviral oncogenes revealed that the human transforming sequence is closely related to the v-raf oncogene of murine transforming retrovirus 3611-MSV.

Carcinosarcoma of the prostate.

The present report describes a rare prostatic tumor occurring in a 78-year-old Japanese male. The histological features were those of carcinosarcoma involving an adenocarcinoma and a chondrosarcoma, with metastasis to the liver. The carcinomatous component stained positively for prostatic acid phosphatase (PAP) by an immunoperoxidase technique. The literature is reviewed.