Search for bosonic superweakly interacting massive dark matter particles with the XMASS-I detector

Bosonic superweakly interacting massive particles (super-WIMPs) are a candidate for warm dark matter. With the absorption of such a boson by a xenon atom, these dark matter candidates would deposit an energy equivalent to their rest mass in the detector. This is the first direct detection experiment exploring the vector super-WIMPs in the mass range between 40 and 120 keV. With the use of 165.9 day of data, no significant excess above background was observed in the fiducial mass of 41 kg. The present limit for the vector super-WIMPs excludes the possibility that such particles constitute all of dark matter. The absence of a signal also provides the most stringent direct constraint on the coupling constant of pseudoscalar super-WIMPs to electrons. The unprecedented sensitivity was achieved exploiting the low background at a level 10(-4)  kg-1 keVee-1 day-1 in the detector.

[Emergency CABG for patients with LMT lesion treated by mechanical cardiac support]

We retrospectively analysed the perioperative course of 22 patients who underwent emergency CABG for severe left main trunk lesion. The causes of LMT lesion were spontaneous acute myocardial infarction in 14 patients and failed coronary intervention and coronary angiography in 8 patients. IABP was used preoperatively in all patients and additional coronary perfusion catheter were induced for two patients and PCPS was for one patient. Overall incidence in-hospital operative mortality was 22.7% (5/22), four of them were due to cardiac related causes and one of them was due to acute renal failure. Postoperative level of max CPK enzyme was significantly higher in death cases compared to survivors, 6,330 +/- 3,649 versus 1,299 +/- 1,417 IU/dl. We considered that the most important factors in surgical strategy for acute coronary syndrome with LMT lesion were as follows: improvement of hemodynamics with mechanical cardiac support by IABP or/and PCPS, protection of broad myocardial ischemia using coronary perfusion catheter and urgent surgical revascularization by emergency CABG.

[A case of paragonimiasis with a tumor of the intrathoracic chest wall]

A case of paragonimiasis with a tumor of intrathoracic chest wall was reported. The patient was a 46-year-old male who complained of cough and showed abnormal findings on chest X-ray. After performing various examinations, the patient was diagnosis as having a tumor of the intrathoracic chest wall. On surgery, the tumor was enveloped in a thick capsule and its lumen was filled with yellow-white atheromatous material. Calcification was not found. Pathologically, an egg-like structure of a parasite was confirmed inside the sequestrum attached to the lining of the inner surface of the capsule. Past history of pleuritis and ingestion of freshwater crabs confirmed the diagnosis of paragonimiasis.

[A case of cardiac angiosarcoma with a pseudoaneurysm formed in the right coronary artery]

A case of superficially infiltrating cardiac angiosarcoma damaging the right coronary artery and forming a pseudoaneurysm was studied. The patient was a 25-year-old male who had undergone cardiac tamponade twice in the past six months. Since heart murmur was audible in auscultation, thorough examination was performed. Cardioechography and cardiac angiography revealed a pseudoaneurysm of hen egg size involving the proximal right coronary artery. Although the pseudoaneurysm and right atrium ruptured during operation, a coronary bypass was placed and the right atrium was repaired with an equine pericardium. Angiosarcoma was identified by pathological examination of the excised specimen. The patient died two months after operation due to lung metastasis.

[A case report of aortic valve and VSD Dacron patch infective endocarditis after VSD patch closure 15 years ago]

A 39-year-old man who had undergone the patch closure of the VSD 15 years ago, was admitted with a diagnosis of infective endocarditis due to Alcaligenes Xylosoxidans. Echocardiography revealed vegetation of the aortic valve and a high echoic lesion on the ventricular septum. Surgical findings showed vegetation of the aortic valve and a subannular type mycotic aneurysm. In the aneurysm, the infected pledget used in a previous surgery was found. After debridement, direct closure of the aneurysm, aortic valve replacement (AVR) using a #25 SJM prosthetic valve, and mitral annuloplasty were performed. Two months later, fever developed. The patient was diagnosed with prosthetic valve endocarditis and a second surgery was performed. The prosthetic valve was clear, but an infected Dacron patch used for VSD closure 15 years earlier was found. Debridement, patch closure of the ventricular septum, and re-AVR were performed. The post-operative course was uneventful. This is thought to be a rare case, because infection extended from the aortic valve to the VSD type II Dacron patch, and remained to the VSD type II Dacron patch.

[Emergency coronary artery bypass grafting for failed percutaneous transluminal coronary angioplasty]

There were 1151 patients who underwent PTCA at our facilities from August 1984 to December 1990. The records of 298 patients were reviewed from August 1984 to June 1988 (former period), and were compared with records of 853 patients undergoing treatment after June 1988 (latter period). Of 852 elective PTCA procedures, complete occlusion of the lesion increased from 2.3% in the former period to 17.5% in the latter period, while for partial occlusion there were 60.4% in the former and 60.5% in the latter. Emergency PTCA for acute myocardial infarction decreased from 37.2% in the former to 22% in the latter. The number of patients with multivessel disease increased slightly from 43.6% in the former to 46.8% in the latter. The success rate for patients who underwent elective PTCA for complete occlusion was 42.8% in the former and 49.6% in the latter, while for partial occlusion it was 87.2% in the former and 91.8% in the latter. The success rate for patients requiring emergency PTCA was 73.8% in the former and 90.4% in the latter. Of the patients undergoing elective PTCA, acute coronary closure occurred in 3% of the former and in 1% of the latter, while for patients requiring emergency PTCA, there were 4.4% in the former and 2.7% in the latter. Of the 8 patients who required emergency CABG, elective PTCA was unsuccessful in 4 cases and emergency PTCA was also unsuccessful in the other 4; in other words, 4 of a total 852 elective PTCAs (0.47%) and 4 of 299 emergency PTCAs (1.3%) for an overall figure of 8/1151 (0.7%).(ABSTRACT TRUNCATED AT 250 WORDS)

[A surgical case of cor triatriatum complicated by arterial multiple embolism in adult]

A 30 year old male developed sudden chest pain while driving his car and was subsequently admitted to our hospital. Cardiac catheterization and arteriography revealed multiple embolism in the right coronary artery, the right renal artery and the both popliteal arteries. Thrombus was also suspected in the left atrium by echocardiography. Emergent surgery was performed to prevent recurrence of embolism, IA type cor triatriatum (according to the Lucus-Schmidt classification) and 3 x 1 cm thrombus in the accessory chamber was found. The thrombus was extracted and the abnormal septum was satisfactorily resected. The postoperative course was favourable and the patient returned to the community after discharge. Cases of cor triatriatum complicated by multiple arterial embolism are very rare and have not been reported in Japan yet. For this reason we present this case with additional discussion from literature.

[A surgical case of left coronary artery-left ventricular fistula]

Left ventricular fistulas arising from the left coronary artery are rare, and only 3 cases have been reported Japan. Surgical closure of a left coronary artery-left ventricular fistula in a 14-year old male was reported. The fistula was identified by coronary arteriography after the patient had been admitted to hospital complaining of recurrent chest pain. Ligation of the fistula involving the left anterior descending coronary artery was performed with cardiopulmonary bypass, chemical arrest and hypothermia. The blood flow through the LAD decreased from 370 ml/min to 100 ml/min after the fistula was ligated, and there was uneventful postoperative recovery. Furthermore chest pain of the patient was shown to diminish and movement of the left ventricular septum was improved, compared with the preoperative cineangiography. However, trivial residual flow fo the circumflex coronary artery to the left ventricle remained on postoperative coronary arteriography. The principal aim of the procedure for surgical correction should be effective closure of the fistula without compromising the distal blood supply of the coronary artery involved, cardiopulmonary bypass is considered necessary to appropriate closure of the fistula.

[A case of right intermediate bronchial stenosis due to an injury eighteen years before]

A 20 year-old man was admitted to our hospital suffering from fever and cough due to bronchiectasis. He had been injured in automobile accident 18 years before. The subsequent bronchography revealed a marked stricture of the right intermediate bronchus with post-stenotic bronchiectasis. Right middle and lower lobectomy was performed. Postoperatively, pneumonia improved, and pulmonary function was preserved. There is no agreement on criteria indicating the need for bronchial reconstruction in cases like this, because evaluation is difficult whether inflammatory changes in the lobes intending to the reimplant may be reversible. In our case, we considered that recurrent pneumonia and bronchiectatic changes of the right lower lobe were contra-indications to bronchial reconstruction.