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Thermoplastic resins used as a matrix of fiber reinforced thermoplastics (FRTPs) are composed of high polymers that remain highly viscous even at a higher temperature than their melting points. As a result, they need an even higher temperature, a higher pressure and a longer processing time to allow them to bond with fibers that require large and specialized equipment. In contrast, fiber-reinforced thermoset plastics (FRPs) can be easily molded owing to the use of lower viscosity liquid resin as the matrix using simpler devices. In this paper, a new fabrication method of FRTPs using in situpolymerizable ε caprolactam as the matrix is presented. This method uses vacuum-assisted resin transfer molding without the need for large and specialized equipment. The ε-caprolactam molecules were converted from their monomer form into a polyamide 6 resin, with ring-opening polymerization of ε-caprolactam during the molding process at a lower temperature than its melting temperature. The two kinds of FRTPs obtained using ε-caprolactam as the matrix had neither voids nor unfilled parts because ε-caprolactam had a very low viscosity before the polymerization. These FRTPs not only exhibit superior bending properties but also are suitable for high-speed molding, namely, within a few minutes of process time.

The salamander Hynobius yatsui from southwestern Japan was formerly regarded as a small-sized group of H. naevius, but has recently been resurrected as a distinct species. We investigated the phylogeography of H. yatsui from Kyushu Island using partial sequences of the mitochondrial cytochrome b gene. We detected 49 haplotypes in 181 individuals from 24 localities covering the entire geographic distribution of this species on Kyushu. These haplotypes were grouped into two lineages, a northern lineage from northern and central regions, and a southern lineage from the southern region; no haplotypes were shared between the lineages. We surmise that the divergence of the two lineages was induced by volcanic activity that started in the Beppu-Shimabara Graben, between the areas occupied by these two lineages. From the results of a nested clade phylogeographical analysis, we surmise that the high intrapopulation genetic variation observed in the non-volcanic Kyushu Mountains was generated by alternation of contiguous range expansion or long-distance dispersal, and isolation. The current distribution and the observed complicated genetic structures of H. yatsui in Kyushu seem to have been affected first by volcanic activities since the late Pliocene, but subsequent climatic oscillations during the Pleistocene may also have some effects, although it is impossible at this time to differentiate the effects of these two factors. [ABSTRACT FROM AUTHOR]

Abstract: A 72-year-old man was found to have an endobronchial lipoma accompanied with primary lung cancer. A left lower lobectomy with a mediastinal lymph node dissection and a sleeve resection of the lingual bronchus with telescoping bronchial anastomosis were done. The pathological staging was T1N2M0, stage IIIA. A histological examination showed well-differentiated squamous cell carcinoma in segment 10, in addition to the presence of mature adipose tissue which was diagnosed to be a benign endobronchial lipoma originating from the lingual bronchus. The postoperative course was uneventful and the patient was discharged 13 days after the operation. However, he had a recurrence in the subcarinal lymph node, and died 8 months after surgery.

Correspondence to: Kazuhiro Sakata, M.D., Second Department of Surgery, Gunma University School of Medicine, 3-39-15, Showa-machi, Maebashi, Gunma 371, Japan--> Abstract. We investigated the efficacy of University of Wisconsin (UW) solution for its ability to preserve hearts for 12 hours as compared with the results with modified Collins (MC) solution. After orthotopic transplantation, hearts stored in the UW solution (68%) showed significantly (p < 0.05) better recovery of maximum rate of increase of left ventricular pressure than those stored in the MC solution (41%) (MC group: n = 6, UW group: n = 7). The serum CPK values 2 hours after reperfusion were significantly (p < 0.01) higher in the MC group (6528 IU/L) than in the UW group (2021 IU/L). Myocardial adenosine triphosphate (ATP) levels were measured using phosphorus 31 nuclear magnetic resonance spectroscopy during 12 hours of cold storage (MC group: n = 5, UW group: n = 4). ATP levels continued to decrease throughout the storage, and fell to 39% (MC group) and 23% (UW group) of the control after 12 hours with no significant difference. Significant differences between the two groups were present in water content before (MC group: 77.6%, UW group: 75.8%; p < 0.05) and after (MC group: 77.6%, UW group: 75.8%; p < 0.025) 12 hours of storage (MC group: n = 6, UW group: n = 5). These results demonstrated that the UW solution was superior to the MC solution when used to preserve hearts for 12 hours.

Correspondence to: Kazuhiro Sakata, M.D., Second Department of Surgery, Gunma University School of Medicine, 3-39-15, Showa-machi, Maebashi, Gunma 371, Japan--> Abstract. Initial flush for cooling and coronary vascular washout using University of Wisconsin (UW) solution has presented some problems. We used a separate solution for initial flush and for subsequent storage, and evaluated the effect of initial flush for prolonged heart preservation. Following potassium arrest, the initial flush was performed using UW solution (UW group) or Physiol · 3® solution with additional potassium (PK group). In the PK group, an additional flush with the UW solution was done prior to preservation. The hearts of both groups were stored in the cold UW solution for 12 hours. Myocardial high-energy phosphates were measured using phosphorus 31 nuclear magnetic resonance spectroscopy (UW group: n = 7, PK group: n = 5). Adenosine triphosphate (ATP) levels in the UW group decreased to 23% of the control after storage. ATP levels in the PK group were well maintained for up to 6 hours, and then decreased to 51% (p < 0.01). Orthotopic transplantation was performed in 10 pairs of dogs (UW group: n = 7, PK group: n = 3). Preserved grafts in the PK group (74%) tended to show better recovery of left ventricular pressure than those in the UW group (52%). These results suggest that the introduction of an initial flush may prevent ATP level reduction during cold storage, and may provide good results after transplantation. An initial flush for cooling and coronary vascular washout is important for prolonged heart preservation.

To evaluate the prevalence of abdominal aortic aneurysm (AAA) and occlusive peripheral vascular disease (PVD) in Japanese residents, and to examine the correlations between these diseases and the risk factors of atherosclerosis, 348 residents of a village in central Japan aged between 60 and 79 years were screened. The screening for AAA was performed using ultrasonography (US) and that for PVD was performed by palpation and Doppler US. No AAA was found, and a right common iliac arterial aneurysm was detected in a 79-year-old man (0.3%). The mean diameter of the infrarenal abdominal aorta was 18.7 mm and an abdominal aorta of 25 mm or greater in diameter was seen in 16 participants (4.6%), all of whom need to be followed up. PVD was suspected in two patients (0.6%) with a low ankle brachial pressure index. Of a total of five patients diagnosed or suspected of having a common iliac arterial aneurysm or PVD, four (80%) had at least one risk factor for atherosclerosis. Thus, we conclude that Japanese residents with risk factors predisposing them to atherosclerosis such as hypertension, obesity, abnormal serum lipid levels, and a history of smoking should be selectively screened for AAA and PVD due to the low prevalence of these diseases and from the viewpoint of cost-effectiveness.

Abstract: Good exposure and the minimization of lung and thorax injuries are important objectives of surgery for descending thoracic aortic aneurysm (DTAA). In this study, three surgical approaches for DTAA were compared to assess postoperative respiratory function. The subjects were 21 patients with DTAA, three of whom had a thoracoabdominal aneurysm. The mean age was 61 years, and there were 12 men and 9 women. The causes of aneurysm were atherosclerosis in 16 patients, chronic dissection in 4, and traumatic pseudoaneurysm in 1. All the patients underwent femorofemoral partial cardiopulmonary bypass. The DTAA was replaced with a prosthetic graft in 18 patients and repaired with a patch graft in 3. Three approaches were selected, namely, posterolateral thoracotomy (PL group, n = 12), median sternotomy combined with anterolateral thoracotomy (M group, n = 5), and spiral incision (S group, n = 4). There were no significant differences in operation time, cardiopulmonary bypass time, intraoperative blood loss volume, or water balance. The duration of respiratory support and intensive care unit stay were significantly (P < 0.05) longer in the M group than in the other two groups. The alveolar-arterial oxygen difference (AaDO2) and respiratory index (RI) levels immediately after surgery were also significantly (P < 0.05) higher in the M group than in the PL group. There were no significant differences in AaDO2 and RI levels 12 and 24 h after surgery among the three groups. These results suggest that posterolateral thoracotomy is a desirable surgical approach for DTAA repair in view of the fact that it has the least effect on postoperative respiratory function.

The surgical treatment of emphysematous lung bullae is usually contraindicated in patients with severe bronchial asthma. However, we recently encountered a patient who required surgery due to the development of respiratory distress despite treatment with bronchodilators and low-dose prednisolone (5 mg/day). During the first operation, bronchospasm occurred with anesthesia. After suppression of the asthmatic symptoms for 2 weeks with high-dose prednisolone (25 mg/day), the giant bullae could be resected safely. Thus, the preoperative resolution of asthma to decrease the probability of an attack is indispensable for such patients.

A 4-year-old boy was diagnosed as having a chromosomal abnormality with trisomy 3p associated with a secundum atrial septal defect and a cleft of the anterior mitral leaflet. His craniofacial features showed microcephaly, micrognathia, ocular hypertelorism associated with epicanthus, and low-set ears. Moderate mental retardation and hypoplasia of the penis were also noted. A left ventriculogram demonstrated grade 2 mitral regurgitation according to the Sellers' classification with a prolapsing of the mitral leaflets. A cleft of the anterior mitral leaflet was detected at the time of operation. The secundum atrial septal defect was directly closed and the mitral cleft was repaired. This is the first report of trisomy 3p associated with an atrial septal defect and a mitral valve cleft.

Correspondence to: Susumu Ishikawa, M.D., F.I.C.A., Second Department of Surgery, Gunma University School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma, 371, Japan--> Abstract. The correlation between abdominal aortic dilatation and arteriosclerotic risk factors was studied in 2514 Japanese residents (947 men, 1567 women, mean age 70 years old). The aortic diameter was measured by ultrasound and an aortic dilatation was defined as above 30 mm in diameter, including abdominal aortic aneurysm (AAA). Forty-three (1.7%) patients with a dilated aorta and 2471 with a normal-sized aorta were compared. Abdominal aortic dilatation was significantly (p &lt; 0.01) more frequent in men than in women (3% vs 0.7%). Obesity and hyperlipidemia were slightly (p &lt; 0.1) more frequent in patients with a dilated aorta than in those with a normal-sized aorta. There were no significant differences between the two groups in mean age, frequency of smoking, diabetes mellitus, and coronary artery disease. In conclusion, male obesity and hyperlipidemia may be risk factors for aortic dilatation in Japan. Women may not be screened because of cost-effectiveness. The prevalence of aortic dilatation in Japan was lower than in European countries. However, screening for AAA using ultrasound would be advantageous when considering the grave prognoses of ruptured AAA.