High incidence of nitrosamine-induced tumorigenesis in mice lacking DNA repair methyltransferase

The enzyme O6-methylguanine-DNA methyltransferase repairs alkylation- induced DNA damage, O6-methylguanine and O4-methylthymine, the former being formed more frequently. Previously, by means of gene targeting, we generated mice in which alleles for methyltransferase were disrupted. We now use these mouse lines, which are totally deficient in methyltransferase activity, to examine protective effects of the enzyme against tumor formation. In gene-targeted female mice given an i.p. injection of 5 mg/kg of dimethylnitrosamine, a larger number of liver and lung tumors occurred, as compared with normal female mice treated in the same manner. In male mice given a lower dose of carcinogen, the difference between normal and gene-targeted mice was statistically insignificant although more tumors did form in the gene-targeted mice. Methyltransferase apparently afforded protection from nitrosamine- induced tumorigenesis.      

Evaluation of cerebral perfusion from bypass arteries using selective intraarterial microsphere tracer after vascular reconstructive surgery.

BACKGROUND AND PURPOSETo detect areas of cerebral perfusion from bypass arteries after vascular reconstruction, we administered selective intraarterial microsphere tracer into the external carotid arteries and determined (via single-photon emission computed tomography [IA-SPECT]) whether the distribution of radiotracer matched the arteriographic distribution of contrast material as shown on external carotid angiograms.METHODSWe compared the extent of regional distribution of tracer after external carotid artery injection of 20 to 40 MBq of 99mTc-HMPAO or 99mTc-ECD with that of contrast medium on the external carotid angiograms in 582 cortical regions in 12 patients with atherosclerotic occlusive disease and in 18 patients with moyamoya disease.RESULTSMarked accumulation of tracer was found only in the expected, specific, newly developed areas of cerebral perfusion from bypass arteries. The regional distribution of tracer corresponded to that of contrast medium in 523 regions (90%) and did not correspond in 59 regions (10%). Significant overestimation of the distribution of contrast material relative to that of tracer was observed in the patients with moyamoya disease.CONCLUSIONSPECT showed slightly different distribution of tracer from that predicted by conventional angiography. IA-SPECT should enhance the analysis of newly developed areas of cerebral perfusion from the bypass arteries.     

Toxic epidermal necrolysis; 15 years'' experience in a Dutch burns centre

BACKGROUND: Toxic epidermal necrolysis (TEN) is a severe and potentially fatal drug reaction characterized by an extensive skin rash with blisters and exfoliation, frequently accompanied by mucositis. The wounds caused by TEN are similar to second-degree burns and severe cases may involve large areas of skin loss. OBJECTIVES: Analysis of our results in patients with TEN and evaluation of the variety of therapeutic interventions that has been studied and suggested in TEN. PATIENTS/METHODS: Retrospective analysis of 19 consecutive patients with TEN treated in our burns centre between 1989 and 2004. RESULTS: Immediate withdrawal of any potentially fatal drug, maximum supportive care, and a restricted and tailored antibiotic, medical and surgical treatment regimen confined mortality to 21%, whereas prognosis scores like APACHE II and SCORTEN predicted mortality of 22 and 30%, respectively. A positive contribution of selective digestive decontamination is suggested but has yet to be established. CONCLUSIONS: Because of a potentially fatal outcome, fast referral of a patient suspected of TEN to a specialized centre (mostly a burns unit or specialized dermatology centre) for expert wound management and tailored comprehensive care is strongly advised and contributes to survival.     

女性慢性下腹痛的干预性治疗

1背景 育龄妇女常见慢性下腹痛，可造成身体损害、情绪忧伤及导致巨大的健康服务费用。美国在这方面的花费超过8亿8千万美元（Mathias 1996）。英国全国数据库的一般性诊治资料显示，慢性下腹痛发病率及流行率与偏头痛、背部痛、哮喘发病率相似（Zondervan 1999）。     

Meaning in measurement of bone mineral content as preoperative evaluation of aged patients

Recently, mean span of life has been prolonged, and extensive operations are performed on aged patients. However, there are cases which have a difference between their chronological and actual ages. Bone mineral content (BMC) decreases with age and the decrease in BMC might suggest deterioration of immunological competence as observed in osteoporosis. Whether BMC can be an index for evaluation of geriatric patients' actual age from the aspect of immunological competence was investigated. Subjects were 54 cases aged more than 60. Twenty-one healthy young males and females were enrolled as the control group. Quantitative CT is used for assessment of BMC. The value obtained by dividing BMC by the standard BMC of the same age and sex, was defined as BMC index. BMC indices of normal BMC group were more than 0.8 and those of decreased BMC group were less than 0.8. Some immunological markers were investigated. Lymphocyte subset OKT3+ was reduced and juvenile lymphocytes expressed by OKT6+ and OKT3+-(OKT4+ + OKT8+) increased (corrected). Increased in juvenile lymphocyte and decrease in lymphocyte blast transformation and competence of generating interleukin 2 were observed in decreased BMC group. BMC is useful as preoperative evaluation for geriatric operative cases and patients of BMC index below 0.8 need to be paid attention to postoperative infection.     

Closure of a large bronchial fistula with a latissimus dorsi myocutaneous flap

We describe a case of a large bronchial fistula and empyema after right upper lobectomy that was treated successfully with open window thoracostomy followed by a latissimus dorsi myocutaneous flap and limited thoracoplasty. A latissimus dorsi myocutaneous flap can provide immediate airtight closure of a large bronchial fistula, allowing lavage and curettage of the empyema cavity to reduce the chance of postoperative infection. An important aspect of this technique is that the deepithelialized skin side rather than muscle is sutured to an opening of the bronchus. As compared with other techniques, a latissimus dorsi myocutaneous flap is superior in that it requires a single incision and does not require an intraop-erative change of position. In addition, the technique causes little dysfunction of the chest and shoulder and preserves the vascular supply to ensure the viability of the flap even if it was divided in a previous operation.     

Development of a simple image viewer designed for small X-ray field CT equipment 3DX

Objectives To develop a simple image viewer that utilizes image files in general-purpose formats that are written from the original 3DX volume data. Methods We used FLASH MX2004 for Macintosh to develop a simple image viewer. In developing the software for the simple image viewer, we decided that the viewer should provide the following features: (1) be available to both Windows OS and Mac OS, (2) allow interlocking of the 3D images, (3) display image enlargement, and (4) allow distance measurements. The accuracy of the distance measurements was evaluated. Results The procedure was as follows: (1) write 3D images in jpeg format to a folder on i-VIEW; (2) place the folder containing the 3D images into the directory of the simple image viewer software on a PC; (3) start the software and open the window to input the folder name containing the 3D images; and (4) display the 3D images. Our viewer had features such as image enlargement, interlocking 3D images, drawing, and distance measurements. No significant differences were shown between the measurements made by our simple viewer and the actual values of the images in any direction. Conclusions Our image-viewing software for 3DX is beneficial for clinical use.     

Embryonal rhabdomyosarcoma of foot with expansive growth between metatarsals

 The case of a 14-year-old girl with rhabdomyosarcoma of the right foot is reported. Plain radiography showed a large nonspecific soft tissue tumor between the metatarsals with bowing of the metatarsals away from the mass. MR imaging showed a large soft tissue mass involving the metatarsals. The findings were conflicting, because the tumor had an infiltrative soft tissue mass and bowing of the metatarsals more suggestive of slow expansive growth. Bowing of short tubular bones may be a process similar to cortical saucerization, which is typically seen in Ewing’s sarcoma, and it can be one of the findings of high grade neoplasms, such as embryonal rhabdomyosarcoma.