HLA-DR2 frequency increase in severe aplastic anemia patients is mainly attributed to the prevalence of DR15 subtype

The association between severe aplastic anemia (AA) and DR2 antigen seems to be well established. However, since discrimination between two DR2-associated splits, namely DR15 and DR16, rarely was performed, it remains unclear whether one or both of these subvariants are responsible for AA susceptibility. In this study, we have analyzed the HLA-DR allelic distribution in a group of 37 AA patients of slavic origin from North-Western Russia. The experimental design included PCR-based amplification of DRB-specific sequences, followed by reverse dot-blot hybridization of the biotinylated PCR-product with the set of sequence-specific oligonucleotide probes. HLA-DRB alleles were identified by non-radioactive enzymatic reaction, then standard serological specificities of HLA-DR antigen were estimated according to the WHO nomenclature. Whereas DR15 subtype occurred more often in the patients (23.0% vs. 13.3%, p< 0.05), DR16 split did not show the same tendency. The results, show the overall predominance of HLA-DR2 specificity (DR15+DR16) did not reach statistical significance (24.4% vs.17.5%, p<0.2). Thus, we conclude that repeatedly reported DR2 frequency increase in AA patients is mainly attributed to the prevalence of DR15 subtype.     

Factors influencing joint-preserving operations in the treatment of the late stages of osteoarthritis of the hip

Between November 1983 and December 1992, 136 hips (119 patients) with coxarthritis were operated on using joint-preserving techniques based on the rationale of Pauwels' osteotomy. The criterion for selection was a patient in whom the height of the joint space in the weight-bearing area of the hip was less than 1 mm. The mean age at operation was 48 years and the mean follow-up 109 months (60 to 171). Hips were categorised using Bombelli's classification of osteoarthritis, into atrophic and non-atrophic types. The endpoint was defined as that at which the height of the joint space became less than 1 mm again. The Kaplan-Meier curve showed that the rate of survival of the non-atrophic group was significantly better than that of the atrophic group. Cox's proportional hazard model indicated that the factors influencing the results of joint-preserving operations included Bombelli's classification, postoperative incongruence of the joint and the height of the joint space.     

Two-stage hepatectomy for multiple bilobular liver metastases from colorectal cancer

BACKGROUND/AIMS: To determine an appropriate surgical treatment for patients with multiple liver metastases, we evaluated the efficacy of two-stage hepatectomy in patients with multiple bilobular liver metastases from colorectal carcinoma. METHODOLOGY: Some patients with multiple liver metastases are not candidates for a complete resection by a single hepatectomy, even when downstaged by chemotherapy, after portal embolization. In two-stage hepatectomy, the highest possible number of tumors is resected in a first, noncurative intervention, and the remaining tumors are resected after a period of liver regeneration. Two-stage hepatectomy was performed in 11 patients. RESULTS: Two-stage hepatectomy was feasible in all of the 11 patients. In 3 of them, the first stage was a major resection (more extensive than a lobectomy). This first hepatectomy was uneventful in all patients. The second hepatectomy was also uneventful in nine patients, but in one of the other two, a perihepatic fluid infection occurred, and in the other, postoperative liver failure developed due to a right subphrenic abscess. However, all patients were discharged. The percentage of the expected resection volume at one time, calculated from CT volumetry, was 75.5+/-1.2% and the prognostic score as surgical risk was 56.6+/-4.5. In two-stage hepatectomy cases, the percentage of the resected volume and the prognostic score in the first hepatectomy were 25.4+/-6.4% and 6.7+/-7.3, and in the second, 45.7+/-4.5% and 28.5+/-5.8. During the follow-up procedures, a residual hepatic recurrence was observed in 6 patients, and pulmonary recurrence in 9. The 1- and 3-year survival rates after the first hepatectomy were 90% and 45%, with median survivals of 18 months from the first hepatectomy. CONCLUSIONS: Two-stage hepatectomy is a surgical modality intended for patients with initial unresectable metastases. However, following such surgery, protective treatment against residual liver recurrence and lung metastasis will be a most important issue.     

Myocardial bridging increases the risk of coronary spasm

BACKGROUND: Myocardial bridging (MB) has been associated with cardiac events. Whether coronary spasm is one factor contributing to those events is unknown. HYPOTHESIS: This study investigated whether the likelihood of coronary spasm is increased in patients with MB. METHODS: A spasm-provocation test was performed by infusing acetylcholine into the left coronary artery in 114 Japanese patients with chest pain. The test result was defined as positive when the diameter of the coronary artery was reduced by > or = 50% and ST-segment changes were documented. Myocardial bridging was defined as a > 15% reduction in coronary arterial diameter during systole after intracoronary injection of nitroglycerin. RESULTS: Myocardial bridging was identified in 41 patients (36%) and was located in the mid-segment of the left anterior descending coronary artery (LAD) in all patients. Patients with MB experienced coronary spasm more frequently than patients without MB (MB+: 73%; MB-: 40%, p = 0.0006). Furthermore, among patients with a positive spasm-provocation test, coronary spasm occurred more frequently in the mid-segment of the LAD in patients with MB than in those without MB (MB+: 73%; MB-: 45%, p = 0.0259). Multivariate regression analysis demonstrated that MB was a predictor of coronary spasm (odds ratio: 3.478, p = 0.0088). CONCLUSIONS: These results suggest that MB increases the risk of coronary spasm and that coronary spasm may be the proximate etiology of cardiac events associated with MB.     

MPO-ANCA-positive slowly progressive glomerulonephritis with focal tuft necrosis and crescents

A 37-year-old woman had been found to have proteinuria in October 1996. About 8 months later, the first renal biopsy was performed, revealing focal segmental necrotizing and crescentic glomerulonephritis. At that time, serum creatinine was 1.0 mg/dl and urinary protein 3+. In October 1999, laboratory tests revealed positivity for MPO-ANCA and a serum creatinine level of 1.42 mg/dl, anemia and proteinuria of 2+. A second renal biopsy showed almost the same histological findings. Accordingly, a diagnosis of MPO-ANCA positive glomerulonephritis was made. This patient was thought to be a rare case of MPO-ANCA-positive slowly progressive glomerulonephritis presenting focal segmental tuft necrosis and crescents.     

Amebic colitis in asymptomatic subjects with positive fecal occult blood test results: clinical features different from symptomatic cases

Amebiasis is a common parasitic infectious disease in developing countries. In developed countries, it is occasionally encountered in travelers to the tropics and in homosexual males. During the past eight years, we detected four cases of amebic colitis among 5,193 subjects who underwent colonoscopy because of positive fecal occult blood test results in a mass screening. All four cases did not have any abdominal symptoms. Ulcerative lesions were observed only in the cecum and ascending colon; another portion of the colon and rectum appeared normal. We may encounter amebic colitis during colonoscopic examination even in subjects who are asymptomatic.     

Primary malignant peripheral nerve-sheath tumor of the common bile duct

Primary malignant peripheral nerve-sheath tumors of the common bile duct are extremely rare. To our knowledge, the published literature contains no previous case report of this disease. Here we report on a 58-year-old Japanese woman with a primary malignant peripheral nerve-sheath tumor of the common bile duct, which was completely resected. A hypoechoic mass was identified in the hepatic hilus, using ultrasonography and computed tomography. Endoscopic retrograde cholangiography revealed a smooth stricture and deviation of the common bile duct. Laparotomy exposed a firm mass around the common bile duct that had not invaded the surrounding tissues. Partial resection of the common bile duct and cholecystectomy were performed as the treatment of choice. The final histopathological diagnosis was malignant peripheral nerve-sheath tumor arising from the wall of the common bile duct.     

Associations between sleep habits and mental health status and suicidality in a longitudinal survey of monozygotic twin adolescents

Several epidemiological studies have indicated that there is a relationship between sleep habits, such as sleep duration, bedtime and bedtime regularity, and mental health status, including depression and anxiety in adolescents. However, it is still to be clarified whether the relationship is direct cause‐and‐effect or mediated by the influence of genetic and other traits, i.e. quasi‐correlation. To examine this issue, we conducted a twin study using a total of 314 data for monozygotic twins from a longitudinal survey of sleep habits and mental health status conducted in a unified junior and senior high school (grades 7–12), located in Tokyo, Japan. Three‐level hierarchical linear model analysis showed that both bedtime and sleep duration had significant associations with the Japanese version of the 12‐item General Health Questionnaire (GHQ‐12) score, suicidal thoughts and the experience of self‐harm behaviours when genetic factors and shared environmental factors, which were completely shared between co‐twins, were controlled for. These associations were statistically significant even after controlling for bedtime regularity, which was also associated significantly with the GHQ‐12 score. These suggest that the associations between sleep habits and mental health status were still statistically significant after controlling for the influence of genetic and shared environmental factors of twins, and that there may be a direct cause‐and‐effect in the relationship in adolescents. Thus, late bedtime and short sleep duration could predict subsequent development of depression and anxiety, including suicidal or self‐injury risk. This suggests that poor mental health status in adolescents might be improved by health education and intervention concerning sleep and lifestyle habits.     

Change of a motor synergy for dampening hand vibration depending on a task difficulty

The present study investigated the relationship between the number of usable degrees of freedom (DOFs) and joint coordination during a human-dampening hand vibration task. Participants stood on a platform generating an anterior–posterior directional oscillation and held a water-filled cup. Their usable DOFs were changed under the following conditions of limb constraint: (1) no constraint; (2) ankle constrained; and (3) ankle–knee constrained. Kinematic whole-body data were recorded using a three-dimensional position measurement system. The jerk of each body part was evaluated as an index of oscillation intensity. To quantify joint coordination, an uncontrolled manifold (UCM) analysis was applied and the variance of joints related to hand jerk divided into two components: a UCM component that did not affect hand jerk and an orthogonal (ORT) component that directly affected hand jerk. The results showed that hand jerk when the task used a cup filled with water was significantly smaller than when a cup containing stones was used, regardless of limb constraint condition. Thus, participants dampened their hand vibration utilizing usable joint DOFs. According to UCM analysis, increasing the oscillation velocity and the decrease in usable DOFs by the limb constraints led to an increase of total variance of the joints and the UCM component, indicating that a synergy-dampening hand vibration was enhanced. These results show that the variance of usable joint DOFs is more fitted to the UCM subspace when the joints are varied by increasing the velocity and limb constraints and suggest that humans adopt enhanced synergies to achieve more difficult tasks.