Concentration- and Time-Dependent Increase in Specific Airway Resistance after Induction of Airway Hyperresponsiveness by Subchronic Exposure of Guinea Pigs to Nitrogen Dioxide

In the present study utilizing male Hartley guinea pigs, weinvestigated (1) the concentration and time dependency of theeffects of subchronic exposure to nitrogen dioxide (NO₂) onairway responsiveness and (2) the concentration and time dependencyof the effects on specific airway resistance under room air(SRaw₀). Animals were exposed to filtered air, 0.06, 0.5, 1.0,2.0, or 4.0 ppm NO₂ for 6 and 12 weeks (24 hr/day). Airway responsivenessand SRaw₀ were determined 1 week before the beginning of exposureat 10 weeks of age and on the day of termination of the exposure.Our results revealed that (1) subchronic exposure to NO₂ inducesairway hyperresponsive-ness, both concentration and time dependently,(2) such exposure also induces an increase in SRaw₀, both concentrationand time dependently, and (3) subsequent to the airway hyperre-sponsivenessinduced by NO₂ is an increase in the SRaw₀. Therefore, NO₂ couldbe a potent risk factor for alteration of pulmonary functionand airway responsiveness.     

Marked atrophy of the right lobe seen in idiopathic portal hypertension confirmed by laparoscopy

A 70‐year‐old‐male was hospitalized for the treatment of esophageal varices and close examination of the liver. Blood chemistry tests revealed mild liver dysfunction. Abdominal ultrasound and computed tomography scan revealed marked atrophy of the right and quadrate lobes of the liver without abnormalities of the biliary system. Abdominal angiography revealed marked atrophy of the right lobe of the liver, without obliteration in the portal venous system, but it could not be determined whether the atrophy was congenital or secondary. Subsequently performed laparoscopy revealed marked atrophy of the anterior segment of the right lobe and quadrate lobe with the whitish scarred edge demarcating the border between the edge and neighboring liver parenchyma. The liver surface appeared to be undulant, but non‐cirrhotic. These findings suggest secondary lobar atrophy of the liver, without cirrhosis. Liver biopsy of the left lobe showed the findings to be compatible with idiopathic portal hypertension (IPH), and we diagnosed IPH based on these findings and hepatic lobar atrophy was attributable to IPH. There have been few reports of cases with hepatic lobar atrophy associated with IPH, and the mechanism of atrophy is unclear. We report a case of IPH with marked liver atrophy in which laparoscopy is a decisive means whether liver atrophy is congenital or secondary.     

Short sleep duration and long spells of driving are associated with the occurrence of Japanese drivers’ rear‐end collisions and single‐car accidents

Sleepiness and fatigue are important risk factors for traffic accidents. However, the relation between the accident type and lack of sleep as well as spells of driving has not been examined sufficiently. This study aimed to clarify that short sleep duration and long spells of driving are more associated with rear‐end collisions and single‐car accidents as compared with accidents of other types in cases of people who cause accidents. After removing drunken driving as a cause of accidents, 1772 parties involved in accidents were questioned. The quantities of rear‐end collisions and single‐car accidents were, respectively, 240 and 293. Logistic regression analysis showed that short nocturnal sleep (<6 h) and 10‐min increments of spells of driving were significantly associated not only with rear‐end collisions but also with single‐car accidents as compared with accidents of other types. Furthermore, younger age (≤25 years old) and nighttime (21:00–06:00 h) driving were significantly associated with single‐car accidents as compared with accidents of other types. To prevent such accidents, countermeasures must be considered in light of the characteristics of drivers involved in each type of accident described above.     

Clinical significance of serum thymidine kinase in adult T-cell leukaemia and acute myeloid leukaemia

To clarify the clinical and biological significance of serum thymidine kinase (TK) in adult T-cell leukaemia (ATL) associated with human lymphotropic virus type-I (HTLV-I) and in acute myeloid leukaemia (AML), TK was measured in 52 patients with ATL (acute ATL, 35 patients; lymphoma ATL, two patients; chronic ATL, 12 patients; smouldering ATL, three patients), and in 27 patients with AML (one FAB MO, one Ml, 10 M2, seven M3, five M4, one M5, one M6, one MU). In ATL patients, statistical analysis disclosed a close correlation between TK level and the leucocyte count (P<0–01), and absolute number of abnormal lymphocytes (P<0–01). However, no correlation was observed between serum lactic dehydrogenase (LDH) level and these items. Concerning the therapeutic response, a statistical difference was present in TK between complete remission and no response (P<005), but not in LDH. We also investigated a significant inverse correlation between TK level as well as LDH level and the length of survival after the initial diagnosis (P<001). In AML patients a close correlation of TK level with the count of leucocytes (P<001), percentage of blasts in the blood (P<005), therapeutic response (P<0–01) and the length of survival after the initial diagnosis (P< 005) was present.     

Update on Cutting Balloon Angioplasty

Cutting balloon (CB) is a unique balloon catheter with 3 or 4 metal blades on its surface making controlled endovascular surgical incisions that show promise of causing less vessel wall injury and less intimai proliferation. Multicenter randomized trials have revealed that CB angioplasty with multiple inflations achieved better lumen enlargement than single inflation and reduced coronary dissection more than plain old balloon angioplasty (POBA). Follow-up results showed CB angioplasty had a smaller late loss and loss index, resulting in lessened restenosis and target lesion revascularization rates. The main indication of CB angioplasty is basically a noncalcified lesion with concentric plaque; however, it could be applied effectively to some lesions unsuitable for POBA including in-stent restenosis, small vessel, long diffuse lesion, or ostial lesion. Additional evaluation would be necessary to determine the role of CB angioplasty in the stent era.     

Serological and virological markers of human parvovirus B19 infection in patients with haemophilia

Clotting factor concentrates prepared from human plasma are a potential route of parvovirus B19 (B19) infection in patients with coagulation disorders. However, it is not clear whether B19 transmits and persistently infects patients with haemophilia, especially those with HIV infection. We examined serological and virological markers of B19 in samples from 40 patients with haemophilia who had been receiving several brands of clotting factor concentrates. All of them were anti-B19 IgG seropositive and anti-B19 IgM seronegative. The levels of anti-B19 IgG were significantly higher in haemophiliacs than in healthy donors, whereas there was no difference between the level of anti-B19 IgG in haemophiliacs with HIV infection and those without HIV infection. Moreover, there was no difference between the level of anti-B19 IgG in haemophiliacs receiving recombinant factor VIII and that in those receiving plasma-derived clotting factors. Although by using polymerase chain reaction (PCR) B19 DNA was detected at very low levels (< 40 DNA copies mL⁻¹, in 3 out of 40 haemophiliacs, persistent B19 infection was negligible.     

Hyaluronan Facilitates Corneal Epithelial Wound Healing in Diabetic Rats

We investigated the effect of hyaluronan on corneal epithelial wound healing in rats affected by diabetes. Furthermore, because hyaluronan is thought to affect corneal epithelial wound healing through the mechanism of binding of hyaluronan to provisional fibronectin in the wounded area, we compared the localization of fibronectin immunohistochemically during corneal epithelial wound healing in diabetic and non-diabetic rats. Streptozotocin was used to induce diabetes in half the rats. Two weeks after treatment, the whole corneal epithelium of diabetic and untreated rats was debrided. The rats were divided into groups (seven or eight rats per group), and hyaluronan eye drops at concentrations of 0.03, 0.1, or 0.3%, chondroitin sulfate (3%), or phosphate buffered saline (PBS) was given in eye drops 6 times a day for 4 days, starting immediately after debridement. The area of the corneal epithelial wound was measured immediately after debridement and at 12, 18, 24, 30, 48, 72, and 96 hours afterwards. Although the healing process was similar in non-diabetic and diabetic rats, the healing rate in diabetic rats was slower than that in normal controls. In both diabetic and non-diabetic rats, hyaluronan increased the healing rate in a dose-dependent manner; the difference was significant compared with the PBS-treated group, at hyaluronan doses of 0.1% and 0.3%. However, chondroitin sulfate did not affect corneal epithelial wound closure, regardless of whether the rats were diabetic or not; the healing rates were identical to those of PBS-treated diabetic and non-diabetic controls. In both diabetic and non-diabetic corneas, fibronectin was localized in the corneal subepithelial region, and in streaks between collagen fibers of the stroma. One day after debridement, a layer of fibronectin immunofluorescence was clearly visible on the surface of the denuded stroma. As healing progressed staining of fibronectin diminished at the interface between the new epithelium and the stroma. These changes in localization of fibronectin during corneal epithelial wound healing were similar in both diabetic and non-diabetic rats. Our results demonstrate that hyaluronan facilitates corneal epithelial wound healing in diabetic rats, and suggest that one possible mechanism of its stimulatory effect lies in its binding to a provisional fibronectin matrix, in both diabetic and non-diabetic rats.     

Screening for depression among first-visit psychiatric patients: Comparison of different scoring methods for the Center for Epidemiologic Studies Depression Scale using receiver operating characteristic analyses

Abstract The present paper aims to compare the ability of eight scoring methods for the Center for Epidemiologic Studies Depression Scale (CES-D), one of the most widely used self-report inventories for depression, to screen for a major depressive episode. The subjects were 591 patients who constituted representative samples of the first-visit patients to 23 psychiatric hospitals and clinics all over Japan. The criterion diagnoses were given by a semi-structured interview with established inter-rater reliability. The eight alternative scoring methods included the conventional Likert method, which gives the weights 0,1,2 and 3 to the four anchor points of the CES-D; the presence method, which gives the weights 0, 1, 1 and 1, respectively; the GHQ method, which gives the weights 0, 0, 1 and 1, respectively; the persistence method, which gives the weights 0, 0, 0 and 1, respectively; 10-item version, 5-item version, single-item version and the algorithmic method. On the basis of the receiver operating characteristic (ROC) analyses, it was found that the traditional Likert scoring method of the full CES-D performed best in detecting major depressive episodes among first-visit psychiatric patients. The presence method, the GHQ method and the 10-item version appeared to have a similar ability. The persistence method, the 5-item version and the single-item version resulted in significantly worse performance.     

Overview of sudden infant death syndrome in Japan

In spite of rapid medical advancement in the care of infants and children, not only the general public but also many medical personnel have remained unaware of sudden infant death syndrome (SIDS) until very recently in Japan. In 1981, a research project team on SIDS financed by the Ministry of Health and Welfare was founded. Current incidence of SIDS is estimated to be about 0.5 per 1000 live births. The SIDS Family Association was organized in 1993 in Japan and began to publicize the social importance of SIDS and to support SIDS families by training befrienders. A series of articles on current achievements from SIDS research projects and from the SIDS Family Association are submitted to this issue. The present paper summarizes the status of SIDS in Japan by overviewing the activities of the research team and the SIDS Family Association.