Involvement of apoptosis in the rat germ cell degeneration induced by nitrobenzene

Nitrobenezene (NB) produces germ cell degeneration, especially of spermatocytes in rats. To examine the possible involvement of apoptosis in this process, the extent and nature of nuclear DNA fragmentation after NB dosing were assessed using both terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) and DNA gel electrophoresis, in addition to conventional histological and electron microscopic procedures. Adult Sprague Dawley rats were treated with a single oral dose of NB (250 mg/kg) and euthanized subsequently at 6, 12, and 24 h and 2, 3, 5, and 7 days. The earliest morphological signs of germ cell degeneration in testes were found in pachytene spermatocytes 24 h after dosing. Electron micrographs of degenerating spermatocytes showed marked nuclear chromatin condensation at the nuclear periphery and crowding of cytoplasmic constituents, which are characteristic of apoptosis. Coincident with the appearance of such morphological changes, degenerating spermatocytes contained fragmented DNA as revealed by TUNEL. The presence of DNA laddering, a hallmark of apoptosis on gel electrophoresis, was first apparent and most prominent at 24 h, gradually becoming less detectable. No such changes were observed up to 12 h after dosing or in control animals. These results demonstrated unequivocal involvement of apoptosis in the induction of germ cell degeneration caused by NB. Received: 29 September 1997 / Accepted: 6 January 1998     

High single-dose alternate-day corticosteroid regimens in treatment of polymyositis

Summary High single-dose alternate-day prednisolone therapy (ADT) was compared with daily-dose prednisolone therapy (DDT) for treatment of polymyositis. Thirty patients with polymositis were treated with ADT for an average of 33.9 months. The combined number of improvements was 21 out of 30, a response rate of 70%. Side-effects were very rare and mild. On the other hand, 9 of 17 patients treated with DDT for an average 18.5 months improved, a response rate of 53%. The incidence of side-effects was strikingly higher than with ADT. ADT is therefore strongly advocated for treatment of polymyositis to avoid infectious complications and lessen cushingoid side-effects.     

Hepatic CCR7lowCD62LlowCD45RClow allograft dendritic cells migrate to the splenic red pulp in immunologically unresponsive rats

Donor dendritic cells (DC) migrate into the recipient spleen after hepatic transplantation. Immunological unresponsiveness to rat hepatic allografts can be induced by prior donor-specific blood transfusion (DST). We investigated homing receptor phenotype and splenic distribution of donor DC after allografting and DST. Immunostaining revealed OX62+ cells in the splenic red pulp of animals receiving pre-transplant DST but only in the white pulp of untreated animals. Most OX62 cells were positive for OX76. There were two subsets of DC in the spleen, CD45RChighOX62+ and CD45RClowOX62+ cells. RT-PCR revealed that CD45RClowOX62+ cells expressed interleukin (IL)-10, while CD45RChighOX62+ cells expressed IL-2 and low levels of IL-10 mRNA. CD45RChighOX62+ cells strongly expressed CCR5 and CCR7, compared with weak expression in CD45RClowOX62+ cells. The Epstein-Barr virus-induced molecule 1 (EBI-1) ligand chemokine (ELC/MIP3beta) was expressed mainly within the splenic white pulp. Mucosal vascular addressin-cell adhesion molecule-1 (MAdCAM-1) was expressed in the marginal zone and white pulp, but expression of splenic MAdCAM-1 was down-regulated in DST-treated animals. L-selectin (CD62L), the ligand for MAdCAM-1, was strongly expressed on CD45RChighOX62+ cells but not on CD45RClowOX62+ cells. In conclusion, differential splenic migration of CCR5lowCCR7lowCD62Llow CD45RClow DC expressing Th2-type cytokines is associated with immunological unresponsiveness to rat hepatic allografts.     

Effects of Japan Sea Proper Water on the growth ofLegionella pneumophila, Escherichia coli, andStaphylococcus aureus

Objective To assess whetherLegionella pneumophila serogroup 1 and serogroup 6,Escherichia coli, andStaphylococcus aureus can survive in Japan Sea Proper Water (JSPW). Methods The inhibitory effects of JSPW, surface seawater (SSW), phosphate buffer solution with 3.5% NaCl of pH 7.0 (3.5% NaCIPBS), and the 10²- and 10⁴-fold dilute solutions with purified water or phosphate buffer solution of pH 7.0, and purified water were investigated. Survival cells were counted immediately after the water and the bacteria were mixed, and at 1,3,5, and 7 days after incubation at 37°C. If the number of surviving cells was decreased more than 2 log units compared with the starting value, we judged the medium to have had an inhibitory effect on the growth of the bacteria. Results The survival cells of the bacteria in JSPW had decreased more than 2 log units compared with the starting value at 1 day after incubation. After 1 day of incubation, the cells ofLegionella pneumophila serogroup 6 andStaphylococcus aureus were found to have decreased more than 2 log units in purified water (PW) used as a control. Furthermore,Legionella pneumophila serogroup 1 in the 10²-fold dilute solution of JSPW was only 1.04 log units lower than the starting value at 7 days after incubation. In the 10²- and 10⁴-fold dilute solutions of JSPW,Escherichia coli survived for 7 days after incubation. These results were almost similar to the results in SSW and 3.5% NaCIPBS. Conclusions The present findings demonstrate thatLegionella pneumophila serogroup 1 andEscherichia coli cannot survive in undiluted JSPW for over a day at 37°C, suggesting the inhibitory effects may be due to the sodium chloride contained in JSPW.     

Health characteristics of elderly Japanese requiring care at home

The number of elderly subjects requiring care is rapidly increasing, however, their health status has not been well studied. The purposes of this study were to describe the health characteristics of the elderly at home who were using long-term care insurance, and to clarify factors that influence dependence for activities of daily living (ADL). The subjects were 194 elderly people living at home, who were approved for care. The items surveyed were the demographic characteristics, care level (or level of dependence for ADL), Barthel index, grip strength, thigh muscle volume, cognitive impairment using the mini-mental state examination (MMSE), depressed mood using the geriatric depression scale (GDS-15), and serum albumin and hemoglobin levels. The grip strength (p=0.0001), thigh muscle volume (p=0.0030), MMSE score (p=< 0.0001) and serum albumin level (p= < 0.0001) decreased, while the GDS-15 score (p=0.0142) increased with deteriorating care levels. The proportion of subjects not requiring assistance for the items "bathing" and "stair-climbing" in the Barthel index was markedly low in the subjects belonging to the relatively low (mild) care levels. The logistic regression analysis showed that factors associated with dependence for "bathing" and "stair-climbing" were the use of day-services, male sex, decline of grip strength, and a high GDS-15 score. In conclusion, it is important to strengthen the muscles of the upper half of the body, and to correct depressed moods for maintaining levels of ADL in the elderly requiring care at home.     

Factors affecting short-term mortality in very low birth weight infants in Japan

No epidemiological surveys have examined risk factors related to the death of very low birth weight infants (VLBWIs) in Japan. The objectives of this study were to examine the death rate and fatalities related to complications among VLBWIs, and to analyze factors possibly determining the death of VLBWIs. The subjects of this study were 811 VLBWIs admitted to the Neonatal Care Center of Niigata City General Hospital between April 1987 and March 2003. We obtained information on gender, birth weight, gestational age, Apgar scores, single/multiple pregnancy, postnatal transfer, mode of delivery, complications and outcome (alive or deceased) at the time of discharge from medical records. Of the 811 infants, 98 died prior to discharge (12.1%). Logistic regression analysis showed that independent risk factors for death of VLBWIs were male gender (relative risk [RR]: 2.0), low birth weight (RR: 0.56), necrotizing enterocolitis (RR: 58.0), pulmonary hypoplasia (RR: 37.8), chromosomal abnormalities (RR: 36.3), congenital heart diseases (RR: 9.8), persistent fetal circulation (RR: 9.6), neonatal asphyxia (RR: 6.3) and sepsis (RR: 4.4). The risk for death rises 1.8-fold if birth weight decreases by 100 g. A very high risk of perinatal death is associated with necrotizing enterocolitis, pulmonary hypoplasia or chromosomal abnormalities. The risk of death due to congenital heart diseases or neonatal asphyxia is relatively lower, but the incidences of these two disorders are high (8% and 6%, respectively). From the viewpoint of prophylactic treatment aimed at reducing the death rate of VLBWIs, measures to increase birth weight are of primary importance. Furthermore, early treatment and improved perinatal management of congenital heart diseases and neonatal asphyxia are anticipated to reduce the overall death rate of VLBWIs.     

Characteristic Sliding Frictional Behavior on the Surface of Nanocomposite Hydrogels Consisting of Organic‐Inorganic Network Structure

Summary: Sliding frictional behavior on the surface of novel nanocomposite hydrogels (NC gels), composed of poly(N‐isopropylacrylamide) and exfoliated clay, was investigated and compared with that of conventional chemically‐crosslinked hydrogels (OR gels). Since OR gels are so weak, the sliding test, in general, could not be carried out on their surfaces except when wet. On the contrary, NC gels can withstand sliding friction under high loading and it was found that the frictional forces are sensitive to the environmental surroundings (wet or in‐air), the gel composition (water, clay contents), and loading. In air, NC gels exhibit a characteristic force profile with a maximum static frictional force (max‐SFF) and subsequent constant dynamic frictional force. In contrast, NC gels exhibit very low frictional forces under wet conditions. The change in frictional force with surroundings was very distinctive for NC gels, particularly for those with low clay contents. Max‐SFF for NC1 gel decreased more than 100‐fold by changing the environment from in‐air to wet. The characteristic sliding frictional behaviors are explained on the basis of a unique organic/inorganic network structure of NC gels.

The model of sliding process on NC gel and effects of clay content of NC gels on the sliding frictional behavior.     

Gallbladder carcinoma presenting as exfoliative dermatitis (erythroderma)

Although exfoliative dermatitis (erythroderma) secondary to malignancy is commonly associated with lymphomas or leukemias, coincident gastrointestinal (GI) malignancy and erythroderma is rare. The authors recently encountered a patient with gallbladder carcinoma presenting as erythroderma. A 77-yr-old Japanese man presented with a 3-mo history of erythematous eruptions with pruritus over almost the entire body. After confirming the diagnosis of erythroderma, asymptomatic gallbladder carcinoma was found. Further investigations detected no malignancies in other organs. An extended cholecystectomy was performed. Histologic examination of resected specimens revealed poorly differentiated adenocarcinoma with negative resection margins. The eruptions with pruritus resolved within 1 wk after the operation. This is the first report, to our knowledge, of coincident biliary malignancy and erythroderma. The experience of the current patient suggests that erythroderma secondary to GI malignancy may resolve spontaneously after curative resection of the tumor.