Joint unloading inhibits articular cartilage degeneration in knee joints of a monosodium iodoacetate-induced rat model of osteoarthritis

OBJECTIVE

The aim of the study was to examine how mechanical unloading affects articular cartilage degeneration in the patellofemoral (PF) and tibiofemoral (TF) joints of a monosodium iodoacetate (MIA)-induced rat model of osteoarthritis (OA).

DESIGN

The study involved 60 male rats. OA was induced by intra-articular injecting MIA into both knee joints. All animals were equally divided into two groups: sedentary (SE) and hindlimb unloading (HU) groups. Histopathological changes in the articular cartilage of the PF and TF joints were evaluated using the Osteoarthritis Research Society International (OARSI) score and modified Mankin score at 2 and 4 weeks after MIA injection.

RESULTS

In the SE and HU groups, representative histopathological changes in OA were detected in the PF and TF joints. The OARSI and modified Mankin scores for the PF and TF joints tended to increase over time after the injection of 0.2 mg or 1.0 mg of MIA in the SE and HU groups. Both the scores for the HU group were significantly lower than those for the SE group [OARSI score: P < 0.0001 (1.0-mg injection at 4 weeks); modified Mankin score: P = 0.0116 (0.2-mg injection at 4 weeks); P = 0.0004 and < 0.0001 (1.0-mg injection at 2 and 4 weeks, respectively)].

CONCLUSION

This study revealed new histological evidence that indicates that unloading condition suppresses articular cartilage degeneration and is beneficial in many areas of basal and clinical research involving OA.

Physiological exercise loading suppresses post-traumatic osteoarthritis progression via an increase in bone morphogenetic proteins expression in an experimental rat knee model

OBJECTIVE

To evaluate the dose-response relationship of exercise loading in the cartilage-subchondral bone (SB) unit in surgically-induced post-traumatic osteoarthritis (PTOA) of the knee.

DESIGN

Destabilized medial meniscus (DMM) surgery was performed on the right knee of 12-week-old male Wistar rats, and sham surgery was performed on the contralateral knee. Four weeks after the surgery, the animals were subjected to moderate (12 m/min) or intense (21 m/min) treadmill exercises for 30 min/day, 5 days/week for 4 weeks. PTOA development in articular cartilage and SB was examined using histological and immunohistochemical analyses, micro-computed tomography (micro-CT) analysis, and biomechanical testing at 8 weeks after surgery. Gremlin-1 was injected to determine the role of bone morphogenetic protein (BMP) signaling on PTOA development following moderate exercise.

RESULTS

Moderate exercise increased BMP-2, BMP-4, BMP-6, BMP receptor 2, pSmad-5, and inhibitor of DNA binding protein-1 expression in the superficial zone chondrocytes and suppressed cartilage degeneration, osteophyte growth, SB damage, and osteoclast-mediated SB resorption. However, intense exercise had little effect on BMP expression and even caused progression of these osteoarthritis (OA) changes. Gremlin-1 injection following moderate exercise caused progression of the PTOA development down to the level of the non-exercise DMM-operated knee.

CONCLUSIONS

Exercise regulated cartilage-SB PTOA development in DMM-operated knees in a dose-dependent manner. Our findings shed light on the important role of BMP expression in superficial zone chondrocytes in attenuation of PTOA development following physiological exercise loading. Further studies to support a mechanism by which BMPs would be beneficial in preventing PTOA progression are warranted.

Thinning of articular cartilage after joint unloading or immobilization. An experimental investigation of the pathogenesis in mice

OBJECTIVE

Moderate mechanical stress generated by normal joint loading and movement is essential for the maintenance of healthy articular cartilage. However, the effects of reduced loading caused by the absence of weight bearing or joint motion on articular cartilage and subchondral bone is still poorly understood. We aimed to characterize morphological and metabolic responses of articular cartilage and subchondral bone to decreased mechanical stress in vivo.

METHODS

Mice were subjected to periods of hindlimb unloading by tail suspension or external fixation of the knee joints. The articular surface was observed with digital microscope and the epiphyseal bone was assessed by micro-CT analysis. Articular cartilage and subchondral bone were further evaluated by histomorphometric, histochemical, and immunohistochemical analyses.

RESULTS

The joint surface was intact, but thickness of both the total and uncalcified layer of articular cartilage were decreased both after joint unloading and immobilization. Subchondral bone atrophy with concomitant marrow expansion predisposed osteoclast activity at bone surface to invade into cartilaginous layer. Uncalcified cartilage showed decreased aggrecan content and increased aggrecanase expression. Alkaline phosphatase (ALP) activity was increased at uncalcified cartilage, whereas decreased at calcified cartilage. The distributions of hypertrophic chondrocyte markers remained unchanged.

CONCLUSION

Thinning of articular cartilage induced by mechanical unloading may be mediated by metabolic changes in chondrocytes, including accelerated aggrecan catabolism and exquisitely modulated matrix mineralization, and cartilage matrix degradation and resorption by subchondral osteoclasts. Cartilage degeneration without chondrocyte hypertrophy under unloading condition indicate the possible existence of mechanism which is different from osteoarthritis pathogenesis.

Exercise intervention increases expression of bone morphogenetic proteins and prevents the progression of cartilage-subchondral bone lesions in a post-traumatic rat knee model

OBJECTIVE

This study aimed to determine whether treadmill walking (TW) prevents the progression of post-traumatic osteoarthritic changes in cartilage-subchondral bone unit, and whether the exercise timing changes the exercise efficacy in destabilized medial meniscus (DMM) rat knees.

DESIGN

Twelve-week-old male Wistar rats underwent DMM surgery on their right knees and sham surgery on their left knees and were assigned to either the sedentary (n = 10) or walking (n = 24) groups. The rats in the walking group were subjected to TW from day 2 through 4 weeks, from 4 through 8 weeks, or from day 2 through 8 weeks (n = 8 per group). Osteoarthritic changes of cartilage and subchondral bone were assessed with micro-computed tomography, histology, and immunohistochemistry 8 weeks after surgery.

RESULTS

TW prevented the progression of cartilage and subchondral bone lesions induced by the DMM, and increased bone morphogenetic protein (BMP)-2 and -6 expressions in superficial zone chondrocytes and bone-lining cells including osteoblasts. Furthermore, the TW-induced increase in BMPs varied with the exercise timing. Beginning TW 4 weeks after DMM surgery was the best option for increasing BMPs, coinciding with the most robust prevention of osteoarthritic changes.

CONCLUSIONS

TW increased the expression of BMPs and prevented the progression of cartilage-subchondral bone lesions in rat knees with a DMM. Selective exercise timing may be a key factor in the development of an exercise regimen for preventing the progression of post-traumatic osteoarthritis (PTOA). Furthermore, exercise may have favorable effects even after the PTOA has been developed.

Subchondral plate porosity colocalizes with the point of mechanical load during ambulation in a rat knee model of post-traumatic osteoarthritis

OBJECTIVE

This study investigated the association between spatiotemporal cartilage-subchondral bone plate alterations and mechanical load during ambulation in an experimental rat model of destabilized medial meniscus (DMM).

DESIGN

Twelve-week-old Wistar rats (n = 38) underwent DMM surgery on the right knee and sham surgery on the left knee. At 2 and 4 weeks after surgery, subchondral bone changes were evaluated via micro-computed tomography with various knee flexion angles to simulate weight-bearing during rat ambulation under a 3-dimensional motion capture apparatus. Additionally, the biomechanical properties, histology, and ultrastructure of the medial tibia and femoral condyle were evaluated.

RESULTS

Focal subchondral bone plate perforations were confirmed in the medial tibia within 2 weeks after surgery and were aggravated rapidly 2 weeks later. This subchondral plate porosity colocalized with articular cartilage lesions as confirmed by histology and scanning electron microscopy, and coincided with the likely point of contact between the posterior femoral condyle and tibial plateau during ambulation. Biomechanical properties were confirmed at the medial tibia, at which stiffness was reduced to approximately half that of the sham-operated knee at 4 weeks after surgery.

CONCLUSIONS

Cartilage-subchondral bone plate alterations localized in the region of the point of mechanical load during ambulation in DMM-operated knees, at which the mechanical integrity of cartilage was impaired. These results indicate that DMM-induced increases in mechanical load play an important role in the pathogenesis of early post-traumatic osteoarthritis (OA), and it might accelerate the development of the disease via cartilage-subchondral bone plate crosstalk through increased subchondral plate perforations.

Effects of short-term gentle treadmill walking on subchondral bone in a rat model of instability-induced osteoarthritis

OBJECTIVE

Subchondral bone cyst (SBC) growth, caused by osteoclast activity during early knee osteoarthritis (OA) pathogenesis, should be treated to prevent further progressions of OA. In the present study, we evaluated the effects of gentle treadmill walking on subchondral bone and cartilage changes in an experimental rat model of destabilized medial meniscus (DMM).

METHOD

Twelve-week-old Wistar rats underwent DMM surgery in their right knee and sham surgery in their left knee and were assigned to either the sedentary group or walking group (n = 42/group). Animals in the walking group were subjected to treadmill exercise 2 days after surgery, which included walking for 12 m/min, 30 min/day, 5 days/week for 1, 2, and 4 week(s). Subchondral bone and cartilage changes were evaluated by micro-CT analysis, histological analysis, and biomechanical analysis.

RESULTS

Treadmill walking had a tendency to suppress SBC growth, which was confirmed by micro-CT (P = 0.06) and positive staining for tartrate-resistant acid phosphatase (TRAP) activity for the osteoclast number per bone surface (P = 0.09) 4 weeks after surgery. These changes coincide with the prevention of cartilage degeneration as evaluated by the Osteoarthritis Research Society International (OARSI) score (P < 0.05) and biomechanically softening (P < 0.05). Furthermore, treadmill walking could suppressed increasing osteocyte deaths (P < 0.01), which was positively correlated with the OARSI score (r = 0.77; P < 0.01).

CONCLUSION

These results indicate biomechanical and biological links exist between cartilage and subchondral bone; preventive effects of treadmill walking on subchondral bone deterioration might be partly explained by the chondroprotective effects.

Effect of LSKL peptide on thrombospondin 1-mediated transforming growth factor β signal activation and liver regeneration after hepatectomy in an experimental model

Background

A strategy for accelerating liver regeneration after hepatectomy would offer great benefits in preventing postoperative liver failure and improving surgical outcomes. Transforming growth factor (TGF) β is a potent inhibitor of hepatocyte proliferation. Recently, thrombospondin (TSP) 1 has been identified as a negative regulator of liver regeneration by activation of local TGF-β signals. This study aimed to clarify whether the LSKL (leucine–serine–lysine–leucine) peptide, which inhibits TSP-1-mediated TGF-β activation, promotes liver regeneration after hepatectomy in mice.

Methods

Mice were operated on with a 70 per cent hepatectomy or sham procedure. Operated mice received either LSKL peptide or normal saline intraperitoneally at abdominal closure and 6 h after hepatectomy. Perioperative plasma TSP-1 levels were measured by enzyme-linked immunosorbent assay in patients undergoing hepatectomy.

Results

Administration of LSKL peptide attenuated Smad2 phosphorylation at 6 h. S-phase entry of hepatocytes was accelerated at 24 and 48 h by LSKL peptide, which resulted in faster recovery of the residual liver and bodyweight. Haematoxylin and eosin tissue staining and blood biochemical examinations revealed no significant adverse effects following the two LSKL peptide administrations. In the clinical setting, plasma TSP-1 levels were lowest on the first day after hepatectomy. However, plasma TSP-1 levels at this stage were significantly higher in patients with subsequent liver dysfunction compared with levels in those without liver dysfunction following hepatectomy.

Conclusion

Only two doses of LSKL peptide during the early period after hepatectomy can promote liver regeneration. The transient inhibition of TSP-1/TGF-β signal activation using LSKL peptide soon after hepatectomy may be a promising strategy to promote subsequent liver regeneration.

Destabilization of the medial meniscus leads to subchondral bone defects and site-specific cartilage degeneration in an experimental rat model

OBJECTIVE

This study aimed to investigate subchondral bone changes using micro-computed tomography (micro-CT) and regional differences in articular cartilage degeneration, focusing on changes of cartilage covered by menisci, in the early phase using a destabilization of the medial meniscus (DMM) model.

METHOD

The DMM model was created as an experimental rat osteoarthritis (OA) model (12 weeks old; n = 24). At 1, 2, and 4 weeks after surgery, the rats were sacrificed, and knee joints were scanned using a Micro-CT system. Histological sections of the medial tibial plateau, which was divided into inner, middle, and outer regions, were prepared and scored using the modified OARSI scoring system. The cartilage thickness was also calculated, and matrix metalloproteinase 13 (MMP13), Col2-3/4c, and vascular endothelial growth factor (VEGF) expression was assessed immunohistochemically.

RESULTS

Subchondral bone defects were observed in the middle region, in which the cartilage thickness decreased over time after surgery, and these defects were filled with MMP13- and VEGF-expressing fibrous tissue. The OARSI score increased over time in the middle region, and the score was significantly higher in the middle region than in the inner and outer regions at 1, 2, and 4 weeks after surgery. Col2-3/4c and MMP13 expression was observed primarily in the meniscus-covered outer region, in which the cartilage thickness increased over time.

CONCLUSION

Loss of meniscal function caused cartilage degeneration and subchondral bone defects in the early phase site-specifically in the middle region. Furthermore, our results might indicate cartilage covered by menisci is easily degraded resulting in osmotic swelling of the cartilage in early OA.

Statins inhibit tumor progression via an enhancer of zeste homolog 2-mediated epigenetic alteration in colorectal cancer

While statin intake has been proven to reduce the risk of colorectal cancer (CRC), the mechanism of antitumor effects and clinical significance in survival benefits remain unclear. Statin-induced antiproliferative effects and its underlying mechanism were examined using six CRC cell lines. Statins except pravastatin showed antiproliferative effects (simvastatin ≥ fluvastatin > atorvastatin) even though both of simvastatin and pravastatin could activate mevalonate pathways, suggesting the statin-mediated antiproliferative effects depended on non-mevalonate pathway. Indeed, statin induced p27(KIP1) expression by downregulation of histone methyltransferase enhancer of zeste homolog 2 (EZH2), which acts as an epigenetic gene silencer. Additionally, the use of simvastatin plus classII histone deacetylase (HDAC) inhibitor (MC1568) induced further overexpression of p27(KIP1) by inhibiting HDAC5 induction originated from downregulated EZH2 in CRC cells and synergistically led to considerable antiproliferative effects. In the clinical setting, Statin intake (except pravastatin) displayed the downregulated EZH2 expression and inversely upregulated p27(KIP1) expression in the resected CRC by immunohistochemical staining and resulted in the significantly better prognoses both in overall survival (p = 0.02) and disease free survival (p < 0.01) compared to patients without statin intake. Statins may inhibit tumor progression via an EZH2-mediated epigenetic alteration, which results in survival benefits after resected CRC. Furthermore, statin plus classII HDAC inhibitor could be a novel anticancer therapy by their synergistic effects in CRC.

CD44s signals the acquisition of the mesenchymal phenotype required for anchorage-independent cell survival in hepatocellular carcinoma

Background:

Circulating tumour cells (CTCs) have an important role in metastatic processes, but details of their basic characteristics remain elusive. We hypothesised that CD44-expressing CTCs show a mesenchymal phenotype and high potential for survival in hepatocellular carcinoma (HCC).

Methods:

Circulating CD44⁺CD90⁺ cells, previously shown to be tumour-initiating cells, were sorted from human blood and their genetic characteristics were compared with those of tumour cells from primary tissues. The mechanism underlying the high survival potential of CD44-expressing cells in the circulatory system was investigated in vitro.

Results:

CD44⁺CD90⁺ cells in the blood acquired epithelial–mesenchymal transition, and CD44 expression remarkably increased from the tissue to the blood. In Li7 and HLE cells, the CD44^high population showed higher anoikis resistance and sphere-forming ability than did the CD44^low population. This difference was found to be attributed to the upregulation of Twist1 and Akt signal in the CD44^high population. Twist1 knockdown showed remarkable reduction in anoikis resistance, sphere formation, and Akt signal in HLE cells. In addition, mesenchymal markers and CD44s expression were downregulated in the Twist1 knockdown.

Conclusions:

CD44s symbolises the acquisition of a mesenchymal phenotype regulating anchorage-independent capacity. CD44s-expressing tumour cells in peripheral blood are clinically important therapeutic targets in HCC.

Expression of BAFF and BAFF-R in the synovial tissue of patients with rheumatoid arthritis

OBJECTIVE

The elevated expression of B-cell-activating factor belonging to the TNF family (BAFF) is associated with systemic autoimmune disease, including rheumatoid arthritis (RA). The present study was undertaken to determine the distribution of BAFF and its receptor BAFF-R in the cells residing in the rheumatoid synovium.

METHODS

The expression of BAFF and BAFF-R in synovial tissues obtained from 12 RA patients was examined by immunohistochemistry and flow cytometry. The mRNA expression of these molecules was determined by reverse transcriptase polymerase chain reaction (RT-PCR). Soluble BAFF levels were measured with an enzyme-linked immunosorbent assay (ELISA). Fibroblast-like synoviocytes (FLS) purified from the RA (RA-FLS) were co-cultured with peripheral B cells. The degree of apoptosis in the B cells was measured to assess the effects on the viability of the B cells.

RESULTS

The RA synovium showed focal or diffuse infiltration of mononuclear cells (MNCs), and one specimen showed germinal centre (GC)-like structures. Synovial sublining cells, but not lining cells, expressed BAFF. These sublining cells were negative for BAFF-R. BAFF and BAFF-R were expressed in B and T cells extracted from the RA synovium. Notably, RA-FLS spontaneously expressed cytoplasmic BAFF after 4-6 passages; however, they did not express BAFF or BAFF-R on their cell surface. RA-FLS could support the survival of B cells by preventing their apoptosis, but its effect on B cells might not be BAFF dependent.

CONCLUSIONS

BAFF and BAFF-R are widely expressed in the RA synovium. The cells residing in the RA synovium might affect each other through BAFF.

Maturation-dependent change and regional variations in acoustic stiffness of rabbit articular cartilage: an examination of the superficial collagen-rich zone of cartilage

OBJECTIVE

The purpose of the study was to investigate maturation-dependent changes of acoustic (ultrasound) stiffness and other ultrasound features of articular cartilage in healthy rabbit knees.

METHODS

Five groups of rabbits of various ages (3 weeks, 8 weeks, 6 months, 1 year, 2.5 years) consisting of five rabbits per group were examined. Signal intensity (index of stiffness), signal duration (index of surface irregularity) and interval between signals (index of thickness) of the ultrasound reflection from articular cartilage were examined at four sites: posterior lateral femoral condyle, posterior medial femoral condyle, lateral tibial plateau, and medial tibial plateau. The sites were observed macroscopically and microscopically with a light microscope and a polarized light microscope.

RESULTS

At the lateral and medial condyles and the lateral tibial plateau, signal intensity was least in 3-week-old specimens. The intensity increased until 6 months or 1 year of age. At these sites, the signal durations and intervals between signals were least at the ages of 6 months or 1 year. At the medial tibial plateau, the intensity was the least at 2.5 years of age and the interval between signals was least at 3 weeks of age; there was no effect of age on signal duration. Cartilage surfaces of all specimens were smooth and no degenerative changes were macroscopically or microscopically evident. The surface brightness of cartilage under the polarized light microscope was consistent with signal intensity values.

CONCLUSIONS

The response of articular cartilage to ultrasound was maturation-dependent. Acoustic properties differed from mechanical stiffness properties, which were determined using indentation. Ultrasound may detect properties of the surface collagen of the articular cartilage.

The effects of subminimal inhibitory concentrations of beta-lactam antibiotics against Clostridium perfringens

The effects of subminimal inhibitory concentrations (sub-MIC) of four beta-lactam antibiotics [penicillin-G (PCG), ampicillin (AMP), cephaloridine (CER), cephalothin (CET)] were tested against Clostridium perfringens type A PB6K, after determining the minimum inhibitory concentrations (MIC) of 29 different Clostridium strains. The majority of the strains were sensitive to all beta-lactam antibiotics. Morphological changes, such as filamentous development and lysis, occurred at concentrations considerably lower than the MIC of CER and CET in C. perfringens. Clear cooperation of AMP and CER with rabbit polymorphonuclear leucocytes (PMNL) against C. perfringens was observed. The filamentous bacteria produced as a result of exposure to sub-MIC of each antibiotic, were phagocytosed easily. The ratios between the drug concentrations (microg/ml) at which the morphological changes began to occur, the minimum antibiotic concentrations (MAC), and the MIC values (microg/ml), were calculated. A large ratio indicated a wide range of effective concentrations below the MIC value for the antibiotics.

Gene analysis of Vibrio cholerae NAGV14 pilus and its distribution

Adhesive pilus of Vibrio cholerae 034, strain NAGV14, was genetically analyzed. The deduced amino acid (aa) sequence of the major pilin structural gene (VcfA) was 67% homologous to the MshA pilin in the N-terminal region, but no homology was found in the C-terminal region which contained the antigenic epitopes. Upstream and downstream flanking regions examined were highly homologous to mshB and mshC of the MSHA (mannose-sensitive hemagglutinin) gene locus. A short leader sequence and a pair of cysteines near the C-terminus which are the characteristics of type 4a pilus family were found. The major pilin structural gene of NAGV14 was compared to that of a strain V10 producing non-adhesive pili. The deduced aa sequences showed 60% homology, and the distance between two cysteines in the C-terminal region was different. A total of 177 V. cholerae strains were investigated for the presence of a type 4 pilus gene locus by PCR, and 95% were positive. The major pilin gene of NAGV14 was detected in 4 of 93 V. cholerae non-O1, non-0139 strains tested, but none of the V. cholerae O1 and O139 (72 and 12 strains, respectively). Our result suggested that a type 4 pilus gene locus similar to the MSHA gene locus is widely distributed among V. cholerae strains. We proposed naming this type 4 pilus gene locus the VCF (for V. cholerae flexible pili) gene locus.

[Causes of dementia and bed-ridden state in elderly victims of road traffic accidents in Japan]

BACKGROUND

In Japan, autopsies are seldom performed for the victims of road traffic accidents (RTA). Thus, when an elderly RTA victim dies after long-term hospitalization, the actual cause of death is hard to determine.

SUBJECTS

Eight hundred eleven road traffic victims (69 +/- 16 years, M/F = 592/219) for whom insurance companies required us to judge the medical causal relation between the accident and the death from the view point of clinical forensic medicine.

METHODS

We discussed and reevaluated the cause of death and decided the cause and effect relation based on medical information.

RESULTS

The number of subjects was equivalent to 8.4% of the yearly deaths by RTA in the investigated area, 19.3% of the aged death by RTA. An autopsy was performed only for 5%, ISS was 17.0 +/- 11.5; 94% were hospitalized; 62% continued to be unconscious, involving dementia (32%), persistent vegetative state (17%), coma or semi-coma (13%). Of the cases investigated, 89% died after becoming bedridden, which in 87% of cases was due to the RTA. The odds ratios of a bedridden state for head AIS > = 3, lower limbs AIS > = 2, lower limbs AIS > = 3, spinal AIS > = 3, chest AIS > = 2 were 3.1, 3.2, 7.2, 2.5, 1.8, respectively. The odds ratios of dementia for head AIS > = 3, head AIS > = 4, chest AIS > = 4 were 29.2, 35.9, 1.2, respectively. Patients with head injuries were more likely to be bedridden and senile, and patients with leg fractures tended to be bedridden, particular in the aged. When elderly traffic victims became bedridden or senile, most of them, 399 bedridden victims and 53 non-bedridden victims, died within 242 +/- 283 days, and 356 +/- 284 days from the RTA, respectively. The cause of death could be classified into five categories; pneumonia, other infection, malnutrition and/or dehydration, malnutrition and/or dehydration with pneumonia, malnutrition and/or dehydration with other infection. Traffic deaths were recorded on 31% of death certificates, but were 77% by our reevaluation (p < 0.00001), because the cause-of-death can be difficult to determine in elderly traffic victims. Logistic regression was used to calculate the risk of dementia caused by bone fractures after adjusting for age and gender. The risk of dementia due to bone fractures was influenced by the number of the long fractured bones, a high age group, a lower ADL, and a past history of dementia. Thus, we speculate that traumatic dementia based on bone fractures may occur.

[Assessment of hydroxylated metabolites of polychlorinated biphenyls and polychlorinated dibenzofurans as potential estrogens by yeast two-hybrid system]

The estrogenic activities of several hydroxylated metabolites of PCBs and PCDFs were investigated by yeast two-hybrid assay based on the ligand-dependent interaction of estrogen receptor with coactivator. For the hydroxylated PCBs, the order of estrogenic potency was 4-OH-2',4',6'-triCB > 4-OH-4'-monoCB, 4-OH-biphenyl. These compounds were evaluated as 10(3) to 10(4) less potent than 17 beta-estradiol based on the concentrations of test compounds showing 10% activity of 10(-7) M 17 beta-estradiol. 2-OH-3',4,4'-triCB, 4-OH-2',3,4'-triCB and 3-OH-/4-OH-2,2',5,5'-tetraCB, the metabolites of 2,2',5,5'-tetraCB were inactive as estrogens at the highest concentrations used in this study (10(-5) M). Also 4-OH-3,3',4',5-tetraCB, the metabolite of 3,3',4,4'-tetraCB was inactive as estrogen, indicating that this hydroxylated metabolite did not take part in the estrogenic activity of 3,3',4,4'-tetraCB. OH group at 4-position of biphenyl was necessary for the expression of estrogenicity, but one or two chloro-substitution adjacent to OH group inhibited the activity. For the hydroxylated PCDFs, 8-OH-2-monoCDF, 7-OH-3,4-diCDF, 8-OH-3,4-diCDF, 8-OH-3,4,6-triCDF and 3,8-(OH)2-2-monoCDF exhibited estrogenic activity. The estrogenic activity of 3,8-(OH)2-2-monoCDF was comparable to those of 4-OH-2',4',6'-triCB and 4-nonylphenol (mixture of compounds with branched sidechain). The order of activity was 3,8-(OH)2-monoCDF > 8-OH-3,4-diCDF, 7-OH-3,4-diCDF > 8-OH-2-monoCDF, 8-OH-3,4,6-triCDF. These compounds were evaluated as 2.5 x 10(3) to 3 x 10(4) less potent than 17 beta-estradiol. On the other hand, no estrogenic activity was observed for 2-OH-dibenzofuran, 3-OH-2,8-diCDF, 6-OH-3,4-diCDF and 9-OH-3,4-diCDF at concentrations as high as 10(-4) M. Substitution of OH group at 2(8)- or 3(7)-position of dibenzofuran and no chloro-substitution adjacent to OH group was required for the estrogenic activity.

[The changes of PCBs and PCDFs as well as symptoms in Yusho patients for 30 years]

Two mass-food poisonings called Yusho and Yucheng occurred in Western Japan and Taiwan in 1968 and 1979, respectively. Blood samples from 5 Yusho patients and 3 Yucheng patients were collected several times from 1982 to 1998 and from 1980 to 1995, respectively, and analyzed for PCB and PCDF congeners. Fat base concentrations of 2,3,4,7,8-penta-CDF in the Yusho patients, which were responsible for about 70% of the dioxin toxicity, are estimated to be decreased from 60 ppb in 1969 to 0.8 ppb in 1997 with the median half-life of 2.9 years in the first 15 years after the onset and 7.7 years in the next stage of 15 years. Fat base concentrations of total PCBs in the blood of Yusho patients are estimated to be decreased from 75 ppm just after the onset to 2.3 ppm after passage of 30 years. Typical Yusho symptoms of acneiform eruption, dermal pigmentation and increased eye discharge were very gradually recovered with lapse of ten years. However, enzyme and/or hormone mediated sign of high serum triglyceride, high serum thyroxin, immunoglobulin disorder and others are persistently maintained for 30 years.

Pesticide poisoning initially suspected as a natural death

A pesticide poisoning victim suspected initially as having died a natural death was autopsied. The victim was a 47-year-old male. Macroscopically, signs of acute death and, in particular, general erosion in the mucosa of the airways and esophagus were observed. In the gastric contents, which had a pungent smell and a greenish-brown color, 5.00 g/L of propanil, 1.27 g/L of carbaryl, 0.38 g/L of ethylbenzene, and 0.32 g/L of xylene were detected. In the blood (serum), 21.6 mg/L of propanil, 8.1 mg/L of carbaryl, 1.7 mg/L of ethylbenzene, and 4.0 mg/L of xylene were identified. Postmortem methemoglobinemia (45%) was recognized. The cause of death was considered to have been pesticide poisoning; propanil was probably most responsible for his death. The police considered the case to be "death with illness as the suspected cause." By performing an autopsy, however, we were able to clarify that the cause of death was pesticide poisoning.

Haemophilus influenzae infection and Guillain-Barré syndrome

It has been reported recently that Haemophilus influenzae can elicit an axonal form of Guillain-Barré syndrome. To investigate the incidence and features of H. influenzae-related Guillain-Barré syndrome, anti-H. influenzae antibody titres were measured by enzyme-linked immunosorbent assay (ELISA) in 46 consecutive Japanese patients with Guillain-Barré syndrome, 49 normal controls, 24 patients with multiple sclerosis and 27 patients with amyotrophic lateral sclerosis (ALS). Whole bacteria of non-encapsulated (non-typable) H. influenzae isolated from one of the Guillain-Barré syndrome patients was the antigen used. Elevated anti-H. influenzae antibodies for two or three classes of IgG, IgM and IgA were found in six (13%) Guillain-Barré syndrome patients, but not in the normal controls and patients with multiple sclerosis or ALS. The incidence was significantly higher in patients with Guillain-Barré syndrome than in the normal controls (P = 0.01) and patients with multiple sclerosis or ALS (P = 0.009). Western blot analysis confirmed that the H. influenzae-positive patients' IgG recognized the lipopolysaccharides of H. influenzae. Guillain-Barré syndrome patients with anti-H. influenzae antibodies showed relatively uniform clinical and laboratory features: prodromal respiratory infection, less frequent cranial and sensory nerve involvement, pure motor axonal degeneration on electrophysiology, and positivity for IgG anti-GM1 antibodies. Although the features were similar to those in Guillain-Barré syndrome patients infected by Campylobacter jejuni, the recoveries seemed to be better in patients with H. influenzae-related Guillain-Barré syndrome. It is concluded that a form of Guillain-Barré syndrome occurs after respiratory infection by H. influenzae in the Japanese population. A particular strain of non-typable H. influenzae has a ganglioside GM1-like structure and elicits axonal Guillain-Barré syndrome similar to C. jejuni-related Guillain-Barré syndrome.

Characterization of an early decline in baseline plasma glucose concentration after acute insulin elevation during euglycemic hyperinsulinemic clamp in patients with type 2 diabetes mellitus

To investigate the contribution of the liver to whole-body insulin resistance in patients with type 2 diabetes mellitus, we analyzed the early decline (slope "a") in the baseline plasma glucose level following acute hyperinsulinemia in the initial phase of a euglycemic hyperinsulinemic clamp study, rather than using an isotope-dilution method. Slope "a" was comparable among groups of diabetic and non-diabetic subjects, and did not correlate well with glucose infusion rate (GIR), an index of peripheral (primarily skeletal muscle) insulin resistance. In contrast, slope "a" was significantly lower in obese (BMI > 25) type 2 diabetic patients compared with their non-obese counterparts, consistent with the general belief that obesity is a condition of insulin resistance in liver as well as in peripheral tissues. A subset of six insulin-resistant (nearly zero GIR) type 2 diabetic patients (pubertal adolescents) demonstrated a markedly blunted slope "a". Their insulin resistance (GIR) substantially recovered concomitant with an increase in slope "a" after pretreatment with somatostatin analogue in two cases studied, suggesting possible suppression of hepatic glucose production through lowering of plasma glucagon concentrations. Furthermore, slope "a" correlated significantly (r = -0.480, p<0.0001) with HOMA index (FPG x FIRI), the latter being recently regarded as an index of hepatic insulin resistance. These data showed that slope "a" obtained from euglycemic hyperinsulinemic clamp may be a clinically useful index of hepatic insulin resistance rather than an index of peripheral insulin resistance.

[Infections with drug resistant bacteria and their treatment methods--PRSP infections]

S. pneumoniae is one of the most important pathogens in respiratory tract infections and systemic infections. The frequencies of isolating Penicillin-resistant Streptococcus pneumoniae(PRSP) has been increasing recently. The therapeutic strategy is becoming difficult. Ampicillin and amoxicillin are the choices of drugs to treat respiratory infections with intermediate strains. Panipenem may be the first choice of treatment for systemic infections. Administration of vancomycin should also be considered. Judicious use of antimicrobials is necessary to avoid the spread of multi-resistant strains. In some cases physical therapy would be recommended.

[The incidences of virulence genes in Escherichia coli strains from sporadic diarrheal children]

To investigate the incidence of diarrheagenic Escherichia coli among E. coli strains screened by commercially available O-antigen antisera, we used PCR to isolate 8 virulence genes (eae, bfpA, IpaH, LT, ST, VT1, VT2, and aggR) in 184 E. coli strains sampled from sporadic diarrheal children in our district. eae and bfpA are the localized adherence factor genes of enteropathogenic E. coli (EPEC). IpaH is the invasion antigen gene of enteroinvasive E. coli (EIEC), LT and ST are the toxin genes of enterotoxigenic E. coli (ETEC), VT1 and VT2 are the toxin genes of enterohemorrhagic E. coli (EHEC), and aggR is the adherence factor gene of enteroaggregative E. coli (EAggEC). The results were as follows: eae, 7 (3.8%); bfpA, 0 (0%); IpaH, 0 (0%); LT, 0 (0%); ST, 2 (1.1%); VT, 5 (2.7%); aggR, 8 (4.3%). Seven isolates with eae did not have bfpA, and did not show a localized adherence to HeLa cells. Seven of the 8 isolates with aggR showed aggregative adherence to HeLa cells, while their O-serotypes of them were O111:H21 or O111:HUT. Because of the low incidence of the virulence gene, the commercially available O-antigen antisera was not expected to be useful for the screening of diarrheagenic E. coli, except for EHEC and EAggEC. EAggEC may be important as a pathogen of sporadic diarrhea of children as well as EHEC.

[Clinical analysis of patients with bacterial meningitis in childhood and reevaluation of rapid antigen detection methods]

Twenty-eight cases of bacterial meningitis during the recent ten years were analyzed retrospectively, and the following results were obtained. 1. Pathogens were as follows; H. influenzae 13 (46.4%), S. pneumoniae 8 (28.6%), S. agalactiae 4 (14.3%), E. coli 2 (7.1%), and L. monocytogenes 1 case (3.6%). 2. Twelve out of the thirteen H. influenzae cases were caused by serotype b (Hib), and 2 strains were beta-lactamase producer. Fifty percent of the S. pneumoniae cases were caused by penicillin-resistant strains. And all these resistant strains belonged to serotype 19 or 23. 3. Underlying diseases related to the onset of meningitis were found in 46% of the cases, and these consisted of CNS shunt operated 5, asplenia or polysplenia 2, Mondini's anomaly 1, sacral dermal sinus 1, and neonate 4 cases. 4. Prognosis of these cases were three deaths, four with neurologic sequelae, and twenty-one complete recoveries. 5. On admission, 85% (17/20) of the cases were diagnosed correctly by the rapid antigen detection. Sensitivity and specificity of the rapid antigen detection by using latex particle agglutination is 90% and 100% in the Hib cases, and 83% and 100% in the S. pneumoniae cases respectively. Moreover, the bacteriologically unknown 2 cases caused by parenteral partial treatment were also diagnosed by the detection of antigen in concentrated urine.

Molecular epidemiological study of Haemophilus influenzae serotype b strains obtained from children with meningitis in Japan

We report an epidemiological study of 30 Haemophilus influenzae serotype b (Hib) strains derived from the cerebrospinal fluid of children with meningitis. The Hib strains were biotyped, tested for beta-lactamase production, and genotyped by long PCR-ribotyping, random amplified polymorphic DNA (RAPD) analysis, and genomic DNA restriction fragment length polymorphism (RFLP) analysis by pulsed-field gel electrophoresis (PFGE). The phenotypic study characterized 22 of the strains (73%) as biotype I. A genotypic study using long PCR-ribotyping with HaeIII restriction digestion showed no polymorphisms among these 30 Hib strains, but RAPD analysis with two sets of primers demonstrated two distinctive subtypes: one typical of the strains of biotype group II and the second characteristic of the strains of biotype groups I and IV. Each RAPD group was subtyped into several genotypic groups by PFGE-RFLP with SmaI digestion. The genotyping of clinically isolated Hib strains may help to elucidate transmission routes in community infections, endemicity, and the reasons for vaccine failure.

Detection of influenza virus RNA by reverse transcription-PCR and proinflammatory cytokines in influenza-virus-associated encephalopathy

Eleven children with acute encephalopathy associated with an influenza virus infection were treated during the 1997-1998 influenza season. Reverse transcription-polymerase chain reaction (RT-PCR) assay was used to detect the viral genome in peripheral blood and cerebrospinal fluid (CSF) samples. The results were compared with those of control influenza patients without neurological complications. Viral RNA was detected only in the peripheral blood mononuclear cells of one patient with influenza-virus-associated encephalopathy (1 of 9; 11%) and in the CSF of another patient (1 of 11;9%). RT-PCR was negative in the blood of all the controls, but the percentage of RT-PCR-positive samples in the two groups was not significantly different. Cytokines and soluble cytokine receptors in plasma and CSF were then quantified using an enzyme-linked immunosorbent assay. The CSF concentrations of soluble tumor necrosis factor receptor-1 were elevated in two patients and interleukin-6 (IL-6) was elevated in one patient with influenza-virus-associated encephalopathy. On the other hand, the plasma concentrations of IL-6 were elevated in four of nine patients. The number of encephalopathy patients who had elevated plasma concentrations of IL-6 100 pg/ml was significantly higher than that of controls (P= .01). In conclusion, the infrequent detection of the viral genome in the CSF and blood showed that direct invasion of the virus into the central nervous system was an uncommon event. Proinflammatory cytokines and soluble cytokine receptors may mediate the disease. The high plasma concentration of IL-6 could be an indicator of the progression to encephalopathy.

Simultaneous detection of multiple STR loci on sex chromosomes for forensic testing of sex and identity

The forensic usefulness of X and Y chromosomal STR loci has recently been demonstrated. One quadruplex-PCR, using 2 X- and 2 Y-STRs (STRX1/HPRTB and DYS390/ DYS393), and 2 duplex-PCRs, each using an X- and a Y-STR (ARA/DYS390 and ARA/DYS393), and detection of PCR products by using an automated DNA sequencer are reported herein. This approach allows us to determine not only the sex of the donor of a sample, but also the X- and/or Y-STR genotypes of the sample. A male biological specimen yields 4 amplified products in quadruplex-PCR and 2 amplified fragments in duplex-PCRs, whereas a female biological specimen yields only 2 amplified fragments of X-STR in quadruplex-PCR and one fragment, also of X-STR, in duplex-PCRs. Our study thus provides useful information for many activities in forensic practice, such as identity testing, paternity testing, especially of deficiency cases, compilation of population data, and sex determination of a biological sample from a single PCR.

Segmental square spinal instrumentation for posterior lumbar spinal fixation

The purpose of this study is to evaluate the clinical results of operations using a new spinal instrumentation for posterior fixation, called segmental square spinal (3-S) instrumentation. The 3-S instrument consists of two pairs of hooks to clasp the interarticular portion of the lamina bilaterally, two horizontal bars to connect the hooks on the right and left, and rods to connect the hooks side by side on the top and bottom. Twenty-seven patients who had degenerative lumbar disorders underwent operations with the 3-S instrument. Rigid fixation was obtained in all cases immediately after the operation. Bone union rates were 91% (21/23) with posterolateral fusion. The 3-S instrument seems to be suitable for spinal disorders in which anterior spinal fusion is not necessary, especially for degenerative spinal disorders.

[Comparative study on metabolism of three tetrachlorobiphenyls with animal liver microsomes]

In vitro metabolism of 3,5,3',4'-, 3,5,3',5'- and 2,4,3',4'-tetrachlorobiphenyls (TCBs) was studied using liver microsomes from rats, guinea pigs and hamsters. 3,5,3',4'-TCB was metabolized to 4-hydroxy-3,5,3',4'-TCB with liver microsomes of 3-methyl-cholanthrene (MC)- and 3,4,5,3',4'-pentachlorobiphenyl (PenCB)-treated rats but not of phenobarbital (PB)-treated ones. This result suggests that a MC-inducible cytochrome P450 isoform, probably CYP1A1, is more important in the in vitro metabolism of 3,5,3',4'-TCB in rat liver and that the isoform attacks the 3,5-dichloro-substituted phenyl ring more predominantly than 3,4-dichloro-substituted one. In 3,5,3',5'-TCB metabolism, liver microsomes from MC- and 3,4,5,3',4'-PenCB-treated hamsters formed 4-hydroxy-3,5,3',5'-TCB to a similar extent to rats reported previously. Guinea pig liver microsomes formed no metabolite. In 2,4,3',4'-TCB metabolism, PB accelerated 3-, 5- and 4-hydroxylations in guinea pigs and also 3- and 5-hydroxylations in hamsters, suggesting the involvement of a PB-inducible P450 isoform, presumably P450GP-1 and P450HPB-1, respectively. On the other hands, MC- and 3,4,5,3',4'-PenCB-treatment resulted in the marked increase of 4-hydroxylation in hamsters, but in the suppression of 4-hydroxylation in guinea pigs. From these results, it is suggested that the hydroxylation of coplanar TCBs such as 3,5,3',4'- and 3,5,3',5'-TCB is catalyzed by a MC-inducible P450 in rats and hamsters, whereas non-coplanar TCBs such as 2,4,3',4'-TCB which possesses both PB- and MC-like inducing ability of liver enzymes are metabolized by one or more kinds of P450 isoform induced by PB and MC.

Induction of sister chromatid exchanges in cultured human lymphocytes with methylsulphonyl PCB congeners

Methylsulphonyl polychlorinated biphenyls (MSF-PCBs) have already contaminated at relatively high concentration in the lungs and blood of Yusho patients and healthy Japanese people. Therefore, we should give due attention to their biological and toxicological effects to man. In this study, in order to evaluate S-dependent genotoxicity of five MSF-PCB congeners, namely, 3-MSF-4,5,3',4'-tetrachlorobiphenyl (TCB), 3-MSF-4,5,2',3'-TCB, 3-MSF-2,5,2',4',5'-pentachlorobiphenyl (PenCB), 4-MSF-2,5,2',3',4'-PenCB and 4-MSF-2,5,2',3',5',6'-hexachlorobiphenyl (HCB), we have examined their effects on the induction of sister chromatid exchanges (SCEs), which has been frequently used to estimate the dose of S-dependent clastogens, in cultured human lymphocytes in the absence or presence of 2,3,4,7,8-pentachlorodibenzofuran (PenCDF), 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) or 3,4,5,3',4'-pentachlorobiphenyl (Co-PenCB) and the following results were obtained. 1) 4 x 10(-5)M, 7,8-benzoflavone (ANF) and two of the five MSF-PCB congeners, namely, 3-MSF-2,5,2',4',5'- and 4-MSF-2,5,2',3',4'-PenCB at respective doses of 5.2 and 5.8 ppm, which were about 35,000 times higher than the concentrations in the lungs and adipose tissue of healthy Japanese people, significantly enhanced the frequency of SCEs. 2) In the simultaneous treatment of one of the five MSF-PCB congeners and PenCDF (3.9 ppb), TCDD (1.5 ppb) or Co-PenCB (8.8 ppb), the combination of 3-MSF-4,5,3',4'-TCB (6.8 ppb) or 4-MSF-2,5,2',3',5',6'-HCB and one of the three highly toxic chemicals significantly promoted the formation of SCEs. We have already studied whether these MSF-PCBs are non-S-dependent genotoxic compounds or not and have obtained the results that they seemed not to be or very weak ones. Therefore, based on the results of this and our former studies, the five MSF-PCB congeners examined are considered rather potent S-dependent genotoxic chemicals than non-S-dependent ones.

Haemophilus influenzae has a GM1 ganglioside-like structure and elicits Guillain-Barré syndrome

The authors report a patient with an axonal Guillain-Barré syndrome (acute motor axonal neuropathy) associated with anti-GM1 antibody after Haemophilus influenzae infection. The result of ELISA inhibition studies and cytochemical staining with cholera toxin suggest the presence of a GM1-like structure on the surface of H. influenzae isolated from the patient. A particular strain of H. influenzae may have a GM1-like structure and may elicit an axonal Guillain-Barré syndrome.

A comparative study of chemonucleolysis with recombinant human cathepsin L and chymopapain. A radiologic, histologic, and immunohistochemical assessment

STUDY DESIGN

Investigation of the effects of recombinant human cathepsin L on intervertebral discs and comparison with the effects of chymopapain.

OBJECTIVE

To evaluate the effects of cathepsin L on intervertebral discs as an agent for chemonucleolysis.

SUMMARY BACKGROUND DATA

Cathepsin L is a typical cysteine proteinase that belongs to the papain superfamily. It plays a major role in intracellular proteolysis and is not believed to induce anaphylactic reactions.

METHODS

In vivo: Rabbit intervertebral discs were injected with recombinant human cathepsin L, its buffer solution, and chymopapain. After 1, 4, and 16 weeks the animals were killed, and radiologic and histologic examinations were performed. In vitro: The enzymatic actions of recombinant human cathepsin L and chymopapain on human intervertebral disc proteoglycans were examined immunohistochemically using antiproteoglycan antibodies.

RESULTS

In rabbit models, roentgenography showed that disc spaces treated with cathepsin L and chymopapain had become narrower 1 week after injection. Histologically, loss of safranin-O staining was observed in the anulus fibrosus of discs treated with cathepsin L. After 16 weeks, nucleus pulposus had regenerated with chondrocyte-like cells, and the safranin-O staining characteristics of the matrix also had recovered. In an immunohistochemical study, all components of the proteoglycan stained weakly after chymopapain digestion. After cathepsin L digestion, unsulfated chondroitin and core protein staining was weaker, but the chondroitin 6-sulfate staining was unaffected.

CONCLUSIONS

Cathepsin L seems to be an effective agent for chemonucleolysis. Its enzymatic action on proteoglycan appears to be different from that of chymopapain.

Comparative study of MR myelography and conventional myelography in the diagnosis of lumbar spinal diseases

The purpose of this study was to investigate the usefulness of magnetic resonance (MR) myelography by comparing it with conventional myelography. MR myelography was performed on 40 patients (24 men and 16 women; mean age, 44 years) with lumbar spinal diseases. MR myelography was imaged three-dimensionally by fast spin-echo technique with fat suppression and maximum intensity projection. We assessed both the ability to provide the images of nerve root sheaths and the similarity of the findings to conventional myelography. Satisfactory images of nerve root sheaths in the lumbar region were provided almost equally by MR and conventional myelography. The images obtained by MR myelography were similar in quality to those obtained by conventional myelography. When combined with some other conventional MR imaging techniques, this diagnostic technique of imaging lumbar spinal diseases is further enhanced.

Liver and kidney function in Japanese patients with maturity-onset diabetes of the young

OBJECTIVE

Heterozygous mutations in the transcription factors hepatocyte nuclear factor (HNF)-1 alpha, HNF-1 beta, and HNF-4 alpha are associated with maturity-onset diabetes of the young (MODY) and are believed to cause this form of diabetes by impairing pancreatic beta-cell function. The HNFs also play a central role in the tissue-specific regulation of gene expression in liver and kidney, suggesting that patients with MODY due to a mutation in HNF-1 alpha, HNF-1 beta, or HNF-4 alpha may exhibit abnormal liver or kidney function. Here, we have examined liver and kidney function in a series of Japanese patients with HNF-4 alpha/MODY1, HNF-1 alpha/MODY3, and HNF-1 beta/MODY5 diabetes.

RESEARCH DESIGN AND METHODS

Clinical and biochemical data were obtained from Japanese subjects with HNF-1 alpha, HNF-1 beta, and HNF-4 alpha diabetes. The clinical data included information on BMI, age at diagnosis, current treatment, and the presence and nature of any complications. The biochemical studies examined liver and kidney function and included measures of alanine and aspartate aminotransferase, gamma-glutamyl transpeptidase, blood urea nitrogen, creatinine, uric acid, total and HDL cholesterol, triglycerides, and 17 serum proteins.

RESULTS

The present age and duration of diabetes were similar in patients with HNF-1 alpha, HNF-1 beta, or HNF-4 alpha diabetes, as was the age at diagnosis of diabetes in the youngest generation. All subjects were lean. Of the subjects with HNF-1 alpha and HNF-4 alpha diabetes, 50% were treated with insulin, as were all three subjects with HNF-1 beta diabetes. Retinopathy was present in patients with each form of diabetes. None of the subjects with HNF-4 alpha diabetes had evidence of nephropathy, whereas 36% of the patients with HNF-1 alpha diabetes and 100% of those with HNF-1 beta diabetes showed diminished kidney function. The three subjects with HNF-1 beta diabetes also had abnormally high serum creatinine, uric acid, and blood urea nitrogen levels, which are consistent with impaired kidney function, and one of seven subjects with HNF-1 alpha diabetes had a mild elevation in creatinine and blood urea nitrogen levels. These values were within the normal range in the three patients with HNF-4 alpha diabetes. Although the HNFs play a role in regulating the expression of the genes for most, if not all, serum proteins, there was no decrease in the levels of any of the 17 serum proteins examined, and most were within or slightly above the normal range. Lipoprotein(a) [Lp(a)] levels were elevated in the three patients with HNF-4 alpha diabetes and in one patient with HNF-1 beta diabetes, and in a second patient with HNF-1 beta diabetes, Lp(a) was at the upper limit of normal.

CONCLUSIONS

The results indicate that as in white patients, MODY resulting from mutations in the HNF-1 alpha, HNF-1 beta, and HNF-4 alpha genes in Japanese patients may be a severe disease similar to classic type 2 diabetes. In addition, they suggest that patients with HNF-1 beta diabetes may be characterized by diminished kidney function and perhaps abnormal liver function. Further studies are needed to determine whether tests of liver and kidney function will be useful in the diagnosis and subclassification of MODY.

Metabolism of 2,3',4',5-tetrachlorobiphenyl by cytochrome P450 from rats, guinea pigs and hamsters

The metabolism of 2,3',4',5-tetrachlorobiphenyl (TCB) was compared using liver microsomes and six isoforms of cytochrome P450 purified from rats, guinea pigs and hamsters. In microsomal study, the following species differences were observed: 1) Untreated guinea pigs and hamsters but not rats can metabolize this TCB to 3-hydroxy- or 4-hydroxy-2,3',4',5-TCB, 2) Guinea pig microsomes showed only 3-hydroxylating activity, whereas hamster microsomes showed higher activity of 4-hydroxylation than that of 3-hydroxylation. In common with three species, the 3-hydroxylation was accelerated by phenobarbital. The 4-hydroxylation in rats and hamsters was increased by pretreatment with 3-methylcholanthrene and 3,3',4,4',5-pentachlorobiphenyl. The hydroxylation activities of liver microsomes from the three species could be explained by an involvement of different isoforms of cytochrome P450. In addition, it is apparent that hamster CYP1A2 as well as hamster CYP2A8 is involved in the 4-hydroxylation of 2,3',4',5-TCB although it has no activity for 2,2',5,5'-TCB.

New successful treatment with disinfectant for atopic dermatitis

For the treatment of atopic dermatitis, a variety of therapies are used including folk medicine. At present, there is no single treatment which is effective to cure the symptoms of atopic dermatitis completely in all patients. We are drawing attention to the high isolation rate of Staphylococcus aureus when starting disinfectant treatment combined with topical steroid therapies for the purpose of killing S. aureus. As a result, we examined many patients in whom almost a complete remission was obtained even after short periods of therapy, though it had been difficult to obtain improvement by conventional treatments. In many patients, IgE values and reagin antibody titer decrease dramatically soon after starting treatment. As a disinfectant, 10% povidone-iodine solution was used. We investigated also the effect of iodine contained in the povidone-iodine solution on the thyroid gland.

Selectivity of electron-donor- and electron-acceptor-bonded silica packing materials for hydrophobic environmental contaminants in polar and non-polar eluents

Electron-acceptor-bonded stationary phases, 2-(nitrophenyl)ethylsilyl (NPE) and 3-(p-nitrophenoxy)propylsilyl (NPO), and electron-donor-bonded phases, 3-(N-carbazolyl)propylsilyl (CZP), 2-(1-pyrenyl)ethylsilyl (PYE), and 5-coronenylpentylsilyl (COP), were prepared from silica particles and their selectivities were examined in both polar and non-polar solvents for specific isomers of polychlorodibenzo-p-dioxins (PCDDs), hexachloronaphthalenes (HxCNs) and planar and non-planar polychlorobiphenyl (PCB) congeners. Although no single stationary phase was able to separate all the isomer pairs that are coproduced during the synthesis of the PCDDs and HxCNs, pairs can be separated by selecting a suitable stationary phase and solvent. The separation of mixtures of PCDD isomers were found to be most successful with PYE and NPO phases, which yielded the opposite elution orders for each isomer pair that is produced as a mixture. Similar results were obtained for the HxCN isomers that were separated on PYE and CZP phases. The COP phase provided easier separation of non-ortho-substituted and mono-ortho-substituted PCBs from the other PCBs based on the planarity than PYE phase.