CD69-null mice protected from arthritis induced with anti-type II collagen antibodies

CD69, known as an early activation marker antigen on T and B cells, is also expressed on platelets and activated neutrophils, suggesting certain roles in inflammatory diseases. In order to address the role of CD69 in the pathogenesis of arthritis, we established CD69-null mice. CD69-null mice displayed a markedly attenuated arthritic inflammatory response when injected with anti-type II collagen antibodies. Cell transfer experiments with neutrophils, but not T cells or spleen cells, from wild-type mice into CD69-null mice restored the induction of arthritis. These results indicate a critical role for CD69 in neutrophil function in arthritis induction during the effector phase. Thus, CD69 would be a possible therapeutic target for arthritis in human patients.     

Suppressive effects of receptive field surround on neuronal activity in the cat primary visual cortex

Effects of sinusoidal grating stimulus presented outside the classical receptive field (CRF) on neuronal responses were studied in the primary visual cortex of anaesthetized cats. Among 101 cells electrophysiologically recorded, the predominant effect of the stimulus in the receptive field surround (SRF) was the suppression of responses to the CRF stimulation, and the SRF grating suppressed them up to 56% of the responses (44% suppression) to the CRF stimulus alone. The strong suppression was observed more often in layer II/III cells than in other layers and in complex cells more often than in simple cells. The modulatory effects by SRF stimulus might be enhanced by the cortical recurrent excitation particularly in the superficial layers. We also examined whether the modulation by the surround grating exhibits a differential effect according to the presence or absence of figure-ground segregation in the stimulus configuration. For this purpose, effects of stimulus configuration with orientation-, direction-contrast or relative spatial phase difference between CRF and SRF stimuli (figure-ground segregated configuration) were compared with those of uniform configuration of stimulus (non-segregated configuration). There was a population of cells, which exhibited significantly stronger suppression with non-segregated configuration than with figure-ground segregated configuration. Such differential modulation of response by the SRF stimulus in the primary visual cortex is a possible basis of perceptual figure-ground segregation.     

Association of Pasteurella multocida toxin with vimentin

To help understand the molecular mechanisms of Pasteurella multocida toxin (PMT) action, we searched for a cellular protein interacting with PMT. The ligand overlay assay revealed a 60-kDa cellular protein that binds to a region from the 840th to 985th amino acids of the toxin. This protein was identified as vimentin by peptide mass fingerprinting. The N-terminal head domain of vimentin was further found to be responsible for the binding to the toxin.     

Determination of bisphenol A concentrations in human biological fluids reveals significant early prenatal exposure

BACKGROUND: There is broad human exposure to bisphenol A (BPA), an estrogenic endocrine-disrupting chemical widely used for the production of plastic products. BPA is reported to affect preimplantation embryos or fetuses and alter their postnatal development at doses typically found in the environment. We measured contamination of BPA in various kinds of human biological fluids by a novel enzyme-linked immunosorbent assay. METHODS: Blood samples were obtained from healthy premenopausal women, women with early and full-term pregnancy, and umbilical cord at full-term delivery. Ovarian follicular fluids obtained during IVF procedures and amniotic fluids obtained at mid-term and full-term pregnancy were also subject to BPA measurements. RESULTS: BPA was present in serum and follicular fluid at approximately 1-2 ng/ml, as well as in fetal serum and full-term amniotic fluid, confirming passage through the placenta. Surprisingly, an approximately 5-fold higher concentration, 8.3 +/- 8.7 ng/ml, was revealed in amniotic fluid at 15-18 weeks gestation, compared with other fluids. CONCLUSION: These results suggest accumulation of BPA in early fetuses and significant exposure during the prenatal period, which must be considered in evaluating the potential for human exposure to endocrine-disrupting chemicals.     

The 3111T/C polymorphism of hClock is associated with evening preference and delayed sleep timing in a Japanese population sample.

Sleep timing is influenced by the circadian system. Morningness-eveningness (ME) preference in humans is affected by the free-running period, which is determined by circadian clock-relevant genes. In this study, we investigated association between the 3111T/C polymorphism in the 3'-flanking region of hClock (Homo sapiens Clock homolog) and ME preference in 421 Japanese subjects. The Horne-Ostberg ME questionnaire (MEQ) scores showed normal distribution, with mean score of 51.2 +/- 1.4 (range, 25-73), and scores were positively correlated with sleep onset time (r = 0.541, P < 0.001) and wake time (r = 0.513, P < 0.001). MEQ scores were significantly lower in subjects with 3111C/C (n = 12) than in subjects with 3111T/C (n = 106, P < 0.001) or 3111T/T (n = 303, P < 0.001), suggesting a stronger eveningness preference in 3111C/C homozygotes. This group also showed significantly delayed sleep onset (P < 0.001), shorter sleep time (P < 0.001), and greater daytime sleepiness (P < 0.001) in comparison to parameters in the subjects with the 3111T allele. There was no significant difference in any of these parameters between the 3111C/T and 3111T/T genotypes. The influence of the 3111T/C polymorphism on ME preferences in Caucasian populations remains controversial. The present findings in a Japanese population sample, which should have a relatively low risk of population stratification effects, suggest the significance of the association of the 3111C/C allele of hClock with evening preference.     

Identification of fibroin-derived peptides enhancing the proliferation of cultured human skin fibroblasts

We previously reported that the fibroin of the silkworm Bombyx mori enhanced the proliferation of cultured human skin fibroblasts. In this work, the fibroin was digested by chymotrypsin, and the resulting peptide fragments were fractionated and assayed for their biological activity. Two peptides that promoted fibroblast growth were isolated and identified to be VITTDSDGNE and NINDFDED. Both sequences are found in the N-terminal region of the fibroin polypeptide and are thought to be the active principle of fibroblast growth-promoting activity.     

Surface carbohydrates as recognition determinants in non-opsonic interactions and intracellular viability of group B Streptococcus strains in murine macrophages

Mononuclear cells have been found to play a key role in phagocytosis and eventual killing of group B streptococci (GBS). The rich array of sugars on bacterial surface plus the presence of membrane-associated lectin-receptors on the macrophage suggests that this is a likely means for GBS recognition by these host defense cells. Macrophages have been shown to bind GBS in the absence of serum components. However, participation of carbohydrate moieties in GBS intracellular survival had not been completely elucidated. The aim of this study was to assess the involvement of sugars on adherence and intracellular viability in murine macrophages of GBS serotypes Ia (85147 and 90222 strains), III (80340 and 90356 strains) and V (88641 and 90186 strains) isolated from assymptomatic carriers and patients, respectively. Most isolates showed higher adherence within 2-h incubation. Only 90222-Ia strain exhibited progressive adherence rate until 12-h incubation. All strains showed intracellular viability during first 0.5-h of incubation. Except for 90186-V strain that survived only for 2 h, strains of all serotypes tested were found to survive 24 h into macrophages. Treatments of bacteria by glycosidases inhibited macrophage interaction with GBS strains at varied levels. Neuraminidase inhibited 90-97% adherence and 100% intracellular survival of GBS strains (P<0.0001). Host cell treatments with Rhamnose, N-acetyl-D-glucosaminidase and Fucose (5 mg/ml) inhibited adherence and intracellular viability of GBS strains at varied levels. Removal of GlcNAc residues of invasive GBS isolates enhanced intracellular viability, suggesting that GlcNAc residues may act by intercepting the expression of hidden receptors probably related with invasiveness and survival within macrophages. Lastly, our results demonstrate involvement of sialic acid specific receptors on macrophages and lectinophagocytosis in non-opsonic interaction and survival of GBS invasive isolates.     

Deficiency of theory of mind in patients with remitted mood disorder

BACKGROUND: Recent researches on theory of mind (ToM) in patients with mood disorders have revealed deficits of ToM ability during episodes. In this study, we aimed to test ToM ability among patients with unipolar or bipolar depression currently in remission. METHODS: ToM ability and IQ obtained by Wechsler Adult Intelligence Scale-Revised (WAIS-R) were evaluated in 50 patients with remitted depression, who met the criteria of mood disorders of DSM-IV, and 50 matched healthy controls. RESULTS: The patients with mood disorders showed statistically significant impairment in a second-order false question (Fisher's Exact Test p < 0.0001). No significant difference was shown in the other three areas of ToM between the patients and the controls. In addition, no correlation of the four areas of ToM with IQ obtained by WAIS-R was found. LIMITATIONS: The relation of ToM deficit to other specific cognitive impairment was not examined. CONCLUSIONS: Our results suggest that depressive patients in symptomatic remission have a lower ability of second-order false belief. The ToM impairment suggests a decline of skillful social relationships. Evaluation of ToM ability in depressive patients in remission may be useful to provide treatment for better social adjustment.