Triply bridged dinuclear ruthenium complexes bearing alkylbis(2-pyridylmethyl)amine in the mixed-valence state of Ru(ii)-Ru(iii).

Triply halogeno and methoxido-bridged dinuclear ruthenium complexes bearing a tridentate ancillary ligand, alkylbis(2-pyridylmethyl)amine (alkyl, ethyl and benzyl), in the Ru(ii)-Ru(iii) mixed-valence state were synthesized by reduction reactions of the trichloridoruthenium(iii) complex, fac-[RuIIICl3(ebpma)], followed by chlorido-substitution and oxidation reactions in air. The conversion of the bridging ligands of the diruthenium complexes was also made possible through reduction of the dinuclear core. The electronic structures of the mixed-valence state were investigated by electron spin resonance (ESR), X-ray crystallography, electrochemical measurements and UV-vis-near infrared (NIR) spectroscopy. The mixed-valence state of all the triply bridged complexes was stable and classified as Class III.

Assessment of relevant fungal species in clinical solid wastes.

The study aimed to determine the fungal diversity in clinical waste samples from a healthcare facility in Penang Malaysia. Different fungi species were detected in 83.75 % of the 92 clinical waste samples that were screened from different sections of the healthcare facility. One hundred fifty fungal isolates comprising of 8 genera and 36 species were obtained. They were purified by using single spore isolation technique. Subsequently, the isolates were identified by phenotypic method based on morphological and culture characteristics on different culture media. Among all fungal isolates, Aspergillus spp. in section Nigri 10.2 %, Aspergillus niger 9.5 %, Aspergillus fumigatus 8.8 %, Penicillium. simplicissium 8 %, Aspergillus tubingensis 7.3 %, Aspergillus terreus var. terreus 6.6 %, Penicillium waksmanii 5.9 % and Curvularia lunata 6.5 % were the most frequent. Among five sections of the Wellness Centre, the clinical wastes collected from the diagnostic labs of haematology section had the highest numbers of fungal species (29 species). Glove wastes had the highest numbers of fungal species (19 species) among 17 types of clinical wastes screened. Among all fungal species, Aspergillus spp. exhibited higher growth at 37 °C than at 28 °C, indicating the potential of these opportunistic fungi to cause diseases in human. These results indicated the potential of hospital wastes as reservoirs for fungal species.

Kumanasamuha geaster sp. nov., an anamorph of Chorioactis geaster from Japan.

A new species of Kumanasamuha is described and illustrated from axenic single-spore isolates of Chorioactis geaster. The characteristics of conidia and hyphae are the same as the dematiaceous hyphomycete observed on decayed trunks of Quercus spp., where C. geaster appeared in the field in Japan. Our results indicated that C. geaster in situ colonizes decayed trunks of Quercus spp.

Tumour formation by single fibroblast growth factor receptor 3-positive rhabdomyosarcoma-initiating cells.

BACKGROUND: The hypothesis that malignant tumours are generated by rare populations of cancer stem cells that are more tumourigenic than other cancer cells has gained increasing credence. The objective of this study was to identify and characterise a subpopulation of human sarcoma-initiating cells. METHODS: We examined established rhabdomyosarcoma cell lines by flow cytometry. Tumourigenesis was examined by xenograft models. Real-time PCR and immunohistochemistry were performed to examine the gene expression using cell lines and biopsy specimens. RESULTS: Rhabdomyosarcoma cell lines included small populations of fibroblast growth factor receptor 3 (FGFR3)-positive cells. FGFR3-positive KYM-1 and RD cells were more strongly tumourigenic than FGFR3-negative cells. In addition, xenoengraftment of 33% of single FGFR3-positive KYM-1 cells yielded tumour formation. Stem cell properties of FGFR3-positive cells were further established by real-time PCR, which demonstrated upregulation of undifferentiated cell markers and downregulation of differentiation markers. We showed that in the absence of serum, addition of basic fibroblast growth factor maintained and enriched FGFR3-positive cells. On the other hand, ciliary neurotrophic factor reduced the proportion of FGFR3-positive cells. Real-time PCR and immunohistochemical examination revealed that embryonal rhabdomyosarcoma patient biopsy specimens were found to over-express FGFR3. CONCLUSIONS: Our findings suggest that rhabdomyosarcoma cell lines include a minor subpopulation of FGFR3-positive sarcoma-initiating cells, which can be maintained indefinitely in culture and which is crucial for their malignancy.

Oxygen at high pressures: a theoretical approach to monoatomic phases.

We have studied the ζ-phase of solid oxygen using the generalized gradient approximation in the density functional approach. Calculations of total energies and pressures have been carried out for the prototype of diatomic ζ-phase and other hypothetical monoatomic crystal structures. The diatomic phase was found to be stable over a wide range of pressure (100-2000 GPa). The stacking of molecular layers is discussed in comparison with the available experimental data.

Theoretical studies on electronic states of Rh-C60. Possibility of a room-temperature organic ferromagnet.

A possible mechanism for a ferromagnetic interaction in the rhombic (Rh) form of C60 (Rh-C60) is suggested on the basis of theoretical studies in relation to cage distortion of the C60 unit in the polymerized 2D-plane. Band structure calculations on Rh-C60 show that cage distortion leads to competition between diamagnetic and ferromagnetic states,which give rise to the possibility of thermally populating the ferromagnetic state.

Effect of recombinant human bone morphogenetic protein-2 on bone formation in alveolar ridge defects in dogs.

This study was designed to evaluate the effect of recombinant human bone morphogenetic protein-2 (rhBMP-2) combined with poly D, L lactic-co-glycolic acid (PLGA)/gelatin sponge complex (PGS) on the formation of bone in critically sized marginal defects of the mandible in dogs. Three months after extraction of the pre-molar teeth, rectangular bone defects (10 x 8 x 7 mm) were made in both sides of the mandible. A PGS block soaked in rhBMP-2 (400 microgram/ml) was implanted into one defect (BMP (+) group). As control, an untreated PGS block was implanted into the contralateral defect (BMP (-) group). 2, 4, 8, and 12 weeks after implantation, the defects were examined. In the BMP (+) group, newly formed bone was found in all defects from 4 weeks onward and was marked at 12 weeks. In contrast, the BMP (-) group showed no appreciable new bone formation, even at 12 weeks. Moreover, density of newly formed bone in the BMP (+) group was similar to that of the surrounding cortical bone at 12 weeks. These findings suggest that rhBMP-2/PGS is an effective bone substitute for reconstructive surgery of the dog mandible.

[Medical and educational support to children with neuromuscular disorders in schools: an analysis based on a questionnaire to teachers].

To clarify the medical and educational support necessary for ordinary school life of children with neuromuscular disorders, a questionnaire was sent to their homeroom teachers. The 13 outpatients consisted of 7 with Duchenne muscular dystrophy, 5 other muscular dystrophies, and 1 with another myopathy. Their teachers desired the environment and system, such as elevators and personnel to support their movements, should be improved. Regarding the school curriculum, special advice of medical staff was considered to be necessary to provide physical education and to promote their well-retained activities. The teachers regarded it valuable to teach them together with healthy children, for the children with or without neuromuscular disorders, teachers, and people in the community. In the future, it is expected that national sanatariums and schools for the handicapped will function as special facilities that are open to the community for general counselling and provide various informations. Pediatric neurologists should play a role as managers caring for the patients, their families, teachers, schools, and communities.

Developing germ cells in mouse testis express pheromone receptors.

Pheromone receptors are expressed in the accessory olfactory system, which is vital for non-specific chemical communication and for sexual behavior. Under the hypothesis that some of the pheromone molecules released from female reproductive organs might regulate sperm chemotaxis or chemokinesis, we examined whether the V1R type pheromone receptor mRNAs are expressed in developing germ cells. By a reverse transcription-PCR method, we obtained nine kinds of cDNA fragments belonging to the receptor family. In situ hybridization analysis in testicular sections using probes of testicular pheromone receptors (TVRs) revealed that TVR mRNAs were expressed by spermatids. TVRs were also expressed in the accessory olfactory organ. In the testis, hybridization signals were localized in subsets of the seminiferous tubules, suggesting that TVRs were expressed by selective subsets of the spermatids. In situ hybridization study suggests also that each sperm expresses multiple pheromone receptors. The testicular pheromone receptors might have an important role in the maturation and/or migration of sperm.

Two mirror-image sensory maps with domain organization in the mouse main olfactory bulb.

The glomerular sheet in the olfactory bulb (OB) provides an olfactory sensory map identifying which odorant receptors (ORs) in the nose are activated by inhaled odorants. How are the glomeruli spatially arranged in the OB? Using OCAM and neuropilin-1 (NP1) as molecular markers for target glomeruli of distinct subsets of olfactory axons, we demonstrate here that glomeruli are parceled into topographically distinct domains. Spatial arrangement of these domains suggests that each OB contains two mirror-image maps of the glomeruli. In situ hybridization shows that the glomeruli representing the same OR are symmetrically arranged; one in a domain in the lateral hemisphere and the other in a corresponding domain in the medial hemisphere of the OB. These results suggest that OB contains two symmetrical OR maps with similar domain organization.

Long-term medical, educational, and social prognoses of childhood-onset epilepsy: a population-based study in a rural district of Japan.

The long-term prognosis of childhood-onset epilepsy has rarely been studied in a general population. We examined the long-term medical, educational, and social outcomes in individuals with a history of childhood-onset epilepsy aged 20 years or older in a defined area of Japan. Furthermore, the patients' recognition of epilepsy as well as the parents' concerns about the prognosis of epilepsy were also surveyed. After a mean follow-up period of 18.9 years, we had sufficient data on 148 surviving patients aged 20-38 years (mean, 26. 0 years) and seven dead patients. The follow-up rate was 92.8%. In the overall group, the percentages of those who had had each of the following were as follows: (a) 5-year remission, 62.8%; (b) a relapse of seizures, 17.4%; (c) psychiatric complications, 2.7%; (d) mortality, 4.5%; (e) attendance at regular classes of an ordinary school during compulsory education, 71.6%; (f) entrance to high school, 65.5%; (g) employment, 67.4%; (h) marriage, 23.0%; and (i) acquisition of a driver's license, 54.7%. The educational and social variables of the control population were as follows: (e) 99.1, (f) 97.0, (g) 96.6, (h) 51.9, and (i) 94.8%. In the 99 patients of normal intelligence, the results of the same analysis were as follows: (a) 75.8, (b) 10.7, (c) 0, (d) 0.6, (e) 100, (f) 96.0, (g) 95.2, (h) 33.3, and (i) 77.8%, in contrast to the corresponding variables of the 49 patients with mental retardation, that is, (a) 36.7, (b) 44.4, (c) 8.2, (d) 12.2, (e) 14.3, (f) 6.1, (g) 20.4, (h) 2.0, and (i) 4.1%, respectively. The best predictors of seizure remission included an early response to therapy, a low frequency of seizures or an absence of status epilepticus prior to therapy, and normal mental development. As for the current awareness of epilepsy and its prognosis, nearly 40% of the patients did not know the true name of their illness, and the same proportion of parents were still anxious about the prognosis even if their children had been taken off medication. Our data show that the majority of patients with childhood-onset epilepsy have a favorable long-term medical prognosis in terms of seizure remission and psychiatric complications, whereas they have a higher mortality rate and lower levels of educational background as well as employment and marital status compared with the general population. However, except for the low marriage rate for the younger age group and the low rate of holding a driver's license, patients of normal intelligence appear to have more favorable long-term prognoses in terms of educational and social aspects as well. In Japan, individuals with epilepsy may not seek a driver's license because of the law.

[Clinical study on risk management for dental implant treatment--Part 1. Clinical retrospective study on the medically compromised patients at clinic for oral implant].

A retrospective study on medically compromised patients was made using 1,000 outpatients who visited the Clinic for Oral Implant, University Hospital, Faculty of Dentistry, Tokyo Medical and Dental University between April 1995 and June 1998. The results were as follows: 1. 35.3% (353 patients: 140 males and 213 females) of the outpatients were medically compromised. 2. The greatest number of medically compromised patients was in the 50-59 age group (118 cases), followed by those in the 40-49 and 60-69 age groups. 3. The highest ratio of medically compromised patients was in the 60-69 age group (48.2%), followed by those in the 70-79 and 50-59 age groups. 4. Among the 353 patients, 96 (27.2%) underwent surgical treatment such as insertion of implant (68 cases), removal of implant, extraction of tooth, and free gingival graft. 5. Among the 68 patients who underwent insertion of implant, in a classification by type of disease, the patients with cardiovascular diseases were the most numerous (33.9%), followed by metabolic and digestive tract diseases. 6. All surgical treatments of implant insertion were performed under local anesthesia, while monitoring cardiac and respiratory function, and SpO2. Among the 68 patients, 9 underwent operation under intravenous sedation and 2 under nitrous oxide inhalation sedation. All 11 patients had hypertension. The results suggested that identification of preoperative risk factors, precise recognition of general condition, and establishment of control system are important to manage medically compromised patients for dental implant treatment.

The olfactory bulb: coding and processing of odor molecule information.

Olfactory sensory neurons detect a large variety of odor molecules and send information through their axons to the olfactory bulb, the first site for the processing of olfactory information in the brain. The axonal connection is precisely organized so that signals from 1000 different types of odorant receptors are sorted out in 1800 glomeruli in the mouse olfactory bulb. Individual glomerular modules presumably represent a single type of receptor and are thus tuned to specific molecular features of odorants. Local neuronal circuits in the bulb mediate lateral inhibition among glomerular modules to sharpen the tuning specificity of output neurons. They also mediate synchronized oscillatory discharges among specific combinations of output neurons and may contribute to the integration of signals from distinct odorant receptors in the olfactory cortex.

Nonconvulsive status epilepticus in eyelid myoclonia with absences--evidence of provocation unrelated to photosensitivity.

A 10-year old girl with eyelid myoclonia with absences (EMA) in whom nonconvulsive status epilepticus developed shortly after awakening is described. A video-polygraphic recording during the status showed the characteristic eye-closure provocation of eyelid myoclonia with upward deviation of the eyeballs and brief absences. Ictal EEG showed generalized polyspikes concomitant with eyelid myoclonia, while absences were accompanied by 3.5 Hz polyspike-wave complexes on EEG. This condition occurred even in total darkness as well as even after seizures precipitated by bright sunlight had been eliminated by medication. The present case suggests that the eye closure mechanism could be a more potent precipitating factor than photosensitivity in the pathophysiology of EMA.

Repression of nitrogenase by ethanol in nitrogen-deprived cultures of Rhodovulum sulfidophilum.

Light-dependent H2 evolution did not occur in nitrogen-deprived cultures of Rhodovulum sulfidophilum in the presence of ethanol. When ethanol was added to cells which had been grown with ammonia, derepression of the nitrogen fixation genes (nifHD) was inhibited at an ethanol concentration of 1 mM. On the other hand, when cells had nitrogenase-catalyzed proton-reducing activity prior to ethanol addition, reduction of the nifHD transcript level did not occur after the addition. In cells grown with ammonia, concomitant addition of an auxiliary oxidant such as dimethylsulfoxide or sodium bicarbonate resulted in derepression of nitrogenase activity in the presence of ethanol. These results suggest that the electron-accepting process is necessary for derepression of nif genes in cultures which use ethanol as the electron donor.

[Fibrinogen affects blood and bone marrow cell functions on titanium in vitro].

Host-derived blood protein adsorption is much more rapid than the migration of cells to foreign surfaces, so the effect of host proteins in blood on blood cells and bone marrow cells was investigated by means of in vitro culturing of blood and bone marrow cells on titanium. A material preincubated with plasma induced high nonspecific esterase (NSE) activity and polymorphonuclear neutrophil (PMN) elastase activity, but neither a serum- nor albumin-coated material had the same effect as the plasma-coated material. Therefore, attention was paid to fibrinogen. On titanium coated with fibrinogen increases in not only NSE activity and PMN elastase activity in blood and bone marrow, but also tartrate-resistant acid phosphatase (TRACP) activity were observed in bone marrow cultures. A decrease in alkaline phosphatase (ALP) activity was also observed in the cultures. These changes of bone marrow cultures were reversed by the addition of recombinant human bone morphogenetic protein-2 to the cultures. These results suggested that bleeding around titanium affects the function of macrophages or neutrophils due to the effect of fibrinogen. Furthermore, it was suggested that this factor may affect the functions of osteoblasts anti osteoclasts around a titanium implant with the inevitable side effects of implantation in bone tissue: bleeding and clotting.

Computation of molecular information in mammalian olfactory systems.

The olfactory system is unique in that the sensory input is in the form of molecular information carried in odour molecules and that a huge variety of compounds can function as odour molecules. The mammalian olfactory system has neuronal networks that can process and integrate the molecular information for discrimination of odour molecules and for perception of olfactory images of objects. Recent rapid advances have begun to provide new insights into the functional logic employed by the main olfactory system for odour discrimination, for odour classification and for olfactory perception of objects. This review discusses how the odour molecule information is encoded, transmitted, processed and decoded at distinct anatomical structures (sensory epithelium, olfactory bulb and olfactory cortex) of the olfactory nervous system. We also discuss the functional network in the accessory olfactory system with regard to the processing of pheromonal information.

Synthesis of a Lectin in Both Mycelia and Fruit Bodies of the Ascomycete Mushroom Aleuria aurantia.

In several organisms that form fruit bodies, the synthesis of lectins is developmentally regulated. Aleuria aurantia is an ascomycete that forms a fruit body known as orange peel mushroom. To find whether the mycelia of this organism synthesize a lectin, mycelial isolates were obtained from a wild fruit body by spore germination and regeneration from a fragment of the fruit body. The isolates were identified as A. aurantia by analysis of their DNA. The mycelial isolates synthesized a lectin with the same properties as those of fruit-body lectin in terms of subunit molecular mass, immunochemical reactivity, binding specificity for L-fucose, and N-terminal amino acid sequence. Vegetatively growing mycelia synthesized as much lectin as the fruit body, so such synthesis was not developmentally regulated, unlike some other organisms that form fruit bodies.

Effect of a titanium surface on bone marrow-derived osteoblastic cells in vitro.

The initial interaction between a titanium implant and the surrounding cancellous bone tissue was investigated by means of in vitro cultures of bone marrow-derived osteoblastic clone TMS-12 cells. Proliferation of TMS-12 cells cultured on a titanium surface was significantly reduced compared with that of control cells cultured directly on plastic, but alkaline phosphatase activity was the same as control cells. Co-culture of spleen cells with TMS-12 cells in the presence of a 1 alpha,25-dihydroxyvitamin D3 on titanium resulted in significant inhibition of tartrate-resistant acid phosphatase activity compared to control cultures on plastic. More prostaglandin E2 (PGE2) was produced by cells grown on a titanium surface than on plastic tissue-culture plates. On the other hand, mouse calvaria-derived osteogenic MC3T3-E1 cells, known to proliferate well on titanium, released similar amounts of PGE2 on titanium surfaces as on plastic tissue culture plates, indicating additional marked differences between the two osteoblastic cell types in response to a titanium surface. These results suggest that the reaction of bone marrow-derived osteoblastic cells to a titanium surface may fundamentally differ from that of calvaria-derived osteoblastics even though both cells are from bone tissue.