Unification of the genera Serpulina and Brachyspira, and proposals of Brachyspira hyodysenteriae Comb. Nov., Brachyspira innocens Comb. Nov. and Brachyspira pilosicoli Comb. Nov

The phylogenetic positions of Serpulina hyodysenteriae, Serpulina innocens, Serpulina pilosicoli and Brachyspira aalborgi were studied. Complete 16S ribosomal DNA sequences of these three species and B. aalborgi revealed that their 16S rDNA sequences were related more than 96.0%. The mol% guanine plus cytosine (G+C) of B. aalborgi DNA was 27.1, and was similar to those of the 3 members of the genus Serpulina. The homologous rates using 31P-labeled B. aalborgi chromosome DNA in DNA-DNA reassociation tests were 22.0% to S. hyodysenteriae, 19.1% to S. innocens and 17.2% to S. pilosicoli. Therefore, we propose to transfer the three species of the genus Serpulina to the genus Brachyspira. Descriptions of Brachyspira hyodysenteriae comb. nov., Brachyspira innocens comb. nov. and Brachyspira pilosicoli comb. nov., and an emended description of B. aalborgi are given. Phenotypic characteristics of the 4 members of the genus Brachyspira were also studied. They fermented fructose, galactose, glucose, lactose, maltose, mannose, raffinose and trehalose; however, B. aalborgi did not ferment raffinose. All of them hydrolyzed esculin but did not produce indole except for B. hyodysenteriae. The protein profile of B. aalborgi was different from those of the four strains of B. hyodysenteriae, B. innocens and B. pilosicoli, but the heavy bands with molecular sizes of 49.4 and 52.3 kDa of B. aalborgi were quite similar to those of B. innocens in the points of quantity and molecular size. In immunoblotting tests, B. aalborgi reacted well with anti-B. innocens and B. pilosicoli sera, but reacted weakly with anti-B. hyodysenteriae serum. Only one heavy band and several faint bands were revealed by the reaction between B. aalborgi and anti-B. hyodysenteriae serum, and the heavy band was common among these strains.

Orbit-related long-term climate cycles revealed in a 12-Myr continental record from Lake Baikal

Quaternary records of climate change from terrestrial sources, such as lake sediments and aeolian sediments, in general agree well with marine records. But continuous records that cover more than the past one million years were essentially unavailable until recently, when the high-sedimentation-rate site of Lake Baikal was exploited. Because of its location in the middle latitudes, Lake Baikal is highly sensitive to insolation changes and the entire lake remained uncovered by ice sheets throughout the Pleistocene epoch, making it a valuable archive for past climate. Here we examine long sediment cores from Lake Baikal that cover the past 12 million years. Our record reveals a gradual cooling of the Asian continental interior, with some fluctuations. Spectral analyses reveal periods of about 400 kyr, 600 kyr and 1,000 kyr, which may correspond to Milankovitch periods (reflecting orbital cycles). Our results indicate that changes in insolation were closely related to long-term environmental variations in the deep continental interior, over the past 12 million years.

Identification of intermediately virulent Rhodococcus equi isolates from pigs

We recently reported the existence of Rhodococcus equi isolates with at least three virulence levels, isolated from AIDS patients: virulent R. equi having 15- to 17-kDa antigens that kills mice with 10(6) cells, intermediately virulent R. equi having a 20-kDa antigen that kills mice with 10(7) cells, and avirulent R. equi that does not kill mice with 10(8) cells or more (S. Takai, Y. Imai, N. Fukunaga, Y. Uchida, K. Kamisawa, Y. Sasaki, S. Tsubaki, and T. Sekizaki, J. Infect. Dis. 172:1306-1311, 1995). Virulent R. equi having the 15- to 17-kDa antigens has been isolated frequently from horses and their environment, but the source of intermediately virulent R. equi having the 20-kDa antigen is poorly understood. There are many reports of the isolation of R. equi from the lymph nodes of pigs with and without lesions resembling those of tuberculosis. Therefore, we analyzed antigens of R. equi isolates from the submaxillary lymph nodes of pigs by immunoblotting with monoclonal antibodies against these virulence-associated antigens. Immunoblots of whole-cell antigen preparations of R. equi pig isolates revealed the presence of the 20-kDa antigen in almost all the pig isolates studied, and these isolates were intermediately virulent for mice. We also demonstrated that the expression of the 20-kDa antigen and its pathogenicity in mice were associated strongly with the presence of five large, distinct plasmids of 70 to 95 kb; two of the five plasmids from pig isolates were the same sizes as those from human isolates. These results suggest that R. equi having the 20-kDa antigen exists in the submaxillary lymph nodes of pigs and that the source of infection in some human cases might be associated with pigs and their environment.

Isotopic Pu, Am and Cm signatures in environmental samples contaminated by the Fukushima Dai-ichi Nuclear Power Plant accident

Dust samples from the sides of roads (black substances) have been collected together with litter and soil samples at more than 100 sites contaminated heavily in the 20-km exclusion zones around Fukushima Dai-ichi Nuclear Power Plant (FDNPP) (Minamisoma City, and Namie, Futaba and Okuma Towns), in Iitate Village located from 25 to 45 km northwest of the plant and in southern areas from the plant. Isotopes of Pu, Am and Cm have been measured in the samples to evaluate their total releases into the environment from the FDNPP and to get the isotopic compositions among these nuclides. For black substances and litter samples, in addition to Pu isotopes, (241)Am, (242)Cm and (243,244)Cm were determined for most of samples examined, while for soil samples, only Pu isotopes were determined. The results provided a coherent data set on (239,240)Pu inventories and isotopic composition among these transuranic nuclides. When these activity ratios were compared with those for fuel core inventories in the FDNPP accident estimated by a group at JAEA, except (239,240)Pu/(137)Cs activity ratios, fairly good agreements were found, indicating that transuranic nuclides, probably in the forms of fine particles, were released into the environment without their large fractionations. The obtained data may lead to more accurate information about the on-site situation (e.g., burn-up, conditions of fuel during the release phase, etc.), which would be difficult to get otherwise, and more detailed information on the dispersion and deposition processes of transuranic nuclides and the behavior of these nuclides in the environment.

Isolation of virulent and intermediately virulent Rhodococcus equi from soil and sand on parks and yards in Japan

Rhodococcus equi is an emerging opportunistic pathogen of human immunodeficiency virus-infected patients. However, little is known about the distribution of virulent and intermediately virulent R. equi in human environment. In the present study, R. equi was isolated from 173 of 234 (73.9%) samples collected from soil and sand on 115 parks and 49 yards in Japan. The numbers of R. equi from soil and sand ranged from 2.5 x 10(1) to 1.2 x 10(5) per gram of sample. None of 1,294 isolates from those samples showed virulence-associated 15- to 17-kDa antigens and a 20-kDa antigen. These results suggest that avirulent R. equi is widespread in parks and yards, but the human environment has not been contaminated with virulent and intermediately virulent R. equi strains yet.

Isolation and analysis of bacteria associated with spores of Gigaspora margarita

AIMS

The aim of this work was to observe bacteria associated with the spores of Gigaspora margarita, an arbuscular mycorrhizal fungus (AMF).

METHODS AND RESULTS

First, a direct analysis of DNA from sterilized spores indicated the bacteria belonging to the genus Janthinobacterium. In the second assay, two bacterial strains were isolated by osmosis from protoplasts, which were derived from spores by using two particular enzymes: lysing enzymes and yatalase. After isolation, cultivation and identification by their DNA as performed in the first experiment, the species with the closest relation were Janthinobacterium lividum (KCIGM01) and Paenibacillus polymyxa (KCIGM04) isolated with lysing enzymes and yatalase respectively. Morphologically, J. lividum was Gram negative and oval, while P. polymyxa was also oval, but Gram positive. Both strains had antagonistic effects to the pathogenic fungi Rosellimia necatrix, Pythium ultimum, Fusarium oxysporum and Rhizoctonia solani. In particular, J. lividum was much stronger in this role. However, in phosphorus (P) solubilization P. polymyxa functioned better than J. lividum.

CONCLUSIONS

This experiment had revealed two new bacteria species (P. polymyxa and J. lividum), associated with AMF spores, which functioned to suppress diseases and to solubilize P.

SIGNIFICANCE AND IMPACT OF THE STUDY

AMF spores could be a useful source for bacterial antagonists to soil-borne diseases and P solubilization.

[Effects of Er:YAG laser irradiation on human extracted teeth]

The ablation effects of the Erbium:YAG laser (wave length: 2.94 microns) on the human extracted teeth were examined histopathologically. The enamel surface of the human extracted tooth was irradiated by the laser at 500 mJ, 1 pps or 3 pps: 3, 15, 30, 50 and 100 shots. After observation under a dissecting microscope, the teeth were placed in a demineralizing solution of 0.1 M lactate buffer with 6% hydroxyethyl cellulose (pH 4.5) in order to evaluate the acid resistance of the enamel adjacent to the ablated area. After 4 days, the degree of demineralization of the surrounding enamel was assessed by contact microradiography. The result showed that every irradiated tooth had a clear-cut defect, and almost all the teeth had acquired acid resistance at the enamel surrounding the ablated portion. The other experiment was carried out to estimate the effects of the Er:YAG laser through a contact probe. The enamel, dentin and cementum of the extracted teeth were irradiated at 39 mJ or 74 mJ, 10 pps; 10 shots. The teeth were observed under a dissecting microscope. The result clearly indicated that the Er:YAG laser guided by the contact probe could also produce a defect in the dental hard tissue. The above-mentioned findings suggested that the Er:YAG laser could pave the way for the cavity preparation with acid-resistant cavity margin.

Novel multilayer Ti foam with cortical bone strength and cytocompatibility

The major functions required for load-bearing orthopaedic implants are load-bearing and mechanical or biological fixation with the surrounding bone. Porous materials with appropriate mechanical properties and adequate pore structure for fixation are promising candidates for load-bearing implant material. In previous work, the authors developed a novel titanium (Ti) foam sheet 1-2mm thick by an original slurry foaming method. In the present work, novel Ti foam is developed with mechanical properties compatible with cortical bone and biological fixation capabilities by layer-by-layer stacking of different foam sheets with volumetric porosities of 80% and 17%. The resulting multilayer Ti foam exhibited a Young's modulus of 11-12GPa and yield strength of 150-240MPa in compression tests. In vitro cell culture on the sample revealed good cell penetration in the higher-porosity foam (80% volumetric porosity), which reached 1.2mm for 21 days of incubation. Cell penetration into the high-porosity layers of a multilayer sample was good and not influenced by the lower-porosity layers. Calcification was also observed in the high-porosity foam, suggesting that this Ti foam does not inhibit bone formation. Contradictory requirements for high volumetric porosity and high strength were attained by role-sharing between the foam sheets of different porosities. The unique characteristics of the present multilayer Ti foam make them attractive for application in the field of orthopaedics.

Transmission of circulating cell-free AA amyloid oligomers in exosomes vectors via a prion-like mechanism

Recent studies clearly demonstrated that several types of pathogenic amyloid proteins acted as agents that could transmit amyloidosis by means of a prion-like mechanism. Systemic AA amyloidosis is one of the most severe complications of chronic inflammatory disorders, particularly rheumatoid arthritis. It is well known that, similar to an infectious prion protein, amyloid-enhancing factor (AEF) acts as a transmissible agent in AA amyloidosis. However, how AEF transmits AA amyloidosis in vivo remained to be fully elucidated. In the present study, we focused on finding cell-free forms of AEF and its carriers in circulation by using the murine transfer model of AA amyloidosis. We first determined that circulating cell-free AEF existed in blood and plasma in mice with systemic AA amyloidosis. Second, we established that plasma exosomes containing AA amyloid oligomers derived from serum amyloid A had AEF activity and could transmit systemic AA amyloidosis via a prion-like mechanism. These novel findings should provide insights into the transmission mechanism of systemic amyloidoses.

Decrease of nitric oxide end-products during coronary circulation reflects elevated basal coronary artery tone in patients with vasospastic angina

The aim of this study was to investigate the role of nitric oxide (NO) in the coronary circulation and its relation to basal coronary artery tone in patients with vasospastic angina (VSA). We evaluated the level of nitric oxide end-products (NOx; nitrite + nitrate) in coronary circulation blood using an HPLC-Griess system for nine patients with VSA and nine control patients. All of the patients with VSA experienced focal spasm in the proximal to middle segments of the left anterior descending coronary artery (LAD) in response to intracoronary injection of ergonovine maleate. The luminal diameter of the coronary artery was measured in each patient by quantitative coronary arteriography. Blood samples for NOx measurement were obtained from the coronary sinus (NOxV) and the ostium of the left coronary artery (NOxA). The NOx difference, calculated from the coronary venous-arterial difference in NOx, was close to zero for the control patients whereas it was clearly negative for the patients with VSA. In addition, the NOx difference in the patients with VSA showed a negative correlation with basal coronary artery tone (r = -0.91, p < 0.01) and a positive correlation with the dose of ergonovine required for spasm provocation (r = 0.77, p < 0.05). These results indicate that increased basal coronary artery tone and higher susceptibility to ergonovine in patients with VSA would be a consequence of coronary endothelial dysfunction as is indicated by NOx.

Radiation-induced osteosarcoma of the calvaria--case report

The authors report a case of radiation-induced calvarial osteosarcoma. A 58-year-old female received subtotal removal of the pituitary adenoma and 5000 rads postoperative irradiation. Seven years later, an osteoblastic osteosarcoma occurred in the frontotemporal region. She received total tumor removal and chemotherapy. However, computed tomography subsequently revealed multiple small lesions at the margin of the bone flap. A chest x-ray film demonstrated lung metastasis. Local recurrence and lung metastasis require careful attention in radiation-induced osteosarcoma patients.

Delusional parasitosis in dementia with Lewy bodies: a case report

BACKGROUND

Dementia with Lewy bodies (DLB) is characterized by fluctuating cognitive impairments, recurrent visual hallucinations, the motor symptoms of parkinsonism and REM sleep behavior disorder. Various neuropsychiatric symptoms including hallucination and delusions occur frequently; however, delusional parasitosis is rare in DLB. Here, we report a case of DLB patient with delusional parasitosis.

CASE PRESENTATION

The patient was an 89-year-old woman. At the age of 88, she began to complain her oral cenesthopathy, and developed cognitive decline, delusional parasitosis and parkinsonism. As a result of examination, she was diagnosed as DLB and treated with combination of donepezil 5 mg/day and aripiprazole 1.5 mg/day, and her complaint was disappeared.

CONCLUSIONS

Further studies are needed to investigate the association between delusional parasitosis and underlying pathophysiology of DLB, and the utility of antipsychotics for delusional parasitosis in DLB has to be examined through more cases.

Nonamyloidotic nephrotic syndrome in Waldenström's macroglobulinemia

Severe nephrotic syndrome developed in an 83-year-old Japanese man with Waldenström's macroglobulinemia. Treatment with corticoid remarkably improved the proteinuria. Autopsy disclosed no deposit of amyloid in the kidneys but a slight infiltration of atypical lymphocytes. A considerable number of glomeruli showed mesangial cell proliferation and global or segmental thickening of the basement membrane with occasional double tracks. Immunofluorescent studies revealed deposits of IgM but not IgG, IgA and C3 along the basement membrane in most glomeruli. Electron microscopy disclosed the splitting glomerular basement membrane and scattered electron-dense deposits.

Tight junctions in the rat parotid gland

The aim of this study was to elucidate the distribution and morphological changes of tight junctions during secretion in parotid gland acinar cells. Localization of tight junction-associated polypeptide ZO-1, and of tight junction transmembrane protein Occludin, was examined in rat parotid gland by immunofluorescence and immunogold labelling of ultrathin sections. Adult male Sprague-Dawley rats were intraperitoneally injected with IPR and, after 10 and 30 minutes, parotid glands were extirpated. In control specimens, positive immunoreaction for ZO-1 and Occludin was observed on the adluminal side between adjacent cells in the form of narrow elongated profiles corresponding to intercellular canaliculi. After IPR injection, canaliculi became dilated and fluorescence was no longer seen as a continuous line but appeared as an aggregation of separate bright particles. ZO-1 was more widely distributed and was recognized in other areas of the cytoplasm as well. Concurrently, omega-shaped concavities, marked by actin fluorescence, appeared along the intercellular canaliculi. We concluded that, during exocytosis, the selective permeability barrier to the paracellular pathway, based on tight junctions, becomes more leaky, owing to segregation of Occludin caused by intracellular ZO-1 distributional changes associated with actin filaments.

Ultrastructure of collagen fibers in the outer membrane of recurrent chronic subdural hematoma

The three-dimensional structure of the collagen fibers in the outer membrane of recurrent chronic subdural hematoma was studied by scanning electron microscopy (SEM). Specimens obtained at surgery were treated with NaOH at room temperature to digest away all cellular components and expose the collagen fibers. SEM observation of the dural side of the outer membrane showed the collagen fibers were woven into a compact feltwork with a dense arrangement. The fiber bundles had a honeycomb structure framed by the collagen fibers. Observation of the hematoma side found the collagen bundles had a sparse wavy appearance. The arrangement of the collagen fibers on the dural side is different from that on the hematoma side. The thick outer membrane may be formed by granulation resulting from inflammatory reaction. Collagen fibrillar networks are not fragile, and may reinforce the outer membrane of the recurrent hematoma.

Risk of surgical glove perforation in oral and maxillofacial surgery

Oral and maxillofacial surgery, which involves several sharp instruments and fixation materials, is consistently at a high risk for cross-contamination due to perforated gloves, but it is unclear how often such perforations occur. This study aimed to address this issue. The frequency of the perforation of surgical gloves (n=1436) in 150 oral and maxillofacial surgeries including orthognathic surgery (n=45) was assessed by the hydroinsufflation technique. Orthognathic surgery had the highest perforation rate in at least 1 glove in 1 operation (91.1%), followed by cleft lip and palate surgery (55.0%), excision of oral soft tumour (54.5%) and dental implantation (50.0%). The perforation rate in scrub nurses was 63.4%, followed by 44.4% in surgeons and first assistants, and 16.3% in second assistants. The odds ratio for the perforation rate in orthognathic surgery versus other surgeries was 16.0 (95% confidence interval: 5.3-48.0). The protection rate offered by double gloving in orthognathic surgery was 95.2%. These results suggest that, regardless of the surgical duration and blood loss in all fields of surgery, orthognathic surgery must be categorized in the highest risk group for glove perforation, following gynaecological and open lung surgery, due to the involvement of sharp objects.