Search

The aim of the present experiment was to compare the data on new bone formation measured histologically and microtomographically in maxillary sinuses augmented with a xenograft with higher density and higher mineral content compared with the natural bone. The hypothesis was that histomorphometric and micro-computed tomography (microCT) analyses do not yield similar outcomes when a xenograft with higher density and mineral content compared with the natural bone is used. In 18 rabbits, the maxillary sinus was augmented bilaterally using deproteinized bovine bone mineral (DBBM) xenograft granules of either 0.125–1 mm or 1–2 mm of dimensions. The rabbits were euthanized after 2, 4, and 8 weeks of healing. Comparisons were performed between microCT and histological analyses. After 2 weeks of healing, higher contents of bone were found at the histological compared with the microCT analyses in both sinuses, especially in the middle regions of the grafted sinus. Between 2 and 8 weeks of healing, new bone increased of about 21% at the histological analyses while, at the microCT, increased only about 4%. In the same period, the xenograft proportion decreased from 51.6 ± 4.9 to 45.3 ± 3.3% at the histological analyses while, at the microCT, the xenograft appeared to increase in percentages. Histological and microCT analyses yielded different outcomes when a xenograft with higher density and higher mineral content compared with the natural bone was used.

Objective Plasma of argon treatment was demonstrated to increase material surface energy leading to stronger and faster interaction with cells. The aim of the present in vitro study was to test the effect of plasma treatment on different graft materials. Materials and methods Synthetic hydroxyapatite (Mg-HA), biphasic calcium phosphate (BCP), cancellous and cortical xenogeneic bone matrices (CaBM, CoBM) were used representing commonly used classes of bone substitute materials. Fifty serially numbered disks with a 10 mm-diameter from each graft material were randomly divided into two groups: test group (argon plasma treatment) and control group (absence of treatment). Cell morphology (using pre-osteoblastic murine cells) and protein adsorption were analyzed at all samples from both the test and control group. Differences between groups were analyzed using the Mann–Whitney test setting the level of significance at p Results Plasma treatment significantly increased the protein adsorption at all samples. Similarly, plasma treatment significantly increased cell adhesion in all groups. Conclusions Data confirmed that non-atmospheric plasma of argon treatment led to an increase of protein adsorption and cell adhesion in all groups of graft material to a similar extent. Clinical relevance Plasma of argon is able to improve the surface conditions of graft materials.

Summary Background Infective endocarditis (IE) is known to be a life-threatening disease and invasive dental procedures are considered to be important factors. Oral amoxicillin (AMPC) is widely used for prophylaxis in patients with heart disorders who are at risk for IE. However, there is only limited information regarding the inhibition of oral bacteria by AMPC. Methods and results Dental plaque specimens were obtained from 120 healthy Japanese adult subjects, then diluted and streaked onto selective medium for oral streptococci. The minimum inhibitory concentration (MIC) of AMPC was evaluated using a macro-dilution method by Clinical Laboratory Standard Institute (2006). Seven strains with an MIC of AMPC of 16 μg/mL or more were isolated from 5 subjects. The bacterial species were confirmed by sequence analysis of 16S rRNA from each strain, which demonstrated that most were Streptococcus sanguinis, followed by Streptococcus oralis. Dental plaque specimens collected from these 5 subjects again after an interval of 2–3 months possessed no strains with an MIC of AMPC of 16 μg/mL or more. Conclusions These findings suggest that strains with a high MIC of AMPC are present in the oral cavities of Japanese adults, though they may be transient rather than inhabitants.

Cerebral gigantism is an overgrowth disorder that occurs from the prenatal stage through childhood and features such clinical symptoms as advanced bone age, macrocephaly, characteristic facial appearance, and learning difficulties. A 4-year 3-month-old girl was referred to our clinic for consultation regarding anterior crossbite and occlusal pain in the molar region. An intraoral examination showed that the mandible was considerably larger than the maxilla. The dental age of the entire dentition estimated from orthopantomogram images was approximately 1 year ahead of chronological age. Cephalometrics analysis demonstrated maxillary protrusion, prominent mandibular protrusion, and vertically severe short face. The size of maxilla was slightly small, whereas that of mandible was above the average. Since height and body weight were above the 97 percentile, the patient was referred to a pediatrician for a general examination prior to dental treatment and diagnosed with suspected cerebral gigantism. As for occlusal pain in the molar region, we considered that it was caused by excessive occlusal pressure. Following application of splinting and several adjustments, the pain gradually disappeared.

Oral streptococci are major pathogens of infective endocarditis. Prophylactic antibiotics are commonly given to subjects with certain kinds of heart disorders when invasive dental treatments are performed, with amoxicillin (AMPC) being widely used for this purpose. However, there is little information regarding AMPC-resistant oral streptococci. Here, a total of 344 dental plaque specimens collected from 253 healthy Japanese children, adolescents and young adults (aged 2–22 years) were diluted and streaked onto culture medium containing high-dose AMPC. The MICs for the isolated strains were evaluated using a macrodilution broth method described by the Clinical and Laboratory Standards Institute. Bacterial DNA was extracted from each strain and the entire sequences of the 16S rRNA gene were compared with those in GenBank to identify the species. The results showed that strains with AMPC MICs >16 µg ml−1 were isolated from 18 specimens from 14 patients. Analyses of the 16S rRNA gene sequences of these strains identified them as major oral streptococcal species, including Streptococcus oralis and Streptococcus mitis. These findings indicate that oral streptococci with elevated MICs for AMPC exist in certain small populations of healthy children, and highlight the need for further studies to determine risk factors that lead to the appearance of such strains.

Although several risk factors for stroke have been identified, one-third remain unexplained. Here we show that infection with Streptococcus mutans expressing collagen-binding protein (CBP) is a potential risk factor for haemorrhagic stroke. Infection with serotype k S. mutans, but not a standard strain, aggravates cerebral haemorrhage in mice. Serotype k S. mutans accumulates in the damaged, but not the contralateral hemisphere, indicating an interaction of bacteria with injured blood vessels. The most important factor for high-virulence is expression of CBP, which is a common property of most serotype k strains. The detection frequency of CBP-expressing S. mutans in haemorrhagic stroke patients is significantly higher than in control subjects. Strains isolated from haemorrhagic stroke patients aggravate haemorrhage in a mouse model, indicating that they are haemorrhagic stroke-associated. Administration of recombinant CBP causes aggravation of haemorrhage. Our data suggest that CBP of S. mutans is directly involved in haemorrhagic stroke., The risk factors associated with both ischemic and haemorrhagic stroke are not fully understood. Here a certain strain of the bacteria, Streptococcus mutans, which expresses a collagen-binding protein, is shown to be associated with haemorrhagic stroke in both animal models and human patients.

A case of duodenal varices successfully treated by a systemic obliteration of the varices, which has been employed at the department, is reported with a review of the Japanese literature. A 52-year-old woman was admitted to the hospital because of tarry stool. An upper gastrointestinal endoscopy showed an enlarged and tortuous varices with redness in the second portion of the duodenum. Transileocolic vein portgraphy revealed collateral veins composed of the supperior and inferior pancreaticoduodenal veins. From these findings a diagnosis of duodenal varices was made, and a systemic obliteration of varices which composed of an embolization by coils and endoscopic embolization was performed. After that, endoscopical examination revealed that morphology of the varices was improved but the redness persisted. Endoscopic obliteration was carried out two times. No recurrence of the varices has been observed during the follow up period of two years after the treatment. Duodenal varix is rare and the etiology mainly attributable to portal hypertension. It can cause gastrointestinal bleeding. A systemic obliteration of the collateral veins, which has been employed for esophageal varices at the department, was useful.

The author proposes a new technique for adhering papers for conservation procedures: micro-dot adhesion. Adhering is one of the key techniques in p"lper conservation. In some cases, waterbased adhesives such as natural starch paste and synthetic methyl cellulose cause trouble with water-sensitive materials. The micro-dot application of paste provides a minimal quantity of the paste. (The percentage amount of paste is roughly estimated from comparison with a graphic designer's screen: it might be 5% or less of the entire surface.) As a result, the paste stays on the surface and hardly penetrates inside. These facts allow water-based paste to be applied to water-sensitive materials for adhering. This is a very useful advantage for practical conservation work. Conventional starch paste, methyl cellulose and hydroxypropyl cellulose in water can be used. Another advantage is that it minimizes drying time, shrinkage and distortion and prevents the adhered papers becoming hard and solid. Furthermore, it offers easier detaching of the adhered papers. Water is not necessary for removing adhered paper, and inserting a thin spatula will be enough to detach the papers. It means that micro-dot adhesion is an easier, reversible method for paper conservation. Application of the paste can be done by various kinds of printing technique such as an offset technique with letterpress and a stencil technique. An ink-blotter has good shape and structure as an applicator for the paste. Instead of blotting paper, a net covers the bottom surface. The net surface of the blotter picks up paste from the table on which the paste has previously been applied flat. For offsetting, the blotter is then rolled on a paper that is to be used for mending. The paste is transferred to the paper from the net in dots and it is ready to use. For rather larger paper, a stencil is useful. A stencil paper having tiny holes, fixed on a frame at its edges, is used for application of the paste just as it is used for silkscreen printing. A larger amount of paste can be applied through the thickness of the stencil paper. The fluffed-up surface of Japanese paper is used for soft and flexible lining. Japanese paper is easily fluffed up by brushing the surface with a hard brush. The paste is applied on top of the fluffed-up fibres by an offset technique. First the paste is applied on a board, and the fluffed-up paper is then gently laid down on the pasted board. One soft brushing is enough to offset the paste to the top of the fibres. The technique is effective in the case of pasting a hinge-paper tip for matting a print. Sometimes an original print can show partial distortion caused by pasting hinge-paper at the corners. The micro-dots do not need much paste, so the pasted part does not contract as much as in the conventional method, because the paste is applied individually in tiny dots and there are many spaces between the dots. The usual, conventional way of pasting a sheet of paper, large or small, has been flat application by brush, even though the consistency of the paste is controlled. To repair a tear in the page of a Japanese book from the eighteenth/nineteenth century, thinly diluted paste is used to prevent the repaired part becoming hard. But thin paste can easily penetrate too much; blotting paper has to be inserted to dry it and to prevent bleeding to the next pages and shrinkage. Drying takes time. The dot-pasted mending paper is first put in a gutter-shaped paper carrier, and the carrier is inserted between the pages. Then the page is lightly pressed and the cmTier is withdrawn, leaving the mending paper. The mending paper does not adhere as strongly as in the conventional method. But such strong adhesion is not needed, because the book is handled carefully in a mu~eum collection and not treated as it was in private, everyday use. Advantages of the micro-dot technique

As a result of study on the NOx formation choracteristics of pre-mixed flames, we have succeeded in developing new low NOx berners. These burners can be used for various kinds of chemical furnaces as gas and/or oil firing burners with a natural draft system.According to the results of test of these burners in the semicommercialized scale test furnace, their NOx emissions were very small, being 30 ppm in propane or naphtha firing, 45 ppm in A heavy oil firing and 90 ppm in C heavy oil firing (of the time of combustion of 5% excess O2)

The aim of this article is to investigate algebraic nature of systems of one-valued mappings of given group into given field and to apply it to the theory of Galois algebras and duality of compact T0-groups. The results obtained in the following are those; factor systems of Galois algebras with finite Galois groups are defined without any restrictions on the orders of Galois groups and the coefficient fields, a necessary and sufficient condition for them to be associated with Galois fields is obtained, dualities of finite groups are obtained very simply without any restrictions for coefficient field of representations, and Tannaka’s duality of compact T0-groups is proved without the use of the compactness of Tannaka representation groups of representations of compact T- groups and the use of Kampen’s theorem.

Let k be an algebraic number field of finite degree or an algebraic function field of dimension 1 with finite constant field and let K/k be a finite, separably Galois extension field. We call an algebraic extension field L, not necessarily Galois nor necessarily of finite degree, of K an everywhere locally abelian extension, denoted in the following as EL-abelian extension, for brevity, of K over k, if and only if for every finite extension L' of K in L and every valuation v of L it holds that the completion field Lv' of L' with reference to v is a composition field of KV and an abelian extension Mv of kv in Lv', where we denote by kv and KV the closures of k and K in Lv', respectively. Let Q be an algebraic closure of K, BK/k the maximum separably EL-abelian extension of K/k in Q, CK/k the maximum separably central extension of K/k in Q (i.e. the maximum extension CK/k which is separably normal over k, contains K, and has the Galois group of CK/k/K in the center of the Galois group of CK/k/k), Ik and IK the groups of the ideles of k and K, Ak and AK the maximum separably abelian extensions of k and K in Q, respectively. Let DK/k=BK/k nCKIk. Then, the norm residue symbol 0Jk in Ak/k is, if restricted into NK/kIK, extensible into a homomorphism UK/k of NK/kIK into the Galois group G(DK/k/K). We shall study in the present article arithmetical meanings of the extensibility. In ?1, we shall define oUK/k precisely, in ?2, study the kernel and obtain a principal genus theorem (Theorem 2), from which will follow easily a certain generalized formulation of some fundamental theorems in the class field theory.1 Combining it with a known property2 of the quotient group of the connected component of the unit element of the idele class group by the natural image of the maximal compact subgroup of the connected component of the unit element of the idele group, we shall obtain, in ?3, our main result (Theorem 8), which concerns total norm residues in the principal idele group of k for K/k, and which is, the author thinks, an idele-theoretic reconstruction of a research of Scholz.3

Recently Prof. Chevalley in Nagoya suggested to the author the following problem: Let k be a field, K5 = k(x1, x2, x3, x4, x5) be a purely transcendental extension field (of transcendental degree 5) of k, s5 be the cyclic permutation of x: S5X1 = x2s5x2 = x3s5x3 = x4s5x4 = x5s5x5 = x1, and let L5 be the field of invariants of s5 in K5. Is L5 then purely transcendental over k or not? When the characteristic p of k is not equal to 5, it is answered in the following positively. When the characteristic p of k is equal to 5, it is answered also positively by Mr. Kuniyoshi’s result in [2].