A potential role for the silent information regulator 2 homologue 1 (SIRT1) in periapical periodontitis.

AIM: To investigate the role played by silent information regulator 2 homologue 1 (SIRT1) during angiogenesis of periapical periodontitis. METHODOLOGY: Periapical granulomas were subjected to dual-colour immunofluorescence imaging and real-time polymerase chain reactions assaying the expression levels of SIRT1, vascular endothelial growth factor (VEGF) and VE-cadherin. The association between Ki-67 and SIRT1 expression was also examined. Human umbilical vein endothelial cells (HUVECs) were treated with a combination of lipopolysaccharide and resveratrol (a SIRT1 activator) or sirtinol (a SIRT1 inhibitor); and the levels of mRNAs encoding SIRT1, VEGF and VE-cadherin were determined. HUVEC tube formation was assayed in the presence of resveratrol or sirtinol. The Mann-Whitney U-test or the Tukey-Kramer test was used for statistical analysis. RESULTS: Ki-67-expressing cells, including endothelial cells, lay adjacent to SIRT1-expressing cells in periapical granulomas. In addition, SIRT1-expressing cells were detected adjacent to VEGF-expressing cells and VEGF- or VE-cadherin-expressing endothelial cells. SIRT1, VEGF and VE-cadherin mRNA expression levels in periapical granulomas were significantly higher (P = 0.0054, 0.0090 and 0.0090, respectively) than those in healthy gingival tissues. HUVECs treated with resveratrol exhibited significantly higher expression of mRNAs encoding SIRT1, VEGF and VE-cadherin (P = 0.0019, 0.00005 and 0.0045, respectively) compared with controls, but sirtinol inhibited such expression. Resveratrol caused HUVECs to form tube-like structures, whilst sirtinol inhibited this process. CONCLUSIONS: These findings suggest that SIRT1 may stimulate angiogenesis in periapical granulomas by triggering the proliferation of endothelial cells and inducing VEGF and VE-cadherin expression.

Change in oral health status associated with menopause in Japanese dental hygienists.

OBJECTIVES: Oral symptoms such as xerostomia and burning mouth syndrome have been recognized to increase associated with menopause. The purpose of this study was to clarify the changes in oral health as well as systemic health due to menopause and their relations with hormonal change and mental status. METHODS: Ninety-seven female dental hygienists aged 40-59 years were assigned to premenopausal, menopausal and post-menopausal groups based on self-reported menstrual condition. Subjective health statuses were evaluated by questionnaire, and objective holistic and oral statuses were evaluated by measuring serum 17ß-estradiol (E2), salivary flow rate, α-amylase and secretory IgA (SIgA) and taste sensitivity. RESULTS: A significant difference among the three groups was observed in the self-rating questionnaire of depression (SRQ-D) score and serum E2 level as well as unstimulated salivary flow rate, whereas no significant difference was observed in Simplified menopausal index, Short-Form 36-Item Health Survey, General Oral Health Assessment Index, salivary α-amylase activity, salivary SIgA concentration and taste threshold. Serum E2 levels positively correlated with unstimulated salivary flow rates and negatively correlated with SRQ-D scores and α-amylase activities. CONCLUSIONS: The results demonstrated a negative correlation between E2 levels and SRQ-D scores as well as salivary α-amylase activities, suggesting an influence of E2 on mental condition. Furthermore, E2 decrease may result in reduction of salivary flow which in turn causes various problems of oral health. Since the participants were graduates from several dental hygienist schools and working at various places, these results can be generalized to Japanese dental hygienists to some extent.

Comparison of two types of ulnar component in type-5 Kudo total elbow arthroplasty in patients with rheumatoid arthritis: a long-term follow-up.

The purpose of this study was to assess the long-term results (more than ten years) of two types of cemented ulnar component with type-5 Kudo total elbow arthroplasty in a consecutive series of 56 patients (60 elbows) with rheumatoid arthritis, and to compare the results in elbows above and below a Larsen grade IV. There was no radiolucency around the humeral component. Patients in whom a metal-backed ulnar component and a porous-coated stem were used had better clinical results and significantly less progression of radiolucent line formation around the ulnar component. They also had a significantly better long-term survival than patients with an all-polyethylene ulnar component. The clinical results of arthroplasty using all-polyethylene ulnar components were inferior, regardless of the degree of joint destruction. We conclude that the type-5 Kudo total elbow arthroplasty with cementless fixation of the porous-coated humeral component and cemented fixation of a metal-backed ulnar component is acceptable and well-tolerated by rheumatoid patients.

An improved phase shift reconstruction algorithm of fringe scanning technique for X-ray microscopy.

The X-ray phase imaging method has been applied to observe soft biological tissues, and it is possible to image the soft tissues by using the benefit of the so-called "Talbot effect" by an X-ray grating. One type of the X-ray phase imaging method was reported by combining an X-ray imaging microscope equipped by a Fresnel zone plate with a phase grating. Using the fringe scanning technique, a high-precision phase shift image could be obtained by displacing the grating step by step and measuring dozens of sample images. The number of the images was selected to reduce the error caused by the non-sinusoidal component of the Talbot self-image at the imaging plane. A larger number suppressed the error more but increased radiation exposure and required higher mechanical stability of equipment. In this paper, we analyze the approximation error of fringe scanning technique for the X-ray microscopy which uses just one grating and proposes an improved algorithm. We compute the approximation error by iteration and substitute that into the process of reconstruction of phase shift. This procedure will suppress the error even with few sample images. The results of simulation experiments show that the precision of phase shift image reconstructed by the proposed algorithm with 4 sample images is almost the same as that reconstructed by the conventional algorithm with 40 sample images. We also have succeeded in the experiment with real data.

Degradation of benzyl ether bonds of lignin by ruminal microbes.

We examined microbial activity in the rumen to cleave benzyl ether bonds of lignin model compounds that fluoresced when the bonds were cleaved. 4-Methylumbelliferone veratryl ether dimer was degraded completely within 8 h even in the presence of fungicidal antibiotics, but no significant degradation occurred with bactericidal antibiotics. Degradation of a phenolic beta-O-4 trimer incorporating 4-methylumbelliferone by a benzyl ether linkage was stimulated by ruminal microbes, although its corresponding non-phenolic model compound, 1-(4-ethoxy-3-methoxyphenyl)-1-O-(4-methylumbelliferyl)-2-(2-methoxyp henoxy)-3-propanol, was not degraded. A coniferyl dehydrogenation polymer bearing fluorescent beta-O-4 benzyl ether that contains both phenolic and non-phenolic benzyl ether bonds was partially degraded (about 20%) in 48 h. These results suggest that ruminal microbes decompose benzyl ether linkages of lignin polymers under anaerobic conditions.

Total elbow arthroplasty with use of a nonconstrained humeral component inserted without cement in patients who have rheumatoid arthritis.

BACKGROUND: Most total elbow prostheses that are currently in use require cement for fixation of each component. We developed a new (type-5) prosthesis that does not need cement for fixation. METHODS: The humeral component is made of cobalt-chromium alloy, and its stem is porous-coated with a plasma spray of titanium alloy. There are two options for the ulnar component: an all-polyethylene type and a metal-backed type with a porous-coated stem. Forty-three elbows in thirty-seven patients who had rheumatoid arthritis were treated with total elbow replacement arthroplasty with use of the type-5 prosthesis. The humeral component was implanted without cement in all elbows, whereas the ulnar component was implanted without cement in eleven elbows and was fixed with cement in the remaining thirty-two. The elbows were followed for an average of three years and ten months (range, two years and six months to five years and six months). RESULTS: The clinical results were assessed according to a modification of the Mayo Clinic Performance Index. At the time of the latest follow-up, the overall result was excellent for six elbows, good for thirty-one, and fair for six. All elbows had been rated as poor before the operation. There was almost complete relief of pain in twenty-nine elbows and mild or occasional pain in the remaining fourteen. Flexion increased markedly, from an average of 104 degrees preoperatively to an average of 133 degrees postoperatively; this difference was highly significant (p < 0.001, Student t test). In contrast, extension (flexion contracture) worsened slightly, from an average of 38 degrees preoperatively to an average of 42 degrees postoperatively; this difference was significant (p < 0.05). There was one postoperative dislocation of the elbow, and ectopic bone formed in another, with recurrence of ankylosis. Both elbows had a reoperation, and a good result eventually was obtained. There were no instances of postoperative infection or neuropathy of the ulnar nerve. Radiographically, there were no radiolucent lines at the bone-metal interface of any of the humeral or ulnar stems that had been implanted without cement, suggesting solid fixation by osseointegration. CONCLUSIONS: The results of total elbow arthroplasty with use of this prosthesis appear promising. There was a high rate of relief of pain as well as of restoration of adequate function in patients in whom the elbow was severely affected by rheumatoid arthritis.

Non-constrained elbow arthroplasty for mutilans deformity in rheumatoid arthritis: a report of six cases.

Six highly unstable elbows with severe bone loss due to rheumatoid arthritis were replaced by a non-constrained, unlinked prosthesis. Bone defects were filled with autogenous bone grafts. The mean follow-up was 4.5 years (2 to 8). The clinical results were excellent in four elbows and good in two, with good varus-valgus stability in all. Radiological follow-up showed no appreciable signs of loosening, and the bone grafts had retained most of their original size, with minimal resorption. There were no major complications such as dislocation, skin necrosis, infection or ulnar neuropathy. The study has shown that the so-called mutilans elbow can be successfully replaced using a properly selected type of non-constrained, unlinked prosthesis with bone grafting of the major defects.

Polypropylene mesh substitute for the fascial defect after using for the dural repair--technical note.

Use of the anterior sheath of the rectus abdominis muscle (anterior sheath) as a dural substitute and patching of the large defect of the anterior sheath with polypropylene mesh are described. Five patients were treated using the anterior sheath and the mesh. No postoperative complications such as cerebrospinal fluid leakage, infection, or abdominal wall hernia occurred. The mesh is useful as a patch for the sheath defect.

Cause of closed suction drainage tube obstruction and its prevention using a tube coated on the inside with a silicone gel drug delivery system.

In experimental and clinical studies we showed that obstruction of closed suction drainage tubes is often caused by clots. To prevent this we describe a tube coated on the inside with a silicone gel drug delivery system, which releases anticoagulant drugs. It prevents coagulation and liquefies blood clots present in the tube. This device should thus find application as a tube for continuous suction drainage systems.

Interactions between Treponema bryantii and cellulolytic bacteria in the in vitro degradation of straw cellulose.

To assess the contribution of individual bacterial species to the overall process of cellulose digestion in the rumen, cellulolytic bacteria (Bacteroides succinogenes and Ruminococcus albus) were tested as pure cultures and as cocultures with noncellulolytic Treponema bryantii. In studies of in vitro barley straw digestion, Treponema cocultures surpassed pure cultures of the cellulolytic organisms in dry matter disappearance, volatile fatty acid generation, and in the production of succinic acid, lactic acid, and ethanol. Morphological examination, by electron microscopy, showed that cells of T. bryantii associate with the plant cell wall materials in straw, but that cellulose digestion occurs only when these organisms are present with cellulolytic species such as B. succinogenes. These results show that cellulolytic bacteria interact with noncellulolytic Treponema to promote the digestion of cellulosic materials.

Electron microscopic study of the methylcellulose-mediated detachment of cellulolytic rumen bacteria from cellulose fibers.

The presence of methylcellulose prevents the attachment of cellulolytic rumen bacteria to cellulose fibers. The addition of methylcellulose to pure cultures of these organisms in which the cells are already adherent to cellulose causes their detachment from this insoluble substrate and the inhibition of their growth. Methylcellulose is not used as a carbon source by these organisms and has no effect on their growth when glucose and cellobiose are the carbon sources. Attached cells of Bacteroides succinogenes orient themselves in the plane of the individual cellulose fibers and their methylcellulose-induced detachment, which is complete (almost 100%), leaves grooves where the cellulose has been digested. Attached cells of Ruminococcus albus colonize the cellulose in a looser and less regular pattern and their almost complete methylcellulose-induced detachment leaves less regular pits in the cellulose surface. On the other hand, attached cells of Ruminococcus flavefaciens colonize the cellulose surface in a random orientation by means of a discernible exopolysaccharide network, and their less complete methylcellulose-induced detachment leaves no residual impressions on the cellulose surface. These data support the suggestion that bacterial attachment is necessary for the digestion of highly ordered crystalline cellulose, and that cellulolytic species differ in the nature of their attachment to this insoluble substrate and in the nature of their enzymatic attack. Methylcellulose is an effective agent for detaching major rumen cellulolytic bacteria from their cellulosic substrate.

Side-effects of prosthetic materials on the human body.

The authors report 6 patients (7 joints) in whom inflammation, dermal necrosis, dermatitis or fistula formation was attributed to the materials commonly used for joint endoprostheses. Histological appearances and chemical analyses of the involved tissues are presented, together with a discussion of the possible mechanism and methods of diagnosis and treatment.

Contact dermatitis from a compound mixture of sugar and povidone-iodine.

2 patients with leg ulcers got worse after the application of a compound mixture of sugar and povidone-iodine (sugar/PI compound). Because they had been suffering from stasis dermatitis, symptoms of contact dermatitis were ambiguous. Patch tests showed positive reactions to 10% povidone-iodine in water and 5% potassium iodide in water, with no response to sugar. They were also tested with sugar/PI compound, containing 3% povidone-iodine, resulting in another positive reaction. They improved after the application of sugar/PI compound was discontinued. Contact dermatitis from topical agents should be considered as more probable than angry back syndrome in cases of leg ulcer.

Isolation and characterization of cellulolytic anaerobic fungi and associated mycoplasmas from the rumen of a steer fed a roughage diet.

The isolation of 12 strains of cellulolytic fungi from the rumen of a roughage-fed steer is described. These represented three different genera, including one new genus and species (Orpinomyces bovis). The organisms were indistinguishable on the basis of fermentation products from cellulose, and their fermentation patterns were very similar to those of rumen fungi isolated in other countries. Mycoplasmas were found to be associated with 7 of the 12 isolates. The ecological role of the association of the mycoplasmas with rumen fungi is still unknown.

Food intake, nutrient utilization and water turnover in the lesser mouse-deer (Tragulus javanicus) given lundai (Sapium baccatum).

Voluntary food intake, digestibility and water turnover were determined in adult Malaysian lesser mouse-deer (Tragulus javanicus) given unlimited access to lundai foliage (Sapium baccatum). Daily dry matter (DM) intake was 42.4 g/kg metabolic live mass (M0.73) or 3.7% M. Digestible energy intake was 853 kJ/day (571 kJ metabolisable energy per M0.73), calculated to be used with 79% efficiency. Apparent digestibility (%) of organic matter was 83.8, crude fibre 63.7, acid detergent fibre 60.5, neutral detergent fibre 72.1 and crude protein 65.0. Urinary excretion of the purine derivative, allantoin, was 0.05 mg/g digestible DM intake suggesting rumen microbial yield efficiency may be lower than in other ruminant species. Total water intake was 182 ml/M0.82. The body-water content of the fed mouse-deer, from tritiated water dilution, was 77% M, consistent with a very lean carcass. Turnover of body water was 17% per day. The mouse-deer produced relatively dry, well-defined faecal pellets.

In vivo evaluation of a novel alginate dressing.

Alginate dressings are currently used in the management of epidermal and dermal wounds, and provide a moist environment that leads to rapid granulation and reepithelialization. However, a cytotoxic effect on proliferation of fibroblasts and residual material with inflammation in healing wounds have been reported recently. We have developed a new alginate dressing (AGA-100), which does not have an inhibitory effect on proliferation of fibroblasts. The purpose of this study was to evaluate the new alginate dressing with respect to wound healing in full- and partial-thickness pig wounds and with respect to biodegradation following implantation into rabbit muscle. Kaltostat and Sorbsan, both well-established commercial dressings, were used as control. The closure rate of full-thickness wounds treated with AGA-100 was significantly higher on day 15 compared with that with Kaltostat and Sorbsan. Reepithelialization rate of partial-thickness wounds treated with Sorbsan was statistically significantly lower on day 3 than those with the other two dressings. As to dressing debris remained in the healing wound, a large amount of foreign debris was noted in all the full-thickness wounds treated with Kaltostat or Sorbsan, while only about one-third of wounds treated with AGA-100 showed a little dressing debris. AGA-100 implanted into the muscle of rabbits was bioresorbed completely within 3 months. Therefore, dressing residue in AGA-100-treated full-thickness wounds might be fully absorbed in a few months. In conclusion, it is shown that our newly developed AGA-100 possesses superior properties compared with typical alginate dressings.

The conformational study of chitin and chitosan oligomers in solution.

The inter-residual dihedral angles phi and phip of chitin and chitosan oligomers were determined from experimental 3J(C-H) constants and ROESY cross peaks.

Prevention of fungal colonization and digestion of cellulose by the addition of methylcellulose.

When the attachment of cellulolytic rumen fungi to cellulose is blocked by the addition of methylcellulose, cellulose digestion is entirely inhibited. Even after these fungi have colonized and penetrated the cellulosic fibers of filter paper, the addition of methylcellulose effectively halts cellulose digestion. This effect of methylcellulose is accompanied by the complete inhibition of fungal attachment to cellulose fibers; the addition of methylcellulose does not affect the growth of these organisms on soluble substrates. We conclude that fungal cellulose digestion, like bacterial cellulose digestion, requires the spatial juxtaposition of the cellulolytic organism and its insoluble substrate. The simultaneous inhibition of both attachment and digestion by the same inhibitor suggests that these two processes are functionally linked in the fungi.