Atomic-scale study of TiO2-GR nanohybrid formation by ALD: the effect of the gas phase precursor

In the present work, we report on a theoretical-computational study of the growth mechanism of the TiO2-Graphene nanohybrid by atomic layer deposition. Hydroxyl groups (OH) are anchoring sites for interacting with the main ALD titanium precursors (Tetrakis (dimethylamino) Titanium, Titanium Tetrachloride, and Titanium Isopropoxide). Results demonstrate that the chemical nature of the precursor directly affects the reaction mechanism in each ALD growth step. Tetrakis(dimethylamino)titanium is the precursor that presents a higher affinity (lower energy barriers for the reaction) to hydroxylated graphene in the growth process. A complete reaction mechanism for each precursor was proposed. The differences between precursors were discussed through the non-covalent interactions index. Finally, the water molecules help reduce the energy barriers and consequently favor the formation of the TiO2-graphene nanohybrid.

Atomic-scale visualization of topological spin textures in the chiral magnet MnGe

[Figure: see text].

Conceptualizing the origin of life in terms of evolution

In this opinion piece, we discuss how to place evolution in the context of origin-of-life research. Our discussion starts with a popular definition: 'life is a self-sustained chemical system capable of undergoing Darwinian evolution'. According to this definition, the origin of life is the same as the origin of evolution: evolution is the 'end' of the origin of life. This perspective, however, has a limitation, in that the ability of evolution in and of itself is insufficient to explain the origin of life as we know it, as indicated by Spiegelman's and Lincoln and Joyce's experiments. This limitation provokes a crucial question: What conditions are required for replicating systems to evolve into life? From this perspective, the origin of life includes the emergence of life through evolution: evolution is a 'means' of the origin of life. After reviewing Eigen's pioneering work on this question, we mention our ongoing work suggesting that a key condition might be conflicting multi-level evolution. Taken together, there are thus two questions regarding the origin of life: how evolution gets started, and how evolution produces life. Evolution is, therefore, at the centre of the origin of life, where the two lines of enquiry must meet.This article is part of the themed issue 'Reconceptualizing the origins of life'.

Symmetric Peripheral Running Sutures are Superior to Asymmetric Peripheral Running Sutures for Increasing the Tendon Strength in Flexor Tendon Repair

BACKGROUND

The fatigue strength of three peripheral suture techniques for flexor tendon repair was compared by cyclic loading of the repairs in the porcine flexor digitorum tendon.

METHODS

Thirty-six tendons were sutured using only peripheral sutures with 6-0 Nylon. An initial cyclic load of 10 N for 500 cycles was applied and increased by 10 N for an additional 500 cycles at each new load until rupture.

RESULTS

The fatigue strength of the symmetric running peripheral suture was 85.0% and 144.8% greater than that of the two kinds of the asymmetric running peripheral sutures.

CONCLUSIONS

Symmetric running sutures can enhance the suture strength and appears to be a useful technique for increasing the strength of the peripheral suture.

Brodie's Abscess of the Radius in a Child

We herein report an unusual case of Brodie's abscess of the radius in a child. A 13-year-old boy presented with pain on his right distal forearm. A plain radiograph showed an 8 cm translucent lesion in the distal radius. MRI showed a penumbra sign on the T1-weighted image, hyperintensity on T2-weighted images, and ring enhancement on the contrast-enhanced T1 image. ¹⁸F-FDG PET/CT images showed an uptake at the margin of the radius. Curettage and iliac cancellous bone grafting were undertaken for Brodie's abscess. Bacteriological examinations were found to be negative, however, the pathologic diagnosis showed chronic osteomyelitis. Eight months after surgery, the patient was asymptomatic and there was no sign of recurrence of infection. For Brodie's abscess in a child, thorough debridement is mandatory in addition to cancellous bone grafting. Brodie's abscess should be considered in the differential diagnosis of a patient who presents with forearm pain and exhibit the radiolucent osteolytic lesion on simple radiography.

Asymmetric six-strand core sutures enhance tendon fatigue strength and the optimal asymmetry

Under cyclic loading, we recorded the fatigue strength of a six-strand tendon repair with different symmetry in the lengths of suture purchase in two stumps of 120 dental rolls and in 30 porcine tendons. First, the strengths of the repairs with 1, 2, 3, 4 and 5 mm asymmetry were screened using the dental rolls. The asymmetric core suture repairs were then made with a Kessler repair of equal suture purchase (10 mm) in two tendon stumps, and shifting two other Kessler repairs by 1, 3 or 5 mm, respectively, along the longitudinal axis of the tendon in relation to the first (symmetric) Kessler repair. The core repairs with 3 mm or more asymmetry in suture purchases in two tendon ends showed significantly greater fatigue strength and significantly smaller gaps compared with 1 mm asymmetry in core suture repair. Our results support that asymmetric placement of core sutures in two tendon ends favour resisting gapping at the repair site and 3 mm or more asymmetry is needed to produce such beneficial effects.

Spontaneous Pneumothorax Caused by Metastatic Hemangioendothelioma

A patient with hemangioendothelioma is described, who developed a metastatic pulmonary nodule, subsequently a bullous lesion contiguous to the nodule, and finally spontaneous pneumothorax. In such cases, newly formed bullous lesions may conceal originally visible metastatic foci and can be a potential source of spontaneous pneumothorax.

CT Findings of Endobronchial Metastasis

One hundred and sixty-one patients with pulmonary metastases were studied with CT. Six of them proved to have endobronchial (intraluminal) metastatic lesions by bronchoscopy. Retrospective analysis of the CT studies showed obstruction and/or narrowing of the bronchi in 5 cases while no lesion was observed in one patient. Although CT can not always demonstrate intraluminal lesions, it should be performed when an endobronchial metastasis from extrathoracic malignancy is seen by bronchoscopy because it will show hilar or mediastinal lymphadenopathy, or single or multiple pulmonary metastases other than the endobronchial lesion.

Computed Tomography and Ultrasonography in Parotid Tumors

To determine the most appropriate radiographic approach to parotid tumors, computed tomography (CT) was performed in 65 patients with 33 benign tumors, 19 malignant tumors, 3 abscesses and 10 other lesions with a clinical appearance of tumor. In 22 of the 65 cases CT-sialography and in 26 ultrasonography (US) were also performed. The mass was well recognized on CT without sialography in all patients, and the lesion was also well evaluated in all those examined with US. At CT-sialography the tumor was well shown, but this method made it difficult to differentiate a benign from a malignant lesion, because the character of the delineation and the border of the tumor were difficult to evaluate. It is concluded that US and CT without sialography are satisfactory for evaluating the parotid tumor, and the indication for CT-sialography is limited to those cases in which the tumor is demonstrated on US, but is unclear on conventional CT.

Healing of localized gingival recessions treated with a coronally advanced flap alone or combined with an enamel matrix derivative and a porcine acellular dermal matrix: a preclinical study

OBJECTIVE

This study aimed to evaluate the effects of a porcine acellular dermal matrix (PADM) with or without an enamel matrix derivative (EMD) on gingival recession defects treated with a coronally advanced flap (CAF) in dogs.

MATERIALS AND METHODS

Miller class II gingival recession defects (5 mm wide and 7 mm deep) were surgically created on the labial side of bilateral maxillary canines in 12 dogs. After 8 weeks of plaque accumulation, the 24 chronic defects were randomly assigned to one of the following 4 treatments: CAF, CAF with PADM (CAF/PADM), CAF with EMD (CAF/EMD), and CAF with EMD and PADM (CAF/EMD/PADM). The animals were sacrificed 10 weeks after surgery for histologic evaluation.

RESULTS

In all groups, root coverage was obtained to a varying degree. PADM was well incorporated in gingival connective tissue in the CAF/PADM and in the CAF/EMD/PADM groups. The height of newly formed bone was significantly greater in the CAF/EMD/PADM group than in the CAF and CAF/PADM groups. New cementum with periodontal ligament-like tissue was predominantly found in the CAF/EMD and CAF/EMD/PADM groups. The CAF/EMD/PADM group showed the greatest amount of new cementum among the groups examined, although the difference was not statistically significant.

CONCLUSION

Within the limitations of the present study, it can be concluded that CAF/EMD/PADM treatment may promote periodontal regeneration in gingival recession defects.

CLINICAL RELEVANCE

The present results suggest that the combination of EMD and PADM in conjunction with CAF may represent a promising approach for treating single Miller class II gingival recessions.

Reversible logic gate using adiabatic superconducting devices

Reversible computing has been studied since Rolf Landauer advanced the argument that has come to be known as Landauer's principle. This principle states that there is no minimum energy dissipation for logic operations in reversible computing, because it is not accompanied by reductions in information entropy. However, until now, no practical reversible logic gates have been demonstrated. One of the problems is that reversible logic gates must be built by using extremely energy-efficient logic devices. Another difficulty is that reversible logic gates must be both logically and physically reversible. Here we propose the first practical reversible logic gate using adiabatic superconducting devices and experimentally demonstrate the logical and physical reversibility of the gate. Additionally, we estimate the energy dissipation of the gate, and discuss the minimum energy dissipation required for reversible logic operations. It is expected that the results of this study will enable reversible computing to move from the theoretical stage into practical usage.

Similar in vitro effects and pulp regeneration in ectopic tooth transplantation by basic fibroblast growth factor and granulocyte-colony stimulating factor

OBJECTIVES

Granulocyte-colony stimulating factor (G-CSF) has been shown to have combinatorial trophic effects with dental pulp stem cells for pulp regeneration. The aim of this investigation is to examine the effects of basic fibroblast growth factor (bFGF) in vitro and in vivo compared with those of G-CSF and to assess the potential utility of bFGF as an alternative to G-CSF for pulp regeneration.

MATERIALS AND METHODS

Five different types of cells were examined in the in vitro effects of bFGF on cell migration, proliferation, anti-apoptosis, neurite outgrowth, angiogenesis, and odontogenesis compared with those of G-CSF. The in vivo regenerative potential of pulp tissue including vasculogenesis and odontoblastic differentiation was also compared using an ectopic tooth transplantation model.

RESULTS

Basic fibroblast growth factor was similar to G-CSF in high migration, proliferation and anti-apoptotic effects and angiogenic and neurite outgrowth stimulatory activities in vitro. There was no significant difference between bFGF and G-CSF in the regenerative potential in vivo.

CONCLUSIONS

The potential utility of bFGF for pulp regeneration is demonstrated as a homing/migration factor similar to the influence of G-CSF.

Speciation in ninespine stickleback: reproductive isolation and phenotypic divergence among cryptic species of Japanese ninespine stickleback

Although similar patterns of phenotypic diversification are often observed in phylogenetically independent lineages, differences in the magnitude and direction of phenotypic divergence have been also observed among independent lineages, even when exposed to the same ecological gradients. The stickleback family is a good model with which to explore the ecological and genetic basis of parallel and nonparallel patterns of phenotypic evolution, because there are a variety of populations and species that are locally adapted to divergent environments. Although the patterns of phenotypic divergence as well as the genetic and ecological mechanisms have been well characterized in threespine sticklebacks, Gasterosteus aculeatus, we know little about the patterns of phenotypic diversification in other stickleback lineages. In eastern Hokkaido, Japan, there are three species of ninespine sticklebacks, Pungitius tymensis and the freshwater type and the brackish-water type of the P. pungitius-P. sinensis species complex. They utilize divergent habitats along coast-stream gradients of rivers. Here, we investigated genetic, ecological and phenotypic divergence among three species of Japanese ninespine sticklebacks. Divergence in trophic morphology and salinity tolerance occurred in the direction predicted by the patterns observed in threespine sticklebacks. However, the patterns of divergence in armour plate were different from those previously found in threespine sticklebacks. Furthermore, the genetic basis of plate variation may differ from that in threespine sticklebacks. Because threespine sticklebacks are well-established model for evolutionary research, the sympatric trio of ninespine sticklebacks will be an invaluable resource for ecological and genetic studies on both common and lineage-specific patterns of phenotypic diversification.

Effects of EMD in combination with bone swaging and calcium phosphate bone cement on periodontal regeneration in one-wall intrabony defects in dogs

BACKGROUND AND OBJECTIVE

Although the application of EMD is a widely accepted periodontal-regenerative therapy, its effects on noncontained intrabony defects are unpredictable because of the lack of a space-making property. The combined use of EMD and autogenous bone grafts reportedly stimulates significant periodontal regeneration in intrabony defects. The aim of the present study was to evaluate the effects of EMD in combination with bone swaging (BS) and injectable calcium phosphate bone cement (CPC), which was placed into the spaces between the grafted swaged bone and the proximal host bone, on periodontal healing in one-wall intrabony defects in dogs.

MATERIAL AND METHODS

One-wall intrabony defects (3 mm wide and 5 mm deep) were surgically created on the mesial and distal sides of the bilateral mandibular premolars in four dogs. The 16 defects were assigned to one of the following treatments: EMD only, BS only, EMD with BS (EMD + BS), or EMD with BS and CPC (EMD + BS + CPC). The animals were killed 8 wk after surgery for histologic evaluation.

RESULTS

The height of newly formed bone was significantly greater in the EMD + BS + CPC group (3.73 ± 0.30 mm) than in the BS-only (2.74 ± 0.33 mm; p < 0.05) and EMD + BS (2.88 ± 0.98 mm; p < 0.05) groups. The area of newly formed bone was significantly larger in the EMD + BS + CPC group (5.68 ± 1.66 mm(2)) than in the EMD-only (3.68 ± 0.33 mm(2); p < 0.05), BS-only (3.48 ± 1.26 mm(2); p < 0.05) and EMD + BS (3.38 ± 1.37 mm(2); p < 0.05) groups. The EMD-only (4.63 ± 0.42 mm), EMD + BS (4.67 ± 0.30 mm) and EMD + BS + CPC (4.78 ± 0.54 mm) groups showed significantly greater cementum formation than did the BS-only group (3.93 ± 0.56 mm; p < 0.05).

CONCLUSION

These results indicate that treatment with EMD + BS + CPC promotes favorable periodontal healing in one-wall intrabony defects in dogs.

The biomechanical assessment of gap formation after flexor tendon repair using partial interlocking cross-stitch peripheral sutures

The gap formation of five core plus peripheral suture techniques for flexor tendon repair was evaluated by cyclic load testing. Fifty pairs of dental roll tendon models were sutured using six-strand Pennington modified Kessler core suture with 4-0 Polypropylene. One-half or three-fourths circumferential interlocking cross-stitch, or three complete circumferential peripheral suture techniques were performed using 6-0 Polypropylene. An initial cyclic load of 10 N for 500 cycles was applied and increased by 5 N for an additional 500 cycles at each new load until rupture. The complete circumferential interlocking cross-stitch had the greatest fatigue strength. The partial circumferential cross-stitches resulted in significantly larger gap formations at both the repaired and unrepaired sides than the complete circumferential sutures, and were also associated with early rupture. The full circumference of the cut tendon must be sutured using an interlocking cross-stitch peripheral suture to improve strength and avoid gap formation.

Relationship between malocclusion and heart rate variability indices in young adults: a pilot study

OBJECTIVES

Heart rate variability (HRV) has been used to assess sympathetic and parasympathetic modulation of heart rate. Chronic stress relates to reduced HRV. Malocclusion has effects on quality of life, which can lead to chronic stress. Therefore, we hypothesized that malocclusion, as chronic stress, may contribute to reduced HRV. The aim of this study was to investigate the relationship between malocclusion and HRV indices in healthy young adults.

METHODS

Thirty-seven non-smoking healthy subjects, aged 22 to 25 years, were examined. Malocclusion was defined by Angle classification. HRV indices included root mean square of successive differences, low frequency (LF), high frequency (HF) and ratio of LF to HF. The effects of malocclusion on quality of life and mental health were assessed using self-reported questionnaires, the condition-specific Oral Impacts on Daily Performances index (CS-OIDP) and the Hopkins Symptoms Checklist (HSCL), respectively.

RESULTS

Significantly lower score of HF and higher heart rate (HR) level and CS-OIDP score were observed in subjects with malocclusion (n = 17) compared to those in the control subjects (n = 20) ( P <0.05). There was a positive correlation between HR and score of "anxiety" in HSCL ( P <0.05).

CONCLUSIONS

The data showed an association between malocclusion and lower HRV. Based on our results, orthodontic treatment might contribute not only to improvement of oral esthetic and functional problems but also to improvement of stress and HRV indices.

On the permeability of the presynaptic terminal of the crayfish neuromuscular junction during synaptic inhibition and the action of gamma-aminobutyric acid

1. The contribution of chloride to presynaptic inhibition of the crayfish neuromuscular junction during the action of gamma-aminobutyric acid (GABA) and the inhibitory transmitter was investigated. Chloride in van Harreveld's solution was replaced with propionate, acetate, methylsulphate or glycerophosphate and electrical changes were recorded intracellularly and extracellularly with micro-electrodes.2. When the preparation was soaked in Cl-deficient solutions, the quantum content of the excitatory junctional potentials (e.j.p.s), calculated from the number of failures, was increased.3. The presynaptic inhibitory action of GABA was reduced or almost absent when the preparation was soaked in Cl-deficient solution. In Cl-deficient solution the stimulation of the inhibitory axon showed little or no inhibitory action on e.j.p.s.4. If GABA was applied shortly after the outside solution was changed to the Cl-deficient one, the frequency of the spontaneous e.j.p.s was increased transiently.5. It is suggested that GABA or the inhibitory transmitter act on the presynaptic excitatory terminal and predominantly increase its permeability to chloride.

Relationship between the prognosis of periodontitis and occlusal force during the maintenance phase--a cohort study

BACKGROUND AND OBJECTIVE

Few studies have longitudinally investigated the relationship between periodontal disease progression and occlusal factors in individual subjects during the maintenance phase of periodontal therapy. The aim of this cohort study was to investigate the relationship between biting ability and the progression of periodontal disease in the maintenance phase.

MATERIAL AND METHODS

A total of 194 patients were monitored for 3 years during the maintenance phase of periodontal therapy. The subjects with disease progression (Progress group) were defined based on the presence of >or= 2 teeth demonstrating a longitudinal loss of proximal attachment of >or= 3 mm or tooth-loss experience as a result of periodontal disease during the study period. The subjects with high occlusal force were diagnosed as men who showed an occlusal force of more than 500 N and women who showed an occlusal force of more than 370 N. The association between biting ability and the progression of periodontitis was investigated using logistic regression analysis.

RESULTS

There were 83 subjects in the Progress group and 111 subjects in the Non-progress group. A backward, stepwise logistic regression model showed that the progression of periodontal disease was significantly associated with the presence of one or more teeth with a high clinical attachment level (CAL) of >or= 7 mm (odds ratio: 2.397; 95% confidence interval: 1.306-4.399) ( p = 0.005) and low occlusal force (odds ratio: 2.352; 95% confidence interval: 1.273-4.346) ( p = 0.006).

CONCLUSION

The presence of one or more teeth with a high CAL of >or= 7 mm and low occlusal force might be possible risk factors for periodontal progression in the maintenance phase of periodontal therapy.

Expression of Tn and sialyl Tn antigens in synovial tissues in rheumatoid arthritis

OBJECTIVES

The carbohydrate chains represented by mucins (MUCs) are expressed by a variety of normal and malignant secretory epithelial cells and induce a variety of immunoreactions. Tn and sialyl Tn antigens are tumour-associated carbohydrate antigens which are borne on the core proteins of mucins. The purpose of this study is to investigate the existence of tumour-associated carbohydrate antigens in rheumatoid arthritis (RA).

METHODS

. We examined the expression of Tn and sialyl Tn antigens in synovial tissues from RA and osteoarthritis (OA) patients by immunohistochemistry. In addition, mucins from synovial fluid (SF) from RA patients are purified by gel filtration and density gradient ultracentrifugation and the existence of these antigens examined by dot and Western blotting.

RESULTS

We found that Tn and sialyl Tn antigens were strongly expressed in synovial cells and infiltrating mononuclear cells on the sublining layer and lymphoid follicles in synovial tissues in RA compared with those in osteoarthritis. Tn and sialyl Tn antigens were detected in purified mucins of SF from RA patients.

CONCLUSIONS

Tumour-like synovial hyperplasia cells expressed Tn and sialyl Tn antigens. This finding suggests that the mucins exhibiting with abnormal glycosylation may be in part responsible for synovial hyperplasia, leading to the joint destruction in the pathogenesis of RA.

Strength enhancement of the interlocking mechanism in cross-stitch peripheral sutures for flexor tendon repair: biomechanical comparisons by cyclic loading

The fatigue strength of three peripheral suture techniques for flexor tendon repair was compared by cyclic loading of repairs in a cotton dental roll tendon model. Thirty pairs of dental roll were sutured using only peripheral sutures with 6-0 polypropylene. An initial cyclic load of 5 N for 500 cycles was applied and increased by 5 N for an additional 500 cycles at each new load until rupture. The fatigue strength of an interlocking cross-stitch suture was 113% greater than a running suture and 36% greater than a standard cross-stitch suture. Interlocking the cross-stitch prevented shortening of the transverse portions under load and appears to be a useful technique for increasing the strength of the peripheral suture.

Comparison of post-translational modifications of alpha A-crystallin from normal and hereditary cataract rats

In order to investigate the relationship between lens opacities and the various modifications of lens proteins, we analyzed and compared the properties of lens proteins of 85-day old normal Wistar rats and the hereditary cataract model, ICR/f rats. The present study identified many differences between normal and mutant lens proteins. In the ICR/f mutant rats, the relative amounts of gamma-crystallin decreased and high molecular weight (HMW) protein increased. Racemization and isomerization of Asp-151 of alpha A-crystallin was observed in the mutant ICR/f rats, and Met-1 of alpha A-crystallin was oxidized to methionine sulfoxide. These modifications were not found in the age-matched normal rats. These tendencies are consistent with aged and cataractous human lenses.