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Introduction: Diagnosing acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) after the first seizure (early seizure/seizures, ES/ESs) is challenging because a reduced apparent diffusion coefficient (ADC) in the cortical or subcortical white matter, often described as having a "bright-tree appearance (BTA)," is usually not observed until secondary seizures (late seizures, LSs) occur. Previous studies have reported hypoperfusion on arterial spin labeling (ASL) within 24 h after ES/ESs in patients with AESD and hyperperfusion within 24 h after LS onset. This study aimed to investigate cerebral blood flow in the hyperacute phase (between ES/ESs and LSs) using ASL in patients with AESD., Methods: Eight ASL images were acquired in six patients with AESD admitted to our hospital from October 2021 to October 2022. ASL findings in the hyperacute phase were investigated and video-electroencephalogram findings obtained around ASL image acquisition in the hyperacute phase were evaluated., Results: Four ASL images were obtained for three patients before LS onset, with three images showing hyperperfusion areas and one image showing hypoperfusion areas. These hyperperfuion regions coincided with BTA on subsequent images of these patients.In one patient, the first ASL image was obtained in the late hyperacute phase and revealed hyperperfusion areas with a slightly abnormal change on diffusion-weighted image (DWI), which were not accompanied by ADC abnormalities. The second ASL image obtained 51 h after the first ASL, and before LS onset revealed more prominent hyperperfusion areas than the first ASL image, which were accompanied by BTA. In another patient, the ASL image obtained 82 h after ES revealed hyperperfusion areas without abnormal change on DWI or ADC., Conclusion: This study revealed that two patients exhibited hyperperfusion regions and another patient exhibited hypoperfusion regions among three patients who underwent ASL imaging during the period from 24 h after ES/ESs to LSs in patients with LSs or cooling initiation in patients without LSs due to early anaesthesia induction (late hyperacute phase). Further prospective studies on cerebral blood flow are required to explore the relationship among the timing of image acquisition, the presence of electrographic seizures, and ASL findings in patients with AESD., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Kawano, Tokutomi, Kikuchi, Sakata, Sakaguchi, Yokochi, Akita and Matsuishi.)

Objective: It is uncertain as to what extent the major bone matrix constituents, mineral and collagen, show inter-individual variation and dependence on age and sex in jawbones. The purpose of this study was to clarify this uncertainty using cadaveric mandibles and investigate the association of bone matrix with the number of existing teeth., Materials and Methods: Cortical bone samples (1 × 1 cm) collected from the mental of 48 cadaveric mandibles (27 men and 21 women; age range = 56-93 years and 63-103 years, respectively) were used to quantify three bone matrix indices: mineral content, collagen content and extent of lysine hydroxylation of collagen. Associations with age and comparisons by sex were evaluated based on bone matrix indices and the numbers of existing teeth. The numbers of existing teeth were compared between the groups showing low and high bone matrix index values., Results: A great amount of inter-individual variation was seen in all bone matrix indices. No bone matrix indices were associated with age, while the number of existing teeth was negatively associated with age. The bone matrix indices and number of existing teeth did not differ by sex. The number of existing teeth was nearly twice as high in the group showing high collagen content as in the low collagen group; however, an analysis of covariance showed a significant inter-group difference not from bone matrix indices, but rather from age. Interestingly, in comparison to femoral collagen, mandibular collagen showed lower lysine hydroxylation, which can represent an aspect of bone quality., Conclusions: Mandibular bone matrix shows great inter-individual variation and is independent of age and sex, but did not show as strong a relationship with tooth loss as age. Even so, mandibular collagen may represent a unique characteristic of bone matrix and deserves to be further investigated.

Bone undergoes constant remodeling throughout life. The cellular and biochemical mechanisms of bone remodeling vary in a region-specific manner. There are a number of notable differences between the mandible and long bones, including developmental origin, osteogenic potential of mesenchymal stem cells, and the rate of bone turnover. Collagen, the most abundant matrix protein in bone, is responsible for determining the relative strength of particular bones. Posttranslational modifications of collagen, such as intermolecular crosslinking and lysine hydroxylation, are the most essential determinants of bone strength, although the amount of collagen is also important. In comparison to long bones, the mandible has greater collagen content, a lower amount of mature crosslinks, and a lower extent of lysine hydroxylation. The great abundance of immature crosslinks in mandibular collagen suggests that there is a lower rate of cross-link maturation. This means that mandibular collagen is relatively immature and thus more readily undergoes degradation and turnover. The greater rate of remodeling in mandibular collagen likely renders more flexibility to the bone and leaves it more suited to constant exercise. As reviewed here, it is important in clinical dentistry to understand the distinctive features of the bones of the jaw.

A dodecapeptide (γ400-411) derived from a fibrinogen γ-chain carboxyl-terminal sequence recognizes specifically the active form of GPIIb/IIIa on the surface of activated platelets. For the purpose of efficient hemostasis, we previously developed ADP-encapsulated liposomes modified with human-dodecapeptide (HHLGGAKQAGDV, human-H12). On the other hand, the amino-acid sequence of H12 from rats is HHMGGSKQVGDM, having only 67% homology to that from humans. Here, we investigated the ability of rat-H12 in comparison with human-H12 to bind to platelets. Firstly, rat platelets were activated with phorbol-12-myristate-13-acetate (PMA), and the activation was confirmed by flow cytometry. Next, we evaluated the dissociation constant (K(d)) of human-H12 and rat-H12 for dissociation from rat platelets by using FACS. As a result, the K(d) of human-H12 and rat-H12 with respect to rat platelets was 2.78 ± 0.21 and 2.91 ± 0.22 μM, respectively. Furthermore, H12 from both species inhibited quite similarly the aggregation of rat platelets in platelet-rich plasma (PRP). These results suggest that H12 from different species with different amino acid sequences interacts similarly with GPIIb/IIIa on platelets., (Copyright © 2012. Published by Elsevier B.V.)

For the purpose of efficient hemostasis, we previously developed ADP-encapsulated liposomes modified with a dodecapeptide (HHLGGAKQAGDV, H12), H12-(ADP)Lipo. This liposome actually enhanced platelet aggregation in vitro, and showed significant hemostatic effect in vivo. Since fibrinogen (Fbg) is abundant in the bloodstream, it is unclear why this liposome binds platelets so efficiently, overcoming the competition with Fbg. Therefore, we investigated the relationship between H12 density on the liposome and the binding ability to platelets, and evaluated the inhibitory effect of Fbg on the binding of H12-(ADP)Lipo to platelets. As a result, the binding ability to platelets steeply increased depending on H12 density until it reached about 3×10(15) H12 molecules/m(2). The 50% inhibition concentration of Fbg on the binding of H12-(ADP)Lipo to platelets was about 25-fold over the concentration of H12 molecules on the liposome. Moreover, almost no inhibition by Fbg was observed at the physiological concentration of it. This result suggests that the ability of H12 to bind to GPIIb/IIIa increased overwhelmingly by the anchoring to the liposome that enabled the cooperative binding of H12 peptides to the platelets., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Lysyl oxidase (LOX) is an amine oxidase that is critical for the stability of connective tissues. The secreted proLOX is enzymatically quiescent and is activated through proteolytic cleavage between residues Gly(162) and Asp(163) (residue numbers according to the mouse LOX) by bone morphogenetic protein (BMP)-1 gene products. Here we report a novel processing of proLOX identified in vitro and in vivo. Two forms of mature LOX were identified and characterized by their immunoreactivity to specific antibodies, amine oxidase activity, and mass spectrometry. One form was identified as a well-characterized BMP-1 processed LOX protein. Another was found to be a truncated form of LOX resulting from the cleavage at the carboxy terminus of Arg(192). The truncated form of LOX still appeared to retain amine oxidase activity. The results from the proLOX gene deletion and mutation experiments indicated that the processing occurs independent of the cleavage of proLOX by BMP-1 gene products and likely requires the presence of LOX propeptide. These results indicate that proLOX could be processed by two different mechanisms producing two forms of active LOX.

At present, little is known about the age-related changes in jaw bones. The aim of this study was to characterize the mandibles of 6 month-old senile osteoporotic mice, SAMP6, and compare with those of age-matched controls, SAMR1. In comparison to SAMR1, SAMP6 showed thinner cortical bone, lower bone volume, and poorly organized collagen matrix. The collagen fibril diameter in SAMP6 was significantly smaller than that of SAMR1. In SAMP6 both collagen content and cross-links were lower than those of SAMR1, but the ratio of the major mature cross-link (pyridinoline) to its precursor reducible cross-link (dehydrodihydroxylysinonorleucine/its ketoamine) was higher in comparison to SAMR1. In addition, the extent of lysine hydroxylation of collagen was higher in SAMP6 than that of SAMR1. These results indicate that not only the quantity of collagen but also its quality are altered in SAMP6 and may result in the age-associated osteoporotic defects of mandibles.

In recent years, photodynamic therapy (PDT) with a photosensitizer and laser has been given attention, especially for the treatment of superficial cancers, such as lung, gastric, bladder and cervical cancer. In this study, in order to enhance the efficacy of PDT, photofrin liposome (PF-Lip) was prepared with dimyristoylphosphatidylcholine, dimyristoylphosphatidylglycerol and cholesterol. Polyethyleneglycol modified photofrin liposome (PF-PEG-Lip) was prepared by modification of PF-Lip with monomethoxypolyethyleneglycol-2.3-dimyristoylglycerol. PF-Lip and PF-PEG-Lip entrapped with photofrin with 81.0+/-5.9 and 81.2+/-9.2%, respectively. The particle size of each liposome was 114.3+/-5.7nm (PF-Lip) and 118+/-3.5nm (PF-PEG-Lip), respectively. It was suggested that PEGylated liposomes has no effect on the trapping ratio of PF and particle size. Phototoxicity was enhanced by liposomalization, especially PEG-modification. However, PF-PEG-Lip inhibited the uptake of photofrin into tumor cells. The amount of singlet oxygen from photofrin solution (PF-sol) and each liposome was PF-PEG-Lip=PF-Lip>PF-sol. The photofrin release revel of PF-PEG-Lip was lower than that of PF-Lip. In conclusion, the phototoxicity of PF-PEG-Lip was significantly higher than that of PF-sol or PF-Lip. It is expected that formation of a fixed aqueous layer on the liposome membrane by PEGylation physically changed it into the stable state of PF-PEG-Lip.

A 50-year-old woman who had been suffering from Behçet's disease came to our clinic. The patient developed recurrent oral aphthae, genital ulcers, and folliculitis when she was 25-year-old. In 1971 the diagnosis is of Behçet's disease was made and oral prednisolone was started. In 1976 oral and labial aphthae became worse, and after healing of these aphthae, adhesion of oral angle developed. At that time plastic surgery for adhesion was made. In 1990 the patient felt difficulty in opening the mouth again and operation for mouth was performed. In 1991 the patient was admitted to our hospital for the third time because of recurrent oral aphthae, vomitting, and dysphagia. Upper gastrointestinal series and endoscopic examination revealed that there was severe stenosis in the middle portion of esophagus. Above that lesion, dilatation of esophagus with retention of barium was observed. Forty mg/day of prednisolone with liquid meal was started, and operation for stenosis of the esophagus using bujie was performed twice. After that operation, the patient was able to take solid meals. Esophageal ulceration with Behçet's disease treated with prednisolone was reported and discussed with the review of the literture.

Ileocecal region is most commonly affected in intestinal Behçet's disease. Localized deep ulcerations which have a punched-out or undermining appearance with well-defined margin placing in this region had been noted in many cases. 41 patients with intestinal Behçet's disease were observed by colonofiberscope in Teikyo University Hospital from January 1982 to June 1988. In 10% (4 cases) of these patients, diffuse ulcerative lesions in the transverse colon and the distal colon were found. These diffuse lesions in the colon with Behçet's disease were seemed to be much like those associated with inflammatory bowel disease as ulcerative colitis and Crohn's disease in morphological characteristics. The clinical symptoms of these four cases with Behçet's disease including oral aphtha, genital ulcer, joint pain, skin eruptions, and eye involvement, preceded each colonic ulceration. The first two cases were affected with ulcerative lesion in the distal portion of the recto-sigmoid colon and the descending colon. And the last two were involved in the whole transversing colon by multiple deep ulcerations. Wide-spreading ulcerative lesion in the colon with Behçet's disease is a rare condition in the Japanese, and only two papers has been reported previously. Because clinical manifestations between Behçet's disease and inflammatory bowel disease are very similar in many points as oral aphthous ulcers, arthritis, eye involvement, skin eruptions, phlebitis, arterial occlusions, then, an overlapping field or a part of a spectrum of disease has been suggested by some authors. But, in the present circumstances, they are distinct disease entities, we think that these four cases are in an atypical condition with intestinal Behçet's disease.